• Maritime Security
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• v.1 no.1
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• pp.241-271
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• 2020

The military technology currently receiving the most attention is the hypersonic missile. hypersonic is faster than the speed of sound or Mach 5+. The vast majority of the ballistic missiles that it inspired achieved hypersonic speeds as they fell from the sky. Rather than speed, today's renewed attention to hypersonic weapons owes to developments that enable controlled flight. These new systems have two sub-varieties: hypersonic glide vehicles and hypersonic cruise missiles. Hypersonic weapons could challenge detection and defense due to their speed, maneuverability, and low altitude of flight. The fundamental question of this study is: 'What effect will the hypersonic missile have on the maritime strategy?' It is quite prudent to analyze and predict the impact of technology in the development stage on strategy in advance. However, strategy is essential because it affect future force construction. hypersonic missiles act as a limiting factor in securing sea control. The high speed and powerful destructive power of the hypersonic missile are not only difficult to intercept, but it also causes massive ship damage at a single shot. As a result, it is analyzed that the Securing sea control will be as difficult as the capacity of sea denial will be improved geographically and qualitatively. In addition, the concept of Fortress Fleet, which was criticized for its passive strategy in the past, could be reborn in a modern era. There are maritime power projection/defence, SLOC attack/defence in exploiting sea control. The effects of hypersonic missiles on exploiting sea control could be seen as both limiting and opportunity factors.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.211-219
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• 2020

This paper examines in depth the UN's disaster risk reduction system and framework that affect a country's disaster safety strategy and focuse on identifying the global trends in disaster risk reduction that have emerged in the Hyogo and the Sendai Framework, a disaster risk reduction strategy proposed by the UN since 2000. For this aim it attempts a theoretical review based on collecting a variety of domestic and international literatures, draws meaningful implications and suggests alternatives to a national disaster risk reduction policy. According to the analysis, the UN disaster risk reduction mechanism is UNISDR, the Secretariat is UNDRR, and the SRSG represents it, and the Sendai Framework, developed from the Hyogo Code of Conduct, a global strategy which has been for disaster safety for the past decade, will lead global disaster safety for the next decade. The policy implications drawn from the analysis of both strategies are the emphasis on consistent international coordination, strengthening resilience and an integrated and comprehensive approach. In conclusion, this paper proposes the need for a disaster risk reduction strategy to establish a resilience reinforcement system to proactively identify and cope with risk factors and to minimize impacts, to promote the coordination of international coordination and cooperation at the government level.

• Science of Emotion and Sensibility
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• v.23 no.1
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• pp.89-102
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• 2020

This study aimed to compare the effects of two emotion regulation strategies, namely, cognitive reappraisal and expressive suppression in female college students. Specifically, the effects of these two emotion regulation strategies were tested and the intrapersonal factors related to the effects of these strategies were explored. The participants included 60 female college students. In Study 1, 40 participants were randomly assigned to each of the two different strategy groups, i.e., a between-subject design was employed. In Study 2, 20 participants were asked to use both strategies to regulate their emotion, i.e., a within-subject design was employed. The results revealed that both emotion regulation strategies effectively reduced negative emotion of emotional stimuli. However, the use of emotion regulation assessed with a questionnaire was not matched to the actual usage of regulation strategies examined with a task. Finally, the use of a suppression strategy was related to the extroversion psychological adaptive variable. Our findings suggest that the subjective assessment of the use of an emotion regulation strategy may not be the same as the actual use of an emotion regulation strategy. Furthermore, we demonstrated that when participants have an option to use both strategies, the cognitive reappraisal is more functional than expression suppression. This concurs with the previous findings on the effects of emotion regulation strategies.

• Geophysics and Geophysical Exploration
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• v.23 no.1
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• pp.38-49
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• 2020

Full-waveform inversion (FWI) is an optimization process of fitting observed and modeled data to reconstruct high-resolution subsurface physical models. In acoustic FWI (AFWI), pressure data acquired using a marine streamer has mainly been used to reconstruct the subsurface P-wave velocity models. With recent advances in marine seismic-acquisition techniques, acquiring multi-component data in marine environments have become increasingly common. Thus, AFWI strategies must be developed to effectively use marine multi-component data. Herein, we proposed an AFWI strategy using horizontal and vertical particle-acceleration data. By analyzing the modeled acoustic data and conducting sensitivity kernel analysis, we first investigated the characteristics of each data component using AFWI. Common-shot gathers show that direct, diving, and reflection waves appearing in the pressure data are separated in each component of the particle-acceleration data. Sensitivity kernel analyses show that the horizontal particle-acceleration wavefields typically contribute to the recovery of the long-wavelength structures in the shallow part of the model, and the vertical particle-acceleration wavefields are generally required to reconstruct long- and short-wavelength structures in the deep parts and over the whole area of a given model. Finally, we present a sequential-inversion strategy for using the particle-acceleration wavefields. We believe that this approach can be used to reconstruct a reasonable P-wave velocity model, even when the pressure data is not available.

