scholarly journals A Holistic Approach for Optimal Pre-Planning of Multi-Path Standardized Taxiing Routes

Aerospace ◽  
2021 ◽  
Vol 8 (9) ◽  
pp. 241
Author(s):  
Lei Yang ◽  
Simin Wang ◽  
Fengjie Liang ◽  
Zheng Zhao
Keyword(s):  
Holistic Approach ◽  
Ground Movement ◽  
Time Varying ◽  
Human In The Loop ◽  
Congestion Cost ◽  
Routing Optimization ◽  
Substantial Investment ◽  
Performance Results ◽  
The Impact ◽  
Positive Effect

Standardized Taxiing Routes (STRs) are defined as published taxiing-in and taxiing-out routes for aircraft between gates and runways, aiming at improving ground movement safety at busy or complex airports. Most of the STRs specify only one path between each O–D (Origin–Destination) pair, which compromises the flexibility of route choice in time-varying traffic scenarios. In this paper, we present a holistic approach of planning and validating Multi-Path Standardized Taxiing Routes (MPSTRs) based on System-Optimal Traffic Assignment (SOTA), by firstly defining the flow-based congestion cost of runway, taxiway, and sectorized apron operation at a macroscopic level. A human-in-the-loop experiment comprised of six operation scenarios follows to investigate the impact of the pre-planned MPSTRs on human controllers’ performance. Results confirm the positive effect of the MPSTRs on taxiing performance without increasing the controllers’ workload, which also implies that the MPSTRs would be a promising approach for balancing safety and efficiency for the STRs-based taxiing operation and dynamic routing optimization without substantial investment.

Environmental Effects of Trade Liberalization–Evidence from China’s Pilot Free Trade Zone

2021 ◽  
pp. 2150013
Author(s):  
Lianghu Wang ◽  
Zhao Wang ◽  
Yatian Ma
Keyword(s):  
Environmental Pollution ◽  
Free Trade ◽  
Environmental Effects ◽  
Natural Experiment ◽  
Free Trade Zone ◽  
Time Varying ◽  
Pollution Problem ◽  
Environmental Pollution Problem ◽  
The Impact ◽  
Positive Effect

Free trade zone (FTZ) in China has been demonstrating remarkable achievements since its establishment, yet its effects on the environment in the zones cannot be ignored. However, there is still a lack of research on the impact of the quasi-natural experiment in the China pilot FTZ on China’s environment. Based on this, this paper uses panel data from 196 cities in China from 2010 to 2017 and uses the propensity score matching and difference in difference (PSM-DID) model to empirically test the environmental effects of the establishment of the FTZ. The result shows that there is an obvious causal relationship between the establishment of the FTZ and environmental quality. The establishment of the FTZ has exacerbated the environmental pollution problem in the pilot zone. Through a series of robustness tests, it is concluded that the estimated results of the benchmark model are robust. However, after a further study on whether the effect of the FTZ on environment is time varying, it was found that the effects of the FTZ on the environmental pollution in the test zones gradually weakened over time, which means that with the gradual maturity of China’s free trade pilot zone, the positive effect on environmental improvement will gradually highlight.

scholarly journals Institutional Investor Shareholdings and Corporate Social Responsibility – Evidence from Tourism Related Industries in China

2021 ◽  
Vol 251 ◽  
pp. 03016
Author(s):  
Lei Zheng ◽  
Xuemeng Guo ◽  
Libin Zhao ◽  
Yuting Feng
Keyword(s):  
Corporate Social Responsibility ◽  
Social Responsibility ◽  
Institutional Investor ◽  
Listed Companies ◽  
Public Companies ◽  
Using Data ◽  
Corporate Social ◽  
Performance Results ◽  
The Impact ◽  
Positive Effect

Using data from Chinese A-share listed companies in tourism related industries from 2009 to 2018, this paper examines the influence of institutional investor shareholdings on corporate social responsibility (CSR) performance. Results show that: First, institutional investor shareholdings can significantly improve CSR performance of tourism related public companies in China. After implementing robustness test, this positive relationship remains solid. Second, the positive effect of institutional investor shareholdings is significantly unbalanced regarding different CSR dimensions, with the most salient influence in promoting companies’ social welfare contributions. And third, the impact of institutional investor shareholdings can be strengthened when listed companies are ultimately controlled by the state.

