Asian Sector Research Articles

A study of spatio-temporal variability of equatorial electrojet using long-term ground-observations

It is widely accepted that a quiet time equatorial electrojet (EEJ) varies daily, monthly, seasonally, and longitudinally; however, detailed characterization of these variations has not yet been done using multiple ground based stations. Therefore, the purpose of this article is to give a reasonably comprehensive comparison of day-to-day, monthly, seasonal, and longitudinal variabilities of the EEJ and its reversal counter electrojet (CEJ) occurrence during the period from 2011 to 2013. The analysis is based on a 1-minute ground-based magnetic data recorded at eight dip equatorial stations. The results obtained in this study indicate that the mean day-side EEJ is strongest around equinoxes months in the Peruvian, Southeast Asia and Philippine regions throughout the years investigated. On the other hand, stations in the African and Indian regions show medium peaks in the equinoxes months of the years 2011–2012. The EEJ strength in the Pacific sector is weakest throughout the years. The observed seasonal behavior of the peak EEJ during equinox is observed at 10:30–12:00 LT for Peruvian, Southeast Asian, and Philippine regions, but in the West African and Indian sectors, the medium EEJ peaks were observed about 1 h earlier. We also found that, on average, morning CEJ events occur more frequently than in the evening CEJ at TTB followed by AAE and HUA. The largest morning CEJ fluctuations were observed for the TTB during the whole months of the years considered in this study except the December months of 2012. During the December solstice months of 2011, the EEJ current in TTB is maximum while the medium peak has been shown in 2012 and 2013. Overall the observed average EEJ strength is maximum during equinoxes and minimum in solstices months as well as seasons. Our results also show that the magnitude of EEJ gradually increases in the Peruvian and Southeast Asian sectors while the rate of MCEJ occurrence increases at Brazilian and African regions from the years 2011 to 2013. It is also observed that the magnitude of EEJ is highering during the years of the increasing solar cycle.

The Value Of Buildings And Structures For Permafrost Damage Prediction: The Case Of Eastern Russian Arctic

The relevance of the study lay in the need to obtain reliable information on the possible economic consequences of changing geocryological conditions in the Russian Arctic, to find methods for preventing (reducing) potential damage, increasing the safety of the population and economy in the areas of the highest geocryological risks, and ensuring balanced socio-economic development in the Russian Arctic permafrost zone for the long term. The study aimed to assess the cost of fixed assets, including their most vulnerable part – buildings and structures (case study: municipalities of the Russian Arctic Asian sector). Economic sectoral structure was evaluated in accordance with the Russian Standard Industrial Classification of Economic Activities using primary statistical data – closed data from companies accounting reports. The work used statistical, cartographic, and visual-graphic methods, as well as methods for analyzing spatial information and microeconomic data. According to calculations, the Russian Arctic Asian sector concentrates the fixed assets of commercial companies with a total value of about 14.8 trillion rubles, including buildings and structures worth 10.7 trillion rubles. The obtained calculated data can be used in modeling the directions of state policy in the field of climate change adaptation and territory protection from natural hazards.

Managing human resources in information technology and business process offshoring firms operating in Asia: a literature review toward theoretically and contextually grounded research

The information technology and business process (IT&BP) offshoring sector in Asia continues to experience internal challenges and pressures from the external environment that lead to employee attrition. Despite the many human resources (HR)‐related interventions and practices, there remains a considerable turnover rate, not just within individual firms but across the entire IT&BP offshoring industry. We therefore question the current state of HR management within the sector and review the literature from 2000 to 2020. Utilizing the antecedents, decisions, and outcomes (ADO) organizing framework, we synthesize the different HR practices, their antecedents, and their outcomes. Our synthesis enables us to identify areas for future research, guided by the ADO framework, such as strengthening the theoretical grounding for the investigation of HR practices, greater contextualization regarding Asian culture, and acknowledgement of recent and emerging trends. These avenues can both build knowledge and inform practice as to how to effectively manage HR in the IT&BP offshoring sector in Asia, thereby reducing the high employee attrition rates.

