• Title/Summary/Keyword: Level set methods

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A study on the relationship of self-efficacy to stressors and stress adaptation in dental hygiene students (치위생과 학생의 자기효능감 수준에 따른 스트레스 요인의 적응방법에 관한 연구)

  • Lim, Mi-Hee;Ku, In-Young;Choi, Hye-Sook
    • Journal of Korean society of Dental Hygiene
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    • v.11 no.5
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    • pp.811-822
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    • 2011
  • Objectives : The purpose of this study was to examine the relationship of the self-efficacy of dental hygiene students to their stressors and ways of stress-adaptation patterns. Methods : The subjects in this study were dental hygiene juniors in four selected colleges located in the metropolitan area. Results : 1. They got a mean of 3.22 in self-efficacy. They gave the highest mark(3.50) to an item 'I can attain it if I set a primary goal.' 2. They got a mean of 3.18 in stressors. Among the stressors, task assignments(3.74) were identified as the greatest stressor, followed by the curriculum(3.25), learning environments(3.16), prospects of employment (3.07) and test anxiety(2.95). 3. They got a mean of 2.02 in stress-adaptation method. They got 2.31 and 1.72 in long-term and short-term adaptation respectively, which showed that long-term stress adaptation method were more prevailing than short-term ones. 4. As a result of analyzing whether there would be any gaps in self-efficacy according to general characteristics, statistically significant gaps were found in that regard according to experience of preparing for college admission after leaving high school, academic standing, satisfaction with the department of dental hygiene and prospects of employment(p<.05). 5. As a result of checking the relationship of their self-efficacy to their stressors and ways of stress adaptation method, there were statistically significant differences in that aspect according to examinations and prospect of employment(p<0.05). As for ways of stress adaptation method, there were statistically significant differences in long-term adaptation method (p<0.05). Conclusions : As it's found that the level of the self-efficacy of the dental hygiene students was linked to the efficiency of their ways of stress adaptation method, the development and implementation of programs geared toward boosting the self-efficacy of dental hygiene students are required to teach them to successfully cope with various kinds of stress that they are likely to face after getting a job.

The Effects of Needle Electrode Electrical Stimulation on Cellular Necrosis Blocking the Hippocampus after Induction of Ischemia (침전극저주파 자극이 해마의 세포사 차단에 미치는 영향)

  • Lee, Jung-Sook;Kim, Byung-Ki;Kim, Sung-Won;Kim, Ji-Sung;Kim, Dong-Il;Song, Chi-Won
    • Journal of Oriental Neuropsychiatry
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    • v.20 no.2
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    • pp.111-120
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    • 2009
  • Objectives : This study was performed to investigate the effects of Needle Electrode Electrical Stimulation (NEES) on ischemia-induced cerebrovascular accidents. After obstruction and reperfusion of ${\ast}{\ast}$ arteries in white mice, the amounts of necrosis and inflammation related substances IL-6, Caspase-3, and PARP, C-fos were measured in neurons of the hippocampus. The following results were obtained. Methods : This study used 21 male specific pathogen free (SPF) SD (Sprague Dawley) rats, 8 weeks of age and approximately 300 g in weight, that were given at least 1 week to adapt to the lab environment Each exposed artery was completely occluded with non-absorbent suture thread and kept in that state for 5 minutes. The sutures were then removed to allow reperfusion of blood. Test group is control group for comparison with the common carotid artery occlusion models, a GI group that underwent common carotid artery occlusion, and a needle electrode electrical stimulation (NEES) group that underwent NEES after artery occlusion. The GI and NEES groups were given 12, 24, or 48 hours of reperfusion before NEES. NEES device (PG6, ITO, Japan, 9V, current, 2Hz) was used to stimulate the right and left acupoint ST36 of the SD rats for 30 minutes while they were sedated with 3% isoflurane. An immunohistochemistry test was done on the forebrains of the GI induced rats. All the data collected from this study was symbolized and analyzed using a statistics processing program (SPSS 12.0K/PC). The level of significance was set at ${\alpha}$=0.05 and a T-TEST analysis was used to find out the effects of treatment on each of the groups: the normal group, the CVA induced group, and the treatment after CVA induction group. Results : Both PARP and C-fos immuno-reactive cells, related to apoptosis, were greater in the GI groups than the NEES group. Caspase and IL-6 immuno-reactive cells, related to inflammation, were greater in the GI and NEES groups than the control group. Conclusions : This research was conducted to study the effects of NEES on CVA due to ischemia. Occlusion and reperfusion was performed on the common carotid arteries of white rats, after which amounts of substances related to neuron necrosis and inflammation - PARP, IL-6, Caspase-3, and C-fos - were measured in the Hippocampus

