• Title/Summary/Keyword: choice criteria

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Selection of bandwidth for local linear composite quantile regression smoothing (국소 선형 복합 분위수 회귀에서의 평활계수 선택)

  • Jhun, Myoungshic;Kang, Jongkyeong;Bang, Sungwan
    • The Korean Journal of Applied Statistics
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    • v.30 no.5
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    • pp.733-745
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    • 2017
  • Local composite quantile regression is a useful non-parametric regression method widely used for its high efficiency. Data smoothing methods using kernel are typically used in the estimation process with performances that rely largely on the smoothing parameter rather than the kernel. However, $L_2$-norm is generally used as criterion to estimate the performance of the regression function. In addition, many studies have been conducted on the selection of smoothing parameters that minimize mean square error (MSE) or mean integrated square error (MISE). In this paper, we explored the optimality of selecting smoothing parameters that determine the performance of non-parametric regression models using local linear composite quantile regression. As evaluation criteria for the choice of smoothing parameter, we used mean absolute error (MAE) and mean integrated absolute error (MIAE), which have not been researched extensively due to mathematical difficulties. We proved the uniqueness of the optimal smoothing parameter based on MAE and MIAE. Furthermore, we compared the optimal smoothing parameter based on the proposed criteria (MAE and MIAE) with existing criteria (MSE and MISE). In this process, the properties of the proposed method were investigated through simulation studies in various situations.

Comparison of the Characteristics of each Educational Achievement Level of Elementary and Middle School Students Shown in the Chemistry Items of the National Assessment of Educational Achievement (국가수준 학업성취도 평가의 화학 문항에서 나타난 초.중학교 학생의 성취수준별 특징 비교)

  • Choi, Wonho
    • Journal of The Korean Association For Science Education
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    • v.33 no.6
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    • pp.1186-1201
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    • 2013
  • We investigated student's characteristics in each educational achievement level using the results of the NAEA (National Assessment of Educational Achievement) in 2009, 2010, and 2011 for Grade 6 students, and compared the characteristics between elementary and middle school students. The analysis of representative items for each educational achievement level of elementary and middle school students revealed that (a) advanced level students from both elementary and middle school could exactly understand the achievement criteria of the curriculum, (b) proficient level students from both elementary and middle school were understanding the achievement criteria of the curriculum superficially, for example, they could not understand concepts exactly but could memorize terms, and so should have compensational education under situations that ask for short answer or essay type items instead of multiple choice items, and (c) basic level students from both elementary and middle school almost could not understand the achievement criteria of curriculum, and so should have compensational education under situations that only deal with a simple situation. Science concepts treated in science curriculum are hierarchically organized by level of school, and simple compensational education for the students of below basic level will not solve learning deficits in science education. Differentiated education by educational achievement should be largely expanded instead.

MODFLOW or FEFLOW: A Case Study of Groundwater Model Selection for the Upper Waikato Catchment, New Zealand

