• 소성∙가공
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• 제32권6호
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• pp.335-343
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• 2023

Spur Gear parts for automobile actuators using existing former forging technology were produced in a total of three processes on a former forging machine. However, in order to improve cost increase due to frequent mold breakage, Spur Gear parts were designed and manufactured in the cold forging process after forming the preform through former forging. In other words, in the existing former forging mold, product seating defects occurred due to horizontal movement, resulting in many product defects and mold damage, so there was an urgent need to improve mold life and product defects. In order to improve this, we tried to improve the mold life by improving the existing 3 former forging processes to a former forging process and 2 cold forging processes. Therefore, We developed Spur Gear parts for automobile actuators were developed by applying precision cold forging technology through a former forging process and 2 cold forging processes to improve mold life.

• 대순사상논총
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• 제48집
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• pp.199-237
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• 2024

동학교는 김주희가 세운 동학계 신종교단이다. 동학교가사에 나타난 사상의 요체는 용어의 빈도수와 읊어진 구절의 내용을 고려하여 '도로 선천(先天)'사상이라고 볼 수 있다. 동학의 시운관(時運觀)이 '다시 개벽(開闢)'사상이라면, 동학교의 시운관은 '도로 선천(先天)'사상이다. 동학교에서는 선천이라는 용어를 특히 강조했고, 역학(易學)을 활용하여 노래했으며, '음양의 마주 봄'으로 개벽의 상황을 읊었다. 동학교에서는 후천의 운수마저 다한 다음에야 비로소 '도로 선천'이 이루어지리라고 강조한다. 이 '도로 선천'의 운수가 회복되면 목덕(木德)으로 상징되는 '봄<춘(春)>'이 다시 돌아올 것이라고 노래한다. 동학교에서는 새로운 운수(運數)의 전개를 '역(易)의 회복'으로 설명한다. 새로운 질서와 규범이 전개될 새 세상을 '도로 선천'으로 부르는데, 이때가 되면 '도덕세계'가 이루어져 도덕 문명이 전개될 것이라고 주장한다. '도로 선천'을 회복하는 운수가 바로 천도(天道)가 회복되는 일과 같다고도 노래한다. '도로 선천'사상의 특성은 첫째, 복고적 체계를 지향한다. 둘째, 과거지향적 사상이다. 셋째, '도로'는 '근원으로 돌아가자.', '근본을 회복하자.'라는 실제의 행동을 유발하고 권유하는 생각이다. 동학교의 '도로 선천'사상은 당대의 여러 신종교와는 다르게 선천(先天)에 대해 독창적인 관념과 인식을 부여했으며, 새로운 해석의 틀을 제시했다. 선천을 폐기해야만 할 낡은 시대로 규정했던 일에서 벗어나 지향해야 할 새 시대로 이해했다. 따라서 동학교의 '도로 선천'사상은 동양 전통의 과거로의 회귀와 복귀를 추구하던 일을 계승한 사상의 하나로 재평가되어야 하겠다. 하지만 '도로 선천'사상에 구체적 방법론이 매우 부족하다는 점은 단점으로 지적될 수 있다. 그리고 동학교의 '도로 선천'사상에는 윤리의식이나 도덕적 덕목이 부족하며, 정작 선천(先天)에 대한 설명이 부족하다. 따라서 동학교의 '도로 선천'사상은 선언적 구호에 그친 감이 있다.

• Ecology and Resilient Infrastructure
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• 제4권2호
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• pp.97-104
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• 2017

우리나라의 하천은 대부분 치수를 위한 제방공사를 통해 직강화되어 있다. 하천과 홍수터의 횡적 연결성을 회복하기 위해서는 제방에 의해 격리된 옛홍수터를 탐색하고 현재 토지이용현황을 파악하는 것이 중요하다. 본 연구의 목적은 청미천에서 옛홍수터를 탐색하고 토지이용현황을 분석하는 것이다. 옛홍수터는 지리정보시스템을 이용하여 청미천 유역에서 수치표고모델, 연속수치지도 및 계획홍수위를 중첩하여 산출하였다. 탐색된 옛홍수터의 토지이용현황은 토지피복도를 이용하여 분류하였다. 청미천에서 격리된 옛홍수터는 총 104 지점이 탐색되었으며, 전체면적은 11.9 km2이었다. 옛홍수터의 토지이용은 농경지가 87.1%로 대부분을 차지하였다. 청미천의 하류에는 산지로 둘러싸인 소규모 패치 형태의 옛홍수터가 많았으며, 이러한 지역은 시가화지역의 비율이 낮고, 농경지의 비율이 높아 하천 횡적 연결성 복원의 효율이 높을 것이다. 청미천에서 탐색된 격리된 옛홍수터와 토지이용 현황은 향후 하천 복원계획에 기초자료로 이용될 수 있을 것이다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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• pp.6563-6568
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• 2013

