• Title/Summary/Keyword: Collection

Search Result 11,655, Processing Time 0.038 seconds

Garbage Collection Protocol of Fault Tolerance Information in Multi-agent Environments (멀티에이전트 환경에서 결함 포용 정보의 쓰레기 처리 기법)

  • 이대원;정광식;이화민;신상철;이영준;유헌창;이원규
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.31 no.3_4
    • /
    • pp.204-212
    • /
    • 2004
  • Existing distributed systems have higher probability of failures occurrence than stand-alone system, so many fault tolerant techniques have been developed. Because of insufficient storage resulting from the increased fault tolerance information stored, the performance of system has been degraded. To avoid performance degradation, it needs delete useless fault tolerance information. In this paper, we propose a garbage collection algorithm for fault tolerance information. And we define and design the garbage collection agent for garbage collection of fault tolerance information, the information agent for management of fault tolerant data, and the facilitator agent for communication between agents. Also, we propose the garbage collection algorithm using the garbage collection agent. For rollback recovery, we use independent checkpointing protocol and sender based pessimistic message logging protocol. In our proposed garbage collection algorithm, the garbage collection, information, and facilitator agent is created with process, and the information agent constructs domain knowledge with its checkpoints and non-determistic events. And the garbage collection agent decides garbage collection time, and it deletes useless fault tolerance information in cooperation with the information and facilitator agent. For propriety of proposed garbage collection technique using agents, we compare domain knowledge of system that performs garbage collection after rollback recovery and domain knowledge of system that doesn't perform garbage collection.

A study of collection evaluation using conspectus methodology (컨스펙터스방법을 이용한 장서평가연구)

  • 박진희
    • Journal of the Korean Society for information Management
    • /
    • v.15 no.2
    • /
    • pp.163-191
    • /
    • 1998
  • The im of the present study is to introduce and develop the concept and theory of conspectus for the first time in Korea, and to propose a new evaluation model for book collection by actually applying the developed methodology to the collection of a special library dedicated to Biblical Studies. Conspectus is a standardized and objective evaluation method that classifies the main collection according to the division, category, subject, and then gives each collection ots appropriate collection level code by analyzing the classified collection in terms of three different dimensions, which are Current Collection Level(CL), Acquisition Commitment Level(AC), and Collection Goal Level(GL). To evaluate the collection of the sample library, shelflist analysis, list checking, acquisition data in ordering process by their main subject, and survey of its users have been carried out, and all of their results ahve been indicated in terms of eleven collection level codes developed by WLN Conspectus. T e collection of sample library was evaluated as '3cW' for CL, '4W' for AC, and '4W' for GL when the Conspectus methodology was applied for evaluation. This study could be utilized as an collection evaluation model for theological libraries, and become a basis to bring about more active cooperative collection development among related libraries.

  • PDF

Draft genome sequence of Senegalimassilia sp. KGMB 04484 isolated from healthy Korean human feces (건강한 한국인 분변으로부터 분리된 Senegalimassilia sp. KGMB 04484 균주의 유전체 염기서열 초안)

  • Han, Kook-Il;Kang, Se Won;Kim, Ji-Sun;Lee, Keun Chul;Eom, Mi Kyung;Suh, Min Kuk;Kim, Han Sol;Park, Seung-Hwan;Lee, Ju Huck;Park, Jam-Eon;Oh, Byeong Seob;Yu, Seung Yeob;Choi, Seung-Hyeon;Lee, Dong Ho;Yoon, Hyuk;Kim, Byung-Yong;Lee, Je Hee;Lee, Jung-Sook
    • Korean Journal of Microbiology
    • /
    • v.55 no.2
    • /
    • pp.160-163
    • /
    • 2019
  • Senegalimassilia sp. KGMB 04484 was isolated from fecal samples obtained from a healthy Korean. The whole-genome sequence of Senegalimassilia sp. KGMB 04484 was analyzed using the PacBio Sequel platform. The genome comprises a 2,748,041 bp chromosome with a G+C content of 61.18%, 2,300 total genes, 2,139 protein-coding gene, 21 rRNA genes, and 51 tRNA genes. Also, we found that strain KGMB 04484 had some genes for hydrolysis enzyme, fatty acid biosynthesis and metabolism in its genome based on the result of genome analysis. Those genes of KGMB 04484 may be related to regulation of human health and digest.

