• Title/Summary/Keyword: multi-scale methods

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Diagnostic Accuracy of Percutaneous Transthoracic Needle Lung Biopsies: A Multicenter Study

  • Kyung Hee Lee;Kun Young Lim;Young Joo Suh;Jin Hur;Dae Hee Han;Mi-Jin Kang;Ji Yung Choo;Cherry Kim;Jung Im Kim;Soon Ho Yoon;Woojoo Lee;Chang Min Park
    • Korean Journal of Radiology
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    • v.20 no.8
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    • pp.1300-1310
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    • 2019
  • Objective: To measure the diagnostic accuracy of percutaneous transthoracic needle lung biopsies (PTNBs) on the basis of the intention-to-diagnose principle and identify risk factors for diagnostic failure of PTNBs in a multi-institutional setting. Materials and Methods: A total of 9384 initial PTNBs performed in 9239 patients (mean patient age, 65 years [range, 20-99 years]) from January 2010 to December 2014 were included. The accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of PTNBs for diagnosis of malignancy were measured. The proportion of diagnostic failures was measured, and their risk factors were identified. Results: The overall accuracy, sensitivity, specificity, PPV, and NPV were 91.1% (95% confidence interval [CI], 90.6-91.7%), 92.5% (95% CI, 91.9-93.1%), 86.5% (95% CI, 85.0-87.9%), 99.2% (95% CI, 99.0-99.4%), and 84.3% (95% CI, 82.7-85.8%), respectively. The proportion of diagnostic failures was 8.9% (831 of 9384; 95% CI, 8.3-9.4%). The independent risk factors for diagnostic failures were lesions ≤ 1 cm in size (adjusted odds ratio [AOR], 1.86; 95% CI, 1.23-2.81), lesion size 1.1-2 cm (1.75; 1.45-2.11), subsolid lesions (1.81; 1.32-2.49), use of fine needle aspiration only (2.43; 1.80-3.28), final diagnosis of benign lesions (2.18; 1.84-2.58), and final diagnosis of lymphomas (10.66; 6.21-18.30). Use of cone-beam CT (AOR, 0.31; 95% CI, 0.13-0.75) and conventional CT-guidance (0.55; 0.32-0.94) reduced diagnostic failures. Conclusion: The accuracy of PTNB for diagnosis of malignancy was fairly high in our large-scale multi-institutional cohort. The identified risk factors for diagnostic failure may help reduce diagnostic failure and interpret the biopsy results.

Lateral Resistance Behavior Analysis of Drilled Shafts in Multi-layered Soil (다층지반에 근입된 현장타설말뚝의 수평 지지거동분석)

  • Jang, Seo-Yong;Jeong, Jae-Hoon;Kim, Jong-Ryeol
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.12 no.4
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    • pp.61-70
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    • 2008
  • In this research, load-transfer-function method was selected, because that is widely used in geotechnical engineering among the analysis methods to verify the behavior of load-lateral displacement. Lateral loading test of field scale was conducted, this measured data was analyzed. From the analysis, the model of load-lateral displacement was suggested. The test results were studied and compared to the commercial programs, 'LPILE', which contain the load transfer functions proposed before. By analysis of measure data of load-lateral displacement that expressed to several functions, $y=ae^{bx}$ model was the simplest and applicable to the field. In that case a value converged about 1.3, b value had a tendency to converge about 0.02. From the comparison analysis between measured data and load transfer function by 'LPILE', it is examined that if the lateral load is small, calculated displacements of them show a similar value compared to measured values. Furthermore, the bigger lateral loads, the bigger calculated values compared to the measured data. If the results are compared by Matlock-Reese method and Matlock-API method, Matlock-Reese method shows result of safe side because lateral displacement is calculated greatly relatively.

