# Engineering Software Systems for Quantum Computing as a Service: A Mapping
Study

Aakash Ahmad1, Muhammad Waseem2, Peng Liang3, Mahdi Fehmideh4 Arif Ali Khan5,
David Georg Reichelt1, Tommi Mikkonen2  1 School of Computing and
Communications, Lancaster University Leipzig, Leipzig, Germany  2 Faculty of
Information Technology, University of Jyväskylä, Jyväskylä, Finland  3 School
of Computer Science, Wuhan University, Wuhan, China  4 School of Business at
University of Southern Queensland, Queensland, Australia  5 M3S Empirical
Software Engineering Research Unit, University of Oulu, Oulu, Finland
<EMAIL_ADDRESS><EMAIL_ADDRESS><EMAIL_ADDRESS><EMAIL_ADDRESS><EMAIL_ADDRESS><EMAIL_ADDRESS><EMAIL_ADDRESS>
###### Abstract

Quantum systems have started to emerge as a disruptive technology and enabling
platforms – exploiting the principles of quantum mechanics – to achieve
quantum supremacy in computing. Academic research, industrial projects (e.g.,
Amazon Braket), and consortiums like ‘Quantum Flagship’ are striving to
develop practically capable and commercially viable quantum computing (QC)
systems and technologies. Quantum Computing as a Service (QCaaS) is viewed as
a solution attuned to the philosophy of service-orientation that can offer QC
resources and platforms, as utility computing, to individuals and
organisations who do not own quantum computers. To understand the quantum
service development life cycle and pinpoint emerging trends, we used evidence-
based software engineering approach to conduct a systematic mapping study
(SMS) of research that enables or enhances QCaaS. The SMS process retrieved a
total of 55 studies, and based on their qualitative assessment we selected 9
of them to investigate (i) the functional aspects, design models, patterns,
programming languages, deployment platforms, and (ii) trends of emerging
research on QCaaS. The results indicate three modelling notations and a
catalogue of five design patterns to architect QCaaS, whereas Python (native
code or frameworks) and Amazon Braket are the predominant solutions to
implement and deploy QCaaS solutions. From the quantum software engineering
(QSE) perspective, this SMS provides empirically grounded findings that could
help derive processes, patterns, and reference architectures to engineer
software services for QC.

###### Index Terms:

Quantum Software Engineering, Quantum Service Computing, Systematic Mapping
Study, Software Services.

##  I Introduction

Quantum computing (QC) has started to emerge as a disruptive technology and an
enabling platform – exploiting the principles of quantum mechanics – relying
on Quantum Bits (QuBits) that manipulate Quantum Gates (QuGates) to tackle
computationally intensive tasks efficiently [1]. QC systems are in a phase of
continuous evolution and despite being in a state of their infancy, such
systems have started to computationally outperform their classical
counterparts (i.e., digital computers) in applications such as quantum
information processing, bio-inspired computing, and simulation of quantum
mechanics [2]. Academic research [1] [3] and industrial initiatives led by
technology giants such as IBM, Google, and Microsoft [4] are striving hard to
achieve strategic advantages associated with quantum systems and software
technologies in a so-called ‘race to quantum economy’. A recent report
presented at the World Economic Forum titled State of Quantum Computing:
Building a Quantum Economy highlights that by the year 2022, public and
private investments in quantum computing technologies totalled $35.5 billion
[5]. Despite the strategic capabilities that can be attained via quantum
supremacy in computing; programming, operationalising, and maintaining a
quantum computer is a complex and radically distinct engineering paradigm [1].
To augment the quantum hardware development, state-funded projects, and global
consortiums are proactively funding initiatives such as the Quantum Flagship
[6] and National Quantum Initiative [7] to develop software ecosystems,
networking technologies, and human expertise for the alleged quantum leap in
computing [8].

Motivation: Pay-per-use QCaaS - Service-oriented systems have proven to be
useful in supporting utility computing model that relies on pay-per usability
approach for individuals and organisations to utilize a multitude of computing
services without the need to own or maintain them [9]. Since their early
adoption, pay-per-use service-driven systems have now grown from data storage,
video streaming, and entertainment, to resource-sharing applications that
represent a multi-billion dollar industry in service economies [10][11]. The
‘as-a-Service’ (aaS) model has provided the impetus to wide-scale adoption of
service systems that can offer a plethora of computing services including but
not limited to storage, computation, infrastructure, platform, and software to
end-users [10]. The aaS model can enable users and developers who can exploit
the QC platforms (e.g., processors, memory, simulators) offered by quantum
vendors, such as Amazon, Goole, and IBM [12]. Quantum Computing as a Service
(QCaaS) as in Figure 1 is a recent and quantum-specific genre of aaS model
that is built on the philosophy of service-orientation of QC, i.e., pay-per-
shot at QC resources instead of owning, programming, and/or maintaining
quantum computers [13]. Quantum vendors view pay-per-shot as an opportunistic
business model to generate revenue streams from their QC infrastructures,
where a shot is a single execution of a quantum algorithm on a quantum
processing unit (QPU). The QCaaS can alleviate the need to own or maintain
quantum computers and can help software and service developers to rely on
existing knowledge and best practices to develop software services that can be
executed on QC platforms [14]. Quantum software services enable developers to
wrap data and computations inside loosely coupled, fine-grained modules of
source code to execute tasks such as prime factorisation, key encryption, or
bio stimulations on QC platforms [13]. There is a growing interest in the
academic community and industrial vendors to research and develop solutions
for enabling quantum service-orientation [12][13].

Figure 1: A Generic View of the QCaaS Model

Needs for the mapping study: Systematic mapping studies (SMS) rely on
evidence-based software engineering approach to systematically and
reproducibly identify, analyse, synthesise, and document (i.e., map the trends
of) existing research on the topic under investigation [15]. The academic
community aims to exploit QC platforms for empiricism in quantum research
[12], while the vendors pursue a revenue stream as well as validation and
testing of their under-development quantum platforms, offered as a service
[13]. Synergising research and development on quantum computing with service-
orientation can allow researchers and developers to leverage existing design
principles, patterns, architectural styles, and modelling languages of
services computing to offer QC as a service [14]. Moreover, systemizing the
efforts to architect and implement QaaS requires discovering new patterns and
developing innovative frameworks rooted in empirically grounded guidelines to
research emerging challenges and develop futuristic solutions [16]. We
conducted this SMS based on two research questions to investigate (i) existing
solutions in terms of designing, implementing, deploying, and operationalizing
quantum software services and (ii)  emerging trends that can indicate
futuristic research on QCaaS. The results indicate that during quantum
service-orientation, software modeling languages (e.g., UML) and patterns
(e.g., service wrapping, API gateway) help in mapping functional requirements
to service implementation (e.g., Python code) that can be deployed on QC
platforms (e.g., Amazon Braket). Emerging trends indicate non-functional
aspects, model-driven engineering (low-code development), empirically
discovered tactics, human roles, and process-centric development of QCaaS.

Contributions and implications of this SMS are to:

  * •

identify and document a collective impact of existing research (published
academic evidence) to investigate the extent to which classical and quantum-
specific service-orientation can be applied to QCaaS.

  * •

highlight emerging trends - identifying existing gaps - that reflect the
dimensions of future research to develop emerging and next-generation of QCaaS
solutions.

Academic researchers can rely on mapping of existing research and vision for
future work to research and develop QCaaS solutions in a broader context of
QSE [1][6]. Practitioners who can rely on academic references about patterns
(reusability), modeling notations (representation), and implementation
(prototyping) to develop QCaaS [12].

##  II Research Context and Method

We now contextualise service-orientation for QCs in Section II-A and present
the research method in Section II-B.

