Flight Research Articles

Regal Fritillary (Speyeria idalia) Sex Ratio in Tallgrass Prairie: Effects of Survey Timing and Management Regime

The regal fritillary, Speyeria idalia (Drury), was once a common inhabitant of North American grassland communities. Regal fritillary populations are commonly reported to have a male biased adult sex ratio (ASR) throughout their range. We assessed the observed ASR of regal fritillary throughout an annual flight period, investigated how the overall density of both sexes changed, and tested effects of prescribed fire, grazing and haying management treatments on male and female density. We found that regal fritillary exhibited an observed 2:1 male biased ASR across the entire emergence period. Our analysis also revealed that male density peaked earlier than female density in the flight period. Point estimates of density indicated sites that received prescribed burning at the moderate fire-return interval supported ≥1.3 times greater density of males and ≥5.6 times greater density of females versus sites burned with short and long fire-return intervals. Additionally, this effect was enhanced when combined with grazing which showed males were ≥1.9 times and females had ≥1.2 times greater point estimates of density in sites that were grazed and burned at a moderate fire-return interval versus other sites. The relatively stable status of regal fritillary within our study region suggests that a 2:1 male to female ASR may be considered the model composition of populations throughout their range. Likewise, the dynamic nature of the ASR throughout the flight period highlights the importance of conducting surveys across the flight period. Finally, these results corroborate an increasing number of research results that reveal common prairie management practices, such as prescribed fire can be applied within sites that contain regal fritillary and continue to support stable populations.

The Impact of Corporate Recovery Efforts on Corporate - Customer Relationship

Purpose: There are many problems in service quality management for the airline service industry due to their irresistible nature. In the case of airline service, the main cause of service failure is flight cancellation. Cancellation of flights is often caused by natural disasters. Nonetheless, customers expect service recovery from airlines. This study was conducted to investigate how airline companies should respond to service failures in the event of a irresistible airline service failure. Research design, data, and methodology: This study conducted an online survey to customers (900) who have experienced flight cancellation or delay in specific situation like closure of runway, etc. caused by natural disaster. In the first screening process, those who have experienced such failures were about 30% among all respondents. Among 900 respondents who answered that they had experienced such airline failure, 211 answered that those failures were irresistible and airlines could not control the situations. Results: This study conducted an online survey to customers who have experienced flight cancellation or delay in specific situation like closure of runway, etc. caused by natural disaster. In the first screening process, those who have experienced such failures were about 30% among all respondents. Among 900 respondents who answered that they had experienced such airline failure, 211 answered that those failures were irresistible and airlines could not control the situations. First of all, among the kinds of perceived justice, distributional justice and procedural justice were found to have positive effects on recovery satisfaction. Plus, recovery satisfaction was found to have positive effect on customer Citizenship behavior and long-term orientation. Conclusions: The results of the study suggest that service recovery justice impacts on recovery satisfaction significantly. Also the higher the service recovery justice, the higher recovery satisfaction, then it increases customers'' forgiveness, Customer Citizenship Behavior, and long-term orientation.

Strategies of Resilience: Cooperation in Irish Family Farming

Drawing from both historical ethnographic sociology and more recently collected narrative data, we trace changing resilience strategies employed by Irish family farms. We focus specifically on collective action within farm families and communities, a pathway to resilience that has traditionally depended on patriarchal relations and an accession of individual interests to the survival of the family farm. We find that new conditions for resilience have emerged, disrupting relationships on which historical forms of collective action depended. Threatened with the flight of women and youth towards off-farm opportunities, resilience strategies have come to accommodate better and respond to the needs of individuals in farm families. However, if the farm is to survive, family members remain collectively challenged with meeting its physical demands. One contemporary resilience strategy employs Joint Farming Ventures (JFVs), which involve formalised collaborative arrangements between husbands and wives, parents and offspring, non-immediate relatives, and farming neighbours. We find women and men at different stages in the lifecourse are employing JFVs to drive and resource renewed resilience strategies. Reconstituted relational arrangements within the farm family allow the farm to draw from an increased range of resources through an enhanced commitment of diverse farm family members. By prioritising the family farm, contemporary resilience strategies are consistent with historical ones but create greater capacity for family farm resilience by boosting reservoirs of social, cultural and economic capital available to the farm. This insight goes some way towards shedding light on the intricate puzzle that is the remarkable resilience of Irish family farms and those continuing to exist worldwide.

