• The Journal of Korean Physical Therapy
• /
• v.28 no.1
• /
• pp.8-13
• /
• 2016

Purpose: The purpose of the present current study was to examine control of upper limb multi-joint movements with differential coordination stability. To achieve the goals of the study, torque analyses were utilized to answer questions about how torque components were differed among various elbow-wrist coordination patterns. Methods: Eight self-reported right-handed college students (3 males and 5 females, mean age=20.6 yr) were volunteered. The task required participants to rhythmically coordinate the flexion-extension motions of their elbow and wrist with coordination relationship of $0^{\circ}$, $90^{\circ}$, and $180^{\circ}$relative phases between the two joints. Mean relative phase and phase stability (standard deviation of relative phase) were computed to for analysisze of overall coordination performance. To determine the figure out characteristics of torque components in elbow and wrist joints, impulse values of muscle torque (MT) and interactive torque (IT) and MT as a percentage of cycle duration (MT-PCD) were analyzed. Results: Torque results showed that the proximal elbow joint generated motions with mainly muscle efforts regardless of coordination patterns, while the distal wrist joint adjusted the coordination patterns by changing amount of MT. Impulse analyses showed that the least stable $90^{\circ}$ pattern was performed by utilizing a similar coordination strategy of the most stable $0^{\circ}$ pattern. Conclusion: The present current study suggests that the roles of distal and proximal joints differ in order to achieve various multi-joint coordination movements. This study provides information for use in gives an idea to development of rehabilitation or training programs for to persons with an impaired upper limb motor ability.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.3
• /
• pp.792-812
• /
• 2022

Multi-agent systems often need to achieve the goal of learning more effectively for a task through coordination. Although the introduction of deep learning has addressed the state space problems, multi-agent learning remains infeasible because of the joint action spaces. Large-scale joint action spaces can be sparse according to implicit or explicit coordination structure, which can ensure reasonable coordination action through the coordination structure. In general, the multi-agent system is dynamic, which makes the relations among agents and the coordination structure are dynamic. Therefore, the explicit coordination structure can better represent the coordinative relationship among agents and achieve better coordination between agents. Inspired by the maximization of social group utility, we dynamically construct a factor graph as an explicit coordination structure to express the coordinative relationship according to the utility among agents and estimate the joint action values based on the local utility transfer among factor graphs. We present the application of such techniques in the scenario of multiple intelligent vehicle systems, where state space and action space are a problem and have too many interactions among agents. The results on the multiple intelligent vehicle systems demonstrate the efficiency and effectiveness of our proposed methods.

• Proceedings of the Korea Inteligent Information System Society Conference
• /
• 2003.05a
• /
• pp.264-273
• /
• 2003

인터넷의 발달로 전자 상거래는 오늘날 일상생활의 한 부분이 되었다. 그러나, 수많은 쇼핑몰들과 그 쇼핑몰들이 제공하는 다양한 제품들 속에서 소비자가 원하는 물건을 찾아내는 것은 점점 많은 시간과 노력이 필요하게 되었다. 본 논문에서는 멀티에이전트 시스템을 이용해 공급망(Supply Chain)에서 구매자의 요구에 부합하는 제품을 제공할 수 있는 생산자를 보다 쉽게 연결시켜주는 방법을 제안한다. 기존의 멀티 에이전트 기반 공급망에서 주로 사용되는 협동 전략인 Joint Intention Theory와 SharedPlan Theory, 이 논문에서 제안하는 신경망을 이용한 방법을 비교해, 신경망을 이용한 방법이 갖는 효율성을 알아보고, 신경망을 이용한 멀티에이전트 기반의 협등 모델을 제시하였다. 이 모델은 구매자가 제품을 선택할 때 사용하는 소비평가 기준의 가중치를 소비자로부터 받아들여 그 기준에 가장 부합하는 판매자를 신경망을 이용한 분류(classification)방법을 통해 찾아내고, 이렇게 선택된 생산자를 소비자에게 연결시켜준다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.2
• /
• pp.288-307
• /
• 2013

This paper formulates resource allocation for decode-and-forward (DF) relay assisted multi-cell orthogonal frequency division multiple (OFDM) networks as an optimization problem taking into account of inter-cell interference and users fairness. To maximize the transmit rate of system we propose a joint interference coordination, subcarrier and power allocation algorithm. To reduce the complexity, this semi-distributed algorithm divides the primal optimization into three sub-optimization problems, which transforms the mixed binary nonlinear programming problem (BNLP) into standard convex optimization problems. The first layer optimization problem is used to get the optimal subcarrier distribution index. The second is to solve the problem that how to allocate power optimally in a certain subcarrier distribution order. Based on the concept of equivalent channel gain (ECG) we transform the max-min function into standard closed expression. Subsequently, with the aid of dual decomposition, water-filling theorem and iterative power allocation algorithm the optimal solution of the original problem can be got with acceptable complexity. The third sub-problem considers dynamic co-channel interference caused by adjacent cells and redistributes resources to achieve the goal of maximizing system throughput. Finally, simulation results are provided to corroborate the proposed algorithm.