A Study on Teaching-Learning and Evaluation Methods of Environmental Studies in the Middle School (중학교 "환경" 교과의 교수.학습 및 평가 방법 연구)

  • 남상준
    • Hwankyungkyoyuk
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    • v.7 no.1
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    • pp.1-17
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    • 1994
  • This study was performed to determine appropriate teaching-learning and evaluation methods for Environmental Studies. To promote the relevance of our study to the needs of the schools and concerned educational communities of environmental education, we reviewed related literature, conducted questionnaire surveys, interviewed related teachers and administrator, held meetings with experts, and field-tested our findings. For selecting and developing teaching-learning methods of Environmental Studies, findings of educational research in general are considered. moreover, principles of environmental education, general aim of environmental education, orientations of environmental education, and developmental stages of middle school students in educational psychology were attended. In addition, relevance to the purpose of the Environmental Studies curriculum, appropriateness for value inquiry as well as knowledge inquiry, small group centered class organization, social interaction centered teaching-learning process, regional environmental situation, significance of personal environment, evaluation methods of Environmental Studies, multi- and inter-disciplinary contents of the Environmental Studies textbook, suitability to the evaluation methods of Environmental Studies, and emphasis on the social interaction in teaching-learning process were regarded. It was learned the Environmental Studies can be taught most effectively in via of holding discussion sessions, conducting actual investigation, doing experiment-practice, doing games and plate, role-playing and carrying out simulation activities, and doing inquiry. These teaching-learning methods were field-tested and proved appropriate methods for the subject. For selecting and developing evaluation method of Environmental Studies, such principles and characteristics of Environmental Studies as objective domains stated in the Environmental Studies curriculum, diversity of teaching-learning organization, were appreciated. We categorized nine evaluation methods: the teacher may conduct questionnaire surveys, testings, interviews, non-participatory observations; they may evaluate student's experiment-practice performances, reports preparation ability, ability to establish a research project, the teacher may ask the students to conduct a self-evaluation, or reciprocal evaluation. To maximize the effect of these methods, we further developed an application system. It considered three variables, that is, evaluates, evaluation objectives domains, and evaluation agent, and showed how to choose the most appropriate methods and, when necessary, how to combine uses of different methods depending on these variables. A sample evaluation instrument made on the basis of this application system was developed and tested in the classes. The system proved effective. Pilot applications of the teaching-learning methods and evaluation method were made simultaneously; and the results and their implications are as follows. Discussion program was applied in a lesson dealing with the problems of waste disposal, in which students showed active participation and creative thinking. The evaluation method used in this lesson was a multiple-choice written test for knowledge and skills. It was shown that this evaluation method and device are effective in helping students' revision of the lesson and in stimulating their creative interpretations and responces. Pupils showed great interests in the actual investigation program, and this programme was proved to be effective in enhancing students' participation. However, it was also turned out that there must be pre-arranged plans for the objects, contents and procedures of survey if this program is to effective. In this lesson, non-participatory observation methods were used with a focus on the attitudes of students. A scaled reported in general description rather than in grade. Experiment-practice programme was adopted in a lesson for purifying contaminated water and in this lesson, instruction objectives were properly established, the teaching-learning process was clearly specified and students were highly motivated. On the other hand, however, it was difficult to control the class when some groups of students require more times to complete their experiment, and sometimes different results. As regards to evaluation, performance observation test were used for assessing skills and attitudes. If teachers use well-prepared Likert scale, evaluation of all groups within a reasonablely short period of time will be possible. The most effective and successful programme in therms of students' participation and enjoyment, was the 'ah-nah-bah-dah-market' program, which is kind of game of the flea market. For better organized program of this kind, however, are essential, In this program, students appraise their own attitudes and behavior by responding to a written questionnaire. In addition, students were asked to record any anecdotes relating to self-appraisal of changes on one's own attitudes and behaviours. Even after the lesson, students keep recording those changes on letters to herself. Role-playing and simulation game programme was applied to a case of 'NIMBY', in which students should decide where to located a refuse dumping ground. For this kind of programme to e successful, concepts and words used in the script should be appropriate for students' intellectual levels, and students should by adequately introduced into the objective and the procedures of the lessons. Written questionnaire was used to assess individual students' attitudes after the lesson, but in order to acquire information on the changes of students' attitudes and skills, pre-test may have to be made. Doing inquiry programme, in which advantages in which students actually investigated the environmental influence of the areas where school os located, had advantages in developing students' ability to study the environmental problems and to present the results of their studies. For this programme to be more efficient, areas of investigation should be clearly divided and alloted to each group so that repetition or overlap in areas of study and presentation be avoided, and complementary wok between groups bee enhanced. In this programme, teacher assessed students' knowledge and attitudes on the basis of reports prepared by each group. However, there were found some difficults in assessing students' attitudes and behaviours solely on the grounds of written report. Perhaps, using a scaled checklist assessing students' attitudes while their presentation could help to relieve the difficulties.

