Earticle

본 연구는 12주간의 태권도 수련프로그램 참여한 노인의 신체 구성과 기초체력에 관한 연구를 진행하였다. 대상자는 K지역 D시에 거주하는 65세 이상 노인 20 명에게 1주일 동안 3회에 걸쳐 60분씩 12주간 수련프로그램에 참여하도록 하였으며, 대상자들의 운동 전과 운동 후를 비교하였다. 분석은 SPSS 통계프로그램을 활용하여 Paired t-test를 진행하였다. 분석 결과는 다음과 같다. 첫째, 12주간 태권도 수련프로그램을 신체 구성에서 적용하였을 때, 제지방률이 낮아진 것을 확인 할 수 있었다. 둘째, 12주간 태권도 수련프로그램을 기초체력에 적용하여 진행했을 때, 긍정적인 효과가 나타났다. 셋째, 12주간 태권도 수련프로그램을 적용하여 평형성(눈 감고/눈 뜨고 외발 서기) 측정에서도 통계적으로 유의미한 결과를 얻었다. 결과적으로 12주간의 태권도 수련프로그램을 노인들에게 적용하는 경우, 노인들의 신체구성은 물론 기초 체력을 강화시킬 뿐 아니라 평형성에도 긍정적인 효과 가 있다는 것을 알 수 있다. 아마도 태권도 프로그램에 참여함으로써 신체리듬이 달라지면서 일상생활의 활력을 가져온 것으로 설명될 수 있다. 반면, 도시지역의 노인들만을 대상으로 연구가 진행되었기 때문에 표본의 일반화에 한계가 있었다.

The purpose of this study is to find out the effects of participating in a 12-week taekwondo training program on the physical composition and basic fitness of the elderly. The subjects of this study were 20 senior citizens aged 65 or older living in D, K-region. The exercise program was conducted for 60 minutes at the frequency of 3 times a week for 12 weeks with 10 minutes of warm-up, 40 minutes of main exercise and 10 minutes of finishing exercise in compliance with the recommended amount of exercise presented in the ACSM. The analysis before and after exercise was conducted using SPSS 18.0. The conclusions from this study through the above procedures and methods are as follows. First, after 12 weeks of taekwondo training program, the body composition showed that the fat rate had improved. Second, after the application of the 12-week taekwondo training program, I could see that there were significant results in basic physical strength. Third, after 12 weeks of taekwondo training program, it was found that there were significant results in equilibrium (eyes and unicycle). In summing up the above partial results, it can be concluded that the 12-week taekwondo training program has had some positive effects on body composition, basic physical strength and equilibrium. However, it is considered desirable to conduct additional research on senior citizens in farming and fishing villages in the future because it is difficult to generalize the data since it is targeted at senior citizens in urban areas.

The purpose of this study was to compare the performance of postural control between outstanding skiers and ordinary skiers. All subjects were assigned to 2 groups (outstanding group – national skier (n=13), candidate of national skier, and ordinary group – college level skier (n=13)). Dynamic posturography was measured for Equilibrium score (stage 1 to 6), sensory tests (somatosensory ratio (SOM), visual ratio (VIS), and vestibular ratio (VEST), and reaction time testing. In results, equilibrium scores of stage 1 and 4 in the outstanding group were significantly greater than the ordinary group. In addition, equilibrium scores of stage 3, 5 and 6 in the outstanding group were higher than the ordinary group. In the sensory tests, both groups mostly utilized SOM when they performed postural control. Moreover, VIS in the outstanding group was greater than the ordinary group; however, there was no difference in reaction time between groups. In conclusion, postural control in the outstanding was higher than the ordinary group, thus training for development of equilibrium is required to improve ski performance.

