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The purpose of this paper is to analyze and compare the performances of novel roadable personal air vehicle (PAV) concepts that meet established operational requirements with different types of engines.

The vehicle configuration was devised considering the dimensions and operational restrictions of the roads, runways and parking lots in South Korea. A folding wing design was adopted for road operations and parking. The propulsion designs considered herein use gasoline, diesel and hybrid architectures for longer-range missions. The sizing point of the roadable PAV that minimizes the wing area was selected, and the rate of climb, ground roll distance, cruise speed and service ceiling requirements were met. For various engine types and mission profiles, the performances of differently sized PAVs were compared with respect to the MTOW, wing area, wing span, thrust-to-weight ratio, wing loading, power-to-weight ratio, brake horsepower and fuel efficiency.

Unlike automobiles, the weight penalty of the hybrid system because of the additional electrical components reduced the fuel efficiency considerably. When the four engine types were compared, matching the total engine system weight, the internal combustion (IC) engine PAVs had better fuel efficiency rates than the hybrid powered PAVs. Finally, a gasoline-powered PAV configuration was selected as the final design because it had the lowest MTOW, despite its slightly worse fuel efficiency compared to that of the diesel-powered engine.

Although an electric aircraft powered only by batteries most capitalizes on the operating cost, noise and emissions benefits of electric propulsion, it also is most hampered by range limitations. Air traffic integration or any safety, and noise issues were not accounted in this study.

Aircraft sizing is a critical aspect of a system-level study because it is a prerequisite for most design and analysis activities, including those related to the internal layout as well as cost and system effectiveness analyses. The results of this study can be implemented to design a PAV.

This study can contribute to the establishment of innovative PAV concepts that can alleviate today’s transportation problems.

This study compared the sizing results of PAVs with hybrid engines with those having IC engines.

The purpose of this paper is to present deprivation in urban Brazil in a multidimensional perspective with dimensions related to household’s objective information, assets in the household, subjective evaluation concerning the dwelling and expenses.

The author used factorial analysis applied to the Brazilian Household Budget Survey. Most dimensions showed a positive correlation with income, while for others it was not observed any significant difference between income ranges. Some types of deprivation specially touched low-income households, while other dimensions differentiated middle-income households, or even higher income households. The author applied a fuzzy perspective to define deprivation membership in each dimension with the use of a modified logistic function. The author observed that households with similar income faced different levels of deprivation in many dimensions.

The author showed that there were significant differences in household’s expense preferences and profiles linked to these findings. Households with high levels of food deprivation relatively spend more on household’s rent, taxes and services, indicating that shelter and then food in the household are the very basic goods. Larger relative expenses with food in the household indicated higher levels of deprivation in all other dimensions, indicating that due to these higher food expenditures, the households could not overcome the deprivation in other dimensions. Households that spend more on smoke and gambling faced higher deprivation in most dimensions, suggesting different expenses priorities, less household oriented.

To the best of the knowledge, this is the first attempt to link multidimensional deprivation and expenses profile for Brazilian data.

The purpose of this paper is to present the development of an optimal design framework for high altitude long endurance solar unmanned aerial vehicle. The proposed solar aircraft design framework provides a simple method to design solar aircraft for users of all levels of experience.

This design framework consists of algorithms and user interfaces for the design of experiments, optimization and mission analysis that includes aerodynamics, performance, solar energy, weight and flight distances.

The proposed sizing method produces the optimal solar aircraft that yields the minimum weight and satisfies the constraints such as the power balance, the night time energy balance and the lift coefficient limit.

The design conditions for the sizing process are given in terms of mission altitudes, flight dates, flight latitudes/longitudes and design factors for the aircraft configuration.

The framework environment is light and easily accessible as it is implemented using open programs without the use of any expensive commercial tools or in-house programs. In addition, this study presents a sizing method for solar aircraft as traditional sizing methods fail to reflect their unique features.

Solar aircraft can be used in place of a satellite and introduce many advantages. The solar aircraft is much cheaper than the conventional satellite, which costs approximately $200-300m. It operates at a closer altitude to the ground and allows for a better visual inspection. It also provides greater flexibility of missions and covers a wider range of applications.

This study presents the implementation of a function that yields optimized flight performance under the given mission conditions, such as climb, cruise and descent for a solar aircraft.

Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.

Global issues on the environment, such as climate change, air pollution and carbon monoxide emission, are the primary concerns in any part of the world. The purpose of this paper is to construct a conceptual framework for the travel behavior performance of a commuter, and it is expected to mitigate air pollution from vehicle emission and to promote smart mobility on the road.

From the extensive literature review, the conceptual framework for the travel behavior performance of a commuter has been developed and is supported by the theory of interpersonal behavior (TIB), whose functions are attitude, social factor, affect and habit. In the present paper, attitude is conceptualized by four predictors, namely confidence in driving, green environment, social responsibility and deviation in driving. The social factor is characterized by subjective norms, social status and digitalization. Affect factor is conceptualized by accidents and damages, road infrastructure, and weather conditions. The mental block in following the ancestor’s way of owning a personal vehicle is the predictor for the habit.

One of the major contributors to environmental damages is road traffic. Notably, vehicle emissions are on the rise every year due to the increase of reliance on vehicles, and there is no alternative to this issue. Although Malaysia has a well-organized infrastructure with effective digitalized technology on the road for the transport system, there is severe traffic congestion in Klang Valley, Kuala Lumpur, because of a lack of travel plan behavior during peak hours. If the road commuters give the predictors constructed in the proposed conceptual framework the highest importance, then there will be much relief to traffic congestion on the road.

Since the present study focuses on the conceptualization of an urban travel behavior model (UTBM), and also highlights the synchronization of the proposed framework with the management theory, the results are expected after the primary survey based on the cross-sectional study will be conducted.

The identification of the suitable predictors for the UTBM toward the travel behavior performance of a commuter is the real novelty of the present study. Also, the cause and effect relationships of different predictors in terms of path directions of the proposed research framework are the highlights of the study. Further, the predictors in the proposed framework and the TIB have been synchronized with operational definitions, which are the original contributions of the present study, which will enhance the sustainable environmental development for the society as a whole.