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The purpose of this paper is to present a novel approach based on the artificial bee colony (ABC) algorithm aiming to achieve maximum acceleration and maximum endurance for morphing unmanned aerial vehicle (UAV) design.

Some of the most important issues in the design of UAV are the design of thrust system and determination of the endurance of the UAV. Although propeller selection is very important for the thrust system design, battery selection has the utmost importance for the determination of UAV endurance. In this study, the calculations of maximum acceleration and endurance required by ZANKA-II during the flight are considered simultaneously. For this purpose, a model based on the ABC algorithm is proposed for the morphing UAV design, aiming to achieve the maximum acceleration and endurance. In the proposed model, the propeller diameter, propeller pitch and battery values used in morphing UAV's power system design are selected as the input parameters; maximum acceleration and endurance are selected as the output parameters. To obtain the maximum acceleration and endurance, the optimum input parameters are determined through the ABC algorithm-based model.

Considerable improvements on maximum acceleration and endurance of morphing UAV with ABC algorithm-based model are obtained.

The endurance and acceleration due to the thrust are two separate parameters that are not normally proportional to each other. In this study, optimization of UAV’s endurance and acceleration is considered with equal importance.

Using artificial intelligence techniques causes fast and simple optimization for determination of UAV’s endurance and acceleration with equal importance. In the simulation studies with ABC algorithm, satisfactory results are obtained.

The results of the study have showed that the proposed approach could be an alternative method for UAV designers.

Providing a new and efficient method saves time and reduces cost in calculations of maximum acceleration and endurance of the UAV.

The purpose of this paper is to create an endurance index of housing investor sentiment and use it to forecast housing stock returns. This study performs not only in-sample and out-of-sample forecasting, like many previous studies did, but also a true forecasting by using all lag terms of independent variables. In addition, an evaluation procedure is applied to quantify the quality of forecasts.

Using a binomial probability distribution model, this paper creates an endurance index of housing investor sentiment. The index reflects the probability of the high or low stock price being the close price for the Philadelphia Stock Exchange Housing Sector Index. This housing investor sentiment endurance index directly uses housing stock price differentials to measure housing investor reactions to all relevant news. Empirical results in this study suggest that the index can not only play a significant role in explaining variations in housing stock returns but also have decent forecasting ability.

Results of this study reveal the considerable forecasting ability of the index. Monthly forecasts of housing stock returns have an overall accuracy of 51 per cent, while the overall accuracy of 8-quarter rolling forecasts even reaches 84 per cent. In addition, the index has decent forecasting ability on changes in housing prices as suggested by the strong evidence of one-direction causal relations running from the endurance index to housing prices. However, extreme volatility of housing stock returns may impair the forecasting quality.

The endurance index of housing investor sentiment is easy to construct and use for forecasting housing stock returns. The demonstrated predictability of the index on housing stock returns in this study can have broad implications on housing-related business practices through providing an effective forecasting tool to investors and analysts of housing stocks, as well as housing policy-makers.

Despite different investor sentiment proxies suggested in the previous studies, few of them can effectively predict stock returns, due to some embedded limitations. Many increases and decreases inn prices cancel out each other during the trading day, as many unreliable sentiments cancel out each other. This dynamic process reveals not only investor sentiment but also resilience or endurance of sentiment. It is only long-lasting resilient sentiment that can be built in the closing price. It means that the only feasible way to use investor sentiment contained in stock prices to forecast future stock prices is to detach resilient investor sentiment from stock prices and construct an index of endurance of investor sentiment.

The purpose of this paper is finding the optimal geometric parameters and developing of a method for optimizing a light unmanned aerial vehicle (UAV) wing, maximizing, at the same time, its endurance with the assumed parameters of aircraft mission.

The research is based on the experience gained by the author’s contribution to the project of building medium-altitude, long-endurance class, light UAV called “Samonit”. The author was responsible for the structure design, wind tunnel tests and flight tests of the “Samonit” aircraft. Based on the experience, the author was able to develop an optimization process considering various disciplines involved in the whole aircraft design topics such as aerodynamics, flight mechanics, structural stiffness and weight, aircraft stability and maneuverability. The presented methodology has a multidisciplinary nature, as in the process of optimization both aerodynamic aspects and the influence of wing geometric parameters on the wing structure and weight and the aircraft payload were taken into account. The optimal wing configuration was obtained using the genetic algorithms.

As a result, a set of wing geometrical parameters has been obtained that allowed for achieving twice as long endurance as compared with the initial one.