• Korean Journal of Applied Biomechanics
• /
• v.26 no.1
• /
• pp.39-50
• /
• 2016

Objective: The purposes of this study were to compare the kinematics of a two-arm kettlebell swing between experts and beginners and to identify the correct postures and biomechanical key points in an attempt to prevent sports injuries induced by a kettlebell swing. Methods: Four experts (height, $169.7{\pm}1.5cm$; weight, $70.5{\pm}1.8kg$; age, $32.0{\pm}1.0years$) licensed to teach kettlebell exercises and three beginners (height, $173.7{\pm}4.1cm$; weight, $78.3{\pm}3.8kg$; age, $30.0{\pm}1.4years$) with no kettlebell exercise experience participated in this study. Each participant performed 15 repetitions of a two-arm kettlebell swing using a 16-kg weight. Joint angles, angular velocities, and peak angular velocity sequences were calculated and compared between the two groups. Results: Large ranges of motion (ROM) of the pelvic angle and hip joints were detected in the experts, while beginners showed greater ROM of the shoulder joint. Peak angular velocity magnitudes and sequences were significantly different between the two groups. Experts lifted the kettlebell upward using the hip joints, pelvis, and shoulder joints (proximal to distal order) sequentially and lowered it using the reverse order of peak angular velocities from the shoulder to hip joints. Conclusion: Mobility of the pelvic segment and hip joint are required, while stability of the other joints is needed to produce appropriate two-arm kettlebell swings. The activation and coordination of the gluteal and hamstring muscles are key points in kettlebell exercises.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37A no.12
• /
• pp.1133-1139
• /
• 2012

In this paper, hybrid mode beamforming (HMB) which allows simultaneous transmission of joint beamforming and disjoint beamforming is proposed. HMB is proven to be asymptotically optimal beamforming for sum rate growth. Extensive simulations show that HMB achieves nearly the same performance as joint encoding (JE) in symmetric interference channel. It is also shown that it outperforms JE in a more realistic asymmetric interference channel environment, though it still experiences some performance degradation due to power inefficiency of joint beamforming in asymmetric channel.

• Health Policy and Management
• /
• v.34 no.2
• /
• pp.106-119
• /
• 2024

Drug shortage is a persistent phenomenon that poses a public health risk worldwide and occurs due to a range of causes. The purpose of this study is to review key policies to prepare for and respond to drug shortages in selected countries, such as the United States, Canada, and some European countries in order to draw implications. This study reviewed the reports and articles derived from search engines and Google Scholar by using keywords such as drug shortage and stock-out. Over the last decade or so, the United States have strengthened requirements on advance notification for disruption and interruption of drug manufacturing, established the Inter-agency Drug Shortages Task Force to promote the communication and coordination of responses, and expedited drug regulatory processes. Similarly, Canada established the Multi-Stakeholder Steering Committee on drug shortages by involving representatives from central and local governments and private sectors. Canada also adopted a tiered approach to the communication of drug shortages based on the assessment of the severity of the shortage problem and released a detailed information guide on communication. In 2019, the joint task force between the European Medicines Agency and the Heads of Medicines Agencies issued guidelines on drug shortage communication in the European Economic Area. The countries reviewed in this paper focus on communication across different stakeholders for the monitoring of and timely response to drug shortages. The efforts to protect public health from the negative impact of the drug shortage crisis would require multi-sectorial and multi-governmental coordination and development of guidelines.

• Journal of the Korean Academy of Clinical Electrophysiology
• /
• v.5 no.2
• /
• pp.35-45
• /
• 2007