The Geomagnetic Storm Time Response of the Mid Latitude Ionosphere During Solar Cycle 24

AbstractThis paper mainly assesses the geomagnetic storm time response of the Africa, America, Asia and Europe mid latitude ionosphere in relation to the variability of the total electron content during solar cycle 24. This is carried out by considering the vertical total electron content (VTEC) data derived from the Global Positioning System (GPS), the recent International Reference Ionosphere (IRI 2016) and IRI‐Extended to the Plasmasphere (IRI‐Plas 2017) models in different geomagnetic storm days during solar cycle 24 (1 June 2013, 17 March 2015, and 28 May 2017). The effects of the 1 June 2013 and 17 March 2015 (2015 St. Patrick's Day) geomagnetic storms which resulted in intensification and fluctuation of the GPS VTEC variations were significantly enhanced in the European sector. On the other hand, the effect of the storm that occurred on 28 May 2017 was mostly pronounced in the American and Asian sectors. Both models are not able to adequately respond to the effects resulting from the geomagnetic storm. The VTEC calculated by the IRI models also generally decrease on most of the hours when the storm on option is applied during the main and recovery phases. Nevertheless, at the Asian station, the IRI‐Plas 2017 VTEC values tend to increase on most of the hours during the 2015 St. Patrick's Day storm. Moreover, as a result of enhancement of the VTEC, the satellite signal propagation during the positive geomagnetic storms is largely affected by the VTEC fluctuation.

Greenland and the geopolitics of critical minerals

Greenland and the geopolitics of critical minerals

Occurrence and Variations of Middle and Low Latitude Sporadic E Layer Investigated With Longitudinal and Latitudinal Chains of Ionosondes

AbstractA longitudinal chain and a latitudinal chain of ionosondes, located at Yakutsk (129.60°E, 62.00°N), Mohe (122.37°E, 53.50°N), Beijing (116.25°E, 40.25°N), Wuhan (114.61°E, 30.53°N), Sanya (109.42°E, 18.34°N), I‐Cheon (127.54°E, 37.14°N), San Vito (17.80°E, 40.60°N), Roquest (0.50°E, 40.80°N), Millstone Hill (71.50°W, 42.60°N), and Alpena (83.56°W, 45.07°N) ionosondes, are utilized to statistically investigate the sporadic E layer (Es) occurrence rate and variation. The Es occurrence rates at all stations show a similar dependence on local time and season. However, the seasonal dependence of Es occurrence is more distinct at middle latitudes than that at low latitudes along the 120°E longitude. Results at different stations along ∼40°N latitude show much lower Es occurrence at the American sector than that at European and East Asian sectors, which is most likely because the horizontal geomagnetic field in north America is smaller than in other regions. The statistical results demonstrate that the seasonal variations of Es occurrence and strength are related to the annual variation of meteor counts. Simulation results show that the summer maximum of the ion vertical drift velocity driven by the variations of neutral densities and winds could also contribute to the seasonal variations of Es occurrence and intensity. The seasonal variations of the quasi‐6‐day and quasi‐16‐day oscillations in Es are also investigated. The seasonal variations of periodic disturbances of the Es differ between each station. Planetary waves in the MLT region cannot fully explain the seasonal variations of the periodic disturbance of Es. Solar and geomagnetic activities can also result in periodic variations of the Es.

