Application of virtual flight test framework with derivative design optimization

2018 ◽  
Vol 90 (9) ◽  
pp. 1445-1463
Author(s):  
Hyeong-Uk Park ◽  
Joon Chung ◽  
Ohyun Kwon

Purpose The purpose of this paper is a development of a virtual flight test framework with derivative design optimization. Aircraft manufactures and engineers have been putting significant effort into the design process to lower the cost of development and time to a minimum. In terms of flight tests and aircraft certification, implementing simulation and virtual test techniques may be a sufficient method in achieving these goals. In addition to simulation and virtual test, a derivative design can be implemented to satisfy different market demands and technical changes while reducing development cost and time. Design/methodology/approach In this paper, a derivative design optimization was applied to Expedition 350, a small piston engine powered aircraft developed by Found Aircraft in Canada. A derivative that changes the manned aircraft to an Unmanned Aerial Vehicle for payload delivery was considered. An optimum configuration was obtained while enhancing the endurance of the UAV. The multidisciplinary design optimization module of the framework represents the optimized configuration and additional parameters for the simulator. These values were implemented in the simulator and generated the aircraft model for simulation. Two aircraft models were generated for the flight test. Findings The optimization process delivered the UAV derivative of Expedition E350, and it had increased endurance up to 21.7 hours. The original and optimized models were implemented into virtual flight test. The cruise performance exhibited less than 10 per cent error on cruise performance between the original model and Pilots Operating Handbook (POH). The dynamic stability of original and optimized models was tested by checking Phugoid, short period, Dutch roll and spiral roll modes. Both models exhibited stable dynamic stability characteristics. Practical implications The original Expedition 350 was generated to verify the accuracy of the simulation data by comparing its result with actual flight test data. The optimized model was generated to evaluate the optimization results. Ultimately, the virtual flight test framework with an aircraft derivative design was proposed in this research. The additional module for derivative design optimization was developed and its results were implemented to commercial off-the-shelf simulators. Originality/value This paper proposed the application of UAV derivative design optimization for the virtual flight test framework. The methodology included the optimization of UAV derivative utilizing MDO and virtual flight testing of an optimized result with a flight simulator.

2019 ◽  
Vol 91 (6) ◽  
pp. 886-892
Author(s):  
Agnieszka Kwiek

Purpose The purpose of this paper is to present the results of a conceptual design of Martian aircraft. This study focuses on the aerodynamic and longitudinal dynamic stability analysis. The main research questions are as follows: Does a tailless aircraft configuration can be used for Martian aircraft? How to the short period characteristic can be improved by side plates modification? Design/methodology/approach Because of a conceptual design stage of this Martian aircraft, aerodynamic characterises were computed by the Panukl package by using the potential flow model. The longitudinal dynamic stability was computed by MATLAB code, and the derivatives computed by the SDSA software were used as the input data. Different aircraft configurations have been studied, including different wing’s aerofoils and configurations of the side plate. Findings This paper presents results of aerodynamic characteristics computations and longitudinal dynamic stability analysis. This paper shows that tailless aircraft configuration has potential to be used as Martian aircraft. Moreover, the study of the impact of side plates’ configurations on the longitudinal dynamic stability is presented. This investigation reveals that the most effective method to improve the short period damping ratio is to change the height of the bottom plate. Practical implications The presented result might be useful in case of further design of the aircrafts for the Mars mission and designing the aircrafts in a tailless configuration. Social implications It is considered by the human expedition that Mars is the most probable planet to explore. This paper presents the conceptual study of aircraft which can be used to take the high-resolution pictures of the surface of Mars, which can be crucial to find the right place to establish a potential Martian base. Originality/value Most of aircrafts proposed for the Mars mission are designed in a configuration with a classic tail; this paper shows a preliminary calculation of the tailless Martian aircraft. Moreover, this paper shows the results of a dynamic stability analysis, where similar papers about aircrafts for the Mars mission do not show such outcomes, especially in the case of the tailless configuration. Moreover, this paper presents the results of the dynamic stability analysis of tailless aircraft with different configurations of the side plates.