Primaveras, Tribunais e Dólares: Uma análise panorâmica das crises políticas na América Latina (1990-2020)

The article analyse three forms of intervention on institutional politics in situations of political crises in contemporary Latin America: the relatively sudden irruption of multitudinous protests with popular, oppositional and citizen identity (‘springs’); the intervention of accountability institutions (‘courts’); and the interference on representation as a result of capital flight risk (‘dollars’). It presents a historical mapping of 37 episodes of political crises in 15 countries in the region between 1990 and 2020, framing them as exceptional circumstances of blockade in usual expediency of the political system. Reviewing those cases and the literature on institutional crises, it develops the meaning of ‘springs’, ‘courts’, and ‘dollars’, discarding the hypothesis that they represent a somehow transitory stage in democratic consolidation. Instead, two arguments unfold: first, that the ‘unarmed’ character of such interventions is a discontinuity in Latin American history, in contrast to the predominantly armed forms of political disruption; second, beyond critical junctures, these unarmed interventions generate effects even when they do not occur, shaping practices, expectations and boundaries of liberal democracy in the region.

The modified Ziegler-Nichols method for obtaining the optimum PID gain coefficients under quadcopter flight system

The modified Ziegler-Nichols method for obtaining the optimum PID gain coefficients under quadcopter flight system

Association between type I interferon receptor 1 single nucleotide polymorphisms and susceptibility to tuberculosis

Objective To investigate the relationship between single nucleotide polymorphism (SNP) of type I interferon receptor 1 (IFNAR1) and susceptibility to tuberculosis in the Han population in southern China. Methods A case-control study was used, with 1 533 patients with active tuberculosis (including 1 432 tuberculosis and 101 extrapulmonary tuberculosis) as the case group, and 1 445 healthy people as the control group. Interferon (IFN) gene rs72552343, rs2834191, rs1012334, rs17875752, rs2843710, rs1041868 genotypes were detected by MassARRAY time-of flight mass spectrometry. The differences in the frequency of SNP alleles between the two groups were analyzed, and the differences in the frequency of rs72552343 TCC / Del locus in patients with pulmonary tuberculosis and extrapulgative tuberculosis were further compared. Results MassARRAY time-of-flight mass spectrometry can effectively detect the genotypes of six SNP loci. Among the 6 SNP loci, it was found that only the rs72552343 TCC/Del locus allele frequency was significantly different between the active tuberculosis group and the control group, and the rs72552343 TCC/Del locus TCC allele frequency was significantly increased ( OR =0.46; 95% CI =0.31 -0.70; P =0.000 2), the frequency of the other five SNP alleles was not significantly different between the two groups. In addition, the frequency of TCC alleles at rs72552343 TCC / Del loci in patients with extrapulmonary tuberculosis was not significantly different from that in patients with tuberculosis ( OR =0.88; 95% CI =0.20-3.74; P =0.86). Conclusion The IFN gene rs72552343 TCC / Del site SNP is related to susceptibility to tuberculosis. The TCC allele is a susceptibility gene for tuberculosis, but individuals carrying the TCC allele have the same risk of active pulmonary tuberculosis as those with extrapulmonary tuberculosis. 摘要：目的 探究Ⅰ型干扰素受体 1 (typeⅠinterferon receptor 1, IFNAR1) 单核苷酸多态性 (single nucleotide poly⁃ morphism, SNP) 与结核病易感性的关系。 方法 应用病例-对照研究方法, 以深圳市第三人民医院 1 533 例活动性结核 病患者 (包括 1 432 例肺结核、101 例肺外结核) 作为病例组, 1 445 例健康人群作为对照组。运用 MassARRAY 飞行时间 质 谱 技 术 , 通 过 检 测 Ⅰ 型 干 扰 素 (interferon, IFN) 基 因 rs72552343、rs2834191、rs1012334、rs17875752、rs2843710、rs1041868 位点基因型, 分析两组间 SNP 等位基因频率差异, 同时进一步比较肺结核与肺外结核病患者 rs72552343 TCC/Del 位点等位基因频率差异。 结果 用 MassARRAY 飞行时间质谱技术可以有效地检测 6 个 SNP 位点基因型。在 6 个 SNP 位点中, 发现仅 rs72552343 TCC/Del 位点等位基因频率在活动性结核组和对照组中差异有统计学意义 ( P 0.05)。另外, 发现肺外结核病患者 rs72552343 TCC/Del 位点 TCC 等位基因的频率与肺结核病患者差异无统计学意 义 ( OR =0.88; 95% CI =0.20~3.74; P =0.86)。 结论 IFN 基因 rs72552343 TCC/Del 位点 SNP 与结核易感性相关, 其 TCC 等位基因为结核易感基因, 但携带 TCC 等位基因的个体患活 动性肺结核与肺外结核的风险一致。

