• Journal of Electrical Engineering and Technology
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• v.3 no.1
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• pp.52-59
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• 2008

This paper describes the secant method for solving the economic dispatch (ED) problem with generator constraints and transmission losses. The ED problem is an important optimization problem in the economic operation of a power system. The proposed algorithm involves selection of minimum and maximum incremental costs (lambda values) and then the evaluation of optimal lambda at required power demand is done by secant method. The proposed algorithm has been tested on a power system having 6, 15, and 40 generating units. Studies have been made on the proposed method to solve the ED problem by taking 120 and 200 units with generator constraints. Simulation results of the proposed approach were compared in terms of solution quality, convergence characteristics, and computation efficiency with conventional methods such as lambda iterative method, heuristic methods such as genetic algorithm, and meta-heuristic methods like particle swarm optimization. It is observed from different case studies that the proposed method provides qualitative solutions with less computational time compared to various methods available in the literature.

• Journal of Electrical Engineering and Technology
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• v.8 no.1
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• pp.80-89
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• 2013

This paper presents an efficient approach for solving economic dispatch (ED) problems with nonconvex cost functions using a 'Mean-Variance Optimization (MVO)' algorithm with Kuhn-Tucker condition and swap process. The aim of the ED problem, one of the most important activities in power system operation and planning, is to determine the optimal combination of power outputs of all generating units so as to meet the required load demand at minimum operating cost while satisfying system equality and inequality constraints. This paper applies Kuhn-Tucker condition and swap process to a MVO algorithm to improve a global minimum searching capability. The proposed MVO is applied to three different nonconvex ED problems with valve-point effects, prohibited operating zones, transmission network losses, and multi-fuels with valve-point effects. Additionally, it is applied to the large-scale power system of Korea. The results are compared with those of the state-of-the-art methods as well.

• Journal of Korean Clinical Nursing Research
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• v.20 no.1
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• pp.75-89
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• 2014

Purpose: This study was done to identify conditions of cancer patients who visited an emergency department (ED) with the side effects of chemotherapy. Methods: Data were collected retrospectively from medical records of 294 cancer patients who visited a tertiary hospital in 2009 for treatment of side effects of chemotherapy. Records were reviewed for characteristics of participants and side effects of chemotherapy. Data were analyzed using SPSS software. Results: ED Triage grade 3 was 81.6%. The hospitalization ratio was 72.8%, and 6.5% died during the admission. Most frequent side effects were thrombocytopenia (80.6%), anemia (74.5%), pain (52.0%), neutropenia (50.7%), and leucopenia (46.3%). The hospitalization group showed more severe leucopenia than the discharge group (p=.020). Patients in the group who died had higher scores for dyspnea compared to patients discharged or hospitalized (p<.05). Conclusion: Results of the study suggest that there is a special need to develop a system to manage side effects of chemotherapy. Also it is necessary to provide appropriate care and treatment with prompt initial evaluation when cancer patients with side effects of chemotherapy present in the ED. More effective educational discharge programs should also be developed to help these patients cope with various side effects of chemotherapy.

• Archives of Pharmacal Research
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• v.19 no.3
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• pp.197-200
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• 1996

6-[(N-2,3-Dichlorophenyl)aminol-7-chloro-5,8-quinolinedione (RCK1 1) was tested for in vivo antifungal activities in the treatment of systemic infection with Canclicla albicans in normal mice compared with ketoconazole. The therapeutic potential of RCK11 had been assessed by evaluating their activities (survival rates) against systemic infections in normal mice. $ED_{50}$ of intraperitoneally administered RCK11 was $0.10\pm0.01 mg/kg$ but that of ketoconazole had $8.00\pm0.73 mg/kg$ respectively. When RCK11 was administered intravenously at the $ED_{50}$(0.10 mg/kg), the colony counts of Canoliola albicans in the liver after 7 days and 14 days were reduced as likely as ketoconazole at the $ED_{50}$ (8.00 mg/kg), and the better survival rates than ketoconazole were achieved after 14 days. The results suggest that RCK11 may be a potent antifungal agent.

