• Title/Summary/Keyword: FRAGMENTATION

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Data Fragmentation Protection Technique for the Performance Enhancement of DB-Based Navigation Supporting Incremental Map Update (점증적인 맵 갱신을 지원하는 DB 기반 내비게이션의 성능 향상을 위한 데이터 단편화 방지 기법)

  • Kim, Yong Ho;Kim, Jae Kwang;Jin, Seongil
    • KIPS Transactions on Software and Data Engineering
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    • v.9 no.3
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    • pp.77-82
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    • 2020
  • Most of the navigation in the vehicle has been developed based on a complex structure of PSF(Physical Storage Format) files, making it difficult to support incremental map updates. DB-based navigation is drawing attention as a next-generation navigation method to solve this problem. In DB-based navigation that supports incremental map updates, data fragmentation due to continuous map data updates can increase data access costs, which can lead to a decrease in search performance. In this paper, as one of the performance enhancement methods of DB-based navigation that supports incremental map updates, data fragmentation prevention techniques were presented and the performance improvement effect was verified through actual implementation.

Monitoring of Deforestation and Fragmentation in Sarawak, Malaysia between 1990 and 2009 Using Landsat and SPOT Images

  • Kamlun, Kamlisa Uni;Goh, Mia How;Teo, Stephen;Tsuyuki, Satoshi;Phua, Mui-How
    • Journal of Forest and Environmental Science
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    • v.28 no.3
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    • pp.152-157
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    • 2012
  • Sarawak is the largest state in Malaysia that covers 37.5% of the total land area. Multitemporal satellite images of Landsat and SPOT were used to examine deforestation and forest fragmentation in Sarawak between 1990 and 2009. Supervised classification with maximum likelihood classifier was used to classify the land cover types in Sarawak. The overall accuracies of all classifications were more than 80%. Our results showed that forests were reduced at 0.62% annually during the two decades. The peat swamp forest suffered a tremendous loss of almost 50% between 1990 and 2009 especially at coastal divisions due to intensified oil palm plantation development. Fragmentation analysis revealed the loss of about 65% of the core area of intact forest during the change period. The core area of peat swamp forest had almost completely disappeared during the two decades.

L-shaped Submesh Allocation Scheme for Mesh-Connected Multicomputers (메쉬 멀티컴퓨터에서 L-모양 서브메쉬 할당기법)

  • 서경희;김성천
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.1
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    • pp.1-11
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    • 2003
  • Fragmentation is the main performance bottleneck of large, multi-user multicomputer system. This paper presents an L-Shaped Submesh Allocation(LSSA) strategy, which lifts the restriction on the rectangular shape formed by allocated processors in order to address the problem of fragmentation. LSSA can manipulate the shape of the required submesh to fit into the fragmented mesh system. Thus, LSSA accommodates incoming jobs faster than other strategies and results in the reduction of job response time. Extensive simulations show that LSSA performs more efficiently than other strategies in terms of the external fragmentation, the job response time and the system utilization.

Studies on the Regulation of Ovarian Granulosa Cell Apoptosis by Gonadotropins and Nitric Oxide (생식소 자극 호르몬과 Nitric Oxide에 의한 난소 과립세포의 Apoptosis 조절에 대한 연구)

