• Title/Summary/Keyword: surveillance test

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The evaluation of properties for radiation therapy techniques with flattening filter-free beam and usefulness of time and economy to a patient with the radiation therapy (Flattening filter-free beam을 이용한 방사선 치료 기법의 특성 및 환자의 시간적.경제적 유용성 평가)

  • Goo, Jang Hyeon;Won, Hui Su;Hong, Joo Wan;Chang, Nam Jun;Park, Jin Hong
    • The Journal of Korean Society for Radiation Therapy
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    • v.26 no.2
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    • pp.363-368
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    • 2014
  • Purpose : The aim of this study was to appraise properties for radiation therapy techniques and effectiveness of time and economy to a patient in the case of applying flattening filter-free (3F) and flattening filter (2F) beam to the radiation therapy. Materials and Methods : Alderson rando phantom was scanned for computed tomography image. Treatment plans for intensity modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT) and stereotactic body radiation therapy (SBRT) with 3F and 2F beam were designed for prostate cancer. To evaluate the differences between the 3F and 2F beam, total monitor units (MUs), beam on time (BOT) and gantry rotation time (GRT) were used and measured with $TrueBeam^{TM}$ STx and Surveillance And Measurement (SAM) 940 detector was used for photoneutron emitted by using 3F and 2F. To assess temporal and economical aspect for a patient, total treatment periods and medical fees were estimated. Results : In using 3F beam, total MUs in IMRT plan increased the highest up to 34.0% and in the test of BOT, GRT and photoneutron, the values in SBRT plan decreased the lowest 39.8, 38.6 and 48.1%, respectively. In the temporal and economical aspect, there were no differences between 3F and 2F beam in all of plans and the results showed that 10 days and 169,560 won was lowest in SBRT plan. Conclusion : According as the results, total MUs increased by using 3F beam than 2F beam but BOT, GRT and photoneutron decreased. From above the results, using 3F beam can decrease intra-fraction setup error and risk of radiation-induced secondary malignancy. But, using 3F beam did not make the benefits of temporal and economical aspect for a patient with the radiation therapy.

Development of Work-related Musculoskeletal Disorder Questionnaire Using Receiver Operating Characteristic Analysis (Receiver Operating Characteristic 분석법을 이용한 업무관련성 근골격계질환 설문지 개발)

  • Kwon, Ho-Jang;Ju, Yeong-Su;Cho, Soo-Hun;Kang, Dae-Hee;Sung, Joo-Hon;Choi, Seong-Woo;Choi, Jae-Wook;Kim, Jae-Young;Kim, Don-Gyu;Kim, Jai-Yong
    • Journal of Preventive Medicine and Public Health
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    • v.32 no.3
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    • pp.361-373
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    • 1999
  • Objectives: Receive Operating Characteristic(ROC) curve with the area under the ROC curve(AUC) is one of the most popular indicator to evaluate the criterion validity of the measurement tool. This study was conducted to develop a standardized questionnaire to discriminate workers at high-risk of work-related musculoskeletal disorders using ROC analysis. Methods: The diagnostic results determined by rehabilitation medicine specialists in 370 persons(89 shipyard CAD workers, 113 telephone directory assistant operators, 79 women with occupation, and 89 housewives) were compared with participant's own replies to 'the questionnair on the worker's subjective physical symptoms'(Kwon, 1996). The AUC's from four models with different methods in item selection and weighting were compared with each other. These 4 models were applied to 225 persons, working in an assembly line of motor vehicle, for the purpose of AUC reliability test. Results: In a weighted model with 11 items, the AUC was 0.8155 in the primary study population, and 0.8026 in the secondary study population(p=0.3780). It was superior in the aspects of discriminability, reliability and convenience. A new questionnaire of musculoskeletal disorder could be constructed by this model. Conclusion: A more valid questionnaire with a small number of items and the quantitative weight scores useful for the relative comparisons are the main results of this study. While the absolute reference value applicable to the wide range of populations was not estimated, the basic intent of this study, developing a surveillance fool through quantitative validation of the measures, would serve for the systematic disease prevention activities.

