• 한국전자파학회논문지
• /
• 제11권8호
• /
• pp.1363-1375
• /
• 2000

접지된 유전체 슬랩 위에 주기적으로 스트립이 놓여 있는 격자구조에 대한 전자파 산란 특성을 TM편파의 경우에 대하여 반사격자(reflection grating)관점과 누설파안테나(leaky wave antenna)관점에서 조사하였다. 수치해석 결과로 Bragg blazing 현상을 두가지 형태(공진형과 비공진형)로 구분하였으며 그 특성(복소전파상수, 산란특성, 전류밀도분포)에 대하여 논의하였다. 특히, 본 연구구조의 TE 및 TM편파 경우에서 확인한 Bragg blazing 현상에 관하여 상세히 기술하였다.

• 한국산학기술학회논문지
• /
• 제19권8호
• /
• pp.183-192
• /
• 2018

본 연구는 간호대학 여학생의 음주실태, 음주동기와 문제음주의 상태 비교를 하고자 실시하였다. 연구대상자는 일부 지역 간호 대학생을 대상으로 하였고, 자료수집기간은 2018년 4월부터 5월까지이며, 분석대상은 181명 이었다. 자료 분석은 정상음주 군과 문제 음주 군과의 차이를 알아보기 위하여 빈도 분석을 사용하였고, 문제음주와의 상관관계는 Pearson's correlation을 이용하였으며, 문제음주 관련요인을 분석하기 위해 로지스틱회귀분석(Logistic regression)을 실시하였다. 그 결과 음주횟수, 마시는 속도, 음주동기, 생활스트레스, 음주문제발생경험이 문제음주에 대한 위험비가 높았다. 구체적으로 살펴보면, 음주횟수로 볼 때 음주횟수가 일 년에 1-4회인 군보다 일주일에 2-3회인 군에서 문제음주에 대한 위험비가 21.53배 높았으며, 음주동기는 음주동기가 낮은 군 보다 음주동기가 높은 군에서 5.96배, 음주문제발생경험은 음주문제발생경험이 낮은 군에 비해 음주문제발생경험이 높은 군에서 8.80배 문제음주에 대한 위험비가 높게 나타났다. 결론적으로, 여대생의 문제음주 관련 요인은 음주횟수, 마시는 속도, 음주동기, 생활스트레스, 음주문제발생경험이 관련성이 높게 나타났다. 따라서 대학생들의 음주실태와 위험요인을 파악하고, 주기적인 절주교육, 문제음주선별과 예방프로그램을 통해 문제음주가 될 위험성을 낮추고, 건전음주문화 정착을 위해 노력해야 할 것이다.

• Clinical and Experimental Pediatrics
• /
• 제51권9호
• /
• pp.922-934
• /
• 2008

Developmental language disorder is the most common developmental disability in childhood, occurring in 5-8% of preschool children. Children learn language in early childhood, and later they use language to learn. Children with language disorders are at increased risk for difficulties with reading and written language when they enter school. These problems often persist through adolescence or adulthood. Early intervention may prevent the more serious consequences of later academic problems, including learning disabilities. A child's performance in specific speech and language areas, such as phonological ability, vocabulary comprehension, and grammatical usage, is measured objectively using the most recently standardized, norm-referenced tests for a particular age group. Observation and qualitative analysis of a child's performance supplement objective test results are essential for making a diagnosis and devising a treatment plan. Emphasis on the team approach system in the evaluation of children with speech and language impairments has been increasing. Evidence-based therapeutic interventions with short-term, long-term, and functional outcome goals should be applied, because there are many examples of controversial practices that have not been validated in large, controlled trials. Following treatment intervention, periodic follow-up monitoring by a doctor is also important. In addition, a systematized national health policy for children with speech and language disorders should be provided.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2007년도 춘계 학술대회논문집
• /
• pp.120-124
• /
• 2007