The purpose of this study was to investigate the balance abilities of the adolescent girl with brain lesions by STS (Sit-to-Stand) action analysis before and after the rehabilitative horse riding of 16 week program. The subject aged 16 year old who had the disabilities of spasticity and hemiplegia was recruited with the consent approval. The equilibrium abilities of the subject were tested by Sit-to-Stand examination with WTT (Weight Transfer Time), MRI (Mean Rising Index), MWA (Mean Weight Asymmetry), MTFV (Max Trunk Flexion Velocity), and MTEV (Max Trunk Extension Velocity). Research was designed by AB single subject study with baseline of 3 times of measurement and rehabilitative horse riding treatments. In the results, the enhancement of the subject’s equilibrium ability was shown by the comparison between baseline and treatment by the STS test that WTT was 2.37 sec faster, MRI was 6.64N/kg higher and MWA was 8.12% lower and MTFV was 0.57/sec lager than all those means of baseline. It suggested that the subjects showed her enhanced balance ability while in sitting and standing action test after the rehabilitative horse riding treatments.

정보화 시대는 사회 구성원의 다양한 욕구가 충분히 실현되는 사회이다. 디지털 시대는 아날로그 방식이 가졌던 시간적․공간적 제약을 극복할 수 있기 때문에 개개인의 욕구를 최대한 실현시킬 수 있는 것이다. 그러나 이러한 장점의 뒷면에는 익명성에 따르는 구성원들의 건정한 윤리의식이 무엇보다도 중요한 것으로 떠오르고 있다. 구성원들의 윤리의식을 제고하기 위한 방안에는 여러 가지 접근이 있을 수 있겠지만 여기서는 구성원들의 합리적인 사고를 제고함으로서 감감적인 시대에 보완책을 마련해보고자 하는 의도가 있었다. 이를 위해 기존 콜버그의 인지구조적 접근에 따른 토론식 방법을 그 해결책의 하나로 제시하고 있다. 토론을 통해 새로운 인지자극에 노출되고 인지구조적 불균형을 발생케 하여 새롭게 균형잡아 가는 과정에서 인지구조의 질적도약을 도모해 내 정보에 대한 합리적인 접근을 시도해 보고 있다.

In this paper, I tried to develop the model for discussive class in digital society. For this purpose, this paper studied the Kohlberg's cognitive moral development theory. I enterpreted the theory as the formalism which resulted from his refuting relativism. Kohlberg takes the relativists as one of his two major apponents. The other is the authoritarians in moral education. And I enterpreted the theory as human activism. In according to the Kohlberg's theory, the basic mental structure is the result of interaction between certain organismic structuring tendencies and the outside world. The other aim of this paper is explain the development of cognitive structures by appealing to a fundamental process of equilibration which is the essential idea of system science. Here equilibration refers to the process that leads from a state near equilibration to a qualitatively different state at equilbrium by way of mulitiple disequlibria and reequilibrations. In this process, I stressed on the discussive method for overcoming the given cognitive structure.

Solvent extraction experiments of Mn(II) by Cyanex 301 has been done from chloride solutions. The effect of variables, such as the initial pH and the concentration of Mn and extractant, on the extraction of Mn was investigated. The solvent extraction reaction was identified by applying a slope analysis method to the extraction data. In order to estimate the equilibrium constant for this solvent extraction reaction, the activity coefficients of aqueous species as well as the complex formation reactions between Mn and chloride ion were considered. Bromley equation was employed to calculate the activity coefficients. It was possible to predict the distribution coefficients of Mn from initial extraction data by employing the equilibrium constant. There was a good agreement between the experimentally measured distribution coefficients of Mn(II) and those predicted in this study.

This study was performed on 26 disabled adolescent participants(16 male, 10 female) with the objective of testing changes in equilibrium after engagement in horseback riding. Participants of total 26 persons were divided into three groups as follows: 6 children with Cerebral Palsy(CP), 14 children with Intellectual Disability(ID) and 6 children with Autism(AT). Participants engaged in therapeutic horseback riding(TR) two times per week for 30 minutes per session. The 26 participants demonstrated a considerable increase in equilibrium ability, with an average increase in equilibrium time of 44.22±50.70 sec after TR. Equilibrium also increased according to disability group: CP(P<0.05), ID(P<0.001), and AT(P<0.05). TR should be considered as a possible method for improving functionality in the physically disabled. This data may also be usefully applied to the development of a horseback riding program for the improvement of equilibrium in the disabled.

