• Title/Summary/Keyword: Fragment size

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Forest Patch Characteristics and Their Contribution to Forest-Bird Diversity - Focus on Chungcheong Province Area - (산림패치의 특성이 조류 종 다양성에 미치는 영향분석 - 충청지역을 중심으로 -)

  • Lee, Dong-Kun;Park, Chan;Oh, Kyu-Sik
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.13 no.5
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    • pp.146-153
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    • 2010
  • Urban development typically results in many species being confined to small, isolated and degraded habitat fragments. Fragment size and isolation underpin many studies of modified landscape to prevent biodiversity loss. However, habitat characteristics such as vegetation structure and edge effects are less frequently incorporated in planning. The relative influence of biogeographic (e.g. size, isolation) and vegetation parameters on assemblages is poorly understood, but critical for conservation management. In this study, the relative importance of biogeographic and vegetation parameters in explaining the diversity of forest-interior dwelling birds in forest fragments in Chungcheong Province Area. Fragment size and vegetation characteristics were consistently important predictors of bird diversity. Forestinterior bird richness was influenced by fragment size (0.437), wood age (0.332), wood diameter (0.068), and patch shape (-0.079). To preserve bird diversity of Chungcheong Province Area, it is important to consider differing responses of bird diversity to landscape change, move beyond a focus primarily on spatial attributes (size, isolation) to recognize that landscape change also has profound effects on habitat composition and quality. The result is very useful for long-term aspect of biodiversity conservation plan in regional scale.

Fragmentation and energy absorption characteristics of Red, Berea and Buff sandstones based on different loading rates and water contents

  • Kim, Eunhye;Garcia, Adriana;Changani, Hossein
    • Geomechanics and Engineering
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    • v.14 no.2
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    • pp.151-159
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    • 2018
  • Annually, the global production of construction aggregates reaches over 40 billion tons, making aggregates the largest mining sector by volume and value. Currently, the aggregate industry is shifting from sand to hard rock as a result of legislation limiting the extraction of natural sands and gravels. A major implication of this change in the aggregate industry is the need for understanding rock fragmentation and energy absorption to produce more cost-effective aggregates. In this paper, we focused on incorporating dynamic rock and soil mechanics to understand the effects of loading rate and water saturation on the rock fragmentation and energy absorption of three different sandstones (Red, Berea and Buff) with different pore sizes. Rock core samples were prepared in accordance to the ASTM standards for compressive strength testing. Saturated and dry samples were subsequently prepared and fragmented via fast and dynamic compressive strength tests. The particle size distributions of the resulting fragments were subsequently analyzed using mechanical gradation tests. Our results indicate that the rock fragment size generally decreased with increasing loading rate and water content. In addition, the fragment sizes in the larger pore size sample (Buff sandstone) were relatively smaller those in the smaller pore size sample (Red sandstone). Notably, energy absorption decreased with increased loading rate, water content and rock pore size. These results support the conclusion that rock fragment size is positively correlated with the energy absorption of rocks. In addition, the rock fragment size increases as the energy absorption increases. Thus, our data provide insightful information for improving cost-effective aggregate production methods.

Optimal conditions for pigmentation in Bacillus licheniformis SSA3 and cloning of a DNA fragment involved in pigment production

  • Kim, Jong-Kyu;Shin, Ok-Sun
    • Journal of Microbiology and Biotechnology
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    • v.5 no.1
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    • pp.22-25
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    • 1995
  • Bacillus licheniformis SSA3 can produce a dark-brown antimutagenic pigment. The optimal conditions for production of this pigment are reached at 0.1% tyrosine, in pH 6-8, within 7-9 days, at $30^{\circ}C$, and in aerobic condition. We cloned a DNA fragment involved in pigment synthesis from Bacillus licheniformis SSA3 using a mutant strain. The cloned DNA was 7kb in size, which can produce the same pigment even in E. coli.

