• Journal of Life Science
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• v.15 no.2 s.69
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• pp.202-210
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• 2005

Following ingestion, Salmonella must adhere to and colonize the intestinal epithelium of the host in order to establish infection. S. typhimurium synthesize several appendages that are believed to mediate attachment. These include type 1 fimbriae, plasmid-encoded (PE) fimbriae, long polar (LP) fimbriae, and thin aggregative fimbriae. However, the precise roles of these putative adhesins remain unclear, due to conflicting data in the literature. We constructed strains lacking four different fimbriae including type 1 fimbriae, PE fimbriae, LP fimbriae, and thin aggregative fimbriae, as well as strains lacking each fimbriae alone. In cell culture adhesion assays, these mutants adhered to several mammalian cell lines as well as wild-type S. typhimurium. These strains were also screened for virulence in mice, and all strains were virulent or nearly as virulent as their wild-type parents. In contrast, When a strain lacking four fimbriae was screened for virulence in chicks, it was found to be highly attenuated. This suggests a role for either type 1 fimbriae, PE fimbriae, LP fimbriae or thin aggregative fimbriae or a combination of thease fimbriae in the colonization of chicks. It also suggests that differences exist with respect to the surface structures that mediate attachment of Salmonella in chicks as compared with mice.

• Journal of Aquaculture
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• v.13 no.2
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• pp.153-161
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• 2000

Growth trends of 10 selected species of benthic diatoms, considered essential dietary requirement of the newly settled abalone were monitored. Navicula sp. (B-38), N. incerta and Caloneis schroderi, grew faster than the other tested diatoms. 16 and 32 % abalones fed on Raphoneis sp. and Phaeodactylum settled, respectively; less abalones souled, when fed on Navicula sp., Hantzxchia marina or Nitzschia sp. In the first experiment, survival of the settled abalone was the highest (63 %) and lowest (31 %) for those fed on Rhaphoneis sp. and Navicular sp. respectively. However, in the second and third series of esperiments, abalones fed on Rhaphoneis sp. and Navicula sp. showed the highest (67, 49 %) and lowest (35, 18 %) survival. C. schroderi proved to be the best diet, as the shell length of those fed on the diatoms was 83 ${\mu}$m, as against about 36 ${\mu}$m of those abalones, receiving H. marina or Nitzschia sp., diatoms of the lowest dietary value.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.157-160
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• 2002

This study was carried out to the harvesting efficiency of equipment used fer harvesting of rhizomes of Saururus chinensis Bail. Labor-saving efficiency showed 60-67% enhancement by using tillage operations with power tiller, digger attached to power tiller, and digger attached to tractor compared with manual harvest. Loss percentage of rhizomes by harvesting equipments was 2.2-8.8% lower than by manual harvest. Fresh rhizome yield and income index were increased 3-10% and 13-27% respectively by harvesting equipments, showing the highest yield and index in digger attached to tractor, Thus, digger attached to tractor showed the most effective harvest equipment for Saururus chinensis rhizome.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.4
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• pp.305-311
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• 2005

Shotcrete adhesive strength in large section tunnels in jointed rock masses plays an important role in preventing rock block from falling and shotcrete debonding due to blasting vibration. Nevertheless, it has not been considered as a major factor such as shotcrete compressive strength in design and construction. For this reason, the purpose of this study is to analyze the effect on shotcrete adhesive strength for large-sectioned tunnels. First, the parametric study using numerical model similar to Holmgren's punch-loaded test was executed for various range of adhesive strength. It shows that the shotcrete bearing capacity is linearly proportioned to the adhesive strength between shotcrete layer and blocks. And then, distinct element analysis of a jointed rock tunnel for an adhesive strength of 1 MPa and a conventional fully-bonded condition between the shotcrete layer and the excavation face was compared in order to evaluate the effect of the shotcrete adhesive strength.

• Membrane Journal
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• v.11 no.1
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• pp.29-37
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• 2001

본 논문은 인공 진피와 조직공학용 scaffold로 이용하기 위해 다공성 membrane로서 gelatin-based sponge의 효율성을 연구하였다. 불용성의 다공성 membrane은 1-ethyl-(3-3dimethylaminopropyl)carbodiimide(EDC)로 가교하여 제조하였다. Fourier-transformed infrared (FT-IR) spectroscopy, scanning electron microscopy(SEM) 그리고 Instron analysis로 다공성 membrane의 특성을 조사하였다. 다공성 membrane은 용적당 큰 표면적을 제공하는 micro porous한 구조를 가지고 있다. Gelatin/hyaluronic acid (HA) membrane의 공경크기는 40~200$\mu\textrm{m}$이다. HA의 첨가는 다공성 membrane의 기계적 강도와 세포부착능력에 영향을 미쳤다. Gelatin/HA 다공성 membrane의 압축강도는 collagen과 비슷하며, 세포배양과 인공진피 transplantation에 있어서의 충분한 기계적 강도를 가지고 있다. Fibroblasts를 함유한 진피기질을 제조하기 위해 직경 8mm의 다공성 membran에 4$\times$10(sup)5cells/membrane의 세포밀도로 fibroblast를 배양하였다. GH91 porous membrane에서의 fibroblast 부착성은 GH55 porous membrane에서보다 우수하였다. 삼차원 구조의 gelatin/HA membrane matrix에서의 fibroblast의 배양은 생체내 조건과 유사한 생리적 환경을 제공하였다.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.44-52
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• 1996

Sensory properties of cooked rice were affected by the varieties and growing environments of the rice. Moistness, cohesiveness, and adhesiveness of cooked rice were highly and positively correlated each other, whereas firmness was negatively correlated with these attributes. Sixty rice samples which differed in varieties and/or growing environments were divided into four groups based on their textural properties through principal component analysis and cluster analysis. Quality type I showed the highest values for moistness, cohesiveness, and adhesiveness, and the lowest values for firmness of cooked rice. On the other hand, quality type IV showed just the opposite values. There was no significant difference among rice starches in amylose content (P<0.05). A17 (type III) and A09 (type IV) had higher blue values for starch and amylopectin than the other samples (type I and II). On the amylogram, these samples showed lower values for breakdown and higher values for setback than the other samples. Average degree of polymerization, average chain length, and average number of chains for amylose and amylopectin were 597-878 and 2660-3140, 140-230 and 17-19, and 3.1-4.9 and 140-170, respectively.

