• Title/Summary/Keyword: Load balance

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The Studies on the Foot Stability and Kinesiology by Direction of Carry a Load during Gait (보행 시 부하의 위치에 따른 발의 안정성 및 운동학적 분석에 관한 연구)

  • Lee, Sang-Yeol;Bae, Sung-Soo
    • The Journal of Korean Physical Therapy
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    • v.21 no.2
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    • pp.97-101
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    • 2009
  • Purpose: This study examined how the direction of carrying a load affects the foot stability and kinesiology while walking. Methods: The heel rotation, Hallux stiffness, foot balance, metatarsal load, toe out angle, subtalar joint flexibility were measured in 40 adults (men and women) who carried a load back and forth, walking on a 2-meter-long board. The measurement was carried out three times and the mean of the measurements was used to compare the difference between the front, back and the condition without a load. Results: While walking, heel rotation and hallux stiffness occurred most when a front load was applied compared to a back load or no load condition (p<0.05). A metatarsal load also appeared to be the highest with the frond load, but there was no significant difference in the balance of the whole foot. Both the toe out angle and subtalar joint flexibility appeared to increase significantly (p<0.05). Conclusion: Applying the front load causes subtalar joint instability and increases the plantar foot pressure imbalance during walking.

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The Study on the Field test and Operational Method of a Direct Load Control System for Air conditioner (에어컨부하 직접제어시스템 실증시험 및 운용방안에 관한 연구)

  • Gang, Won-Gu;Kim, Chung-Hwan;Kim, Myong-Soo
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2825-2827
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    • 2000
  • In electric power industry. load balance has been one of the most fundamental and important management goals. Therefore. the strategy to achieve high quality load management now includes load balance besides the stabilization of electricity supply and quality management of electricity. Amongst many techniques of load management. direct load management has been actively studied and utilized to increase power facility and peak load suppression. Higher peak load situation is appeared during summer than during winter in Korea. and approximately 20% of the peak load is due to the load for air-conditioning. To cope with this peak load problem during summer KEPCO is performing a research project to develop a system to remotely control air-conditioning load using wireless communication. Currently, applicable facilities are limited to small-scale air-conditioning facility that has less than 2KW power capacity. This paper described the 1st year of efforts made in the study.

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The Load Balancing Destage Algorithm of RAID5 Controller using Reference History (참조 정보를 이용한 RAID5 제어기의 부하 균형 반출 기법)

  • Jang, Yun-Seok;Kim, Bo-Yeon
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.3
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    • pp.776-787
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    • 2000
  • Write requests which stored in disk cache of the RAID5 controller should be destaged to disk arrays according to the destage algorithm. As the response performance of the parallel IO request is being hit by the effect of the destage, several destage algorithms have been studied to enhance the performance of he RAID5 controller. Among the destage algorithms, the load balancing destage algorithm has better performance than other destage algorithms when system load is highly increased. But the load balancing destage algorithm gives priority to load balance among the disks in disk arrays, therefore, when some disks are affected by the very heavy system load caused by small data requests, the load balancing destage algorithm cannot enhance the performance of parallel IO requests effectively since it makes effort to maintain the load balance without the benefit of the locality of the write requests. This paper proposes a new RAID5 controller that applied reference-load balancing destage algorithm which decides the destage priority based on the reference history and load distribution of the disks. The simulation results show that RAID5 controller with the reference-load balancing destage algorithm has better performance than previous load balancing destage algorithm.

