• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2003.11a
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• pp.164-180
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• 2003

A series of cooperative interlaboratory tests (round robins) was conducted in 1997, 1998, 1999, 2000, 2001, 2002 and 2003 by the DIN 51834 Working Group on Tribological Tests in Translatory Oscillation Apparatus. The statistical analysis of these test results shows the influence of cleaning solvent, machine model and evaluation criteria on the tribological properties of the lubricants tested. Coefficients of friction and wear results are ranked according to the effects of ten different cleaning solvents, where isopropanol gave the lowest values and isoparaffin solvents the highest. The effect of machine model on coefficients of friction varied from about $0.2\%\;to\;0.9\%$ of the mean. Wear results were not affected. The tests also showed that the seizure criteria and methods of measuring wear required for in the test procedure do not provide a suitable measure of the tribological properties of some lubricants. The precision was Improved by introducing a grease apply caliper as well as an increased stroke to 1,5 mm and running-in. The temperature does not affect the precision of the oil test procedure.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.2B
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• pp.107-116
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• 2006

In this paper, we propose a Sensing Resolution-based Grouping(SRG) protocol for wireless sensor networks. SRG is intended for meeting the application's sensing objectives, where sensor nodes are densely deployed and have the determinate accuracy requirement. The primary contribution of this paper is active group header node selection and round-robin procedure, which increase the sensing accuracy and evenly distribute the node energy consumption. The second contribution is use of energy efficient intermediate node selection by considering group size and energy consumption. We present the design principle of SRG and provide simulation results.

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.275-278
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• 2000

Recently ATM(Asynchronous Transfer Mode) technology is facing challenges from Integrated Service IP(Internet Protocol), IP router, Gigabit Ethernet. Although ATM is approved by ITU-T as the standard technology in B-ISDN, its survival is still in question. In the ATM networks, the Guaranteed Frame Rate(GFR) service has been designed to accommodate non-real-time applications, such as TCP(Transmission Control Protocol)/IP based traffic. The GFR service not only guarantees a minimum throughput at the frame level, but also supports a fairshare of available resources. We have studied different discarding and scheduling schemes, and compared their throughput and fairness when TCP/IP Traffic is carried. Through simulations, we know that only per-VC queueing with weighted Round Robin(WRR) can guarantee Minimum Cell Rate Among all the Schemes that have been experimented, we recommend DT-EPD(Dynamic Threshold-Early Packet Discard) integrated with MCRplus(Minimum Cell Rate) to support the GFR service.

• ETRI Journal
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• v.40 no.3
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• pp.337-346
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• 2018

In this paper, we propose a grant-aware (GA) scheduling algorithm that can provide higher throughput and lower latency than a conventional dual round-robin matching (DRRM) method. In our proposed GA algorithm, when an output receives requests from different inputs, the output not only sends a grant to the selected input, but also sends a grant indicator to all the other inputs to share the grant information. This allows the inputs to skip the granted outputs in their input arbiters in the next iteration. Simulation results using OPNET show that the proposed algorithm provides a maximum 3% higher throughput with approximately 31% less queuing delay than DRRM.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2205-2213
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• 1993

The characteristic test for gage factors of temperature self-compensated strain gages at cryogenic temperature is presented. By joining the international round robin test on electrical strain gages at cryogenic temperatures, the gage factors of three kinds of widely-used strain gages are obtained at the room temperature, the temperatures of liquid nitrogen and liquid helium. The calibration system which produce precise bending strain is by mechanical loading at cryogenic temperature. This paper also presents the creep characteristic of strain gages at maximum strain level.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.417-419
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• 2004

Because of the demands for high performance and high integrated system, the needs for optimal platform becomes more importance. Optimal platform can handle more data effectively with same resources. AMBA(Advanced Microprocessor Bus Architecture)$^{TM}$ defines on-chip communication standard for designing high performance embedded micro-controllers. It is consisted of AHB, ASB and APB. It can support fast implementation and reliability in system that is composed with reusable IPs. DMAC is one of master in system and generate master signals of AHB to communicate data from one slave(peripheral or memory) to another slave. It can reduce burden of CPU and increase system performance. We designed DMAC based on AMBA and it supports 13 Channels. Each channel can be controlled by software program. It decides channel's priority using round-robin method. It can support P2P, P2M, M2P and P2P communication.

• Proceedings of the Korean Reliability Society Conference
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• 2001.06a
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• pp.245-255
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• 2001

원전 가동전/가동중검사 결과의 신뢰도(reliability)는 원전 배관기기의 건전성에 직결되는 것으로써 결함 발견 시 적용되는 파괴역학해석(FMA)은 비파괴검사 결과에 대한 100%의 신뢰를 전제하고 있다. 그러나 비파괴검사가 어느 정도 신뢰성을 가지고 있는지에 대한 평가가 국내에서는 거의 수행된 바가 없었다. 따라서, 본 연구에서는 원전의 비파괴검사 규제 요건의 기술적 근거를 확보하고, 원전 기기 건전성 평가 및 안전성 향상을 위한 합리적 규제지침을 수립하기 위하여 국내 원전 가동중검사(ISI)에 적용되거나 일반 산업계에 적용되고 있는 초음파탐상검사에 대하여 기량검증 Round Robin Test에 의한 통계적 신뢰도를 평가하고자 한다. 이를 위해 초음파검사 PD-RRT 결과의 통계적 신뢰도 평가 모델을 고찰하고, 결함검출성능 평가, 결함크기 측정 평가, 팀 오차 분석 등 초음파검사 PD-RRT 결과의 통계적 신뢰도를 평가하였다.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.1
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• pp.19-26
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• 2016

In the consumer products industry, it has been highly desirable to develop objective test methods to replace subjective evaluation methods. In developing an objective test method, subjective evaluation data should be on a linear scale. According to Thurstone's theory of comparative judgment, a%-preference from a paired-comparison test can be converted to a linear-scale value. The required number (N) of paired-comparison tests increases dramatically as the number of products increases. This problem should be solved by classifying the total products into several subgroups consisting of 3-4 products in each group. By doing so, it can not only significantly reduce the number of required paired-comparison tests, but it can also obtain more reliable, reproducible data.

• Journal of Digital Convergence
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• v.6 no.2
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• pp.117-125
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• 2008

High-volume web sites often use clusters of servers with load balancing as a way to increase the performance, scalability, and availability of the sites. Load balancing, usually performed by load balancer in front of such clusters, is a technique to spread workload between several computers or resources, in order to get optimal resource utilization or response time. In this paper we examine the performance for several configurations of cluster-based web servers using a simulation approach. We investigate two types of buffering scheme (common and local) for web clusters and three load balancing policies (uniformly random, round robin, and least queue first), using response time as a performance measure. We also examine two basic approaches of scaling web clusters: adding more servers of same type or upgrading the capacity of the servers in the clusters.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.8
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• pp.1414-1421
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• 2006

This paper proposes a consistency algorithm that is able to serve streaming data efficiently in VOD system. The media data is stripping into several pieces of data by the Round Robin method in order to media data service. The barrier mechanism is changed into the minimum data factor(SH. GOP) in this paper. The shared memory is allocated at one host with one fragment size. Data is combined with RTP packet transmission data format using barrier mechanism. I experiment and program the suggested algorithm on the VOD system.