2017 ◽  
Vol 16 (2) ◽  
pp. 92-105 ◽  
Author(s):  
Joon-heon Song

Purpose The purpose of this study is to explore the essential cause for the policy failure of Trade Adjustment Assistance (TAA) in South Korea. Design/methodology/approach To substantiate the claims made for the failure of the policy, this paper focuses on the differences in policy preferences among the government ministries and agencies involved in TAA. Findings The failure in the TAA policy, according to this study, was attributed to the conflicts and miscoordination arising from the differences in policy preferences among government ministries and agencies. To rectify this failure, the South Korean government had to revise its laws and regulations several times over a short period. Originality/value Drawing on the analytical framework of the literature on policy failure, this paper examines the causal relationships between outcomes of TAA policy and the conflicts or miscoordination among government bodies at each stage: initiatives and planning, implementation and operation of the policy.


2016 ◽  
Vol 20 (4) ◽  
pp. 195-198 ◽  
Author(s):  
Richard Seymour ◽  
Michael Murray

Purpose There is increasing evidence that participation in various art forms can be beneficial for health and well-being. The purpose of this paper is to examine the impact of participating in a poetry reading group on a group of older residents of an assisted living facility. Design/methodology/approach Six poetry sessions, each on a different theme, were conducted with a group of volunteer participants. These sessions, those of pre- and post-study focus groups and interviews with the group facilitator and staff contact were audio-recorded. The transcripts of the recordings were then subjected to a thematic analysis. Findings Overall the participants were enthused by the opportunity to participate in the project and the benefits were confirmed by the support staff. In addition, reading poetry on particular themes promoted different types of discussion. Research limitations/implications The number of participants in this study was small and the study was conducted over a short period of time. Practical implications This paper confirms the impact of poetry reading for older people. The challenge is to explore this impact in more detail and over community as well as residential settings. Originality/value This paper is the first empirical report on the value of poetry reading for older people.


2018 ◽  
Vol 35 (10) ◽  
pp. 12-14 ◽  
Author(s):  
Sarika Sawant

Purpose Crowd funding is a method to raise funds for a specific cause or project by asking a large number of people to donate money, usually in small amounts, and usually during a relatively short period, such as a few months. This paper aims to explore the global as well as Indian crowd funding platforms and literature as well to find out the success stories of crowd funding. Design/methodology/approach General literature was reviewed. Various crowd funding platforms were scanned, especially Indian, to find the successful crowd funding stories. Findings It was found that plenty of crowd funding initiatives have been taken in India, especially to build libraries, to decorate libraries, for collection development, to provide services, etc. Nongovernmental organizations/trusts are the ones who are undertaking these initiatives. There is a need to create awareness of such activities by experienced library professionals/nonprofessionals who have done crowd funding and for them to share their experiences and practices of crowd funding among other professionals, so that others can also explore such methods. Originality/value This paper promptly presents the Indian crowd funding initiatives and the success stories.


2019 ◽  
Vol 91 (3) ◽  
pp. 428-436 ◽  
Author(s):  
Agnieszka Kwiek

Purpose The purpose of this research is a study into a mathematical approach of a tailless aircraft dynamic stability analysis. This research is focused on investigation of influence of elevons (elevator) on stability derivatives and consequently on the aircraft longitudinal dynamic stability. The main research question is to determine whether this impact should be taken into account on the conceptual and preliminary stage of the analysis of the longitudinal dynamic stability. Design/methodology/approach Aerodynamic coefficients and longitudinal stability derivatives were computed by Panukl (panel methods). The analysis of the dynamic stability of the tailless aircraft was made by the Matlab code and SDSA package. Findings The main result of the research is a comparison of the dynamic stability of the tailless aircraft for different approaches, with and without the impact of elevator deflection on the trim drag and stability derivatives. Research limitations/implications This paper presents research that mostly should be considered on the preliminary stage of aircraft design and dynamic stability analysis. The impact of elevons deflection on the aircraft moment of inertia has been omitted. Practical implications The results of this research will be useful for the further design of small tailless unmanned aerial vehicles (UAVs). Originality/value This research reveals that in case of the analysis of small tailless UAVs, the impact of elevons deflection on stability derivatives is bigger than the impact of a Mach number. This impact should be taken into consideration, especially for a phugoid mode.


