• 콘크리트학회논문집
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• 제11권6호
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• pp.3-12
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• 1999

The larger, loftier and more highly strengthened the recent structures become, the greater attention is paid to the problem of thermal crack occurrence associate with hydration heat. As one of methods to solve the problem, a care has been taken to the improvement of construction such as the application of pre-cooling or pipe-cooling, adjustment of concrete block size, concrete placement timing, joint arrangement and so on. But it is expected that a proper selection of cement shall additionally contribute to the control of thermal cracks. In this study, thus, we selected 4 types of cements such as Type V for anti-sulphate, blast furnace cements (slag content of 45% and 65% respectively)and ternary blended low heat cement, and carried out mock-up tests. In every assigned time, temperatures and thermal stresses were measured and calculated from raw data. As a result of measurement, it was found that the magnitude of hydration heat is in order of blast furnace slag cement. Type V and ternary blended low heat cement. Results of thermal stresses were same as the order of temperature. In addition, thermal stresses calculated from the data of strain gauges showed almost similar to those measured from effective stress gauges only when strain values were adjusted properly in accordance with initial time of stress appearance. Theoretical results agreed well with the measured values comparatively, but showed slight differences. It is inferred that these differences shall be reduced if more tests capable of evaluating thermal characteristics of concrete are carried out.

• 한국어병학회지
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• 제15권2호
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• pp.65-75
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• 2002

This study was performed to know the effects of stress induced by the daily fluctuation of water temperture from 18$^{\circ}C$ to 25$^{\circ}C$ up and down for 30 days on the defence mechanism of olive flounder. Puralichthys olivaceus. To make clear the temperature stress on the defense mechanism of the tested fish. several factors of immune response such as counting of leucocyte appearance in peripheral blood, phagocytic activity in whole blood cells, nitroblue tetrazolium(NBT) reduction, chemiluminescence(CL) response, and lysozyme activity were investigated at 28 days after giving the change of water temperature. The fish was controlled under the none feeding condition during experimental period. Mortality of the tested fish was rapidly increased up to 22% within the first one week of the experimental period without any additional stress factors. The number of neutrophil of peripheral blood in the tested group was significantly higher than the control group at the 2nd week. but the number of lymphocyte was significantly lower than the control group at the 1st and 3rd day of the experimental period. respectively. In the NBT reduction test, the activity of macrophage in the control group fish was the highest on the 7th day while that in the tested group was on the 3rd day. Also. the phagocytosis of tested group against formalin killed cells was retarded compared with the control. CL response of the tested group was significantly lower from 2nd to 5lh day of the experimental period than the control. 'The lysozyme activity of tested group was remained higher during the experimental period than the control. Even though the tested fish showed different results in some non-specific factors of immune respceses between tested and control group fish, olive flounder seems highly adaptable in repealed water temperature change in condition after one week under the given temperature fluctuation range.

• 한국표면공학회지
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• 제51권1호
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• pp.62-70
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• 2018

Sulfamate plating solution containing a small amount of chloride bath was fabricated to study the properties of the electrodeposited Ni thin films. Effects of the changes of current density and additive concentration on current efficiency, residual stress, surface morphology and microstructure of Ni thin films electrodeposited from Ni sulfamate-chloride baths were investigated. The current efficiency was measured to be more than about 95%, independent of the changes of current density and saccharin concentration in the baths. Residual stress of Ni thin film was appeared to be the compressive stress modes in the range of $5{\sim}30mA/cm^2$ current density. Maximum compressive stress was observed at the current density of $10mA/cm^2$. Compressive stress values of Ni thin/thick films were increased to be about -85~-100 MPa with increasing saccharin concentration from 0 to 0.0195 M(4 g/L). Surface morphology was changed from smooth to nodule surface appearance with increasing the current density. Smooth surface morphology of Ni thin films electrodeposited from the baths containing saccharin was observed, independent of the saccharin concentration. Ni thin/thick films consist of FCC(111), FCC(200), FCC(220), FCC(311) and FCC(222) peaks. It was revealed that the FCC(200) peak of Ni thin films is the preferred orientation in the range of $5{\sim}30mA/cm^2$ current density. The intensity of FCC(200) peak was gradually decreased and the intensity of FCC(111) peak was increased with increasing saccharin concentration in the baths.