The purpose of this study was to examine spiral way movement of a trunk exerts on the movement ability. The details established to achieve for this article. This examination confirmed the weight, weight/height2 index, ratio of lumbar to pelvic, musculoskeletal quantity, push up for 2 minute, pitch a ball and voluntary isometric contraction with flexion and extension of knee joint of the subjects with spiral direct movement. Healthy eighteen subjects who understand fully the significance of procedure, consented to a plan, without neuromuscular disease were participated in two groups of experiment. The group were a spiral movement(9), rectilinear movement(9). Trunk movement tested 2 sessions of a spiral movement and rectilinear movement with a push up for 2 minute, 5days per a week, for the 4 weeks. This experiment tested 3 times with a sufficient rest for fatigue limitation. An analysis of the results used a paired samples t-test for difference from before and after experiment. The following results were obtained; At an internal change of the body, the musculoskeletal quantity was increased significantly to spiral movement group, but the weight was increased significantly, the musculoskeletal quantity was not significant to rectilinear movement. The movement ability evaluation for a external change was increased significantly in a push up for 2 minute, pitch a ball, isometric contraction with extension of knee joint of a spiral movement group, but a push up for 2 minute was increased significantly in a push up for 2 minute on the abdominal muscle training of a rectilinear movement group. As compared with a rectilinear movement, a spiral movement was more effect by cooperation with nerve and musculoskeletal system and an increase in movement ability was caused by learning acknowledgment, muscular reeducation. These results lead us to the conclusion that a spiral movement of trunk was more effect than a rectilinear movement, the coordination of nerve and musculoskeletal system was of importance of Multi-direction movement. Therefore, A further studies concerning the therapeutic exercise intervention and active-dynamic analysis could enhance the development of the most effect on the trunk.

• Journal of Korea Technology Innovation Society
• /
• v.13 no.1
• /
• pp.68-98
• /
• 2010

This study was conducted to analyze the results of the implementation of next-generation growth engine program that was promoted across all government agencies for five years from 2004 as part of a range of initiatives aimed at expanding the nation's economic growth potential. The results were analyzed in this study using five indices: program purpose and design; strategic planning; program management; program results; and pan-governmental agency cooperation and coordination. The results of the study include the following. First, regarding program purpose and design, it was found that consistent leadership in the promotion of the programs was insufficient as the relevant program promotion systems and financial resources were dispersed among governmental agencies, even though the objectives and validity of the programs were recognized. Second, with regard to strategic planning, it was found that although the program objectives and technical development strategy had been established at the beginning of the program, they were biased toward the technical objectives and mainly implemented by the technology suppliers. Third, regarding program management, it was found that the responsibility for general administration, ranging from task planning to policy improvement, was given to the appointed program director but that the system of cooperation among the agencies was insufficient to carry out the relevant tasks. Fourth, regarding the results of the program, it was difficult to understand the results consistently as the economic objectives were not clearly presented, even though the technical objectives were achieved despite the short implementation period of the program. Fifth, with regard to pan-governmental agency cooperation and coordination, it was found that the coordination organization whose remit was to implement the program was established pursuant to the Basic Law on Science and Technology, but that no detailed regulations or guidelines on the operation of the organization were drawn up. To efficiently plan and execute future pan-governmental agency R&D programs that are similar to the next-generation new growth engine program, various requirements should be met, namely, 1) joint planning and consistent program design among governmental agencies, 2) clarification of the program objectives and budget allocation system, 3) establishment of a pan-governmental agency program operation and assessment system, 4) formulation of a strategy for linking R&D with standardization, and 5) enactment of pan-governmental agency joint operation rules.

• Ocean and Polar Research
• /
• v.23 no.4
• /
• pp.425-431
• /
• 2001

From an ecological point of view, the western part of the Atlantic sector is one of the most productive areas in the Southern Ocean. Antarctic krill (Euphausia superba) and krill-dependent predators such as fish, seals, and birds are abundant there, and most krill fisheries have operated in this area since 1970s. The hottest issues for the proper management of krill resources nowadays are to determine total biomass in this area, and to identify environmental forces controlling stock fluctuation. This paper reviews and collates information on ongoing oceanographic activities in the Antarctic Peninsula region concerning these issues. To delineate the status and function of Antarctic krill population in Antarctic marine ecosystems, multinational researches along the Antarctic Peninsula area have been developing recently. Four member states of CCAMLR (Japan, Russia, UK, and USA) had conducted acoustic surveys in January-February 2000 (socalled CCAMLR-2000 survey), and krill standing stock at 120 kHz was estimated to be 44.29 million metric tonnes in the western Atlantic sector of the Southern Ocean. On the other hand, the Southern Ocean GLOBEC (SO-GLOBEC) Programme has prepared a serial winter survey to examine the factors that govern krill survivorship and distribution in relation to shelf circulation processes. Ship-based surveys using ice-breakers are being conducted by three nations (Germany, UK, and USA) around the Marguerite Bay during the austral fall and winter 2001 and 2002. In addition to these two large-scale surveys, some CCAMLR members have carried out joint oceanographic surveys near the South Shetland Islands to detect ecosystem changes since 1994. Especially from December 1999 to February 2000, in conjunction with CCAMLR-2000 survey, four nations (Japan, Korea, Peru, and USA) conducted acoustic surveys to produce time-series information on krill distribution and biomass near the South Shetland areas. Though the aims of each program and the approach to solve the scientific questions were different each other, the results from each program fill the gaps between programs. Further cooperation and exchange in these activities could be beneficial to each program.