• 제목/요약/키워드: case - control study

검색결과 6,341건 처리시간 0.032초

역할-기반 접근 제어 정책에서 일시적 권한 위임에 관한 연구 (A Study of Temporary Permission Delegation In Role-Based Access Control Policy)

  • 나상엽
    • 한국컴퓨터산업학회논문지
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    • 제10권1호
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    • pp.21-28
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    • 2009
  • 역할-기반 접근 제어 정책의 경우 조직의 보안 정책을 보다 효율적이고 일관성 있게 관리할 수 있지만 각 역할의 계층에 의하여 권한의 상속이 결정된다. 이 경우, 하위 개념의 역할은 상위 개념의 역할이 가지는 권한을 수행 하여야 하는 경우에 적절히 대처할 수 없고 하위 개념의 역할에 필요한 새로운 권한을 추가해야만 하고 추가되는 권한은 관리자의 권한 제거 작업 이전까지 하위 역할에 귀속되는 문제가 발생한다. 따라서 본 논문에서는 이러한 문제를 해결하기 위하여 역할이 가지는 권한의 일시적인 위임을 통하여 이를 해결하고자 한다. 이를 위하여 권한의 위임을 수행하기 위한 정책과 새로운 역할-권한 관계의 정의, 권한 위임을 위한 새로운 프로토콜을 제시하였다.

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시각무시가 편마비 환자의 운동 기능회복에 미치는 영향 (Effect of Visual neglect for hemiplegia to motor recovery)

  • 김용권
    • 대한물리치료과학회지
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    • 제10권1호
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    • pp.18-29
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    • 2003
  • The purpose of this study by examine the effect of visual neglect on hemiplegia motor recovery are showing trouble which can be raised by visual neglect and helping the patient's ADL and functional recovering. Among the patients who are being taken physical therapy in many other hospitals in Busan From February 1st 2002 to august 31st, we chose 20 patients as control group who did not have symptoms of visual neglect and 20 other patients who did have as case group. We used Albert's test and line bisection as visual neglect test, and MAS as motor recovery. The average age of the patient group is 51.55 and that of control is 44.9. The men's rate is higher than women' s in both groups. Although the rate of left hemiplegia is higher than right hemiplegia in case group, that of right hemiplegia is higher than left hemiplegia in control group. There is much lesion site of basal ganglia in case group. There is the most amount of transformation of MAS when visual neglect is shorter than 1.5centimeter. Each change of MAS point before and after therapy in case group and control group is revealed $6.5{\pm}4.37$ and $12.5{\pm}5.95$.

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산업용 로봇트의 정밀제어를 위한 학습제어 방법의 개발 (A Development of Learning Control Method for the Accurate Control of Industrial Robot)

  • 원광호;허경무
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.346-346
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    • 2000
  • We proposed a method of second-order iterative learning control with feedback, which shows an enhancement of convergence speed and robustness to the disturbances in our previous study. In this paper, we show that the proposed second-order iterative learning control algorithm with feedback is more effective and has better convergence performance than the algorithm without feedback in the case of the existence of initial condition errors. And the convergence woof of the proposed algorithm in the case of the existence of initial condition error is given in detail, and the effectiveness of the Proposed algorithm is shown by simulation results.

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Three-axis Attitude Control for Flexible Spacecraft by Lyapunov Approach under Gravity Potential

  • Bang, Hyo-Choong;Lee, Kwang-Hyun;Lim, Hyung-Chul
    • International Journal of Aeronautical and Space Sciences
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    • 제4권1호
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    • pp.99-109
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    • 2003
  • Attitude control law synthesis for the three-axis attitude maneuver of a flexible spacecraft model is presented in this study. The basic idea is motivated by previous works for the extension into a more general case. The new case includes gravitational gradient torque which has significant effect on a wide range of low earth orbit missions. As the first step, the fully nonlinear dynamic equations of motion are derived including gravitational gradient. The control law design based upon the Lyapunov approach is attempted. The Lyapunov function consists of a weighted combination of system kinetic and potential energy. Then, a set of stabilizing control law is derived from the basic Lyapunov stability theory. The new control law is therefore in a general form partially validating the previous work in some sense.

