• 한국정밀공학회지
• /
• 제18권7호
• /
• pp.53-64
• /
• 2001

The gain-scheduling control technique is vary useful in the control problem incorporating time varying parameters which can be measured in real time. Based on these facts, in this paper the sway control problem of the pendulum motion of a container hanging on the trolly, which transports containers from a container ship to trucks, is considered. In the container crane control problem, suppressing the residual swing motion of the container at the end of acceleration, deceleration or the case of that the unexpected disturbance input exists is main issue. For this problem, in general, the trolley motion control strategy is introduced and applied. But, in this paper, we introduce and synthesize a new type of swing motion control system. In this control system, a small auxiliary mass is installed on the spreader. And the actuator reacts against the auxiliary mass, applying inertial control forces to the container to reduce the swing motion in the desired manner. In this paper, we assume that an plant parameter is varying and apply the gain-scheduling control technique design the anti-swing motion control system for the controlled plant. In this control system, the controller dynamics are adjusted in real-time according to time-varying plant parameters. And the simulation result shows that the proposed control strategy is shown to be useful to the case of time-varying system and, robust to disturbances like winds and initial sway motion.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권9호
• /
• pp.4249-4253
• /
• 2012

While associations between trace elements and heavy metals with prostate cancer are still debatable, they have been considered as risk factors for prostate cancer. Thus, this study aimed to detect any links between selected minerals and heavy metals including Se, Zn, Cu, Mn and Fe with prostate cancer. A case control study was carried out among 100 subjects (case n=50, control n=50), matched for age and ethnicity. Trace elements and heavy metals level in hair and nail samples were determined by ICP-MS. Mean selenium levels in hair and nail of the cases were significantly lower as compared to controls. A similar trend was noted for zinc in both hair and nail samples, whereas the mean level of copper was significantly higher in cases than controls. Similar elevation was noted for iron and manganese (p<0.05 for all parameters). Low levels of selenium and zinc and high levels of copper, iron and manganese appear to be associated with the risk of prostate cancer. Further studies to elucidate the causal mechanisms and appropriate chemopreventive measures are needed.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권2호
• /
• pp.401-406
• /
• 2015

Background: This study was planned as comparative and descriptive in order to measure and evaluate the knowledge and attitudes regarding early diagnosis of women with and without a family history of cervical cancer. Materials and Methods: The study sample consisted of the relatives of female patients (N=253) who were admitted to Istanbul University of Medicine. Women with a family history of cervical cancer formed the case group, while those without family history of cervical cancer constituted the control group. Two distinct data collection tools, a questionnaire and the Miller Behavioral Style Scale (MBSS), were used in order to obtain data for evaluation with SPSS for Windows 20.0 statistics package program. Results: It was found that 61.0% of the case group with family history of cervical cancer and 19.0% of the control group without family history of cervical cancer were using early diagnostic methods. Thus the presence of an individual with cervical cancer in the family affected the attitudes towards early diagnosis. It was further found that the level of knowledge on cervical cancer and PAP smear test was higher in the case group, which was more sensitive with regard to being informed about cervical cancer as compared to general society. However, the average MBSS scores were not significantly different compared to the control group. Conclusions: It was noted that, women participating this study knowledgeable, but this did not necessarily transform into better behavior.

• 공학교육연구
• /
• 제20권1호
• /
• pp.63-68
• /
• 2017

This research is as a case study of innovative engineering education system through idea factory of korea maritime and ocean university and deals with development of temperature-humidity control device (THCD) for fiber storage on composites in viewpoint of problem solving method. Fiber reinforced plastic (FRP) includes many variables on the composite manufacturing process. Above all, the interfacial adhesion between the fiber and the matrix acts as an important thing that decided mechanical property of the FRP, and also it is profoundly linked to external temperature and relative humidity. High void fraction leads to a result in interlaminar fracture. Therefore, in this research, to establish correlation between fiber reinforcement and fiber storage conditions of temperature and relative humidity we developed a THCD for fiber reinforcement. To evaluate performance of the THCD, glass fiber reinforced plastic (GFRP) is made under the extreme conditions each temperature $34^{\circ}C$, relative humidity 98 % and it can be said that there are the change of mechanical properties according to fiber storage conditions. As a result, the THCD showed sufficient possible application for understanding and applied research of composites field in material engineering. Also, we could check that the necessity of introduction of innovative system such as idea factory existed.

• 한국간호교육학회지
• /
• 제17권1호
• /
• pp.25-35
• /
• 2011

Purpose: The purpose of this study was to evaluate the effects of an intravenous injection case-based clinical performance examination for improvement of problem-solving skill, nursing process application, nursing skill, and learning satisfaction. Method: This study's design was a randomized control group design. A total 93 students (experimental group, 49 control group, 44) who were junior nursing students in South Korea were included in this study. Data were collected from August 12th to 19th, 2010 and analyzed using SPSS 18.0. Result: The mean score of problem solving skills, intravenous injection skill, and learning satisfaction were significantly higher in the experimental group than the control group. However, the mean score of nursing process application was not significantly different between the two groups. Conclusion: These results indicate that the case-based clinical performance examination is effective for problem solving skill, nursing skill, and learning satisfaction. Therefore, it is recommended to adapt such teaching methods with integrated nursing practice education for various clinical skills development.

