• Coupled systems mechanics
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• 제13권2호
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• pp.153-170
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• 2024

The problem considered in this theoretical paper is the delamination of a multilayered inhomogeneous beam structure that has viscoelastic behaviour under angle of twist, horizontal and vertical displacements which vary smoothly with time according to prescribed laws. The cross-section of the beam is a rectangle. The layers are made of different materials which are smoothly inhomogeneous along the length of the beam. The beam under consideration represents statically undetermined structure since it is clamped in its two ends. The problem of the strain energy release rate is solved. For this purpose, the strain energy stored in the beam structure is analyzed. In order to verify the solution obtained, the strain energy release rate is found also analyzing the time-dependent compliances of the beam under prescribed angle of twist and displacements. A parametric investigation is carried-out by applying the solution obtained. Special attention is paid to the effect of the parameters which control the variation of the angle of twist and the displacements with time on the strain energy release rate.

• 한국환경생태학회지
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• 제23권4호
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• pp.317-325
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• 2009

시화호 초지대의 소각에 의한 조류의 서식 영향에 대한 연구는 2007년 3월에서 10월까지 경기도 화성시 마도면 송정리 인근 시화호간척지의 초지에서 실시하였다. 계획소각은 2007년 2월 28일에서 3월 1일까지 시화호 간척지의 초지 중 육상부에 인접한 지역에 대해 실시하였다. 소각지역에서는 총 30종 최대개체수 합계 181개체의 조류가 관찰되었으며, 존치지역에서는 24종 최대개체수 합계 154개체가 관찰되어 소각지역의 관찰조류 종수와 개체수가 높았다. 하지만 우점종은 소각지와 존치지간에 차이가 없었다. 수조류와 산림성조류를 제외한 소각지와 존치지의 평균 종수, 평균개체수, 종 다양도, 종 풍부도는 차이가 없었다. 초기의 군집특성은 계획소각에 의하여 변화하였지만, 후기에는 차이가 감소하였다. 계획소각에 의한 서식지 교란은 일시적으로 새로운 서식지 및 취식장소를 제공하였다. 계획소각이 목본식물의 유입을 차단하여 초지생태계를 유지하는 효과적인 방법이며, 주기적인 계획소각이 초지생태계를 유지 및 관리하는 효율적인 방안임을 제안하고자 한다.

• 제어로봇시스템학회논문지
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• 제22권5호
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• pp.320-325
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• 2016

This paper presents a robust finite-time sliding mode control (SMC) scheme for unknown disturbance and unmodeled nonlinear friction and dynamics in the robotic manipulator. A finite-time SMC (FSMC) surface and finite-time sliding mode controller are constructed to obtain faster error convergence than the conventional infinite-time based SMC. By adding prescribed constraint control term to a finite-time SMC to compensate for unknown disturbance and uncertainties, a robust control scheme can be designed as well as faster convergence control. In addition, simpler controller structure is built by using feed-forwarding upper bound coefficients of each manipulator dynamic parameters instead of model-based control or adaptive observer to estimate unknown manipulator parameters. Simulation and experimental evaluations highlight the efficacy of the proposed control scheme for an articulated robotic manipulator.

• 한국식품조리과학회지
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• 제12권4호
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• pp.562-570
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• 1996

A weight control program has been prescribed to investigate its effects on weight reduction of obese adults. The prescribed weight control program has been followed by 4 overweight adults and fad diets has been followed by 6 ovenveight adults for 3 to 7 months. The prescribed weight control program was basically the low calorie diet (1,500-1,800 kcal per day) and nutrition education was applied to enhance its effects. Fad diets were chosen among the fashionable diets and they were "apple diet" , "yogurt diet" and "Lee Hijae diet" Anthropometric measurements, biochemical parameters, and percent of body fat were measured after the respective period of weight control program. Body weight was significantly (p<0.01) reduced and the rate of obesity was also significantly lowered with the prescribed weight control program while the body weight and rate of obesity were not changed with the fad diets. Weight loss from the prescribed weight control program also led to the change of total cholesterol levels while LDL-cholesterol, HDL-cholesterol, triglyceride were not significantly changed. Nutrition education and counseling of the weight control subjects induced more weight loss and better food behavior. It is suggested that a weight loss program should be based on the low calorie diet with the well-planned nutrition education The fashionable diets were attractive for a short time period in weight reduction but the rapid weight gain was noticed right after the diets ceased.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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• pp.86-89
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• 1986