• 대한간호학회지
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• 제13권3호
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• pp.75-85
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• 1983

This study was done to research the relationship between general characteristics and stressor, stress situation, Nursing Intervention of pregnant woman. The subjects for this study were 70 pregnant woman from 3 clinics of Obstetrics and Gynecology located in J city. The data was collected through questionaires which was developed by Norman J. Chestnut. The content of the questionaire consist of following 3 categories; (1) stressor (2) stress situation (3) Mental and Physical support of husband. Analysis of data was done by use percentage, x²-test. (through EDPS) The findings of this study are as follows; 1, Stressors of pregnant woman are stresses associated with fetus, socioeconomic problem, herself, delivery, abortion and prematureity, husband, change of appearances, management of home, a woman's parents-in-law. Stress situations of pregnant woman are when she is doing on the heavy management of home, limit of life, socioeconomic discomfort, taking medicine, difficult relationship with a woman's parents-in-law, being sign of abortion and prematurity, her physical discomfort, family desire of delivery of son baby. 2. Husband's mental support that pregnant woman desired are careful husband's role, More love and interest about pregnant, cooperation of child reaing, maintenance of healthy life, understaning of diffical pregnancy, early return home, giving up drinking, positive feeling about changed appearance, unconcern about sex of fetus. And husband's mental supports that pregnant woman desired are cooperating of homework and childrearing, limit of intercouse, release behavior of pregnant woman's physical discern-fort, a walk, behavior with pregnancy together, socioeconomic stability. 3. Stressor of pregnant woman was significant with education, number of son, economic status, personality of husband, dowelling. (P<.05) And stress situation of pregnant woman was significant with personality of husband, dwelling, husband's desired sex .of baby. (P<.05) 4. Husband's mental and physical supports that pregnant woman desired was significant with number of daughter. (P<.05).

• Food Science and Biotechnology
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• 제17권4호
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• pp.713-717
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• 2008

In the present study, chronic effects of the hot water extracts of walnut seed (Juglans regia L.) (WSE) and Nelumbo nucifera seed (NSE) were investigated in mice exposed to 2 hr of restraint stress each day for 4 weeks. Corticosterone levels in serum were significantly increased in the vehicle-treated stressed group ($25\;{\mu}g/dL$) compared to that in the control group ($13\;{\mu}g/dL$). This stress induced gastric redness and lesions. However, treatment with WSE and/or NSE significantly protected the stomach from this lesion by 50-60% compared to that in the vehicletreated group. In the amygdala, the administration of WSE and/or NSE also reduced the immediate early gene (c-fos) expression by 70-90% vs. the vehicle-treated group. These suggest that WSE and/or NSE may reduce the appearance of symptoms induced by stress and these materials are useful as anti-stress foods, as natural products tend to be relatively safe compared to chemical products.

• Structural Engineering and Mechanics
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• 제47권1호
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• pp.59-73
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• 2013

The Xiaolan channel super large bridge is unique in style and with greatest span in the world with a total length of 7686.57 m. The main bridge with spans arranged as 100m+220m+100m is a combined structure composed of prestressed concrete V-shape rigid frame and concrete-filled steel tubular flexible arch. First of all, the author compiles APDL command flow program by using the unit birth-death technique and establishes simulation calculation model in the whole construction process. The creep characteristics of concrete are also taken into account. The force ratio of the suspender, arch and beam is discussed. The authors conduct studies on the three-plate webs's rule of shear stress distribution, the box girder's longitudinal bending normal stress on every construction stage, meanwhile the distribution law of longitudinal bending normal stress and transverse bending normal stress of completed bridge's box girder. Results show that, as a new combined bridge, it is featured by: Girder and arch resist forces together; Moment effects of the structure are mainly presented as compressed arch and tensioned girder; The bridge type brings the girder and arch on resisting forces into full play; Great in vertical stiffness and slender in appearance.