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Analysis of Allowable Stresses of Machine Graded Lumber in Korea (국내 기계등급구조재의 허용응력 분석)

  • Hong, Jung-Pyo;Oh, Jung-Kwon;Park, Joo-Saeng;Han, Yeon Jung;Pang, Sung-Jun;Kim, Chul-Ki;Lee, Jun-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.4
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    • pp.456-462
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    • 2015
  • 365 pieces of domestic $38{\times}140{\times}3600mm$ Red pine structural lumber were machine graded conforming to a softwood structural lumber standard (KS F 3020). The allowable bending stresses calculated for each grade were compared with the values currently tabulated in the standard. Four calculation methods for lower $5^{th}$ percentile bending stress were non-parametric estimation with 75% confidence level, 2-parameter and 3-parameter Weibull distribution fit, and bending modulus of rupture (MOR)-modulus of elasticity (MOE) regression based method. Only the data set of Grades E8, E9, and E10 were statistically eligible for the $5^{th}$ percentile calculation. The MOR-MOE regression based method only was able to estimate the lower $5^{th}$ percentile values theoretically for the full range of grades. The results showed that all allowable bending stresses calculated were lower than the design values tabulated in the standard. This implies that the current machine grading system has the pitfall of structural safety. Improvement in current machine grading system could be achieved by introducing the bending strength and stiffness combination grade system.

Optimization Technique for Estimation of Potential Hydroelectric Energy at Existion Ahricultural Reservoir (최적화기법을 이용한 기존 농업용 저수지에서의 부존 수력발전량 추정)

  • An, Tae-Jin;Ryu, Hui-Jeong;Park, Jeong-Eung
    • Journal of Korea Water Resources Association
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    • v.32 no.3
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    • pp.281-289
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    • 1999
  • Small-scale hydropower projects at existing agricultural reservoirs can contribute to produce electric energy by maximizing the use of releases from the reservoirs. The irrigation water duration, the reservoir hydropower simulation, and the nonlinear programming model are employed to estimate potential hydroelectric energy at an existing reservoir. The nonlinear programming model consists of finding a maximum hydroelectric energy subject to irrigation water demand constraints. The sample reservoir given a set of inflow and irrigation water is considered. The optimal solutions by the optimization model yield the most hydroelectric energy for the analysis period in the three methods. Consequently, the nonlinear programming model uses the most water for hydropower generation with respect to the total inflow of the sample reservoir. It is also found that additional storage by increasing the normal water level of the sample reservoir does not significantly increase the annual hydroelectric energy for the given reservoir. It is expected that the optimization model and the proposed procedure for estimating potential hydroelectric energy can be applied to evaluate feasibility analysis for small scale hydropower additions at existing agricultural dams.

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Changes in the Growth Characteristics and the Content of Decursin and Decursinol angelate in Angelica gigas Nakai by Mineral and Hormonal Agent Treatment (미네랄 및 호르몬 제제 처리에 따른 당귀의 생육특성 및 Decursin, Decursinol Angelate 함량 변화)

