• Journal of KIISE:Computer Systems and Theory
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• v.27 no.5
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• pp.450-463
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• 2000

Array redistribution is usually required to enhance algorithm performance in many parallel programs on distributed memory multicomputers. GEN_BLOCK redistribution, which is redistribution between different GEN_BLOCKs, is essential for load balancing. However, prior research on redistribution has been focused on regular redistribution, such as redistribution between different CYCLIC(N)s. GEN_BLOCK redistribution is very different from regular redistribution. Message passing in regular redistribution involves repetitions of basic message passing patterns, while message passing for GEN_BLOCK redistribution shows locality. This paper proves that two optimal condition, reducing the number of communication steps and minimizing redistribution size, are essential in GEN_BLOCK redistribution. Additionally, by adding a relocation phase to list scheduling, we make an optimal scheduling algorithm for GEN_BLOCK redistribution. To evaluate the performance of the algorithm, we have performed experiments on a CRAY T3E. According to the experiments, it was proven that the scheduling algorithm shows better performance and that the conditions are critical in enhancing the communication speed of GEN_BLOCK redistribution.

• Ocean Systems Engineering
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• v.2 no.4
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• pp.271-287
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• 2012

Due to its large size, a ship is first divided into scores of blocks and then each block is constructed through various shops, such as the assembly shop, the painting shop, and the outfitting shop. However, each block may not be directly moved to the next shop and may be temporarily laid at a block stockyard because the working time in each shop is different from each other. If blocks are laid at the block stockyard without any planning, the rearrangement of the blocks by a transporter is required because the blocks have the different in and out time. In this study, a block layout method based on the genetic algorithm was proposed in order to minimize the rearrangement of the blocks in the block stockyard. To evaluate the applicability of the proposed method, it was applied to simple layout problems of the block stockyard. The result shows that the proposed method can yield a block layout that minimizes the total relocation cost of moving obstacle blocks in the block stockyard.

• Journal of the Korean Institute of Educational Facilities
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• v.18 no.4
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• pp.25-32
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• 2011

This study was carried out to obtain basic data for architectural plans about factors on the facilities relocation needed in management of variation type. For this, floor plans of thirteen middle schools located in Korea and Japan were compared. The results showed a successful conversion to block system according to each subject after remodeling in the schools of our country, however, a monotonous spacial composition excluded other spaces such as media space, teachers' station and preparation room was also shown. These mentioned spaces were important factors in the investigated schools of Japan. By the results of the spacial composition about each space required to the management of variation type, a space share of supplemental areas for learning activities and movement, had shown comparatively low share before remodeling, was improved to 6% and 11.6%, respectively. However, the spacial share of two areas were 16.8% and 12.9%, respectively, in the schools of Japan and it meant the distribution of area was more even than the cases of our country.

• Journal of the Korea Society of Computer and Information
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• v.19 no.11
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• pp.9-15
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• 2014

In this paper, We propose a block reallocation algorithm for reducing network traffic in Hadoop cluster. The scheduler of Hadoop cluster receives a job from users. And the job is divided into multiple tasks assigned to nodes. At this time, the scheduler allocates the task to the node that satisfied data locality. If a task is assigned to the node that does not have the data(block) to be processed, the task is processed after the data transmission from another node. There is difference of workload among nodes because blocks in cluster have different access frequency. Therefore, the proposed algorithm relocates blocks according to the task allocation pattern of Hadoop scheduler. Eventually, workload of nodes are leveled, and the case of the task processing in a node that does not have the block to be processing is reduced. Thus, the network traffic of the cluster is also reduced. We evaluate the proposed block reallocation algorithm by a simulation. The simulation result shows maximum 23.3% reduction of network consumption than default delay scheduling for jobs processing.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.117-126
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• 2014

In this paper, we propose an efficient algorithm which can relocate the datablock of an aircraft when it is overlapped. If the datablock which represents the aircraft information in the control display is overlapped, relocation without overlapping is necessary because it is difficult to control the air traffic in this situation. The proposed algorithm relocates the data block with minimum movement by considering the characteristics of datablock. The moving distance of minimum movement is calculated using the height or width of rectangle which is created during overlapping. And the moving direction of minimum movement is calculated by considering the directivity of the datablock. When the distance between the target symbol and datablock is distant enough, the relocation is carried out using the existing algorithm as a special case. The proposed algorithm shows improved performance in comparison with the existing algorithm due to the fact that it considers many different cases of the datablock.