• 융합정보논문지
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• 제9권10호
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• pp.264-271
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• 2019

현재 청소년들은 대중매체의 근접성에 의한 외모적 아름다움을 중요시 하고 있다. 따라서 피부에 발생하는 여드름은 중증의 질병은 아니지만 잘못 관리하면 안면부에 흉터와 자국을 남기게 되고 이는 학생들의 자신감을 상실시키고 우울증과 스트레스를 동반한다. 이에 본 연구에서는 여드름 피부가 청소년의 스트레스, 우울증, 자아존중감에 어떠한 영향을 미치는 가를 분석하여 여드름을 단순한 피부질환의 하나로 생각할 것이 아니라 정신건강에도 밀접한 관계가 있음을 인지하고 여드름 피부를 관리하는데 좀 더 효과적이며 피부를 관리하는 기초자료로 활용하고자 3가지 가설을 수립하였다. 그 결과 중학생의 여드름 발생이 스트레스와 우울증에 정(+)의 영향을 미치는 것으로 나타나 여드름 피부관리는 표면적 관리가 아닌 정신건강에 필요한 관리로 사료된다.

• 디지털융복합연구
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• 제17권8호
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• pp.447-452
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• 2019

미적(美的) 욕구표현의 수단으로 현대인은 외모 치장에 많은 시간과 경제적 투자를 하고 있으며, 외모의 대부분을 차지하는 헤어미용 중 멋 내기 모발 염색을 많이 애용하지만 이에 따른 모발손상도 심각한 상태이다. 그러므로 모발손상을 최소화하면서 멋 내기를 유도할 수 있도록 산화염모제에 따른 모발 인장강도에 관한 연구를 하고자 한다. 연구결과 대조군과 8N-10N 실험군 간 최대하중, 최대 인장강도, 최대 신장률, 파단 하중, 파단 강도, 파단 신장률, 평가구간에 따른 최대 모듈러스 및 접선 계수 등은 서로 유의적인 차이를 보였다. Strain 구간에 따른 최대 모듈러스와 접선 계수인 tangential modulus는 대조군과 실험군 간 차이가 있음에도 일정하게 증가하거나 감소하는 경향이 뚜렷하게 나타나지 않았다. 따라서 본 연구는 산업체 현장에서 애용되고 있는 고명도(高明渡) 멋 내기 산화염모제 시술을 통한 모발손상과의 상관관계를 데이터로 규명함으로써 헤어미용 교육 자료로서의 활용 및 헤어디자이너의 올바른 산화염모제 선택을 위한 응용자료를 제공하고자 한다.

• 보건교육건강증진학회지
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• 제3권1호
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• pp.43-55
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• 1985