The nighttime ionospheric response and occurrence of equatorial plasma irregularities during geomagnetic storms: a case study

Recent studies revealed that the long-lasting daytime ionospheric enhancements of Total Electron Content (TEC) were sometimes observed in the Asian sector during the recovery phase of geomagnetic storms (e.g., Lei (J Geophys Res Space Phys 123: 3217–3232, 2018), Li (J Geophys Res Space Phys 125: e2020JA028238, 2020). However, they focused only on the dayside ionosphere, and no dedicated studies have been performed to investigate the nighttime ionospheric behavior during such kinds of storm recovery phases. In this study, we focused on two geomagnetic storms that happened on 7–8 September 2017 and 25–26 August 2018, which showed the prominent daytime TEC enhancements in the Asian sector during their recovery phases, to explore the nighttime large-scale ionospheric responses as well as the small-scale Equatorial Plasma Irregularities (EPIs). It is found that during the September 2017 storm recovery phase, the nighttime ionosphere in the American sector is largely depressed, which is similar to the daytime ionospheric response in the same longitude sector; while in the Asian sector, only a small TEC increase is observed at nighttime, which is much weaker than the prominent daytime TEC enhancement in this longitude sector. During the recovery phase of the August 2018 storm, a slight TEC increase is observed on the night side at all longitudes, which is also weaker than the prominent daytime TEC enhancement. For the small-scale EPIs, they are enhanced and extended to higher latitudes during the main phase of both storms. However, during the recovery phases of the first storm, the EPIs are largely enhanced and suppressed in the Asian and American sectors, respectively, while no prominent nighttime EPIs are observed during the second storm recovery phase. The clear north–south asymmetry of equatorial ionization anomaly crests during the second storm should be responsible for the suppression of EPIs during this storm. In addition, our results also suggest that the dusk side ionospheric response could be affected by the daytime ionospheric plasma density/TEC variations during the recovery phase of geomagnetic storms, which further modulates the vertical plasma drift and plasma gradient. As a result, the growth rate of post-sunset EPIs will be enhanced or inhibited.

Assessment of long-term energy and environmental impacts of the cleaner technologies for brick production

Brick kiln sector in South Asia contributes to nearly quarter of the global bricks production. Coal is the primary fuel used by this industry and its inefficient combustion process results in harmful pollutants contributing to deteriorating air quality, health problems in local communities, and greenhouse gas emissions. The aim of this study is to investigate the impact of cleaner technologies and adoption pathways to achieve environment-friendly and energy-efficient production of bricks in Pakistan during 2019–2050. The study incorporates various timelines for (Zig-Zag Kilns) ZZKs and Vertical Shaft Brick Kilns (VSBKs) adoption, and the phasing out of conventional, Fixed Chimney Bull’s Trench Kiln (FCBTKs). Low Emissions Analysis Platform (LEAP) based numerical calculations are performed to simulate brick production from 2019–2050 for seven different scenarios incorporating an assimilated technology mix of FCBTKs, ZZKs, and VSBKs. Emissions of carbon dioxide, carbon monoxide, black carbon, methane, non-methane volatile organic compounds, particulate matter, sulfur oxides and nitrogen oxides are considered in this study. The swiftness of energy demand, and emissions reductions are greatly impacted by the elimination of the conventional FCBTKs. By adopting clearner brick manufacturing, 365.5 million tons (21.8%) of GHG emissions reduction can be achieved. The annual social cost of using FCBTKs increases from 1.02 billion $ in 2019 to 1.88 billion $ in 2050. Cumulative fuel saving potential of retrofitting to ZZKs is 157 million tons (17.7%) and it offers nearly 0.92 billion $ (51%) savings in annual social cost for year 2050. Our study finds that early adoption of ZZKs would benefit more than delayed adoption of VSBKs. However, transition to ZZK/ VSBK alone would not be sufficient to achieve net-zero carbon emissions. Carbon neutral fuels such as biomass and refuse-derived fuel (RDF) appear as an attractive option for deep decarbonization of this sector.

Utilization of Biomass to Ash: An Overview of the Potential Resources for Alternative Energy.