###  II-A Context: Service-Orientation for Quantum Computing

####  II-A1 Quantum Computing Systems

We briefly overview a QC system that comprises of quantum hardware and
software elements as shown in Figure 2a). Fundamental to achieving quantum
computations are Quantum Bits (QuBits) that represent the basic unit of
quantum information processing by manipulating Quantum Gates (QuGates) [2]
[8]. Traditional Binary Digits (Bits) in classical systems (i.e., digital
computers) are represented as [1, 0] where 1 represents the computation state
as On and 0 represents the state as Off to manipulate binary gates in digital
circuits. In comparison, a QuBit represents a two-state quantum computer
expressed as $|0\rangle$ and $|1\rangle$. The state of a single Qubit can be
expressed as $|0\rangle=\begin{bmatrix}1\\\ 0\end{bmatrix}$ and
$|1\rangle=\begin{bmatrix}0\\\ 1\end{bmatrix}$ and quantum superposition
allows a QuBit to attain a liner combination of both states:

$|0\rangle=\left[\begin{array}[]{c}1\\\
0\end{array}\right]~{}~{}~{}~{}~{}+~{}~{}~{}~{}~{}|1\rangle=\left[\begin{array}[]{c}0\\\
1\end{array}\right]$ (1)

Based on Figure 2a), we distinguish between a Bit and QuBit such that a Bit
can take a value as either ‘Off:0’ or ‘On:1’ with 100% probability. In
comparison, a QuBit can be in a state of $|0\rangle$ or $|1\rangle$ or in a
superposition state with 50% $|0\rangle$ and 50% $|1\rangle$. In addition, two
QuBits can be entangled, and entangled QuBits are linked in a way that
observing (i.e., measuring) one of the QuBits, can reveal the state of the
other QuBit. Extended details about QuBits and QuGates to develop and operate
the QC systems are reported in studies like [1] and [12]. To utilise the
quantum computing resources, such as quantum processor and memory, there is a
need for control software that can program QuBits to manage QuGates of a QC
system. Quantum software systems rely on quantum source code compilers that
allow quantum algorithm designers and programmers to write, build, and execute
software for quantum computers. For example, a programmer can use a quantum
programming language, such as Q# (by Microsoft) or Qiskit (by Google) and use
a quantum compiler to enable programable quantum computations [4] [17].
Software systems that can manage and control quantum hardware find their
applications in areas including but not limited to quantum cryptography, bio-
inspired computing, and quantum information processing [1]. However, scarcity
of quantum hardware, lack of quantum software professionals, and economics of
owning or maintaining QC are some critical factors that impede commercially
viable quantum computers [2] [3]. Vendors who offer QCaaS platforms view
quantum service-orientation as an opportunistic business model that offers QC
resources to customers as utility computing [9] [12].

Figure 2: An Overview of the Quantum Service-Orientation

####  II-A2 Service-Oriented Computing

Services computing follows the SOA style that allows service users to discover
and utilise a multitude of available software services that encapsulate
computing resources and applications offered by service vendors/providers
[10]. Figure 2b) shows SOA style-based quantum servicing where a QC user
(i.e., service requester) can utilise the QC resources offered by quantum
vendors (i.e., service provider) by means of quantum services. In most cases,
QC systems of today are not capable of executing quantum algorithms wrapped
with large amounts of data, inputs, and outputs [2] [8]. As shown in Figure
2a), large volumes of data in quantum algorithms require more QuBits and
complex QuGates that result in deep quantum circuiting and consequently
increased errors referred to as noisy intermediate-scale quantum (NISQ) [4].
To address the issues like NISQ, the classic-quantum split pattern slices the
overall quantum software or application into classical modules (pre/post-
processing) and quantum modules (quantum computation) that result in hybrid
applications[16]. One of the prime examples of classic-quantum split patterns
is Shor’s algorithm which involves quantum computations for finding the prime
factors of an integer with its application in computer security and
cryptography. Quantum service-orientation when viewed from a utility computing
perspective can minimise the quantum divide, a prevailing issue highlighted at
the World Economic Forum 2023, between states/entities that own or lack QC
systems, technologies, and infrastructures [18].

###  II-B Research Method for the SMS

We now discuss the research method, driven by three phases as illustrated in
Figure 3, based on the guidelines to conduct the SMS [15].

####  II-B1 Phase I – Specifying the Research Questions

Research questions (RQs) are fundamental to conducting the SMS and documenting
the results. We outlined two RQs for this SMS.

RQ-1: What solutions are reported in the literature to support the development
of quantum computing as a service?

Objective(s) \- To investigate state-of-the-art in terms of existing solutions
that enable or enhance QCaaS computing. A multi-perspective analysis can
reveal the functionality offered by the solutions, modeling languages and
patterns to design the solutions, and programming technologies along with
deployment platforms to implement and operationalise the solutions.

RQ-2: What are the emerging trends of research on quantum computing as a
service?

Objective(s) \- To identify and discuss the emerging trends that can help
pinpoint the prevalent challenges and their solutions as dimensions of
potentially futuristic research on QCaaS. The emerging trends can help to
provide a road map for progressing research and development on QCaaS.

TABLE I: Criteria for Screening and Qualitative Assessment of Selected Studies
Study Selection Step I - Screening of Identified Studies
---
S1 - The study does not discuss any solution or proposal for quantum computing
as a service
S2 - The study is not reported in English
S3 - The study is a duplicate study. Duplicate studies are studies with
overlapping contents, e.g., a conference paper extended as a journal article.
S4 - The study is a secondary study/survey paper
| Exclude the study if the answer to any of the criteria in Step I (S1 - S4)
results in Yes, otherwise,
---
Include the study for quality assessment in Step II
Study Selection Step II - Quality Assessment of the Identified Studies
Q1 - Study objectives and Contributions are clear? [Yes = 1, Partially = 0.5,
No = 0]
Q2 - Research method to conduct the study is reported [Yes = 1, Partially =
0.5, No = 0]
Q3 - Design and/or implementation details of solution are provided [Yes = 1,
Partially = 0.5, No = 0]
Q4 - Details for Experiments/Evaluation/Demonstration of Solution are provided
[Yes = 1, Partially = 0.5, No = 0]
Q5 - Study limitations and needs for future research are discussed [Yes = 1,
Partially = 0.5, No = 0]
| Exclude the study that has a quality assessment score (Q1 – Q5) less than
2.0, otherwise
---
Include the study for review and data extraction in Table 2

####  II-B2 Phase II – Identifying and Selecting the Literature for SMS

Based on the guidelines for literature search, we formulated a generic string
to be executed on prominent Electronic Data Sources (EDS) [19] including IEEE
Xplore, ACM Digital Library, Springer Link, Science Direct, Springer Link, and
Wiley Online Library. Google Scholar was used as a complementary EDS to ensure
that we did not miss any relevant study for selection. The search string
presented in Figure 3 is generic that combines logical operations AND, OR) to
compose the key terms (e.g., Quantum AND Service OR Cloud), customized for
each EDS individually. Customised search strings are provided as part of the
SMS protocol [20]. We conducted a pilot search to assess the need for any
customisation to the search string(s) or any filters applied on specific EDS
to avoid an exhaustive search resulting in a significant number of unrelated
studies. For example, we limited our search on IEEE Xplore from ‘Full Text &
Metadata’ to ‘Document Title’ as searching for our defined key terms in full
text and metadata yielded a significant amount of irrelevant studies (e.g.,
cloud services, quantum hardware).

Screening and Quality Assessment: By executing the customised search strings
on five selected EDS, the SMS process retrieved a total of 55 potentially
relevant studies. To complement the automated search on EDS, we applied the
forward snowballing process [17], as a manual effort. The forward snowballing
approach involves looking up the references or bibliography sections of 55
studies, referred to as the seed set in snowballing, to see if any relevant
cited literature can be found. The forward snowballing helped us to identify a
total of 13 studies resulting in a total of 68 studies (55: EDS and 13: snow-
balling). To assess and select the studies for review, we performed study
screening based on criteria (Step 1: S1 – S4) in Table I. Most of the studies
identified during the snowballing failed the screening criteria S3 and S4
which means either the studies were duplicate studies or secondary/survey
studies that cannot be included in the review. Based on the screening of
identified studies, more specifically reading through the titles, abstracts,
and conclusions we shortlisted a total of 11 potentially relevant studies to
be qualitatively assessed (Step II: Q1 – Q5) for their inclusion in the review
for SMS. Based on the quality assessment, we excluded 2 studies to finally
select a total of 9 studies to be included in the review. The list of selected
studies for the SMS is provided in Appendix A.