Helicopters and rotary-wing vehicles encounter a wide variety of complex aerodynamic phenomena and these phenomena present substantial challenges for computational fluid dynamics(CFD) models. This investigation presents the rotor aerodynamic analysis items for the helicopter development and variety aerodynamic analysis methods to provide the better solution to researchers and helicopter developers between aerodynamic problems and numerical aerodynamic analysis methods. The numerical methods to make an analysis of helicopter rotor are as below - CFD Modelling : actuator disk model, BET model, fully rotor model,... - Grid : sliding mesh, chimera mesh / structure mesh, unstructure mesh,... - etc. : panel method periodic boundary, quasi-steady simulation, incompressible,... The choice of CFD methodology and the numerical resolution for the overall problem have been driven mostly by available computer speed and memory at any point in time. The combination of the knowledge of aerodynamic analysis items, available computing power and choice of CFD methods now allows the solution of a number of important rotorcraft aerodynamics design problems.

• 한국산학기술학회논문지
• /
• 제3권1호
• /
• pp.10-19
• /
• 2002

본고는 다종, 소규모 회분식 공정 또는 공장을 수학적 프로그래밍 기법으로 최적 설계하는 방법에 대한 것이다. 제안된 일반 회분식 공장문제는 Papageorgaki와 Reklaitis에 의해 혼합정수비선형식(MINLP)으로 수립된 것인데, 최적해답을 보장하며 공장의 확장 등 불확실성을 고려하여 선형화 한 후(MILP) 푸는 방법론이 제시되었다. Bende식 문제분할 방식을 개조하여 몇가지 예제에 대한 풀이를 제시하였다. IBM의 OSL 최적화 패키지를 이용하였고 MILP를 직접 푸는 경우보다 계산시간을 크게 단축할 수 있었다.

• International Journal of Advanced Culture Technology
• /
• 제7권3호
• /
• pp.46-51
• /
• 2019

This study suggests ways to strengthen the expertise by analyzing the problems caused by the lack of expertise of the qualification management body managing the Korean qualifications in the realm of firefighting from the perspective of external signal dependency of capture theory. As a method to prevent the dependency of external signals in capture theory, it is suggested to strengthen the expertise of regulators and strengthening roles and functions of regulator institutions by supplementing education and professional manpower. On this basis, analyzing the problems of qualifications management to the external signal dependency tendency, the researchers in qualification management at the Human Resources Development Service of Korea have a variety of different majors, so understanding and application can be limited if they are working in an unfamiliar area of work. Therefore, in making decisions regarding topics such as policies and roles, suitable alternatives should be found based on external signals. In order to improve this, it is necessary to select firefighting majors in the Korean qualification management of the firefighting realm, to reorganize the job scope to a similar job field of the researcher in charge. It is also necessary to strengthen the expertise of the researcher through various programs, such as mandatory periodic maintenance education in order to understand the work of the researcher.

• 한국산업보건학회지
• /
• 제30권1호
• /
• pp.28-38
• /
• 2020

Objectives: The purpose of this study is to identify the perceived problems of and suggest improvement measures for asbestos abatement companies in support of asbestos-related systems and policies. Methods: For this study a questionnaire was prepared consisting of current work (two questions), the contribution and necessity of a risk assessment system for asbestos abatement (two questions), and problems with and improvement measures for systems and policies (nine questions). The questionnaires were sent to 2,170 asbestos abatement companies and were returned by 83 companies (return rate = 3.8%). We conducted frequency analysis, ANOVA, and a Chi-squared test at the 5% significance level. Results: Asbestos abatement companies expressed difficulties with complying with wet work (43% of unenrolled managers), negative pressure enclosure (36% of all respondents), and installation and use of decontamination units (26% of all respondents) as stipulated in the relevant regulations. In addition, 43% of the respondents expressed concerns that the expertise of the company was not considered during bidding for asbestos abatement and hoped that an advantage (e.g., bid point) would be given to the upper grades for asbestos risk assessment (38%). Asbestos abatement companies generally rented and used negative pressure devices (including negative pressure recording devices) and suggested that periodic calibration (32%) is needed to ensure the performance of the rented equipment. Finally, the respondents asked for clear definitions for three situations specified in the Occupational Safety and Health Acts: (1) temporarily leaving the asbestos abatement workplace; (2) tasks with less airborne asbestos; and (3) physically breaking or cutting using a machine. Conclusions: The problems and improvement measures identified in this study of asbestos abatement companies can be utilized as fundamental information for the improvement of the systems and policies for safe asbestos abatement.