  • Lee, Sang Hoon;Yun, Hyeong Muk;Koo, Sung Cheol;Lee, Woo Moon;Chang, Jae Ki;Koo, Hyun Jeong;Chang, Kwang Jin;Kim, Yeon Bok
    • Korean Journal of Medicinal Crop Science
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    • v.26 no.3
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    • pp.227-232
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    • 2018
  • Background: Angelica gigas Nakai is a perennial herb belonging to the family Umbelliferae. Its roots are utilized in traditional medicine. The aim of this study was to increase the yield of and the content of two indicator components (decursin and decursinol angelate) in A. gigas Nakai. Methods and Results: The roots of A. gigas Nakai were harvested 4-times from late August to late October in 2017. Two agents (trace element-TE, and plant hormone-HM) were applied 4 times at intervals of 2 weeks. The content of the two indicator components were analyzed by high performance liquid chromatography. The HM treatment showed the greatest increase in underground part yield and root diameter. The content of the two indicator components in the control (non-treatment) group was the highest in the underground part, but was higher in the aerial parts in the agent treatment group. After treatment with the agents, the content of the indicator components tended to decrease in the underground part. However, the total content of the indicator components in the two agent treatment groups exceeded the level of 6% set by the Korean Pharmacopoeia. Conclusions: The highest underground part yield was found in the HM treatment group, while the highest content of decursin and decursinol angelate were found in the control group. This study provides basic information for yield improvement in A. gigas.

Performance Evaluation of Balance Ability Equipment Using VR (VR을 이용한 균형능력 측정장비의 성능평가)

  • Yoon, Sangcheol;An, Howon;Ahn, Taekwon;Choi, Haesung;Lee, Byoungkwon;Seo, Dongkwon;Lee, Kyuhwan;Jung, Sangwoo;Yi, Jaehoon
    • Journal of The Korean Society of Integrative Medicine
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    • v.8 no.3
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    • pp.33-41
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    • 2020
  • Purpose : Conventional Balance Measurement can only measure the center of gravity and the shaking movement of the body. As a result, it has the disadvantages of not responding to visual changes and blocking functions of variables. This study was carried out to evaluate the performance of new equipment that measures the balance of the body using changes in body segment and pressure using the acceleration sensor to compensate for the disadvantages of the existing equipment. Methods : To this end, balance ability was measured in 43 healthy male/female adults without orthopedic injuries and nervous system damage in the last 6 months. in a situation where the visual information was restricted by Virtual Reality (VR) gear, all subjects measured and evaluated the balance ability utilizing the new equipment. Balance measurement (Prime Medilab, Korea) and Wii fit (Nintendo, Japan) were used to measure the balance ability of the subjects, and the balance ability test was performed in 4 postures using each device for data acquisition. The test duration for each posture was 30 seconds. For data acquisition, the average value of three experiments measured using each equipment was analyzed, and the statistical test was performed using the independent sample and the corresponding sample t-test, and the significance level was set to α=.05. Results : As a result of measuring the balance ability using individual equipment, blocking visual information using VR gear, the average speed, maximum speed, and moving area of the COP increased equally. It was found that the obtained absolute size of the result in Wii was somewhat larger than that of BM. Conclusion : It is considered that in the future research, it is necessary to measure changes in the body's center of gravity through image analysis, etc., to make clear comparison and evaluation of the usability.

Effects of an Intensive Management Program for Diabetic Patients on a Blood Biochemical Profile and Diabetes Knowledge (당뇨병 환자 대상 집중관리프로그램이 혈액성상 및 당뇨지식에 미치는 효과)

  • Yeo, Su-Jeong;Kim, Bok-Hee
    • Korean Journal of Community Nutrition
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    • v.23 no.2
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    • pp.148-161
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    • 2018
  • Objectives: This study examined the effects of nutrition education and exercise therapies on the hematological status and diabetes knowledge of diabetic patients. For this purpose, a 12-week intensive management program was provided to diabetic patients participating in an exercise program in S health subcenter in Kwangju city and the effects were analyzed. Methods: The subjects were 26 diabetic patients, who provided written informed consent. As a preliminary survey, this study examined the general characteristics, physical status, obesity, blood pressure, hematological status, daily activity level, diabetes knowledge, diet performance, and barriers to diet therapy. After the 12-week intensive management program was completed, a post-test was conducted in the same way as the preliminary test. The data were analyzed with using SPSS 18.0. The data from this study are presented as the mean${\pm}$standard deviation. A paired t-test was conducted to compare differences in the means before and after the program. Statistical significance was set to p<0.05. Results: The results of the program are presented as follows. The HDL-cholesterol levels changed from $39.8{\pm}10.5mg/dL$ to $48.3{\pm}13.1mg/dL$, showing a significant increase (p<0.001). The blood sugar 2 hours after a meal changed from $175.2{\pm}67.1mg/dL$ to $140.5{\pm}42.5mg/dL$, showing a significant decrease (p=0.014). The glycosylated hemoglobin levels decreased significantly from $6.7{\pm}1.1%$ to $6.3{\pm}1.0%$ (p=0.010). The total scores of the daily activity levels increased significantly from $3.8{\pm}2.4$ to $4.8{\pm}2.5$ (p=0.040). The scores of knowledge on diabetes increased from $11.5{\pm}3.6$ to $14.0{\pm}3.8$ (p=0.001). The scores of knowledge on diet therapy changed from $6.7{\pm}2.2$ to $7.9{\pm}1.7$, showing a significant increase (p=0.027). Conclusions: The 12-week intensive management program intervened by nutrition education and exercise therapies induced positive changes to the HDL-cholesterol, blood sugar 2 hours after a meal, glycosylated hemoglobin, daily activity levels, and knowledge on diabetes.

