• Journal of Korean Society of Transportation
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• v.17 no.2
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• pp.41-53
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• 1999

The rate of automobile ownerships has been increased significantly in multi-family housing sites so that government has made new parking regulations increasing the rate of parking supply by the high demand of parking lots in multi-family housing sites. However, the new regulation of parking supply has several problems that it applies to only new multi-family housing sites and disregards to the locational distinctions around the sites. It also has reduced to the open spaces in the sites and increased the price of housing units especially to the small size units of multi-family housing sites by increasing the number of underground parking lots. Furthermore, the residents have not been equal opportunity to access their parking lots even though they have been charged to equal amount of financial burden for the construction of underground parking lots. This research aims to relieve above problems by analysing parking supply and demand management strategies both domestic and foreign countries, and suggest to new parking management system for multi-family housing sites in 21st Centuries. This research reveals that most of multi-family housing sites want to be applied 1) diverse parking supply regulations considering the locational distinctions of sites, 2) parking lot ownership programs, 3) charging parking fees to second vehicles, 4) increasing parking lots both in the sites and around the sites, 5) enforcing police power to the parking violation vehicles to their sites. Especially, the multi-family housing sites consisting of small & medium size of units and locating in small & medium size of cites strongly want to be accepted new Parking regulations considered their locational and social distinctions and applied police power to the parking violation vehicles in their sites compared to the other multi-family housing sites.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3587-3593
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• 2009

Nowadays, the PV systems have been focused on the interconnection between the power source and the grid. The PV inverter, either single-phase or three-phase, can be considered as the core of the whole system because of an important role in the grid-interconnecting operation. An important issue in the inverter control is the load current regulation. In the literature, the Proportional+Integral (PI) controller, normally used in the current-controlled Voltage Source Inverter (VSI), cannot be a satisfactory controller for an ac system because of the steady-sate error and the poor disturbance rejection, especially in high-frequency range. By comparison with the PI controller, the Proportional+Resonant (PR) controller can introduce an infinite gain at the fundamental ac frequency; hence can achieve the zero steady-state error without requiring the complex transformation and the dq-coupling technique. In this paper, a PR controller is designed and adopted for replacing the PI controller. Based on the theoretical analyses, the PR controller based control strategy is implemented in a 32-bit fixed-point TMS320F2812 DSP and evaluated in a 3kW experimental prototype Photovoltaic (PV) power conditioning system (PCS). Simulation and experimental results are shown to verify the performance of implemented control scheme in PV PCS.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.817-825
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• 2017

The AC-common bus microgrid system can overcome several weaknesses of the DC microgrid system by interconnecting the DC/AC inverters used for renewable energy with an AC network. Nevertheless, the unbalanced loads inherent in the electric power systems of island and small communities can deteriorate the performance of the AC microgrid system. This is because of the limited voltage regulation capability and mixed power flow in the voltage source inverter. In order to overcome the unbalanced load condition, this paper proposes a voltage and current control algorithm for the 4-leg inverter based on the single phase d-q control method, as well as the modeling of the voltage controller using Matlab/Simulink S/W. From the S/W simulation and experiment of the 250KW proto-type inverter, it is confirmed that the proposed algorithm is a useful tool for the design and operation of the AC microgrid system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.8
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• pp.2968-2974
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• 2010

Nowadays, the PV systems have been focused on the grid connection between the power source and the grid. The PV inverter can be considered as the core of the whole system because of an important role in the grid-interfacing operation. An important issue in the inverter control is the load current regulation. In the literature, Proportional Integral (PI) controller, which is normally used in the current-controlled Voltage Source Inverter (VSI), cannot be a satisfactory controller for an AC system because of the steady-sate error and the poor disturbance rejection, especially in high-frequency range. Compared with conventional PI controller, Proportional Resonant (PR) controller can introduce an infinite gain at the fundamental frequency of the AC source; hence it can achieve the zero steady-state error without requiring the complex transformation and the de-coupling technique. Theoretical analyses of both PI and PR controller are presented and verified by simulation and experiment. Both controller are implemented in a 32-bit fixed-point TMS320F2812 DSP processor and evaluated on a 3kW experimental prototype PV Power Conditioning System (PCS). Simulation and experimental results are shown to verify the controller performances.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.12
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• pp.2221-2231
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• 2017