Modern network security has a great difficulty in cyber attack detection. In this context, this work presents an CNN-LSTM-GRU Model for cyber attack detection. AEO was used to maximize feature selection for the model, therefore lowering unnecessary data while maintaining important attack patterns. With 98% accuracy, the suggested model beats conventional GRU, LSTM, and RNN architectures according to experimental data. Computationally efficient for the proposed model achieves equivalent accuracy to the Transformer model with less number of FLOPs and parameters.

에너지원으로서 천연가스의 비중이 점차적으로 증가하고 있으며 천연가스의 경우 전체 에너지 소비량 대비 15% 이상 을 소비할 만큼 중요한 에너지원의 역할을 가지고 있다. LNG의 경우, 천연가스의 청정성, 편리성 및 경제성이라는 장점 으로 인하여 수요가 늘어나고 있으며 또한 LNG 연료추진선박, LNG 자동차 및 버스의 공급을 위한 소형 LNG 저장설비 의 수요가 급증하고 있다. 본 연구에서는 소형 LNG 저장설비에서 가장 큰 사고로 이를 수 있는 Rollover에 대하여 초저 온 유체 계면에서의 Vapor-Liquid Equilibrium을 이용하여 해석을 수행하였다. 해석된 결과를 이용하여 소형 LNG 저장 설비에서의 누출 피해예측 및 분석을 통한 사고영향평가를 수행하여 추후 건설 예정 중인 설비에 대한 안전성을 검토하 고자 한다.

The share of natural gas as an energy source is gradually increasing, and natural gas has an important role as major energy source role that consumes more than 15% of the total energy consumption. In case of LNG, there is an increasing demand due to the advantage of cleanliness, convenience and economy of natural gas and also, demand for the small LNG storage facilities for fuel supplying LNG fuelled vessels, LNG cars and buses is increasing rapidly. In this study, we analyze the rollover case, which is the biggest LNG leakage accident in small LNG storage facility, by using Vapor- Liquid Equilibrium at the cryogenic fluid interface. Using this calculated results, we evaluate the accident impact by prediction and analysis of leakage damage in small LNG storage facility and examine the safety assessment for facilities to be constructed in the future.

In this paper, we investigate the application of Nash equilibrium strategy to enhance coordination and decision-making in multi-agent systems, specifically focusing on Automated Guided Vehicles (AGVs) systems. Traditional reinforcement learning methods often face challenges in multiagent environments due to the non-stationarity introduced by multiple learning agents and the complexity of coordinating actions among them. To address these challenges, we propose an approach that integrates game-theoretic principles of Nash equilibrium into existing multi-agent reinforcement learning frameworks. By incorporating Nash equilibrium considerations into the policy update mechanisms, agents can anticipate and respond to the strategies of other agents proactively. This integration reduces conflicts and improves cooperation without relying solely on reward shaping or penalization for undesirable behaviors, such as collisions. Additionally, we introduce a collaboration cost into the reward function to further incentivize cooperative behavior among agents. We validate the effectiveness of our approach in a flexible manufacturing system simulated using PyBullet, utilizing the default URDF models to create a realistic and standardized environment. Multiple AGVs operate as autonomous agents tasked with collaboratively optimizing production tasks. Experimental results demonstrate that our Nash equilibrium-based method significantly outperforms traditional algorithms—including MADDPG, NDQN, CQL, COMA, IQL, PPO, SAC, and DQN—in terms of cumulative reward, policy convergence speed, and overall system throughput.