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Object Tracking Based on Exactly Reweighted Online Total-Error-Rate Minimization (정확히 재가중되는 온라인 전체 에러율 최소화 기반의 객체 추적)

  • JANG, Se-In;PARK, Choong-Shik
    • Journal of Intelligence and Information Systems
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    • v.25 no.4
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    • pp.53-65
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    • 2019
  • Object tracking is one of important steps to achieve video-based surveillance systems. Object tracking is considered as an essential task similar to object detection and recognition. In order to perform object tracking, various machine learning methods (e.g., least-squares, perceptron and support vector machine) can be applied for different designs of tracking systems. In general, generative methods (e.g., principal component analysis) were utilized due to its simplicity and effectiveness. However, the generative methods were only focused on modeling the target object. Due to this limitation, discriminative methods (e.g., binary classification) were adopted to distinguish the target object and the background. Among the machine learning methods for binary classification, total error rate minimization can be used as one of successful machine learning methods for binary classification. The total error rate minimization can achieve a global minimum due to a quadratic approximation to a step function while other methods (e.g., support vector machine) seek local minima using nonlinear functions (e.g., hinge loss function). Due to this quadratic approximation, the total error rate minimization could obtain appropriate properties in solving optimization problems for binary classification. However, this total error rate minimization was based on a batch mode setting. The batch mode setting can be limited to several applications under offline learning. Due to limited computing resources, offline learning could not handle large scale data sets. Compared to offline learning, online learning can update its solution without storing all training samples in learning process. Due to increment of large scale data sets, online learning becomes one of essential properties for various applications. Since object tracking needs to handle data samples in real time, online learning based total error rate minimization methods are necessary to efficiently address object tracking problems. Due to the need of the online learning, an online learning based total error rate minimization method was developed. However, an approximately reweighted technique was developed. Although the approximation technique is utilized, this online version of the total error rate minimization could achieve good performances in biometric applications. However, this method is assumed that the total error rate minimization can be asymptotically achieved when only the number of training samples is infinite. Although there is the assumption to achieve the total error rate minimization, the approximation issue can continuously accumulate learning errors according to increment of training samples. Due to this reason, the approximated online learning solution can then lead a wrong solution. The wrong solution can make significant errors when it is applied to surveillance systems. In this paper, we propose an exactly reweighted technique to recursively update the solution of the total error rate minimization in online learning manner. Compared to the approximately reweighted online total error rate minimization, an exactly reweighted online total error rate minimization is achieved. The proposed exact online learning method based on the total error rate minimization is then applied to object tracking problems. In our object tracking system, particle filtering is adopted. In particle filtering, our observation model is consisted of both generative and discriminative methods to leverage the advantages between generative and discriminative properties. In our experiments, our proposed object tracking system achieves promising performances on 8 public video sequences over competing object tracking systems. The paired t-test is also reported to evaluate its quality of the results. Our proposed online learning method can be extended under the deep learning architecture which can cover the shallow and deep networks. Moreover, online learning methods, that need the exact reweighting process, can use our proposed reweighting technique. In addition to object tracking, the proposed online learning method can be easily applied to object detection and recognition. Therefore, our proposed methods can contribute to online learning community and object tracking, detection and recognition communities.

Molecular identification and clinical features of enteroviral infection in children of central Korea: An overview of enteroviral epidemiology between spring 2005 and autumn 2006 (2005년 봄부터 2006년 가을까지 국내 중부지역의 enterovirus 감염의 분자유전학 조사와 임상양상)

  • Roh, Eui Jung;Jin, Yong Man;Chung, Eun Hee;Chang, Young Pyo;Park, Woo Sung;Park, Kwisaung;Jee, Young Mee
    • Clinical and Experimental Pediatrics
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    • v.52 no.11
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    • pp.1234-1240
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    • 2009
  • Purpose:Enteroviruses (EVs) are commonly known to cause infection, especially in infants and children. This report presents an overview of enterovirus epidemiology in central Korea. Methods:From the spring of 2005 to the autumn of 2006, we collected the cerebrospinal fluid (CSF) and stool samples from the pediatric patients with a febrile illness or suspected meningitis who were admitted to hospitals in central Korea. In order to test for EVs, cell lines were derived from pretreated susceptible specimen, and the cytopathic effects were observed. Seminested real time-polymerase chain reaction (RT-PCR) and direct sequencing were performed for genotypic and phylogenetic analyses. Results:Of the 305 patients examined, 51 (16.7%) tested positive for EV. Of these 51 patients, 44 showed the following serotypes: Echovirus (ECV) 18 (18 cases, 35.2%), Coxsackievirus B (CVB) 5 (13 cases, 25.4%), ECV25 (5 cases, 9.8%), ECV9 (4 cases, 7.8%), ECV5 (3 cases, 5.8%), and EV74 (1 case, 1.9%). In 2005, between June and August, ECV18 and CVB5 were mostly responsible for the enteroviral infections among the patients in central Korea. In 2006, between July and August, ECV25 was mostly the cause of enteroviral infection. Conclusions:There is a need for continuous surveillance of enteroviral infection and its clinical manifestations, particularly for EV74, which was first identified in Korea.