Impact of Digitalization on Service Work in Knowledge-Intensive Business Services: An Empirical Study in Tax Consultancies

2019 ◽  
Vol 3 (4) ◽  
pp. 209-222
Author(s):  
Philipp K. Görs ◽  
Henning Hummert ◽  
Anne Traum ◽  
Friedemann W. Nerdinger
Keyword(s):  
Work Engagement ◽  
Service Work ◽  
Psychological Consequences ◽  
Business Services ◽  
Knowledge Intensive Business Services ◽  
Positive Effects ◽  
Knowledge Intensive ◽  
The Impact ◽  
Positive Effect ◽  
Special Case

Digitalization is a megatrend, but there is relatively little knowledge about its consequences for service work in general and specifically in knowledge-intensive business services (KIBS). We studied the impact of digitalization on psychological consequences for employees in tax consultancies as a special case of KIBS. We compare two tax consulting jobs with very different job demands, those of tax consultants (TCs) and assistant tax consultants (ATCs). The results show that the extent of digitalization at the workplace level for ATCs correlates significantly positively with their job satisfaction. For TCs, the same variable correlates positively with their work engagement. These positive effects of digitalization are mediated in the case of ATCs by the impact on important job characteristics. In the case of TCs, which already have very good working conditions, the impact is mediated by the positive effect on self-efficacy. Theoretical and practical consequences of these results are discussed.

Comparative study of the impact of two mechanical perforation densities on the behavior of a sandy soil

2012 ◽  
Vol 8 (1) ◽  
pp. 37-48
Author(s):  
S. Chehaibi ◽  
K. Abrougui ◽  
F. Haouala
Keyword(s):  
Soil Water ◽  
Sandy Soil ◽  
Water Infiltration ◽  
Cone Penetration ◽  
Initial State ◽  
Soil Water Infiltration ◽  
Good Improvement ◽  
The Impact ◽  
Positive Effect ◽  
Resistance To Penetration

The effects of mechanical perforation densities by extracting soil cores through an aerator Vertidrain with a working width of 1.6 m and equipped with hollow tines spaced of 65 mm, were studied on a sandy soil of a grassy sward in the Golf Course El Kantaoui in Sousse (Tunisia). The mechanical aeration was performed at two densities: 250 and 350 holes/m2. The cone penetration resistance and soil water infiltration were measured. These parameters were performed at initial state before aeration (E0) and then on the 10th, 20th and 30th day after aeration. These results showed that perforation density of 350 holes/m2 had a positive effect on the soil by reducing its cone resistance to penetration compared to the initial state (Rp = 14.8 daN/cm2). At 5 cm depth the decrease in resistance to penetration was 34% and 43% on the 10th and 20th day after aeration, respectively. However, on the 30th day after aeration the soil resistance to penetration tended to grow and its value compared to the initial state decreased only by 21 and 26%, respectively, at 5 and 15 cm of depth only by 10% and 9% with 250 holes/m2 density. The soil water infiltration made a good improvement after aeration compared to the initial state. This parameter increased from 4.8 cm/h to 8.3, 10.9 and 13.1 cm/h with 250 holes/m2 density and to 10, 12.9 and 14.8 cm/h with 350 holes/m2 density on the 10th, 20th and 30th day following the aeration.

THEORETICAL STUDY OF THE EFFECT OF GEOMETRICAL PARAMETERS AND LOCATION OF ROTOR IMPACT ELEMENTS OF AN IMPACT-CENTRIFUGAL GRINDER ON SPEED AND ANGLES OF CRUSHED PARTICLES FLIGHT

2020 ◽  
Keyword(s):  
Granulometric Composition ◽  
Theoretical Study ◽  
Process Efficiency ◽  
Geometrical Parameters ◽  
Grinding Process ◽  
Main Work ◽  
Impact Element ◽  
The Impact ◽  
Positive Effect ◽  
Efficiency Indicators

