• Title/Summary/Keyword: 집단간 차이분석

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Effects of Air Pollution on the Pinus thunbergii Forest in the Vicinity of Sasang Industrial Complex in Korea (사상공단(沙上工團) 주변(周邊)의 대기오염(大氣汚染)이 해송림(海松林)에 미치는 영향(影響))

  • Kim, Jeom Soo;Lee, Kang Young
    • Journal of Korean Society of Forest Science
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    • v.83 no.4
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    • pp.486-497
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    • 1994
  • The objective of this study was to examine the effects of air pollution on Pinus thunbergii forests surrounding Sasang industrial complex in Korea. The injury index, contents of chlorophyll and mineral elements, and concentrations of water soluble sulfur in needles were investigated at sample plots surrounding industrial complex and compared with those of control far from industrial complex. The results obtained are as follows ; 1. Discoloration of Pinus thunbergii needles was severe in the vicinity of industrial complex, and the older needle age classes was the more severe its injury appeared. Injury index was increased in the vicinity of industrial complex. 2. Water-soluble sulfur concentration was high in the vicinity of industrial complex at all of needle age classes, and those of all plots were higher than that of control. 3. Chlorophyll a contents were lower at surrounding industrial complex than that at control. It was supposed that chlorophyll a was destroyed by air pollutants. Total chlorophyll contents and content ratio of chlorophyll a to b were influenced by decrease of chlorophyll a contents. 4. Phosphorus contents in needles were decreased even in remoted regions with the increase of needle age classes. Colcium contents in needles were decreased near industrial complex at all needle ages classes. 5. There were negative correlation, between injury index and chlorophyll contents, injury index and calcium contents, and there were positive correlation between injury index and calcium contents. 6. Cluster analysis was carried out to divide the injured regions on sample plots. As a result of the analysis, there were devided 3 regions, severe regions(1-8 plots), medium regions(9, 10, 11, 12, 15, 17 plot), slight(13, 14, 16, 18, 19 plot and control). 7. The cross section of visible injured needle showed the destruction of mesophyll cell, sclerenchyma cell in the outside of resin duct and endodermis, partially.

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Evaluation on the Accuracy of Targeting Error Correction Through the Application of Target Locating System in Robotic CyberKnife (로봇 사이버나이프에서 위치인식시스템을 이용한 Targeting Error값 보정의 정확성 평가)

  • Jeong, Young-Joon;Jung, Jae-Hong;Lim, Kwang-Chae;Cho, Eun-Ju
    • The Journal of Korean Society for Radiation Therapy
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    • v.21 no.1
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    • pp.1-7
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    • 2009
  • Purpose: The purpose is to evaluate the accuracy of correcting the targeting error through the Target Location System (TLS) for the location change error of the reference point which arises from the movement or motion of patient during the treatment using the CyberKnife. Materials and Methods: In this test, Gafchromic MD-55 film was inserted into the head and neck phantom to analyze the accuracy of the targeting, and then the 6 MV X-ray of CyberKnife (CyberKnife Robotic Radiosurgery System G4, Accuray, US) was irradiated. End to End (E2E) program was used to analyze the accuracy of targeting, which is provided by Accuray Corporation. To compute the error of the targeting, the test was carried out with the films that were irradiated 12 times by maintaining the distance within the rage of $0{\pm}0.2\;mm$ toward x, y, z from the reference point and maintaining the angle within the rage of $0{\pm}0.2^{\circ}$ toward roll, pitch, yaw, and then with the films which were irradiated 6 times by applying intentional movement. And the correlation in the average value of the reference film and the test film were analyzed through independent samples t-test. In addition, the consistency of dose distribution through gamma-index method (dose difference: 3%) was quantified, compared, and analyzed by varying the distance to agreement (DTA) to 1 mm, 1.5 mm, 2 mm, respectively. Results: E2E test result indicated that the average error of the reference film was 0.405 mm and the standard deviation was 0.069 mm. The average error of the test film was 0.413 mm with the standard deviation of 0.121 mm. The result of independent sampling t-test for both averages showed that the significant probability was P=0.836 (confidence level: 95%). Besides, by comparing the consistency of dose distribution of DTA through 1 mm, 1.5 mm, 2 mm, it was found that the average dose distribution of axial film was 95.04%, 97.56%, 98.13%, respectively in 3,314 locations of the reference film, consistent with the average dose distribution of sagittal film that was 95.47%, 97.68%, 98.47%, respectively. By comparing with the test film, it was found that the average dose distribution of axial film was 96.38%, 97.57%, 98.04%, respectively, at 3,323 locations, consistent with the average dose distribution of sagittal film which was 95.50%, 97.87%, 98.36%, respectively. Conclusion: Robotic CyberKnife traces and complements in real time the error in the location change of the reference point caused by the motion or movement of patient during the treatment and provides the accuracy with the consistency of over 95% dose distribution and the targeting error below 1 mm.