This paper presents a design methodology for a PID regulator. The parameters of the PID regulator are determined through equivalent structure to the closed-loop system whose feedback gain assigns prescribed eigenvalues of the closed-loop system and minimizes a given performance index.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제16권2호
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• pp.140-146
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• 2016

This paper proposes a control method of the Segway with unknown control coefficient and input saturation. To design a simple controller for the Segway with the model uncertainty, the prescribed performance function is used. Furthermore, an auxiliary variable is introduced to deal with unknown time-varying control coefficient and input saturation problem. Due to the auxiliary variable, function approximators are not used in this paper although all model uncertainties are unknown. Thus, the controller can be simple. From the Lyapunov stability theory, it is proved that all errors of the proposed control system remain within the prescribed performance bounds. Finally, the simulation results are presented to demonstrate the performance of the proposed scheme.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.6055-6059
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• 2015

Background: Medication policy development in Thailand is continually promoting rational drug use. Letrozole, an endocrine therapy drug, is usually prescribed for post-menopausal status early and advanced stage breast cancer. After Ministry of Public Health announced Letrozole as compulsory licensed drug in 2009, more breast cancer patients can access to this drug at low cost especially those within universal coverage schemes. To ensure that Letrozole is rationally prescribed, the drug utilization study was conducted. Objectives: The aim of this study was to describe the appropriate use of Letrozole in breast cancer and the relationship between appropriate use and health benefit schemes. Materials and Methods: A retrospective study to evaluate use of Letrozole in breast cancer patients was performed for six months between January - June 2010 in seven regional cancer hospitals, Thailand. All prescriptions of Letrozole were identified from pharmacy dispensing databases and prescription papers. A medical record review was also performed to evaluate appropriate use referring to the drug use evaluation criteria. The approved criterion of this study was referred from the guideline of Thai National Formulary version 2010. Results: There were 681 prescriptions of Letrozole for 254 breast cancer patients with an average age of $58.6{\pm}10.0years$. The patients in universal coverage scheme (UCS), civil servant medication benefit scheme (CSMBS) and social security scheme (SSS) were 77.7%, 18.5% and 8.7% respectively. 10.6% were prescribed Letrozole for the first time. Letrozole were prescribed by oncologists (82.8%). The average number of tablets per prescription was $58{\pm}10$. Calcium supplements were prescribed concomitant with Letrozole for 19.4%. To assess drug use evaluation criteria, 45 prescriptions were excluded because of uncompleted clinical data, 636 prescriptions were evaluated. The study showed 86 prescriptions (13.5%) with inappropriate use including 6 (0.9%) not prescribed for estrogen receptor (ER) and/or progesterone receptor (PR) positive, 31 (4.9%) not prescribed for post-menopausal and 49 (7.7%) not prescribed for an appropriate duration. Appropriate use percentages in different health benefit schemes were similar, 85.7% of CSMBS, 86.4% of SSS and 86.7% of UCS. The relationship between health benefit scheme and appropriate use of Letrozole was not significantly different, ${\chi}^2$ (2, N = 636) = 0.081, p > 0.05. Conclusions: The study showed inappropriate use in breast cancer patients because of non-compliance with duration, menopausal status and hormone receptor requirements. To prescribe appropriate indication did not referred to the appropriate practice along the treatment. Drug use evaluation proved very useful for detecting the sign of inappropriate use and allows immediate feedback to the stakeholder for developing medication policy in the future. Importantly, there was no significantly difference in appropriate use of Letrozole across health benefit schemes.

