• Journal of Advanced Marine Engineering and Technology
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• v.39 no.7
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• pp.779-785
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• 2015

Cathodic protection is recognized as the most cost-effective and technically appropriate corrosion prevention method for the submerged zone of offshore structures, ships, and deep-sea facilities. When cathodic protection is applied, the cathodic currents cause dissolved oxygen reduction, generating hydroxyl ions near the polarized surface that increase the interfacial pH and result in enhanced carbonate ion concentration and precipitation of an inorganic layer whose principal component is calcium carbonate. Depending on the potential, magnesium hydroxide can also precipitate. This mixed deposit is generally called "calcareous deposit." This layer functions as a barrier against the corrosive environment, leading to a decrease in current demand. Hence, the importance of calcareous deposits for the effective, efficient operation of marine cathodic protection systems is recognized by engineers and scientists concerned with cathodic protection in submerged marine environments. Calcareous deposit formation on a marine structure depends on the potential, current, pH, temperature, pressure, sea-water chemistry, flow, and time; deposit quality is significantly influenced by these factors. This study determines how calcareous deposits form in sea water, and assesses the interrelationship of formation conditions (such as the sea water temperature and surface condition of steel), deposited structure, and properties and the effectiveness of the cathodic protection.

• The korean journal of orthodontics
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• v.36 no.3 s.116
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• pp.207-217
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• 2006

Although ceramic brackets have been used widely for improved esthetics during treatment, ceramic brackets have some inherent problems; brittleness, attrition of the opposing teeth and high frictional resistance. This study was performed to understand the frictional resistance of the ceramic brackets, as well as to be a helpful reference for finding the solutions to the problem of frictional resistance. Three different kinds of brackets were used; metal bracket, polycrystalline ceramic brackets with a metal slot to reduce the high frictional resistance and monocrystalline ceramic brackets. The brackets were tested with a $.019{\times}.025$ stainless steel wire with a second order angulation of $0^{\circ}\;and\;10^{\circ}$, and the static and kinetic frictional forces were measured on the universal testing machine. The results of this study showed that the ceramic brackets, especially the monocrystalline ceramic bracket without a metal slot, generated higher frictional resistance than the metal bracket, and the frictional resistance was increased as the angulation between the bracket slot and the wire increased. Therefore, the development of the ceramic bracket with reduced frictional resistance and the prevention of excessive crown tipping during orthodontic treatment will lead to the simultaneous attainment of more efficient and improved esthetic treatment goals.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.2
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• pp.27-37
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• 2013

The purpose of this research is to identify the selection status of the evaluation index in Korea and suggest improvements. In order to do so, comparison and analysis are conducted of terms, items and measures for biotope evaluation indexes attested in related documents published in domestic and foreign areas. The findings of this research are listed in the following. First, terms about biotope evaluation indexes are used and integrated with each other. Second, items used to denote biotope evaluation indexes are largely different in each region since comprehensive concepts have not been established for selecting the items. Third, there are poor grounds for items denoting biotope evaluation indexes to the species of creatures. Fourth, the items cannot provide satisfying explanations for the relative values of the current condition in the urban ecosystem of a specific region. The results of this research may be applied to provide basic materials about what is to be improved for selecting biotope evaluation indexes in Korea. In order to systematically preserve an urban ecosystem environment in Korea for the future, it is necessary for the state to develop and set up such evaluation indexes and guidelines that reflect the relative values of biotopes in each level of urban areas in Korea.

• Journal of Pharmacopuncture
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• v.6 no.1
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• pp.33-34
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• 2003