• 한국의상디자인학회지
• /
• 제17권2호
• /
• pp.27-43
• /
• 2015

Festival costume shown in festival parades targeting historical events or figures helps to understand the theme of festival and grants visual effects and at the same time, is an important factor to identify then-cultural environment. Accordingly, this study aims to make a periodic review of traditional costumes used in parades for Hanseong Baekje Cultural Festival and Yeongam Wangin Cultural Festival which are both the festivals that backgrounded Baekje period, make a comparative analysis of the archetypes of reproduction costume vs Baekje costume, understand the problems of festival costume, and seek developmental directions. After making a comparative analysis of reproduction costume shown in festival parades, it was found that king costume, queen costume, governmental official costume, and humble class costume were all different from Baekje costume in terms of configuration, materials, color, shape, and creating method of costumes, and problems were drawn. When it comes to costume items, Pasul and Danryungpoh that didn't belong to Baekje period were worn. The problems in color research can be identified in governmental official costume. The problems in type of costume are shown in the length of po worn outside, margin of width, and degree of restoring accessories. Therefore, it seems to be necessary to convey and identify costume creating method by festival parade-related persons.

• 한국학교보건학회지
• /
• 제1권1호
• /
• pp.160-177
• /
• 1988

This study is an analysis of the teachers' health problems that focuses on the frequencies and types of their visiting to school clinics and the management of health-related problems. The participants for this study are consisted of 1,650 teachers employed at 30 public schools in the Seoul area. Data for the study came from diagnostic records for 1986, the results of a questionaire-type survey conducted between June 20th and of the same year an from other documents recorded by school nurses. The main results of this study are as follows: 1. The teachers' health problems. a) According to health diagnosis records, 6.1 % of all teachers had a health problem. Liver-related ailments topped the list, followed by circulatory and diabetic problems. b) The survey data had 71.9 % of the respondents indicating that trey suffered from some health problem. The most frequent response concerned respiratory problems, followed by gastro-intestinal and nervous system problems. c) A check of clinic utilization records revealed that the main reasons for visiting are concerned with fatigue (30.5 %), gastro-intestinal(18.7 %) and respiratory(18.2 %) ailments. These three categories accounted for 67.4 % of total use. 2. Frequencies of their visiting to school clinics 40.5 % of the teachers indicated that they have visited the school clinic. And 62.0 % visited it with a self-diagnosed ailment and 15.3 % utilized the facility after a problem had been detected in a health examination. Clinics were visited a total of 1,458 times which breaks down to 0.9 times per month per teacher. For a patient, the figures are 2.2 times on the average with a range from 1 to 19. 3. Health management problems a) Of those respondents. 53.4 % stated that they didn't have enough time to consult about their health problems and diagnose their disease b) Also, 47.3 % of the respondents indicated that school nurses should give health counsels and health education. c) When questioned about improvements in the current system, the teachers placed importance on the prevention and management of chronic diseases (35.2 %) and pre- and posteducation concerning periodic health examinations In conclusion, the following points must be considered: First, school administrators need to pay more attention to the health problems of the teachers. Second, school nurses should be more active in managing a health program for teachers. Finally, education and training for nurses should be continually upgraded so that they can dispense proper and timely care for teachers.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회B
• /
• pp.3236-3240
• /
• 2007

This paper describes the results of steam turbine performance tests. The objectives of performance test is to exactly evaluate the degradation(decrease in performance) of the coal-fired steam turbine generator in order to provide plant information to help performance engineers identify problems, improve performance, and make economic decisions about scheduling maintenance and optimizing operation. To achieve these goals, the periodic thermal performance tests have been carried out since the initial operation period, 1997. We made the calculation program and guidelines for the tests and developed the performance index of the turbine cycle on the basis of the ASME PTC. By comparing the performance changes throughout the whole operation period, we confirmed the performance reliabilities of the turbine and its conditions.