• Journal of Contemporary Eastern Asia
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• v.20 no.2
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• pp.63-84
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• 2021

The present study was conducted to understand the turmoil effects of COVID-19 pandemic on the Malaysian stock market during the different periods of the Movement Control Order (MCO). The present study was based on the secondary data extracted from the DataStream and Bloomberg from 2nd January 2020 to 29th May 2020 to evaluate the effects of COVID-19 pandemic on the Malaysian stock market. The findings suggested that during the different periods of the Movement Control Order (MCO) from the 1st January to 29th May 2020, the COVID-19 pandemic adversely affected the performance of KLCI index and all sectoral indices. The weakest performance indices were energy, property, and finance while the least affected indices were healthcare, technology, telecommunications, and media. This paper provides a review of the impacts of COVID-19 pandemic on the Malaysian stock market throughout the different periods of MCO.

• Journal of Contemporary Eastern Asia
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• v.19 no.2
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• pp.148-168
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• 2020

In April, 2020, amid widespread fear of a second wave of infections of the novel coronavirus in China, local authorities in Guangzhou cracked down on the city's black population, resulting in mass evictions of Africans. The incident raises several questions about racism in China. How should we interpret this heavy-handed treatment of black people? Was this an isolated incident? What motivated such operations? In this article, I explain social control of Guangzhou's African communities as a problem of municipal politics. What underlies the government's heavy handed approach, I argue, are those communities' ties to rurality, which constitute a roadblock in the city's urban upgrade. Using Dengfeng Village, one of the best known African communities in China, as a case study, I show that efforts to upgrade the area by the local state and the real estate industry were frustrated by the community's status as an urban village. Africans, whom Chinese have historically associated with rurality, are seen as contributing to a space that has long been stigmatized as a spatial manifestation of rural people's lack of self-discipline. To better reveal the interconnection between social control and urban politics, I place official action in context of the history of the community's formation and the lived experience. This analysis of Dengfeng applies to various extents to other major African communities in Guangzhou.

• Journal of Environmental Science International
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• v.30 no.6
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• pp.475-485
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• 2021

This research investigated the characteristics of fine particles during cold front passage in Busan, on March 19, 2020. The cold front speed was 17.4 m/s (about 63k km/hr), moving from the northwest to the southeast, and with a width of about 64 km. The backward trajectory analysis showed that a southern sea air parcel flowed into Busan before the cold front passage, carrying continental materials from China transported into Busan after cold front passage. The PM₁₀ concentration in Busan showed a rapid increase after passing through the cold front, with PM_2.5 showing a high concentration during cold front passage. The PM_2.5/PM₁₀ ratio was 0.10 - 0.30. When the cold front passed, SO₄^2-, NO₃^-, Ca²⁺, NH₄⁺, Na⁺, and K⁺ in PM_2.5 showed a rapid increase, with SO₄^2- showing the most significant increase. These results indicated that understanding the characteristics of fine particles during cold front passage in Busan could provide insight into establishing a strategy to control urban air quality.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.7
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• pp.53-62
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• 2022

Commercial banks have a significant impact on the economy of Vietnam because they provide the majority of transactional capital. Therefore, the operational efficiency of commercial banks is a viral topic for the study of the Vietnamese banking system. The research aims to examine the efficiency and inefficiency of joint-stock commercial banks in Vietnam from 2016 to 2020 and then classify them into the efficient group and inefficient group. The study employs the time series data of 29 joint-stock commercial banks during the period 2016-2020. Based on the data collected from the annual audited financial statements of 29 Vietnamese joint-stock commercial banks, the authors select input and output variables for the standard DEA models and anti-efficient DEA models. This research uses two stages, first, by applying the standard DEA model, we investigate the efficient banks; second, by employing the anti-efficient DEA model, we find out the inefficient banks. The results reveal that the average efficiency score of 29 joint-stock commercial banks tends to increase in the period 2016-2018 and decrease gradually in the period 2019-2020. The findings of this study suggest that several small and medium-sized banks in the Vietnamese banking sector have both promising and risky performances and the efficiency of state-owned commercial banks has also improved significantly during the study period.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.46.1-46.1
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• 2020

