• Title/Summary/Keyword: asymmetry

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Ergonomic Evaluation of Young Agricultural Operators Using Handle Equipment Through Electromyography and Vibrations Analysis Between the Fingers

  • Federico Roggio;Ermanno Vitale;Veronica Filetti;Venerando Rapisarda;Giuseppe Musumeci;Elio Romano
    • Safety and Health at Work
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    • v.13 no.4
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    • pp.440-447
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    • 2022
  • Background: Agricultural handle equipment is present on all production areas' farms. They are handy and portable; however, excessive use can lead to acute traumas or accidental injuries. Repetitive movements, awkward postures, and hand-arm vibrations predispose them to pain and work-related musculoskeletal disorders. The purpose of this study was to observe the interaction of handle equipment in terms of electromyographic activity and analyze the postural work-related alterations. Materials and methods: Twenty male agricultural operators, mean age 24±1.54 years, underwent the electromyographic analysis testing their muscular activities with a brushcutter, electric saw, and hedge trimmer in four different test conditions. Results: The brushcutter proved to be the agricultural handle equipment with the higher mean frequency (3.37±0.38 Hz) and root mean square (5.25±1.24 ms-2). Furthermore, the digital postural analysis showed a general asymmetry of the main arm and the respective side of the trunk. The head resulted right inclined in the anterior frontal plane by 5.7°±1.2°; the right scapula lower than the left in the posterior frontal plane (8.5°±1.8°), and a working trunk inclination of 34.15°±5.7°. Conclusions: Vibrations of handle equipment and awkward working postures represent a risk for agricultural operators. Preventive measures are required to avoid young operators from experiencing musculoskeletal disorders all lifelong.

HI gas kinematics of paired galaxies in the cluster environment from ASKAP pilot observations

  • Kim, Shin-Jeong;Oh, Se-Heon;Kim, Minsu;Park, Hye-Jin;Kim, Shinna
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.70.1-70.1
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    • 2021
  • We examine the HI gas kinematics and distributions of galaxy pairs in group or cluster environments from high-resolution Australian Square Kilometer Array Pathfinder (ASKAP) WALLABY pilot observations. We use 32 well-resolved close pair galaxies from the Hydra, Norma, and NGC 4636, two clusters and a group of which are identified by their spectroscopy information and additional visual inspection. We perform profile decomposition of HI velocity profiles of the galaxies using a new tool, BAYGAUD which allows us to separate a line-of-sight velocity profile into an optimal number of Gaussian components based on Bayesian MCMC techniques. Then, we construct super profiles via stacking of individual HI velocity profiles after aligning their central velocities. We fit a model which consists of double Gaussian components to the super profiles, and classify them as kinematically cold and warm HI gas components with respect to their velocity dispersions, narrower or wider 𝜎, respectively. The kinematically cold HI gas reservoir (M_cold/M_HI) of the paired galaxies is found to be relatively higher than that of unpaired control samples in the clusters and the group, showing a positive correlation with the HI mass in general. Additionally, we quantify the gravitational instability of the HI gas disk of the sample galaxies using their Toomre Q parameters and HI morphological disturbances. While no significant difference is found for the Q parameter values between the paired and unpaired galaxies, the paired galaxies tend to have larger HI asymmetry values which are derived using their moment0 map compared to those of the non-paired control sample galaxies in the distribution.

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A Study on the Linkage Method of Address Information with Public Land Registries to Protect Tenants' Rights - Focusing on the Road Name Address Book - (세입자 보호를 위한 공적 장부의 주소정보 연계방안 연구 - 도로명주소대장을 중심으로 -)

  • Kim, Jeong-Hyeon;Kang, Seung-Mo;Lim, Mi-Hwa
    • Journal of Cadastre & Land InformatiX
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    • v.53 no.1
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    • pp.65-81
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    • 2023
  • In recent times, there has been a surge in media coverage regarding fraudulent real estate lease scams. These scams have been attributed to speculators who made imprudent gap investments, in response to the sudden decline in real estate prices. The government has established new measures to safeguard tenants and prevent fraudulent real estate lease schemes in response to the growing incidence of tenants falling victim to such scams. Although there have been active research efforts on laws and regulations aimed at protecting tenants, such as the Tenant Protection Act and leasehold registration orders, there is an urgent need for research on the consistency of information across public ledgers, as real estate fraud has surged due to information asymmetry among these ledgers. This study aims to explore matching methodologies using matching keys for building information from real estate-related public ledgers, such as the building register and the road name address ledger, as well as to examine ways to integrate these ledgers with other public ledgers.

