• Journal of the Korea Concrete Institute
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• v.14 no.5
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• pp.789-795
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• 2002

To evaluate the bind rate and behavior of two types chloride ion-one is the chloride ion added in mixture when un-washed sea sand is used as fine aggregate, one is the chloride ion admitted in the new version of concrete standard specification, pore solution extracted in cement paste were analyzed. The results are follow. 1 As passing the time, the chloride concentration in the pore solution decreases with the Increase in the chloride content absorbed by the hydrate products. As compared with chloride contents in mixing water, the bound ratio of chloride at 49 days is 64∼90％. 2. The bound ratio of chloride in cement paste considering evaporable water as pore solution is obtained. In case of Pl∼P3(added chloride content wt of cement 0.046∼0.16 ％), the bound ratio of chloride is 91.8∼93.5 ％. P4(added chloride wt of cement 0.3％) is 89.1％, but P5(added chloride wt of cement 0.617％) bound is only 77％. 3. The bound ratio of chloride to wt of cement is 0.015∼0.475％ with adding chloride. In case chloride added over 0.091 ％ wt of cement, the bound chloride content increases 1.7∼1.8 times in spite of added chloride increase twice. The bound ratio of chloride to wt of cement decreased with the increase in the chloride content. 4. The more increase added chloride content, the more increase the bound ration of chloride. But the absolute value of chloride content in pore solution increased.

• Journal of The Korean Association For Science Education
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• v.32 no.5
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• pp.866-878
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• 2012

The Natural Science High School is specialized in vocational education or training related to natural sciences such as biology or chemistry. Therefore, natural science high school students are expected to possess a high level of science learning motivation. This study aims to explore natural science high school students' level and structure of science learning motivation by comparing students in general high school. One hundred ninety three students from a natural science high school and 208 from a general high school participated in this study. We administered a questionnaire that consisted of seven science motivation components: 1) career motivation; 2) science grade motivation; 3) understanding the relevance of scientific knowledge; 4) need for learning science; 5) self-determination; 6) self-efficacy; and 7) attitudes toward science class. We employed independent t-test, path analysis, bivariate correlation, and stepwise multiple-regression for the statistical analyses. Our findings illustrated that the natural science high school students' levels on all seven variables were significantly lower than the general high school students.' The path analysis illustrated that career motivation and science grade motivation had relatively stronger influence on self-determination and self-efficacy in the natural science high school student sample than in the general high student sample. The explanatory powers of four independent variables (career motivation, science grade motivation, understanding the relevance of scientific knowledge, and need for learning science) predicting self-determination and self-efficacy were 30% higher in the natural science high school student sample than in the general science high student sample. These results suggested that natural science high school students' science learning motivation may be easier to change by extrinsic motivations such as career and science grade motivation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.1-7
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• 2017

This study investigates the high-frequency heat treatment characteristics with the distance between a coil and SCM440 parts for an automobile. Global automobile makers are focusing on research to develop high-performance automobiles with improved fuel efficiency and lower emissions in accordance with consumer demand and environmental policies. However, most research on high-frequency heat treatment has been experimental, and it is very difficult to obtain high-frequency heat treatment conditions for a specific product. Therefore, all the conditions of high-frequency heat treatment except the distance between a coil and SCM440 parts were kept the same. As a result, the optimized distance between the coil and SCM440 parts was observed to be 1-2 mm. When the distance between the coil and SCM440 parts was over 3 mm, the effective case hardness depth and total case hardness depth did not satisfy the standards.

• Journal of agricultural medicine and community health
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• v.30 no.1
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• pp.29-38
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• 2005

Objectives: Hypertension is the most important risk factors for the cerebrovascular diseases, and also for coronary heart diseases, it is therefore very important that the people have a knowledge on nature of hypertension and it's high risk in order to prevent and detect the hypertension as early as possible. Methods: This study was done to find out the knowledge on hypertension of 434 parents of elementary school students from Kimjae city, Jonbuk province, they were parents in grade 4, 5 and 6 attending two elementary schools. The survey took 10 days from November 20 to November 30, 2003. Results: first, The highest correct answer(94.5%) was "obesity is risk factors for hypertension", followed by "hypertension is closely related with hereditary factors(91.0%) and "high sodium intake is associated with high blood pressure"(85.7%). The lowest correct answer(77.4%) was the classification of blood pressure level between normal and high. Second, Rate of blood pressure measurement for fathers was 53.7% and 54.8% in mothers. Awareness of own blood pressure by fathers was 84.1 %, while 91.1% by mothers. Third, According to blood pressure level reported by parents, fathers with normal blood pressure was 59.2%, high normal blood pressure was 12.2%, while hypertension was 28.6%. It revealed that prevalence of hypertension of fathers was higher than mother (normal: 74.5%, high normal: 7.7%, hypertension: 18.2%). Conclusions: From the results of this study, it is important to strengthen the health education about hypertension for community people and also school students.

• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.625-636
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• 2017

The purpose of this study is to compare the differences in the operation form of science academy, science high school, and ordinary high school. We tried to find what kinds of variables differ in operation form based on the perception of the beneficiaries. For this purpose, 288 beneficiaries were surveyed. The groups were divided into three groups according to the high school they graduated from and then the differences among the groups were compared. The results are as follows. First, as a result of comparing the operation form according to high school using the most similar system design, it was confirmed that there are differences in curriculum and teacher variables. Second, as the result of analyzing the perception of curriculum and teacher professionalism based on the education experience of the beneficiary, the satisfaction for science academy was higher, but the satisfaction for science in ordinary high school was lower. Third, the key variables showing the differences in the operation forms between science academy and science high school were the learning contents, learning process and learning environment. The results of this study are expected to be used as basic data for future improvement of gifted education curriculum.

• Proceedings of the KSCN Conference
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• 2003.11a
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• pp.1079-1079
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• 2003

최근 노인인구의 증가와 함께 식생활의 변화에 의해 사망원인의 변화가 일어나고 있다 한국인의 주요 사망원인 중 뇌혈관 및 심장질환 등 순환기계 질환에 의한 사망이 증가하고 있는 추세이며, 심장순환계 질환의 위험요인인 고혈압의 이환률도 65세 이상 노인에게서 증가하고 있다. 고혈압은 만성질환으로 산화적 스트레스를 증가시키는 질환이므로 본 연구에서는 건강한 노인과 고혈압 노인의 체내 항산화 영양상태를 비교하기 위해 울산지역 50세 이상 노인을 대상으로 하였다. 대조군은 질환이 없거나 골다공증, 위장질환과 같은 기타 질환을 가진 사람 96명이었으며, 고혈압환자군은 고혈압을 가진 모든 질환자 118명이었고, 항산화 영양소 섭취나 혈장내 항산화 영양상태에 영향을 미치는 성별, 연령, 흡연 및 음주상태를 보정하여 비교하였다. 고혈압환자의 평균 유병기간은 6.1년이었으며, 항산화 비타민 섭취량은 비타민 A, retinol, $\beta$-carotene과 비타민 C 섭취량 모두 고혈압 유무에 따른 유의적인 차이가 나타나지 않았으나 고혈압환자의 섭취량이 높은 경향을 보였다. 한국인영양권장량과 비교한 결과 대조군의 비타민 A 섭취는 권장량의 86.2%, 고혈압환자군은 권장량의 103.0%를 섭취하여 고혈압군에서 유의적으로 높았고, 권장량의 75% 이하 섭취자의 비율은 대조군에서 46.9%, 고혈압군에서 41.5%로 조사되었다. 비타민 C 섭취는 대조군에서 권장량의 176.6%, 고혈압군에서는 189.0%로 나타나 질환의 유무에 관계없이 두 군 모두 권장량의 170%이상을 섭취하고 있었으나 권장량의 75% 이하를 섭취하는 사람의 비율이 대조군에서 13.5%, 고혈압군에서 17.0%로 고혈압군에서 높게 나타났다. 혈장 비타민 C의 농도는 대조군 15.3 mg/L, 고혈압환자 15.9mg/L, 혈장 $\beta$-carotene 농도는 대조군 0.21mg/L, 고혈압환자 0.22 mg/L로 나타나 고혈압 유무에 따른 차이가 없었고, 혈장 비타민 A,E 농도 및 총 항산화능력은 대조군에 비해 고혈압환자에게서 유의적으로 높게 나타났다. 또한 혈장 지질과산화물의 농도도 유의적이지는 않지만 고혈압환자에게서 높은 경향이 나타났다. 따라서 고혈압에 따른 항산화 영양상태를 비교한 결과 전반적인 항산화 비타민의 섭취량, 혈중 비타민 농도 및 총 항산화능력이 예상과 달리 대조군 보다 고혈압환자에게서 유의적으로 높게 나타났다. 이런 결과는 질환자들이 자신이 가진 질병의 진전을 막거나 치료의 목적으로 치료제를 복용하고, 식이요법을 실시하고 있기 때문으로 사료되며, 고혈압과 같이 산화적 스트레스가 증가하는 질환의 경우 체내 항산화 체계 반응이 이러한 변화에 효율적으로 대처하기 위한 방향으로 증가되었을 가능성이 있을 것으로 사료된다. 특히, 본 연구의 대상자들의 유병기간이 6.1년으로 비교적 길기 때문에 질환의 진행정도에 따른 항산화 상태를 측정하거나 비교적 질환으로 판정된 직후의 사람들의 대상으로 한 연구 등 더 많은 연구가 필요하다.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.286-293
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• 2019

