• 제목/요약/키워드: Long-term period

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파랑 통계자료의 특성과 신뢰성 검토 (The Characteristics of Wave Statistical Data and Quality Assurance)

  • 박종헌
    • 동력기계공학회지
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    • 제13권2호
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    • pp.63-70
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    • 2009
  • This paper discusses the influence on long-tenn predictions of the ship response in ocean by using the Global Wave Statistics data, GWS, and wave information from the remote sensing satellites. GWS's standard scatter diagrams of significant wave height and zero-crossing wave period are suggested to be corrected to a round number of 0.01/1000 fitted with a statistical analytic model of the conditional lognormal distribution for zero-crossing wave period. The GEOSAT satellite data are utilized which presented by I. R. Young and G. J. Holland (1996, named as GEOSAT data). At first, qualities of this data are investigated, and statistical characteristic trends are studied by means of applying known probability distribution functions. The wave height data of GEOSAT are compared to the data observed onboard merchant ships, the data observed by measure instrument installed on the ocean-going container ship and so on. To execute a long-tenn prediction of ship response, joint probability functions between wave height and wave period are introduced, therefore long-term statistical predictions are executed by using the functions.

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재학 중 현장실습과 취업 후 직무만족 간의 관계에 관한 연구: 장·단기현장실습의 비교 (A Study on the Relationship Between on-site Training During the School Year and Job Satisfaction after Employment: A Comparison between Short-term and Long-term on-site Training)

  • 김성희;이상곤
    • 공학교육연구
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    • 제21권1호
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    • pp.44-55
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    • 2018
  • The purpose of this study is to investigate the relationship between post - employment job satisfaction and both short-term (4-12 weeks) and long-term (12+weeks) on-site training. For this purpose, 405 graduates who had completed on-site training (205 short-term, 200 long term) during the school year were surveyed. The results of the comparative analysis of both short-term and long-term on-site training participants are as follows: In both short-term and long-term on-site training, it was found that on-site performance during the school year did not directly affect post-employment job satisfaction. In the case of short-term on-site training participants, job match and organizational commitment were found to have no mediating effect on the correlation between on-site training performance and job satisfaction. On the other hand, in the case of long-term on-site training participants, the analysis showed that job match and organizational commitment had mediating effects on the correlation between on-site training performance and job satisfaction. These effects are not solely attributable to differences in duration of training; the differences in operating systems and the degree of preparation derived from these systems also affect the level of on-site training for students, businesses, and schools. This paper summarizes these findings and suggests the following improvement plans for on-site training in the future: First, short-term on-site training is required to establish a systematic basis in order to enhance students' preparedness level. Second, both short-term and long-term on-site training should improve the skills and field understanding for students' majors through systematic quality management during the training period. Third, it is necessary for universities to increase expectations and quality of short-term on-site training for all involved while simultaneously reducing the gap between educational goals and practice in this field.

악교정술전후의 설위 및 설골의 위치변화와 회귀현상에 대한 연구 (A STUDY OF RELAPSE AND POSITION OF HYOID BONE FOLLOWING ORTHOGNATHIC SURGERY)

  • 이상한
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제13권4호
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    • pp.476-490
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    • 1991
  • Although various technical details of the surgical procedures have been improved, Skeletal relapse is the most noteworthy complication of orthognathic surgery. It seems to be an imbalance of the perioral muscular groups resulting from changes in the cavitas oris propria after surgery. Among other factors, it is widely known with the changes of tongue posture, as indicated by the hyoid position. Ten patients that had undergone mandibular setbacks by way of Modified Obwegeser method were evaluated retrospectively. The serial cephalometric films were taken preoperatively, immediately postoperatively, after removal of IMF, and at a subsequent long-term follow-up period. The cephalometric evaluation of tongue posture were based on stable craniofacial landmarks. The relation between the 2-dimensional changes of tongue posture and hyoid position and the relapse of mandibular setback are discussed. Anatomic changes that were found to accompany such setback are as follows. 1.There are 2 cases of relapse in 10 patients at long-term follow-up(20%) 2.The tongue was moved posteriorly and its size was reduced anteriorly and posteriorly at immediate postoperative change and then the mandible shifted slightly toward the preoperative position, but the long was adapted to its new environment due to changing the position of its posterior part, and also the hyoid that moved posterioly and inferiorly was stabilized sightly posteriorly than its original position. 3.On the distance change of the suprahyoid muscle, the distance of P-H, ST-H was increased at immediate postoperative change(p<0.01) and decreased at IMF period(p<0.001), but the distance of H-Me, H-Ge was slightly decreased at IMF and long-term period(p<0.05). 4.On the width change of the pharyngeal air way, the width of the upper part of the pharyngeal space was lightly contracted at IMF and long-term period(p<0.05). 5.On the relation between mandibular setback and tongue posture and hyoid position, the significant correlation was found between the changes of some parts of mandibular setback and those of tongue posture, and not found those of hyoid position.