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An Implementation of Balance Beam Controller(New Construction Machinery) for an Attitude Control and Stabilization of an Unstructured Object (공중물체의 자세제어 및 안정화를 위한 밸런스 빔 제어기(신건설장비) 구현)

  • Yi Keon Young;Kim Jin-Oh
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.1
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    • pp.38-44
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    • 2003
  • In this study, the balance beam control subsystem, new type of construction machinery using the mechanism of CMG (control moment gyro), for the attitude control of an unstructured object such as a beam carried by a tower crane, is designed and implemented. The balance beam controller consists of a wheel spinning at high speed and an outer gimbal for controlling the attitude of the wheel. Two motors, one for the wheel and the other for the gimbal, are used. Applying force to the spin axis of the wheel, as an input of the system, leads the torque about the axis because of the gyro effects. This torque is used to control the attitude of the unstructured object in this study. For the stabilizer function, in addition, holding the load at the current position, the attitude of the wheel is freed by cutting the power applied to the gimbal motor of the balance beam controller, which result in the braking force to stop the load by gyro effect. The works presented here include the mechanical system of the balance beam controller, the remote controller, the servo controller and the control software for the system. We also present experimental results to show that the system we proposed is useful as a new construction machinery which can control the attitude of the beam hanging from a tower crane.

Comparison of nutrient balance and nutrient loading index for cultivated land nutrient management (농경지 양분관리를 위한 양분수지 지표와 양분부하 지표간의 비교)

  • Lee, Jun-Hyung;Yoon, Young-Man
    • Korean Journal of Environmental Biology
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    • v.37 no.4
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    • pp.554-567
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    • 2019
  • Recently, concerns regarding the environmental impact due to nutrient input in croplands have increased. Therefore, the government is promoting the introduction of a nutrient management system in croplands to solve the problem of excessive nutrient input. This study was carried out to establish nutrient indicators in regional croplands to facilitate the introduction of the national nutrient management system in Korea. The nutrient load and balance indicators for nitrogen and phosphorus were analyzed for nine provinces (Gang-won, Gyeong-gi, Chung-buk, Chung-nam, Jeon-buk, Jeon-nam, Gyeong-buk, Gyeong-nam, and Jeju). In the correlation analysis between the nutrient load and nutrient balance, the correlation coefficient (r) for nitrogen was 0.2504, which was not statistically significant at the 5% significance level. However, the correlation coefficient for phosphorus was 0.7375, which was statistically significant at the 5% significance level. In the nutrient management index, phosphorus showed mutual compatibility between the nutrient load and the nutrient balance indicators, but nitrogen showed no mutual compatibility between the nutrient load and the nutrient balance indicators. Therefore, utilization of the nutrient balance indicator, reflecting the characteristics of the agricultural environment, was more reasonable as a nutrient management index for regional nutrient management.

Load Balancing Scheme for Heterogeneous Cellular Networks Using e-ICIC (eICIC 가 적용된 이종 셀룰러 망을 위한 부하 분산 기법)

  • Hong, Myung-Hoon;Park, Seung-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39A no.5
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    • pp.280-292
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    • 2014
  • Recently, heterogeneous networks consisting of small-cells on top of traditional macro-cellular network has attracted much attention, because traditional macro-cellular network is not suitable to support more demanding mobile data traffic due to its limitation of spatial reuse. However, due to the transmit power difference between macro- and small-cells, most users are associated with macro-cells rather than small-cells. To solve this problem, enhanced inter-cell interference coordination (eICIC) has been introduced. Particularly, in eICIC, the small-cell coverage is forcibly expanded to associate more users with small-cells. Then, to avoid cross-tier interference from macro-cells, these users are allowed to receive the data during almost blank subframe (ABS) in which macro-cells almost remain silent. However, this approach is not sufficient to balance the load between macro- and small-cells because it only expands the small-cell coverage. In this paper, we propose a load balance scheme improving proportional fairness for heterogeneous networks employing eICIC. In particular, the proposed scheme combines the greedy-based user association and the ABS rate determination in a recursive manner to perform the load balance.

Design of LTBC Controller for Tension Control in Down Coiler Process of Hot Strip Mills (열간압연 권취공정의 장력제어를 위한 LTBC 제어기 설계)

  • Lee, Sang Ho;Park, Hong Bae;Park, Cheol Jae
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.4
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    • pp.301-308
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    • 2015
  • In this paper, we propose an LTBC (Low Tension and Load Balance Control) scheme to improve a coiling shape control by reduction the tension fluctuation by the torque disturbance in the down coiler process of hot strip mills. The proposed controller is a combination of an LTC to control the overload at load-on in the mandrel and an LBC to regulate the load balance of the upper and bottom pinch roll. A tension calculation model is suggested with the concept of the tension deviation. The effectiveness of the proposed control scheme is verified from simulation under a disturbance of the pinch roll torque. Using a field test, we show that the performance of the shape and tension control is improved by the LTBC control.

