• 대한전자공학회논문지TC
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• 제42권12호
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• pp.149-158
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• 2005

본 논문은 고정대역 네트워크에서 최대 TCP 혼잡윈도우를 제한하여, 버퍼 크기와 무관하게 안정적인 성능과 전송률을 제공할 수 있는 혼잡회피 알고리즘을 제안한다. 현재는 AIMD(Additive Increase, Multiplicative Decrease) 기반의 혼잡제어 방법이 가장 널리 사용되고 있다. 그러나 AIMD 기반의 TCP 혼잡제어 방법은 고정대역 네트워크에서 불필요하게 성능을 저하시키는 문제가 있다는 것이 여러 연구결과를 통해 알려져 있다. 또한 TCP의 톱니파형 데이터율로 안정적인 데이터 전송률이 필요한 응용에 적용하기 어렵다. 제안된 알고리즘은 필요에 따라 공평성을 유지하며 혼잡에 의한 손실을 방지하기 위해 혼잡윈도우의 크기를 제한한다. 최대 혼잡윈도우의 크기를 병목노드에서 데이터 축적을 방지하는 지연 정보로 결정하여, 별도의 버퍼와 윈도우 제어절차 없이 연결의 성능과 전송율이 안정적이도록 한다. 다양한 경우에 대한 시뮬레이션을 통해 호환성, 정상상태의 성능, 정상상태 손실 패킷 수, 그리고 혼잡윈도우의 분산 등으로 특성을 검증하였다. 제안된 방법은 송신단의 간단한 수정으로 적용이 가능하며, 네트워크 라우터와 사용자 프로그램의 수정이 불필요하여 확산이 용이한 장점을 가지며, 고정대역 네트워크로 볼 수 있는 국내 초고속인터넷 접속망에 적용하면 성능개선을 얻을 수 있다.

• Journal of Microbiology and Biotechnology
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• 제27권2호
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• pp.321-334
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• 2017

Process surveillance within agricultural biogas plants (BGPs) was concurrently studied by high-throughput 16S rRNA gene amplicon sequencing and an optimized quantitative microscopic fingerprinting (QMF) technique. In contrast to 16S rRNA gene amplicons, digitalized microscopy is a rapid and cost-effective method that facilitates enumeration and morphological differentiation of the most significant groups of methanogens regarding their shape and characteristic autofluorescent factor 420. Moreover, the fluorescence signal mirrors cell vitality. In this study, four different BGPs were investigated. The results indicated stable process performance in the mesophilic BGPs and in the thermophilic reactor. Bacterial subcommunity characterization revealed significant differences between the four BGPs. Most remarkably, the genera Defluviitoga and Halocella dominated the thermophilic bacterial subcommunity, whereas members of another taxon, Syntrophaceticus, were found to be abundant in the mesophilic BGP. The domain Archaea was dominated by the genus Methanoculleus in all four BGPs, followed by Methanosaeta in BGP1 and BGP3. In contrast, Methanothermobacter members were highly abundant in the thermophilic BGP4. Furthermore, a high consistency between the sequencing approach and the QMF method was shown, especially for the thermophilic BGP. The differences elucidated that using this biphasic approach for mesophilic BGPs provided novel insights regarding disaggregated single cells of Methanosarcina and Methanosaeta species. Both dominated the archaeal subcommunity and replaced coccoid Methanoculleus members belonging to the same group of Methanomicrobiales that have been frequently observed in similar BGPs. This work demonstrates that combining QMF and 16S rRNA gene amplicon sequencing is a complementary strategy to describe archaeal community structures within biogas processes.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.135-138
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• 2000

This paper is intended to propose what manufacturing configuration (manufacturing planning and shop floor control) is suitable for the tire industry. Basically tire-manufacturing process is mixed-products, parallel-disconnected-flow-shop. Both throughput time and cycle tine are very short, the variety of tires is very high, the setup time is long, shop floor data reporting requirements is high, and there are many equipments and people working. And with no exception, tire industry also now confronts increasing requirements of delivery conformance with the above peculiar characteristics of tire manufacturing and changing market environments, this paper suggests, weekly master scheduling with no MRP is desirable and traditional kanban is right selection for shop floor control/scheduling. This paper describes why this configuration should be, using the manufacturing engineering principles and some new insights like four primitives of parallel flow shop. Generally known that shop with high parallel-product-mix and long setup time isn't good candidate for kanban. The four primitives of parallel flow shop explain why kanban is also useful scheduling technique in that environment.

• The Plant Pathology Journal
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• 제24권1호
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• pp.1-7
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• 2008

Fusarium verticillioides (teleomorph Gibberella moniliformis) is associated with maize worldwide causing ear rot and stalk rot, and produces fumonisins, a group of mycotoxins detrimental to humans and animals. While research tools are available, our understanding of the molecular mechanisms associated with fungal virulence and fumonisin biosynthesis in F. verticillioides is still limited. One of the restraints that hampers F. verticillioides gene characterization is the fact that homologous recombination (HR) frequency is very low (<2%). Screening for a true gene knock-out mutant is a laborious process due to a high number of ectopic integrations. In this study, we generated a F. verticillioides mutant (SF41) deleted for FvKU70, a gene directly responsible for non-homologous end-joining mechanism, with the aim of improving HR frequency. Here, we demonstrate that FvKU70 deletion does not impact key Fverticillioides phenotypes, e.g., development, secondary metabolism, and virulence, while dramatically improving HR frequency. Significantly, we also confirmed that a high percentage (>85%) of the HR mutant strains harbor a desired mutation with no additional copy of the mutant allele inserted in the genome. We conclude that SF41 is suitable for use as a type strain when performing high-throughput gene function studies in F. verticillioides.