Hypertension (HTN) is one of the major chronic diseases, and HTN is defined as being in a state of continuous high blood pressure. Left ventricular hypertrophy (LVH) is a condition in which the mass of the left ventricle has increased, and HTN is a leading cause of LVH. HTN and LVH are known to be caused by the interaction of environmental factors and genetic factors. It has been reported that the polymorphisms of SLC8A1, among the genetic factors that affect high blood pressure, are related to salt sensitivity hypertension. In this study, the genetic polymorphisms of SLC8A1 were chosen based on the Korean Genome and Epidemiology data. Logistic regression analysis was then performed for HTN and LVH. Linear regression analysis was also performed for systolic blood pressure (SBP) and diastolic blood pressure (DBP). As a result, 5 SNPs showed statistically significant associations (P<0.05) with HTN, and 10 SNPs showed statistically significant associations with LVH. rs1002671 and rs9789739 showed significant correlation at the same time with HTN and LVH. These results suggest that the polymorphisms of the SLC8A1 gene are linked to the development of HTN and LVH in Koreans. We expect these results to help us understand the pathogenic mechanisms for HTN and LVH.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.5
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• pp.241-252
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• 2019

To choose appropriate countermeasures against potential coastal disaster damages caused by a storm surge, it is necessary to estimate the frequency of storm surge heights estimation. As the coastal populations size in the past was small, the tropical cyclone risk model (TCRM) was used to generate 176,689 synthetic typhoons. In simulation, historical paths and central pressures were incorporated as a probability density function. Moreover, to consider the typhoon characteristics that resurfaced or decayed after landfall on the southeast coast of China, incorporated the shift angle of the historical typhoon as a function of the probability density function and applied it as a damping parameter. Thus, the passing rate of typhoons moving from the southeast coast of China to the south coast has improved. The characteristics of the typhoon were analyzed from the historical typhoon information using correlations between the central pressure, maximum wind speed ($V_{max}$) and the maximum wind speed radius ($R_{max}$); it was then applied to synthetic typhoons. The storm surges were calculated using the ADCIRC model, considering both tidal and synthetic typhoons using automated Perl script. The storm surges caused by the probabilistic synthetic typhoons appear similar to the recorded storm surges, therefore this proposed scheme can be applied to the storm surge simulations. Based on these results, extreme values were calculated using the Generalized Extreme Value (GEV) method, and as a result, the 100-year return period storm surge was found to be satisfactory compared with the calculated empirical simulation value. The method proposed in this study can be applied to estimate the frequency of storm surges in coastal areas.

• Journal of Korea Entertainment Industry Association
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• v.15 no.8
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• pp.351-361
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• 2021

This study was conducted to identify the factors of hypertension treatment in Gwangju and to establish a hypertension cure rate management plan by using local community health surveys to provide the hypertension cure rate management plan centering around the wellness local community. The research collected 13,714 Gwangju research data among a total of 685,820 local community health surveys of KDCA (Korea Disease Control and Prevention Agency) from 2017 to 2019. Among the data, 2,941 subjects, those with diagnosed hypertension aged over 30, were selected and analyzed through SAS 9.4, SAS Enterprise Miner 15.1. The results are as follows. The differences in hypertension diagnosis cure rate in Gwangju based on the subjects' socioeconomic characteristics were shown in gender, age, marital status, level of educational attainment, economic activity status, and monthly income. The significant differences in hypertension cure rate based on health behavior characteristics were shown in current smoking, monthly alcohol consumption, high-risk drinking, breakfast, recognition of good health level, diabetes and treatment, annual unmet medical needs, and annual health center use. As a result of the logistic regression analysis and interactive decision tree analysis to identify the factors affecting hypertension treatment, the research found that the factors that appear are age, marital status, diabetes and treatment, and annual unmet medical needs. Accordingly, to increase the recognition of the importance of hypertension treatment to people of young ages and not to develop complications, public health-educational effort in Gwangju is needed with an effective preparation plan.

• 한국노년학
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• v.29 no.1
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• pp.135-147
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• 2009

Recently, The number of hypertension is increasing with westernized diet and lack of exercise. Many researchers are trying to treat and prevent hypertension by exercise therapy. However, not only did most of studies analyze the effect and usefulness of exercise related to lowering hypertension, but also there is no analysis of the difference of fitness with regard to hypertension according to ages. It is assumed to be important research work to be continued to identify, from the public health's point of view, the difference of fitness with regard to hypertension according to ages can be a essential data for treating and preventing hypertension. Thus, this study is to identify the difference of fitness according to hypertension of adult female over 20s and emphasize the importance of fitness level to the hypertension. Also, this study is to devise valuable study by examining the difference of cardiovascular function. Subjects were 8889 of adult female over 20s. Subjects visited promotion of health center at Y Gu public health center and took comprehensive medical test including hypertension test in Seoul in Korea. It was divided into normal, prehypertension, stage I hypertension and stage II hypertension group by JNC7. The evaluation of cardiorespiratory function was by resting heart rate and lung capacity, the evaluation of fitness was by cardiorespiratory endurance, muscular endurance, muscular strength, power, agility, balance, and flexibility, and the difference of fitness was analyzed by ANCOVA revising independent variable of BMI, drinking, and smoking which affects hypertension. At result, there was significant difference between normal and hypertension group according to most ages in two variable of all cardiorespiratory function, seven fitness variable. Through this study, it was defined that hypertension group had lower cardiorespiratory function and fitness than normal group.