• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.1
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• pp.52-58
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• 2005

Among various modern control theories, PID control has been well used for several decades. PID algorithms need some tuning methods which are used for selecting PID parameters. But in some cases various kinds of performance indices are used instead of well-known tuning rules, and so variable type of performance index must be tested so that controllers, output characteristics and disturbance rejection property meet some specifications. In this paper, linear conbinational type of performance index using error signal, time, control input and robustness is used to the PID control of air conditioning system. By use of the 2 DOF PID parmeters minimizing perfromacne index controllers, output characteristics and robustness properties are analyzed. Simulations are done by use of MATLAB with Simulink.

• The Korean Journal of Nuclear Medicine
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• v.17 no.2
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• pp.19-24
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• 1983

The purpose of this study was to develop a method by which the sensitivity of radionuclide liver imaging for detection of liver cirrhosis could be enhanced. Dynamic blood flow scan were performed 21 cases of liver cirrhosis patients by using computerized gamma camera named arterialization index. The results were as follows: 1) Arterialization index were higher in liver cirrhosis comparing to normal value 0.33 and its mean is 2. 02. 2) Comparing to static liver scan, higher sensitivity in dynamic hepatic blood flow scan for detection of liver cirrhosis. Sensitivity for detection of liver cirrhosis is over 90%. 3) There are no correlation between arterialization index and serum albumin level. The use of hepatic dynamic blood flow scan proved effective in detection of liver cirrhosis. However, the test may be used as an aid in distinguishing between normal and pathologic livers.

• Journal of Power Electronics
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• v.16 no.1
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• pp.319-328
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• 2016

In this study, we first briefly introduce the effect of circulating current control on the modulation signal of a modular multilevel converter (MMC). The maximum modulation index is also theoretically derived. According to the optimal modulation index analysis and the model in the continuous domain, different DC-side output impedance equivalent models of MMC with/without compensating component are derived. The DC-side impedance of MMC inverter station can be regarded as a series xR + yL + zC branch in both cases. The compensating component of the maximum modulation index is also related to the DC equivalent impedance with circulating current control. The frequency characteristic of impedance for MMC, which is observed from its DC side, is analyzed. Finally, this study investigates the prediction of the DC voltage ripple transfer between two-terminal MMC high-voltage direct current systems under unbalanced conditions. The rationality and accuracy of the impedance model are verified through MATLAB/Simulink simulations and experimental results.

• Journal of Korean Medicine for Obesity Research
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• v.6 no.1
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• pp.69-80
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• 2006

Object : Waist circumference(WC), waist-hip ratio(WHR), waist-stature ratio(WSR), and body mass index(BMI) are commonly used for evaluating obesity. This Research were done to determine what is more sensitive obesity indexes(WC, WHR, WSR, BMI) Correlated with body composition such as body fat mass, body fat(%), visceral fat area, and fat free mass. And what is more sensitively correlated obesity indexes with % changes of body composition during weight reduction treatment. Methods : This clinical retrospective research were carried out 127 cases of female obese outpatients with weight reduction treatment during 1 month. Bioelectrical impedence analysis(for body composition) and body size(for anthropometric obesity indexes) were estimated in pre-treatment and post-treatment to evaluate the obesity indexes. Pearson correlation coefficients were used to select useful obesity index. Result & Conclusion : BMI is useful index for diagnosis and evaluation of obesity. WSR is sensitively correlated with visceral fat area and body fat(%). So, WSR is useful index for evaluating abdominal obesity and risk factors of metabolic syndrome. WC is correlated with both body fat mass and fat free mass. WHR is not optimal for diagnosis and evaluation of obesity.

• Structural Engineering and Mechanics
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• v.77 no.2
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• pp.151-165
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• 2021

This paper aims to present a novelty damage detection method to identify damage locations by the simultaneous use of both the energy and displacement damage indices. Using this novelty method, the damaged location and even the damaged floor are accurately detected. As a first method, a combination of the instantaneous frequency energy index (EDI) and the structural acceleration responses are used. To evaluate the first method and also present a rapid assessment method, the Displacement Damage Index (DDI), which consists of the error reliability (β) and Normal Probability Density Function (NPDF) indices, are introduced. The innovation of this method is the simultaneous use of displacement-acceleration responses during one process, which is more effective in the rapid evaluation of damage patterns with velocity vectors. In order to evaluate the effectiveness of the proposed method, various damage scenarios of the ASCE benchmark problem, and the effects of measurement noise were studied numerically. Extensive analyses show that the rapid proposed method is capable of accurately detecting the location of sparse damages through the building. Finally, the proposed method was validated by experimental studies of a six-story steel building structure with single and multiple damage cases.

• Journal of information and communication convergence engineering
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• v.20 no.3
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• pp.181-188
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• 2022

An intelligent distributed multi-agent system (IDMS) using reinforcement learning (RL) is a challenging and intricate problem in which single or multiple agent(s) aim to achieve their specific goals (sub-goal and final goal), where they move their states in a complex and cluttered environment. The environment provided by the IDMS provides a cumulative optimal reward for each action based on the policy of the learning process. Most actions involve interacting with a given IDMS environment; therefore, it can provide the following elements: a starting agent state, multiple obstacles, agent goals, and a cluttered index. The reward in the environment is also reflected by RL-based agents, in which agents can move randomly or intelligently to reach their respective goals, to improve the agent learning performance. We extend different cases of intelligent multi-agent systems from our previous works: (a) a proposed environment-clutter-based-index for agent sub-goal selection and analysis of its effect, and (b) a newly proposed RL reward scheme based on the environmental clutter-index to identify and analyze the prerequisites and conditions for improving the overall system.