Climate change and the potential depletion of fossil fuels have increased international demand for alternative and renewable energy sources. In terms of the energy sector, for example, most of the South-East Asian countries (SACs) have a large number of biomass sources due to their vast forest resources and agriculture-based economies. Thus, the critical review was aimed at highlighting the overview of biomass energy in South-East Asia as a dynamically developing region, in order to obtain economic and environmental benefits from the existing sources of biomass in the world. The current review analyzed the sources of biomass, as well as their energy potential, use, and management, based on reports from different countries, published studies, and scientific articles. In SAC, the main sources of biomass were found to be coconut residues, oil palm residues, sugar cane residues, rice straw, rice husks, wood waste, and firewood. The combined annual biomass potentials in the forestry and agricultural sectors in South-East Asia were approximately over 500 million tons per year and more than 8 gigajoule of total energy potentials. The study identified the challenges and barriers to using biomass in these countries to achieve sustainable use of biomass sources and recommended sustainable approaches to using biomass energy by comparing traditional uses of biomass. Smart grid technologies have ways for solutions for better electric power production and efficient ways for distribution and transmission of electricity. Smart grids require less space and can be more easily installed when compared to traditional grids because of their versatilities. Upcoming challenges include technology optimization for the following uses of biomass energy: direct combustion of woody biomass; pyrolysis and gasification of biomass; anaerobic digestion of organic waste to produce biogas; landfill gas production direct incineration of organic waste. The barriers in this technology are emissions of carbon and nitrogen oxides, unpleasant odors, as well as the uncontrolled harvesting of biomass, which can harm nature.

A Review of Transport Policies in Support of Climate Actions in Asian Cities and Countries

Asia is one of the continents that is the most affected by the impacts of climate change. Asian countries need to take climate actions and mitigate emissions from the urban passenger transport sector. Despite some progress in improving urban mobility in Asian cities, greenhouse gas emissions from the transport sector continue to rise. Policy makers who are responsible for managing mobilities must play a major role in decarbonizing the transport sector. In this context, this paper reviews the efforts of selected Asian countries and cities towards reducing greenhouse gas emissions from the urban transport sector. It will analyze their pledges in the Nationally Determined Contributions submitted to the United Nations Framework Convention on Climate Change and will review their relevant transport sector strategies, policies, and practices. It will also look at trends in transport sector emissions and air pollution in different cities, including the short-term impacts of COVID-19. Lastly, it reviews governance issues and the roles that institutions should play to implement polices to decarbonize transport. Based on this analysis, this paper offers policy suggestions to accelerate actions, enhance cross-sectoral coordination, and move towards carbon neutrality in the transport sector in Asia.

Local and conjugate ionospheric total electron content variation during the 21 June 2020 solar eclipse

• Ionospheric TEC showed an asymmetric latitudinal depletion around totality path. • Ionospheric disturbances in both local and conjugate eclipse regions were analyzed. • Eclipse-induced ionospheric bow wave structures and TIDs were identified. This paper studies the ionospheric response to a low-latitude annular solar eclipse event on 21 June 2020 at both eclipse and conjugate regions using a dense network of Global Navigation Satellite Systems receivers, Defense Meteorological Satellite Program and Swarm satellites data, as well as ionosonde measurements over the Asian-Oceania sector. The large scale ionospheric variation and small scale wave-like perturbations during the eclipse were analyzed by using high-resolution Total Electron Content (TEC) maps and in-situ electron density/temperature data. The main results are as follows: (1) A local TEC reduction of 4–7 TEC Unit ( ∼ 30–50%) was identified along the totality path, with larger depletion in the southern edge of totality path than the northern edge. (2) The equatorial ionization anomaly in the Asian sector exhibited a complicated variation pattern with a slightly different longitudinal/local time and altitudinal response, which showed considerable TEC/ Ne depletion in the East Asian sector and at ∼ 850 km close to local afternoon during the eclipse, but a slight TEC/ Ne enhancement around the Indian sector and at ∼ 500 km in the post-eclipse periods. (3) Large ionospheric perturbations were identified that traveled at approximately the same velocity as the supersonic moon shadow, and the ionospheric bow wave features were also triggered by the solar eclipse. (4) The Oceania TEC in the Southern Hemisphere conjugate location experienced a coincident minor reduction and wave-like fluctuations during the eclipse, likely indicating some possible interconnections between the eclipse and the conjugate ionospheres.