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효율성과 무지, 그리고 환경피해 - 석면 사용과 악성중피종 발생의 장기관계 - (Efficiency, Ignorance, and Environmental Effect - long-run Relationship between Asbestos Consumption and the Incidence of Mesothelioma -)

  • 손동희;전용일
    • 자원ㆍ환경경제연구
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    • 제26권3호
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    • pp.287-317
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    • 2017
  • 경제성장과정에서 석면을 활용해왔지만, 석면이 치명적인 환경성질환을 유발하는 1급 발암물질로 지정되면서 전 세계적으로 엄격한 석면사용규제 조치를 실시하고 있다. 석면노출과 환경성질환의 발현 간에 수십 년에 걸친 장기 잠복기가 존재한다는 특성을 고려하여, 한국의 석면 소비량과 악성중피종 발병 간의 시차를 분석하고 장기관계를 추정한다. 이와 함께, 한국에 비해 상대적으로 석면규제가 오랜 기간 이루어지고 장기시계열 자료를 갖춘 영국과 미국을 대상으로 한 비교분석도 병행한다. 시차분석에서는, 3개 국가 모두에서 30년 이상의 장기시차가 존재할 때, 석면 소비와 악성중피종 발병 간의 교차상관성이 높은 것으로 나타난다. 또한 변수간 장기시차가 존재할 경우 석면 소비량과 악성중피종 발병 간에 장기균형관계가 존재한다. 그리고 시차분포모형을 활용한 결과, 석면 소비량이 장기시차를 두고 악성중피종에 유의한 정의 영향을 미치고 있다.

인공생장호르몬을 사용하여 생산되는 우유의 안전성에 대한 미국소비자들의 관심에 관한 연구 (Consumer Concerns for Safety to Cow's Milk Produced by Biotechnology in the United States)

  • 유소이
    • 대한가정학회지
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    • 제38권1호
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    • pp.59-73
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    • 2000
  • The purposes of this study were to determine the factors that influence consumer concerns for safety to cow's milk produced using food-related biotechnology and to find the similarity and difference among concern factors relating short-term and long-term risk perception. Telephone interviews were conducted and the data were collected from households(n=1,466) nationwide in the U.S. And the data were analyzed by probit model and LIMDEP softare package. The data demonstrated that consumers were concerned about food safety from consuming milk produced using food-related biotechnology. The concerns were found to be influenced by demographic factors(gender in short-term, gender and age in long-term) as well as psychological aspect such as outrage(heard about bGH, milk belief about naturalness, expected benefit in short-term, heard about bGH, expected benefit in long-term) and attitudinal factors(animal rights group, locus of control in short-term, animal rights group, cancer history, locus of control in long-term). The results suggest that consumers have concerns for safety to cow's milk produced by biotechnology and the most factors influencing consumer concerns were similar between short-term and long-term period, though a few factors such as cancer history, milk belief about naturalness and age were different.

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장기해고노동자의 심리적 경험에 대한 질적 연구: 노동조합 조합원을 대상으로 (A Qualitative Study on Long Term Laid off Workers' Psychological Experiences: Focusing on labor Union Members)

  • 임정선
    • 한국콘텐츠학회논문지
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    • 제15권7호
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    • pp.228-243
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    • 2015
  • 본 연구에서는 노동조합 조합원인 장기해고노동자들이 해고와 이후 실업기간을 어떻게 경험하는지 그 변화과정을 현상학적 방법으로 분석하였다. 연구대상자는 평균해고 기간이 8년 4개월인 남성 해고노동자로 5명을 심층 면담하였다. 해고 당시의 심리적 경험, 해고 이후 지속적인 심리적 또는 신체적 변화, 현재 상태, 해고기간 동안의 대처방법 등을 반구조화 질문지에 근거하여 심층 면담을 진행하여 자료를 수집하였다. 이를 분석한 결과 21개의 하위 주제와 이를 포괄하는 5개의 상위주제를 구성하였다. 중요상위주제는 '해고 당시와 이후의 감정과 인식', '해고가 장기화되면서 생기는 증상과 변화', '장기화된 현재의 상태', '사회적 인식에 대한 양상', '해고에 대한 대처' 이었다. 상위주제와 하위범주에 대하여 기술하고 이와 관련된 장기해고노동자의 경험을 구체적으로 기술하였다. 마지막으로 장기해고노동자의 변화 및 경험을 선행연구를 바탕으로 논의하였다.

양성 신경교종의 감마나이프 방사선수술 - 장기 추적 결과 - (Gamma Knife Radiosurgery for Low Grade Glioma - Long-Term Follow-up Results -)