배경: 독일 의사와 보험회사 위원회 (The German Board of Physicians and Insurance Companies:Bundesausschuss der Arzte und Krankenkassen)가 앞으로 일부 적응증에 대한 침치료에 대해 공적 보험회사가 보험료를 지급해야 할 지에 대한 추가 결정을 하기 위해 침의 효과를 평가하기로 했다. 목적: 1) 침치료가 편두통의 예방, 긴장성 두통, 요통, 무릎과 고관절의 골관절염치료에 대조군 침치료보다 효과가 있는지 검증 2) 침치료가 편두통의 예방적 치료에 표준 약물 치료와 비슷하게 효과가 있는지 검증 3) 보건의료 서비스체계 안에서 주어진 조건에 대한 일상적 침치료의 질적인 부분을 서술하고, 안전성을 평가하며, 다른 침술학파간의 임상결과의 차이와 비용의 효용적 활용부분을 평가한다. 4) 위의 적응증에 해당하는 모든 임상실험연구를 찾아내어 기존의 고찰내용을 갱신한다. 방법: 1) 무작위 표본추출 임상 실험, 침치료, 거짓침 치료, 대기자 명단 대조군, 출발시점 4주, 28주 관찰 2) 무작위 표본추출 임상 실험, 침치료, 표준약물치료 대조군, 츨발시점 4주, 28주 관찰 3) 전향적 다중 의료기관 관찰 연구, 두 가지 다른 자료를 활용하여서, 치료 결과를 침 시술자에 의한 모든 환자 평가 자료와, 열 두 명의 환자 가운데 한 명의 환자로부터 직접 받은 평가 자료 (관찰 출발시점, 치료 출발 시점, 치료 시작 후 6 개월) 실험공간: 1) and 2) 높은 수준의 수련을 한 침 시술 의사가 시술하는 병원이나 일차 진료기관의 외래. 3) 보건 의료 서비스내 저급의 침 시술 의사 (140 시간 수강, 학점 이수 필수) 참가자: 1) $4{\times}320$ 편두통의 예방, 긴장성 두통, 요통, 무릎과 고관절의 골관절염 환자 2) 480 편두통 환자(긴장성 두통 환자 추가적) 3) 약 500,000 환자, 2년 반 동안: 대략 한 적응증 당 10,000 환자 치료법: 모든 침치료 자리는 체침만 허용함. 1) 진짜 침은 학파의 지침에 따른 심자, 거짓 침은 비특이적 자리의 표피만 찌르는 자침 (12-15회, 8주): 대기자 대조군은 12주 동안에 아무 치료도 받지 않는다. 2) Group 1(N=240): 최대 15회 치료, 12주 동안: Group II (N=240) 투약 Proponolol (80-240mg), Metoprolol (100-200mg) or Flunarizin (5-10mg) 하루, 16주 이상 3) 치료회수와 침자리의 선정은 참가자가 결정 주된 임상 결과 지표: 1) 군 간의 치료 전 및 치료 진행 도중 4주 마다의 두통을 느낀 날 수의 차이 (평균 혹은 이상의 편두통이나 긴장성 두통) 2) 요통환자 군간의 기능을 측정하는 FFbH-R (Funktionsfragebogen Hannover) 비교 3) 관절염 환자의 군간 WOMAC 지표 비교 4) 군 간의 24주 동안 두통을 느낀 날 수의 차이(평균 혹은 이상의 편두통이나 긴장성 두통) 5) 적응증, 부작용, 성공율에 대한 거시적 평가, 사용한 침수, 환자의 만족도, SES(?). ADS(?) 통증 장애 지표(PDI), 삶의 질 지표(SF36). 예비 결과 위의 결과가 큰 관찰 연구에 초점을 맞추면서 소개될 것임.

• Journal of the Society of Disaster Information
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• v.9 no.4
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• pp.503-510
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• 2013

Recently, localized heavy rain is increased by climatic changes and landslide is increased. Also, because of landslide occurred in urban area, life and property damages are increased. Therefore, standard operation procedure of disasters should be established by steps and institutions so as to respond landslide. This thesis investigated application of current disaster manual so as to write SOP of landslide for disaster prevention related experts and accepted opinion for responding necessaries by using landslide SOP and important matters by step of disaster management. As the result of investigation, application of manual was low during the current response to disasters and application was the highest in responding step among the steps of disaster management. In case of landslide, they responded that response with SOP is necessary. During the organization of landslide SOP, they responded that training and education for landslide disaster are important at the step of prevention, conduction of landslide disaster broadcasting and provision of information are important at the step of preparation, guidance for evasion and behavior methods is important at the step of response and investigation of landslide disaster damages and reflection of record and evaluation are important at the step of recovery. In addition, for the requests for landslide SOP application, there was an importance of secondary factors such as expansion of professional manpower, strengthening of law and institution, education and training for SOP acquisition, etc.

• Radiation Oncology Journal
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• v.8 no.1
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• pp.65-71
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• 1990

Between January,1974 and December 1980, fifty eight patients with locoregional recurrent breast carcinoma who did not have evidence of distant metastasis after initial treatment of surgery with or without adjuvant chemotherapy were treated with radiation therapy. Among them, five patients were excluded from this study because of incomplete record or incomplete treatment. The 5-year overall survival and disease free survival from the time of locoregional recurrence was $27\%\;and\;15\%$ respectively. In univariate analysis of prognostic variables, the clinical stage at initial diagnosis, recur duration, number of recurrence sites, size of recurrences, response to the treatment, remission duration were all found to have no significant effect on survival or disease free survival. On the other hand, menopausal status at initial diagnosis, number of positive node at initial surgery, whether or not the use of adjuvant chemotherapy after initial mastectomy had definite prognositc significance. In multivariate analysis of prognostic variables, remission duration, menopausal status at diagnosis, number of axillary node at mastectomy had definite prognostic significance. On the other hand, remission duration more than 12 months, premenopaus at initial mastectomy, less than four positive axillary lymph nodes at mastectomy predicted a good prognosis.