An Interdisciplinary Approach for the Solution of Enviromental polution (環境汚染의 解決을 위한 綜合科學的 接近方法 (I))

  • Sin, Hyeon-Deok
    • Journal of the Korean institute of surface engineering
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    • v.12 no.3
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    • pp.207-216
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    • 1979
  • Environmental pollution or contaminations caused by various kinds of pollutants have become one of most serious problems of our time. Environ mental pollution is the unfavoralble alteration of our surroundings, through direct or indirect effects of changes in energy patterns, rediation levels, chemical and physical constitution and abundances of organisms. These changes may affect humans directly or through their supplies of water and of agicultural and other biological products, their physical objects or possessions, or their opportunities for recreation and appreciation of nature. Pollutants that meet the criteria of this definition of environmental pollution are numerous: gases (such as sulfur dioxide and nitrogen oxides) and paniculate matter (such as smoke particles, lead aerosols, and asbestos) in the atmosphere; pesticides and radioactive isotopes in the atmosphee and in waterways; sewage, organic. chemicals, and phosphates in water; solid wastes on land; excessive heating (thermal pollution) of rivers and lakes; and many others. Some of these pollutants are introduced into the environment naturally, others by human actions, and most in both ways. Our major concer is with environmental pollution resulting wholly or largely as a by-product of human activities, because these can be controlled most readily. Environmental pollution cannot be solved by science and technology alone. It should be handled by an interdisciplinary approach with combined methods of science and technology as wen as social science disciplines for the better solution of this critical problem. In this respect, introducing "Environmental Science," a new scientific approach for the solution of environmental problems, which is now widely accepted by most developed countries of the world will be very helpful for systematization of theoretical basis for a new scientific approach to environmental pollution. Environmental science is "the study of all systems of air, land, water, energy, and life that surround Man. It includes all sciences directed to the system-level of understanding of the environment, drawing especially upon such disciplines as meteorology, geophysics, oceanography, and ecology, and utilizing to the fullest knowledge and techniques developed in such fields as physics, chemistry, biology, mathematics and engineering as well as many social science disciplines, such as economics, such as economics, law, political science and public administration." The components of this discipline are not new, for they are drawn from existing areas of science within biology chemistry, physics, and geoscience. What is really new about environmental science, however, is it siewpoint - its orientation to global problems, its conception of the earth as a set of interlocking, interacting systems, and its interest in Man as a part of these systems.

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Study on image quality improvement using Non-Linear Look-Up Table (비선형 Look-Up Table을 통한 영상 화질 개선에 관한 연구)