Application of mix LPS-ELISA for monitoring of antibodies to major serogroups of Salmonella in animal (Mix LPS-ELISA법을 이용한 살모넬라균 복합감염항체 동시 모니터링)

  • Lee, Hee-soo;Im, Suk-kyoung;Woo, Seng-ryong;Yi, You-young;Kim, Jong-yeom;Joo, Yi-seok;Kim, Jong-man
    • Korean Journal of Veterinary Research
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    • v.38 no.4
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    • pp.793-802
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    • 1998
  • Salmonellosis caused by a number of serotypes of Salmonella is an infectious, acute or chronic, zoonotic disease and characterized by enteritis and diarrhea, septicemia in animal. In these studies we investigated the prevalent serotypes of Salmonella causing animal salmonellosis in Korea and the 71 strains of Salmonella spp. were isolated from materials such as mesenteric lymph nodes, fecal samples from slaughtered animal. With the identification test results, the most prevalent serotypes were, in order, S stanley 31 strains (43.7%), S typhimurium 19 strains (26.8%) and S montevideo 11 strains (15.5%), respectively. And we could establish the method for detection of antibodies to broad variety of Salmonella serotypes. Lipopolysaccharide(LPS) antigen extracted from Salmonella was more sensitive and specific than outer membrane protein antigen from that for detection of Salmonella antibody by using an indirect ELISA. The optimal concentration of antigen was 100ng/ml of LPS, the dilutions of conjugate and serum were 1 : 1,000~2,000 and 1 : 200~400, respectively. The mix LPS-ELISA which was used by mixing LPS from S typhimurium (group B), S choleraesuis (group C) and S enteritidis (group D) were more rapid and effective than that used LPS from individual strain for detection of Salmonella serogroup O4, O7 and O9 antibody at the same time. We could obtain the high values of optical density ($0.73{\pm}0.32$) by mix LPS-ELISA on the farm which had occurred salmonellosis, but very low values of $0.17{\pm}0.06$ on the negative farm of salmonellosis. So, the mix LPS-ELISA may be used to monitor the serological surveillance for the presence of infection with a number of serotypes of Salmonella and would be useful for prevention and control of salmonellosis in animal.

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A study on the formation process of opportunism in strategic alliance (전략적 제휴에서의 기회주의행동 유발과정에 관한 연구)

  • Kang, Inwon;Park, Kyungsin
    • International Commerce and Information Review
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    • v.17 no.3
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    • pp.225-250
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    • 2015
  • While strategic alliance of multinational corporation has boost, opportunistic behavior is also increased recently. This study examines the cause of opportunism in strategic alliance by focusing on the development of opportunistic behavior, a process in which resource complementarity and risk perception decides attitudinal direction, ultimately leading to opportunism. Empirical test based on 257 alliance participants shows that risk perception had a greater influence on firms' attitudinal and behavioral directions compared to benefit perception. Notably, relational risk heavily influenced firms' competitive attitude and opportunistic behavior. Finally, the study concludes that firms' competitive and independent attitude caused by risk perception negatively influence alliance outcome. Based on the results, it is drawn that alongside the external tools such as surveillance, control, monitoring or legalistic pleas, management of risk perception during the alliance process has significance influence on the achievement of alliance goals.

