• The Journal of Korean Institute for Practical Engineering Education
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• v.5 no.1
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• pp.20-27
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• 2013

The counter balancing is a technique to control a load which is acting to actuator when the load changes from a resistance state to over running state according to the structural change of the load for the case of lifting or carrying a heavy load in industrial site. Even though this technique is frequently used in industrial site, there is no widely known design procedure and educational equipment in home and abroad. Therefore, in this study a new idea was presented to develop an counter balancing educational equipment. The idea was realized through the process of system modeling and simulation, drawing out of design parameters, manufacturing of a prototype. Finally the usefulness of this developed educational equipment was demonstrated by experiments. It is expected that by using this equipment a big help would be given to students who should understand the counter balancing equipment which is frequently encountered in industrial site.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1293-1296
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• 1997

We investigate a design methodology for master arm which is employed in remote-site control. Though counter-balancing has been employed for the purpose of lessening the actuator loads, it results in the increase of dynamic load at the task position. Therefore, there exist a trade-off between counter-balacing and dynamic performance. The concept of a composite index is introduced to simulataneously consider those two effects in the design of master arms. Several alternative designs of master arms are suggested.

• Journal of Korea Foundry Society
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• v.40 no.2
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• pp.34-42
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• 2020

The effects of the initial balancing pressure, filling pressure and maximum build-up pressure on the casting characteristics of the thick-wall thickness casting during the counter-pressure casting process were investigated. Water model experiment and a computer simulation were carried out to evaluate the characteristics during the filling and solidification stages in counter-pressure casting (CPC); as a reference, the low-pressure casting (LPC) process was used. The average dendrite cell size decreased with an increase in the solidification rate and maximum build-up pressure. A turbulent flow occurred during the filling stage of the LPC process, resulting in the formation of inner gas, while a lamellar flow pattern dominated during the CPC process and was more evident with an increase in the initial balancing pressure, improving the mechanical properties of the castings.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.3
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• pp.233-239
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• 2013

This paper presents the analysis and control of the position of the COG (Center of Gravity) for a two-wheel balancing robot. The two-wheel balancing robot is required to maintain balance by driving two wheels only. Since the robot is not exactly symmetrical and its dynamics is changing with respect to moving parts, robust balancing control is difficult. Balancing performance becomes difficult when two arms hold a heavy object since the center of gravity is shifted out of the wheel axis. Novel design of a sliding waist mechanism allows the robot to react against the shift of the COG by moving the whole upper body to compensate for the imbalance of the mass as a counter balancer. To relocate the COG position accurately, the COG is analyzed by force data measured from two force sensors. Then the sliding COG mechanism is utilized to control the sliding waist position. Experimental studies are conducted to confirm the proposed design and method.

• ETRI Journal
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• v.27 no.1
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• pp.110-113
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• 2005

The resilient packet ring (RPR) is a data optimized ring network, where one of the key issues is on load balancing for competing streams of elastic traffic. This paper suggests three efficient traffic loading algorithms on the RPR. For the algorithms, we evaluate their efficiency via analysis or simulation.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.12
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• pp.148-161
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• 1998

We investigate a design methodology for master arm which is employed in remote-site control. Though counter-balancing has been employed for the purpose of lessening the actuator loads, it results in the increase of dynamic load at the task position. Therefore, there exists a trade-off between counter-balancing and dynamic performance. The concept of a composite index is introduced to simultaneously consider those two effects in the design of master arms. Several alternative designs of master arms are suggested.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11a
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• pp.143-146
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• 2002

웹 서비스를 제공하는 분산 서버 시스템에서 각 서버의 부하 상태를 파악하여 처리해야 할 부하를 조절하여 주면 서버의 부하가 균등하게 되어 더 나은 성능을 얻을 수 있게 된다. 서버의 부하 상태는 시스템의 자원에 영향을 미치는 여러 가지 요소에 의하여 분석을 할 수 있다. 본 논문에서는 다양한 스트레스 테스트를 통하여 서버의 자원의 고갈을 나타내는 주요 성능 지표들을 변화 상태를 분석하였다. 고려된 성능지표로는 Available Memory 양, Page Read 수, Processor Utilization, Processor Queue Length, 네트웍으로 전달된 Transmitted Bytes, 연결된 Connection 개수이다. 실제로 이중 하나의 요소를 적용시켜서 ALBM (Adaptive Load Balancing Mechanism)을 실행을 하였을 때 일반 LVS Round Robin 보다 성능이 좋은 결과를 낳았다.

• The KSFM Journal of Fluid Machinery
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• v.12 no.4
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• pp.23-29
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• 2009

For the purpose of high outlet pressure, compactness and low vibration and noise, 2 stage reciprocating air compressors can have various cylinder arrangement: opposed, in-line, and V type. This paper presents an effective method to calculate the inertia forces and to design counter weight. This method is based on the complex representation for the orbital behavior of the compressor shaft. This method helps to find the optimal balancing rate easily to reduce the inertial force or moment. This paper shows that the residual inertia forces of the single throw shafts and the residual inertia moments of the double throw shafts remain to be imbalanced.

• Journal of Korea Multimedia Society
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• v.5 no.5
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• pp.477-487
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• 2002

In a VOD system, it is desirable to provide the user with interactive VCR functions such as fast-forward and fast-backward. Typically, these functions can be implemented using the segment interleaving technique in disk away based VOD servers. But the segment interleaving nay not ensure QoS of users because of the concentrated load within some disks. In this paper, we propose an efficient load balancing technique for evenly distributing the retrieval requests across the disks. The proposed technique maintains an access counter in each disk, which has the number of disk accesses. The fast-forward/backward can be achieved by choosing a segment to be accessed from the disk with the minimum number among the access counters. We conduct simulation experiments and then show that our proposed technique outperforms the previous ones.

• Genomics & Informatics
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• v.12 no.3
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• pp.87-97
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• 2014

Although the number of protein-coding genes is not highly variable between plant taxa, the DNA content in their genomes is highly variable, by as much as 2,056-fold from a 1C amount of 0.0648 pg to 132.5 pg. The mean 1C-value in plants is 2.4 pg, and genome size expansion/contraction is lineage-specific in plant taxonomy. Transposable element fractions in plant genomes are also variable, as low as ~3% in small genomes and as high as ~85% in large genomes, indicating that genome size is a linear function of transposable element content. Of the 2 classes of transposable elements, the dynamics of class 1 long terminal repeat (LTR) retrotransposons is a major contributor to the 1C value differences among plants. The activity of LTR retrotransposons is under the control of epigenetic suppressing mechanisms. Also, genome-purging mechanisms have been adopted to counter-balance the genome size amplification. With a wealth of information on whole-genome sequences in plant genomes, it was revealed that several genome-purging mechanisms have been employed, depending on plant taxa. Two genera, Lilium and Fritillaria, are known to have large genomes in angiosperms. There were twice times of concerted genome size evolutions in the family Liliaceae during the divergence of the current genera in Liliaceae. In addition to the LTR retrotransposons, non-LTR retrotransposons and satellite DNAs contributed to the huge genomes in the two genera by possible failure of genome counter-balancing mechanisms.