• Korean Journal of Construction Engineering and Management
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• v.7 no.5
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• pp.77-84
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• 2006

Indexes have played an important role as a economic indicator or performance indicator in many industries for a long time. In construction industry, indexes, or Construction Cost Index(CCI), have been used to compensate for the gap of time in Estimate Using the Historical Cost Data from Feb. 2004. CCI is composed of index formula and resources. Existing literatures had used Laspyeres Index as a index formula. And, Leontief table, the bills of quantities, and information of price surveyor were used as a resource. When applying Laspyeres formula and the resources to calculating the CCI, the problems such as double application of price fluctuation, calculating the incorrect weights, may be generated. This paper analyzed the existing economic relevant indexes as well as Laspyeres formula. Thus, feasibility of them was analyzed using three practical cases of apartments. And then, Quantity based Base Period Price Index(QBPPI) was developed to consider the characteristics of construction more accurately.

• The Korean Journal of Cytopathology
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• v.13 no.1
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• pp.21-27
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• 2002

Papillary immature metaplasia (PIM) of the uterine cervix (Immature condyloma) is a subset of low grade squamous intraepithelial lesion (LSIL) which is frequently associated with human papilloma virus (HPV) types 6 and 11. The histologic features of PIM include filiform papillae lined by evenly spaced immature metaplastic-type cells with frequent nucleoli, mild anisokaryosis, and a low mitotic index. To characterize the cytologic changes associated with PIM, we analyzed 14 cases of PIM from our file. We reviewed biopsy slides and the cervicovaginal smears taken proximate to the time of blopsy. Histologically, nine cases had either flat condyloma (7 cases) or high grade squamous intraepithelial lesion (HSIL) (2 cases). Cytologic changes included cells in various stages of maturation with karyomegaly (14 cases), cells with irregularities in the nuclear membrane (13 cases), intermediate cells with karyomegaly(13 cases), cells with binucleatlon (13 cases), and aborted koliocytes (11 cases) Cervicovaginal smears from all cases were interpreted as atypical squamous cells of undetermined significance (ASCUS), NOS or ASCUS, rule out squamous intraepithelial lesion (SIL) or LSIL in two cases with flat condyloma or HSIL in a case with severe dysplasia. PIM is a distinct histologic entity that can present with a spectrum of cytologic findings, but cytologic findings may resemble variable reactive conditions and immature HSIL. Therefore, it is difficult to diagnose PIM by cytology alone. However, the meticulous efforts for making the cytologic diagnoses which can Induce active management of patients are recommended because PIM is a variant of LSIL and frequently has a flat condyloma or HSIL.

• Journal of Preventive Medicine and Public Health
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• v.36 no.1
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• pp.77-84
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• 2003

Objectives : Two related cases of Hemolytic-Uremic Syndrome (HUS) were reported to the Korea National Institute of Health in May, 2001. Shiga toxin 2 genes were detected in both stool samples. We suspected an enterohemorrhagic Escherichia coli (EHEC) infection as the cause of the HUS, and conducted an investigation to find the source of the infection and its route of transmission. Methods : We peformed case investigations on these two related HUS cases, and obtained interviews and rectal swabs form the family members and other close contacts. Additionally, we peformed rectal swabs on the cattle raised by the household of the index patient. Results : We found a 20 month old index patient and a 6 year-old cousin had developed HUS, where there had been a 2 day history of contact with the index, and bacteriological examinations for these two patients revealed, indistinguishably, the same E. coli O171. The grandmother of the index patient was found to be asymptomatic, but E. coli O26 was isolated. We also found a probable case in the mother of the cousin. She reported a history of contact with the index, and developed bloody diarrhea of 3 days duration. The test results for the cattle revealed E. coli O26 in one cow, and E. coli O26 and O55 in another. E. coli O26, which was isolated in both cows and the grandmother of the index, were indistinguishably the same. Conclusions : We found that the E. coli O26 in the grandmother had originated from the cows, and that the E. coli O171 found in the index patient had been transmitted to the cousin through person-to-person contact.

• The Journal of Korean Obstetrics and Gynecology
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• v.26 no.1
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• pp.121-134
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• 2013

Objectives: The purpose of this study is to evaluate the effects of Shihogayonggolmoryo-tang on climacteric symptoms. Methods: We studied 5 climacteric symptoms patients who visited Oriental Hospital of OO University from March 2012 to September 2012. We treated them with Shihogayonggolmoryo-tang, acupuncture and moxibustion. The patients of climacteric symptoms had been estimated with Kupperman's index. Results: After treatment, climacteric symptoms were improved and mean score of Kupperman's index was reduced(the first case reduce from 82 to 13 during 3 months, the second case reduce from 81 to 19 during 2 months, the third case reduce from 80 to 21 during 2 months, the fouth case reduce from 50 to 9 during 2 months, the fifth case reduce from 66 to 17 during 1 month). Conclusions: This study suggests that Shihogayonggolmoryo-tang is significantly effective on climacteric symptoms patients.