• Journal of the Korea Society of Computer and Information
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• v.16 no.6
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• pp.21-30
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• 2011

In the global IT market, a lot of issues for responding to various environmental regulations emerged. In case of the data centers, it is consuming huge amounts of energy to maintain. So there have been various technical attempts as Consolidation, Virtualization, Optimization to efficiently manage energy and data storage to fix the problems. In this paper, we propose a new RAID(Redundant Array of Independent Disks) mechanism which is differing the intensity of power consumption and works to provide data protection and disaster recovery(backup, mirroring etc.) to stratify multiple volumes. G-RAID minimize the power consumption and the lower of I/O performance by selecting the volume depending on the frequency of data access while classifying the power consumption between volumes in storage system. Also, it is possible that a filesystem and block map information of G-RAID is processed by basic unit which is group located in a row for the blocks to work efficiently and can minimize the performance degradation of block mapping load by the access frequency in each groups. As a result, we obtained to elevate a little bit of response time caused by block relocation work, but showed the decrease of power consumption by 38%.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.61-70
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• 2020

In this study, the IOT-based desk layout method was proposed to complement the existing seating method and to improve the work efficiency. The IoT system for the desk layout needs determining the function, type and network protocol of the sensor to find out the working status of the desk to reasonably assist the worker's seat placement. A collection method was proposed. The algorithm used in Block Stacking was used when deciding how to allocate seats using the acquired data. As a result, we could suggest an arithmetic basis for rational desk layout in IoT environment and show that it can be applied to an advanced flexible seating system based on working type in addition to the preferences of employees in the future.

• Journal of Korean Institute of Industrial Engineers
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• v.35 no.1
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• pp.58-72
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• 2009

The main activities of container terminals are to load container freights to vessels, discharge them from vessels, and store them in the storage yard. Container terminals make many operational plans to execute these functions effectively. If the plans do not consider enough the loads of related resources, they may have low actualities. This study discusses the optimal yard planning model which considers various resources, such as the storage yard, yard cranes, internal vehicles, and travel lanes, in container terminals. The model determines the groups and amounts of containers which are stored in each storage block by using the resource profile. The yard planning problem is represented to the multi-commodity minimal cost flow problem and is formulated to the linear programming model. In order to explain the application of the mathematical model, the numerical examples are presented. Additionally, the relationship between the average load ratio and the relocation ratio is discussed.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.1697-1700
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• 2005

파일에 대한 분할과 재결합은 네트워크를 통한 대용량 파일 전송 시에 자주 사용되는 연산이다. 위 연산들은 현재 유저 레벨의 어플리케이션에 의해 제공되고 있어 동일한 데이터를 외부 장치내에서 복사하는 불필요한 동작을 수행한다. 이러한 단점을 제거하기 위해 커널 레벨의 파일 시스템에 I-node 간의 디스크 블록 재배치를 수행하는 연산을 설계하였다. 그리고 새로운 분할과 재결합 연산을 구현한 파일 시스템 시뮬레이터로 실험을 수행하여 성능을 평가하였다. 결과적으로, 64Mbytes 크기의 파일에 대해 분할 연산은 399 배, 재결합 연산은 682 배의 수행 시간 감소를 보여주었다.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.4
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• pp.19-29
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• 2018

This study examines the 1960s' townscape through the small-scale restoration model in Seongan-dong and Jungang-dong, Cheongju, one of the historical cities in South Korea. In the 1960s, Jungang-dong actively was developed outside the north gate of Cheongju castle, and Cheongju's townscape was changed by the relocation of railway station and construction of city hall. In the streetscape, the new roads, the east-west Sajik-ro and north-south Sangdang-ro were opened instead of old railroads, and they clarified the typical grid road system with the existing Seongan-ro, which connected north and south gate of the old castle. In the buildingscape, city hall was built in front of the railway station outside the north gate of old castle, and had a great effect on the existing buildings and facilities. The public, educational, and commercial buildings had been replaced by reinforced concrete, and the cement brick & block public housing were distributed widely. But the existing dwelling areas, located in the inside of old castle and outside south gate, showed the low and dense townscape, sustaining the former streets and building types.