2018 ◽  
Vol 12 (3) ◽  
pp. 300-322 ◽  
Author(s):  
Zaiyu Huang ◽  
Candy Lim Chiu ◽  
Sha Mo ◽  
Rob Marjerison

Purpose The purpose of this paper is to develop initial evidence about the nature and features of crowdfunding in China, given it is largely unregulated regulatory frameworks. Design/methodology/approach The paper used extensive desk research using data collected from the public and private sectors, after which the data was analyzed parallel to existing academic literature, that is, institutional context by Bruton et al. (2014). This paper uncovered patterns of development, profiling crowdfunding platforms, examining the regulatory landscape and providing antecedents of successful crowdfunding projects in China. Findings When the traditional financial markets are hard to reach, micro, small and medium enterprises (MSMEs) were starved for capital. Crowdfunding can play a major role in funding and risk sharing. It is an innovative and dynamic vehicle for MSMEs as well as enthusiastic investors in China. Since its initial introduction to China in 2009, crowdfunding has gained substantial popularity in a relatively short period. Currently, there is still not an identifiable guideline on how to delineate the significance of the crowdfunding platform. The development of crowdfunding in China faces a few unresolved key issues. As researchers exploring this phenomenon in new ways, crowdfunding platforms can be enhanced in a manner that benefits the capital seeker, investors and society as a whole. Originality/value There is a dearth of information on start-up crowdfunding in Asia. With little data available to analyze, so this paper hopes to contribute to knowledge and provide valuable information to researchers and industry representations. Crowdfunding represents a potentially disruptive change in the way that new ventures are funded. This paper represents an initial analysis in the study of new ventures in China. Finally, the authors provide recommendations for entrepreneurs, investors and policymakers as well as researchers and practitioners with suggestions about yet unexplored avenues of research.


Sensor Review ◽  
2018 ◽  
Vol 38 (2) ◽  
pp. 248-258
Author(s):  
Gobi K. ◽  
Kannapiran B. ◽  
Devaraj D. ◽  
Valarmathi K.

Purpose The conventional strain gauge type pressure sensor suffers in static testing of engines due to the contact transduction method. This paper aims to focus on the concept of non-contact transduction-based pressure sensor using eddy current displacement sensing coil (ECDS) to overcome the temperature limitations of the strain gauge type pressure sensor. This paper includes the fabrication of prototypes of the proposed pressure sensor and its performance evaluation by static calibration. The fabricated pressure sensor is proposed to measure pressure in static test environment for a short period in the order of few seconds. The limitations of the fabricated pressure sensor related to temperature problems are highlighted and the suitable design changes are recommended to aid the future design. Design/methodology/approach The design of ECDS-based pressure sensor is aimed to provide non-contact transduction to overcome the limitations of the strain gauge type of pressure sensor. The ECDS is designed and fabricated with two configurations to measure deflection of the diaphragm corresponding to the applied pressure. The fabricated ECDS is calibrated using a standard micro meter to ensure transduction within limits. The fabricated prototypes of pressure sensors are calibrated using dead weight tester, and the calibration results are analyzed to select the best configuration. The proposed pressure sensor is tested at different temperatures, and the test results are analyzed to provide recommendations to overcome the shortcomings. Findings The performance of the different configurations of the pressure sensor using ECDS is evaluated using the calibration data. The analysis of the calibration results indicates that the pressure sensor using ECDS (coil-B) with the diaphragm as target is the best configuration. The accuracy of the fabricated pressure sensor with best configuration is ±2.8 per cent and the full scale (FS) output is 3.8 KHz. The designed non-contact transduction method extends the operating temperature of the pressure sensor up to 150°C with the specified accuracy for the short period. Originality/value Most studies of eddy current sensing coil focus on the displacement and position measurement but not on the pressure measurement. This paper is concerned with the design of the pressure sensor using ECDS to realize the non-contact transduction to overcome the limitations of strain gauge type pressure sensors and evaluation of the fabricated prototypes. It is shown that the accuracy of the proposed pressure sensor is not affected by the high temperature for the short period due to non-contact transduction using ECDS.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Aulia Putri Wahyuningtyas ◽  
Diah Pitaloka Putri ◽  
Nani Maharani ◽  
Ahmad Ni'matullah Al-Baarri