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The Prevalence and Risk Factors of Drug Resistant Pulmonary Tuberculosis Investigated at One University Hospital in Seoul (서울지역 한 대학병원에서 조사된 폐결핵 약제 내성률 및 위험인자)

  • Kim, Do Kyun;Kim, Mi Ok;Kim, Tae-Hyung;Sohn, Jang Won;Yoon, Ho Joo;Shin, Dong Ho;Park, Sung Soo
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.3
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    • pp.243-247
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    • 2005
  • Background : The prevalence of tuberculosis is slowly decreasing in Korea. However, the drug-resistance of pulmonary tuberculosis is a major risk factor of treatment failure. Moreover, the National Surveillance System has recently been discontinued. Therefore, a continuous survey is necessary for the exact detection of the rate of drug resistance. We studied the recent 4-year drug resistance rate of tuberculosis at a single University hospital in Seoul. Materials and Methods : The study included 239 pulmonary tuberculosis patients performed with a tuberculosis culture and a drug-sensitivity test at Hanyang University Medical Center from March 1999 to March 2003. Results : Of the 239 patients included in the study during the 4-year period, 52 patients showed resistance to one or more anti-tuberculosis drug (21.8%). The rate of multi-drug resistance was 12.6%. The resistance rates to isoniazid, rifampin, ethambutol, streptomycin and pyrazinamide were 18.4%, 13.8%, 11.7%, 6.7% and 8.4%, respectively. Ninety patients had a history of previous anti-tuberculosis treatment, and the rates of the overall drug resistance and multi-drug resistance of these patients were 36.7% and 25.6%, respectively. The patients with drug-resistance showed a higher rate of a previous tuberculosis treatment history (63.5%) than the drug-sensitive group patients (30.5%). Conclusion : The rate of drug resistant tuberculosis is 21.8%, and multi-drug resistant tuberculosis is 12.6%. The rate of drug resistance is higher in those previously treated for tuberculosis.

Health Care Access and Utilization among Korean American Adults in Alameda County, California: 1994 and 2002

  • Kim, Young-Bok;Moskowitz, Joel M.;Lee, Hyun-Ju;Kazinets, Yevgeniy
    • Korean Journal of Health Education and Promotion
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    • v.23 no.5
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    • pp.29-46
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    • 2006
  • Purpose: Since 1994, Asian Health Services, the Korean American Community Advisory Board, and the Center for Family and Community Health (University of California at Berkeley) have conducted periodic, population-based surveys on Korean American community health in Alameda County, California. The present study examines changes in health care access and utilization between 1994 and 2002 among Korean American adults in Alameda County, California. Method: We reanalyzed data from the 1994 and 2002 Korean Health Surveys. The primary variables of interest, health care access and utilization, were operationalized in terms of health insurance coverage, routine check-ups, a usual source of health care and reported barriers to health care. The frequency distribution of each indicator was calculated and its standard error was estimated using SUDAAN. The differences between 1994 and 2002 were examined with chi-square test. Results: Compared to 1994, Korean Americans in Alameda County were more likely to have health insurance coverage in 2002 (74.0% vs. 82.7%). Korean Americans in Alameda County were more likely to have received a recent (prior two years) routine health checkup in 2002 (50.4% vs. 57.2%). Health checkups increased over time for males, for adults with more than 12 years of education, and for employed adults. Also, compared to 1994, employed adults were more likely to have a usual source of health care in 2002 (66.5% vs. 78.4%). In both 1994 and 2002, high cost (58.0% vs. 47.8%) was the most commonly cited barrier to health care, and the next most frequently cited barriers were language (29.2% vs. 27.7%) and no time (29.2% vs. 30.3%). Conclusion: To improve health care utilization and health conditions, it is important to investigate factors related to health care and to monitor changing trends. Ongoing surveillance of health-related factors can contribute to the development of health education programs to reduce morbidity and mortality due to chronic disease, and thereby lead to improvements in health status among Korean Americans.

Improved Radiochemical Yields, Reliability and Improvement of Domestic $^{18}F$-FDG Auto Synthesizer (국산 $^{18}F$-FDG Auto Sysnthesizer의 수율 향상과 성능 개선)