A Study far Improvement of Disposal and Collection System of Agricultural PE Waste (농업용 폐비닐의 농가처리 및 수거제도 개선방안)

  • Kang, Chang-Yong
    • Journal of Environmental Policy
    • /
    • v.2 no.1
    • /
    • pp.51-75
    • /
    • 2003
  • The objective of this study is to analyze the problems of disposal and collection, including administrative management of agricultural PE waste and suggest effective management measurements. Information regarding problems of agricultural PE waste management were collected from field survey of farmers, regional governments and officials. On the national level, the low ratio of collection for optimal treatment of agricultural PE waste is a critical problem. , the negative discharging behavior of farmers, an illegal incineration and landfill of farmers and a lack of education and extension etc. An ambiguity of the management principle to agricultural PE waste, the differences in management among the regional governments, a lack of will of the regional governments and officials to realize SARD and lack of education and extension etc. are some of the problems in administrative management of agricultural PE waste collection. The major suggestions of this study are as follows : (1) to strengthen education and extension, (2) to adopt an improved economic incentive system and strong, lawful regulation simultaneously, (3) to use temporang collection and permanent collection site, and (4) to organize "OTC(Optimal Treatment Conference)" composed of farmers, regional cooperative, PE producers etc. for operating an effective management system.

  • PDF

Effect of Secondary Flows on the Particle Collection Efficiency in Single Stage Electrostatic Precipitator (1단 전기 집진기에서 2차 유동이 집진 효율에 미치는 영향)

  • Lee, Jae-Bok;Bae, Gwi-Nam;Hwang, Jung-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.24 no.2
    • /
    • pp.251-259
    • /
    • 2000
  • The ionic wind formed in a nonuniform electric field has been recognized to have a significant effect on particle collection in an electrostatic precipitator(ESP). Under normal operating conditions the effect of ionic wind is not pronounced. However, as the flow velocity becomes smaller, the ionic wind becomes pronounced and induces secondary flow, which has a significant influence on the flow field and the particle collecting efficiency. In this paper, experiments for investigating the effect of secondary flow on collection efficiencies were carried out by changing the flow velocities in 0.2-0.7m/s and the applied voltages in 9-11kV/cm. The particle size distributions and concentrations are measured by DMA and CNC. To analyze the experimental results, numerical analysis of electric filed in ESP was carried out. It shows that particle collection is influenced by two independent dimensionless numbers, $Re_{ehd}\;and\;Re_{flow}$ not by $N_{ehd}$ alone. When $Re_{flow}$, decreases for constant $Re_{ehd}$, the secondary flow prohibits the particle collection. But when $Re_{ehd}$ increases for constant $Re_{flow}$, it enhances the particle collection by driving the particles into the collection region.

Characteristics of Seed and Plant Growth in Local Collections of Agastache rugosa

  • Ok, Hyun-Chung;Chae, Young-Am
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.43 no.4
    • /
    • pp.269-272
    • /
    • 1998
  • Characteristics of seed and plant growth of the nine local collections of the medicinal plant, Agastache rugosa were evaluated. Seed size of the collection from Garyungsan was larger than the others. Seeds of Damyang collection were the smallest in size. Seeds of the collections were mostly oval shaped. There were no differences between brown and black seed coat color groups in seed width, ratio of seed length to seed width and 1,000 seed weight. Stem lengths of Garyungsan and Bongpyung collections were 99.9 and 95.6 cm, respectively, and were longer than Damyang and Jindo collections. Garyungsan collection had long leaf shape. Leaf size was the smallest for Damyang collection, but was the largest for Bongpyung collection. Inflorescence length of Mokpo collection (15.6 cm) was longer than the average over all collections (12.3 cm). Damyang collection was the shortest (10.1 cm) in inflorescence. Top dry weight of each collection from Soonchun, Bongpyung, Mokpo, Jindo, and Gurye was greater than the average over all collections (20.38 g/plant). Jinju and Damyang collections had less top dry matter than others. There was no difference in the growth traits examined between brown and black seed coat groups. The brown seed group was greater in leaf weight than the black seed group. However, these two groups were not different in stem and inflorescence weight. Collections of A. rugosa from Bongpyung, Soonchun, and Mokpo were promising for commercial cultivation because of their great top dry weight, especially in leaf and inflorescence.

