• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.2
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• pp.97-105
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• 2008

This paper presents simulated and experimental test results of optimal control algorithm for an encapsulated ice thermal storage system with full capacity chiller operation. The algorithm finds an optimal combination of a chiller and/or a storage tank operation for the minimum total operation cost through a cycle of charging and discharging. Dynamic programming is used to find the optimal control schedule. The conventional control strategy of chiller-priority is the baseline case for comparing with the optimal control strategy through simulation and experimental test. Simulation shows that operating cost for the optimal control with chiller on-off operation is not so different from that with chiller part load capacity control. As a result from the experimental test, the optimal control operation according to the simulated operation schedule showed about 14 % of cost saving compared with the chiller-priority control.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.2
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• pp.67-74
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• 2018

Resource leveling minimizes resource fluctuations by deferring the earliest start times (ESTs) of non-critical activities within their corresponding total float. The intentional float-consumption for resource leveling purpose reduces the schedule delay contingency. This paper presents a method called Genetic Algorithm based Resource Leveling (GARL) that minimizes resource fluctuations and float-consumption impact over project duration. It identifies activities that are less sensitive to float-consumption and performs resource leveling using those activities. The study is of value to project scheduler because GARL identifies the set of activities to be deferred and the number of shift day(s) of each and every activities in the set within its total float expeditiously. It contributes to establish a baseline schedule which implements an optimal resource leveling plan. A case study is presented to verify the validity and usability of the method. It was confirmed that GARL satisfies the project duration constraint by considering resource fluctuations and float-consumption over project duration.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.352-358
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• 2013

As amount of information in construction industry is growing, the role of information system in project management is becoming increasingly important. With the emerging IT application to the advancing construction industry, construction project management system with advanced technology has been progressed vigorously to improve construction productivity and management efficiency. Recently, a web-based Project Management Information System (PMIS) is developed to support decision-making process by efficiently managing project related information generated from various discipline. Many firms are in the process of developing the PMIS system or already have been applied the system to various projects. However, PMIS is still in its early stage of development to be applied at industrial plant construction projects that process management is significantly emphasized for the successful execution of the project. With the complexity of the industrial plant projects, the industry practitioners need to be able to visualize the construction schedule information to manage the project efficiently. This study suggests methodologies for improving PMIS specialized for industrial plant piping construction projects to estimate the baseline schedule and performance measurement more accurately by developing a framework for the piping construction projects. By using this developed system, the researchers expect that piping construction projects will be more efficiently managed on a real-time basis through measuring progress of piping at each and every state of progress milestone and provide management with opportunities to forecast the level of efforts required to execute the remaining work scope in a timely manner

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.5
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• pp.231-239
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• 2014

This paper represents a method of existing building energy simulation using energy audit data. Energy audit must be carried out for reasonable analysis, because characteristics of existing buildings such as efficiency of fan, pump, flow rate, pressure, COP and operating schedule could be changed during the building operation. These building characteristics should be measured to estimate actual energy consumption of the existing building. In this study, we conducted energy audit and calculated energy savings for a 7-stories building as a case-study. The energy audit data were used to calibrate the building model of EnergyPlus simulation. Baseline model validated according to M&V guideline index. As a result, building characteristics are significant parameters making a big impact on energy savings in existing buildings.

• Korean Journal of Biological Psychiatry
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• v.3 no.1
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• pp.102-108
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• 1996

This was an open trial to evaluate the efficacy and safety of moclobemide twice daily for treatment of Korean patients with major depressive disorder(DSM-III-R). The duration of the trial was 6 weeks with the initial dose of moclobemide being fixed lor the first two weeks at 300mg/day(150mg twice daily, each token after morning and evening meals). Thereafter, when necessary, the dose was allowed to increase to 600mg/day or decrease to 150mg/day according to the seventy of the depression and/or the tolerability of the drug. Hypnotics and/or sedatives from a benzodiazepine group could be concomitantly administered at usual dosage. Patients were assessed at baseline and at days 14, 28 and 42. Efficacy was primarily judged on the Hamilton Rating Scale for Depression(HAM-D) and Beck Depression Inventory(BDI). Patients had to score at least 17 respectively an both scales to enter the trial. Secondary efficacy parameters included Clinical Global Impression(CGI) for severity of illness and improvement. Safety and tolerability were judged on reported adverse events, vital signs and laboratory parameters. In addition, there was a series of questions and assessments for the psychiatrists and patients to complete at the end of the trial Twenty nine patients completing trial were included in the analysis of efficacy : of thirty one patients participating in the safety and tolerability analysis, those who withdraw voluntarily without particular reasons or violated the treatment schedule were not included. The efficacies as determined by HAM-D, BDI or CGI were found to be significant compared to baseline. The number of responders defined as patients with a total score of 10 or less or with a total score of 50% or less of the baseline score on HAM-D and BDI were 17(59%) and 18(62%) respectively. Regarding safety and tolerability, nine patients(29%) reported mild adverse events probably related to moclobemide : of these one patient dropped out because of poor tolerability : however, there were no appreciable changes in blood pressure, pulse rate, body weight or laboratory parameters for all patients over the trial period. Furthermore, the physicians' and patients' opinions at final evaluation showed that moclabemide has a good antidepressant effect as well as a favorable tolerability. In conclusion, a twice-daily dosage schedule with maclobemide is recommendable for the treatment of Korean patients with major depressive disorder since its efficacy and safety were demonstrated in this study.

