• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.3
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• pp.12-25
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• 2020

The purpose of this study was to obtain information about the type of drones suitable for the management of entrants and entrants of islands in the marine national park. The research sites were 25 islands in the Hallyeohaesang National Park. The target islands were divided into three zones, and were investigated with different types of drones. The survey period was from October to November, 2019. As a result of the operation of drone airframe, drone with fixed wings was found to be favorable for the management of marine parks in medium and long distances compared to other types, but stopping flights for broadcasting was found to be unsuitable. Drone with rotational wings was found to be suitable for image acquisition and broadcasting through close flight. However, it was deemed suitable for short and medium distance flights because of the fast battery consumption. In the case of helicopter rotorcraft drone, image acquisition and broadcasting were possible, but noise and vibration caused by propellers were disadvantageous. The number of entrants to the islands totaled 410 and the main act was fishing. The proportion of entrants to the islands in Area A was higher than that of other areas, and thus it was deemed more necessary to manage the area. Broadcasting was found to have had a positive effect on the management of fishers.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.11
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• pp.51-62
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• 2003

This paper presents a novel survivor memeory management and decoding techniques with sequential backward state transition control in the trace back Viterbi decoder. The Viterbi algorithm is an maximum likelihood decoding scheme to estimate the likelihood of encoder state for channel error detection and correction. This scheme is applied to a broad range of digital communication such as intersymbol interference removing and channel equalization. In order to achieve the area-efficiency VLSI chip design with high throughput in the Viterbi decoder in which recursive operation is implied, more research is required to obtain a simple systematic parallel ACS architecture and surviver memory management. As a method of solution to the problem, this paper addresses a progressive decoding algorithm with sequential backward state transition control in the trace back Viterbi decoder. Compared to the conventional trace back decoding techniques, the required total memory can be greatly reduced in the proposed method. Furthermore, the proposed method can be implemented with a simple pipelined structure with systolic array type architecture. The implementation of the peripheral logic circuit for the control of memory access is not required, and memory access bandwidth can be reduced Therefore, the proposed method has characteristics of high area-efficiency and low power consumption with high throughput. Finally, the examples of decoding results for the received data with channel noise and application result are provided to evaluate the efficiency of the proposed method.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.4
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• pp.117-123
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• 2013

In the recent cloud storage environment, the amount of SSD (Solid-State Drive) replacing with the traditional hard disk drive is increasing. Management of SSD for its space efficiency has become important since SSD provides fast IO performance due to no mechanical movement whereas it has wearable characteristics and does not provide in place update. In order to manage space efficiency of SSD, data de-duplication technique is frequently used. However, this technique occurs much overhead because it consists of data chunking, hasing and hash matching operations. In this paper, we propose new data de-duplication method using PRAM cache. The proposed method uses hierarchical hash tables and LRU(Least Recently Used) for data replacement in PRAM. First hash table in DRAM is used to store hash values of data cached in the PRAM and second hash table in PRAM is used to store hash values of data in SSD storage. The method also enhance data reliability against power failure by maintaining backup of first hash table into PRAM. Experimental results show that average writing frequency and operation time of the proposed method are 44.2% and 38.8% less than those of existing data de-depulication method, respectively, when three workloads are used.

• The Journal of the Acoustical Society of Korea
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• v.34 no.5
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• pp.385-393
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• 2015

The speed of train has rapidly been increased in accordance with the developed railway technology. Nowadays, high-speed trains were introduced which has the speed faster than 400 km/h. In Korea, a lots of efforts were undertaken to increase the speed of train faster than 350 km/h, however noise and vibration are still the main problems to solve for realization of the high-speed train. In the case of operation speed faster than 350 km/h, it can be easily presumed that the noise and vibration damages could be increased in the train stations which are close to the passing railway tracks. Thus, the noise in the five different types of high-speed train stations were analyzed including stations built on the ground, underground, under rail, and two types on rail. The present paper predicts noises inside the stations depending on the speed of the passing trains and analyze the noise comparing with noise criteria (NC). Sound insulation performance of each part of buildings was calculated using the transmission noise formula and computer modeling, Finally, a series of processes were introduced to satisfy the aural environment with the optimum interior noise criteria by changing interior finishing materials.

• Journal of agricultural medicine and community health
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• v.35 no.4
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• pp.350-360
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• 2010

Objectives: This study was conducted to identify factors that affect medical service performance in rural health sub-centers and to develop a method to improve health sub-center performance that takes advantage of these insights. Methods: This study included 1,242 South Korean health sub-centers that had been in operation at least since December 31, 2009 as units of analysis. After adjusting for population differences between areas, the performance of medical service among health sub-centers was analyzed according to medical services performed per person. We performed t-tests, ANOVA, Scheffe's tests and multiple regression analyses. Results: The following were significant variables affecting the medical service performance of rural health sub-centers: number of hospitals and clinics, presence of community health practitioner posts, distance from health sub-centers to main public health centers, distance from health sub-centers to the nearest emergency medical facilities, and proportion of the local population aged 65 and over. In contrast, the proportion of the local population between ages 0-4 and the placement of public health doctors that had already completed their internship were not significant variables. Conclusions: The medical service performance of health sub-centers located in rural areas is significantly affected by local population and health care environment characteristics, and therefore, it is imperative to develop strategies to provide differentiated service based on these factors.