Ionospheric Response to Sudden Stratospheric Warming Events Across Longitudes During Solar Cycle 24

AbstractSolar cycle 24 from December 2008 to December 2019 had an unusual progression and was the weakest cycle in a century, providing an ideal scenario to study perceivable effect of wave forcing from lower atmosphere. This study examines the ionospheric response to meteorological phenomenon of sudden stratospheric warming (SSW) during solar cycle 24 (Arctic winter 2008/2009 to 2018/2019) using Global Positioning System‐derived total electron content (VTEC) and its deviation from monthly median (ΔVTEC) for four longitudinal chains. Each chain comprises eight stations, covering varied latitudes in both hemispheres. A longitude‐ and latitude‐dependent response of VTEC is observed within ∼3 weeks of peak polar stratospheric temperature anomaly (ΔTmax), with maximum variations seen for low‐latitude stations at American and Australian‐East Asian sectors. It is seen that variations during minor warming events are comparable or at times even larger than during major warming events. These responses increase with an increase in solar activity, with major SSW events primarily seen during moderate and low solar activity periods and minor SSW during high solar activity period. Under similar ionizing conditions, a quite similar ionospheric response is observed irrespective of ΔTmax and of SSW type (major or minor); however, under similar SSW strength, no prominent pattern in ionospheric response is observed. Latitude‐dependent semidiurnal ionospheric behavior is observed for only a few events. This vertical coupling between lower and upper atmosphere during SSW is predominantly influenced by 13–16 days periodicities in VTEC, along with other periodicities of 9, 7, 5, and 3 days.

Characterization of seasonal and annual variation of horizontal component of magnetic field in africa and asia regions

This study considered the horizontal component of the magnetic field, H, which is a characteristic of Equatorial Electrojet (EEJ). Using Magnetic Data Acquisition System (MAGDAS) data preserved for the year 2009, variations in H strength were determined in 10 stations in Africa and Asia sector. The seasonal and annual fluctuations in the H-component of the Earth’s magnetic field were studied using hourly data of the horizontal magnetic field component. For the hourly fluctuation, the baseline values of H were estimated using the average values around local midnight hours between 2300 and 0200 local-time (LT) and subtracted from other hourly values; for seasonal and yearly analysis, the monthly and annual averages were computed. In all seasons, seasonal variations were higher in equatorial stations than in anti-equatorial stations, while maximum values of SqH were recorded in the equinoctial season, with an annual highest peak value of 70.96 nT in Langkawi (LKW; 6.30°S, 99.78°E) and the lowest peak value of 27.45 nT in Cooktown (CKT; 15.48°N, 145.25°E) both at 1300 LT.

Atmospheric and ionospheric disturbances associated with the M > 6 earthquakes in the East Asian sector: A case study of two consecutive earthquakes in Taiwan

The phenomenon of Lithosphere-Ionosphere coupling is a popular topic for researchers for the last two decades. This study aims to analyze the seismo-ionospheric anomalies (SIAs) in East Asia induced by the M > 6 earthquakes (EQs) from Total Electron Content (TEC) of permanent IGS stations operating around the vicinity of the corresponding epicenters by considering a case study of two successive EQs from Taiwan. Our results showed remarkable TEC enhancements one day before both impending EQs during quiet geomagnetic activity (Kp less than 3, Dst ≥ −20), where the variations were found one day before each EQ during UT = 02–08 (LT = 10–16) hours in the form of differential TEC (dTEC). On the other hand, V-shaped gradual decreases in temporal atmospheric parameters took place one day before the M 6.1 EQ that gradually decreased till the M 6.4 EQ day before turning back to normal. The anomaly maps of geopotential height and surface air temperature showed intense decreases and the consequent OLR enhancements right along the edge of the Philippine Sea plate in the northwest direction. Furthermore, we observed a distinctive phenomenon of equatorial ionization anomaly (EIA) enhancement in the latitudinal GIM-TEC profiles near the epicentral longitude, where the EIA structure modified the shape as a double crust structure with a trough near to the equator that testifies the generation of the seismogenic electric field. Our multi-precursory study is another contribution in the acknowledgment of LAI coupling (Lithosphere, Atmosphere, Ionosphere) hypothesis in the prediction of the future EQs.