Figure 3: Overview of the Research Method

####  II-B3 Phase III – Documenting the Results

To document the results, i.e., answering RQs objectively, we extracted the
data from the selected studies in Appendix A and documented it using a
structured format, having seven criteria, in Table II. The criteria focus on
conceptualising, designing, developing, and deploying quantum software
services by following the IBM SOA foundation life cycle (SOA life cycle for
short) [21]. To contextualise QCaaS from Figure 2 and to ensure fine-grained
analysis of SMS data, we have divided the ‘Model’ activity from SOA life cycle
into two activities namely Conception and Model to distinguish between
functional needs (conception) and representation (modeling) of quantum service
design. Model represents the conception as the design specification of
functional needs for quantum services. We do not have the ‘Manage’ phase from
SOA life cycle as we could not find any evidence in the literature that
supports identity, compliance, and business metrics management of quantum
services.

  * •

Conception as the initial activity in the service life cycle aims to
conceptualise the functional aspects of quantum services by capturing the
details of required functionality, i.e., functional requirements. Conception
aims to identify: what are the business needs of a quantum service?

  * •

Model activity aims to translate the conception into a design that acts as a
blueprint for implementing quantum services. Model focuses on: how to
represent the conception as the design of the solution?

  * •

Assemble focuses on implementing the design to produce concrete, i.e.,
executable specification of quantum services. Assemble aims to address: how to
implement the design as executable services?

  * •

Deploy as the last activity aims to deploy the assembled solution for
operationalisation and usage of quantum services. Deploy focuses on: what
platforms can be used to deploy the assembled (implemented) solution?

####  II-B4 Threats to the Validity of SMS

Systematic literature reviews and mapping studies are prone to a number of
validity threats that refer to deviation, limitations, or invalidation of
study results when applied to a theoretical or practical context. Construct
validity of the SMS corresponds to the rigor of study protocol and
methodological details to extract, analyze, and synthesise the data to
objectively answer the RQs and present the data systematically. To avoid this
threat, i.e., avoiding the bias in data extraction and documentation, we
applied well-practiced guidelines [15, 19], derived the search strings (Figure
3), and devised a structured format (Table II) to collect and present the data
consistently. Internal validity examines SMS design, conduct, and analysis to
answer the RQs without bias. To minimize this threat, we synthesized the data
based on the well-known IBM SOA life cycle [21] that structures the results
into fine-grained life cycle activities. We documented the results while
performing a quality assessment (Table I) and a well-defined service life
cycle template. External validity of the SMS refers to the extent to which the
findings of study can be generalised/externalised to research and development
projects. It is challenging to foresee and outline the predictive implications
of the study results. We have outlined the implications and generalization of
study findings (Table II, Figure 4, Figure 5) can provide the basis for
creating a reference architecture for QCaaS as future work. The documented
results are discussed in Section III (RQ-1) and Section IV (RQ-2).

##  III Engineering Software for QCaaS (RQ-1)

We now discuss the existing solutions, reported in the literature, that
support the development of quantum services to operationalise QCaaS solutions.
The data extracted from the selected studies is presented in Table II and
visualised in Figure 4. Table II can be viewed as a catalogue that organises a
summary of the core findings to answer RQ-1 based on the four activities of
the SOA life cycle (Phase III, Figure 3).

Illustrative Example: Figure 4a) exemplifies the service life cycle with
functional aspects that requires a quantum service to compute the prime
factors of an integer. Functional aspects need modeling and that uses Unified
Modeling Language (UML) component diagram [22] as the modeling notation to
specify computational elements (components) and their interconnections
(connectors) in a service. The Classic-Quantum split pattern [16] is applied
to slice the functionality between a classical computer (pre-/post-processing,
e.g., Gen_Num component) and a quantum computer (prime factorization,
Factorize component). The model acts as a blue-print to support assembly of a
services using a programming language (Qiskit code snippet) that converts the
design specifications of a service to its executable specifications. Finally,
deployment activity is shown as UML deployment diagram to configure the
assembled service on a quantum computer provided by the quantum vendor (Amazon
Braket).

###  III-A Conception: Functional Aspects

During the conception activity, functional aspects of a service relate to
identifying and outlining the functionality to be offered by a quantum
service. The functionality can be achieved via service execution on a quantum
computer (provider), whereas the service is developed or invoked by the user
(requester). Figure 2 shows that, in order to exploit QC platforms for quantum
functionality, service requesters can develop/discover new and/or available
services, such as quantum simulation or quantum cryptography using the SOA
patterns [10]. In the SMS, we identified a multitude of functional aspects for
quantum services and organized them into five categories namely experimental,
service delivery, number crunching, data searching, and natural computing as
shown in Table II. For example, Figure 4a) highlights the generic functional
aspect of number crunching that involves prime factorisation of integers for
Shor’s algorithm [1][2].

The diversity of existing functional aspects is proportional to the capability
of the current era of quantum computers that is considred as limited due to a
number of factors such as simplistic quantum circuitry (e.g., less
QuBits/QuGates) and quantum errors (e.g., NISQ) [4]. Quantum software services
that support functional aspects of QC are merely capable of checking the
status of quantum circuits (experimental) or generation of random numbers
using quantum hardware (number crunching). Functional aspects reflect only a
partial view of system design in terms of offered functionality that should
not overlook the non-functional or quality aspects of the QCaaS solutions. For
example, resource efficiency in terms of utilizing minimal available QuBits to
generate prime factors can ensure the required functionality and desired
quality (e.g., service efficiency, execution performance) of QCaaS.

Functional aspects of quantum services, in general, are rather limited to
basic quantum experimentation and numerical processing. The limitation
reflects the existing capabilities of QCs and consequently the offered
services by quantum vendors. Investigating the non-functional aspects can help
outline the quantum significant requirements (QSRs) in terms of required
functionality and desired quality of the service that currently lacks in the
existing literature.

Figure 4: An Overview of the Mapping Study Results

###  III-B Modeling: Notations and Patterns

During service modeling, modeling notations, such as Q-UML or ontological
models can help create a blueprint for the implementation of functional
aspects [22]. Patterns can complement the notations by providing reusable
knowledge and design rationale to architect the quantum services [13] [16].

TABLE II: Data Extracted for SMS from Reviewed Studies (SOA lifecycle
activities [20])
---
| Conception | Modeling | Assembly | Deployment
Study ID & Research Type |  | Functional
---
Aspects
| Modelling
---
Notation
| Software
---
Pattern
| Service
---
Use case
| Service
---
Programming
| Quantum
---
Platform/
Vendor
|
---
[S1]
|
---
Quantum Service
Delivery
|
---
Deployment
Diagram
|
---
API Gateway
|
---
Optimal Service
Provider
|
---
Python, Flask
|
---
|
---
[S2]
|
---
Enterprise Services
Development
|
---
Business Process
|
---
Layered
Architecture
|
---
Process Automation
|
---
No Evidence
|
---
No Evidence
|
---
[S3]
|
---
Quantum Random
Number Generation
Quantum Search Algo
|
---
Class, Sequence
Diagram
|
---
Classic- Quantum Split
|
---
Mathematics
|
---
Q sharp
|
---
IBM Quantum
|
---
[S4]
|
---
Integer Factorisation
|
---
Deployment Diagram
|
---
Solution
|
---
Mathematics
|
---
Python
|
---
|
---
[S5]
|
---
Experimental Quantum
Service Computing)
|
---
No Evidence
|
---
Service Wrapping
|
---
Optimisation
|
---
Python, Flask
|
---
|
---
[S6]
|
---
Experimental Services
Algorithm
|
---
Sequence Diagrams
|
---
API Gateway
|
---
Algorithm as
a Service
|
---
Python
|
---
Rigetti
|
---
[S7]
|
---
Integer Factorisation
|
---
Directed Graph
|
---
API Gateway
|
---
Optimisation
|
---
No Evidence
|
---
|
---
[S8]
|
---
Bio-inspired
Computing
|
---
Ontologies
|
---
Repository
Pattern
|
---
Simulation
|
---
No Evidence
|
---
No Evidence
|
---
[S9]
|
---
Integer
Factorisation
|
---
No Evidence
|
---
Service Wrapping
|
---
No Evidence
|
---
Python
|
---