• The Journal of the Korea Contents Association
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• v.20 no.4
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• pp.358-372
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• 2020

Recently, there has been growing social interest in the use of care farms as part of therapy for neurological or mental patients and regional innovation for rural areas. Care farm, which combines the health treatment and rural innovation perspectives, is important to establish a proper governance system for mutual collaboration with various stakeholders. However, there is still a lack of research on this. Therefore, this study designed the care farm governance framework and comparatively analyzed the governance between Netherlands paradise care farm and Belgium blue farm, which are major successful care farm cases. The results showed different governance system between Netherlands and Belgium care farm in terms of institutional and financial support, regional characteristics, structure, operation, and strategy. In Netherlands, as the central government-initiated therapy-centric, care farm governance is concentrated in treatment of patient mainly supported by Ministry of Health, Welfare and Sports under the law on social support. Whereas, in Belgium, as local government-initiated agriculture-centric, care farm governance is mainly focused to lead voluntary participation of agricultural cooperatives and medical institutions in regional area. This study provides a theoretical foundation of governance type and system for the care farm research and suggests guidelines of care farm governance for the governments like South Korea consider activating care farm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.436-443
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• 2017

Recently, the development of new energy technologies has become a hot topic due to problems,such as global warming. Unlike renewable energy technologies, such as solar energy generation, solar power, and wind power, which are optimized to achieve medium or above output power, the output power of energy harvesting technology is very small and has not received much attention. On the other hand, as the mobile industry has been revitalized recently, the utility of energy harvesting technology has been reevaluated. In addition, the technology of tracking the maximum power point has been actively researched. This paper proposes a new MPPT(Maximum Power Point Tracking) control method for a TEM(thermoelectric module) for load resistance. The V-I curve characteristics and internal resistance of TEM were analyzed and the conventional MPPT control methods were compared. The P&O(Perturbation and Observation) control method is more accurate, but it is less economical than the CV (Constant Voltage)control method because it usestwo sensors to measure the voltage and current source. The CV control method is superior to the P&O control method in economic aspects because it uses only one voltage sensor but the MPP is not matched precisely. In this paper, a method wasdesigned to track the MPP of TEM combining the advantages of the two control method. The proposed MPPT control method wasverified by PSIM simulation and H/W implementation.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.13 no.2
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• pp.80-85
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• 2017

Angelman syndrome is a rare disorder caused by deletion or inactivation of genes on the maternally inherited chromosome 15. This neurodevelopmental disorder is characterized by developmental and intellectual delay, speech impairment, sleep disturbance, seizures, motor dysfunction, and frequent laughing or smiling. Orofacial characteristics include a prominent mandible, large mouth, prominent cheeks, a tendency to rest the tongue between the dental arches, excessive drooling, and excessive chewing behavior. Patients with this syndrome usually require general anesthesia even in a simple operation, because of risk of perioperative seizure during dental procedure. This is a case report about dental treatment of a 3-year-old female patient with Angelman syndrome under general anesthesia. This case suggests that the dental treatment under general anesthesia can be considered a safe component for the uncooperative, delayed developmental patients with underlying disease. Also, periodic dental exam appointment should be made to provide the patients with preventive treatments and to make them remain familiar with the dental environment.

• Journal of the Korean Society for Railway
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• v.20 no.1
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• pp.11-19
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• 2017

Since operation of railway trains is a major source of particle pollution in tunnel air, a particle removal device can be an effective measure to remove wear particles. To obtain design conditions of the particle removal device that will be installed underneath the railway trains, the wind speed and particle concentration underneath the trains were investigated using a three-dimensional ultrasonic anemometer and a DustTrak aerosol monitor, respectively. The measurements were made for the trains running on Seoul Metropolitan Subway Line 5 on February 10, 2015. The data were analyzed according to the track geometry (straight, curved) and train speed pattern (acceleration, cruising, and deceleration) between stations. Train speed was also analyzed. The average wind speed and $PM_{10}$ concentration underneath the trains were ~30% of the train speed and ${\sim}200{\mu}g/m^3$ for both straight and curved sections. Average $PM_{10}$ concentration for deceleration sections was higher than that for acceleration sections.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.3
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• pp.155-163
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• 2017

Membrane filtration has become more popular in drinking water treatment recently, since the filtration can control not only particulate matters but also pathogenic microorganisms such as giardia and cryptosporidium very effectively. Pilot-scale ($120m^3/d$ of treatment capacity) and test-bed ($25,000m^3/d$ of treatment capacity) microfiltration experiments were conducted to find optimum operating mode and the critical flux. Optimum operating mode of pilot-test was assessed as inflow 1.0 min, filtration 36.5 min, air backwash 0.9 min, backwash 1.0 min and outflow 1.0 min with 50 LMH ($L/min{\cdot}m3^$) of critical flux. Critical Flux was calculated to be $50L/m^2-h$ (within TMP 0.5 bar) based on the increase formula of the transmembrane pressure difference according to the change of time at Flux 20, 40, 56 and 62 LMH in pilot operation. Chemical cleaning was first acid washed twice, and alkali washing was performed secondarily, and a recovery rate of 95% was obtained in the test-bed plant. The results of operating under these appropriate conditions are as follows. Turbidity of treated water were 0.028, 0.024, 0.026 and 0.028 NTU in spring, summer, autumn and winter time, respectively. Microfiltration has superior treatment capability and performance characteristics in removing suspended solids and colloidal materials, which are the main cause of turbidity and important carrier of metal elements, and it has shown great potential in being an economically substitute to traditional processes (sand filtration).