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A Study on the Relationship between Job Stress and Socio-Psychological stress of firefighter (소방공무원의 직무스트레스와 사회심리적 스트레스와의 연관성에 관한 연구)

  • Kang, Byung-Woo
    • The Korean Journal of Emergency Medical Services
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    • v.13 no.1
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    • pp.35-48
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    • 2009
  • Purpose: Firefighters were subjected to be exposed to 24-hour shiftwork and high level of job stress, but there is little study of fire fighters about between Job Stress and Psychological stress in Korea. This study was performed to evaluate job stress of fire fighters grouped by different job types and analyze the health effect of job stress by using a PWI-SF(Psycho-social Well-being Index, Short Form). Methods : This study was to measure the degree of job stress and socio-psychological stress of firefighters working at 119 safety center and analyze the relationship between job stress and mental health, through self-administered questionnaire survey on 918 fire fighters working at fire department located in Korea, during October in 2008. Question items of the questionnaire consist of general characteristics, job stress, and socio-psychological stress. Job Stress Measurement Scale for Koreans was used to measure job stress, while PWI-SF used for socio-psychological stress. Collected data was analyzed through frequency analysis, ${\chi}^2$ test, one-way ANOVA, correlation analysis, multi-regression analysis using a statistic program, SPSS/10.0 Ver for Windows, and statistical significance level was 0.05. Result : Accordingly, this paper is written for the purpose of scrutinizing the reason of 119 rescuers' job stress and Socio-Psychological stress. This thesis tries to analyze a problem and provide contents through many variables concerned and theoretical investigation with the actual research of questionnaire. The results of the study are summarized as follows : Fire fighters feel relatively high stressful in their performance. Job stress, organizational commitment and burnout did not have been influence upon by individual cases such as economic condition, regular exercise etc. Finally, as a result of step by step regression analysis, the variable that can explain Socio-Psychological stress the best was negative emotion scale(NE). Conclusions : It is necessary to conduct repeated studies in the future, since the study implied that there was a contrary relationship between job stress and socio-psychological stress. In order to reduce job stress and maintain better mental health, it is more important than anything else to help firefighters have willingness and efforts to sustain a healthy life, so the development of various programs and education to raise their awareness should be implemented.

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Study of Improvement of Search Range Compression Method of VP-tree for Video Indexes (영상 색인용 VP-tree의 검색 범위 압축법의 개선에 관한 연구)

  • Park, Gil-Yang;Lee, Samuel Sang-Kon;Hwang, Jea-Jeong
    • Journal of Korea Multimedia Society
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    • v.15 no.2
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    • pp.215-225
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    • 2012
  • In multimedia database, a multidimensional space-based indexing has been used to increase search efficiency. However, this method is inefficient in terms of ubiquity because it uses Euclidean distance as a scale of distance calculation. On the contrary, a metric space-based indexing method, in which metric axiom is prerequisite is widely available because a metric scale other than Euclidean distance could be used. This paper is attempted to propose a way of improving VP-tree, one of the metric space indexing methods. The VP-tree calculates the distance with an object which is ultimately linked to the a leaf node depending on the node fit for the search range from a root node and examines if it is appropriate with the search range. Because search speed decreases as the number of distance calculations at the leaf node increases, however, this paper has proposed a method which uses the latest interface on query object as the base point of trigonometric inequality for improvement after focusing on the trigonometric inequality-based range compression method in a leaf node. This improvement method would be able to narrow the search range and reduce the number of distance calculations. According to a system performance test using 10,000 video data, the new method reduced search time for similar videos by 5-12%, compared to a conventional method.