Observational Studies on Evolved Stars Using KVN and KaVA/EAVN

  • Cho, Se-Hyung;Yun, Youngjoo;Imai, Hiroshi
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.51.1-51.1
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    • 2019
  • At the commissioning phase of KVN from 2009 to 2013, single-dish survey and monitoring observations were performed toward about 1000 evolved stars and about 60 relatively strong SiO and H2O maser sources respectively. Based on these single-dish results and VLBI feasibility test observations at K/Q/W/D bands in 2014, KVN Key Science Project (KSP) has started from 2015 and will be completed in 2019 as KSP phase I. Here we present the overview of observational studies on evolved stars using KVN. In KSP phase I, we have focused on nine KSP sources which show a successful astrometrically registered maps of SiO and H2O masers using the source frequency phase referencing method. We aim at investigating the spatial structure and dynamical effect from 43/42/86/129 GHz SiO to 22 GHz H2O maser regions associated with a stellar pulsation and development of asymmetry in circumstellar envelopes. Using the combined network KaVA (KVN+Japanese VLBI network VERA), KaVA Large Program titled on "Expanded Study on Stellar Masers: ESTEMA Phase I" was performed from 2015 to 2016. Based on ESTEMA Phase I, EAVN Large Program titled on "EAVN Synthesis of Stellar Maser Animations: ESTEMA Phase II" was also performed from 2018. The ESTEMA II project aims to publish composite animations of circumstellar H2O and SiO masers, which taken from up to 6 long-period variable stars with a variety of the pulsation periods (333-1000 days). The animations will exhibit the three-dimensional kinematics of the maser gas clumps with complexity caused by stellar pulsation-driven shock waves and anisotropy of clump ejections from the stellar surface. Adding three EAVN telescopes (Tianma 65m, Nanshan 26m and NRO 45m telescopes) with KaVA always secures the high quality of the maser image frames through the monitoring program.

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Investment and Firm Performance Variability

  • Hee-Jung Yeo
    • Journal of Korea Trade
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    • v.27 no.1
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    • pp.60-78
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    • 2023
  • Purpose - The study analyzed 90 online firms worldwise and observed them for ten years to investigate their investments and firm performance variabilities. This study attemped to verify the existence of agency problems in online firms. Through this, the paper intends to expand the scope of research in the fields of investment and firm value both empirically and in theory. This study also attempted to supplement the insufficient logic of previous studies by analyzing the relationship between investment and profitability. Design/methodology - In this study, the investment is subdivided into over-, under-, and neutral investments, and an empirical analysis of the firm performance was conducted. As investment generally has long-term effects, the impact of a firm's investment on future firm performance and variabilities in firm performance was considered over the short-and medium-term period. Findings - It was found that there was a negative relationship between firms with an overinvestment and future firm performance. Underinvestment has no clear statistically significant results on firm performance. This implies that overinvestment causes more reduction in future firm performance than underinvestment. It was also found that underinvestment and overinvestment significantly increased the variability of firm performance. A positive significance was found between under- and over- investment with a variability of 3 years and overinvestment with a variability of 4 years in the future. A negative relationship was found between neutral investment propensity and future performance variabilities. Neutral investment has less effect on the future performance variability of a firm than a firm's overinvestment and underinvestment. For online firms, underinvestment and overinvestment have a greater effect on the firm's future performance variability than neutral investment. Originality/value - The agency theory predicts that information asymmetry and adverse selection problems exacerbate conflicts of interest among stakeholders, thus firm performance. The study contributed to accumulating research on online firms that are currently underexplored by analyzing the investment behavior of major firms in the online industry.

The Characteristics of ESG and Effect on Corporate Value of Chinese Firms (중국 기업의 ESG의 특징과 기업가치에 대한 영향)

  • Shao-Wei Xue;Jae-Hyun Lee
    • Asia-Pacific Journal of Business
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    • v.14 no.1
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    • pp.131-148
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    • 2023
  • Purpose - Since the 2020s, the management philosophy of Chinese firms' ESG has been rapidly established under the leadership of the Chinese government. We empirically analyze the ESG characteristics and effects on corporate value of Chinese firms. Design/methodology/approach - Using OLS and random effect panel regression analysis, we identify ESG determinants. In analyzing the impact on corporate value, likewise a large number of literatures, we adopt a 2SLS methodology using instrumental variables in the reason of endogeneity between ESG and firm value. We analyze using the G2SLS methodology, which is improving the efficiency of the estimation coefficients along with 2SLS. Findings - We find that ESG ratings are high in state-owned and foreign capital invested companies, ESG ratings are low in companies with a high proportion of non-floating stocks which implies information asymmetry. However, there are no significance in the institutional investor's, the major 10 largest shareholders' and manager's ownership. Furthermore, we can support most of the hypotheses that ESG ratings will be high in companies with high management performance. ESG ratings are significantly higher in companies with high ROA, rich in cash asset, low debt ratio, and large size. we strongly support the hypothesis that the higher the ESG rating, the higher the firm value, and ESG has a moderating effect on state-owned companies, non-floating shares, the ownership of institutional investors, manager, and the 10 major shareholder. In particular, state-owned companies, the proportion of non-floating shares, and the ownership of the 10 major shareholders have a negative impact on firm value, however, ESG attenuates this negative effect. Research implications or Originality - This study looks forward to enhancing our understanding of ESG characteristics in East Asia.