We present a general equilibrium model of a moral-hazard economy with many rms and nancial markets, where stocks and bonds are traded. Contrary to the principal-agent literature, we argue that optimal contracting in an innite economy is not about a tradeo between risk sharing and incentives, but it is all about incentives. Even when the economy is nite, optimal contracts do not depend on principals' risk aversion, but on market prices of risks. We also show that optimal contracting does not require relative performance evaluation, that the rst best riskfree interest rate is lower than that of the rst best, and that the second-best equity premium can be either higher or lower than that of the rst best. Based on these results, we argue that given the volatility of the market portfolio, moral hazard can contribute to the resolution of the riskfree rate puzzle, but unlike the literature suggests, moral hazard can neither help explain nor deepen the equity premium puzzle.

The paper investigates the effects of ambiguity on asset prices when all traders face ambiguous information about the variance of the true value in the ex ante stage and they can observe the true value at some costs. To do this, we adopt the model of Grossman and Stiglitz (1980) and assume that uninformed traders face ambiguous information. It is found that traders who will purchase information about the true value consider the lowest variance of the true value as their worst case scenario in the ex ante stage. Meanwhile, traders who will remain uninformed consider the maximum variance of the true value as their worst case scenario both in the ex ante and interim stage. We also find that the value of information increases due to existence of ambiguous information.

The aim of this study is to compare the effect of stabilization and equi-librium training on hip muscle strength and balance performance of ka-rate athletes with deafness. Twenty-seven athletes from the National Deaf Karate Team (18 males, nine females) with an average age of 24.53±3.62 (18–43) years were included in this study. The athletes were randomly assigned to either stabilization or equilibrium training group. Both training programs lasted 6 weeks with once per day and 5 days per week sessions. The assessment of muscle strength and balance performance was done before and after the training. The muscle strength and balance have improved in both training groups (P<0.05), but while there was no difference in the results of muscle strength be-tween the groups (P>0.05), balance performance was better in the equilibrium training group (P<0.05). In conclusion, stabilization and equilibrium training have helped the karate athletes with deafness to improve their muscle strength and balance performance.

This paper provides the notion of ‘robust survival’ to examine the existence of equilibrium in a general equilibrium model with incomplete markets (GEI model). The GEI model satisfies robust survival if for each agent, any non-optimal choice is dominated by a choice that can be slightly shaken to be budget-feasible in the wake of slight price-endowment variations. The new survival condition differs from the GEI irreducibility of Gottardi and Hens (1996) in the ability to explain the presence of agents with the cheap initial endowments in equilibrium. Both survival conditions can be rather complementary in investigating the effect of financial innovation on the welfare of agents who lack the cheaper consumption property in the pre-innovation economy. We take an example where the economy satisfies the new survival condition and is not GEI irreducible because an agent has the cheap initial endowments. The economy becomes GEI irreducible when asset markets are completed through financial innovation. This means the agent with the cheap endowments in the pre-innovation economy gains access to cheaper consumptions in the post-innovation economy.

The fundamental theorem of asset pricing (FTAP) is built on the commonsense principle that asset pricing rules assign null cost to the null contingent income. The zero-incomezero- cost (ZIZC) principle is inherently fulfilled when arbitrage pricing rules are either linear or sublinear. This principle is also taken for granted in the literature which examines convex pricing rules as a viable form of valuation. It is illustrated, however, that the ZIZC principle does not hold in equilibrium of markets where progressive taxation leads to convex pricing rules. Thus, well-known notions of arbitrage provide limited explanatory power for asset pricing in the case where nonlinear net returns prevail due to market frictions. This paper presents a ‘right’ form of the FTAP based on a new notion of arbitrage which is characterized by the asymptotic behavior of marginal net returns. Remarkably, the new no-arbitrage condition leads to sublinear pricing rules under nonproportional net return schedules. Consequently, the result of the paper is a generalization of the FTAP of the literature to the case where return-related market frictions make the net return schedule nonlinear.