A Study on Object-Based Image Analysis Methods for Land Cover Classification in Agricultural Areas (농촌지역 토지피복분류를 위한 객체기반 영상분석기법 연구)

  • Kim, Hyun-Ok;Yeom, Jong-Min
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.4
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    • pp.26-41
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    • 2012
  • It is necessary to manage, forecast and prepare agricultural production based on accurate and up-to-date information in order to cope with the climate change and its impacts such as global warming, floods and droughts. This study examined the applicability as well as challenges of the object-based image analysis method for developing a land cover image classification algorithm, which can support the fast thematic mapping of wide agricultural areas on a regional scale. In order to test the applicability of RapidEye's multi-temporal spectral information for differentiating agricultural land cover types, the integration of other GIS data was minimized. Under this circumstance, the land cover classification accuracy at the study area of Kimje ($1300km^2$) was 80.3%. The geometric resolution of RapidEye, 6.5m showed the possibility to derive the spatial features of agricultural land use generally cultivated on a small scale in Korea. The object-based image analysis method can realize the expert knowledge in various ways during the classification process, so that the application of spectral image information can be optimized. An additional advantage is that the already developed classification algorithm can be stored, edited with variables in detail with regard to analytical purpose, and may be applied to other images as well as other regions. However, the segmentation process, which is fundamental for the object-based image classification, often cannot be explained quantitatively. Therefore, it is necessary to draw the best results based on expert's empirical and scientific knowledge.

Efficacy and Safety of Micro Current Tape on Chronic Low Back Pain: One Group Pre-Post Test Design, Multi Center Pilot Study (만성 요통 통증 완화에 대한 미세전류 테이프의 안전성 및 유효성 평가)

  • Park, Hyun-Gun;Kim, Jong-Yeon;Yi, Woon-Sup;Lee, Sin-Ji;Chung, Won-Suk;Kim, Ho-Jun;Lee, Jong-Soo
    • Journal of Korean Medicine Rehabilitation
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    • v.23 no.4
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    • pp.185-194
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    • 2013
  • Objectives The aim of this study was to evaluate the efficacy and safety of micro current taping therapy (MTT) on patients with chronic low back pain (CLBP). Methods We included 50 participants who met the inclusion criteria and 5 participants dropped out during the sessions due to the following reasons: 3 participants were personal reasons, 1 participant was taking medication, 1 participant was fore arm fracture. We attached "I" shaped 40 cm, 2 tapes along the erector muscles of the spine starting from both iliac crest and another "I" shaped 30 cm, 1 tape on the painful site horizontally. This procedure was done 8 times and participants visited a total of 9 times including a final visit for evaluation. We measured visual analog scale (VAS), range of motion (ROM) and schober's test on every visit. Participants completed a questionnaire of oswestry disability index (ODI) and Beck's depression inventory (BDI) on the first and last visits. Results In VAS for pain intensity and bothersomeness, there were significant decreases after 1st, 6th treatments. In range of extension, there was significant increase after 3rd treatment at first. In range of flexion, there was significant increase after 2nd treatment at first. In range of left flexion, there was significant increase after 4th treatment at first. In range of right flexion, there was significant increase after 3rd treatment at first. in schober's test, there was significant increase after 2nd treatment at first. In VAS, ROM, schober's test, BDI, ODI, there were significant improvement after all treatments had done. Conclusions There was a significant effect of MTT on CLBP. And there was no adverse effect.

Effect of values on major satisfaction in dental hygiene students (치위생(학)과 학생의 가치관이 전공만족도에 미치는 영향)

  • Kim, Mi-Na;Heo, Yun-Min;Kim, Hyoung-Joo;Ahn, Yong-Soon
    • Journal of Korean society of Dental Hygiene
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    • v.15 no.1
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    • pp.81-89
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    • 2015
  • Objectives: The purpose of the study is to investigate the effect of values on major satisfaction in dental hygiene students. Methods: The subjects were 214 dental hygiene students in Seoul and Gyeonggi-do who filled out the self-reported questionnaire after receiving informed consents from January 20 to February 15, 2014. Except incomplete answers, 187 data were analyzed using PASW Statistics 18.0 for Scheffe post hoc test, Pearson correlation coefficient, hierarchical regression analysis, independent sample t-test, and one-way ANOVA. The questionnaire consisted of general characteristics of the subjects and values. General characteristics consisted of gender, age, grade, school record, major choice motivation, and the influencing person to choose the major. The instrument for values was modified from Shin based on MILOV(Multi-Item Measures Of Values) and two professors of dental hygiene verified the validity of the instrument. Instrument for values consisted of 7 questions of values for self-respect, 6 questions of relation oriented values, 5 questions of emotion oriented values, and 5 questions of values for others measured by Likert 5 scale. Cronbach's alpha was 0.769 in the study. The instrument for major satisfaction was modified from Na based on Program Evaluation Survey of Illinois University and two professors of dental hygiene verified the validity of the instrument. Major satisfaction consisted of 7 questions of general satisfaction, 5 questions of consciousness satisfaction, 5 questions of curriculum satisfaction and 3 questions of relation satisfaction measured by Likert 5 scale and Cronbach's alpha was 0.887 in the study. Results: Values of self-respect, relationship orientation and grade had significant influence on general satisfaction, while values of self-respect, relationship orientation and gender had significant influence on consciousness satisfaction. Values of relationship orientation, grade and school record had significant influence on curriculum satisfaction. Grade showed significant influence on relationship satisfaction. Conclusions: Values of self-respect and relationship orientation are the most important factors in dental hygiene students. The guidance for professional career and major satisfaction can be accomplished through the values of self-respect and relationship orientation.