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HU Threshold Value for IV Catheter Fragment in Peripheral Vein of Volume Rendering 3D MDCT Imaging (정맥 내의 IV 카테터 조각을 3D MDCT 볼륨렌더링 영상으로 구현하기 위한 HU 임계치)

  • Jang, Keun-Jo;Kweon, Dae-Cheol
    • The Journal of the Korea Contents Association
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    • v.7 no.4
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    • pp.206-212
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    • 2007
  • To evaluate the HU value of the IV catheter fragment of CT on the accuracy and size in the peripheral vein. Pilot study of profile and table functions on PC by software was calculated of HU value of IV catheter fragment. This study demonstrates the utility of volume rendering technique to localize a small, subtle IV catheter, which can easily be reformatted of MDCT reformations. IV catheter fragment optimal image described as threshold range. Volume rendering of HU using a MDCT is an excellent method for evaluation the IV catheter fragment in three dimension.

RESTORATION OF A FRACTURED INCISOR USING ORIGINAL TOOTH FRAGMENT : A CASE REPORT (치아 파절편 재부착을 이용한 수복의 임상증례 보고)

  • Kim, Ji-Yeon;Park, Ki-Tae
    • Journal of the korean academy of Pediatric Dentistry
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    • v.24 no.2
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    • pp.475-483
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    • 1997
  • Fracture of the crown in a permanent incisor is relatively common. When it occurs with pulp exposure, it presents both restorative and endodontic problems. In the restoration of a fractured incisor, reattachment of the original fragment or restoration with a composite resin is preferred over a temporary crown. If fractured fragment is intact, the tooth can be restored with reattachment of the fragment. An exposed pulp in a young crown-fractured incisor is usually treated with either pulp capping or pulpotomy depending on the size of an exposure and time elapsed since injury. However, in teeth showing vital and/or hyperplastic pulp tissue at the exposure, only superficial layers of the pulp and surrounding dentin should be removed : i.e. partial pulpotomy can be performed in immature as well as mature teeth. This paper reports 2 cases of crown-fractured permanent incisors with pulp exposure that had been treated by reattachment of original fragment followed by partial pulpotomy or partial pulpectomy. The following results are obtained. ; 1. Fragment reattachment is an acceptable semi-permanent restoration of crown fractured young permanent incisor. 2. Partial pulpotomy is recommended as the treatment of choice in crown-fractured permanent teeth with pulp exposure.

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Molecular Genetic Mechanism of Aromatic Compound Biodegradation by soil Streptomycetes

  • Kim, Eumg-Soo
    • Proceedings of the Korean Society for Applied Microbiology Conference
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    • 2001.06a
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    • pp.118-119
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    • 2001
  • A Southern-hybridization analysis and size-selected DNA library screening led to the isolation of a 6.3-kbp S. setonii DNA fragment, from which the Cl20-encoding genetic locus was found to be located within a 1.4-kbp DNA fragment. A complete nucleotide sequencing analysis of the 1.4-kbp DNA fragment revealed a 0.84-kbp ORF, which showed a strong overall amino acid similarity to the known high-G+C gram-positive bacterial mesophilic C120s. The heterologous expression of the cloned 1.4-kbp DNA fragment in E. coli demonstrated that this Cl20 possessed a thermophilic activity within a broad temperature range and showed a higher activity against 3-methy1catechol than catechol or 4-methy-catechol, but no activity against protocatecuate.

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A Simple and Efficient Antialiasing Method with the RUF buffer (RUF 버퍼를 이용한 간단하고 효율적인 안티알리아싱 기법)

  • 김병욱;박우찬;양성봉;한탁돈
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.3_4
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    • pp.205-212
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    • 2003
  • In this paper, we propose a simple and efficient hardware-supported antialiasing algorithm and its rendering scheme. The proposed method can efficiently reduce the required memory bandwidth as well as memory size compared to a conventional supersampling when rendering 3D models. In addition, it can provide almost the same high quality scenes as supersampling does. In this paper, we have introduced the RUF (Recently Used Fragment) buffer that stores some or whole parts of a fragment or two more the merged results of fragments that recently used in color calculation. We have also proposed a color calculation algorithm to deteriorate the image quality as referencing the RUF buffer. Because of the efficiency presented in the proposed algorithm, the more number of sampling points increases the more memory saving ratio we can gain relative to the conventional supersampling. In our simulation, the proposed method can reduce the amount of memory size by 31% and the memory bandwidth by 11% with a moderate pixel color difference of 1.3% compared to supersampling for 8 sparse sampling points.