  • 이석자
    • Development and Reproduction
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    • v.1 no.2
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    • pp.157-164
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    • 1997
  • To study the regulation of porcine follicular cell apostosis by gonadotropin, steroid, and nitric oxide, we analyzed DNA fragmentation, the hallmark of apoptosis, and nitrite production of porcine granulosa cells. Dissected indiidual follicles from ovary were separated in size (small, 2-3 mm; medium, 5-6 mm; large, 7-8 mm) and isolated granulosa cells were classified morpholocally as atretic or nonatretic. Nitrite concentration was measured by mixing follicular fluids with an equal volume of Griess reagent. Follicular nitric oxide (NO) concentration of healthy follicles was higher than that of atretic follicles. Apoptotic DNA fragmentation was suppressed in non-apoptotic granulosa cells. Follicular apoptosis was induced by androgen but prevented by gonadotropin in vitro. Apoptosis was confined to the granulosa cells. But it was not clear whether apoptosis of granulosa cells were isolated, incubated with or without gonadotropin, androgen and sodium nitroprusside (SNP), respectively at $37^{\circ}C$ for 24 hrs. Cultured granulosa cells were used to extract genomic DNA and culture media was asssayed for nitrite concentration. Nitrite production of culture media was increased, while apoptotic DNA fragmentation was suppressed in PMSG, hCG, testosterone+SNP and SNP treated groups. Nitrite concentration in culture media was decreased, but apoptotic DNA fragmentation was induced in testosterone treated group. These data suggest that NO production and apoptosis may be involved of granulosa cell apoptosis induced by testosterone.

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Microfailure Mechanisms of Single-Fiber Composites Using Tensile/Compressive Fragmentation Techniques and Acoustic Emission (인장/압축 Fragmentation시험법과 음향방출을 이용한 단 섬유 복합재료의 미세파괴 메커니즘)

  • 김진원;박종만;윤동진
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2000.04a
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    • pp.159-162
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    • 2000
  • Interfacial and microfailure properties of carbon fiber/epoxy matrix composites were evaluated using both tensile fragmentation and compressive Broutman tests with acoustic emission (AE). Amino-silane and maleic anhydride polymeric coupling agents were used via the dipping and electrodeposition (ED), respectively. Both coupling agents exhibited higher improvements in interfacial shear strength (IFSS) under tensile tests than compressive cases. However, ED treatment showed higher IFSS improvement than dipping case under both tensile and compressive test. The typical microfailure modes including fiber break, matrix cracking, and interlayer failure were observed during tensile test, whereas the diagonal slippage in fiber ends was observed during compressive test. For both the untreated and treated cases AE distributions were separated well under tensile testing. On the other hand, AE distributions were rather closer under compressive tests because of the difference in failure energies between tensile and compressive loading. Under both loading conditions, fiber breaks occurred around just before and after yielding point. Maximum AE voltage fur the waveform of carbon or basalt fiber breakage under tensile tests exhibited much larger than those under compressive tests.

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Comparison between Source-induced Dissociation and Collision-induced Dissociation of Ampicillin, Chloramphenicol, Ciprofloxacin, and Oxytetracycline via Mass Spectrometry

  • Lee, Seung Ha;Choi, Dal Woong
    • Toxicological Research
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    • v.29 no.2
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    • pp.107-114
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    • 2013
  • Mass spectrometry (MS) is a very powerful instrument that can be used to analyze a wide range of materials such as proteins, peptides, DNA, drugs, and polymers. The process typically involves either chemical or electron (impact) ionization of the analyte. The resulting charged species or fragment is subsequently identified by the detector. Usually, single mass uses source-induced dissociation (SID), whereas mass/mass uses collision-induced dissociation (CID) to analyze the chemical fragmentations Each technique has its own advantages and disadvantages. While CID is most effective for the analysis of pure substances, multiple-step MS is a powerful technique to get structural data. Analysis of veterinary drugs ampicillin, chloramphenicol, ciprofloxacin, and oxytetracycline serves to highlight the slight differences between SID and CID. For example, minor differences were observed between ciprofloxacin and oxytetracycline via SID or CID. However, distinct fragmentation patterns were observed for ampicllin depending on the analysis method. Both SID and CID showed similar fragmentation spectra but different signal intensities for chloramphenicol. There are several factors that can influence the fragmentation spectra, such as the collision energy, major precursor ion, electrospray mode (positive or negative), and sample homogeneity. Therefore, one must select a fragmentation method on an empirical and case-by-case basis.