• Radiation Oncology Journal
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• v.35 no.1
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• pp.32-38
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• 2017

Purpose: Several accelerated partial breast radiation (APBR) techniques have been investigated in patients with early-stage breast cancer (BC); however, the optimal treatment delivery techniques remain unclear. We evaluated the feasibility and toxicity of APBR delivered using intensity-modulated radiation therapy (IMRT) in elderly patients with stage I BC, using a novel fractionation schedule. Materials and Methods: Forty-two patients aged ${\geq}65$ years, with stage I BC who underwent breast conserving surgery were enrolled in a phase I/II study evaluating APBR using IMRT. Forty eligible patients received 40 Gy in 4 Gy daily fractions. Patients were assessed for treatment related toxicities, and cosmesis, before APBR, during, and after completion of the treatment. Results: The median age was 73 years, median tumor size 0.8 cm and the median follow-up was 54 months. The 5-year locoregional control was 97.5% and overall survival 90%. Erythema and skin pigmentation was the most common acute adverse event, reported by 27 patients (69%). Twenty-six patients (65%) reported mild pain, rated 1-4/10. This improved at last follow-up to only 2 (15%). Overall the patient and physician reported worst late toxicities were lower than the baseline and at last follow-up, patients and physicians rated cosmesis as excellent/good in 93% and 86 %, respectively. Conclusion: In this prospective trial, we observed an excellent rate of tumor control with daily APBR. The acceptable toxicity profile and cosmetic results of this study support the use of IMRT planned APBR with daily schedule in elderly patients with early stage BC.

• Radiation Oncology Journal
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• v.35 no.4
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• pp.325-331
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• 2017

Purpose: There is controversy regarding the cosmetic outcome after accelerated partial breast radiation (APBR). We report the cosmetic outcome from a single-arm prospective clinical trial of APBR delivered using intensity-modulated radiation therapy (IMRT) in elderly patients with stage I breast cancer (BC), using a novel fractionation schedule. Materials and Methods: Forty-two patients aged ${\geq}65$, with Stage I BC who underwent breast-conserving surgery were enrolled in a phase I/II study evaluating a 2-week course of APBR. Thirty eligible patients received 40 Gy in 4 Gy daily fractions. Cosmetic outcome was assessed subjectively by physician/patient and objectively by using a computer program (BCCT.core) before APBR, during, and after completion of the treatment. Results: The median age was 72 years, the median tumor size was 0.8 cm, and the median follow-up was 50.5 months. The 5-year locoregional control in this cohort was 97% and overall survival 87%. At the last follow-up, patients and physicians rated cosmesis as 'excellent' or 'good' in 100% and 91 %, respectively. The BCCT.core program scored the cosmesis as 'excellent' or 'good' in 87% of the patients at baseline and 81% at the last follow-up. The median $V_{50}$ (20 Gy) of the whole breast volume (WBV) was 37.2%, with the median WBV $V_{100}$ (40 Gy) of 10.9%. Conclusion: An excellent rate of tumor control was observed in this prospective trial. By using multiple assessment techniques, we are showing acceptable cosmesis, supporting the use of IMRT planned APBR with daily schedule in elderly patients with early stage BC.

• Journal of Communications and Networks
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• v.14 no.6
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• pp.672-681
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• 2012

A potential breakthrough of the electrification of the vehicle fleet will incur a steep rise in the load on the electrical power grid. To avoid huge grid investments, coordinated charging of those vehicles is a must. In this paper, we assess algorithms to schedule charging of plug-in (hybrid) electric vehicles as to minimize the additional peak load they might cause. We first introduce two approaches, one based on a classical optimization approach using quadratic programming, and a second one, market based coordination, which is a multi-agent system that uses bidding on a virtual market to reach an equilibrium price that matches demand and supply. We benchmark these two methods against each other, as well as to a baseline scenario of uncontrolled charging. Our simulation results covering a residential area with 63 households show that controlled charging reduces peak load, load variability, and deviations from the nominal grid voltage.

• Industrial Engineering and Management Systems
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• v.11 no.1
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• pp.39-47
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• 2012

Requirements definition, which determines a project baseline, has a strong impact on the success of a project. However, since in-depth requirements are gradually revealed through the requirements definition process, the requirements definition is not a straight forward process and often falls into disorder. Thus project management standpoints are critical for the success of the requirements definition. In this paper, we present a framework and mechanisms of communication-centered project management, which controls the requirements definition process based on the situation of communication-oriented activities among stakeholders. In addition, we present a communication-centered project plan with a planning method. The project plan, which represents a time schedule of requirements definition activities, is made by a simulation-optimization algorithm using a stakeholder matrix showing the relations of requirements domains and relevant stakeholders. The effectiveness and the significance of communication-centered project management at the requirements definition phase are demonstrated by numerical examples.

• Korean Journal of Construction Engineering and Management
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• v.3 no.4 s.12
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• pp.114-122
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• 2002

Earned Value Management System(EVMS) is a management technique that is emerging as a valuable tool in the management of all projects, including and in particular construction projects. It is based on C/SCSC that has been released by the U.S. Department of Defense (DOD) in 1967. In a project that employs the earned value management concept, the project's measurable performance plans will be formed with the creation of CAPs. The formation of CAPs is a planning step necessary to form an earned value baseline. In this paper, a method is proposed to form CAPs using Material Requirement Planning(MRP) that is also known as a useful planning tool in the manufacturing industry. An application to a real project has been carried through workpackaging model.