Using the methodology presented in the paper, an aircraft designer can easily find the optimum wing configuration of a designed aircraft, satisfying the mission requirements in a best way.

An original procedure has been developed, based on the actual design, wind tunnel tests and numerical calculations of “Samonit” aircraft, enabling the determination of optimum wing configuration for a small unmanned aircraft.

This paper aims to determine the influence of physical ability on initial emergency response performance among emergency response teams.

In an emergency incident, emergency responders are involved in vigorous physical activities. Previous attempts have demonstrated that job performance of emergency responders depends a great deal on their ability to perform strenuous physical activity. This paper examines the influence of physical ability namely weight, height, and cardiovascular endurance on emergency response performance among fire fighting teams in Malaysia. Emergency response performance was defined as team member's speed in responding to emergency situations. Data on team member's physical ability and emergency response time were collected for the duration of five months. The distance from the waiting room to the fire truck in each selected fire station was used to measure performance.

This study found that the team with higher average weight and cardiovascular endurance level had better initial response to emergency situations, contrary to the research hypothesis. But it is speculated that the relationship could be further understood by considering the proportion of fat in the body. The relationship between cardiovascular endurance and initial emergency response performance further validates and justifies the use of physical fitness test as a criterion for job performance of fire fighters.

This paper offers empirical evidence of emergency response performance in Malaysia. Specifically, it presents findings on the influence of physical ability measures on initial emergency response performance from a team perspective. In addition, the emergency response performance was measured by the distance traveled by the responders, which serves as a meaningful performance indicator.

In recent years, high‐altitude/long‐endurance airship platforms have generated great interest as a means to provide communications and surveillance capabilities. The purpose of this paper is to develop a model for airship conceptual design and help provide insight into the viability of high‐altitude/long‐endurance airships.

A configuration analysis model with the consideration of pressure difference, temperature difference, and helium purity, etc. was developed. The influences of the airship payload, size and area required of solar cell with environment and operation parameters, such as operation latitude, pressure difference, temperature difference, helium purity, seasons, latitude, and wind speed, etc. were analyzed.

The results show that the area of solar cell required for stratospheric airship is very large under the condition of low altitude, high latitude, wind, and in winter, etc. which might make the design of high‐altitude/long‐endurance airship an elusive goal. They also show that the solar cell efficiency is the key technology in the control of solar cell area required for airships, and the technology advances in regenerative fuel cells and propeller efficiency have significant effects among on the airship payload, size, and solar cell area required for airship.

The paper analyses the energy balance of the high‐altitude/long‐endurance airship.

THE method used at present in fatigue testing aircraft joints and components by applying cycles of constant stress amplitude of a magnitude considered to be the most damaging is based on the assumption that Miner's cumulative damage rule, Σ(n/N)&equals l, holds good. This rule is known to be true only under certain conditions which may not apply to those under which fatigue damage is accumulated in aircraft.

The purpose of this review is to provide a comprehensive summary, for both experts and non‐experts, of new findings on interactions among diet, genes, and exercise in determining the risk for chronic disease.

The present review focuses on the key role of exercise in modulating the ratio of muscle fiber types and the resulting effects on overall health.

Exercise and a diet rich in omega‐3 (n‐3) fatty acids modulate human gene expression and lower the risk for chronic disease. Emerging evidence, synthesized here, shows that a family of gene regulatory proteins, the PPAR (peroxisome proliferator‐activated receptor) transcription factor family, regulates the synthesis of human muscle fibers and thereby affects glucose metabolism and the risk for obesity, diabetes, and heart disease. Dietary fatty acids, in particular n‐3 polyunsaturated fatty acids, act on PPAR family members, and thereby enhance the synthesis of specific muscle fiber types. Human muscle fibers contain a heterogeneous mix of slow‐oxidative, fast‐oxidative, and fast‐glycolytic muscle fibers. At the extremes of the spectrum, low‐oxidative fibers, important for endurance activities, rely on a complete oxidation of sugars as well as fats for energy, and are associated with high insulin sensitivity. In contrast, fast‐glycolytic fibers, important for short, intense exercise, predominantly use a quick, but only partial breakdown of sugars (glycolysis) for energy. Not surprisingly, sprinters have more fast‐glycolytic fibers, while endurance athletes have more slow‐oxidative fibers. The relative ratio of these different fiber types, in part genetically fixed and in part respondent to diet and exercise, determines not only what type of activities an individual performs best, but also affects the risk for chronic disease. Recent research has identified correlations between muscle fiber type and PPAR type as well as between even modest levels of endurance training and a lowering of the risk for insulin resistance, obesity, diabetes, and heart disease.