A Parallel Loop Scheduling Algorithm on Multiprocessor System Environments (다중프로세서 시스템 환경에서 병렬 루프 스케쥴링 알고리즘)

  • 이영규;박두순
    • Journal of Korea Multimedia Society
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    • v.3 no.3
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    • pp.309-319
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    • 2000
  • The purpose of a parallel scheduling under a multiprocessor environment is to carry out the scheduling with the minimum synchronization overhead, and to perform load balance for a parallel application program. The processors calculate the chunk of iteration and are allocated to carry out the parallel iteration. At this time, it frequently accesses mutually exclusive global memory so that there are a lot of scheduling overhead and bottleneck imposed. And also, when the distribution of the parallel iteration in the allocated chunk to the processor is different, the different execution time of each chunk causes the load imbalance and badly affects the capability of the all scheduling. In the paper. we investigate the problems on the conventional algorithms in order to achieve the minimum scheduling overhead and load balance. we then present a new parallel loop scheduling algorithm, considering the locality of the data and processor affinity.

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Experimental and finite element studies of special-shape arch bridge for self-balance

  • Lu, Pengzhen;Zhao, Renda;Zhang, Junping
    • Structural Engineering and Mechanics
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    • v.35 no.1
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    • pp.37-52
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    • 2010
  • Special-shape arch bridge for self-balance (SBSSAB) in Zhongshan City is a kind of new fashioned spatial combined arch bridge composed of inclined steel arch ribs, curved steel box girder and inclined suspenders, and the mechanical behavior of the SBSSAB is particularly complicated. The SBSSAB is aesthetic in appearance, and design of the SBSSAB is artful and particular. In order to roundly investigate the mechanical behavior of the SBSSAB, 3-D finite element models for spatial member and shell were established to analyze the mechanical properties of the SBSSAB using ANSYS. Finite element analyses were conducted under several main loading cases, moreover deformation and strain values for control section of the SBSSAB under several main loading cases were proposed. To ensure the safety and rationality for optimal design of the SBSSAB and also to verify the reliability of its design and calculation theories, the 1/10 scale model tests were carried out. The measured results include the load checking calculation, lane loading and crowd load, and dead load. A good agreement is achieved between the experimental and analytical results. Both experimental and analytical results have shown that the SBSSAB is in the elastic state under the planned test loads, which indicates that the SBSSAB has an adequate load-capacity. The calibrated finite-element model that reflects the as-built conditions can be used as a baseline for health monitoring and future maintenance of the SBSSAB.

A Dynamic QoS Adjustment Enabled and Load-balancing-aware Service Composition Method for Multiple Requests

  • Wu, Xiaozhu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.3
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    • pp.891-910
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    • 2021
  • Previous QoS-aware service composition methods mainly focus on how to generate composite service with the optimal QoS efficiently for a single request. However, in the real application scenarios, there are multiple service requests and multiple service providers. It is more important to compose services with suboptimal QoS and maintain the load balance between services. To solve this problem, in this paper, we propose a service composition method, named as dynamically change and balancing composition method (DCBC). It assumes that the QoS of service is not static, and the services can adjust the value of QoS to gain more opportunities to be selected for composition. The method mainly includes two steps, which are the preprocessing step and the service selection step. In the preprocessing step, a backward global best QoS calculation is performed which regarding the static and dynamic QoS respectively; then guided by the global QoS, the feasible services can be selected efficiently in the service selection step. The experiments show that the DCBC method can not only improve the overall quality of composite services but also guarantee the fulfill ratio of requests and the load balance of services.