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Identification of Domesticated Silkworm Varieties Using a Whole Genome Single Nucleotide Polymorphisms-based Decision Tree (전장유전체 SNP 기반 decision tree를 이용한 누에 품종 판별)

  • Park, Jong Woo;Park, Jeong Sun;Jeong, Chan Young;Kwon, Hyeok Gyu;Kang, Sang Kuk;Kim, Seong-Wan;Kim, Nam-Suk;Kim, Kee Young;Kim, Iksoo
    • Journal of Life Science
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    • v.32 no.12
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    • pp.947-955
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    • 2022
  • Silkworms, which have recently shown promise as functional health foods, show functional differences between varieties; therefore, the need for variety identification is emerging. In this study, we analyzed the whole silkworm genome to identify 10 unique silkworm varieties (Baekhwang, Baekok, Daebaek, Daebak, Daehwang, Goldensilk, Hansaeng, Joohwang, Kumkang, and Kumok) using single nucleotide polymorphisms (SNP) present in the genome as biomarkers. In addition, nine SNPs were selected to discriminate between varieties by selecting SNPs specific to each variety. We subsequently created a decision tree capable of cross-verifying each variety and classifying the varieties through sequential analysis. Restriction fragment length polymorphism (RFLP) was used for SNP867 and SNP9183 to differentiate between the varieties of Daehwang and Goldensilk and between Kumkang and Daebak, respectively. A tetra-primer amplification refractory (T-ARMS) mutation was used to analyze the remaining SNPs. As a result, we could isolate the same group or select an individual variety using the nine unique SNPs from SNP780 to SNP9183. Furthermore, nucleotide sequence analysis for the region confirmed that the alleles were identical. In conclusion, our results show that combining SNP analysis of the whole silkworm genome with the decision tree is of high value as a discriminative marker for classifying silkworm varieties.

CT Follow-Up of Postoperative Bronchopleural Fistula: Risk Factors for Progression to Chronic Complicated Infection (수술 후 기관지 흉막루의 전산화단층촬영 추적 검사: 만성 복합성 감염 진행의 위험인자 분석)

  • Ji-Yeon Han;Ki-Nam Lee;Yoo Sang Yoon;Jihyun Lee;Hongyeul Lee;Seok Jin Choi;Hye Jung Choo;Jin Wook Baek;Young Jin Heo;Gi Won Shin;Jinyoung Park;Dasom Kim
    • Journal of the Korean Society of Radiology
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    • v.82 no.1
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    • pp.128-138
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    • 2021
  • Purpose We evaluated the risk factors for progression to chronic complicated bronchopleural fistula (BPF) after pulmonary resection using follow-up CT. Materials and Methods We retrospectively reviewed 45 cases with BPF that had undergone pulmonary resection during 2010-2018. We compared the clinical and radiological characteristics of those with complicated BPF (n = 24) and those without complicated (sterilized) BPF (n = 21). The clinical and radiological risk factors for progression to chronic complicated BPF were examined by logistic regression analysis. Results The thickness of the pleural cavity wall (p = 0.022), the size of the pleural cavity (p = 0.029), and the size increase of BPF on follow-up (p = 0.012) were significantly different between the two groups. The risk factors for progression to chronic complicated BPF were age > 70 years (odds ratio, 6.43; 95% confidence interval, 1.2-33.7), the thickness of the cavity wall > 5 mm (odds ratio, 52.5; 95% confidence interval, 5.1-545.4), and an increase in the size of the pleural cavity on follow-up CT (odds ratio, 12.5; 95% confidence interval, 2.1-73.5), only in the univariate analysis. Conclusion The risk factors for progression to chronic complicated BPF can be evaluated using follow-up CT.