  • Park, Jun-Hyung;Im, Ki-Seop;Lee, Hong-Jin;Jeong, Kyung-Il;Lee, Byung-Chul;Lee, In-Won
    • The Korean Journal of Nuclear Medicine Technology
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    • v.13 no.3
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    • pp.147-151
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    • 2009
  • Purpose: 2-[$^{18}F$]Fluoro-2-deoxy-D-glucose ([$^{18}F$]FDG) particularly plays as a important role in Positron Emission Tomography (PET) imaging in nuclear medicine. Domestic [$^{18}F$]FDG auto synthesizers are installed in Seoul National University Bundang Hospital (SNUBH) at June 2008, these modules were known that it's synthetic yields were guaranteed in average $45{\pm}5%$ so far. To improve yields and convenience of domestic [$^{18}F$]FDG auto synthesizer, numerous trials in reaction time, base concentration, pressure and temperature were performed to increase [$^{18}F$]FDG yields. Materials and Methods: Several synthetic factors (temperature, time and pressure) and shortcoming were corrected based on many evaporation test. Syringe dispensing of tetra-butylammonium bicarbonate (TBAB) was replaced with micro pipette to prepare tetrabutyl ammonium fluoride salt ([$^{18}F$]TBAF). Troublesome refill of liquid nitrogen every 2 hours which was used to protect vacuum system was changed to charcoal cartridge, base guard filter. To monitor the volume of delivered $[^{18}O]OH_2$ from cyclotron by surveillance camera, we set up the volumetric vial on the cover of the module. In addition to, the recovery vial was added in [$^{18}F$]FDG production system to recover [$^{18}F$]FDG loss due to the leak of valve ($V_{13,14}$) in [$^{18}F$]FDG purification process. Results: When we used micro pipette for adding TBAB ($30\;{\mu}L$ in 12% $H_2O$ in acetonitrile), this quantitative dispensation has enabled to improve $5.5{\pm}1.7%$ residual fluorine-18 activity in fluorine separation cartridge compared to syringe adding. Besides, the synthetic yields of [$^{18}F$]FDG has increased $58{\pm}2.6%$ (n=19), $58{\pm}2.9%$ (n=14), $60%{\pm}2.5%$ (n=17) for 3 months. The life cycle of charcoal cartridge and base vacuum was 3 months prior to filling liquid nitrogen every 2 hours and additional side separator can prevent pump corrosion by organic solvent. After setting of volumetric indicator vial, the operator can easily monitor the total volume of irradiated $[^{18}O]OH_2$ from cyclotron. The recovery vial can be used for the stabilizer when an irregular [$^{18}F$]FDG loss was generated by the leak of valves ($V_{13,14}$). Conclusions: We has optimized appropriate synthetic conditions (temperature, time, pressure) in domestic [$^{18}F$]FDG auto synthesizer. In addition to, the remodeling with several accessories improve yields of domestic [$^{18}F$]FDG auto synthesizer with reliable reproducibility.

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Black Hispanic and Black Non-Hispanic Breast Cancer Survival Data Analysis with Half-normal Model Application

  • Khan, Hafiz Mohammad Rafiqullah;Saxena, Anshul;Vera, Veronica;Abdool-Ghany, Faheema;Gabbidon, Kemesha;Perea, Nancy;Stewart, Tiffanie Shauna-Jeanne;Ramamoorthy, Venkataraghavan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9453-9458
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    • 2014
  • Background: Breast cancer is the second leading cause of cancer death for women in the United States. Differences in survival of breast cancer have been noted among racial and ethnic groups, but the reasons for these disparities remain unclear. This study presents the characteristics and the survival curve of two racial and ethnic groups and evaluates the effects of race on survival times by measuring the lifetime data-based half-normal model. Materials and Methods: The distributions among racial and ethnic groups are compared using female breast cancer patients from nine states in the country all taken from the National Cancer Institute's Surveillance, Epidemiology, and End Results cancer registry. The main end points observed are: age at diagnosis, survival time in months, and marital status. The right skewed half-normal statistical probability model is used to show the differences in the survival times between black Hispanic (BH) and black non-Hispanic (BNH) female breast cancer patients. The Kaplan-Meier and Cox proportional hazard ratio are used to estimate and compare the relative risk of death in two minority groups, BH and BNH. Results: A probability random sample method was used to select representative samples from BNH and BH female breast cancer patients, who were diagnosed during the years of 1973-2009 in the United States. The sample contained 1,000 BNH and 298 BH female breast cancer patients. The median age at diagnosis was 57.75 years among BNH and 54.11 years among BH. The results of the half-normal model showed that the survival times formed positive skewed models with higher variability in BNH compared with BH. The Kaplan-Meir estimate was used to plot the survival curves for cancer patients; this test was positively skewed. The Kaplan-Meier and Cox proportional hazard ratio for survival analysis showed that BNH had a significantly longer survival time as compared to BH which is consistent with the results of the half-normal model. Conclusions: The findings with the proposed model strategy will assist in the healthcare field to measure future outcomes for BH and BNH, given their past history and conditions. These findings may provide an enhanced and improved outlook for the diagnosis and treatment of breast cancer patients in the United States.