• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.4
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• pp.641-648
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• 2023

Recently, the rapid growth of artificial intelligence among the 4th industrial revolution has progressed based on the performance improvement of semiconductor, and circuit integration. According to transistors, which help operation of internal electronic devices and equipment that have been progressed to be more complicated and miniaturized, the control of heat generation and improvement of heat dissipation efficiency have emerged as new performance indicators. The DUT(Device Under Test) Shell is equipment which detects malfunction transistor by evaluating the durability of transistor through heat dissipation in a state where the power is cut off at an arbitrary heating point applying the rating current to inspect the transistor. Since the DUT shell can test more transistor at the same time according to the heat dissipation structure inside the equipment, the heat dissipation efficiency has a direct relationship with the malfunction transistor detection efficiency. Thus, in this paper, we propose various method for PCB configuration structure to optimize heat dissipation of DUT shell and we also propose various transformation and thermal analysis of optimal DUT shell using computational fluid dynamics.

• Journal of Korea Trade
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• v.27 no.3
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• pp.147-160
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• 2023

Purpose - This paper aims to investigate the competitiveness and complementarity of the agricultural products trade between Korea and Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) countries. The study evaluates the opportunities and challenges that Korea's agricultural sector faces after joining the CPTPP, and suggests strategies to deepen cooperation and expand Korea's agricultural products trade. Design/methodology - To achieve these objectives, we analyze the trade competition and cooperation relationship between Korea and CPTPP countries in the agricultural products trade. This study uses data from Chapters HS1-24 in UN Comtrade from 2012 to 2022, and applies the indices of revealed comparative advantage, export similarity, and trade complementarity to examine the trade dynamics. Furthermore, we use an Autoregressive Integrated Moving Average (ARIMA) model to predict the agricultural products trade complementarity index between Korea and CPTPP countries from 2022 to 2031. Findings - The findings of our analysis reveal that Korea's agricultural products trade competitiveness is weak compared to that of CPTPP countries, and Korea's agricultural products are at a competitive disadvantage. On the whole, the similarity index of agricultural products trade exports between Korea and CPTPP countries is low, the structure of agricultural products export is quite different, and trade competition is relatively moderate. The trade complementarity index between Korea and CPTPP countries is generally high, with strong complementarity and a large space for cooperation and development. The ARIMA model shows that in the next ten years, although the agricultural products trade complementarity index fluctuates, but is generally high, there will still be a complementarity advantage in the future. Originality/value - This study is the first attempt to investigate the competitiveness and complementarity of the agricultural products trade between Korea and CPTPP countries. We also introduce an ARIMA model to forecast and analyze the future agricultural products trade complementarity index. Our study provides new perspectives and solutions for the future development of Korea's agricultural products trade after joining the CPTPP.

• Structural Engineering and Mechanics
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• v.87 no.6
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• pp.529-540
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• 2023

A novel laminated-hybrid-composite-beam (LHCB) of glass-epoxy infused with flyash and graphene is constructed for this study. The conventional mixture-rule and constitutive-relationship are modified to incorporate filler and lamina orientation. Eringen's non-local-theory is used to include the filler effect. Hamilton's principle based on fifth-order-layer-wise-shear-deformation-theory is applied to formulate the equation of motion. The analogous shear-spring-models for LHCB with multiple-cracks are employed in finite-element-analysis (FEA). Modal-experimentations are conducted (B&K-analyser) and the findings are compared with theoretical and FEA results. In terms of dimensionless relative-natural-frequencies (RNF), the dynamic-response in cantilevered support is investigated for various relative-crack-severities (RCSs) and relative-crack-positions (RCPs). The increase of RCS increases local-flexibility in LHCB thus reductions in RNFs are observed. RCP is found to play an important role, cracks present near the end-support cause an abrupt drop in RNFs. Further, multiple cracks are observed to enhance the nonlinearity of LHCB strength. Introduction of the first to third crack in an intact LHCB results drop of RNFs by 8%, 10%, and 11.5% correspondingly. Also, it is demonstrated that the RNF varies because of the lamina-orientation, and filler addition. For 0° lamina-orientation the RNF is maximum. Similarly, it is studied that the addition of graphene reduces weight and increases the stiffness of LHCB in contrast to the addition of flyash. Additionally, the response of LHCB to moving mass is accessed by appropriately modifying the numerical programs, and it is noted that the successive introduction of the first to ninth crack results in an approximately 40% to 120% increase in the dynamic-amplitude-ratio.