Purpose This paper aims to study the effect of the flavonoid fraction of chayote (Sechium edule (Jacq.) Sw) leaves (FFCL) on uric acid (UA) levels, oxidative stress and inflammatory markers in hyperuricemia rats. Design/methodology/approach In total, 30 Sprague–Dawley rats were divided randomly into 5 groups. A healthy control group was established. Hyperuricemia was induced by the administration of block broth and potassium oxonate for three weeks. FFCL at dosages of 50 and 100 mg/200 g BW/d or allopurinol at a dosage of 1.8 mg/200 g BW/d was given orally for 2 weeks. Statistical analysis was conducted to evaluate differences among groups before and after the intervention. Findings Treatment with two different doses FFCL (50 and 100 mg/200 g BW/d) and one dose of allopurinol (1.8 mg/200 g BW/d) for 2 weeks significantly reduced UA from 8.04 ± 0.23 to 3.88 ± 0.10; 8.03 ± 0.18 to 2.87 ± 0.10; 8.23 ± 0.21 to 2.53 ± 0.19 (p < 0.05), respectively. The oxidative stress marker malondialdehyde levels were reduced (p = 0.001) from 9.68 ± 0.28 to 4.06 ± 0.58; 10.01 ± 0.23 to 2.12 ± 0.09; 9.88 ± 0.21 to 2.02 ± 0.17 (p = 0.001). The inflammatory marker tumor necrosis factor-α (TNF-α) levels were also reduced from 26.43 ± 0.87 to 12.20 ± 0.32; 27.38 ± 0.53 to 9.60 ± 0.53; 27.55 ± 0.68 to 8.83 ± 0.21 with p = 0.001. The 100 mg/200 g BW/d FFCL decreased UA levels, oxidative stress and inflammatory markers more extensively compared to 50 mg/200 g BW/d FFCL. Research limitations/implications This study includes some limitations that may affect the generalizability of its findings. First, the flavonoid levels of FFCL were not measured. Second, other oxidative stress biomarkers (e.g. superoxide dismutase) and inflammatory biomarkers (e.g. IL-6) were not investigated. Finally, the experiments were conducted on the model animals over a relatively short period of time. Further research is needed to evaluate the effect in humans at chronic use. Practical implications Chayote (Sechium edule (Jacq.) Sw) leaves are rich in flavonoids, especially apigenin and luteolin, which can improve oxidative stress and inflammation conditions caused by hyperuricemia. Social implications Hyperuricemia is a risk factor for non-communicable diseases, mostly caused by oxidative stress and inflammation in the body due to high levels of UA, one of the treatment strategies is through diet modification. Originality/value The results of this investigation imply that the administration of the flavonoid fraction of chayote leaves has significant effects on UA and oxidative stress and inflammatory markers. Further research is necessary to confirm the results.


2019 ◽  
Vol 19 (3) ◽  
pp. 186-200
Author(s):  
Deborah B. Kim ◽  
Edward D. White ◽  
Jonathan D. Ritschel ◽  
Chad A. Millette

Purpose Within earned value management, the cost performance index (CPI) and the critical ratio (CR) are used to generate the estimates at completion (EACs). According to the research in the 1990s, estimating the final contract’s cost at completion (CAC) using EACCR is a quicker predictor of the actual final cost versus using EACCPI. This paper aims to investigate whether this trend stills holds for modern department of defense contracts. Design/methodology/approach Accessing the Cost Assessment Data Enterprise (CADE) database, 451 contracts consisting of 863 contract line item numbers (CLINs) were initially retrieved and analyzed in three stages. The first replicated the work conducted in 1990s. The second stage entailed calculating 95 per cent confidence intervals and hypothesis tests regarding percentage accuracy of EACs for a contract’s final CAC. Lastly, regression analysis was conducted to characterize major, moderate and minor influencers on EAC reliability. Findings For modern contracts, EACCR aligns more with EACCPI and no longer demonstrates early accuracy of a contract’s final CAC. Contract percentage completion strongly reduced the per cent error of estimating CAC, while cost-plus-fixed-fee contracts and those with no work breakdown structure greater than Level 2 negatively affected accuracy. Social implications To militate against optimism of early assessment of a contract's true cost. Originality/value This paper provides empirical evidence that EACCR behaves more like EACCPI with respect to modern contracts, suggesting that today’s contracts have relatively high SPI. Therefore, caution is warranted for program managers when estimating the CAC from contract initiation up to and slightly beyond the mid-point of completion.


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