A Study of the Construction of Comprehensive Flight Testing Infrastructure to Increase Aviation Safety

A Study of the Construction of Comprehensive Flight Testing Infrastructure to Increase Aviation Safety

A Study for Optimization of Armed Flight Test Ammunition Requirement for the Development of Attack Helicopter

A Study for Optimization of Armed Flight Test Ammunition Requirement for the Development of Attack Helicopter

Measuring method and experiment on spray drift of chemicals applied by UAV sprayer based on an artificial orchard test bench

In recent years, low-altitude and low-volume plant protection operations using unmanned aerial vehicle (UAV) sprayer developed rapidly in China with the advantages of high efficiency, labour saving, high safety, high terrain adaptability, high flexibility, water and chemicals saving, and high intelligence. With the UAV application technology in field crops is becoming more and more mature, aerial spraying operations in orchards are promising and in the ascendant, but a high risk of UAV spray drift is appearing due to high working height and fine droplets sprayed in slope orchards, highlighting the necessity of the study on the spray drift characteristics of UAV chemicals application for fruit trees. Therefore, based on previous research, a novel type of measuring method of spray drift for UAV chemicals application in orchard was proposed in this study and an artificial orchard test stand (vineyard) and 3 airborne drift frame collectors were designed and built, and a set of field drift test bench was firstly used to collect aerial spray drift droplets at different downwind distances, together with ground drift collectors and canopy deposition collectors. An airborne drift index (ADX) of UAV’s spray was initially applied for quantitative analysis to compare spray drift characteristics of different models of unmanned aircrafts and variable operation parameters. Fluorescence tracer Pyranine water solution was prepared at the concentration of 0.1% as the spray liquid. Four typical types of plant protection UAV (a single-rotor oil-powered helicopter, a 6-rotor motor drone and two models of 8-rotor motor drones) equipped with conventional hollow cone nozzle ‘TR 80-0067’ and air-induction anti-drift nozzle ‘IDK 120-015’were tested in the artificial vineyard, and results of canopy deposition distribution, ground sediment drift, near-ground drift, and airborne drift were obtained and analysed, and different sampling collectors for spray drift were evaluated and compared. The results showed that: Under the environmental conditions that the nominal crosswind speed was 2.4-3.6 m/s, the temperature was 29.8-34.3 ℃ and relative humidity was 10.7%-30.6%, at the flight height of 1.5 m (3.5 m from the ground) and the speed of 2.0 m/s the air-induction nozzle IDK can significantly reduce the level of downwind spray drift of UAV, optimize the uniformity of deposition distribution and increase the effective utilization rate of chemicals; There was no significant difference in the drift characteristics of the 4 types of unmanned aircraft, and the vortex generated by the combination of the rotor’s downwash airflow and the external wind was an important factor on spray drift; Buffer zone of UAV aerial spraying operation in vineyards should be set at at least 15 m; The lower the canopy deposition rate (P 0), the larger the average average drift rate (AADR) and 90% cumulative drift distancex90% of the field drift test bench (P 0), the greater the ADX value (P 0) all indicated the higher spray drift risk, respectively; Both these sampling collectors and their evaluation index could assess the downwind drift characteristics effectively; the relationship between the UAV spray drift rate βdep% and the downwind distance x was described by the exponential function. The results of this study are expected to provide references and data supports for the R&D of UAV dedicated for orchard spraying, the formulation of standards on spray drift field measuring method for UAV orchard operations and the selection of aerial application working parameters in orchards.