• 대한치과교정학회지
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• 제46권1호
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• pp.36-41
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• 2016

Objective: The aim of this study was to evaluate retention practices commonly employed by orthodontists. The objectives were to identify the types of retainer frequently used and to investigate the variations in retention practice. Methods: A total of 97 orthodontists were randomly selected, and a questionnaire consisting of 25 multiple-choice questions sent to them by mail. Upon receiving of the completed questionnaires, the data were statistically analyzed. Results: A total of 32 responses were received; among these, 59.4% of orthodontists' practiced is in a government setting and 40.6% were in private practice. A vacuum-formed retainer was the most commonly used removable retainer for both maxillary (46.9%) and mandibular (46.9%) arches, followed by a Hawley retainer (maxilla, 43.8%; mandible, 37.5%), and a fixed retainer (maxilla, 3.1%; mandible, 9.4%). Of the responding orthodontists, 78.1% prescribed full-time wear (more than 20 h per day) for a duration of 3-9 months for a maxillary arch, compared to 71.9% for the mandibular arch. Only 18.8% of the orthodontists prescribed part-time wear of the retainer for the maxillary arch, compared to 21.9% for the mandibular arch. The majority of orthodontists did not instruct their patients to stop wearing removable retainers (71.9%) or fixed retainers (66.8%) at any specific time and they preferred their patients to continue wearing retainers. Conclusions: Vacuum-formed retainers are the most commonly used retainers among orthodontists. The majority of orthodontists prescribed full-time wear for more than 20 h per day with a duration of 3-9 months and preferred indefinite use of the retainer.

• 한국임상약학회지
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• 제26권3호
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• pp.213-219
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• 2016

Objective: Although guideline recommends beta blockers (BBs) as first line antianginal agent and calcium channel blockers (CCBs) as alternatives after percutaneous coronary intervention (PCI), the prescription patterns in real practice are not in accordance with the guideline. We aimed to investigate the prescribing patterns of primary antianginal drug and relating factors in patients who underwent PCI. Methods: Patients who have undergone PCI without myocardial infarction (MI) from November 2012 to June 2014 and followed up at least one year in a tertiary teaching hospital were included. Prescribing patterns of primary antianginal drug before, at the time of, and one year after PCI were described. Factors affecting drug selection, and their relationship with incidence of clinical outcomes defined as MI and repeated PCI, unscheduled admission or visit related with heart problem were analyzed with multivariate logistic regression. Results: A total of 506 patients were included and as primary antianginal drugs, BB, CCB, and both were prescribed in 32.2%, 24.5%, and 17.8% of patients, respectively. Also, neither BB nor CCB was prescribed at the time of PCI in 25.5% of patients. Compared with BB, CCBs were more likely prescribed in patients who had hypertension (Odds Ratio, OR 2.18, 95% confidence interval, CI 1.16-4.07), use of same class before PCI (OR 7.18, 3.37-15.2) and concomitant angiotensin receptor blocker (ARB) use (OR, 1.92, 95% CI 1.10-3.33). Incidence of clinical outcomes were not significantly greater in patients who prescribed CCB compared with BB at the time of PCI (aOR 1.32, CI 0.65-2.68). Conclusion: This study demonstrated that half of the patients who underwent PCI were prescribed BB. CCB were favored in patients with hypertension, use of same class before PCI, and concomitant ARB use. Significant difference in clinical outcome was not observed between BB and CCB selection as primary antianginal drug.

• 대한산업공학회지
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• 제19권4호
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• pp.105-114
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• 1993

In this article, a planar geodesic (2-dimensional minimum length curve between two points) on which the maximum curvature is constrained and with prescribed initial and terminal directions is studied. A generic problem is formulated by the minimum-time optimal control problem in free terminal time. It is shown that the optimal path ($G^2$) may contain a singular arc or not and that the general types of $G^2$ can he classified into the 3 classes of control sequences. Finally, the explicit form of $G^2$ is derived geometrically as well as algebraically form the main theorem of this article.