The convergence of financial sector in Asia

This study aims to identify the convergence of financial sector development and the effect of macroeconomic variables on each financial sector development indicator in Asia. The sample used consists of 24 countries in Asia during the period 2010-2018. Identification of convergence using ?-convergence absolute and conditional. Indicators are used to represent the development of the financial sector namely private credit, liquid liabilities, stock market capitalization, and stock market turnover. Empirical evidence was based on the Generalized Method of Moment (GMM) estimation technique. The results showed that there was convergence in Asia and that macroeconomic variables had a significant effect on the development of the financial sector.

Mapping the coverage, availability and uptake of External Quality Assessment programmes across One Health sectors in Asia.

IntroductionEstablishing effective external quality assessment (EQA) programmes is an important element in ensuring the quality of, and building capacity for, antimicrobial resistance (AMR) laboratory surveillance.ObjectivesTo understand the current coverage of, and challenges to participation in, EQAs in National Reference Laboratories (NRLs) across One Health (OH) sectors in Asia.MethodsCurrent EQA coverage was evaluated through desktop review, online surveys and interviews of both EQA participants and providers. EQA coverage was mapped and summarized by laboratory type and ‘readiness’ level and identified challenges evaluated qualitatively.ResultsOf the 31 identified NRLs [16 Human Health (HH) and 15 Animal/Food Safety laboratories (A/FS)], 14 HH and 7 A/FS laboratories currently participated in international EQA schemes and several participated in two or more different schemes. Seven laboratories were currently not participating in any EQA scheme and two of these (one HH and one A/FS) do not currently perform microbiology; six HH NRLs provided national EQAs. Of the eight surveyed international EQA providers, three were based in Asia and all offered varying programmes in terms of pathogens, frequency and support mechanisms for reporting and follow-up. Only one provider currently served laboratories across all OH sectors.ConclusionsThe current coverage of EQA programmes for AMR in Asia was heterogeneous across countries but especially across OH sectors. This updated overview of the coverage and challenges associated with participation in, and provision of, EQAs for AMR suggest the benefit and relevance of introducing one comprehensive and high-quality EQA programme across OH sectors in Asia.

Wellness comes in salty water: thalassotherapy spas and service level of satisfaction

ABSTRACT The lucrative and rapid expansion of the wellness tourism sector in Europe and Asia has led to intense competition among wellness tourism destinations. This study investigates the business in five major nations: China, Japan, Russia, Germany, and Italy, which together accounts for 77% of global revenue pre-pandemic from the thalassotherapy spas and resort industry. We analysed TripAdvisor’s 3116 tourists’ review responses representing five-star thalassotherapy facilities. The primary drivers of an excellent service include hotel room facilities and thalasso-treatments with seawater. We identify a semantic clustering linked to thalassotherapy spa attractiveness and determine attributes that are pertinent to satisfaction of wellness-seeking tourists. The current study contributes to the sparse literature on wellness tourism specifically relating to thalassotherapy spas and the level of satisfaction associated with the service. The study suggests practical advice to address the negative effects of customer dissatisfaction on services that can overshadow the positive effects of satisfaction. Highlights The study identifies thalassotherapy spa attractiveness based on the semantic clustering The data is based on tourists’ reviews that include some type of therapy Thalassotherapy spas in this study represent two-thirds of the world revenue This study identifies the key factors of satisfaction and dissatisfaction in thalassotherapy

A matrix approach to tropical marine ecosystem service assessments in South east Asia