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.242-247
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• 2005

통신전주는 케이블을 가공에 설치하거나 가입자 댁내로 인입시키기 위해 케이블을 지지하는 옥외 시설물로서 케이블을 쉽고 경제적으로 포설할 수 있는 장점이 있어 통신망 구축에 널리 사용되어 왔으며 특히 최근에는 FTTH(유사 FTTH 포함) 구축이 활발히 진행됨에 따라 전주에 부착물을 취부하는 경우가 많아지고 있어 통신전주의 활용도가 한층 더 높아지고 있는 상황이다. 그러나 최근 태풍 "매미" 등 극심한 기상환경 변화로 인해 통신시설물의 피해를 초래하고 있어 통신시설물의 풍하중에 대한 규정을 강화하고 있는 추세에 전주에 추가 부착물 취부에 따른 풍하중에 대한 전주의 안전 문제가 제기됨에 따라 전주의 안전성 검토가 절실히 요구되어 있는 실정이다. 따라서, 본 논문에서는 부착물이 취부되는 통신전주의 풍하중에 대한 안전성 검토 방법을 제시하고 나아가 안전한 전주가 되도록 보강할 수 있는 전주 보강기술을 소개하고자 한다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.150-159
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• 2019

The bond analysis model equation was proposed through the regression analysis of the experimental values of bond behavior for each rebar. In order to verify the appropriateness of the bond analysis model equation, the bond behaviors calculated by the proposed bond analysis model, BPE model and CMR model were compared with experimental values. The proposed bond model showed the closest behavior to the experimental values when compared to other analysis models. The former models can not consider the different properties of GFRP rebar according to composed materials, mixing and manufacturing method and the latter has limitation to express the relationships between bond behavior because of derived formula by numerical analysis. This study proposed the analytical model different considering bond mechanism according to surface type. In order to verity the appropriateness of the bond analytical model, the bond behaviors calculated by the proposed bond analytical model, BPE model and CMR model were compared with experimental values. The proposed bond model showed the closest behavior to the experimental values when compared to other analysis models.

• Annual Conference on Human and Language Technology
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• 2012.10a
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• pp.126-131
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• 2012

본 논문은 자연언어처리에 필요한 여러 언어 정보를 구축하기 위한 도구를 설계하고 구현하였다. 본 논문에서 제안한 부착 도구는 기본적으로 형태소, 구묶음, 기반구의 품사 정보를 부착하고 추가적으로 명사에 대해서는 각 요소의 의미정보를 부착한다. 또한 형태소와 구묶음의 경우에는 사전형 정보를 부착함으로써 사전 구축 등 보다 폭넓게 사용될 수 있도록 하였다. 언어정보 부착에 있어서 가장 어려운 점은 어떻게 여러 작업자들이 일관성을 유지하느냐이다. 이를 위해 본 논문에서는 각 작업자들이 다른 작업자들의 부착 결과를 쉽게 참조하여 보다 손쉽게 수정할 수 있도록 설계되었다. 또한 기존에 잘못 부착된 정보를 발견하면 이를 쉽게 고칠 수 있도록 하였으며 또한 유사한 오류를 검색할 수 있도록 하여 쉽게 수정할 수 있도록 하였다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.6
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• pp.785-795
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• 2018

The International Maritime Organization (IMO) has recognized the risk of hull fouling and announced '2011 Guidelines for the control and management of ship's biofouling to minimize the transfer of invasive aquatic species'and is planning international regulations to enforce them in the future. In this study, to effectively respond to future international regulation, we introduce the case of leading countries related to management of hull fouling and also investigate environmental risk assessment techniques for in-water cleaning. Australia and New Zealand, the leading countries in hull fouling management, have established hull fouling regulations through biological and chemical risk assessment based on in-water cleaning scenarios. Most European countries without their government regulation have been found to perform in-water cleaning in accordance with the IMO's hull fouling regulations. In the Republic of Korea, there is no domestic law for hull fouling organisms, and only approximately 17 species of marine ecological disturbance organisms, are designated and managed under the Marine Ecosystem Law. Since in-water cleaning is accompanied by diffusion of alien species and release of chemical substances into aquatic environments, results from biological as well as chemical risk assessment are performed separately, and then evaluation of in-water cleaning permission is judged by combining these two results. Biological risk assessment created 40 codes of in-water cleaning scenarios, and calculated Risk Priority Number (RPN) scores based on key factors that affect intrusion of alien species during in-water cleaning. Chemical risk assessment was performed using the MAMPEC (Marine Antifoulant Model to Predict Environmental Concentrations), to determine PEC and PNEC values based on copper concentration released during in-water cleaning. Finally, if the PEC/PNEC ratio is >1, it means that chemical risk is high. Based on the assumption that the R/V EARDO ship performs in-water cleaning at Busan's Gamcheon Port, biological risk was estimated to be low due to the RPN value was <10,000, but the PEC/PNEC ratio was higher than 1, it was evaluated as impossible for in-water cleaning. Therefore, it will be necessary for the Republic of Korea to develop the in-water cleaning technology by referring to the case of leading countries and to establish domestic law of ship's hull fouling management, suitable for domestic harbors.