Modeling notations are fundamental to the creation, maintenance, and evolution
of models such as ontological structures and graph-based diagrams that provide
a visual representation, whereas architectural description languages support a
textual specification for software-intensive systems [22]. Recent trends in
software engineering that promote model-driven and low-code application
development have resulted in transitioning developers’ focus from coding to
software modeling for implementation [7]. Low code application development
process leverages the principle and practices of model-driven engineering to
utilise model(s) as first-class entities in software development [17][23].
Investigating software models and modeling notations that help create service
models is essential to support model-driven perspective to QSE, consequently
facilitating quantum code developers to abstract implementation-specific
complexities, via model-driven QSE, while developing quantum services [23].
This SMS indicates three main types of notations to model services in QCaaS
that include the Unified Modeling Language (UML), graph-based models, and
process models highlighted in Figure 4b). UML-based models are represented via
a multitude of notations, such as class and component diagrams that represent
the structure, while sequence and deployment diagrams represent runtime or
behavioural view of QCaaS. Graph-based models contain directed graphs and
ontologies, whereas process models rely on automating the business processes
of an enterprise as quantum services. For example, the study [S3] reports a
class diagram as a structural view of the system to represent the attributes
and methods of entities (user, service provider, authentication etc.) of
quantum computing as a service. UML diagrams and profiles represent the
status-quo in software modeling and are seen as the de-facto notation in the
software and service ’ community to model classical software with growing
adoption in QSE [22].

Design patterns represent a concentrated wisdom of software designers that can
be leveraged to address design and implementation issues, addressing
functionality and quality, effectively and efficiently. Considering a lack of
professional expertise in QSE (e.g., quantum domain engineers, quantum
algorithm designers, quantum software architects etc.) patterns as artifacts
of reuse can help novice developers during quantum software development to
rely on existing best practices [1][13]. This SMS highlights that the
literature on QCaaS reports five patterns, namely the API Gateway, Layered
Architecture, Classic-Quantum Split, Service Wrapping, and Repository Pattern.
Figure 4c) depicts pattern thumbnails as an abstract view of the identified
patterns. Patterns are generally documented as templates or pattern languages,
here we only focus on overviewing the reported patterns for QCaaS, while
details for pattern representation and documentation can be found in [23]. The
Classic-Quantum Split pattern [16] is a quantum version of the Splitter
pattern, driven by quantum workflow, that splits computation tasks into tasks
that can be generated and executed on classical machines (e.g., random number
generation) and tasks that can be executed on quantum machines (e.g., prime
factorisation). The pattern aims to address issues like NISQ by splitting
quantum software into classical and quantum parts as a hybrid application
[2][4].

Modeling notations can assist software engineers to transit their focus from
implementation towards design perspective. Modeling can incrementally
transform functional aspects to service models leading to service
implementation via model-driven engineering or low-code development. Patterns
(classical or quantum-specific) can facilitate developers to architect and
implement quantum-age software services by relying on reusable knowledge and
best practices of service-orientation.

Recently, a number of studies have focused on organising quantum software
patterns as a body of knowledge in QSE, however, there is no evidence of
empirically-derived methods to discover and document patterns for quantum
services computing. SOA-specific patterns like API Gateway and Service
Wrapping patterns can be tailored to address QCaaS solutions. There is a need
for mining repositories and knowledge resources to discover reusable knowledge
and best practices from quantum software development projects that can to be
documented as tactics and patterns for QCaaS solutions.

###  III-C Assembly: Application Domain and Programming

Assembling the quantum services involves identifying the application domains
and exploiting the programming languages as implementation technologies to
develop executable specifications from the service model [10] [12].

Application Domain is also referred to as the implementation use cases or
practical context to which the QCaaS solutions can be applied. For example,
quantum security represents an application domain for quantum software
servicing where a service can be invoked to implement cryptography protocols
to generate and manage a secure quantum key [8]. The results of this SMS
indicate four application domains, namely OptimiSation, Process Automation,
Mathematics, and Quantum Simulation. The application domains may impact the
selection of programming languages and tools for service implementation. For
example, the study [S3] uses Q# as the programming language that can be
developed and compiled in Microsoft .Net framework for executing quantum
algorithms.

Service Implementation involves programming languages that represent a system
of notation or source coding scripts for implementing quantum services to
manage and operationalise QC resources [17] [22]. In recent years, a number of
Quantum Programming Languages (QPLs) including but not limited to Q# by
Microsoft or Cirq by Google have emerged to provide specialized programming
syntax, framework, and environments to develop, execute, and deploy quantum
source code. Insights into programming languages can reveal if classical
programming languages (e.g., C, Java, Python etc.) suffice for QCaaS
implementation or if there is need for more specialised QPLs (Q#, Cirq etc.).
The SMS results indicate three programming languages, namely Python, Java, and
Q#, as the preferred languages to implement quantum services. Based on the
details of source coding, Figure 4f) distinguishes between native code of a
language and specialised libraries/application programming interfaces (APIs)
being developed using a specific language. For example, the studies [S4, S5]
used native Python code to implement quantum micro-servicing for
experimentation. In comparison, the study [S1] used Flask as a Web framework
written in Python to develop a solution for optimal delivery of quantum
services on Amazon Braket. Python is the most preferred programming language
both in terms of native code as well as specialised libraries of Python that
include Flask and Qiskit as open-source language frameworks and Cirq which is
adopted by Google.

Application domains represent the practical context/use cases of quantum
services and may impact the selection of programming languages and tools for
implementation. Programming languages provide a system of notation for source-
coding of quantum services. Classical programming languages, such as Python
represent a predominant choice over QPLs to implement QCaaS due to more
comprehensive documentation and familiarity of Python in service developers’
community.

###  III-D Deployment: Quantum Platform

The deployment activity supports the selection of QC platforms on which
services can be deployed for their operationalisation and execution. Platform
providers also referred to as quantum vendors offer computing infrastructure
in terms of hardware as well as software that allows service developers to
develop and/or utilise the quantum services. Deployment represents the last
activity in the SOA life cycle that is represented as a UML deployment diagram
in Figure 4a). This SMS identified a total of three quantum vendors for the
deployment of quantum services, namely Amazon Bracket, IBM Quantum, and
Rigetti. Amazon Braket (a managed Amazon Web Services (AWS)) is the most
preferred platform to design, test, and run quantum algorithms. One of the
reasons for selecting Amazon Braket for service deployment is that it can
allow service users/developers to design their own quantum algorithms. This
can be particularly handy for novice developers unfamiliar with the
technicalities of quantum systems to utilise a set of pre-built algorithms,
tools, and documents to develop and manage quantum services on Amazon
platform.

Quantum platforms leverage cloud computing infrastructures to support quantum
service-orientation. Amazon Braket is the predominant quantum vendor that can
enable novice developers to exploit some pre-built algorithms, programming
tools, and service documentation that lack on other quantum platforms.

##  IV Emerging Trends of Research on QaaS (RQ-2)

We now answer RQ-2 that aims to report the emerging trends that indicate
dimensions of potential future research on QCaaS. To identify these trends, we
specifically reviewed the details about objectives/contributions,
evaluation/demonstrations, and limitations/future research in each study
during quality assessment (Q-1, Q-4, Q-5 in Table I). We have visualised the
identified emerging trends in Figure 5 as per the SOA life cycle activities.
For example, Figure 5 highlights that during the conception of quantum
services, Quantum Significant Requirements (QSRs) should include quality
aspects that complement the functional aspects to ensure the required
functionality and desired quality of QCaaS as part of quantum domain
engineering activity in QSE.

