• Journal of the Korea Society for Simulation
• /
• v.2 no.1
• /
• pp.91-106
• /
• 1993

Load sharing in distributed systems improves systems performance. Research in the field has been focused on steady state performance for load sharing algorithms. However, transient characteristics of such algorithms may be important in a distributed system in which workload for some node is changing. Simulation is the only means to analyze such characteristics. This paper presents a simulation-based analysis of the transient characteristics of four load sharing algorithms ; forward probing, reverse probing, symmetric probing, and multi-threshold symmetric probing algorithms. Discrete event system models for execution of the algorithms in a distributed system has been developed in a SIMSCRIOT II.5 environment. Simulation results indicate that the MSYM algorithm shows the shortest response time in the transient period.

• Geomechanics and Engineering
• /
• v.36 no.6
• /
• pp.545-561
• /
• 2024

Piled raft foundation has become widely used in the recent years because it can increase bearing capacity of foundation with control settlement. The design for a piled raft in terms vertical load and lateral load need to understands contribution load behavior to raft and pile in piled raft foundation system. The load-bearing behavior of the piled raft, especially concerning lateral loads, is highly complex and challenge to analyze. The complex mechanism of piled rafts can be clarified by using three dimensional (3-D) Finite Element Method (FEM). Therefore, this paper focuses on free-standing head pile group, on-ground piled raft, and embedded raft for the piled raft foundation systems. The lateral resistant of piled raft foundation was investigated in terms of relationship between vertical load, lateral load and displacement, as well as the lateral load sharing of the raft. The results show that both vertical load and raft position significantly impact the lateral load capacity of the piled raft, especially when the vertical load increases and the raft embeds into the soil. On the same condition of vertical settlement and lateral displacement, piled raft experiences a substantial demonstrates a higher capacity for lateral load sharing compared to the on-ground raft. Ultimately, regarding design considerations, the piled raft can reliably support lateral loads while exhibiting behavior within the elastic range, in which it is safe to use.

• The Journal of the Korea Contents Association
• /
• v.5 no.3
• /
• pp.183-191
• /
• 2005

In a sender-initiated load sharing algorithms, sender(overloaded processor) continues to send unnecessary request messages for load transfer until receiver(underloaded processor) is found while the system load is heavy. Therefore, it yields many problems such as low CPU utilization and system throughput because of inefficient inter-processor communications until the sender receives an accept message from the receiver in this environment. This paper presents an approach based on genetic algorithm(GA) for dynamic load sharing in heterogeneous distributed systems. In this scheme the processors to which the requests are sent off is determined by the proposed GA to decrease unnecessary request messages.

• Journal of KIISE:Information Networking
• /
• v.29 no.5
• /
• pp.466-472
• /
• 2002

We investigate the load sharing problem between the umbrella cell and the overlaid tells in hierarchical cell structure. A load sharing strategy is proposed and its performance is evaluated by simulation when it is used for transmission of the mobile Internet traffic using the High Speed Downlink Packet Access scheme. The results show that, with the proposed strategy, the microcell backs well the overlaid picocells up, especially when a specific picocell cluster suffers unusual heavy load condition. By using the strategy, we can reduce the installation cost, otherwise needed for increasing the system capacity of every picocell cluster to cope with the unusual heavy load.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.8
• /
• pp.3603-3609
• /
• 2011

In this paper, we proposes new load-sharing algorism for equal current division using CAN communication. Proposed algorithm is different from conventional analog method, it performed strong Load-sharing using bi-direction high speed communication. Each modules constitution on independence controller (voltage controller, electric current controller). In parallel system prototype, each module have controller and performed load-sharing according to master module integral value. Also additional controller use for getting each module situations that fault situation of module and fault locate of module. we implemented high efficient load-sharing and redundancy. In this paper, we verify the validity of proposed algorithm using PSIM program and prototype.

• Journal of the Korean Geosynthetics Society
• /
• v.22 no.1
• /
• pp.39-51
• /
• 2023

The bearing capacity of the prebored pile has been studied by many researchers. However, The bearing capacity of the prebored pile has been studied by many researchers. However, comparative studies between design data and pile load test data on the load sharing ratio and the settlement were insignificant. Therefore, the design data and the static load test results were compared for the prebored open-end steel piles. In the compressive static pile load test, the load sharing ratios of the base resistance and the shaft resistance were 13%~40% and 60%~87%, respectively and the settlements were measured 2.2mm~4.7mm. In the current bearing capacity calculation formula, the base resistance was shared between 54% and 75%, and the shaft resistance was shared between 25% and 46% and the settlements were calculated about 19.8mm~23.6mm. The settlement in the current bearing capacity calculation formula was 321% to 776% (average : 445%) larger than the settlement in the result of load test. When the settlement were calculated using the load sharing ratio in the pile load tests, it was 137% to 525% larger than the test settlement, and it was as large as 204% on average. It was confirmed that an appropriate evaluation of the load sharing ratio had an important effect on the calculation of pile settlement.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• v.9 no.2
• /
• pp.1053-1057
• /
• 2005

