• Korean Journal of Environment and Ecology
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• v.30 no.1
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• pp.81-91
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• 2016

This study was performed to investigate and monitor changes in aquatic ecological communities, particularly benthic macroinvertebrates from the upper reaches to the down reaches of Songchu valley before the project of Songchu valley translocation initiates. We aimed to verify the translocation effects of the valley on the aquatic macroinvertebrate communities. A field investigation was conducted over three rounds from November 2012 to August 2013. A total of four sites were selected: one to represent the control site (St. 1), two for the translocation sites (St. 2, 3), and one for the downstream sites (St. 4). Our quantitative sampling revealed that the total number of benthic macroinvertebrates were 3,805, which belong to 62 species, 32 families, 9 orders, 5 classes and 4 phyla. As a result of the community analysis at the control site, dominant index was 0.52(${\pm}0.16$), diversity index was 1.95(${\pm}0.44$), evenness index was 0.81(${\pm}0.04$), and richness index was 2.25(${\pm}0.85$). Thus, the community structure was found to be relatively stable. For the EPT ratio of species and individuals that appeared, the control site showed the highest values at 67.60(${\pm}5.66$)% and 66.30(${\pm}2.06$)% respectively, but its value became lower towards the downstream sites. Upon the statistical analysis of the functional feeding groups, it was found that gathering-collectors and filtering-collectors increased toward the downstream sites while shredders decreased. From the point of habitat-oriented group evaluation, sprawlers decreased and burrows increased toward the downstream sites. According to the analysis using Korea Saprobic Index (KSI), the control site is categorized as grade A with average value at 0.75(${\pm}0.10$). However, the grade gradually falls from A to B toward the lower reaches, as the KSI value increases at the translocation and downstream sites.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1994.04a
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• pp.10-15
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• 1994

전기도금 공정에서 발생하는 수소취성은 다량의 수소이온이 강제품에 흡수되어 취화되는 현상을 나타내는 것으로 인장강도 200KSI 이상이 요구되는 항공기용 또는 로켓트 추진기관용 초고강도강에서 크게 문제가 되고 있다. 본 내용은 전기 카드뮴도금 작업시에 발생되는 수소취성에 대하여 간략하게 기술하고. 이 수소취성을 제거하는 방법 및 수소취성을 저게 생성시키는 저취성도금인 Cd-Ti 합금도금의 공정개발 결과를 보고한다. 실험결과에 의하면 도금층의 Ti함량은 0.1-0.7%이며 Ti의 공석에 의하여 Cd 도금에 비하여 저취성을 나타냈으며, Cd-Ti합도금의 내식성은 상대평가인 염수분무시험 결과 Cd도금과 비교하여 소재표면의 부식을 일으키는 붉은녹발생까지의 시간이 500시간으로 보다 높은 내식성을 나타내었다. 그리고 Cd-Ti 합금의 공정표준 및 Ti농도의 관리방법 등을 정리하여 보고한다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1994.04a
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• pp.3-9
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• 1994

초고강도 마레이징강의 초박판 고정밀 연소관의 유동성형공정 조건을 도출하기 위하여 치수제어 시험을 실시하고 가공열처리 공정이 적용된 연소관의 물성 및 구조시험을 통해 신뢰성을 평가하였다. 두께 0.5mm 이하인 초박판 연소관의 유동성형에서 두께증가 현상은 성형속도 0.5-0.75mm/rev에서 X롤러의 성형비를 상대적으로 10%이하로 하고. 성형반경을 4mm로 작게 함으로써 제어할 수 있었으며. 이와 같이 개발된 연소관은 인장강도가 300ksi 이상으로 크게 강화되었고, 예상 최대작동압력에 대한 안전계수가 1.3 이상으로서 구조적 안전성이 입증되었다.

• Journal of Acupuncture Research
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• v.24 no.5
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• pp.127-136
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• 2007

Objectives : To review the history, the theoretical basis and the technique of Intramuscular Stimulation (IMS), papers and books on IMS were searched. Methods : 15 papers were searched with the keyword 'Gunn CC' at Pubmed(http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed). Several full texts of them and other papers were found at the internet homepage of The Institute for the Study and Treatment of Pain (http://www.istop.org/). 16 Korean papers on IMS were searched at KoreaMed(http://www.koreamed.org/SearchBasic.php) and Koreanstudies Infomation Service System(http://kiss.kstudy.com/KsiKiss.asp). Results : Dr. Gunn has made unique model which can explain the pathology of chronic pain and the mechanism of acupuncture treatment. In this model, he postulated that most of chronic pain is radiculopathy due to spondylosis and acupuncture treatment to the hyperalgesic muscle can restore the normal function of involved muscles and nerves. Conclusions : IMS is an acupuncture technique in which the muscles under the Ah-shi or tender points in periphery and intrasegmental paravertebral muscles are stimulated with needles.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.3
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• pp.548-553
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• 2009