This review synthesizes recently discovered mechanisms into a framework supporting the conclusion that even moderate levels of endurance exercise, combined with a sufficient intake of n‐3 fatty acids, lower the risk for chronic disease.

This article provides accessible and comprehensive information to researchers, nutritionists, and consumers who are interested in using lifestyle management (such as exercise and diet) to lower the risk for chronic disease.

When comparing and contrasting different types of fixed-wing military aircraft on the basis of an energetic efficiency figure-of-merit, unmanned aerial vehicles (UAVs) dedicated to tactical medium-altitude long-endurance (MALE) operations appear to have significant potential when hybrid-electric propulsion and power systems (HEPPS) are implemented. Beginning with a baseline Eulair drone, this paper aims to examine the feasibility of retro-fitting with an Autarkic-Parallel-HEPPS architecture to enhance performance of the original single diesel engine.

In view of the low gravimetric specific energy performance attributes of batteries in the foreseeable future, the best approach was found to be one in which the Parallel-HEPPS architecture has the thermal engine augmented by an organic rankine cycle (ORC). For this study, with the outer mould lines fixed, the goal was to increase endurance without increasing the Eulair drone maximum take-off weight beyond an upper limit of +10%. The intent was to also retain take-off distance and climb performance or, where possible, improve upon these aspects. Therefore, as the focus of the work was on power scheduling, two primary control variables were identified as degree-of-hybridisation for useful power and cut-off altitude during the en route climb phase. Quasi-static methods were used for technical sub-space modelling, and these modules were linked into a constrained optimisation algorithm.

Results showed that an Autarkic-Parallel-HEPPS architecture comprising an ORC thermal energy recovery apparatus and high-end year-2020 battery, the endurance of the considered aircraft could be increased by 11%, i.e. a total of around 28 h, including de-icing system, in-flight recharge and emergency aircraft recovery capabilities. The same aircraft with the de-icing functionality removed resulted in a 20% increase in maximum endurance to 30 h.

Although the adoption of Series/Parallel-HEPPS only solutions do tend to generate questionable improvements in UAV operational performance, combinations of HEPPS with energy recovery machines that use, for example, an ORC, were found to have merit. Furthermore, such architectural solutions could also offer opportunity to facilitate additional functions like de-icing and emergency aircraft recovery during engine failure, which is either not available for UAVs today or prove to be prohibitive in terms of operational performance attributes when implemented using a conventional PPS approach.

This technical paper highlights a new degree of freedom in terms of power scheduling during climbing transversal flight operations. A control parameter of cut-off altitude for all types of HEPPS-based aircraft should be introduced into the technical decision-making/optimisation/analysis scheme and is seen to be a fundamental aspect when conducting trade-studies with respect to degree-of-hybridisation for useful power.

This paper aims to increase understanding of how the strength of the relationship between service failure-induced customer anger and revenge intentions might be influenced by attitudinal moderators that are both within and outside the realm of the service firm’s control. Drawing on past research, the authors hypothesize that customers’ perceptions of the corporate reputation and silent endurance constitute boundary conditions of the relationship between service failure-related customer anger and revenge intentions.

In line with past service failure research, the authors test the hypotheses using a scenario-based online experiment with 243 participants.

This research reaffirms the positive relationship between anger and revenge intentions and finds support for the hypothesized boundary conditions; customers with better corporate reputation perceptions and higher levels of silent endurance express weaker revenge intentions than those with poor corporate reputation perceptions and lower levels of silent endurance.

This research offers unique insights into how service organizations can buffer the detrimental effects of service failure-induced customer anger.

IN aircraft construction, until about fifteen years ago, the customary static method of stressing generally also provided for an adequate fatigue strength. This does not now apply for various reasons (e.g. increased flight speeds, use of high‐strength materials with changed fatigue properties). It is, therefore, necessary to establish design rules which take account of more recent knowledge; which variables are to be specially considered, and what their importance is in a particular case, becomes clear from fatigue tests which, to a considerable extent, cater for the peculiar loading conditions of flight (service endurance tests or programme‐loading tests). The principle of these tests was established in the DVL (1938 to 1941) and it is now in general use in automobile design for determining the relation between fatigue strength and endurance (life function) as in many cases of service failures a very good agreement with these tests can be observed.