• International Journal of Computer Science & Network Security
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• v.22 no.1
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• pp.69-76
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• 2022

At the current stage of globalization and European integration of Ukraine, the aspects related to the effective fight against corruption in the system of economic security of our country are receiving more and more attention, as they become a prerequisite for continuing reforms based on international funding. In order to consider this issue and solve this problem, the necessary step is to develop and implement real mechanisms of the system for detecting and preventing corrupt behavior, which are based on international anti-corruption standards. The leading component of this system is the management of corruption risks in the system of economic security in order to identify them and implement measures to reduce them. This study analyzes the corruption perception index in Ukraine in recent years, which showed a positive, albeit somewhat slow dynamics of its growth, indicating a gradual increase in overcoming corruption through the introduction of a number of anti-corruption measures and changes. It is proved that the current stage of socio-economic development of the country contributes to strengthening the processes of combating corruption and preventing corruption risks, creating an effective and efficient anti-corruption system of the state. The concept of "corruption" was studied, it was found that in the field of public administration it is considered from different positions and is closely related to the concept of "corruption risks". The essence and features of corruption risks are studied, the preconditions of their occurrence are formulated, the relationship between the causes of corruption risks and economic security in the field of public authority has been established. The system of corruption risk management is considered and its components are characterized. It is proposed to increase the effectiveness of anticorruption policy through the implementation of measures aimed at investigating the causes of corruption risks, as well as developed effective and effective means of reducing corruption risks within the system of economic security

• Korean Journal of Social Welfare Studies
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• v.42 no.4
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• pp.365-388
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• 2011

By analyzing 1998~2008 Korean Labor and Income Panel Study(KLIPS), this study examines socio-economic characteristics of people who become poor. The study also explores the reason why they are in the state of poverty. To find determinants affecting poverty entrance, discrete-time hazard models are applied. Major findings are as follows. The socio-economic characteristics driving people into poverty are in the middle way of the long-term poor and the non-poor, combining the characteristics of both groups. This implies that many cases of the newly poor tend to enter and exit from poverty repeatedly. Poverty entry rate was at a high level right after the economic crises, then was a downturn and remained fairly stable since 2000. However, the young, the high-educated, and even the professional are on the rise as a new poverty group. The major reason people become poor is temporary job loss. This factor is confirmed again by multi-variate analyses. In building anti-poverty policies, it is important to distinguish the long-term poor from the short-term poor. For the long-term poor, virtually the only affective policy will be income support. On the other hand, a labor-market strategy for jos security will be more effective for the short-term poor. The characteristics and determinants of poverty entry may affect poverty duration and exit in the future. Future research will be needed to investigate the relationship among these factors.

• The Plant Pathology Journal
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• v.39 no.6
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• pp.548-565
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• 2023

Armillaria root disease affects forests around the world. It occurs in many habitats and causes losses in the infested stands. Weather conditions are important factors for growth and development of Armillaria species. Yet, the relation between occurrence of damage caused by Armillaria disease and weather variables are still poorly understood. Thus, we used generalized linear mixed models to determine the relationship between weather conditions of current and previous year (temperature, precipitation and their deviation from long-term averages, air humidity and soil temperature) and the incidence of Armillaria-induced damage in young (up to 20 years old) and older (over 20 years old) coniferous stands in selected forest districts across Poland. We used unique data, gathered over the course of 23 years (1987-2009) on tree damage incidence from Armillaria root disease and meteorological parameters from the 24-year period (1986-2009) to reflect the dynamics of damage occurrence and weather conditions. Weather parameters were better predictors of damage caused by Armillaria disease in younger stands than in older ones. The strongest predictor was soil temperature, especially that of the previous year growing season and the current year spring. We found that temperature and precipitation of different seasons in previous year had more pronounced effect on the young stand area affected by Armillaria. Each stand's age class was characterized by a different set of meteorological parameters that explained the area of disease occurrence. Moreover, forest district was included in all models and thus, was an important variable in explaining the stand area affected by Armillaria.