In this study, after we analyzed 44 recent research paper written about obesity treatement, we tried to understand the acupuncture on the obesity treatment of the recent trend. We searched the recent papers with the key word of obesity, obese, and Acupuncture and are limited since 2004 in the search site KISS, KSI. Recently, acupuncture application for obesity treatment were 6 type. Traditional Acupuncture, Auricular Acupuncture, Electro Acupuncture, Herbal Acupuncture, Chi Acupuncture, and Acupoint Catgut Embedding Therapy. Although acupuncture application were effective method to decrease weight and localized fat, they were critical to evaluate to their effectiveness through strict and scientific clinical trials.

• Korean Journal of Materials Research
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• v.13 no.4
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• pp.224-227
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• 2003

The sliding wear behavior of a Fe-base hardfacing alloy was investigated in the temperature range of $25∼250^{\circ}C$ under a contact stress of 15 ksi (103 MPa). The wear loss of this Alloy in pressurized water was less than that of NOREM 02. And galling did not occurred at this alloy in all temperature ranges. It was considered that the wear resistance of this Alloy was attributed to the strain-induced phase transformation from austenite to $\alpha$'martensite during sliding wear.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.26-26
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• 2003

The backbone dynamics of ketosteroid isomerase, a homodimeric enzyme with 125 amino acid residues per subunit, has been studied in the presence/absence of a steroid ligand and 5％ trifluoroethanol (TFE) by $^{15}$ M relaxation measurements. The relaxation data were analyzed using the model-free formalism to extract the model-free parameters (S$^2$, $\tau$$_{e}$, and R$_{ex}$ ). The results show that a large number of the residues, particularly those involved in the dimer interaction, exhibit reduced order parameters (S$^2$) in the steroid-bound enzyme, indicating the increased high-frequency (pico- to nanosecond) motions in the interface region upon ligand binding. The results also show that that the presence of 5 ％ TFE in free enzyme causes little change or slight increase in the order parameters for a number of residues in the dimer interface region. However, the majority of the residues in free enzyme exhibit reduced order parameters in the presence of 5 ％ TFE, indicating that the increase in entropy is partially responsible for the increased stability of KSI by 5％ TFE.E.E.

• International Journal of Concrete Structures and Materials
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• v.7 no.4
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• pp.253-264
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• 2013

A major difference between high-strength reinforcing steel and conventional steel in concrete is that the service-load steel stress is expected to be greater. Consequently, the service-load steel strains are greater affecting cracking behavior. A parametric study investigating crack widths and patterns in reinforced concrete prisms is presented in order to establish limits to the service-load steel stress and strain. Additionally, based on the results of available flexural tests, crack widths at service load levels were evaluated and found to be within presently accepted limits for highway bridge structures, and were predictable using current AASHTO provisions. A limitation on service-level stresses of $f_s{\leq}414$ MPa (60 ksi) is nonetheless recommended.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.33-33
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• 2001

Bacterial Δ$\^$5/-3-ketosteroid isomerase (KSI) is one of the most proficient enzymes catalyzing the isomerization of a variety of Δ$\^$5/-ketosteroids to Δ$^4$-ketosteroids at a diffusion-controlled rate. Because of the simplicity of the reaction, the enzyme mechanism has been intensively studied as a prototype to understand enzyme-catalyzed C-H bond cleavage.(omitted)

• Journal of Korean Society on Water Environment
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• v.27 no.2
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• pp.218-227
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• 2011

The objective approach for assessment of stream naturalness is an essential part of the stream restoration project. This study proposes the methodology for the assessment of stream naturalness considering physical, biological and chemical factors. Physical factors consists of riffle and pool, river bed material, bank protection, floodplain vegetation and levee materials; biological factors are benthic macroinvertebrate, KSI (Korean Saprobic Index), and IBI (Index of Biological Integrity) and chemical factors are pH, DO (dissolved oxygen), and TP (total phosphorus). This procedure is applied to the Mokgamcheon. As a result, the downstream of Mokgamcheon (zone I) needs the prompt improvement of stream naturalness, compared to the others (zone II and III). This evaluation technique will be an effective tool to quantify the stream naturalness and can be used to set the target of stream restoration project.