Comparison of urban forest fragmentation between four cities in Kyungpook, Korea (경상북도 4개 도시의 녹지파편화 현상 비교)

  • Jang, Gab Sue;Park, In Hwan
    • Journal of Environmental Impact Assessment
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    • v.8 no.4
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    • pp.13-23
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    • 1999
  • This study was carried out to investigate the degree of impact from road construction and forest fragmentation after urbanization. And this study was also conducted to compare the urban forest fragmentations of four cities, Taegu, Pohang, Kyungju, and Kumi, in Kyungpook, Korea, with referring the Landsat TM remotely sensed data. Taegu metropolitan city has the largest forest volume of our surveying sites, comparing with three other cities-Kyungju Pohang Kumi city in kyungpook, Korea. The forest has been fragmented during urbanization, the number of forest patch has been increased, therefore, the patch size has been smaller. The forest in Pohang and Kyungju city represented the intermediate aspect between Taegu Metropolitan city and Kumi city, it means forest of the region has been stable condition. Road construction brings to increasing edge habitat area. However, as the core area was decreased, the habitats have been unstable. This result can be a basis on the management of the forest which is the origin of biodiversity. Hereafter, if the research, based on the multi-temporal remote sensing data, is proceeded continuously, the forest fragmentation will be able to be reduced. We will be able to settle urban forest management more practically.

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Analysis of In-situ Rock Conditions for Fragmentation Prediction in Bench Blasting (벤치발파에서 파쇄도 예측을 위한 암반조건 분석)

  • 최용근;이정인;이정상;김장순
    • Tunnel and Underground Space
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    • v.14 no.5
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    • pp.353-362
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    • 2004
  • Prediction of fragmentation in bench blasting is one of the most important factors to establish the production plan. It is widely accepted that fragmentation could be accurately predicted using the Kuz-Ram model in bench blasting. Nevertheless, the model has an ambiguous or subjective aspect in evaluating the model parameters such as joint condition, rock strength, density, burden, explosive strength and spacing. This study proposes a new method to evaluate the parameters of Kuz-Ram model, and the predicted mean fragment sizes using the proposed method are examined by comparing the measured sizes in the field. The results show that the predictions using Kuz-Ram model with the proposed method coincide with field measurements, but Kuz-Ram model does not reflect the in-situ rock condition and hence needs to be improved.

Feasibility of Forest Land Conversion to Other Use by Considering Forest Fragmentation (산지전용타당성조사제도에서 산림파편화지수의 고려방안 연구)

  • Kim, Mina;Choi, Jaeyong;Lee, Sanghyuk
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.16 no.4
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    • pp.53-63
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    • 2013
  • The purpose of this study is to analyze impacts of the forest fragmentation caused by development project. Furthermore, to investigate the applicability of landscape indicator when 'Feasibility of forest land conversion to other use' is conducted. The study site was consisted of golf course development and road construction. It is to compare before and after impacts of areal and linear development. As for the methods, selecting landscape indices, clustered into 3 Categories have been utilized. Category I was concerned with 'size of forest patches', II as 'shape of forest patches', and III as 'Core Area' These were calculated by FRAGSTATS, the program for analyzing fragmentation. The results showed that linear development caused more fragmented than areal development projects. Also, patch size, patch shape and core area are related to impacts of development, while Patch size decreased, patch shape and core area increased after development. Therefore, it is necessary to minimize the impacts of forest by considering fragmentation when development project is planned.

A Case Study on the Prediction of Fragmentation of Blasted Rock in Tunnel Blasting (터널발파에서 파쇄암의 입도예측에 관한 사례연구)

  • Ahn, Myung-Seog;Ryu, Chang-Ha;Kim, Su-Seog
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.3 no.1
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    • pp.3-9
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    • 2001
  • The investigation of the fragmentation of blasted rocks is particularly important because it is a measure of the blast efficiency. The degree of fragmentation has a major effect on the efficiency of the loading and crushing operations. Getting such an information on the large pile of blasted rock is not an easy operation. This paper presents the results of case study to evaluate the performance of two types of tunnel blasting: V-cut and burn cut. The digital images of muckpiles were analyzed to produce size distribution and it was compared with those of predictive equations.

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