  • 천세명;임영진;임언;김태성;김국기;이봉암
    • Journal of Korean Neurosurgical Society
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    • 제30권sup2호
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    • pp.273-280
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    • 2001
  • Objectives : The purpose of this study is to assess the long-term outcome and delayed complications of Gamma Knife radiosurgery for low grade glioma(LGG). Methods : Among 31 patients of LGG who had been treated by using Leksell Gamma Knife between March 1992 and December 1996, we could follow up more than 5 years(range 5-9 years) in 17 patients and evaluated their clinical feature, changes of tumor volume and post-radiosurgical complications. Results : During the mean follow-up period of 7.6 years, the tumor was decreased in 5 patients(29.4%), unchanged in 4(23.5%), increased in 4(23.5%) and recurred in 4(23.5%). The tumor control rate was 52.9%(9/17). We have experienced eighteen postradiosurgical complications in 10 patients(58.8%). Early complication was none and delayed complications included radiation necrosis with cyst in ten cases, bleeding in five, radiation-induced edema in one and malignant transformation in one. Two patients ultimately died as a result of tumor progression during the follow-up period. The mortality rate was 11.7%. Conclusion : Gamma Knife radiosurgery may be useful as an adjunctive therapy for small volume, deep-seated LGG. Although radiosurgery can effectively prevent growth of solid tumor, several delayed complications such as radiation necrosis, cyst formation, bleeding or malignant transformation can develop during the long-term followup period. Because of the possible slow growth rate of LGG and development of the delayed complications, the long-term efficacy of radiosurgery requires further analysis.

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이탄의 장기압밀특성에 관한 연구 (Studies on the Long-term Consolidation Characteristics of Peats)

  • 김재영;주재우
    • 한국농공학회지
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    • 제31권1호
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    • pp.106-116
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    • 1989
  • This study aims at scrutinizing the long4errn consolidation characteristics of peats sampled at three different regions of Chonbuk province. The standard consolidation test and the single load consolidation test were performed about these samples and especially in case of the latter the loading period was 350 days. The main condusions analyzed are as follows. 1. Void ratio showed much greater values than that of the general clay and was decresed greatly according to the increase of the load. 2. In case of the relationship between the sefflement and the long-term settlement time the rate of settlement increment became great according to the increase of the load step and the long4erm settlement became linely proportional to the logarithm of time alter 10 minutes. 3. The linear correlation was showed between the long4erm settlement time and the void ratio and therefore equations by regression analysis were derived in order to estimate the long-term settlement The slope of straight lines increased according th the increase of the load step and secondary consolidation coefficients ranged from 0.04-0.27. 4. The secondary consolidation coeffcient became linealy proportional to the compression index and the ratio of Ca to CC was 0.072. 5. The period required in ending the primary consolidation was about 10 minutes and alter that the secondary consolidation coefficient appeared to have constant value. Therefore the secondary consolidation coefficient was judged to be used as a significant factor in estimating the long4erm settlement. 6. In case of the single load consolidation test the secondary consolidation coefficient showed the tendancy increasing according to the increase of the consolidation pressure.

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미슐랭 가이드 스타 레스토랑에 대한 기대가치가 방문의도에 미치는 영향 (The Impact of Expected Value of Michelin Guide Star Restaurants on Visit Intention)

  • 최성룡;윤성현
    • 한국프랜차이즈경영연구
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    • 제15권2호
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    • pp.77-87
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    • 2024
  • Purpose: South Korea is one of the markets where diverse and innovative cuisines are being tried. Therefore, the expectations for Michelin star restaurants in South Korea are high. The expected value of a Michelin star restaurant consists of both hedonic and utilitarian aspects of the dining experience. These consumer expectations affect visit intention. Research design, data, and methodology: The survey period was from October 10, 2023 to October 18, 2023, and 302 copies were used for hypothesis verification. Result: Hedonic expected value was found to have a significant positive influence on short-term and long-term visit intention, but had no significant effect on mid-term visit intention. Utilitarian expected value was found to have a significant positive influence on short-term and mid-term visit intention, but did not appear to have a significant effect on long-term visit intentions. Short-term visit intention was found to have a significant positive influence on mid-term visit intention, and mid-term visit intention was found to have a significant positive influence on long-term visit intention. Conclusions: The theoretical implications are restaurants need to utilize third-party certification, such as the Michelin Guide. The practical implication is that Michelin star restaurants should provide expected value to increase short-term visit intention.

폐경 전 여성의 모유수유기간과 골밀도와의 관련성 연구 (The Relationship of Bone Mineral Densities and Period of Breast feeding in Premenopausal Women)

  • 이은남;이은옥;이광혜
    • 대한간호학회지
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    • 제30권1호
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    • pp.29-38
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    • 2000
  • To determine whether personal history of lactation in premenopausal women influence bone mineral density, a cross-sectional study was conducted. One hundred eighty-four premenopausal women were selected from women who had been checked for bone mineral density by dual energy x-ray absortiometry in lumbar spine, femoral neck, Ward's triangle, and trochanteric site at general hospitals in Seoul and Pusan. They completed a questionnaire including life style factors and reproductive history. In the data analysis, Pearson correlation coefficients were used to test any association between individual variables and bone mineral density and a statistical comparisons between long term lactation(>24 months) and short term lactation(<24 months) were made by one way analysis of covariance. The results were summarized as follows: 1) There was no significant difference in the bone mineral density of the lumbar vertebrae in premenopausal women between the long term lactation group(>24months) and the short term lactation group(<24months). 2) There was no significant difference in the bone mineral density of the femur neck, Ward's triangle, and trochanteric site in premenopausal women between the long term lactation group (>24months) and the short term lactation group (<24months). Considering these results, we suggest prospective studies that measure bone mineral density before and after, in addition to those during lactation. We also suggest the further study with premenopausal women less than 35 who have achieved peak adult bone mass.

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