• Applied Microscopy
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• v.44 no.4
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• pp.144-149
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• 2014

A strategy for phase identification of precipitates in high Al-containing austenitic and ferritic steels using electron diffraction (ED) is studied. Comparative studies of the various Al-containing precipitates (k-carbide, $Ni_3Al$, $Fe_3Al$, FeAl) show the similarities of crystal structure and lattice parameter. However, the slight differences of lattice parameter and structure display characteristic ED patterns (EDPs) which can be identified. $L1_2$ k-carbide and $Ni_3Al$ can be differentiated by the length of ${\rightarrow}_g$ (the reciprocal lattice vector), even though they show perfectly identical shapes of EDPs. $DO_3$ $Fe_3Al$ and $B_2$ FeAl show the characteristic EDs in [110] and [112] beam directions due to the differences of Fe site occupancies in unit cells. k-carbide, $Ni_3Al$, and FeAl show also the similar EDs in [112], [112], and [110] beam directions, respectively. All the possible similarities of EDs among each phases and the strategy for phase identification are discussed on the bases of kinematical ED simulation.

• Quality Improvement in Health Care
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• v.12 no.1
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• pp.114-123
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• 2006

Background : Patients who were discharged from the emergency department(ED) may revisit. These patients are divided into two groups; one is expected scheduled condition, the other is unexpected condition. These patients of inappropriate revisits to the ED would be unsatisfied, difficult to make rapport and take legal action as a result of additional medical charges. The purpose of this study was to reduce inappropriate revisits to the ED with a new method which was developed by analyzing inappropriate revisits in 2002. Methods : This study was conducted in a tertiary hospital consisting of 1,278 beds. The most common cause of inappropriate revisits was the medical team's lack of explanation about a disease. Thus we decided that the effective method was to offer full explanations to patients to understand the clinical pathway of a disease. We made four types of stickers to explain most common 4 diseases in 2003. An emergency physician completed 'discharge explanation report' and explained it to patients in 2004. Results : In 2002 inappropriate revisited patients were 164, patients with four diseases were 79. During the same period of 2003, inappropriate revisited patients were 56 (-65.9%), four disease patients were 6 (-92.4%) and in 2004 inappropriate revisited patients were 52, four disease patients were 19. Causes of revisits were lack of explanation about a disease in 35 patients (44.3%) in 2003, and 5 patients (83.3%) in 2003, and 16 patients (84.2%). Conclusions : Application of 'explanation stickers' at discharge reduced inappropriate revisits from 34.5% in 2002 to 15.9% in 2003. Application of 'Discharge explanation report' by emergency physician reduced inappropriate revisits from 15.9% in 2003 to 13.5% in 2004. Reduction of inappropriate revisits elevated the quality of medical treatment, and decreased patients' dissatisfaction in ED.

• International Journal of High-Rise Buildings
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• v.3 no.1
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• pp.21-33
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• 2014

The tied braced frame (TBF) system was developed to achieve uniform seismic inelastic demand along the height of multi-storey eccentrically braced steel frames. A modular tied braced frame (M-TBF) configuration has been recently proposed to reach the same objective while reducing the large axial force demand imposed on the vertical tie members connecting the link beams together in TBFs. M-TBFs may however experience variations in storey drifts at levels where the ties have been removed to form the modules. In this paper, the possibility of reducing the discontinuity in displacement response of a 16-storey M-TBF structure by introducing energy dissipating (ED) devices between the modules is examined. Two M-TBF configurations are investigated: an M-TBF with two 8-storey modules and an M-TBF with four 4-storey modules. Three types of ED devices are studied: friction dampers (FD), buckling restrained bracing (BRB) members and self-centering energy dissipative (SCED) members. The ED devices were sized such that no additional force demand was imposed on the discontinuous tie members. Nonlinear response history analysis showed that all three ED systems can be used to reduce discontinuities in storey drifts of M-TBFs. The BRB members experienced the smallest peak deformations whereas minimum residual deformations were obtained with the SCED devices.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.4
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• pp.479-486
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• 2016