Sex- and age group-specific associations between intakes of dairy foods and pulses and bone health in Koreans aged 50 years and older: Based on 2008~2011 Korea National Health and Nutrition Examination Survey (50세 이상 한국인의 성·연령군별 우유류와 두류 섭취량과 골 건강과의 관련성 : 2008~2011 국민건강영양조사 자료를 이용하여)

  • Seo, Hyun-Bi;Choi, Young-Sun
    • Journal of Nutrition and Health
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    • v.49 no.3
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    • pp.165-178
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    • 2016
  • Purpose: This study was performed to examine associations of intakes of milk and dairy products, pulses, and soy foods with bone health in Koreans aged 50 yr and older. Methods: A total of 3,201 men and 3,581 women aged 50 yr and older who participated in the 2008~2011 Korea National Health and Nutrition Examination Survey were grouped by sex and age groups of 50~64 yr and 65 yr and older. Subjects within each sex and age group were divided into three bone health groups: normal, osteopenia, and osteoporosis groups based on bone mineral density. Intakes of nutrients and foods derived from 24-hour recall data were compared among three bone health groups. Associations between intake frequencies of foods, including milk, yogurt, tofu, or soy milk, and osteoporosis risk were evaluated based on confounding risk factor-adjusted logistic regression. Results: Calcium intake was in the order of normal, osteopenia, and osteoporosis in men (p < 0.01) and women (p < 0.05) aged 50~64 yr as well as in men aged 65 yr and older (p < 0.001). In women aged 50~64 yr, intake of milk and dairy products was lower in the osteoporosis group (p < 0.01) as compared with the osteopenia group. Intake of pulses or tofu was not significantly different among bone health groups. Odds ratio (OR) for milk intake frequency (${\geq}2$ times/week) compared to intake frequency less than 1 time/month was 0.45 (95% CI 0.24~0.85, p for trend = 0.022) in men aged 65 yr and older. The OR for yogurt intake frequency (1 time/month~1 time/week) was 0.47 (95% CI 0.30~0.73, p for trend = 0.019) in women aged 50~64 yr. Intake frequency of tofu or soy milk was not associated with reduced risk of osteoporosis in all groups. Conclusion: Dairy food intake was significantly associated with bone health, and its effect was sex- and age group-specific, whereas soy food intake was not. Dietary intervention to prevent osteoporosis would be effective for women aged 50~64 yr old and for men aged 65 yr and older.

Effects of Electronic Security Service Quality Satisfaction and Customer Satisfaction on Switching Barrier and Customer Loyalty (기계경비 서비스품질만족과 고객만족이 전환장벽 및 고객충성도에 미치는 영향)

  • Kim, Chang-Ho;Yoon, Jong-Dae;Jung, Chul-Kyu;Lee, Bong-Keun
    • Korean Security Journal
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    • no.36
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    • pp.111-137
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    • 2013
  • The purpose of this study is to examine the effects of electronic security service quality satisfaction and customer satisfaction on switching barrier and customer loyalty. Survey questionnaires were distributed to business owners in Seoul that are using electronic security system and the total of 500 copies were used as research data except 60 copies with insufficient responses. The results are as follow. First, as for the effects of electronic security service quality satisfaction on electronic security customer satisfaction, it indicates that the higher electronic security service quality satisfaction achieves, the more it has positive effects on electronic security customer satisfaction. Second, as for the effects of electronic security service quality satisfaction on switching cost, it indicates that the higher electronic security service quality satisfaction achieves, the more it has positive effects on switching cost. As for the effects of electronic security service quality satisfaction on human relations, it indicates that the higher electronic security service quality satisfaction achieves, the more it has positive effects on human relations. It indicates that the effects of electronic security service quality satisfaction on alternative attraction was not meaningful. Third, as for the effects of electronic security customer satisfaction on switching cost, it indicates that the higher electronic security customer satisfaction achieves, the more it has positive effects on switching cost. As for the effects of electronic security customer satisfaction on human relations, it indicates that the higher electronic security customer satisfaction achieves, the more it has positive effects on human relations. But, it indicates that the effects of electronic security customer satisfaction on alternative attraction was not meaningful. Fourth, As for the effects of electronic security service quality satisfaction and electronic security customer satisfaction on customer loyalty, it indicates that the higher electronic security service quality satisfaction achieves, the more it has positive effects on customer loyalty. As for the effects of switching cost on customer loyalty, it indicates that the higher switching cost achieves, the more it has positive effects on customer loyalty. As for the effects of alternative attraction on customer loyalty, it indicates that there is no meaningful relation between alternative attraction and customer loyalty. But, effects of human relations on customer loyalty, it indicates that there is no meaningful relation between human relations and customer loyalty. Based on the above results, it is noticeable that in the effects of electronic security service quality satisfaction and electronic security customer satisfaction on switching barrier, all of them had meaningful effects except for alternative attractiveness. This signifies that switching barrier factor can increase when the service quality of electronic security and customer satisfaction increase. In other words, it can be said that increased awareness of electronic security service quality satisfaction and electronic security customer satisfaction by electronic security users can lead to high customer loyalty by establishing switching barrier through such increased awareness.