스마트 하수처리장 도입에 필요한 운전제어기술에 관한 연구 (A Study on Operation Control Technology Required for Introduction of Intelligent Sewage Treatment Plant)

  • 이지원;김유현;길경익
    • 한국습지학회지
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    • 제24권1호
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    • pp.38-43
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    • 2022
  • 스마트(Smart) 하수처리장은 하수처리 전 과정에 대한 ICT 기반의 실시간 모니터링, 원격 제어 관리 및 지능화 체계를 구축하여 안전하고 깨끗한 물환경을 조성하는 것을 의미한다. 이러한 스마트 하수처리장의 핵심이 되는 기술이 계측기를 활용한 운전제어 기술이라 할 수 있다. 본 연구진은 국내에서 진행중인 하수처리장 지능화 연구사업들을 참고하여 지능화사업 구축 시 필요한 운전제어 기술들을 분석하고 제시하였다. 분석 결과 규모별 제어, 반류수 제어, 연계처리수 제어, 약품량 제어, 동절기 운영제어, 총 유기탄소 제어까지 총 6개의 제거 기술에 대해 제시하였다. 규모별로는 소규모와 중규모 대규모로 구분할 수 있는 기준을 제시하였고, 반류수 제어의 경우 반류수를 관리할 수 있는 수질 및 유량 센서의 위치를 제시하였다. 연계처리수 제어의 경우 연계처리수가 하수처리장에 미치는 영향과 제어 지점을 제시하였으며, 약품주입량 제어의 경우 지능형 하수처리장 도입에 따라 약품 주입량을 최적화할 수 있는 시스템을 제시하였다. 동절기 운영의 경우 수온 저하에 따른 질산화 저하를 고려하였을 때 제어해야 하는 센서와 펌프를 제시하였다. 총 유기탄소 제어의 경우 향후 오염총량제를 고려한 연동 시스템을 제시하였다. 이러한 운전제어 시나리오들은 향후 지능형 하수처리 알고리즘과 시나리오에 사용될 기초자료로 활용될 수 있을 것으로 판단된다.

섬유질 섭취와 치질의 상관성에 관한 환자-대조군 연구 (A Case-Control Study on the Relationship of Fiber Intake and Hemorrhoids)

  • 이상선
    • Journal of Nutrition and Health
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    • 제27권1호
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    • pp.71-78
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    • 1994
  • Recently the incidence of hemorrhoids has been increased. There were various factors related to hemorrhoids, the amount of fiber intake was known as one of them. And so we performed this case-control study to investigate the association of hemorrhoids and fiber intake. The data was obtained by the combination of self-administered questionnaire and personal interview. The study population was consisted of matched 156 pairs, the cases were selected from S-hospital in Seoul, the age and sex matched control from the general population. The statistical analysis was performed by matched-analysis. The results summarized as follow : 1) As socio-economic status were low, the odds ratio of hemorrhoids were high. 2) There was significant association between hemorrhoids and regularity of eating time rather than regularity of defecation. 3) The odds ratio of hemorrhoids was 3 times higher in the presence of constipation. 4) The incidence of hemorrhoids was influenced by psychological characteristics such as somatization, obsessive-compulsive, depression, and anxiety. 5) Fiber intake was significantly lower in the cases compared to the controls. When the constipation was controlled, the fiber intake was still lower in the cases. These data provide additional evidence that the fiber intake was related to hemorrhoids.

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중풍 발생 위험인자에 대한 환자-대조군 연구 (The Case-Control Study on the Risk Factors of Stroke in Korean Adults)

  • 강경원;강병갑;차민호;고미미;박세욱;방옥선;조기호;김윤식;최선미
    • 한국한의학연구원논문집
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    • 제13권2호통권20호
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    • pp.65-69
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    • 2007
  • Background and Purpose : The purpose of this case-control study was to show the relationship between risk factors(past medical history, BMI, WHR, smoking, drinking), warning signs(dyscinesia, sightless, dysarthria, sensory disorder, numbness, blephalospasm, facial spasm, tension) and the incidence of stroke in korean adults. Methods : 455 stroke patients were enrolled as the case group and 180 non-stroke patients as control group from Oct. 2005 to Feb. 2006. Patients were hospitalized within 2 weeks after the onset of stroke. Obesity were defined as $BMI{\geq}25kg/m2$, $WHR{\geq}0.9$ in male and $WHR{\geq}0.8$ in female. Risk factors and warning signs were obtained from personal interview. The analysis of the data was done by chi-square test. Fisher's exact test and test-sample t-test. Results : The percentage of current smokers(or current drinkers) of case group is higher significantly than that of control group. The past medical history of risk factors were found to be transient ischemic attack(p=0.0698), facial palsy(p=0.4061), hypertension(p<0.0001), hyperlipidemia(p=0.1484), DM(p<0.0001), ischemic heart disease(p=0.0093), migraine(p=0.0014) and hypochondria(p=0.2370). $WHR{\geq}0.9$ in male had a 6.696 (3.711-12.082) odds ratio, $WHR{\geq}0.8$ in female had a 1.567 (0.659-3.726) odds ratio. $BMI{\geq}25kg/m2$ had a 2.017(1.263-3.222). The dyscinesia and sensory disorder of warning signs were found to be statistical difference between case and control group. Conclusions : According to the above results, it was found that smoking, drinking, BMI, WHR, hypertension, DM, ischemic heart disease, migraine affected to the incidence of stroke.