  • Weir, Julian;Moore, Dr Catherine;Hadfield, John
    • Proceedings of the Korea Water Resources Association Conference
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    • 2011.05a
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    • pp.14-14
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    • 2011
  • Groundwater in the Waikatoregion is a valuable resource for agriculture, water supply, forestry and industries. The 434,000 ha study area comprises the upper Waikato River catchment from the outflow of Lake Taupo (New Zealand's largest lake) through to Lake Karapiro (a man-made hydro lake with high recreational value) (Figure 1). Water quality in the area is naturally high. However, there are indications that this quality is deteriorating as a result of land use intensification and deforestation. Compounding this concern for decision makers is the lag time between land use changes and the realisation of effects on groundwater and surface water quality. It is expected that the effects of land use changes have not yet fully manifested, and additional intensification may take decadesto fully develop, further compounding the deterioration. Consequently, Environment Waikato (EW) have proposed a programme of work to develop a groundwater model to assist managing water quality and appropriate policy development within the catchment. One of the most important and critical decisions of any modelling exercise is the choice of the modelling platform to be used. It must not inhibit future decision making and scenario exploration and needs to allow as accurate representation of reality as feasible. With this in mind, EW requested that two modelling platforms, MODFLOW/MT3DMS and FEFLOW, be assessed for their ability to deliver the long-term modelling objectives for this project. The two platforms were compared alongside various selection criteria including complexity of model set-up and development, computational burden, ease and accuracy of representing surface water-groundwater interactions, precision in predictive scenarios and ease with which the model input and output files could be interrogated. This latter criteria is essential for the thorough assessment of predictive uncertainty with third-party software, such as PEST. This paper will focus on the attributes of each modelling platform and the comparison of the two approaches against the key criteria in the selection process. Primarily due to the ease of handling and developing input files and interrogating output files, MODFLOW/MT3DMS was selected as the preferred platform. Other advantages and disadvantages of the two modelling platforms were somewhat balanced. A preliminary regional groundwater numerical model of the study area was subsequently constructed. The model simulates steady state groundwater and surface water flows using MODFLOW and transient contaminant transport with MT3DMS, focussing on nitrate nitrogen (as a conservative solute). Geological information for this project was provided by GNS Science. Professional peer review was completed by Dr. Vince Bidwell (of Lincoln Environmental).

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A Study on the Improvement and Problems of Marine Officer License Examination System (해기사 면허시험제도의 문제점 및 개선 방안 연구)

  • Kim, Dong-Geun;Kwon, Ki-Soo
    • Journal of Fisheries and Marine Sciences Education
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    • v.13 no.1
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    • pp.99-116
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    • 2001
  • Testing is a procedure used to measure a sample of behaviour in order to discover how well a seafarer performs, usually in comparison with others, or compared with identified performance criteria. In this context It is important that the test, in whatever form it is being used, yields consistent results by being valid, reliable and practical. Whilst we can only take a sample of a person's knowledge or comprehension about topic in this way, testing methods do provide a more reliable estimate of performance than most other observational techniques; unsystematic or irregular observation being too unreliable. The method of examination has been specified in the provisions of Regulation 12 of the Decree of the ship officers act as followings. Other necessary matters for conducting oral and written examinations have been set out by the Minister. But written examination is too shortage of period and small number of question to cover the qualification of each level and oral test is just simple and namely Traditionally, written examinations have been provided as the only means for determining the acquisition of knowledge by the mariner. Typically, the examination formats have taken the format of either an essay or multiple choice examinations. Essay items, used in the vast majority of subject examination(not in Korea), consisted of three basic types: situational, descriptive and computational. The level of certificate being examined determined the number and mix of the type of essay questions selected. Oral question has again been used by assessors of seafarer in a wide variety of contexts. Also, oral questioning is often used when observation of performance is undertaken to ask why a certain action has been taken, or to be broaden the scope of what has been observed. At end, Each techniques have their own advantage and disadvantage, so we have to choose some or all of the following techniques, depending upon the certificate, qualification or job for which the trainee is aiming. But in high lank, we have to use both of essay type and multiple choice and with enough time of oral test at least 30 minutes. Who would be the assessor? According to the STCW Code Section A-I/6, instructors, supervisor and assessors are appropriately qualified for particular types and levels of training or assessment of competence of seafarers either on board or ashore, as required under the Convention, in accordance with the provisions of this section.