Background: Tobacco use and quit attempts are two key indicators of the Global Adult Tobacco Survey (GATS) that assess quit attempts among current as well as former tobacco users. The relevant data have inherent policy implications for tobacco cessation programme evaluation. This study aimed to review the concepts of quit attempt assessment and quantifying invalid responses considering GATS-India data. Materials and Methods: GATS assessment of tobacco use and quit attempts were examined in the current literature. Two categories of invalid responses were identified by stratified analysis of the duration of last quit attempt among current users and duration of abstinence among former users. Category A included absolute invalid responses when time-frame of assessment of current tobacco use and less than former tobacco use were violated. Category B included responses that violated the unit of measurement of time. Results: Current daily use, current less than daily use and former use in GATS were imprecisely defined with overlapping of time-frame of assessment. Overall responses of 3,102 current smokers, 4,036 current smokeless users, 1,904 former smokers and 1,343 former smokeless users were analyzed to quantify invalid responses. Analysis indicated overall 21.2% (category A: 7.32%; category B: 17.7%) and 22.7% (category A: 8.05%; category B: 18.1%) invalid responses among current smokers and smokeless users respectively regarding their duration of last quit attempt. Similarly overall 6.62% (category A: 4.7%; category B: 2.3%) and 10.6% (category A: 8.6%; category B: 3.5%) invalid responses were identified among former smokers and smokeless users respectively regarding their duration of abstinence. Conclusions: High invalid responses for a single assessment are due to the imprecise definition of current use, former use and quit attempt; and failure to utilize opportunity of direct data entry interface use during the survey to validate responses instantly. Redefining tobacco use and quit attempts considering an appropriate timeframe would reduce invalid responses.

• 가족자원경영과 정책
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• 제17권2호
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• pp.147-172
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• 2013

The purpose of this study was to examine the relative influences of variables that affect baby boomers' perceptions and preparations for later life planning. An age-group comparison was made to examine differences in later life planning within baby boomers. 814 respondents were selected from The National Survey of Korean Families undertaken by the Ministry of Equality and Family in 2010. They were devided into two groups according to the year of their birth, the former baby boomers was 397 respondents who was born from 1955 to 1959, and the latter baby boomers was 417 respondents who was born from 1960 to 1963. The major results of this study were as follows: First, the former baby boomers was less likely to prepare for later life, while was more likely to be aware of their later life planning than the latter baby boomers. Second, educational attainment and the number of children affected the level of perceptions and preparations for later life planning of the former baby boomers, whereas sex and region affected those of the latter baby boomers. Third, household income and subjective awareness of economic status were the major determinants of the preparation level for later life by both the former and the latter baby boomers. Fourth, former baby boomers who had greater awareness of the need to support their parents and their children were more likely to prepare for later life. Fifth, baby boomers' subjective awareness of their economic status chiefly explained the gap between their level of perceptions and their preparation for later life, with the former baby boomers with more children and single-earner households more likely to show a gap between their level of needs and their preparation for later life.

• 소성∙가공
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• 제12권6호
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• pp.536-541
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• 2003

In this paper, the rigid-viscoplastic finite element method is employed together with an iteratively force-balancing method to analyze a piercing and trimming process with a spring-attached die in hot former forging. An actual piercing and trimming process with a spring-attached die is investigated in detail and a generalized analysis model is proposed. A multi-stage hot former forging process is simulated under various spring constants. The analyzed results are discussed in order to investigate the effects of spring constants on the metal flow lines and the formed shapes. Then an optimal piercing and trimming process in hot former forging is devised.

• 정보관리연구
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• 제24권2호
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• pp.1-18
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• 1993

우리나라가 구소련(舊蘇聯) 과학기술(科學技術) 정보에 대해 직접적으로 수집하여 활용하고자 하는 사업(事業)을 추진한지는 불과 2년 정도 지났다. 구소련(舊蘇聯)과의 과학기술 협력을 진작시키기 위해 기술정보수집활동은 필수불가결하다. 그러나 상대 국가의 정치(政治) 경제적( 經濟的) 혼란, 기술정보에 대한 철저한 비밀정책(秘密政策), 광대한 영토에 산재한 6,000여개 연구기관(硏究機關) 등을 고려하면, 어느 한 개인(個人)이나 기관이 구소련(舊蘇聯) 과학기술 정보의 수집활동(蒐集活動)을 총체적으로 수행한다는 것은 불가능한 일이다. 그러므로 국가 차원에서 적극적인 전문인력(專門人力)과 예산의 지원이 있어야 하며, 아울러 관련(關聯) 기관간 상호(相互) 협력(協力) 체제를 강구해야 한다.