Techniques of XML Fragment Stream Organization for Efficient XML Query Processing in Mobile Clients (이동 클라이언트에서 효율적인 XML 질의 처리를 위한 XML 조각 스트림 구성 기법)

  • Ryu, Jeong-Hoon;Kang, Hyun-Chul
    • The Journal of Society for e-Business Studies
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    • v.14 no.4
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    • pp.75-94
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    • 2009
  • Since XML emerged as a standard for data exchange on the web, it has been established as a core component in e-Commerce and efficient query processing over XML data in ubiquitous computing environment has been also receiving much attention. Recently, the techniques were proposed whereby an XML document is fragmented into XML fragments to be streamed and the mobile clients receive the stream while processing queries over it. In processing queries over an XML fragment stream, the average access time significantly depends on the order of fragments in the stream. As such, for query performance, an efficient organization of XML fragment stream is required as well as the indexing for energy-efficient query processing due to the reduction of tuning time. In this paper, a technique of XML fragment stream organization based on query frequencies, fragment size, fragment access frequencies, and an active XML-based indexing scheme are proposed. Through implementation and performance experiments, our techniques were shown to be efficient compared with the conventional XML fragment stream organizations.

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Isolation, Restriction Mapping, and Promoter Sequence Analysis of an Isoperoxidase Gene from Korean-Radish, Raphanus sativus L.

  • Park, Jong-Hoon;Kim, Soung-Soo
    • BMB Reports
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    • v.29 no.1
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    • pp.52-57
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    • 1996
  • A specific DNA fragment from Korean radish (Raphanus sativus L.) was amplified by performing PCR with oligonucleotide primers which correspond to the highly conserved regions of plant peroxidases. The size of the PCR product was ca. 400 bp, as expected from the known plant peroxidase genes. Comparison of the nucleotide and deduced amino acid sequences of the PCR product to those of other plant peroxidase-encoding genes revealed that the amplified fragment corresponded to the highly conserved region I and III of plant peroxidases. By screening a genomic library of Korean radish using the amplified fragment as a probe, two positive clones, named prxK1 and prxK2, were isolated. Restriction mapping studies indicated that the 5.2 kb Sail fragment of the prxK1 clone and the 4.0 kb EcoRI fragment of the prxK2 clone encode separate isoperoxidase genes. Analyses of the promoter region of the prxK1 clone shows that putative CAAT box, CMT box, and TGA1b binding sequence (5' TGACGT) are present 718 bp upstream from the start codon.

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Cloning and Characterization of the $_L$-Lactate Dehydrogenase Gene (IdhL) from Lactobacillus reuteri ATCC 55739

  • Park, Jar-Yong;Park, Sun-Jung;Nam, Su-Jin;Ha, Yeong-Lae;Kim, Jeong-Hwan
    • Journal of Microbiology and Biotechnology
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    • v.12 no.5
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    • pp.716-721
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    • 2002
  • The ldhL gene encoding the $_L$-(+) lactate dehydrogenase was cloned from Lactobacillus reuteri ATCC 55739 chromosomal DNA and characterized. An internal 750-bp fiagment of ldhL gene was amplified by PCR using primers based on the conserved region of lactobacilli ldhL genes. A genomic library off. reuteri ATCC 55739 was constructed using pBR322, and colony hybridization experiments were performed using the 750-bp fragment as aprobe. One clone harboring a 4.0-kb PstI fragment was identified, and nucleotide sequencing confirmed it as an open reading frame of 972 bp in size in the middle. In addition to IdhL gene, an ORF homologous to Streptococcus pneumoniae TIGR4 hydrolase gene and 3' part of phosphomevalonate kinase gene (mvaK2) were also found on the 4 kb fragment. $_L$-LDH of L. reuteri ATCC 55739 showed the highest degree of homology with the $_L$-LDH of Pediococcus acidilactici (62.4%), fullowed by the $_L$-LDH of Lactobacillus pentosus (58.7%). The size of IdhL transcript determined by Northern blot was 1 kb, indicating the monocistronic nature of IdhL.