The recent problems of adolescents are leading us to amphasize school mental health program. Therefore, for the first step of that program, this study was attempted to find out the students' daily life stress, their adaptation beharior to resolve that stress, and their self-concept which has an effect on that beharior, to analyze the relationship among those three variables, and to provide basic data which help maintain and promote students' adaptability and mental health. The subjects were 4 classes each grade, 743 students who were chosen as a sample subject among the total of 3,250 students of a junior girls' school in Seoul by stratified sampling method. The Oquestionnair surrey was done from April 1, 1985 to April 6, 1985. The instruments were (1) a part of Junghoon chois' perceptual Orientation Scale for measuring self-perception of students, (2) Rosenberg's Questionnair for measuring students' evaluation of self-esteem, (3) modified Bell's Adoptive Behavior Questionnair, and (4) the Measuring scale for stress developed by the investigator. The collected data were analyzed by using descriptive statistics, x²-test, t-test, ANOVA, and Pearsons' Correlation. The results are summarized as follows: 1. The range of mean score of self-concept, stress, and adaptation beharior is 1-5 respectively. The mean score of self concept was 3.45. The mean score of stress was 2.53, and the degree of stress was in order of the problem of study and grade marks, girl friend, appearance, and relaxation. The subjects preferred effective long-term adaptation method (Mean=2.81) to ineffective short-term adaptation method. (Mean=2.47) 2. The self-concept had the highest degree when students were 1st grade, in good health condition, taking high grade marks, both parents existing, fathers' educational level being above college, and being in high economic status. The degree of stress was significantly high when students were 3rd grade, in poor health condition, having low grade marks, being in poor economic status, and fathers' educational level being under elimentary school. In relation with adaptation method, 1st grade students used more sbort-term and long-term method, and when students had high grade marks, being in high economic status. they used more long-term adaptation behavior. 3. Two Hypotheses of this research were tested: Hypothesis 1. "The higher the students' self-concept is, the more they use long-term adaptation method." was accepted. (r=.2482, p<.01) (t=-4.99, p<.001) Hypothesis 2. "The higher the students' stress is, the more they use short-term adaptation method." was accepted. (r=.2897, p<.01) (t= -7.51, p<.001) In conclusion, a person in charge of school health can help students to adapt effectively by planning and implementing methods which highten their self-concept and lower their stress. But because the correlation among self-concept, stress and adaptation behavior was at a low level, I think that the study, which confirm the relationship of those three variables, is needed.

• 치위생과학회지
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• 제15권5호
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• pp.527-535
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• 2015

조사 대상자인 235명의 대학생들은 27.2%가 치아우식증 치료 경험이 있고 48.1%가 치주질환을 치료한 경험을 가지고 있었다. 46.4%는 정기적인 구강검진을 하고 54.0%는 스켈링 경험이 있으며 58.3%는 칫솔질 교육경험이 있는 것으로 조사되었다. 그리고 46.4%가 구강보조용품으로 치실을 사용하였고 66.4%는 일일 3회 칫솔질을 하는 것으로 조사되었으며 73.6%가 칫솔은 2~3개월마다 교체하는 것으로 조사되었다. 조사 대상자인 235명의 대학생 스트레스를 항목별로 조사한 결과 성격에 대한 스트레스가 $3.40{\pm}0.73$으로 가장 높았다. 그 중 '뭔가를 하는 것이 귀찮다'는 항목이 $3.73{\pm}1.20$으로 가장 높았고, '다른 사람의 문제에 대하여 걱정하였다'가 $2.22{\pm}1.15$로 가장 낮았다. 여학생은 외모와 성향, 가족, 대인관계에 대한 스트레스가 남학생보다 높은 것으로 나타났고, 남학생은 학업에 대한 스트레스가 여학생보다 높은 것으로 나타났다. 조사대상자 235명의 대학생 중 치아우식증을 가지고 있거나 치주질환을 가지고 있는 경우 스트레스가 평균 이상인 것으로 나타났고 치석제거 경험이 있거나 칫솔질 교육 경험이 있는 경우 즉 예방관리를 하는 집단이, 예방하지 않는 집단에 비하여 스트레스가 평균 이하인 것으로 나타났다. 본 연구 결과 대학생의 스트레스는 구강건강을 위해 치료를 하는 단계에 이를 때면 이미 스트레스가 상승하고 예방적 관리가 잘 이루어질 때는 스트레스 감소하는 것을 알 수 있다. 다시 말해 이미 구강병이 발생하여 치료 경험이 있는 경우에는 스트레스 수준이 더 높아지므로 구강질환 예방을 위한 대책이 시급하다는 것을 알 수 있다. 또한 대학생의 구강건강증진을 위해 구강질환 예방에 대한 체계적인 교육 프로그램을 지속적으로 운영하고 활성화해야 할 것으로 생각된다.