One of efficiency indicators of grain grinders is grain granulometric composition. The basis of mixed fodder is crushed grain, the particles of which must have a leveled granulometric composition for subsequent mixing and obtaining a high-quality feed mixture. In agricultural production, hammer crushers are widely used, in which the destruction of grain occurs due to the impact of a hinged hammer. The main disadvantage of these crushers is that not the entire surface of the hammers is involved in grinding, thus reduces grinding process efficiency. A slightly different principle of material destruction is laid down in the basis of the proposed design of the shock-centrifugal grinder. Main work is performed by flat impact elements located on the rotor, which serve to accelerate crushed particles with subsequent impact of them on the bump elements. An important step in the design of new constructions of shock-centrifugal grinders is to determine size and location of the impact elements on the rotor, without which the grinding process is not possible. In the calculation method presented, the dependencies for determining the velocities and angles of a single particle flight from the surface of a flat impact element for its specified dimensions are proposed. Two variants of an impact element location on the rotor are considered and analyzed: radial and at an angle in the direction of rotor rotation. As a result of research carried out, it is noted that in the case of inclined position of an impact element on the rotor an increase in flight speed and flight angles change in crushed particles, which gives the opportunity to have a positive effect on grinding process.

Investigating the Impact of Human in-the-Loop Digital Twin in an Industrial Maintenance Context

2020 ◽  
Author(s):  
Ali Al-Yacoubb ◽  
Will Eaton ◽  
Melanie Zimmer ◽  
Achim Buerkle ◽  
Dedy Ariansyaha ◽  
...  
Keyword(s):  
Digital Twin ◽  
Human In The Loop ◽  
Industrial Maintenance ◽  
The Impact

The Impact of Coping Strategies on Situational Coping in Daily Life: An Ecological Momentary Assessment Study with the mHealth application TrackYourStress (Preprint)

2020 ◽  
Author(s):  
Teresa O'Rourke ◽  
Carsten Vogel ◽  
Dennis John ◽  
Rüdiger Pryss ◽  
Johannes Schobel ◽  
...  
Keyword(s):  
Social Support ◽  
Coping Strategies ◽  
Daily Life ◽  
Stress Coping ◽  
Positive Thinking ◽  
Active Stress ◽  
Situational Coping ◽  
Ecological Momentary ◽  
The Impact ◽  
Positive Effect

BACKGROUND It is necessary to cope with situations in daily life to prevent stress-related health consequences. However, coping strategies might differ in their impact on dealing with stressful situations in daily life. Moreover, the effect of coping strategies on situational coping might differ between women and men. OBJECTIVE The aim of this study was to investigate the impact of coping strategies on situational coping in everyday life situations and to investigate gender differences. METHODS An ecological momentary assessment study with the mobile health app TrackYourStress (TYS) was conducted with 113 participants. Coping strategies were measured at baseline with the coping scales Positive Thinking, Active Stress Coping, Social Support, Support in Faith, and Alcohol and Cigarette Consumption of the Stress and Coping Inventory (SCI). Situational coping was assessed by the question “How well can you cope with your momentary stress-level” (slider 0-100) in daily life over four weeks. Multilevel models were conducted to test the effects of the coping strategies on situational coping. Additionally, gender differences were evaluated. RESULTS Positive Thinking (P=.03) and Active Stress Coping (P=.04) had significant positive impacts on situational coping in the total sample. For women, only Social Support had a significant positive effect on situational coping (P=.046). For men, only Active Stress Coping had a significant positive effect on situational coping (P=.001). Women had higher scores on the SCI scale Social Support than men (P=.007). CONCLUSIONS These results suggest that different coping strategies could be more effective in daily life for women than for men, which should be considered in the development of interventions aimed at reducing stress consequences through coping. Interventions taking gender into consideration might lead to better coping-outcomes than generalized interventions.

THE IMPACT OF WORLD WAR II ON COST ACCOUNTING AT THE SPERRY CORPORATION

2003 ◽  
Vol 30 (2) ◽  
pp. 67-104 ◽  
Author(s):  
Richard K. Fleischman ◽  
R. Penny Marquette
Keyword(s):  
World War Ii ◽  
Performance Management ◽  
Scientific Management ◽  
World War ◽  
Military Contractors ◽  
Management Techniques ◽  
Cost Awareness ◽  
The Impact ◽  
Positive Effect ◽  
The U.S

The impact of World War II on cost accountancy in the U.S. may be viewed as a double-edged sword. Its most positive effect was engendering greater cost awareness, particularly among companies that served as military contractors and, thus, had to make full representation to contracting agencies for reimbursement. On the negative side, the dislocations of war, especially shortages in the factors of production and capacity constraints, meant that such “scientific management” techniques as existed (standard costing, time-study, specific detailing of task routines) fell by the wayside. This paper utilizes the archive of the Sperry Corporation, a leading governmental contractor, to chart the firm's accounting during World War II. It is concluded that any techniques that had developed from Taylorite principles were suspended, while methods similar to contemporary performance management, such as subcontracting, emphasis on the design phase of products, and substantial expenditure on research and development, flourished.