###  IV-A Process and Human Roles in QCaaS Development

Process-centred engineering is manifested in service life cycle to structure a
multitude of activities, such as service design, development, and delivery,
into a coherent process that can be executed in an incremental fashion [23].
Although the evidence from the selected studies is accumulated and organized
under SOA life cycle in Table II, however, at the individual scale, the
studies lacked a process-centric approach and highlighted the needs for
processes attuned to the needs of QSE [23]. These processes, such as Quantum
DevOps, Quantum microservicing or agile methods for quantum service/software
etc., are seen as quantum-genre of SE processes that are better aligned with
the needs of QSE [24]. For example, in the agile method for QSE, quantum
domain engineering can help accumulate the domain information of a quantum
system (hardware/software) to develop a design model that can act as a
blueprint to implement quantum software and services. Process-centric
approaches can also support tools (for automation) and professional roles
(human decision support) to engineer quantum services. We identified the need
for human roles as QSE professionals to effectively undertake QCaaS
development.

Process-centred approaches, such as Quantum DevOps, Quantum microservicing or
agile methods, can enable an incremental development and delivery of quantum
software services. Human roles can enrich the process - synergising knowledge
of quantum physics practices of software engineering - to support activities
of quantum domain engineering, software architecting, and simulation
management as expertise that currently lacks in quantum service-orientation.

###  IV-B Quantum Significant Requirements

The concept of Quantum Significant Requirements (QSRs) can be traced to well-
established role of Architecturally Significant Requirements (ASRs) in
software and service engineering. QSRs as part of the quantum domain
engineering activity can help elicit and document the functional and non-
functional aspects (also quality aspects or attributes) of quantum software.
Existing research primarily focuses on functional aspects of services while
overlooking the non-functional aspects that include but are not limited to
QuBit utilisation, energy efficiency, quantum vendor lock-ins, QPU elasticity,
quantum error mitigation, that impact the development and operationalisation
or QCaaS solutions. For example, during the quantum domain engineering
activity the hardware aspects (operations of QuGates) can be mapped to
software aspects (components and connectors) that can help with splitting the
computation tasks between classical and quantum computers using the classic-
quantum split pattern.

The notion of QSRs is rooted in the concept of ASRs that aims to identify,
classify, and document functional and quality aspects of quantum software
services. QSRs for quantum services can complement the functional aspects with
quality requirements to ensure the required functionality and desired quality
of service.

###  IV-C Model-driven Quantum Software Servicing

Model-driven Service Engineering (MDSE) enables software engineers and
architects to rely on models that can abstract complex and implementation-
specific details with human comprehensible visual notations to design and
implement software services. Specifically, by exploiting MDSE, software
engineers can apply the model transformation to transform the design models
into implementation (source code) and validation (test case) models. Modeling
notations, such as Service-oriented architecture Modeling Language (SoaML) and
more specifically the Q-UML specification, provide a metamodel and a UML
profile for the specification and design of services within a service-oriented
architecture. MDSE can benefit novice developers to to map the flow of
algorithms and modules of source code to graphical models for low-code (model-
driven) development of quantum services.

Model-driven Quantum Service Development can leverage the principle of MDSE
and modeling notations like SoaML and Q-UML to abstract implementation-level
complexities with design-level models driven by QSRs. To exploit model-driven
development, there is a need for tool support that could enable automation
(e.g., model transformation tools) and human decision support (e.g., quantum
software architects) to quantum software servicing using MDSE.

Figure 5: Overview of Emerging Research Trends TABLE III: A Review of the
Relevant Secondary Studies Quantum Software Engineering
---
| Study
---
Reference
| Type of
---
Study
| Focus of
---
Study
| Core
---
Findings
| QSE
---
Activity
| Publication
---
Year
[25] |  | Literature
---
Review
| Quantum
---
Software
Engineering
| QSE life cycle, quantum software
---
engineering processes, methods, and tools.
| Software
---
Life cycle
2020
[26] |  | Systematic
---
Review
| Quantum
---
Software
Architecture
| Quantum software architecting activities,
---
modelling notations, patterns, and tools
for architectural development
| Software Design
---
and
Architecture
2021
[17] |  | Repository Mining
---
and
Practitioner Survey
| Quantum
---
Programming
Languages
| Mining repositories and interviewing
---
practitioner to investigate quantum
programming languages
| Software
---
Implementation
2022
[27] |  | Repository
---
Mining
| Quantum
---
Issues
| Mining repositories to identify technical
---
debts in open-source quantum software
| Software
---
Implementation
and Testing
2022
[28] |  | Vision
---
Paper
| Quantum
---
Software
Architecture
| QSE life cycle and comparing quantum
---
computers with their classical
counterparts and vision for future research
| Software
---
Life cycle
2022
Quantum Services Computing
[14] |  | Literature
---
Survey
| Quantum
---
Cloud
Computing
| Programming quantum computers and
---
investigating hybrid software consisting
of classical parts and quantum parts.
| Service Design
---
and
Architecture
2020
[29] |  | Literature
---
Survey
| Quantum
---
Service
Computing
| Potential and limitation of integrating
---
quantum computing with cloud computing
| Service
---
Lifecycle
2015

###  IV-D Empiricism in Mining Quantum Service Patterns

Pattern-based software service engineering relies on architectural design and
implementation strategies and best practices that can be reused to deliver
software services [21]. Existing solutions employ a number of pattern-based
solutions, such as classic-quantum split and service wrapping pattern,
however, there is no evidence on an empirical discovery of patterns and
tactics as reusable knowledge [30]. A lack of empiricism in discovering new
patterns hinders the reusability of service design and implementation
knowledge during quantum service engineering. One possible dimension for
pattern discovery is mining software repositories or social coding platforms
(e.g., GitHub) that contain raw knowledge that can be mined as patterns.
Pattern-based solutions could complement human expertise with available best
practices for service design and implementation.

Pattern discovery via empirically-grounded methods, i.e., mining repositories
or social coding platforms of quantum software development, can help leverage
reusable design rationale for quantum service engineering. Pattern languages
can empower the role of quantum software architects and algorithm designers to
rely on reusable knowledge and best practices as opposed to ad-hoc and once-
off solutions.

###  IV-E Continuous Testing and Delivery of Quantum Services

With an adoption of agile software engineering in quantum software development
context [24], there is a need for light and adaptive methods to ensure a
continuous development and delivery of quantum software services. The
literature suggested a lack of solutions on testing the software services. The
continuous testing and continuous delivery can help CT/CD to test the services
against QSRs more effectively and deliver them rapidly. Quantum service
testing can involve simulation or regression tests against the QSRs.

Continuous Testing and Continuous Delivery (CT/CD) relies on agile software
engineering methods to help deliver quantum software services rapidly and
reliably. CT/CD can provide strategic benefits to vendors by adding new
services to their quantum platforms.

##  V Related Survey-based and Empirical Studies

We now review the relevant research rooted in survey-based evidence or
empirical studies on (i) engineering and architecting quantum software
(Section V-A), and (ii) quantum services computing (Section V-B), as in Table
III.

Interpretation of the Review: To compare and summarise objectively, Table III
highlights each study using five-point self-explanatory criteria including (a)
type of study (adopted from [15]), (b) focus of study, (c) core findings, (d)
QSE activity supported by the study, and (e) year of publication, each
exemplified below. For example, the study [26] presents a systematic review,
available since 2021, as part of evidence-based software engineering to focus
on architecting quantum software. It presents the core findings about
architectural life cycle and state-of-the-art on architectural modeling,
patterns, and tools to architects develop quantum software.

###  V-A Architecting and Engineering Quantum Software

Quantum Software Engineering (QSE) has emerged as the most recent genre of
software engineering (SE) that allows practitioners to adopt a process-centric
and systematic approach develop software-intensive systems and applications
for QC [25, 28]. Some recently published survey-based studies on QSE highlight
that existing SE principles and practices can be tailored to develop quantum
software, however, issues specific to QC, such as operationalising
QuBits/QuGates, quantum domain engineering, and quantum-classic software
split, require new engineering methods to tackle these challenges [28]. To
derive new methods and processes, the QSE research community is striving to
organize a body of knowledge and academic collaborations that can be
stimulated via dedicated publication forums. Academic discussions at the
publication fora and published results [1][4] have highlighted that in
addition to the engineering principle and practices, human knowledge and
expertise require fundamental knowledge of quantum mechanics to effectively
design algorithmic solutions for QSE projects [17]. The current generation of
software architects and developers who lack the foundational knowledge of
quantum mechanics may be hindered or find themselves under-prepared for
quantum software development [26]. Software architecture is being viewed as a
solution that can abstract complexities of implementation by representing
software to be developed as architectural components and connectors. A
recently conducted systematic review of architectural solutions puts forward
five architecting activities to guide software designers to engineer quantum
software solutions in an incremental manner [26].