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동공크기변이도를 통한 침자극과 스트레스의 상관관계 연구 (A Study on the Relationship with Acupuncture Stimulation and Stress -Using Pupil Size Variability(PSV)-)

  • 최우진;허용석;박경모;김지은;이승기
    • 동의신경정신과학회지
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    • 제16권2호
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    • pp.113-124
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    • 2005
  • Objectives : The purpose of this case-control research was to investigate the effects of acupuncture stimulation on autonomic nervous system for patients with PSV and to find out relationship with anti-stress effects. Methods : The study group consists of 24 patients with self-recognition of stress as the case group, and 20 normal person as the control group by similar age. We measured PSV of case and control groups before acupuncture stimulation, prick acupuncture in Hegu(LI4), Taichong(Liv3), Shenme(H7), Neiguan(P6), Zusanli(S36). After treating for 20 minutes, measurement values of PSV were compared for pre-acupuncture and post-acupuncture Results : 1. Pupil size of the case group were decreased significantly after acupuncture stimulation in the 1st 2nd experiments. Pupil size of the control group was decreased significantly after acupuncture stimulation in the 1st experiment. 2. Pupil size of the case group were decreased significantly between the 1st and 2nd experiments before acupuncture stimulation. Conclusion : The results suggest that acupuncture stimulation is associated with changed activity in the sympathetic and parasympathetic nervous system. Measurement values of PSV is suitable to estimate the activity of automatic nervous system.

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편의점에서 판매되는 햄버거와 샌드위치의 유통과정중 품질관리에 관한 연구 (A Study on the Quality Control for the Circulation Steps including Productipn, Transportation, Selling about Hamburger & Sandwich in Convenience Store)

  • 김혜영;송용혜
    • 한국식생활문화학회지
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    • 제11권4호
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    • pp.465-473
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    • 1996
  • The purpose of this study was to evaluate microbiological hazards in the steps of production, transportation and selling of hamburger and sandwich that were marketed in CVS, then to identify methods of control. The reasults are as follows: As the reasult of operation surroundings of manufacturerand reserch of circulation, $4{\sim}6$ hours are needed from manufacturer to CVS. Also transportation car mean temperature was $10^{\circ}C$ which exceeds the standard of $7^{\circ}C$ or below. Hamburger: Critical control points identified were purchasing, cooking, post-preparation, transportation and holding at CVS. As the reasult of microbial analysis following the case of holding methods and reheating at CVS, microbes of cold holding and reheat after cold holding was within standard value. But in the case of room temperature microbes exceeded standard value. Sandwich: Critical control points identified were purchasing, cooking, post-preparation, transportation and holding at CVS. As the reasult of microbial analysis following the case of holding methods and reheating at CVS, total plate counts of cold holding and reheat after cold holding was within standard value. But in the case of room temperature holding after 24 hours total plate counts exceeded standard value. In the case of room temperature holding the number of microbes increased according to the passage of time. As a reasult of food poisoning bacteria, it was negative in every test in sample against V. parahaemolyticus, Salmonella, S. aureus.

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부모의 지지와 통제 및 학교생활 적응이 남녀 청소년의 자살생각에 미치는 영향: 우울의 매개효과를 중심으로 (The Effects of Parental Support, Control and School Life Adjustment on Suicidal Ideation of Adolescents: Mediating Effects of Depression)

  • 이아영;박부진;김세영
    • 아동학회지
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    • 제37권1호
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    • pp.61-71
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    • 2016
  • Objective: The purpose of this study was to confirm if there are gender differences in influences of parental support, control, and school life adjustment on suicidal ideation of adolescents and to examine the mediating effect of depression on the influences of independent variables on their suicidal ideation. Methods: This study comprised a total of 671 students in seventh and eighth grades in Seoul and Gyeonggi-do. The data were analyzed for frequency, average, and standard deviation, using the t-test, Pearson's correlation analysis, stepwise regression analysis, hierarchical multiple regression analysis, and the Sobel test. Results and Conclusion: First, significant differences among adolescents' gender were shown in fathers' psychological control, mothers' behavior control, and suicidal ideation. Second, in the case of male adolescents, all independent variables were found to have a full mediating effect on their suicidal ideation. Meanwhile, in the case of female adolescents, independent variables except for mothers' psychological control were found to have a full mediating effect on their suicidal ideation. Mothers' psychological control was found to have a partial mediating effect on suicidal ideation of adolescents for both genders.