In this paper, we surveyed previous cases, network protocols (such as Wi-Fi, Zigbee, Z-wave, and WirelessHart) and propagation characteristics on the application of maintaining equipments for instrumentation and control (I&C) using wireless communication techniques inside the nuclear power plant (NPP). In addition, we compared and analyzed the difference of detailed regulations with respect to the electromagnetic interference (EMI) and radio frequency interference (RFI) in the Regulatory Guide 1.180 rev. 1 (RG. 1.180) for adopting the wireless communication techniques inside the NPP, and other regulations, such as MIL-STD 461E and IEC 61000-4, that are recognized in the KINS/RG-N03.09 (Rev. 2). Furthermore, we investigated evaluating factors about electromagnetic properties by considering indoor environments, wave scattering, shielding effectiveness, and the indoor wave attenuation model that were not included in the current electromagnetic compatibility regulation.

• Fire Science and Engineering
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• v.24 no.6
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• pp.61-68
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• 2010

In this paper, a research and development result for the implementation of single station fixed temperature detector for residential fire prevention is described. The detector was developed for the certification in Japanese market because of very low domestic market situation. It is in the situation that there is no other regulation especially for residential detectors in Korea, Japanese case has been reviewed. Investigation of domestic legal circumstances and a comparative study for the test standard owned by KFI (Korea Institute of Fire Industry & Technology) and JFEII (Japan Fire Equipment Inspection Institute) respectively are also indicated. The detector alarms with a buzzer and an indicating LED. In the implementation ultra low power MCU(Micro Controller Unit) is applied to control the sleeping state and the monitoring state properly with low current consumption. To sense the temperature fast response thermistor is adopted in the design of fixed temperature residential detector. Automatic test function and alarm stop function are also considered in the design. The major factors which influence to current consumption are explained for the purpose of design reference. Main electronics circuit parts related to it's characteristics of the detector are described. It is explained that the measured current and experimental result of the battery discharge can be met over 10 years operation.

• Journal of Preventive Medicine and Public Health
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• v.10 no.1
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• pp.94-101
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• 1977

Noise pollution, both in the environment and in the workplace, has been recognized as a major health hazard -one that can impair not only a person's hearing but also his physical and mental well-being. As industrialization progresses, the prevalence rate of occupational diseases is increasing, especially hearing loss, which has the highest prevalence rate among the occupational diseases. The major cause of noise is the construction of various large industries without any regulation of noise sources. Therefor, we must establish an enactment to control mechanical noise sources. as soon as possible. For the purpose of controlling the noise source, we must have exact data about such things as the sound level, the frequency of the peak sound and the revolutions per minute (r.p.m.) of the machine (a measure of the power of its motor). This study was undertaken in order to define the noise characteristics, the power of the machine's motor, the change of the sound level and the peak sound as the r.p.m. increases, and the permissible exposure time. The sample size of this study was 74 machines at 11 plants in 6 industries. The results are as follows; 1. The breakdown of the types of mechanical noise noted was : 63.6% continuous normal sound, 26.9% intermittent sound, 4.7% continuous repeating sound and 4.6% impulsive sound. 2. With respect to the type of industry, the overall sound level was the highest in the mechanical industry, with $103.8{\pm}2.8dB(A)$, and lowest in the textile industry, with $89.2{\pm}1.43dB(A)$. 3. With respect to the type of machine, the highest sound level was 124 dB(A) caused by Gauzing(II), in the mechanical industry, and the lowest was 76 dB(A) caused by Attachment (Jup Chack) (I) in the timber industry. 4. The shortest permissible exposure time to Gauzing(II) in the mechanical industry was less than 15 minutes. 5. Among 74 machines, 68.2% of the peak sound was situated in the high frequency range (52.7% at 2 KHz, 4.1% at 4 KHz and 1.4% at 8 KHz). 41.8% of the peak sound was in the middle frequency range (4.1% at 250Hz, 14.8% at 500Hz and 22.9% at 1KHz). 6. If one machine had two motors or more, the peak sound was shifted to the low frequency range. 7. As the r.p.m. increased, the overall and peak sound levels were increased without any change of the frequency of the peak sound. 8. Whenever the machines had the same kind and the same r.p.m., the overall and peak sounds were changed by the physicochemical characteristics of the raw materials and the management.