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A Study on Location Determining Choice Factor and Satisfaction Evaluation of Companies in Free Economic Zones: Focusing on Incheon and Busan·Jinhae Free Economic Zones (경제자유구역 입주결정 선택기준 및 만족도 평가: 인천, 부산·진해 경제자유구역 중심으로)

  • Kim, Hyun Ah;Kim, Tae Seung
    • Journal of Korea Port Economic Association
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    • v.31 no.4
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    • pp.107-120
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    • 2015
  • This study analyzes Korea's Free Economic Zone (FEZ), by particularly focusing on Incheon and Busan-Jinhae zones, using the Analytic Hierarchy Process (AHP) method and a questionnaire survey analysis. The study compares important selection criteria and satisfaction of resident companies in Incheon and Busan-Jinhae FEZs. The findings are as follows. First, the AHP method results suggest that companies in both Incheon and Busan-Jinhae FEZs are affected by location, economic society, and policy. In subordinate determining factor for land, it is ordered by ease of gaining land, inexpensive rental fee in Incheon and by convenient access to close markets and inexpensive rental fee in Busan-Jinhae. Second, the questionnaire survey results suggest high adjacent market size and easy access in Incheon FEZ and sound logistics infrastructure in Busan-Jinhae FEZ. For this reason, Incheon has a high value of logistics infrastructure and potential market near metropolitan area and Busan-Jinhae, has a high value of transportation Infrastructure near industrial district. These findings will contribute to policy data for activating and promoting the Free Economic Zone.

The Diagnosis and Treatment of Bruxism (이갈이의 진단 및 치료)

  • Jeong-Seung, Kwon;Jung, Da-Woon;Kim, Seong-Taek
    • Journal of Dental Rehabilitation and Applied Science
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    • v.28 no.1
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    • pp.87-101
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    • 2012
  • Bruxism is extensively defined as a diurnal or nocturnal parafunctional habit of tooth clenching or grinding. The etiology of bruxism may be categorized as central factors or peripheral factors and according to previous research results, central factors are assumed to be the main cause. Bruxism may cause tooth attrition, cervical abfraction, masseter hypertrophy, masseter or temporalis muscle pain, temporomandibular joint arthralgia, trismus, tooth or restoration fracture, pulpitis, trauma from occlusion and clenching in particularly may cause linea alba, buccal mucosa or tongue ridging. An oral appliance, electromyogram or polysomnogram is used as a tool for diagnosis and the American Sleep Disorders Association has proposed a clinical criteria. However the exact etiology of bruxism is yet controversial and the selection of treatment should be done with caution. When the rate of bruxism is moderate or greater and is accompanied with clinical symptoms and signs, treatment such as control of dangerous factors, use of an oral appliance, botulinum toxin injection, pharmacologic therapy and biofeedback therapy may be considered. So far, oral appliance treatment is known to be the most rational choice for bruxism treatment. For patients in need of esthetic correction of hypertrophic masseters, as well as bruxism treatment, botulinum toxin injection may be a choice.

The Bibliographical Investigation of Sasang Constitution Diagnosis (사상체질(四象體質) 진단법(診斷法)의 문헌적(文獻的) 고찰(考察) - 외형(外形), 심성(心性), 증(證)을 위주(爲主)로 -)

  • Jung, Won-gyo;Kim, Jong-weon
    • Journal of Sasang Constitutional Medicine
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    • v.11 no.2
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    • pp.95-117
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    • 1999
  • 1. Purpose of study There are many Constitution theories. But, In the Sasang Constitutional medicine, the theory and the practice are connected systematically. So it has been used in Korea popularly. Lee Je-Ma suggested that the external form, the mind, the symptom are the criteria of Sasang constitution diagnosis at the Discourse on the Four Principle and the Discourse on the Identifying Four Constitutions. But The clinical importance study of three diagnostic criteria - the external form, the mind, the symptom - has never been studied. Therefore, there are many obstacles of using the three diagnostic criteria totally. And I think that it needs a study which we apply the three diagnostic criteria to practice and approve the clinical importance of one another. I classify and investigate the previous methods of Sasang constitution diagnosis by the three diagnostic criteria in this study. 2. Method of study I investigate the previous methods of Sasang constitution diagnosis bibliographically by Dongyi Soose Bowon, Journal of Constitutional medicine and other books. 3. Result of study (1) Study of the external form The Study of Ki-sang(氣像) and Sa-ki(詞氣) by experience and intuition was done previously, and study of imaginay formulation of each constitution by measuring Chae-hyung(體形) and yong-mo(容貌) has being done recently. (2) Study of the mind For the objectification of study and diagnosis, self-reporting questionnaire has been used. The ideal choice to determine an indivisual constitution, as far as questionnaire go, is to take results from both the modified version Sasang Pattern Identification Questionnaire and QSCCII. (3) Study of the symptom For the study of the symptom - constitution symptom and constitution symptom of disease - the study of principles, the clinical study of the type of disease and symptom, the study which the pathologic view of Oriental medicine apply the view of Sasang Constitutional medicine have been done. We must try to objectfy Sasang Constitutional disease.