scholarly journals Modulation of Gut Microbiota and Oxidative Status by β-Carotene in Late Pregnant Sows

2020 ◽  
Vol 7 ◽  
Author(s):  
Xupeng Yuan ◽  
Jiahao Yan ◽  
Ruizhi Hu ◽  
Yanli Li ◽  
Ying Wang ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Dietary Supplementation ◽  
Basal Diet ◽  
Fecal Microbiota ◽  
Control Group ◽  
Metabolic Activities ◽  
The Impact ◽  
Positive Effect ◽  
Β Carotene

Recent evidences suggest that gut microbiota plays an important role in regulating physiological and metabolic activities of pregnant sows, and β-carotene has a potentially positive effect on reproduction, but the impact of β-carotene on gut microbiota in pregnant sows remains unknown. This study aimed to explore the effect and mechanisms of β-carotene on the reproductive performance of sows from the aspect of gut microbiota. A total of 48 hybrid pregnant sows (Landrace × Yorkshire) with similar parity were randomly allocated into three groups (n = 16) and fed with a basal diet or a diet containing 30 or 90 mg/kg of β-carotene from day 90 of gestation until parturition. Dietary supplementation of 30 or 90 mg/kg β-carotene increased the number of live birth to 11.82 ± 1.54 and 12.29 ± 2.09, respectively, while the control group was 11.00 ± 1.41 (P = 0.201). Moreover, β-carotene increased significantly the serum nitric oxide (NO) level and glutathione peroxidase (GSH-Px) activity (P < 0.05). Characterization of fecal microbiota revealed that 90 mg/kg β-carotene increased the diversity of the gut flora (P < 0.05). In particular, β-carotene decreased the relative abundance of Firmicutes including Lachnospiraceae AC2044 group, Lachnospiraceae NK4B4 group and Ruminococcaceae UCG-008, but enriched Proteobacteria including Bilophila and Sutterella, and Actinobacteria including Corynebacterium and Corynebacterium 1 which are related to NO synthesis. These data demonstrated that dietary supplementation of β-carotene may increase antioxidant enzyme activity and NO, an important vasodilator to promote the neonatal blood circulation, through regulating gut microbiota in sows.

scholarly journals Impacts of COVID-19 on Animals in Zoos: A Longitudinal Multi-Species Analysis

2021 ◽  
Vol 2 (2) ◽  
pp. 130-145
Author(s):  
Ellen Williams ◽  
Anne Carter ◽  
Jessica Rendle ◽  
Samantha J. Ward
Keyword(s):  
Holistic Approach ◽  
Physiological Measures ◽  
Environmental Interactions ◽  
Species Analysis ◽  
Zoo Animals ◽  
Animal Interaction ◽  
Chinese Goral ◽  
Grevy’S Zebra ◽  
The Impact ◽  
Swamp Wallaby

Prolonged and repetitive COVID-19 facility closures have led to an abrupt cessation of visitors within UK and Irish zoos for variable periods since March 2020. This study sought to increase understanding of the impact of closures and reopenings on animal behaviour, thereby broadening understanding of whether zoo animals habituate to visitors. Data were collected from June to August 2020 at two UK facilities on eight species (n = 1 Chinese goral, n = 2 Grevy’s zebra, n = 11 swamp wallaby, n = 2 Rothschild’s giraffe, n = 2 nyala, n = 4 Chapman’s zebra, n = 2 snow leopard and n = 3 Amur leopard). Behaviour change and enclosure use was variable across species but most changes were non-significant. Grevy’s zebra engaged in more comfort behaviour during closure periods than post-closure (p < 0.05). Chinese goral engaged in more environmental interactions during closure periods (p < 0.05). Grevy’s zebra spent longer than would be expected by chance closest to public viewing areas during closure periods (p < 0.008). These results suggest variable impacts of covid-19 closures and reopenings, mirroring human-animal interaction literature. We highlight the potential for some species to take longer to re-habituate to the presence of zoo visitors. As facility closures/reopenings are ongoing, we advocate a longitudinal monitoring approach. Furthermore, we recommend incorporation of physical and physiological measures of welfare where possible, alongside behavioural responses, to enable a holistic approach to answering fundamental questions on whether zoo animals habituate to visitors.

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