Dear Alireza,
Below is a list of the research areas that a sample of design researchers
claimed to be working in. 
Best wishes,
Terry
____________________

Dr. Terence Love, FDRS, AMIMechE, PMACM

Director Design-focused Research Group, Design Out Crime Research Group
Researcher, Digital Ecosystems and Business Intelligence Institute
Associate,  Planning and Transport Research Centre
Curtin University, PO Box U1987, Perth, Western Australia 6845
Mob: 0434 975 848, Fax +61(0)8 9305 7629, [log in to unmask]
Visiting Professor, Member of Scientific Council
UNIDCOM/ IADE, Lisbon, Portugal
Honorary Fellow, Institute of Entrepreneurship and Enterprise Development
Management School, Lancaster University, Lancaster, UK
____________________

19th century literature and art
3D modelling assistance
accessibility
access grid
activism in design/cultural
adaptive expertise
advanced qualitative research methodologies
aerospace design/architecture
aesthetic
aesthetics of design from a philosophical point of view
aesthetics, research (by which I mean researching the theory of research)
Al in design process
alternative technology and innovation
analogical reasoning and design
analysis of design processes
analysis of language
analytic aesthetics
analytical techniques
anthropological theory
anthropology
applications and implications for studio pedagogy
applied anthropology
applied psychology
Arabic typography
architectural and urban education and theory
architectural design & practice
architecture
architecture/design: programming
Art and Design education
art history
art/design
artefact/textiles
artefacts (for generating understanding of the design space and for "use" in
a broad sense
augmented reality
bamboo: as a development resource and a future material for human use:
"post-mining human civilisation" or "post-hydrocarbon culture", an idea
under development in India (in some limited circles)
behavior
branding structures
built heritage
business
careers
cars
case study
case-based design
certification
children's books illustration
china
Christian
circularity/cybernetics
cognition and design
cognition/perception
cognitive engineering of human, technology interfaces
cognitive psychology / cognitive science
cognitive risk tolerance: conceptual and practical implications
collaborative design
collaborative design research
collaborative influences on the design process
colour
comics
communication
communication in design processes
complexity of design activity
computer aided design (systems and application)
concept generation
consumer anthropology
consumer perceptions
consumption
contemporary and media archaeologies
contemporary art
coordination and collaboration in groups
craft
crafts and design for development: critical tools for solving poverty in
India and elsewhere
creative processes and design
creativity
creativity and computers in design
critical thinking
critics
cross cultural design
crossfield between designers
CSCW (computer supported collaborative working)
cultural analysis
cultural analysis of design
cultural anthropology
cultural historical aspects of design
cultural product concepts
culture
culture and design
culture theories
customisation
decision theory and techniques
design
design & innovation processes
design aesthetics
design and branding
design and creation of economic value
design and culture
design and development
design and digital media
design and disability
design and emotion
design and ethnic groups
design and information technology
design and interpretation
design and marketing
design and material
design and metaphor
design and organizational learning
design and sustainability (not environmental design, please)
design and the body
design and the environment
design and the internet
design and voice
design as scaffolding
design briefing/programming
design cognition
design competence
design concepts
design construction
design consultancy business
design criticism
design development based on local cultures/heritage
design discourse
design education
design education of multilingual/multicultural students
design education: building new schools for sector specific design education
(crafts and bamboo)
design effectiveness
design ethics
design ethnography
design evaluation
design for accessibility
design for all
design for healthcare
design for sustainability
design for the people
design history
design improvisations
design in built heritage
design information (visual analytics)
design innovation
design knowledge & expertise
design knowledge and context-of-use
design management
design management education
design management research
design methodology
Design methods (e.g. methodic design, TRIZ, value analysis etc.)
design of diving equipment
design of learning with ICT
design of product/service systems
design pedagogies
design philosophy
design planning
design policy
design process
design process mapping
design reasoning
design representations
design research
design research methods
design research methods for designers
Design science
design strategy
design support or promotion
design teacher, 
design teaching
design teaching (basic level)
design theories
design theory of information technology
design thinking
design versus research
design visualisation
design/product semantics
designer behaviours
designer personality
designerly theorization
designers
designing to improve comfort, safety and well-being
developing countries
development of physiological methods in design
didactics in artefacts conception and use
differences between words and images
digital art and design
digital design repositories
digital museums and archives
discourse analysis
distance learning (and web delivery)
doctoral education
doctoral training
Domain analysis
Drawing
dynamic interior environments
eco design
education
educational institutions
e-learning
emotional ergonomics
emotions in design
emotions in/and subject-object relations
empathic values
empirical studies
enabler
engineering design
enlightenment
environment
environmental design
epistemology relative to design
ergonomics
ethical experience
ethics
ethnographic methodology
ethnography
ethnography
Europe
evaluation
evolutionary approaches in / for design
evolvable and adaptive intelligent systems design
exhibitions
experience
experimental design & art
expert design behaviour and reasoning
expertise and design
exporting creativity
facilitation and coaching
feminism and design
feminism
form generation
formal systems (logic) in design
foundations for doctoral research
functional relevance and usability implications for design of technology
future
generative design
generative research
geometry and structure