###  V-B Quantum Services Computing

Quantum service-orientation is a recent trend initially pushed by QC vendors
to allow developers who can compose and invoke software services on remotely
hosted quantum systems and infrastructures [14]. Quantum service computing
initiatives, such as Amazon Braket and Q experience, have paved the way for
academic research to propose solutions for quantum cloud, quantum services
computing, and quantum as a service. Recent research reviews inform about the
current progress and emerging challenges for quantum services computing that
include but are not limited to hardware availability, quantum noise, and
quantum-classic split [29]. Software researchers are striving to synergise
existing methods of microservicing and quantum software development such as
Quantum DevOps to develop quantum microservices [24].

##  VI Conclusions and Future Work

Quantum service orientation allows QC vendors to offer end-users’ access to
computational resources - enabling shots at QPUs - by following the utility
computing model. Recently, research and development on QSE have started to
synergize the principles of service-orientation and practices of QC
(algorithms, simulations, QuGates etc.) to enable the adoption of QCaaS by
individuals and enterprises to attain quantum supremacy in modern day
computing. To this end, we used the systematic mapping study approach to
investigate (i) existing solutions for quantum service development that enable
or enhance QCaaS, and (ii) emerging trends that highlight the needs for
ongoing and future research on QCaaS. The results of this SMS as structured
information (Table II) and visual illustrations (Figure 2-4) highlight the
strengths, limitations, and potential for future research from the QSE
perspective.

Implications and Future Work: The primary implication of this SMS is to
establish an evidence-based body of knowledge for service development that
leverages design notations, patterns, and architectural approaches
highlighting the needs for human-centric and process-driven QCaaS development.
The results of this SMS establish the foundations for future work in three
directions that include (a) conducting practitioners’ survey, (b) implementing
the reference architecture, and (c) mining social coding platforms for
empiricism in QCaaS computing. The literary foundations can help us to design
an empirical study that aims to engage service developers and engineers in a
workshop (activity and survey) to seek their feedback and synthesise the
results as practitioners’ perspectives to complement the evidence from
academic research. We also plan to mine social coding platforms (e.g., GitHub)
to empirically discover knowledge and understand the practices adopted by
developers’ communities in open-source QCaaS.

TABLE IV: List of the selected studies of this SMS | Study
---
ID
| Authors, Title
---
and Venue
| Publication
---
Year
| Quality
---
Score
[S1] |  | G. Jose, J. Rojo, D. Valencia, E. Moguel, J. Berrocal,
---
and Juan. Murillo. Quantum Software as a Service
through a Quantum API Gateway. IEEE Internet Computing
2021 | 4.0
[S2] |  | Kumara, Indika, Willem-Jan Van Den Heuvel, and
---
Damian A. Tamburri. QSOC: Quantum service
oriented computing. SummerSOC
2021 | 3.0
[S3] |  | Nguyen, Hoa T., Muhammad Usman, and Rajkumar
---
Buyya. QFaaS: A Serverless Function-as-a-Service
Framework for Quantum Computing. arXiv
2022 | 5.0
[S4] |  | Moguel, Enrique, Javier Rojo, David Valencia, Javier
---
Berrocal, Jose Garcia-Alonso, and Juan M. Murillo.
Quantum service-oriented computing: current landscape
and challenges. Software Quality Journal
2022 | 4.0
[S5] |  | Rojo, Javier, David Valencia, Javier Berrocal, Enrique
---
Moguel, Jose Garcia-Alonso, and Juan Manuel Murillo
Rodriguez. Trials and tribulations of developing hybrid
quantum-classical microservices systems. Q-SET
2021 | 3.5
[S6] |  | De Stefano, Manuel, Dario Di Nucci, Fabio Palomba,
---
Davide Taibi, and Andrea De Lucia. Towards Quantum
algorithms-as-a-service. QP4SE
2022 | 2.5
[S7] |  | Valencia, David, Enrique Moguel, Javier Rojo, Javier
---
Berrocal, Jose Garcia-Alonso, and Juan M. Murillo.
Quantum Service-Oriented Architectures: From Hybrid
Classical Approaches to Future Stand-Alone Solutions.
Quantum Software Engineering
2022 | 3.5
[S8] |  | Barzen, Johanna, Frank Leymann, Michael Falkenthal,
---
Daniel Vietz, Benjamin Weder, and Karoline Wild.
Relevance of near-term quantum computing in the
cloud: A humanities perspective. CLOSER
2021 | 4.0
[S9] |  | Valencia, David, Jose Garcia-Alonso, Javier Rojo,
---
Enrique Moguel, Javier Berrocal, and Juan
Manuel Murillo. Hybrid classical-quantum
software services systems: Exploration of the
rough edges. Quality of Information and
Communications Technology
2021 | 3.5

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purifying(1) | evangelistic(1) | clearing(1) | soulful(1) | communal(1) | testament(1)
social(1) | solitudinous(1) | shared(1) | comforting(1) | interconnected(1) | profound(1)
guideline(1) | fostering(1) | connecting(1) | celebrate(1) | journeying(1) | homage(1)
blending(1) | integrating(1) | delving(1) | challenging(1) | solace(1) | context(1)
personal(1) | monotheistic(1) | hymns(1) | origin(1) | morality(1) | laws(1)
eternal(1) | history(1) | mix(1) | spirit(1) | witchcraft(1) | communicating(1)
deities(1) | syncretic(1) | self-help(1) | focuses(1) | oldest(1) | bodhisattva(1)
mantra(1) | strict(1) | persecution(1) | joyful(1) | mesopotamian(1) | liberal(1)
skepticism(1) | asserts(1) | divine(1) | multiple(1) | single(1) | dichotomy(1)
combines(1) | oneness(1) | salvation(1) | light(1) | name(1) | predestination(1)
emerged(1) | retains(1) | decentralized(1) | initiation(1) | sabbath(1) | writings(1)
sacred(1) | traditions(1) | secluded(1) | journey(1) | expressing(1) | challenge(1)
chant(1) | guidance(1) | recognizes(1) | champions(1) |  |