  • PDF

A Study on Quantity and Quality of Collected Rainwater by Collected Materials (우수 이용을 위한 포집재료별 포집수량과 수질에 관한 연구)

  • Lee, Young-Bok;Lee, Seung-Keun;Wang, Chang-Keun
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.18 no.1
    • /
    • pp.66-72
    • /
    • 2004
  • In this study, quantity and quality of collected rainwater by sand, gravel, soil, lawn and concrete surface, as collection materials were investigated and Rainwater Collection Prediction Model was developed to predict the amount of collected rainwater. The quantity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 1,067L(93.2%), 1,006L(87.8%), 902L(78.8%), 800L(69.9%), 788.5L(68.8%) for 8 months period, respectively. The average turbidity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 3.2NTU, 2.2NTU, 1.9NTU, 1.7NTU, 1.5NTU for 8 months period, respectively. For sand collection material, predicted amount by the Model and actual collected amount were 931.5L and 902L, which were very closed. For gravel collection material, predicted amount by Model and actual collected amount were 1,028.21. and 1,006L, which were very closed. To simulate the optimal rainwater storage volume, the rainfall and evaporation data in Dae-jeon city were used. For sand collection system with 30m2 area, the maximum storage volume was $17m^3$ and 62% of the year was secured for use of 240L/day.

A Descriptive Study on the Collection Development Processes in School Libraries: Based on the Interviews with Teacher Librarians (학교도서관 장서개발과정에 관한 현상적 연구: 사서교사의 인식을 중심으로)

  • Chang, D.H.;Kang, E.Y.
    • Journal of Korean Library and Information Science Society
    • /
    • v.47 no.3
    • /
    • pp.241-259
    • /
    • 2016
  • This study attempts to investigate the current stage of collection development process in school libraries based on interviews with 20 teacher-librarians in school libraries. Library Collection is the primary element of a library and collection development is the starting point of librarians' duty. The researchers shed light on such issues as observed in collection development process in school libraries. Through the visits and observations such problems as aging book collections, lack of support of administrators, imbalance in subject distribution are identified.

The Sludge Collection Scheduling and Vehicle Routing Strategies (하수처리시설의 슬러지 수거 일정계획 수립 및 수거차량 경로결정)

  • Kim Min-Je;No Ui-Su;Heo Eun-Jeong;Choi Gyeong-Hyeon
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 2006.05a
    • /
    • pp.1170-1177
    • /
    • 2006
  • We apply VRP(Vehicle Routing Problem) to sludge collection system in this study. Sewage stores of villages are located in each village around a multipurpose dam. Sludge which is produced in sewage store of village is transported from the sewage store of village to the sewage treatment plants by the special purpose vehicle such as the tank lorry. In this paper, we propose sludge collection strategies which allocate each sewage store of village to sewage treatment plants and decide the schedule of sludge collection in order to collect sludge efficiently. The strategies aim to decrease transportation cost with deciding proposed vehicle routing and scheduling the sludge collection. When we decide route of vehicles, we consider the collection time in sewage store of village, distance between sewage store of villages and vehicle information as average velocity of vehicle, operation time of vehicle driver. We also develop the SCMS(Sludge Collection Management System) based on windows system with real data which is used in certain circumstance. And we experiment to figure out vehicle route and transportation cost throughout changing input data.

  • PDF

Garbage Collection Technique for Reduction of Migration Overhead and Lifetime Prolongment of NAND Flash Memory (낸드 플래시 메모리의 이주 오버헤드 감소 및 수명연장을 위한 가비지 컬렉션 기법)

  • Hwang, Sang-Ho;Kwak, Jong Wook
    • IEMEK Journal of Embedded Systems and Applications
    • /
    • v.11 no.2
    • /
    • pp.125-134
    • /
    • 2016
  • NAND flash memory has unique characteristics like as 'out-place-update' and limited lifetime compared with traditional storage systems. According to out-of-place update scheme, a number of invalid (or called dead) pages can be generated. In this case, garbage collection is needed to reclaim invalid pages. Because garbage collection results in not only erase operations but also copy operations of valid (or called live) pages to other blocks, many garbage collection techniques have proposed to reduce the overhead and to increase the lifetime of NAND Flash systems. This techniques sometimes select victim blocks including cold data for the wear leveling. However, most of them overlook the cost of selecting victim blocks including cold data. In this paper, we propose a garbage collection technique named CAPi (Cost Age with Proportion of invalid pages). Considering the additional overhead of what to select victim blocks including cold data, CAPi improves the response time in garbage collection and increase the lifetime in memory systems. Additionally, the proposed scheme also improves the efficiency of garbage collection by separating cold data from hot data in valid pages. In experimental evaluation, we showed that CAPi yields up to, at maximum, 73% improvement in lifetime compared with existing garbage collections.