globalization
graphic design
graphic design (design processes)
graphic design education
graphic design history
graphic design political
graphics/social
handicrafts
health and design (vulnerable populations
Hellenic Greek arts
history
history and philosophy of science
history and theory of architecture
history of aesthetics
history of industrial design in the periphery
history of mentality
history of visual communication
housing layout & density and passive solar design
human centered design
human factors and ergonomics
human failures and limitations
human modelling CAD systems
human-centered innovation methodology
ideological design, sub-cultural inspired design
illustration
image and text
inclusive design
industrial design
industrial design education
Industrial design research
Industry
information
information design
information processing and knowledge management in design
information technology
information visualization
innovation
innovation management
innovation methods
innovative design
innovative technology and accessibility for the elderly & disabled
integrated product development, methodologies and tools
integrating design
inter/multidisciplinary collaboration in design
interaction
interaction design
interaction design research
interaction design, specifically new media, mixed media and interactive
visualization
interactive media
Interdisciplinarity
interdisciplinary
interface design,
interiors and furniture and their 4000 years history/evolution
internet culture
issues connected to cultural sociology
IT enabled development with design
kansei engineering
knowing in design
knowledge acquisition (i.e. cognitive studies)
knowledge based engineering (capture and formalisation of design rules)
knowledge construction
knowledge development
knowledge exchange between design practise & academia
knowledge management
knowledge_for and knowledge_of
knowledge-based economy
Kondratieff's cycles
language and communication as related to typography (visible language)
LCD-life cycle design
learning
light
Lisbon
local design
management
management of innovation, design and NPD
market creation
marketing
material culture
material thinking
materials
materials and design practice
measurement of the amount of relativistic information
mechatronics
medical products
medical technology & innovation, E-health
mental models in design teams 
method
method and process
methodological approaches in design
methodologies
methodology
methods & tools for concept development
methods & tools for idea generation
methods of design research
mixed-mode practice
multilevel psychological model of risk tolerance
multimodal-multisensory monitoring
national design policies
new industrial contexts and new design scenarios
new product development
of "public space"
ontology of artefacts
ontology
optimisation
outside the obvious fields of information design
participation
participatory action research
participatory design
participatory design (cooperative design space)
participatory design research
pattern and decoration
patterning
perception
perception design
perception enhancement
performativity, place, space
PhD in communication design
phenomenology
phenomenology in architecture, theory, criticism, rediscovered relevance
philosophy
philosophy of design
philosophy of language
photography image
politicians and business-organisations
popular
post-structuralism
practice
practice design innovation
practice-based
practice-based methodology
practice-based research
practice-led research
problem solving
process facilitation
process/methods
product design
product design and textiles
product pleasure
product semantics
product taste, visual research
product/graphic
product/service definition
professional software development practice
psychology of art
qualitative research methods for design
qualitative user research
real time rendering
reflection
reflective processes and methods
reflexive capability
regional culture
regional design
relation between digital and physical material, process influences, skills
needed
relational
religion
religion and design
representation
representation abstractions
representations
research
research and education (integration of theory in practice, research based
design, and design based research)
research community development
research management
research methodology & education
research methods
scenario-building in design
science of profession
science
semantics
semiotics
semiotics (and problems of user-research, reception research)
semiotics and discourse analysis
semiotics in/and design
sensorial interfaces
situations, communication technology
skiamorph skeumorph
social & economic development by design
social and cultural human factors
social contexts
social design
social interaction
social network visualization
social responsibility
socialness of artefacts
sociocultural aspects of design
sociology
sociology of design
software design
space and place
specific issues for re-examination, currently focussing on: the discourse of
beauty in the architecture studio
strategic design
strategic design planning
strategic planning
strategies of expert designers
strategy
student experience
studio instruction
style cognition
subject-object relationships in the architectural studio
supply chain integration
sustainability
system design
systemic design and services
systemic design
systems theories related to design
systems thinking
tacit knowledge
teaching
technical communication (drawing rules, icons applications)
technological and social change
technologies and processes of construction
technology and instruction: potential and problems
technology studies, mobile multimedia messaging, picture sharing
telepresence experience/telepistemology
textile art and modern technology
textile design
textiles
the aged
the application of perception science or cognitive science to design
the concept of research
the social construction of form ideals (formbild)
theory
theory of design
theory of innovation
theory/design
third world
timeless, -ness
tools for design
town planning
traditional textile arts
traditions
typography
ubiquitous computing
undesigned
Planning
usability
usability of information/user testing
user centered design
user centred design research
user experience
user interface design
user needs
user participation
user-centered design research methods
user-centred design
user-designer experience
value
value chain
values
vehicle ergonomics
visual
visual communication
visual culture
visual design research methods
visual studies
visual thinking
visualising non-geometric
welfare design
word & image relations
workshops (for generating understanding of the design space)
workspace