본 논문은 트럼프 행정부 2기의 전방위적 관세 인상 정책이 세계 경제에 미치는 영향을 분석 한다. 기존 선행연구가 부분균형 중력모형에 주로 의존한 것과 달리, 본 연구는 일반균형 구조 적 중력모형을 활용한 반사실적 분석을 통해 세계 경제의 상호의존성을 반영하여 미국의 관세 인상 정책이 주요국 경제에 미치는 파급효과를 분석한다. 분석 결과, 주요국의 무역과 생산이 전반적으로 위축되는 가운데, 특히 미국과 무역 의존도가 높은 캐나다와 멕시코가 부정적 영 향을 상대적으로 크게 받는 것으로 나타난다. 또한 주요국이 미국 이외의 대체 수출시장을 확 보하기 위한 경쟁이 심화되면서 수출시장 접근성이 악화되고 공장도 가격이 하락하는 반면, 수입국의 수입시장 접근성은 오히려 개선되는 것으로 나타난다. 한국도 미국의 관세 인상 정 책의 영향으로 무역이 위축되고 수출시장 접근성이 악화되는 것으로 분석된다. 이에 따라 대 체 수출시장 진입을 위한 정부의 적극적인 정책 지원과 기업의 전략적 대응이 필요하며, 상대 적으로 높은 관세율이 한국 경제에 미치는 부정적 영향을 완화하기 위해 미국의 한국에 대한 관세 인상을 억제하는 외교적 노력도 요구된다.

Purpose : This study investigates the comprehensive and simultaneous impacts of U.S. tariffs increases on the global economy. Research design, data, methodology : The paper constructs a structural gravity model by building a bilateral trade panel dataset for 72 countries using the ADB Multiregional Input-Output Table (MRIO). We derive the general equilibrium of the structural gravity model using the Poisson pseudo-maximum-likelihood(GEPPML) estimation method and conduct a counterfactual analysis of four scenarios based on U.S. tariff increases. Results : The results suggest that the decline in both trade and production is relatively larger in Canada and Mexico, while Korea and other major countries also experience decreases in both trade and production. Major countries' access to export markets deteriorates due to intensified competition for alternative export destinations substituting for the U.S. In addition, the negative effects on Korea become greater as the tariff on Korea is relatively higher and the U.S.-China conflict becomes more intense. Conclusions : The results indicate that the government support and strategic corporate responses in each country are necessary to mitigate the strain caused by intensified export competition. In addition, diplomatic efforts are also required to maintain relatively low tariff levels from the U.S. in order to reduce the negative effects of U.S. tariff increases.

본 논문은 교통망에서 관측 링크 교통량, 미관측 링크의 이용자평형 정보를 이용하여 O-D행렬을 수학적으로 생성하는 모형을 제시하고 있다. 교통량이 관측되지 않은 링크로부터 이용자 평형 상태에서 추출 가능한 정보를 바탕으로 일련의 논리적 연산을 거쳐 실제교통량에 근접하는 서브알고리듬을 유추하여 O-D행렬 추정의 정확도와 연산의 일관성을 제고하였다. 이를 위해 이용자평형상태에서 새로운 정리(Theorem)와 보조정리(Lemma)를 유도하여 적용하였다. 모형의 시험은 3개의 초기 O-D 행렬과 3개의 미관측 링크 교통량 시나리오를 각각의 모형에 적용하여 그 결과를 비교하였다. 적용 결과 본 논문에서 제시된 모형은 기존의 이용자균형 접근방식의 모형emf에 비해 추정된 O-D값의 실제 값과의 차이(O-D Trip RMSE)가 현저히 감소되는 것을 확인하였다.

This research addresses the problem of estimating Origin-Destination (O-D) trip matrices from link volume counts, a set of unobserved link volumes and information of user equilibrium flows in transportation networks. A heuristic algorithm for estimating unobserved link flows is derived, which provides volume estimates that are approximately consistent with both observed flows and an assumption of user equilibrium conditions. These estimated link volumes improve the constraints associated with the synthetic OD estimation model, providing improved solution search procedure. Model performance is tracked in terms of the root mean square errors (RMSE) in predicted travel demands, and where appropriate, predicted linked volumes. These results indicate that the new model substantially outperforms existing approaches to estimating user-equilibrium based synthetic O-D matrices.