현재 IETF (Internet Engineering Task Force)의 SHIM6 (Site Multihoming by IPv6 Intermediation) 워킹그룹에서는 Network layer Shim (L3shim)이라는 새로운 IPv6 스택을 정의하여IPv6 환경에서 멀티호밍을 지원하는 방법에 대해 표준을 제정하고 있다. 이 Multihoming은 redundancy, load sharing과 같은 멀티호밍 장점을 지원할 수 있다. 본 논문은 이와 같이 새롭게 정의된 L3shim이 단말에 있을 경우, 단말에서 효과적인 Policy 정책을 통한 load sharing 및 balancing 통한 traffic engineering 방법을 제시한다. 현재 SHIM6 워킹그룹에서는 L3shim을 이용한 load balancing 부분은 다루고 있지 않다. 그러나 멀티호밍의 장점 줌 하나는load balancing이며 실제 load balancing이 지원 됐을 경우 응용 차원에서 많은 장점을 가질 것으로 여겨진다. 따라서 이와 관련한 메커니즘이 필요하며, 이를 위한 선행적인 연구가 필요로 되어진다.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.35 no.1
• /
• pp.24-31
• /
• 2012

This study is designed to predict the overall electric power load, to apply the method of time sharing and to reduce simultaneous load factor of electric power when authorized by user entering demand plans and using schedules into the user's interface for a certain period of time. This is about smart grid, which reduces electric power load through simultaneous load factor of electric power reduction system supervision agent. Also, this study has the following characteristics. First, it is the user interface which enables authorized users to enter and send/receive such data as demand plan and using schedule for a certain period of time. Second, it is the database server, which collects, classifies, analyzes, saves and manages demand forecast data for a certain period of time. Third, is the simultaneous load factor of electric power control agent, which controls usage of electric power by getting control signal, which is intended to reduce the simultaneous load factor of electric power by the use of the time sharing control system, form the user interface, which also integrate and compare the data which were gained from the interface and the demand forecast data of the certain period of time.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2005.03a
• /
• pp.65-70
• /
• 2005

In this study, the large scale model tests were executed to estimate the Load Sharing Ratio(LSR) of raft in a piled footing under various conditions. The conditions such as the subsoil type, pile length, pile spacing, array type and pile installation method etc. were varied in the pile loading tests about the free-standing group piles and a piled footing. As the results of this study, it was found that there were no differences of the load-settlement curves, along with the pile installation method and subsoil type. The piles supported most of the external load until a yielding load of the piled footing, but the raft supported a considerable load after a yielding load. And it was also found that the LSR didn't be affected by the pile installation method and the subsoil type. As the relative density of sands increased, the LSR decreased. As the pile spacing was wider and the pile length increased, there was a tendancy for the LSR to increase.

• Geomechanics and Engineering
• /
• v.24 no.1
• /
• pp.29-42
• /
• 2021

The utilization of buildings can be improved by extending them vertically. However, the added load of the extension might require building foundations to be underpinned; otherwise, the loads on the foundations might exceed their bearing capacity. In this study, a preloading method was presented aiming at transferring partial loads from existing piles to underpinning piles. A pneumatic-type model preloading device was developed and used to carry out centrifuge experiments to evaluate the load-displacement behavior of piles, the pile-soil interaction during preloading, and the additional loading caused by vertical extension. The results showed that the preloading devices effectively transfer load from existing piles to underpinning piles. In the additional loading test of group piles, the load-sharing ratio of a pile increased with its stiffness. The load-sharing ratio of a preloaded micropile was less than that of a non-preloaded micropile as a result of the reduction in axial stiffness caused by preloading before additional loading. Therefore, a slight reduction of the load-sharing capacity of an underpinning pile should be considered if the preloading method is applied. Further, two full scale preloading devices was developed. The devices preload underpinning piles and thereby produce reaction forces on a reaction frame to jack existing piles upward, thus transferring load from the existing piles to the underpinning piles. Specifically, screw-type and hydraulic-jack type devices were developed for the practical application of foundation underpinning during vertical extension, and their operability and load transfer effect verified via full-scale structural experiments.