A previous genome-wide association study (GWAS) exposed histone deacetylase 2 (HDAC2) as a possible candidate gene for breast muscle weight in chickens. The present research has examined the possible role of HDAC2 in skeletal muscle development in chickens. Gene expression was measured by quantitative polymerase chain reaction in breast and thigh muscles during both embryonic (four ages) and post-hatch (five ages) development and in cultures of primary myoblasts during both proliferation and differentiation. The expression of HDAC2 increased significantly across embryonic days (ED) in breast (ED 14, 16, 18, and 21) and thigh (ED 14 and 18, and ED 14 and 21) muscles suggesting that it possibly plays a role in myoblast hyperplasia in both breast and thigh muscles. Transcript abundance of HDAC2 identified significantly higher in fast growing muscle than slow growing in chickens at d 90 of age. Expression of HDAC2 during myoblast proliferation in vitro declined between 24 h and 48 h when expression of the marker gene paired box 7 (PAX7) increased and cell numbers increased throughout 72 h of culture. During induced differentiation of myoblasts to myotubes, the abundance of HDAC2 and the marker gene myogenic differentiation 1 (MYOD1), both increased significantly. Taken together, it is suggested that HDAC2 is most likely involved in a suppressive fashion in myoblast proliferation and may play a positive role in myoblast differentiation. The present results confirm the suggestion that HDAC2 is a functional gene for pre-hatch and post-hatch (fast growing muscle) development of chicken skeletal muscle.

• Journal of The Korean Society of Emergency Medicine
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• v.26 no.1
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• pp.29-37
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• 2015

Purpose: Stool exams are a useful tool for the early presumptive diagnosis of infectious bacterial diarrhea in the Emergency Department (ED). CT scans are often used to increase the physician's level of certainty and to facilitate patient triage by identifying the source of pain in most patients with an acute abdomen in the ED. This study was designed to investigate the correlation between stool exams and abdominal CT in patients with acute diarrhea visiting the ED. Methods: We conducted a retrospective study in the emergency department of a national university hospital from January 1, 2012 to June 30, 2013. The subjects consisted of 156 patients with acute diarrhea and abdominal pain who had stool exam results and abdominal CT findings. We divided the patients into three groups according to the stool exam results. Simultaneously, we evaluated their CT findings of the bowel and adjacent structures. Results: A total of 156 patients were enrolled. Frequency of abnormal CT findings showed statistically significant correlation with stool exams (p-value <0.001). Abnormal CT findings increased as WBCs and RBCs in stool increased (p-value <0.001). Conclusion: The stool exam was a statistically significant predictive variable in indirectly determining the severity of acute diarrhea and it showed correlation with the frequency of abnormal CT findings. It is suggested that stool exams can be used as a susceptible marker for predicting the probability of severe infectious colitis, and for making an early decision regarding close medical attention.

• Journal of The Korean Society of Clinical Toxicology
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• v.8 no.2
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• pp.69-78
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• 2010

Purpose: The living standards vary between the urban and rural areas in Korea. This study aims to compare the characteristics of acute poisoning victims in urban and rural areas. Methods: A retrospective study was conducted over a period of 2 years from 2008 to 2009. The study group included adults over 19 year old with acute poisoning and who were later were admitted to the local emergency medical center located in Daegu, Korea. The exclusion criteria were 1) the victims of adverse effects of therapeutic doses of drugs, 2) the victims with chronic exposure and 3) the victims who were missing data in their emergency medical records. We divided the victims into the adult group (19-64 years old) and the old group (over 65 years old). Results: There were 569 acute poisoning victims during the study period, and they constituted 1.11% of the total ED visits (51,199). Four hundred seventy six patients were enrolled in this study. Out of the 359 acute poisoning victims, 252 victims were from urban areas and 107 victims were from rural areas. They showed statistical differences for gender, ED access, transport, toxins and the time to the ED. In the old group, 61 victims out of 117 were from urban areas and the remaining 56 victims were from rural areas. They showed statistical differences for gender, ED access, toxins and transport. Conclusion: Through the clinical comparison between the acute poisoning victims of urban and rural areas, we exposed the clinical differences between the urban and rural areas, and we concluded that prevention and education for acute poisoning should be generated differently between the two groups.