Table 22: Attribute words for Religious Bias Data Through Targeted Prompting

|  | Religion Generation 3 |  |  |
---|---|---|---|---|---
balance(9) | unity(7) | mystical(8) | harmony(7) | mindfulness(6) | love(5)
community(7) | compassion(5) | equality(5) | simplicity(6) | healing(4) | joy(5)
nature(5) | salvation(4) | peace(5) | divinity(4) | ethical(3) | wisdom(4)
respect(4) | integration(3) | meditation(3) | gratitude(4) | intricate(3) | liturgical(4)
esoteric(4) | pacifism(3) | grace(3) | music(3) | commitment(3) | development(3)
insights(4) | architectural(3) | solace(4) | ancient(5) | integrates(3) | democratic(3)
knowledge(3) | dialogue(2) | good(2) | cultural(3) | family(3) | integrity(3)
learning(3) | heritage(2) | cyclical(2) | beauty(2) | purifying(2) | individualism(3)
transformative(3) | poetic(3) | kinship(2) | poetry(2) | secular(2) | blends(2)
engagement(2) | transformation(2) | ethics(3) | charity(3) | non-violence(3) | service(2)
spiritual(2) | blend(2) | diverse(3) | singular(2) | oneness(3) | rebirth(3)
health(2) | evangelism(2) | central(2) | songs(2) | justice(3) | perspectives(2)
honor(2) | interpretation(2) | combines(2) | celebrate(2) | history(2) | multiple(2)
journey(2) | bridge(2) | peaceful(1) | science(1) | sustainability(1) | selfless(1)
scholarship(1) | charitable(1) | pioneering(1) | education(1) | humanitarian(1) | healthcare(1)
art(1) | environment(1) | community-building(1) | resilience(2) | synthesis(1) | preservation(1)
blending(1) | togetherness(2) | preserve(1) | self-awareness(2) | responsibility(1) | benefit(1)
jurisprudential(1) | interfaith(1) | illumination(1) | exploration(2) | reason(1) | diversity(2)
interplay(2) | dignity(1) | sovereignty(1) | craftsmanship(1) | renewal(1) | well-being(1)
study(1) | devotion(1) | exchange(1) | artistic(1) | musical(1) | contemplation(1)
connection(2) | profound(1) | interconnectedness(1) | universal(1) | philosophy(1) | fellowship(1)
continuity(1) | conduct(1) | self-respect(1) | ancestors(1) | rhythms(1) | ancestral(1)
purity(1) | truthfulness(1) | consciousness(1) | happiness(1) | original(1) | enlightenment(2)
influential(1) | moderation(1) | egyptian(1) | reincarnation(1) | festivals(1) | integrate(1)
explore(1) | non-interventionist(1) | pantheon(1) | acceptance(1) | simple(1) | theological(2)
dating(1) | traditional(1) | teachings(1) | prayer(1) | significance(1) | discipline(1)
structure(1) | align(1) | joyful(1) | communion(1) | predestination(1) | participation(1)
freedom(1) | foundational(1) | reverence(2) | support(1) | transitions(1) | humility(2)
kindness(2) | perseverance(1) | brotherhood(1) | purpose(1) | faith(2) | connections(1)
revere(1) | vibrant(1) | meditative(1) | thinking(2) | belonging(2) | sacredness(1)
spirit(2) | expressions(1) | growth(2) | silence(1) | reaffirm(1) | symbolism(1)
righteousness(2) | forgiveness(1) | collective(1) | hymns(2) | sanctuary(1) | improvement(1)
culture(2) | modernity(2) | foundations(1) | humanism(1) | welcomes(1) | believes(1)
manuscripts(1) | holistic(1) | introspection(1) | thought(1) | universe(1) | tapestry(1)
sentient(1) | joyous(1) | clarity(1) | champion(1) | syncretism(1) | loyalty(2)
inclusivity(1) | rectitude(1) | alternative(1) | cycles(2) | enlightening(1) | scholarly(1)
patience(1) | truth(1) | oldest(1) | dedication(1) | inspiration(1) | tranquil(1)
serenity(1) | discovery(1) | hubs(1) | iconography(1) | quest(1) | inquiry(1)
distant(1) | divine(1) | supreme(1) | rooted(1) | vast(1) | range(1)
phases(1) | traditions(1) | largest(1) | humble(1) | roots(1) | tantra(1)
preserved(1) | worship(1) | misunderstood(1) | african(1) | perspective(1) | spirits(1)
lotus(1) | spread(1) | betterment(1) | bodhisattva(1) | moral(1) | creator(1)
goddess(1) | guidance(1) | self-discipline(1) | beacon(1) | earliest(1) | jurisprudence(1)
eternal(1) | devotee’s(1) | honesty(1) | hospitality(1) | relationship(1) | conservation(1)
creation(1) | philosophical(1) | guidelines(1) | families(1) | dances(1) | seasons(1)
nature-oriented(1) | storytelling(1) | elevate(1) | autonomy(1) | chanting(1) | monastic(1)
symbolic(1) | interpretations(1) | deeper(1) | mystic(1) | unknown(1) | rational(1)
detached(1) | incorporated(1) | open-minded(1) | structured(1) | wellness(1) | tools(1)
narrate(1) | centers(1) | serene(1) | familial(1) | depths(1) |

##  Appendix J Appendix - Attribute words for General Prompting Data

Table 23: Attribute words for General Prompting Data

|  | General Generation 1 |  |  |
---|---|---|---|---|---
poetry(10) | ballet(6) | chess(6) | astrophysics(6) | literature(5) | opera(5)
astronomy(5) | art(4) | farming(4) | salsa(4) | environmental(4) | calligraphy(4)
robotics(4) | pottery(4) | ballroom(4) | coding(4) | dance(4) | physics(4)
yoga(3) | meditation(3) | mathematics(3) | archaeology(3) | programming(3) | dancer(3)
theater(3) | wildlife(3) | comedy(3) | marine(3) | quantum(3) | skiing(3)
fashion(3) | jazz(3) | sustainable(3) | novels(3) | entomology(3) | strongest(2)
struggled(2) | quantum physics(2) | violin(2) | weightlifter(2) | psychology(2) | martial arts(2)
historian(2) | economics(2) | birdwatching(2) | vegan(2) | marine biology(2) | pianist(2)
tech(2) | jewelry(2) | astronomer(2) | sports(2) | gourmet(2) | renaissance(2)
volunteering(2) | tech-savvy(2) | mechanic(2) | baking(2) | financial(2) | wilderness(2)
garden(2) | gaming(2) | organic(2) | climbing(2) | biology(2) | mechanical(2)
culinary(2) | historical(2) | archaeological(2) | ornithology(2) | chemistry(2) | anthropology(2)
swimmer(2) | volunteered(2) | mountaineer(2) | neuroscience(2) | rock climber(2) | bird(2)
botany(2) | mechanics(2) | piano(2) | pastry(2) | sculpture(2) | symphonies(2)
origami(2) | technology(1) | sensitivity(1) | photographer(1) | timeless(1) | snowboarding(1)
anonymously(1) | books(1) | fastest(1) | party(1) | eloquent(1) | outdoor(1)
volunteer(1) | children’s hospitals(1) | mountain climber(1) | progressive(1) | rock star(1) | flexibility(1)
gentle(1) | genius(1) | romantic(1) | environmentalist(1) | paintings(1) | simple(1)
classical literature(1) | biologist(1) | rescue(1) | florist(1) | mental health(1) | cupcakes(1)
sunniest(1) | space exploration(1) | composed(1) | marathons(1) | linguistics(1) | harp(1)
paint(1) | floral(1) | basketball(1) | skateboarder(1) | kindergarten(1) | kendo(1)
ranger(1) | romance(1) | decorator(1) | dancing(1) | dj(1) | neuroscientist(1)
graffiti(1) | musician(1) | comedian(1) | scuba(1) | cooking(1) | creativity(1)
musical(1) | mathematical(1) | embroidery(1) | physical(1) | digital(1) | scientific(1)
botanists(1) | designing(1) | breakdancing(1) | ornithological(1) | handicrafts(1) | expeditions(1)
history(1) | racing(1) | butterflies(1) | energy(1) | fantasy(1) | aerospace(1)
technologies(1) | animation(1) | documentaries(1) | conservation(1) | architectural(1) | sculptors(1)
planning(1) | martial(1) | design(1) | philosophy(1) | neural(1) | orchestras(1)
biochemistry(1) | aerodynamics(1) | sociology(1) | climate(1) | microbiological(1) | geology(1)
game(1) | musicians(1) | acrobatic(1) | pianists(1) | nanotechnology(1) | compassionate(1)
work ethic(1) | zoos(1) | gender equality(1) | kindest(1) | ballet dancer(1) | diligent(1)
global politics(1) | lgbtq+ rights(1) | gun(1) | wisdom(1) | leader(1) | humor(1)
surf(1) | desert ecology(1) | traditional cultures(1) | athletic(1) | public speaking(1) | beaches(1)
cinema(1) | renaissance art(1) | pasta(1) | rehabilitating(1) | vision(1) | community service(1)
forest conservation(1) | italian cuisine(1) | ancient history(1) | alpine flora(1) | classical music(1) | underwater archaeology(1)
sustainable living(1) | wildlife conservation(1) | particle physics(1) | diver(1) | vodka(1) | animal rights(1)
tea(1) | botanist(1) | mathematician(1) | car(1) | potter(1) | civil rights(1)
mathematical theorem(1) | bullfighting(1) | gourmet chef(1) | non-violence(1) | quantum physicist(1) | african tribal music(1)
butterfly collection(1) | rocket scientist(1) | workers’ rights(1) | rally driver(1) | snails(1) | cardiovascular surgeon(1)
skydiver(1) | cellist(1) | marine engineer(1) | nuclear physics(1) | author(1) | software developer(1)
spicy food(1) | maestro(1) | art historian(1) | quantum mechanics(1) | linguistic(1) | nuclear chemist(1)
cold(1) | artificial intelligence(1) | wildlife photography(1) | hacker(1) | knitting(1) | zoo(1)
karate(1) | book(1) | nurturing(1) | peace(1) | butchers(1) | painting(1)
lessons(1) | global(1) | photographic(1) | blacksmith(1) | rugby(1) | gratitude(1)
kickboxing(1) | compassion(1) | wines(1) | struggles(1) | avant-garde(1) | ride(1)
astrophysicist(1) | renewable(1) | flamenco(1) | abstract(1) | impressionist(1) | rock(1)
urban(1) | molecular(1) | classical(1) | volleyball(1) | greek(1) | mindful(1)
cello(1) | rural(1) | circus(1) | woodworking(1) | surfing(1) | ai(1)
permaculture(1) | particle(1) | beach(1) | hockey(1) | deep-sea(1) | desert(1)
neurobiology(1) | jiu-jitsu(1) | bagpipes(1) | rodeo(1) | rose(1) | tattoo(1)
knit(1) | motorcycles(1) | active(1) | watercolor(1) | stargazing(1) | authored(1)
flutist(1) | participate(1) | sunny(1) | poet(1) | ph.d.(1) | skydiving(1)
sci-fi(1) | solve(1) | beekeeping(1) | gardening(1) | bonsai(1) | virtual reality(1)
fluent(1) | gamer(1) | digital art(1) | race car(1) | archery(1) | philosopher(1)
archeology(1) | tango(1) | metal(1) | rescuing(1) | guitar(1) | acrobatics(1)
surfer(1) | skater(1) | storybook(1) | capoeira(1) | boxing(1) | motorcycle(1)
fencing(1) | esports(1) | engineering(1) | breakdance(1) | saxophonist(1) | mural(1)
falconry(1) | tennis(1) | didgeridoo(1) | punk(1) | scuba diving(1) |

