• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.2
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• pp.209-216
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• 2018

High-resolution satellite imagery is used in diverse fields such as meteorological observation, topography observation, remote sensing (RS), military facility monitoring and protection of cultural heritage. In satellite imagery, low-resolution imagery can take place depending on the conditions of hardware (e.g., optical system, satellite operation altitude, image sensor, etc.) even though the images were obtained from the same satellite imaging system. Once a satellite is launched, the adjustment of the imaging system cannot be done to improve the resolution of the degraded images. Therefore, there should be a way to improve resolution, using the satellite imagery. In this study, a super resolution (SR) algorithm was adopted to improve resolution, using such low-resolution satellite imagery. The SR algorithm is an algorithm which enhances image resolution by matching multiple low-resolution images. In satellite imagery, however, it is difficult to get several images on the same region. To take care of this problem, this study performed the SR algorithm by calibrating geometric changes on images after applying automatic extraction of feature points and projection transform. As a result, a clear edge was found just like the SR results in which feature points were manually obtained.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.39 no.2
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• pp.35-44
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• 2002

The translation and the rotation of camera occur global motion which affects all over the frame in video sequence. With the video sequences containing global motion, it is practically impossible to extract exact video objects and to calculate genuine object motions. Therefore, high compression ratio cannot be achieved due to the large motion vectors. This problem can be solved when the global motion compensated frames are used. The existing camera motion estimation methods for global motion compensation have a large amount of computations in common. In this paper, we propose a simple global motion estimation algorithm that consists of linear equations without any repetition. The algorithm uses information .of symmetric points in the frame of the video sequence. The discriminant conditions to distinguish regions belonging to distant view from foreground in the frame are presented. Only for the distant view satisfying the discriminant conditions, the linear equations for the panning, tilting, and zooming parameters are applied. From the experimental results using the MPEG test sequences, we can confirm that the proposed algorithm estimates correct global motion parameters. Moreover the real-time capability of the proposed technique can be applicable to many MPEG-4 and MPEG-7 related areas.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.7
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• pp.48-56
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• 2011

Recently, new storage device SSD(Solid State Disk) based on NAND flash memory is gradually replacing HDD(Hard Disk Drive) in mobile device and thus a variety of research efforts are going on to find the cost-effective ways of performance improvement. By increasing the NAND flash channels in order to enhance the bandwidth through parallel processing, DRAM buffer which acts as a buffer cache between host(PC) and NAND flash has become the bottleneck point. To resolve this problem, this paper proposes an efficient low-cost scheme to increase SSD performance by improving DRAM buffer bandwidth through scheduling techniques which utilize DRAM multi-banks. When both host and NAND flash multi-channels request access to DRAM buffer concurrently, the proposed technique checks their destination and then schedules appropriately considering properties of DRAMs. It can reduce overheads of bank active time and row latency significantly and thus optimizes DRAM buffer bandwidth utilization. The result reveals that the proposed technique improves the SSD performance by 47.4% in read and 47.7% in write operation respectively compared to conventional methods with negligible changes and increases in the hardware.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.49 no.1
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• pp.15-24
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• 2012

In this paper, we suggest the dynamic-response-free SMPS using a new high-resolution DPWM generator based on switched-capacitor delay technique. In the proposed system, duty ratio of DPWM is controlled by voltage slope of an internal capacitor using switched-capacitor delay technique. In the proposed circuit, it is possible to track output voltage by controlling current of the internal capacitor of the DPWM generator through comparison between the feedback voltage and the reference voltage. Therefore the proposed circuit is not restricted by the dynamic-response characteristic which is a problem in the existing SMPS using the closed-loop control method. In addition, it has great advantage that ringing phenomenon due to overshoot/undershoot does not appear on output voltage. The proposed circuit can operate at switching frequencies of 1MHz~10MHz using internal operating frequency of 100 MHz. The maximum current of the core circuit is 2.7 mA and the total current of the entire circuit including output buffer is 15 mA at the switching frequency of 10 MHz. The proposed circuit has DPWM duty ratio resolution of 0.125 %. It can accommodate load current up to 1 A. The maximum ripple of output voltage is 8 mV. To verify operation of the proposed circuit, we carried out simulation with Dongbu Hitek BCD $0.35{\mu}m$ technology parameter.