• Korean Security Journal
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• no.58
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• pp.59-80
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• 2019

Recently, our company has entered the modern knowledge company, government policy and regulation has a big influence on people's lives. Also, unlike in the past, I am hoping for administrative intervention as a problem peculiar to the environment, such as environmental housing problems, urban transportation problems, misuse problems, etc. and corporate pending issues. In this study, through the 10th year of the Seoul Special Citizen Judicial Police Force, if the local autonomy is a special envoy, it will try to present the correctness in the organization luck. As a measure to secure the nature of administrative action, the method of investigation was through the study of the execution process of administrative penalty and its result based on the statistical data of Seoul City. Therefore, we will analyze the process and operation of the 10-year organizational change of the Seoul Metropolitan Government's police force and examine how the police force of the people's livelihoods, which is a special investigation organization, is expanding its duties in order to strengthen the enforcement power of the administration. Also, we will make future-oriented suggestions to encourage the readjustment of the current relevant laws, such as the Ministry of Patriots and Veterans Affairs, and to actively accommodate the expected changes of the special law police organization in charge of the enforcement of the police system.

• KSBB Journal
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• v.27 no.5
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• pp.308-312
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• 2012

Argon-plasma jet (Ar-PJ) is generated by ionizing Ar gas, and the resulting Ar-PJ consists of a mixture of neutral particles, positive ions, negative electrons, and various reactive species. Although Ar-PJ has been used in various biomedical applications, little is known about the biological effects on cells located near the plasma-exposed region. Here, we investigated the effects of the Ar-PJ on actin cytoskeleton of mouse embryonic fibroblasts (MEFs) in response to indirect as well as direct exposure to Ar-PJ. This Ar-PJ was generated at 500 mL/min of flow rate and 100 V electric power by our device mainly consisting of electrodes, dielectrics, and a high-voltage power supply. Because actin cytoskeleton is the key cellular machinery involved in cellular movement and is implicated in regulation of cancer metastasis and thus resulting in a highly desirable cancer therapeutic target, we examined the actin filament architectures in Ar-PJ-treated MEFs by staining with an actin-specific phalloidin labeled with fluorescent dye. Interestingly, the Ar-PJ treatment causes destabilization of actin filament architectures in the regions indirectly exposed to Ar-PJ, but no differences in MEFs treated with Ar gas alone and in untreated cell control, indicating that this phenomenon is a specific cellular response against Ar-PJ in the live cells, which are indirectly exposed to Ar-PJ. Collectively, our study raises the possibility that Ar-PJ may have potential as anti-cancer drug effect through direct destabilization of the actin cytoskeleton.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.569-575
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• 2020

Recently, research on renewable energy technologies has come into the spotlight due to rising concerns over the depletion of fossil fuels and greenhouse gas emissions. Demand for portable electronic and wearable devices is increasing, and electronic devices are becoming smaller. Energy harvesting is a technology for overcoming limitations such as battery size and usage time. In this paper, the V-I characteristic curve and internal resistance of thermal electric devices were analyzed, and MPPT control methods were compared. The Perturbation and Observation (P&O) control method is economically inefficient because two sensors are required to measure the voltage and current of a Thermoelectric Generator(TEG). Therefore, this paper proposes a new MPPT control method that tracks MPP using only one sensor for the regulation of the output voltage. The proposed MPPT control method uses the relationship between the output voltage of the load and the duty ratio. Control is done by periodically sampling the output voltage of the DC-DC converter to increase or decrease the duty ratio to find the optimal duty ratio and maintain the MPP. A DC-DC converter was designed using a cascaded boost-buck converter, which has a two-switch topology. The proposed MPPT control method was verified by simulations using PSIM, and the results show that a voltage, current, and power of V=4.2 V, I=2.5 A, and P=10.5 W were obtained at the MPP from the V-I characteristic curve of the TEG.