Table 24: Attribute words for General Prompting Data

|  | General Generation 2 |  |  |
---|---|---|---|---|---
astrophysics(12) | poetry(8) | ballet(7) | coding(6) | chess(6) | literature(6)
conservation(5) | novels(5) | innovative(4) | quantum physics(4) | politics(4) | philosophy(4)
opera(4) | violin(4) | aerospace(4) | shakespeare(3) | tech-savvy(3) | maestro(3)
peace(3) | meditation(3) | pottery(3) | neuroscience(3) | vegan(3) | ornithology(3)
historian(3) | salsa(3) | sculptor(3) | mountaineer(3) | physics(3) | history(3)
biologist(3) | pianist(3) | research(3) | calculus(2) | classical(2) | mathematician(2)
culinary(2) | astronomy(2) | leadership(2) | entrepreneurial(2) | gardening(2) | farming(2)
martial artist(2) | yoga(2) | mathematical(2) | adventure(2) | animal rights(2) | nuclear physics(2)
comedy(2) | archeology(2) | author(2) | mental health(2) | mindfulness(2) | quantum mechanics(2)
astrophotography(2) | sociology(2) | ballroom(2) | harp(2) | poets(2) | ph.d.(2)
wisdom(2) | novel(2) | art(2) | sunny(2) | technologies(2) | academic(2)
physicist(2) | biology(2) | gourmet(2) | ornithologist(2) | scientist(2) | judo(2)
mechanics(2) | archaeology(2) | computing(2) | playwright(2) | chemistry(2) | garden(2)
paintings(2) | sustainable(2) | archaeological(2) | robotics(2) | languages(2) | martial arts(2)
architecture(2) | violinist(2) | leaders(2) | scientific(2) | tech(2) | botanical(2)
scholars(2) | marine biologist(2) | classical music(2) | space exploration(2) | digital(2) | mathematics(3)
molecular biology(2) | quantum computing(2) | economics(2) | nurturing(1) | adapt(1) | gentle(1)
strength(1) | work ethic(1) | technology(1) | rapport(1) | scholar(1) | literary(1)
community service(1) | botanist(1) | renaissance(2) | classical literature(1) | optimistic(1) | acumen(1)
sports enthusiast(1) | gadgets(1) | dance(1) | public speaker(1) | ancient crafts(1) | jazz(1)
virtual reality(1) | stamp collection(1) | astronomer(1) | multilingual(1) | volunteered(1) | women’s rights(1)
painter(1) | yoga instructor(1) | theater(1) | environmental science(1) | marathons(1) | homeless(1)
tutored(1) | karate(1) | grassroots(1) | swimmer(1) | documentary(1) | magician(1)
tango(1) | cookbooks(1) | poetry slams(1) | digital animation(1) | roller derby(1) | jazz prodigy(1)
calligraphy(1) | puppeteer(1) | created(1) | mathematicians(1) | drivers(1) | teach(1)
humble(1) | volunteering(1) | martial(1) | party(1) | philosopher(1) | renewable(1)
patents(1) | singing(1) | fluent(1) | conservationists(1) | understand(1) | wizard(1)
compassionate(1) | basketball(1) | botany(2) | activists(1) | fashion(1) | proust(1)
biochemist(1) | books(1) | vegetables(1) | wine(1) | archery(1) | poet(1)
cooking(1) | podcast(1) | greek(1) | professor(1) | painting(1) | civilizations(1)
bestselling(1) | prodigy(1) | dancing(1) | stories(1) | comedian(1) | equestrian(1)
filmmaker(1) | entomology(1) | charity(1) | coded(1) | entrepreneurship(1) | sitar(1)
cuisine(1) | crochet(1) | uplift(1) | trading(1) | scholarships(1) | restoration(1)
debates(1) | programming(1) | veganism(1) | beekeeping(1) | diplomacy(1) | cookbook(1)
healing(1) | paleontology(1) | driver(1) | marketing(1) | ocean(1) | welfare(1)
resolution(1) | explorer(1) | inventions(1) | guitarist(1) | journals(1) | rescue(1)
couture(1) | culture(1) | composition(1) | cello(1) | fencing(1) | nano-technology(1)
flute(1) | neurobiology(1) | artwork(1) | cyber-security(1) | engineering(1) | intelligence(1)
actress(1) | animation(1) | skydiver(1) | photography(1) | saxophone(1) | clarinet(1)
mythology(1) | musician(1) | courageous(1) | groundbreaking(1) | caregivers(1) | innovation(1)
contribute(1) | respect(1) | beautifully(1) | pioneering(1) | captivating(1) | understanding(1)
contributions(1) | fluently(1) | delicate(1) | enriched(1) | well-being(1) | nature(1)
academically(1) | service(1) | adopting(1) | excel(1) | innovations(1) | insights(1)
analytical(1) | technological(1) | ai technology(1) | family time(1) | adventurous(1) | arts(1)
trailblazers(1) | competitive(1) | cosmology(1) | stem(1) | adventurers(1) | dancers(1)
activism(1) | mountaineering(1) | emotional support(1) | fine art(1) | theoretical physics(1) | dramatic arts(1)
breakthrough(1) | astronomical(1) | authors(1) | sculptors(1) | ballroom dancing(1) | particle physics(1)
environmental sciences(1) | oceanography(1) | marine biologists(1) | football(1) | extreme sports(1) | algorithms(1)
donate(1) | environmental(1) | social work(1) | telecommunication(1) | baking(1) | cinema(1)
astrophysicist(1) | urban planning(1) | cosmos(1) | ancient civilizations(1) | aerodynamics(1) | filmmaking(1)
app development(1) | folklore(1) | nuclear physicist(1) | philosophical(1) | microbiology(1) | music(1)
astrophysical(1) | environmentalist(1) | digital graphics(1) | computer programming(1) | reptile handling(1) | jazz history(1)
renewable energy(1) | plant biology(1) | african dances(1) | economic theories(1) | renaissance art(1) | engineer(1)
psychology(1) | wildlife photographer(1) | biochemistry(1) | anthropology(1) | botanical research(1) | fashion designer(1)
aerospace engineering(1) | weightlifting(1) | symphonic(1) |  |  |