• 대한치과의사협회지
• /
• 제58권3호
• /
• pp.152-168
• /
• 2020

The propensity score matching method is a statistical method used to reduce selection bias in observational studies and to show effects similar to random allocation. There are many observational studies in dentistry research, and differences in baseline covariates between the control and case groups affect the outcome. In order to reduce the bias due to confounding variables, the propensity scores are used by equating groups based on the baseline covariates. This method is effective, especially when there are many covariates or the sample size is small. In this paper, the propensity score matching method was explained in a simple way with a dental example by using R software. This simulated data were obtained from one of retrospective study. The control group and the case group were matched according to the propensity score and compared before and after treatment. The propensity score matching method could be an alternative to compensate for the disadvantage of the observation study by reducing the bias based on the covariates with the propensity score.

• 한국물환경학회지
• /
• 제29권6호
• /
• pp.754-761
• /
• 2013

Urban floods are usually caused by the lack of drainage capacity. Hence, sewer capacity expansion methodology by replacing small pipes with bigger ones is primarily applied as a flood control measure. However, this approach is often unreasonable because of the costs and time involved. Thus, the installation of underground rainwater storage tanks with the two advantages of flood control and water conservation is proposed. This study compared the effectiveness of flood control by both the sewer expansion methodology and rainwater storage tanks using the Storm Water Management Model. Three cases were simulated in this study. The first case analyzed flood reduction by the storm sewer expansion methodology. The simulation results indicate that the overflow volume from manholes was reduced by 49% with this methodology. The second case analyzed flood reduction by installation of rainwater storage tanks. The simulation results indicate that the overflow volume was reduced by 62%. However, these two cases could not prevent urban floods completely. Hence, the third case analyzed the joint application of the storm sewer expansion methodology and rainwater storage tanks. In this simulation, flooding did not occur. Consequently, the results of this study clearly show that underground rainwater storage tanks are more effective for flood control than capacity expansion of storm sewer. Furthermore, the joint application of these two flood control measures is more effective than their separate application.

• Korean Journal of Acupuncture
• /
• 제28권4호
• /
• pp.147-158
• /
• 2011

Objectives : The purpose of this study was to obtain some knowledge about the acupuncture treatments on Parkinson's disease for the future practice and the research from the clinical studies in China. Methods : The literatures were searched using the data base-China Academic Journals (CAJ) (1994-2011). Clinical studies of acupuncture for Parkinson's disease such as randomized controlled trial (RCT), non-randomized controlled trial (NRCT), case series, case report were included. Results : Of 145 articles, 52 Clinical studies met our inclusion criteria: 20 RCTs, 7 NRCTs, 22 case series and 3 case reports. Various kinds of acupuncture treatments such as scalp acupuncture, body acupuncture, abdominal acupuncture, acupoint injection, eye acupuncture and thick needle acupuncture (粗鍼) were used in the clinical studies. The treatment and control groups take Madopa Tablet (Levodopa + Benserazide HCl) in the same time in many studies, and Madopa treatment was used as a comparative treatment in the most of studies. Acupuncture treatment was done daily or 2~3 times a week for 2~20 weeks. All of studies reported high effective rate in the treatment group compared to control group. Conclusions : The results of this study could be used for the future study about the acupuncture therapy for Parkinson's disease.

• 대한예방의학회:학술대회논문집
• /
• 대한예방의학회 1994년도 교수 연수회(역학)
• /
• pp.188-195
• /
• 1994

To an increasing extent, case-control studies are being undertaken to determine if use of early detection procedures is associated with reduced mortality from cancer. The authors recommend that in such studies the analysis focus on screening activity in cases that occurs during an interval prior to diagnosis in which the cancer is believed to be detectable and still curable and to a corresponding time period in controls. This approach places a heavy burden on the investigator to estimate accurately the period during which the tumor ought to be detectable using the test in question and to sort out reliably tests done in response to signs or symptoms of the cancer from screening tests per se. Nonetheless, the authors feel that it offers the greatest ability to discern a true benefit of screening, while minimizing the numerous potential biases that can be present in this type of study.

• 제어로봇시스템학회논문지
• /
• 제7권7호
• /
• pp.559-566
• /
• 2001

The sway control problem of the pendulum motion of a container hanging on the trolly, which transports containers from a container ship to trucks, is considered in the paper. In the container crane control problem, suppressing the residual swing motion of the container at the end of acceleration, deceleration or the case of that the unexpected disturbance input exists is main issue. For this problem, in general, the trolley motion control strategy is introduced and applied. In this paper, we introduce and synthesize a new type of swing motion control system in which a small auxiliary mass is installed on the spreader. The actuator reacting against the auxiliary mall applies inertial control forces to the container to reduce the swing motion in the desired manner. In this paper, we apply the $H^{\infty}$ based gain-scheduling control technique to the anti-swing motion control system design problem of the controlled plant. In this control system, the controller dynamics are adjusted in real-time according to time-varying plant parameters. And the simulation result shows that the proposed control strategy is shown to be useful for the case of time-varying system and, robust to disturbances such as winds and initial sway motion.