• Korean Journal of Organic Agriculture
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• v.21 no.2
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• pp.233-246
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• 2013

This study was performed to investigate the recognition of Korean farmers for the safety of environment-friendly organic materials (EFOMs). The main purchase line of environment-friendly organic materials was the sustainable agriculture organizations, and decisive basis for the materials purchase was because they thought that agricultural produce cultivated with EFOMs were safe. Currently farmers obtained the most information about EFOMs through farmer's education operated by agricultural technology center. Sixty nine percent of respondents hoped that they would get the information on the website and through official education opened by of the government or relative institutions. Whereas, only a few respondents hoped that they would get the information from the sellers. Therefore we thought that government and related institutions should operate the education program to give the sellers the scientific and accurate information about EFOMs. In addition, farmers are highly recognized the necessity of safety-related information provided by government and related institutions. Most Farmers thought that safety education for farmers using EFOMs was very important. Also, it was confirmed that farmer respondents thought to need to establish the shelf-life and user guideline and to label about toxic category of EFOMs. The Cronbach' alpha coefficient calculated in order to verify the reliability of survey questions was 0.699. That value indicates that responses of the respondents in this study might be reliable.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.5
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• pp.871-878
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• 2017

The quality control personnel of the construction work shall establish and execute the quality control plan or the quality test plan and check the qualification of the used materials according to the process, the management of the test and inspection equipment, the quality education, the own quality inspection and measures. Management and quality test of Korea and plays an important role in preventing accidents. However, related organizations did not explicitly disclose their roles in quality testing and quality control tasks while changing the names of quality control personnel to test personnel and quality managers when revising related laws and regulations and the application of labor costs. Therefore, a research of this is needed to improve conflicting situation. In this study, the ambiguous title relation to the quality control persons is improved to meet the requirements of the construction work based on related laws and regulations, and each role and title is classified as 'quality tester' and 'quality manager'. In other words, the person who carries out the quality test of the "Construction Quality Test Standard" specified in the Guideline for Quality Management of Construction Projects shall be the "Quality Tester" and the person who performs the quality control plan establishment and execution work specified in the Enforcement Rule of the Construction Technology Promotion Act shall be referred to as the 'Quality Manager'.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3418-3426
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• 2009

The purpose of this study was to investigate the feasibility of field operation protocol for cardiopulmonary resuscitation(CPR) in person with non-traumatic arrest. This study was performed from May 1 through June 27, 2008, and subjects were 150 students who are attending the department of Emergency Medical Service in J and K universities which located in Jeollabuk-do and Jeollanam-do areas. Practical conformance was verified using by nonequivalent control group pretest-posttest design. This study divided into two groups; experimental group that employed field operation protocol and control group that applied conventional CPR protocol, and comparative analyzed statistically the necessary time of the items of each protocol. The results indicated that each performance time of 18 items was reduced over 3 seconds except 5 items(assessment of consciousness, airway control, two times of artificial respiration, check of circulation, and five cycles of CPR). And time of 6 items(intubation, peripheral intravenous line, reassessment of consciousness, pupil reaction, carotid artery pulse, and vital sign) was minimized more than 60 seconds, and total performing time was shortened 110.85 seconds. The results suggested that total performing time in pre and post test where the protocol was applied for two groups showed a statistically significant decrease(t=-6.580, p=.000). Consequently, field operation protocol for cardiopulmonary resuscitation(CPR) in person with non-traumatic arrest will be a available manual which support prompt and accurate decision making, and improve emergency medical service.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.2
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• pp.23-30
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• 2009

Crash cushions are protective devices that prevent errant vehicles from impacting on fixed objects. This function is accomplished by gradually decelerating a vehicle to a safe stop in a relatively short distance. Commonly used crash cushions generally employ one of two concepts to accomplish this function. The first concept involves the absorption of the kinetic energy of a moving vehicle by crushable or plastically deformable materials and the other one involves the transfer of the momentum of a moving vehicle to an expendable mass of material located in the vehicle's path. Crash cushions using the first concept are generally referred to as compression crash cushions and crash cushions using the other concept are generally referred to as inertial crash cushion. The objective of this research is the development of a compression-type crash cushion by employing the two concepts simultaneously. To minimize the number of full-scale crash tests for the development of the crash cushion, preliminary design guide considering inertial and frictional energy absorption was constructed and computer simulation was performed. LS-DYNA program, which is most widely used to analyze roadside safety features, was used for the computer simulation. The developed crash cushion satisfied the safety evaluation criteria for various impact conditions of CC2 performance level in the Korean design guide.