• Journal of the Korea Institute of Building Construction
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• v.23 no.5
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• pp.639-650
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• 2023

In this research endeavor, we engaged with 70 construction safety specialists from established construction firms through surveys and interviews. The primary aim was to dissect and understand the weight and ramifications of specific cost items within the Occupational Safety and Health Management Funds(OSHMF) and Safety Management Expenses(SME). From our analysis, salient insights emerged. Within the realm of OSHMF, the cost items associated with safety facilities and the remunerations of safety managers were identified as paramount. It was observed that there are marked variations in the perceived significance and repercussions associated with diverse cost items of OSHMF. In stark contrast, when assessing the SME, the nuances in perceived weight and consequences of individual cost items were relatively muted, suggesting a more uniform viewpoint among the experts. Furthermore, our research probed the interrelationship between the significance and repercussions within OSHMF and SME domains. Notably, OSHMF manifested a positive linear relationship, suggesting that cost items of higher importance invariably had a more pronounced effect. On the other hand, the SME showcased a more subtle association, hinting at intricate underlying dynamics. The outcomes of this investigation are poised to offer instrumental guidance for enhancing safety protocols and diminishing accident occurrences in domestic construction undertakings.

• Journal of Aerospace System Engineering
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• v.18 no.2
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• pp.1-11
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• 2024

This paper applies a relative impact angle control guidance law to a communication-based multi-missile network system with uncertainties and disturbances. The multi-missile network system is represented as a transitive reduction directed acyclic graph. Furthermore, this paper introduces both centralized and decentralized guidance laws based on the graph's structure. The relationship between these guidance laws is analyzed by comparing them based on the communication structure and the presence of system noise. To analyze the effects of decentralized optimal cooperative guidance law, this paper assumes uncertainty in missile dynamics and predicted impact point information for the relative impact angle control mission. Monte Carlo simulations are conducted for various mission environments to analyze the impact of communication and its structure on the system.

• Korea Journal of Hospital Management
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• v.28 no.4
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• pp.62-72
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• 2023

Based on the basic ideology of health care, this study realized the seriousness of annual unmet medical need and conducted a study to confirm the relationship between the subjective perception of regional healthcare environment and unmet medical needs. The independent variable was classified into attitude 'satisfaction' and 'unsatisfaction' toward regional healthcare, and the dependent variable was classified as whether unmet medical needs occurred annually. Based on previous studies, the control variables were selected as demographic and socioeconomic characteristics that can affect the occurrence of unmet medical care annually and characteristics related to health behavior. Descriptive statistics were conducted for each variable on the extracted sample, and multivariate survey logistic regression analysis was conducted to confirm the association between variables. As a result, more unmet medical needs occurred annually than those who were satisfied with the medical services in the area where they lived. In addition, more unmet medical need occurred annually in "unsatisfied" households compared to households "satisfied" with local medical services. In residential areas, women live in "metropolis" and "rural areas" compared to "urban," women live in men, lower education levels, and poor subjective health levels, and less satisfied with local medical services. As such, the impact of environmental factors in the community on the use of health and medical services is one of the major areas of interest in the field of health science, such as health policy and social dynamics. Therefore, hospitals in each region need to make efforts in terms of hospital management to increase the overall satisfaction of medical services in the region by continuously monitoring the attitude of residents to achieve universal health security, and policymakers should also be interested and propose new policies.

• Journal of the Korean Regional Science Association
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• v.40 no.2
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• pp.21-38
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• 2024

Understanding the interrelationship between regional population dynamics and cultivated land is crucial for promoting regional economic vitality and enhancing food security. While prior research often addressed population migration and changes in crop area separately, this study employs a Panel Vector Auto Regression Model to examine the dynamic interaction between regional population shifts, changes in crop area, and the influx of foreign workers in agriculture. The results reveal a reciprocal relationship between population influx and crop area, indicating a negative impact on each other. Moreover, the analysis demonstrates that an expansion in crop area, particularly in field cultivation, significantly correlates with an increase in foreign workers. These findings underscore the mutual influence of labor shortages and diminished land availability in agriculture, with the influx of foreign workers potentially offering a positive impact on addressing structural challenges in rural areas.