A multi-dimensional comprehensive evaluation model of mental workload for complex flight missions

A multi-dimensional comprehensive evaluation model of mental workload for complex flight missions

Recognition of fighter maneuver in automatic flight training evaluation

Recognition of fighter maneuver in automatic flight training evaluation

The Damage Caused by Aircraft Flight and the Issues Related to Civil Law- The Study on the Supreme Court Decision 2013Da71098

The Damage Caused by Aircraft Flight and the Issues Related to Civil Law- The Study on the Supreme Court Decision 2013Da71098

The Effect of Positive Psychological Capital and Leader-Member Exchange on Job Stress, Organizational Commitment, and Knowledge Sharing - Focusing on Flight Attendants -

The Effect of Positive Psychological Capital and Leader-Member Exchange on Job Stress, Organizational Commitment, and Knowledge Sharing - Focusing on Flight Attendants -

Effects of Perceived Flight Attendants' Authentic Leadership on Job Meaningfulness and Job Engagement: The Mediating Effect of Job Meaningfulness

항공사의 경쟁우위를 위해서는 우수한 인적자원을 유지하고 이를 통해 조직 효율성을 확보하는 전략에 초점을 맞추어야 한다. 따라서 본 연구는 항공사 객실승무원을 연구대상으로 선정하여 첫째, 항공사 객실승무원이 지각하는 진정성 리더십과 직무 의미성의 관계를 밝히고자 하였고, 둘째, 항공사 객실승무원이 지각하는 진정성 리더십과 직무열의의 관계를 검증하고자 하였으며, 셋째, 직무 의미성과 직무열의의 관계를 검증하고자 하였으며, 마지막으로 항공사 객실승무원이 지각하는 진정성 리더십과 직무열의의 관계에 미치는 직무 의미성의 매개효과를 검증하고자 하였다. 자료 수집을 위한 설문조사는 국내대형항공사 2곳의 객실승무원을 대상으로 객실승무원의 근무형태를 고려하여 2020년 1월 8일부터 1월 31일까지 실시되었다. 설문지는 총 280부를 배포하여 257부가 회수되었으며 그 중 응답이 불성실한 23부를 제외한 총 234부가 분석에 사용되었다. 실증분석 결과는 다음과 같다. 첫째, 항공사 객실승무원이 지각하는 진정성 리더십은 직무 의미성에 유의한 정(+)의 영향을 미치는 것으로 나타났다. 둘째, 항공사 객실승무원이 지각하는 진정성 리더십은 직무열의에 유의한 정(+)의 영향을 미치는 것으로 나타났다. 셋째, 직무 의미성은 직무열의에 유의한 정(+)의 영향을 미치는 것으로 나타났다. 마지막으로 항공사 객실승무원이 지각하는 진정성 리더십과 직무열의의 관계에서 직무 의미성은 유의한 부분매개효과를 나타내는 것으로 검증되었다. 항공 서비스 산업의 규모가 커지고 무한 경쟁 시대에 들어서서 인적자원의 중요성은 점점 더 커지고 있다. 따라서 본 연구는 항공사 객실승무원의 긍정적인 태도를 장려하기 위해 객실승무원에 의해 지각된 진정성 리더십의 영향을 검증하였다는 데에서 의미가 있다고 하겠다