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Differences of Illness Behavior in Depressive Patients According to the Presence of Somatization (우울증 환자에서 신체화 증상에 따른 질병행동의 차이)

  • Yoon, Chang-Young;Jang, Se-Heon;Jae, Young-Myo;Lee, Dae-Su;Choi, Jin-Hyuk
    • Korean Journal of Psychosomatic Medicine
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    • v.17 no.2
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    • pp.68-74
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    • 2009
  • Objectives : Illness behavior is defined as the persistence of an adaptive/maladaptive mode of perceiving, evaluating and responding to health status and symptoms according to the status. In a cognitive aspect, somatizing symptoms are regarded as being originated from distortions, including magnification and/or amplification, of perceiving, evaluating and responding to symptoms such as bodily sensations. That is somatization may be explained by maladaptive illness behavior. In this study, we tried to investigate differences of illness behavior in depressive patient according to the presence of somatization. Methods : We divided 45 patients who were diagnosed as depression with ICD-10 diagnostic criteria into two groups(somatizing and non-somatizing group) according to the somatization subscale of Korean Depression Scale and compared two groups in the differences of illness behavior using the Illness Behavior Questionnaire. Results : Somatizing group showed significantly higher scores than non-somatizing group on the disease affirmation subscale($6.79{\pm}2.08$ vs. 4.76, p=0.003) and the denial subscale($3.25{\pm}1.22$ vs. $2.10{\pm}1.41$, p=0.006). There were no significant differences between two groups on the general hypochondriasis subscale and the affective unstability subscale. In a logistic regression analysis, somatizing group also showed higher odds ratio (OR) scores on the disease affirmation subscale(OR=1.418, p=0.089) and the denial subscale(OR=1.880, p=0.083). Conclusion : The disease affirmation and denial may be a discriminative mechanism of somatization in depressive patients. These subscales of Illness Behavior Questionnare could be useful markers, and psychiatric illnesses with somatizing and depressive symptoms may be differentially diagnosed and be predicted through these subscales.

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Comparative Study between Mathematically Gifted Elementary Students and Common Students in Self-Efficacy and Career Attitude Maturity (초등수학영재와 일반학생의 자기효능감과 진로태도성숙과의 관계 비교)

  • Lee, Jung Hwa;Ryu, Sung Rim
    • Communications of Mathematical Education
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    • v.27 no.1
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    • pp.63-80
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    • 2013
  • Reflecting the recent trends and needs of gifted education, this study set out to compare and analyze mathematically gifted elementary students and common students in self-efficacy and career attitude maturity, understand the characteristics of the former, and provide assistance for career education for both the groups. The subjects include 237 mathematically gifted elementary students and 221 common students in D Metropolitan City. The research findings were as follows: First, mathematically gifted elementary students turned out to have higher self-efficacy than common students at the significance level of .01 in the three self-efficacy subfactors, namely confidence, self-regulated efficacy, and task difficulty preference. The findings indicate that mathematically gifted elementary students have much confidence in themselves and strong faith in themselves, thus forming a habit of preferring a relatively high-level task by taking self-management and task difficulty into proper consideration. Second, mathematically gifted elementary students showed higher overall career attitude maturity than common students. There was significant difference at the significance level of .01 in decisiveness and preparedness between the two groups and significant difference at the significance level of .05 in assertiveness. However, there was no statistically significant difference in purposefulness and independence between the two groups. Finally, there were positive correlations at the significance level of .01 between all the subfactors of self-efficacy and those of career attitude maturity in all the subjects except for self-regulated efficacy and purposefulness, between which there were positive correlations at the significance level of .05. The mathematically gifted elementary students showed positive correlations between more subfactors of self-efficacy and career attitude maturity than common students. Given those findings, it is necessary to take differences in self-efficacy and career attitude maturity between mathematically gifted elementary students and common students into account when organizing and running a curriculum. The findings confirm the importance of providing students with various experiences fit for them and point to a need for helping mathematically gifted elementary students maintain a high level of self-efficacy and guiding them through career education with more appropriate career attitude maturity improvement programs.