Classification of Service Attributes and Strategic Customer Service Management based on the Asymmetric and Non-linear Relationship between Service Attributes and Customer Satisfaction (서비스 속성과 고객만족과의 비대칭적, 비선형적 관계에 근거한 서비스 속성 분류와 전략적 고객서비스 경영)

  • Park, Jung-Young;Lee, Gye-Hee
    • Journal of the Korean Society of Food Culture
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    • v.23 no.5
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    • pp.605-615
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    • 2008
  • The principal objective of this study was to categorize service attributes on the basis of the asymmetric and non-linear relationship existing between service attributes and customer satisfaction. Researchers generally assume that service attribute performances and customer satisfaction are both symmetrical and linear. That is to say, improvements in attribute performance will inevitably result in increased customer satisfaction. However, this is not always the case. Certain attributes have been shown not to create satisfaction even when improved, and others do not create dissatisfaction even when their performance ratings become negative. Understanding this relationship is crucial not only to researchers, but also to service managers. Service managers can arrange their priorities with regard to which attributes must be improved or promoted first, in an environment of limited technical, financial, and human resources. Many studies into this asymmetric and non-linear relationship have recently been conducted, beginning with Herzberg's motivation-hygiene theory (1976) and the disconfirmation theory, which was eventually developed into Kano's model (1984). This study attempted to determine the impact level of service attributes on incidents of satisfaction or dissatisfaction. It used 30 service attributes generated by Park (2008) in the CIT research into family restaurants. The data were collected from 600 participants, 300 incidences of satisfaction and 300 incidents of dissatisfaction, via an online survey. The t-test was used to confirm the difference between the satisfaction group's and dissatisfaction group's attributes. 11 attributes were found to be significant at a level of p>0.05. This indicates that the 11 attributes exerted different impacts on satisfaction and dissatisfaction, which confirmed the asymmetric and non-linear relationship. 14 attributes were categorized into the core service, 1 attribute into the quality service, 7 attributes into the basic service, and 8 attributes into the neutral service. Strategic customer service management was recommended for the 'A' family restaurant as an example, on the basis of the asymmetric and non-linear relationship and the characteristics of the four service factors.

"There Was No Violence, But...": Study on Coercive Control of Intimate Partner Violence and Reconceptualization of Domestic Violence ("폭력이 있었던 것은 아니지만..." : 친밀한 관계에서의 강압적 통제와 가정폭력 재개념화를 위한 연구)

  • Heo, Min-Sook
    • Issues in Feminism
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    • v.12 no.2
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    • pp.69-103
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    • 2012
  • By reviewing relatively recent theory of coercive control, which considers gender as a key concept to conceptualize domestic violence, this article explores battered women's experiences with police responses and institutional law enforcement. Using data and interviews from Korea Women's Hotline, this article analyzes the effects of state intervention which fails to support battered women and sends a message to the community that domestic violence is not such a serious crime. Specifically, this study found some problematic responses and attitudes of police and legal system: first, police is equating domestic violence with physical attacks or serious harms. Second, police and law enforcement personnel blame victims based on her gender performance or gender roles. Third, by individualizing the problem of domestic violence, state intervention ignores important structural factors that cause and perpetuate it. Finally, police and the justice system disempower and discourage battered women by exacerbating victim's fears and risks. Viewing domestic violence as a liberty crime, this study concludes that enhanced understanding of the nature of domestic violence only can contribute to solving the problem and protecting women's human rights.

Asymmetric volatility models with non-zero origin shifted from zero : Proposal and application (원점이 이동한 비대칭-변동성 모형의 제안 및 응용)

  • Ye Jin Lee;Sun Young Hwang;Sung Duck Lee
    • The Korean Journal of Applied Statistics
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    • v.36 no.6
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    • pp.561-571
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    • 2023
  • Volatility of a time series is defined as the conditional variance on the past information. In particular, for financial time series, volatility is regarded as a time-varying measure of risk for the financial series. To capture the intrinsic asymmetry in the risk of financial series, various asymmetric volatility processes including threshold-ARCH (TARCH, for short) have been proposed in the literature (see, for instance, Choi et al., 2012). This paper proposes a volatility function featuring non-zero origin in which the origin of the volatility is shifted from the zero and therefore the resulting volatility function is certainly asymmetric around zero and achieves the minimum at a non-zero (rather than zero) point. To validate the proposed volatility function, we analyze the Korea stock prices index (KOSPI) time series during the Covid-19 pandemic period for which origin shift to the left of the zero in volatility is shown to be apparent using the minimum AIC as well as via parametric bootstrap verification.

Estimating home fire severity with statistical distributions (통계적 분포를 통한 주택 화재 심도 추정)

  • Yunjung Park;Inha Song;Soyoun Lee;Kwang Hyun Nam;Rosy Oh;Jaeyoun Ahn
    • The Korean Journal of Applied Statistics
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    • v.36 no.6
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    • pp.591-618
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    • 2023
  • This paper evaluates the performance of various distribution assumptions in regression settings for estimating insurance loss. The gamma distribution is commonly used to handle the asymmetry property of loss distribution. However, recent studies highlight the significance of heavy-tailedness in loss distribution. Through an analysis of real home fire insurance data, we compare the effectiveness of different distribution assumptions in regression methods. Our findings show that the choice of parametric distributional assumption is crucial in determining premiums for various insurance products, including "excess of loss insurance" and "limit insurance". Additionally, we discuss practical considerations for applying our results in home fire insurance.