Ecosystem service assessments are increasingly used to support natural resource management, but there is a bias in their application towards terrestrial systems and higher income countries. Tropical marine applications are particularly scarce, especially in SE Asia. Given the growing coastal population and expansion in blue economy sectors in SE Asia, evidence to support effective marine planning, such as ecosystem service assessments, is urgently needed. Data deficiencies for marine systems, especially (but not only) in lower income countries is a significant obstacle for ecosystem service assessments. To overcome this, we develop an ecosystem service potential matrix which combines evidence taken from an extensive literature review together with expert opinion. The matrix includes both natural and modified habitats as the service providing units. The ecosystem service potential for habitats are scored at the macro level (e.g. mangrove) due to insufficient evidence to score micro-habitats (e.g. fringe, basin or riverine mangroves). The majority of evidence is available for biogenic habitats (mangroves, coral reefs and seagrass meadows) with comparatively little for sedimentary habitats. While provisioning, regulating and cultural services are scored, published evidence is more readily available for provisioning and regulating services. Confidence scores, indicating the uncertainty in the ecosystem service potential scores are included in the matrix. To our knowledge this is the first attempt to systematically capture the provision of ecosystem services from tropical marine habitats. Although initially developed for four marine biosphere reserves and protected areas in SE Asia, the generic nature of the evidence included suggests that the matrix constitutes a valuable baseline for marine ecosystem service assessments within SE Asia and provides a robust foundation for development in future work.

Coupled investigations of ionosphere variations over European and Japanese regions: observations, comparative analysis, and validation of models and facilities

This paper presents the results of a coordinated measurement campaign with ground based and satellite observations over European and Japanese regions during September 5–6, 2017. Two incoherent scatter radars, two satellite missions, International Reference Ionosphere (IRI-2016) empirical model, and Field Line Interhemispheric Plasma (FLIP) physical model were employed to examine the regular behavior of the F2-layer peak height and density and the topside ionosphere electron density, electron, and ion temperatures as well as traveling ionospheric disturbances (TIDs). The daily ionospheric variations over Kharkiv and Shigaraki exhibited similar behavior qualitatively and quantitatively. The results show that none of the empirical IRI-2016 models of F2-layer peak height, topside electron density, and temperature can be preferred for predicting the key qualitative features of variations in ionospheric plasma parameters over Kharkiv and Shigaraki. The likely reason is rapid day to day changes in solar activity and series of moderate enhancements of magnetic activity occurring in the observation period and preceding days. Compared with IRI-2016 model, the FLIP physical model was shown to provide the best agreement with the observations when constrained to follow the observed diurnal variations of F2-layer peak height both over Europe and Japan. This paper presents the first direct comparison of the mid-latitude electron density measured by the Swarm satellite with incoherent scatter radar data and it confirms the high quality of the space-borne data. For the first time, evidence of the possible need to increase the neutral hydrogen density in NRLMSISE-00 model by at least a factor of 2 was obtained for the Asian longitudinal sector. The TIDs, which have predominant periods of about 50 min over Europe and 80 min over Japan, were detected, likely caused by passage of the solar terminator. Such a difference in the periods could indicate regional features and is the topic for further research.

Board Structure Problem in Aviation Companies: The Relationship of Political Connection and Multiple Directorship on Firm Performance

This study analyzes the relationship between the political connection and multiple directorships of aviation companies’ board members and their firm performance. This research will focus on companies in the aviation sector on a broader subsector than previous studies. It will help the shareholder of the aviation companies determine board structure policies and evaluate the implementations conducted so far. This research uses descriptive statistics and regression analysis for the panel data model. Moreover, this study uses a purposive sampling technique secondary data from the aviation company’s annual reports in the Asia continent for the 2016-2020 period. The results show that the multiple directorships negatively affect firm performance in aviation companies while the board’s political connections positively affect firm performance, measured by its Return on Equity (ROE). In contrast, the multiple directorships and political connections do not impact aviation companies' firm performance measured by their Return on Assets (ROA). Overall, this study in the Asia continent asserts the previous study where the political connection positively affects the airline’s firm performance in the US. The result can support the corporate governance practice of deciding board structure in the aviation sectors in Asia in terms of political connection and multiple directorships.DOI: 10.26905/jkdp.v25i3.5892