A Study on Design of Wind Blade with Rated Capacity of 50kW (50kW 풍력블레이드 설계에 관한 연구)

  • Kim, Sang-Man;Moon, Chae-Joo;Jung, Gweon-Sung
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.3
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    • pp.485-492
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    • 2021
  • The wind turbines with a rated capacity of 50kW or less are generally considered as small class. Small wind turbines are an attractive alternative for off-grid power system and electric home appliances, both as stand-alone application and in combination with other energy technologies such as energy storage system, photovoltaic, small hydro or diesel engines. The research objective is to develop the 50kW scale wind turbine blades in ways that resemble as closely as possible with the construction and methods of utility scale turbine blade manufacturing. The mold process based on wooden form is employed to create a hollow, multi-piece, lightweight design using carbon fiber and fiberglass with an epoxy based resin. A hand layup prototyping method is developed using high density foam molds that allows short cycle time between design iterations of aerodynamic platforms. A production process of five blades is manufactured and key components of the blade are tested by IEC 61400-23 to verify the appropriateness of the design. Also, wind system with developed blades is tested by IEC 61400-12 to verify the performance characteristics. The results of blade and turbine system test showed the available design conditions for commercial operation.

The Effects of Self-Sit-to-Stand Training Using Multi-Sensory Feedback Device on Balance Ability and Sit-to-Stand Ability in Hemiplegic Stroke Patients (다중감각 되먹임 장치를 이용한 자가 일어서기 훈련이 편마비 환자의 균형능력과 일어서기 동작 수행능력에 미치는 영향)

  • Min, Jun-Ki;Choi, Won-Jae;Jung, Jihye;Lee, Seung-Won
    • PNF and Movement
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    • v.20 no.2
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    • pp.157-166
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    • 2022
  • Purpose: The aim of this research was to investigate the effects of self-sit-to-stand training on balance ability and sit-to-stand ability in hemiplegic stroke patients using a multisensory feedback device. Methods: A total of 19 stroke patients participated in this study, and they were divided into two groups: 10 underwent self-sit-to-stand training using a multisensory feedback device, and 9 underwent sit-to-stand training with a physical therapist. In both groups, sit-to-stand training was performed for 30 min, 3 times a week, for 6 weeks. The subjects also underwent physical therapy twice a day for 30 min, 10 times a week, for a total of 60 sessions. Balance ability was evaluated using the AFA-50 and Berg Balance Scale. Sit-to-stand ability was evaluated using the five times sit-to-stand test. Results: Sway length, pressure, and total pressure all significantly increased in both groups, and there was no difference between the two groups. The Berg Balance Scale results showed that balance ability significantly increased in both groups, and there was no difference between the two groups. The five times sit-to-stand test results showed that sit-to-stand ability significantly increased in both groups, and there was no difference between the two groups. It was found that the self-sit-to-stand training using a multisensory feedback device had a positive effect on balance control and sit-to-stand ability. When the two groups were compared, no difference in balance ability or sit-to-stand ability was observed. Conclusion: The findings of this study indicate that self-sit-to-stand training using a multisensory feedback device is as effective as sit-to-stand training with a physical therapist. Hence, self-sit-to-stand training using a multisensory feedback device could be an effective home-based exercise protocol for hemiplegic stroke patients to improve their balance and sit-to-stand abilities.