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A Baseline Study on the Choice of Optimal Screening Test Items among Workers with Abnormal Liver Function Tests on Workers' Periodic Health Examination (근로자 건강진단시 간기능 이상자의 정밀검사항목 개선을 위한 조사연구)

  • Cheong, Hae-Kwan;Lim, Hyun-Sul;Kim, Gyu-Hoi
    • Journal of Preventive Medicine and Public Health
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    • v.27 no.4 s.48
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    • pp.747-761
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    • 1994
  • Workers' periodic health examination is the main tools used to manage the health problems of most workers in Korea. The most common health problem found in workers' periodic health examination is liver disorder. Liver disorder is also one of the most common health problems in general population and one of the leading causes of mortality in adult population. Regulation proposed by government (No. 207, Ministry of Labor, 1992) defines the criteria for selection of workers with the liver dysfunction for further evaluative examination and the examination items used for diagnosis of the workers with liver dysfunction. This study was designed to evaluate the proficiency of each examination items presently defined in Regulation and propose the optimal examination items for detection of the liver disorders found by workers' periodic health examination. Study subjects are 186 workers with abnormal liver function tests in screening examination of workers' periodic health examination. Questionnaire survey including past history of liver disorder, drinking history, height and weight was done. Physical examination by physician, routine test items defined by Regulation (SGOT, SGPT, $\gamma$-GTP, protein, albumin, total and direct bilirubin, alkaline phosphatase, $\alpha$-feto protein, HBsAg and anti-HBs), anti-HCV antibody test and liver ultrasonography were done. Results are as follows; 1. Result of evaluative examination utilizing only the items defined in Regulation was; There were 75 workers with suspected live. disorder(40.3%), 63 with no liver dysfunction (33.9%), 13 with suspected hepatitis B(7.0%), 10 workers with hepatitis B(5.4%), 10 workers with hepatitis B carrier state(5.4%), 10 with alcoholic liver disorders(5.4%), 5 with fatty liver(2.7%). When alternative diagnostic criteria applying additional examination items (drinking history, body mass index, anti-HCV antibody and ultrasonography) diagnosability of liver disorder was increased. When all four items were included, final results were; 23 workers (17.8%) with hepatitis B (10 carriers, 13 suspects and 10 hepatitis B), 10 (5.4%) with hepatitis C(4 carriers, 5 suspects and 1 hepatitis C), 13(7.0%) with alcoholic liver disorder, 45(24.2%) with fatty liver (40 suspects, 5 fatty liver), 410%) with suspected liver disorders and 44 (23.7%) with normal liver. 2. Of examination items defined by Regulation, only SGOT, SGPT, $\gamma$-GTP and HBsAg were significantly different in abnormal rate and mean value, and all other laboratory findings did not showed significant difference between two groups. Drinking history, body mass index and anti-HCV antibody test which are the items that authors included in this study, also showed significant difference between two groups. Utilization of body mass index (BMI) for abnormal liver function group in diagnosis of fatty liver had high specificity (97.6%) but sensitivity (22.3%) was low. Therefore we suggest that SGOT, SGPT, $\gamma$-GTP, HBsAg, alcohol drinking history, BMI and anti-HCV Ab were useful for diagnosis of liver disorders among worker's periodic health examination.