• Animal Bioscience
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• 제34권9호
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• pp.1466-1478
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• 2021

Objective: Ruminants are completely dependent on their microbiota for rumen fermentation, feed digestion, and consequently, their metabolism for productivity. This study aimed to evaluate the rumen bacteria of lactating yaks with different milk protein yields, using high-throughput sequencing technology, in order to understand the influence of these bacteria on milk production. Methods: Yaks with similar high milk protein yield (high milk yield and high milk protein content, HH; n = 12) and low milk protein yield (low milk yield and low milk protein content, LL; n = 12) were randomly selected from 57 mid-lactation yaks. Ruminal contents were collected using an oral stomach tube from the 24 yaks selected. High-throughput sequencing of bacterial 16S rRNA gene was used. Results: Ruminal ammonia N, total volatile fatty acids, acetate, propionate, and isobutyrate concentrations were found to be higher in HH than LL yaks. Community richness (Chao 1 index) and diversity indices (Shannon index) of rumen microbiota were higher in LL than HH yaks. Relative abundances of the Bacteroidetes and Tenericutes phyla in the rumen fluid were significantly increased in HH than LL yaks, but significantly decreased for Firmicutes. Relative abundances of the Succiniclasticum, Butyrivibrio 2, Prevotella 1, and Prevotellaceae UCG-001 genera in the rumen fluid of HH yaks was significantly increased, but significantly decreased for Christensenellaceae R-7 group and Coprococcus 1. Principal coordinates analysis on unweighted UniFrac distances revealed that the bacterial community structure of rumen differed between yaks with high and low milk protein yields. Furthermore, rumen microbiota were functionally enriched in relation to transporters, ABC transporters, ribosome, and urine metabolism, and also significantly altered in HH and LL yaks. Conclusion: We observed significant differences in the composition, diversity, fermentation product concentrations, and function of ruminal microorganisms between yaks with high and low milk protein yields, suggesting the potential influence of rumen microbiota on milk protein yield in yaks. A deeper understanding of this process may allow future modulation of the rumen microbiome for improved agricultural yield through bacterial community design.

• Genomics & Informatics
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• 제7권3호
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• pp.168-170
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• 2009

The explosion in biological data resulting from high-throughput experiments requires new software tools to manipulate and display pathways in a way that can integrate disparate sources of information. A visual Java-based CAD tool for drawing and annotating biological pathways with semiautomatic image-processing features is described in this paper. The result of the image-editing process is an XML file for the appropriate links. This tool integrates the pathway images and XML file sources. The system has facilities for linking graphical objects to external databases and is capable of reproducing existing visual representations of pathway maps.

• 대한의생명과학회지
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• 제10권2호
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• pp.75-84
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• 2004

Massive identification of differentially expressed patterns has been used as a tool to detect genes that are involved in disease related process. We employed circular single stranded sense molecules as probe DNA for a DNA chip. The circular single stranded DNAs derived from 1,152 unigene cDNA clones were purified in a high throughput mode from the culture supernatant of bacterial transformants containing recombinant phagemids and arrayed onto silanized slide glasses. The DNA chip was examined for its utility in detection of differential expression profile by using cDNA hybridization. Hybridization of the single stranded probe DNA were performed with Cy3- or Cy5-labeled target cDNA preparations at $60^\circ$C. Dot scanning performed with the hybridized slide showed 29 up-regulated and 6 down-regulated genes in a cancerous liver tissue when compared to those of adjacent noncancerous liver tissue. These results indicate that the circular single stranded sense molecules can be employed as probe DNA of arrays in order to obtain a precious panel of differentially expressed genes.

• Journal of Welding and Joining
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• 제34권1호
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• pp.35-40
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• 2016

Recent developments of Laser metal 3D deposition with wire feeding are reviewed which provide an alternative to powder feeding method. The wire feeding direction, angle and position as well as laser power, wire feeding rate, and deposition speed are found to be key parameters to make quality deposition with high throughput. When compared with the powder feed, the wire feed shows higher material efficiency, higher deposition rate, and smoother surface. Large elongated columnar grains which have epitaxial growth across deposit layers are observed in deposit cross sections. The growth direction is parallel to the thermal gradient during the deposit process. Tensile properties are found to be dependent on the direction due to the anisotropic deposit property. A real-time feedback control is demonstrated to be effective to improve the deposition stability.

• 한국통신학회논문지
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• 제19권6호
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• pp.1056-1063
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• 1994

본 논문에서는 연상 메모리 소자에 대한 데이터와의 병렬 처리 최적 정합 방식을 적용하여 계산 효율과 처리율을 높인 단일 PE 아키텍쳐를 이용하여 CAM을 설계하였다. 설계한 CAM은 크게 3개의 기능 블록(입력 MUX, 최적 정합 CAM, 제어부)으로 구성되어 있다. 데이터 처리는 병렬 입력 및 병렬 비교를 하여 고속으로 데이터를 처리하는 전.병렬 방식을 채택하였다. 이러한 특성을 갖는 CAM은 회로 및 논리 시뮬레이션을 통하여 ETRI 3 m-well 공정 설계 규칙을 사용하여 설계하였다. 본 논문에서 설계된 CAM의 최대 동작 주파수는 20MHz이다.

• 전자공학회논문지A
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• 제33A권7호
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• pp.55-63
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• 1996

In this paper, a multiple-access algorithm for PCN is proposed. The proposed algorithm provides th integrated service of information soruces and can be operated stably in high load state. Given bandwidth is efficiently used for it in the microcell environment. And system performance can be improved through the statistical-multiplexing technque. In order to process the speech signal usually requiring real-tiem processing, we adopt a random access of AlOHA type for th ebasic protocol sturcture and assume the form of ALOHA-reservation. We have analyzed the performance of the proposed algorithm through system throughput and packet delay in the microcell environment.