• 한국초전도ㆍ저온공학회논문지
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• 제25권4호
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• pp.45-49
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• 2023

CORC, which is being studied as one of the conductors for large currents, is manufactured by symmetrically arranging several strands of high-temperature superconducting wires on a cylindrical former. It allows current to flow evenly between wires and has the advantage of being manufactured in a multi-layer structure to increase current capacity. In order to apply CORC to AC power devices, it is necessary to review the material of the former, which is the frame around which the superconducting wire is wound. In the case of metal formers, they are difficult to apply because eddy currents are generated in the former, and they do not have the flexibility to be manufactured into coils by winding them with CORC. In this paper, we compare and analyze the magnetization loss caused by an external alternating magnetic field of Litz wire, which is being considered as a former material for CORC, with the results from formers made of other materials. In addition, we experimentally examine the effect of reducing magnetization loss due to an external magnetic field in CORC using a split wire made by dividing a high-temperature superconducting wire into two using an etching method, and in CORC made with a non-split wire.

• 보건교육건강증진학회지
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• 제9권1호
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• pp.39-47
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• 1992

This study was surveyed among 1136 respondent of high school girls in seoul from Feb. 6, till Feb. 22, 1992 for the purpose of analysing the smoking of high school girls and its factor. The data was analied by X²-test and Multiple Regression and shows the following. 1. Out of 1,136 respondent, the current smokers were found to be 176, 15.5% and the former smokers were 204, 18.0%. This implies that 23.5% of high school girls seoul have experience smoking. 2. For the first smoking time in both smoking group and former smokers, it shows that the third grade of middle school lead the lists. 36.9% (65) of the smokers and 37.3(75)of former smokers experienced the first smoking at that time. 70.5%(124) of the smoking group have the intention to stop smoking and the first reason of it is health problem, 65.6%(75). 3. For the type of the school the smoking rate rages from 2.7%(7) of literary part in day time to 25.3%(97) of vocational part in evening time and the rate of smoking experience shows from 9.9%(26) literary part in day time to 25.3%(97) of vocational part in evening time. This data show that literary part in day time has the lowst rate while vocational part in eveing time the highest rate. 4. Compared with non smoker group, smoking group and former smoking group spent more money (P<0.001) and felt dissatisfied with school life and didn't have good school records. 5. Smoking group and former smokers have more boy friends than non smoking group and in most cases their boy friend have smoking habits (P<0.001) and it is the same with their gril friend (P<0.001). 6. Compared with non smoker group, smoking group and former smokers lack of their parents' interest (P<0.001). But whether it is strict or free there is little difference among the three group. 7. For smoking group and former smoking group, in most cases their parent, brother and sister tend to smoke and especially their sisters' smoking has much influence on their smoking in comparison with non-smokers. 8. Compared with non-smoker group, smoking group and former smoking group tend to think less of the harm of smoking. In regard with health problem, more smoking group and former smokers think that smoking can relieve the stress (P<0.001), and more non-smokers know that when a pregnant woman smokes, it can cause the lack of supply of Oxygen{P<0.01). 9. Smoking group and former smoking group have more positive attitude towards smoking than non-smokers and tend to agree to their boy and girl friends' smoking(P<0.001).

• 한국정밀공학회지
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• 제20권4호
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• pp.29-38
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• 2003

This paper deals with an automated computer-aided process planning and die design system with which designer can determine operation sequences even after only a little experience in process planning and die design of multi former-bolt products by multi-stage former working. The approach is based on knowledge-based rules, and a process knowledge base consisting of design rules is built. Knowledge fur the system is formulated from plasticity theories, empirical results and the empirical knowledge of field experts. Programs for the system have been written in AutoLISP for AutoCAD with a personal computer. An attempt is made to link programs incorporating a number of expert design rules with the process variables obtained by commercial FEM softwares, DEFORM and ANSYS, to form a useful package. The system is composed of four main modules. The process planning and die design module considers several factors, such as the complexities of preform geometry, punch and die profiles, specifications of available multi former, and the availability of standard parts. It can provide a flexible process based on either the reduction in the number of forming sequences by combining the possible two processes in sequence, or the reduction of deviation of the distribution and the level of the required forming loads by controlling the forming ratios. The system uses 2D geometry recognition and is integrated with the technology of process planning, die design, and CAE analysis. The standardization of die parts for multi former-bolt products requiring a cold forging process is described. The system developed makes it possible to design and manufacture multi former-bolt products more efficiently.