Aerodynamic design optimization of an aircraft wing for drag reduction using computational fluid dynamics approach

The aircraft industry supports aviation by building aircraft and manufacturing aircraft parts for their maintenance. Fuel economization is one of the biggest concerns in the aircraft industry. The reduction in specific fuel consumption of aircraft can be achieved by a variety of means, simplest and more effective is the one to impose minor modifications in the aircraft main wing or the parts which are exposed to the air flow. This method can lead to a reduction in aerodynamic resistance offered by the air and have a smoother flight. The main objective of this study is to propose geometric design modifications on an existing aircraft wing which acts as a vortex generator and it can reduce the drag and increase lift to drag ratio, leading to lower fuel consumption. The NACA 2412 aircraft wing is modified and designed. Rigorous flow analysis is carried out using computational fluid dynamics based software Ansys Fluent. Results show that saw tooth modification to the main wing shows the best aerodynamic efficiency as compared to other modifications.

La structure des taux revisitée pour période de crise : entre contagion, flight to quality et quantitative easing

Cet article cherche à évaluer le rôle spécifique des risques de volatilité et de covolatilité dans la formation des taux d’intérêt à long terme de la zone euro sur les périodes de crise et post-crise, marquées par un rôle actif de la BCE. On propose pour cela un modèle de choix de portefeuille obligataire à deux pays qui permet de généraliser les résultats de la théorie traditionnelle de la structure par terme des taux d’intérêt. Les taux longs d’équilibre dépendent crucialement des covariances anticipées par les investisseurs sur les rendements obligataires. Des covariances anticipées positives amplifient les phénomènes de contagion par les fondamentaux en cas de dégradation des finances publiques, tandis que des covariances négatives amplifient les phénomènes de flight to quality . Le modèle est estimé économétriquement dans un cadre GARCH bivarié sur 21 paires de marchés obligataires souverains observés sur la période janvier 2006-septembre 2016. Cette évaluation empirique fait ressortir trois résultats importants. 1) La baisse des taux longs allemand et français très tôt dans la crise, à partir de mars 2011, a trouvé un support important dans la baisse des covariances anticipées vis-à-vis des pays périphériques, qui a véritablement amplifié le processus de flight to quality . 2) La logique des choix de portefeuilles optimaux, révélée par la sensibilité des taux longs aux risques de volatilité, semble disparaître pendant la crise pour réapparaître ensuite, à partir de la mise en place de l’OMT. 3) Un test à la Forbes et Rigobon [2002] sur les composantes non fondamentales des taux longs ne permet pas de conclure que le QE de la BCE, à partir de mars 2015, a véritablement entraîné une re-corrélation des marchés obligataires de la zone euro. Ce paradoxe s’explique par le fait que ces corrélations étaient déjà en moyenne élevées à la suite de l’OMT.

The Homecoming Flight

The Homecoming Flight

Aircraft Interior Requirements for a Good Sleep

Sleeping in long haul flights is difficult. There is noise, an upright sitting position and neighbours and crew disturb the sleep. However, there is not much information available for designers on the most important factors next to the seat that could improve the sleep quality. In this paper a co-creation session and a survey among 109 participants has been performed to study factors influencing sleep in a long-haul flight. This study shows that not only the seat is important for a good sleep, but factors like privacy, hygiene and neighbours play a role as well. The more frequent travellers experience more comfort during sleep. So, probably a good preparation is important as well.

The homing flight method to assess the effect of sublethal doses of plant protection products on the honey bee in field conditions: results of the ring tests and proposal of a new OECD TG

The homing flight method to assess the effect of sublethal doses of plant protection products on the honey bee in field conditions: results of the ring tests and proposal of a new OECD TG

COVID-19: fight or flight.

COVID-19: fight or flight.