A Study on Reputation as Corporate Asset (기업자산으로서의 기업명성가치 연구: 국내 4개 기업 슈퍼브랜드와 기업명성, 미디어 이용간 관련성을 중심으로)

  • Lee, Cheol-Han;Cha, Hee-Won
    • Korean journal of communication and information
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    • v.30
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    • pp.203-237
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    • 2005
  • The purpose of this study is to find a model that can measure the public relations programs based on the assumption that the public relations should aim to lift the corporate reputation. It is a trend that corporate's activities are to be measured from the standpoint of cost-benefit efficiency. However, public relations fields in Korea is left behind this trend because the fields lack in sophisticated model. In order to fill this gap, the researchers introduce the reputation measurement model that can calculate individual corporate public relations programs. In addition, this reputation model Is applied to Korean companies with the expectation of producing a PR index which ran be used to measure the reputation as corporate asset, or superbrand. This study examines the effects of superbrand on consumers according to the media use. Based on the expert group interviews and surveys on consumers, the factors of reputation are drawn. These factors contribute to find reputation model and measurement index which are again applied to measure the Korean companies' public relations programs. Using superbrand as dependent variables and managing abilities, corporate responsibility, corporate communication, and product/employee quality, this study seeks to find which factor specifically attribute to lift corporate reputation. Results show that each factor influences the corporate reputation positively. In addition, the researchers find that media use is moderately related to the superbrand building process in cognitive dimension.

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Mobile Phone Uses and Social-Psychological Variables of Teen-Agers (청소년들의 이동전화 이용행태와 사회심리적 변인에 관한 연구: 부산.울산 지역 이용자들을 중심으로)

  • Lee, Joon-Ho;Ann, Soo-Geun;Jeong, Yong-Jo
    • Korean journal of communication and information
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    • v.27
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    • pp.247-282
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    • 2004
  • The purpose of this study is to examine the mobile phone service usage patterns of Korean teenagers and their motivation to use it, and to explore the relationships between the teenagers' social-psychological characteristics and their trails of mobile phone usage. After reviewing prior theoretical studios, three hypotheses regarding the research questions shown above were generated. Questionnaire study was conducted with 400 high school students in Busan and Ulsan metropolitan areas. They were to answer three categories of questions, such as frequencies of voice calls and text messaging services and the other mobile services, questions asking their social-psychological characteristics, and their motivations for using mobile phone services. Findings show that the teenagers more likely to tend to use voice calls when communicating family members. They tend to avoid those services with high rate of use as multimedia, game, and broadcasting services via mobile phones. The teenagers use mobile phone services for the similar purposes to conventional telephone uses. Therefore, the classical theories showing the alternative purposes or motivations to use conventional telephone usage, which divided the main purposes for phone uses in to two; work/instrumental and socializing/entertaining, proved to be reasonable. The cheap messaging services with texts are popular among the teenagers and are used for socializing/entertaining purposes rather than instrumental/functional purposes. In addition, the teenagers' social-psychological characteristicss are significantly associated with the amount of mobile phone uses. A characteristic of "individual-centeredness" is positively related with non-voice service uses, while "group-centeredness" explains heavy amount of using voice calls and text messaging services. Such characteristics as "immediacy," "directness," "innovativeness," and "other-direction" are positively associated with the frequencies and amounts of mobile phone uses, while "inner-direction" and "tradition-direction" are negatively correlated.

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