DEEP-South (DEep Ecliptic Patrol of the Southern Sky) team will start the 2nd phase of KMTNet observation in Oct 2020. The DEEP-South observation mainly consists of three survey modes: (1) Activity survey (AS) that aims at finding active phenomena of small Solar System bodies. (2) Light curve survey (LS) targets to discover and characterize light variations of asteroids. And (3) Deep drilling survey (DS) focuses on the objects beyond the orbit of Jupiter (Centaurus and trans-Neptunian objects) as well as near Earth asteroids. For asteroid family (AF) studies and target of opportunity (TO) observations for urgent photometric follow-up, targeted mode will also be used. DEEP-South team is awarded 7.0% of the telescope time at each site every year from Oct 2020 to Sep 2023 in the 2nd phase of KMTNet operation which corresponds to about 75 full nights a year for the network. In this presentation, we will introduce our survey strategy and observation plan.

• Journal of Intelligence and Information Systems
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• v.26 no.1
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• pp.119-133
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• 2020

Fama asserted that in an efficient market, we can't make a trading rule that consistently outperforms the average stock market returns. This study aims to suggest a machine learning algorithm to improve the trading performance of an intraday short volatility strategy applying asymmetric volatility spillover effect, and analyze its trading performance improvement. Generally stock market volatility has a negative relation with stock market return and the Korean stock market volatility is influenced by the US stock market volatility. This volatility spillover effect is asymmetric. The asymmetric volatility spillover effect refers to the phenomenon that the US stock market volatility up and down differently influence the next day's volatility of the Korean stock market. We collected the S&P 500 index, VIX, KOSPI 200 index, and V-KOSPI 200 from 2008 to 2018. We found the negative relation between the S&P 500 and VIX, and the KOSPI 200 and V-KOSPI 200. We also documented the strong volatility spillover effect from the VIX to the V-KOSPI 200. Interestingly, the asymmetric volatility spillover was also found. Whereas the VIX up is fully reflected in the opening volatility of the V-KOSPI 200, the VIX down influences partially in the opening volatility and its influence lasts to the Korean market close. If the stock market is efficient, there is no reason why there exists the asymmetric volatility spillover effect. It is a counter example of the efficient market hypothesis. To utilize this type of anomalous volatility spillover pattern, we analyzed the intraday volatility selling strategy. This strategy sells short the Korean volatility market in the morning after the US stock market volatility closes down and takes no position in the volatility market after the VIX closes up. It produced profit every year between 2008 and 2018 and the percent profitable is 68%. The trading performance showed the higher average annual return of 129% relative to the benchmark average annual return of 33%. The maximum draw down, MDD, is -41%, which is lower than that of benchmark -101%. The Sharpe ratio 0.32 of SVS strategy is much greater than the Sharpe ratio 0.08 of the Benchmark strategy. The Sharpe ratio simultaneously considers return and risk and is calculated as return divided by risk. Therefore, high Sharpe ratio means high performance when comparing different strategies with different risk and return structure. Real world trading gives rise to the trading costs including brokerage cost and slippage cost. When the trading cost is considered, the performance difference between 76% and -10% average annual returns becomes clear. To improve the performance of the suggested volatility trading strategy, we used the well-known SVM algorithm. Input variables include the VIX close to close return at day t-1, the VIX open to close return at day t-1, the VK open return at day t, and output is the up and down classification of the VK open to close return at day t. The training period is from 2008 to 2014 and the testing period is from 2015 to 2018. The kernel functions are linear function, radial basis function, and polynomial function. We suggested the modified-short volatility strategy that sells the VK in the morning when the SVM output is Down and takes no position when the SVM output is Up. The trading performance was remarkably improved. The 5-year testing period trading results of the m-SVS strategy showed very high profit and low risk relative to the benchmark SVS strategy. The annual return of the m-SVS strategy is 123% and it is higher than that of SVS strategy. The risk factor, MDD, was also significantly improved from -41% to -29%.