  • Kim, Sun-Chil;Lee, Jun-Il
    • Korean Journal of Digital Imaging in Medicine
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    • v.5 no.1
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    • pp.32-44
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    • 2002
  • The role of radiology department has been greatly increased in the past few years as the technology in the medical imaging devices improved and the introduction of PACS (Picture Archiving and Communications System) to the conventional film-based diagnostic structure is a truly remarkable factor to the medical history. In addition, the value of using digital information in medical imaging is highly expected to grow as the technology over the computer and the network improves. However, the current medical practice, using PACS is somewhat limited compared to the film-based conventional one due to a poor image quality. The image quality is the most important and inevitable factor in the PACS environment and it is one of the most necessary steps to more wide practice of digital imaging. The existing image quality control tools are limited in controlling images produced from the medical modalities, because they cannot display the real image changing status. Thus, the image quality is distorted and the ability to diagnosis becomes hindered compared to the one of the film-based practice. In addition, the workflow of the radiologist greatly increases; as every doctor has to perform his or her own image quality control every time they view images produced from the medical modalities. To resolve these kinds of problems and enhance current medical practice under the PACS environment, we have developed a program to display a better image quality by using the ROI optical density of the existing gray level values. When the LUT is used properly, small detailed regions, which cannot be seen by using the existing image quality controls are easily displayed and thus, greatly improves digital medical practice. The purpose of this study is to provide an easier medical practice to physicians, by applying the technology of converting the H-D curves of the analog film screen to the digital imaging technology and to preset image quality control values to each exposed body part, modality and group of physicians for a better and easier medical practice. We have asked to 5 well known professional physicians to compare image quality of the same set of exam by using the two different methods: existing image quality control and the LUT technology. As the result, the LUT technology was enormously favored over the existing image quality control method. All the physicians have pointed out the far more superiority of the LUT over the existing image quality control method and highly praised its ability to display small detailed regions, which cannot be displayed by existing image quality control tools. Two physicians expressed the necessity of presetting the LUT values for each exposed body part. Overall, the LUT technology yielded a great interest among the physicians and highly praised for its ability to overcome currently embedded problems of PACS. We strongly believe that the LUT technology can enhance the current medical practice and open a new beginning in the future medical imaging.

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A Study on Patients Dose and Image Quality according to Source to Image receptor Distance in Abdomen Radiography: comparison of ESD measured and DRLs in other countries (복부일반촬영시 선원과 검출기간의 거리변화에 따른 영상 화질 및 피폭선량에 관한 연구)

  • Jang, Ji-Sung;Choi, Weon-Keun;Jung, Jae-Yon;Lee, Kwan-Sub;Ha, Dong-Yoon
    • Korean Journal of Digital Imaging in Medicine
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    • v.14 no.2
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    • pp.39-46
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    • 2012
  • Purpose : The purpose of this study was to reduce Entrance Surface Dose and maintain image quality by changing Source to Image receptor Distance. And we'd like to compare ESD on this study to DRLs in other contries. Materials and Methods : We used indirect DR system(Definium 8000, General Electric, USA)and phantom(ART-200X, Flukebiomedical, USA),glass dosimeters(GD-352M, Asahi Techno Glass, Japan)for this study. The imagies were obtained throuh 80kVp fixed, and different tube currents using AEC mode in $16{\times}16$(inch) field size and changing Source to Image receptor Distance from 100 cm to 130 cm per 10 cm unit. The phantom with attaching 5 glass dosimeters on abdomonal skin was set at supine and erect position as a anterioposterial projection on detector For measuring Entrance Surface Dose. Image analysis was conducted by histograms of Image J(1.46r) which was given from National Institutes of Health(NIH). Results : Due to inverse square law of distance, the tube currents were increasing 42.6 % in supine position and 32.6 % in erect position according to the change of Source to Image receptor Distance. While Entrance Surface Doses were rapidly decreasing 14.2 % in supine position and 29.4 % in erect position according to the change of Source to Image receptor Distance. As the results of histogram using Image J, pixel mean values from 100 cm to 110 cm, 120 cm and 130 cm were decreasing each 1.4%, 2.5%, 2.7%, 4.5%, 2.2 %, 5.8 % in supine, erect position. While standard deviations from 100 cm to 110 cm, 120 cm and 130 cm were increasing each 1.4 %, 2.5 %, 2.5 %, 4.0 %, 2.0 %, 4.9 % Consequently, there are no significant differences in abdomen images taken. Conclusion: As the results described above, we strongly recommend using long Sourceto Image receptor Distance than 100cm that we have been using. So, we should deliver less Entrance Surface Dose to the patients while maintaining image quality in abdomen radiography.

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