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Treatment of the Headache (두통의 치료)

  • Chung, Kyung-Cheon
    • Korean Journal of Psychosomatic Medicine
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    • v.7 no.2
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    • pp.263-273
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    • 1999
  • Headache is a symptom with varied etiologies and extraordinarily frequent. Headaches can be a symptom of another diseases, such as meningitis, subarachnoid hemorrhage or brain tumor, may represent the disease entity itself as the case in migraine. The international Headache Society criteria were the first to distinguish between primary and secondary headache disorders. When evaluating a patient who presents with headache, the physician abviously needs to identify or exclude the myriad conditions that can cause secondary headache and initial diagnostic workup should be considered. If patient meets the criteria for a primary headache disorder, treatment commonly initiated without additional neurodiagnostic tests. The headache type, its associated feature, and the duration and the intensity of the pain attack all can influence the choice of acute therapy in migraine. Pharmacologically, such as NSAIDs, combination analgesics, vasoactive antimigraineous drugs, neuroleptics, antidepressants, or corticosteroids. Other approches to managing headache include a headache diary to identify triggers, biofeedback, relaxation technique and behavioral modification. Daily preventive medication should be considered by his attack frequency and intensity, and maintained for 4 to 6 months. Tension-type headaches are distinguished between episodic and chronic tension-type headache, but physician must make sure that patient is not drug-overuse or independent during symptomatic abortive therapy or preventive medication. The most difficult headache patients to treat are those with chronic daily headache. They often have physical dependency, low frustration tolerance, sleep problems, and depression. So discontinuation of overused medication is crucial. New developments in migraine therapy are broadening the scope of abortive and prophylactic treatment choices available to the physician. The enhanced ease of the use of sumatriptan and DHE will likely increase patient compliance and satisfaction.

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Food Materials for School Foodservices on High-quality Products, Local Products and Fresh-cut Products - Dietitian's Choice in Elementary, Middle and High Schools in Gyeong-gi Province - (학교급식 식재료로서 지역 농산물, 고품질농산물과 신선편이 채소의 이용현황과 필요에 관한 연구 - 경기지역 초.중.고등학교를 중심으로 -)

  • Kang, Heui-Yun;Jung, Eun-Hee;Rhie, Seung-Gyo
    • The Korean Journal of Community Living Science
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    • v.20 no.3
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    • pp.397-411
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    • 2009
  • The use of local product foods and fresh-cut products, the dietitian's recognition, the required items and the quality for school foodservice was investigated to increase the consumption of high-quality agricultural products. Data from 578 elementary schools, 228 middle schools and 116 high schools were collected by school foodservice personnels in each regional Education Administration in Gyeong-gi province. The first criteria of buying food materials was reliability/safety for all school foodservice. The second criteria were the origin of the product and freshness/ripeness for elementary and middle schools and high school, respectively. The most important consideration for selecting a supplier was the quality of the material. The appearance/status of the food was the first factor for buying food materials. The origin and the seasonality were very important for buying farm products. Dietitians in Gyeong-gi province recognized the local products, and used them weekly. The advantages of using local products were the quick supply, freshness and safety. On the other hand, the disadvantages were the lack of information and the uncertainty of supply. Sixty eight percent of the subjects had experienced the high-quality agricultural products in school meals, but the frequency was low. The main reasons for not servicing high-quality agricultural products were the high cost and the lack of trust on the quality. Among fresh-cut products, seasonings and root vegetables were purchased most frequently, but leaf vegetables was 5.7% only. The purchase of fresh-cut products was not frequent, but usually satisfied. The advantages of fresh-cut products were the reduced workload and waste, but the reason for not using them were poor hygiene and the high price. The diverse supply system and the promotion of the local product foods would be necessary since the most food materials were purchased through suppliers. In addition, the problems related to the high cost and distrust should be resolved to expand the consumption of the high-quality agricultural products and the fresh-cut vegetables. The institutions for certifying the quality should be needed to increase the confidence of these products.

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