• Bulletin of the Society of Naval Architects of Korea
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• v.54 no.4
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• pp.39-46
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• 2017

Jack-up drilling rigs are widely used in offshore oil and gas exploration industry. It is originally designed for use in the shallow waters less than 60m of water depth; there is growing demand for their use in deeper water depth over 150m and harsher environmental conditions. In this study, global in-place analysis of jack-up rig leg for North-sea oil well is performed through numerical analysis. Firstly, environmental conditions and seabed characteristics at the North-sea are collected and investigated measurements from survey report. Based on these data, design specifications are established and the overall basic design is performed. Dynamic characteristics of the jack-up rig for North-sea are considered in the global in-place analysis both leg and hull and the basic stability against overturning moment is also analyzed. The structural integrity of the jack-up rig leg/hull is verified through the code checks and the adequate safety margin is observed. The uncertainty in jack-up behaviour is greatly influenced by the uncertainties in the soil characteristics that determine the resistance of the foundation to the forces imposed by the jack-up structure. Among the risks above mentioned, the punch-through during pre-loading is the most frequently encountered foundation problem for jack-up rigs. The objective of this paper is to clarify the detailed structure and installation engineering matters for prove the structural safety of jack-up rigs during operation. With this intention the following items are addressed; - Characteristics of structural behavior considering soil effect against environmental loads - Modes of failure and related pre-loading procedure and parameters - Typical results of structural engineering and verification by actual measurement.

• Archives of Reconstructive Microsurgery
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• v.15 no.1
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• pp.17-25
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• 2006

Twelve cases in eleven patients with segmental bone defects were treated with contralateral fibula free flap and ipsilateral island fibula flap in an antegrade, retrograde or bidirectional flow fashion. Five cases were managed with free flaps and seven were with ipsilateral fibula island transfer. Among seven cases, antegrade fashion was three, retrograde was three, and bidirectional was one. All patients were related with open tibial fractures and its sequelae except one who had open foot bone fracture. According to Gustilo's classification, ten patients were type IIIb and one was type IIIc. Basically, antegrade-flow flaps based on the peroneal vessels as in the conventional free flap were used for the proximal or middle one-third tibial defects. On the contrary, retrograde-flow flaps based on the communicating branch between the peroneal and posterior tibial vessels were used for the middle or distal one-third of the tibia. Bidirection-flow flap based on intact peroneal vessels were used for the middle portion of the tibia. The patients who have undergone ipsilateral fibula island flap had one of the following problems: a previously failed free flap, below-knee amputation of the opposite leg because of open tibial fracture, refusal to use the contralateral sound leg, or poor general condition to stand a lengthy operation. Six of the patients who have got ipsilateral fibula island flap also had an associated fibula fracture on the same leg, which was ultimately used as one of the osteotomy sites. The follow-up period was from 1 to 10 years. Two cases of free flap were failed: one patient had below-knee amputation and the other patient had ipsilateral fibula transfer. Other cases were successful and excellent hypertophy of the transferred fibula was achieved. Time to bone union ranged from 4 to 11 months. Time to full weight bearing was from 5 to 13 months after surgery. All of the transferred fibulas showed hypertrophy after weight bearing. In one case, stress fracture was developed during ambulation, which was healed conservatively. Nonunion occurred in two cases, which were treated with a long leg cast and cancellous bone graft, respectively. Length discrepancy of the legs was noted. The limb was shorter by an average 0.5 cm in three cases, longer by 1.1 cm in one case. In the case of island fibula transfer, limited arc of rotation was not a problem. Other disabling complications were not seen. We believe that these diverse modalities using a vascularized fibula will make us more comfortable to handle major bone defects.

• Journal of Environmental Impact Assessment
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• v.24 no.4
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• pp.332-343
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• 2015

It would be the most effective way to have government take care of social problems and hazardous material danger due to odor. It is also well known that odor acceptance and their willingness to pay for resolving the odor problem vary person by person. This is why public sector's intervention is required to get ride of any possibility of market failure resulted from negative external effect of human. This paper has tried to do empirical research based on survey of residents who are currently living in the area of Ochang industrial complex in North Chong-chung province. According to the empirical research results, first of all, it was proven residents' perception of legal regulation has a negative effect on odor acceptance. That is, the more residents are aware of law and regulation, the less they tend to accept odor. In addition, resident's perception on need to improve odor regulation has a positive impact on their odor acceptance. Finally, residents' satisfaction on the legal complaints to local government has an interaction effect to causative relationship between the perception of improving odor regulation and odor acceptance.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.6
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• pp.367-375
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• 2003

The aim of this study was to investigate the soil physical properties and the traction characteristics of paddy field before tillage by a computer simulation. Soil physical properties, such as soil moisture content, bulk density, soil hardness, and soil texture were measured in the twelve rice production area. Mathematical model based on dimensional analysis which include soil physical properties and vehicle factors was used for the computer simulation. Most of the soil texture of the investigated area was silty loam, loam and silty clay loam. Soil moisture content ranged between 20 and 40% mostly. Soil bulk density was in the range of 1,500 to $1,700kg\;m^{-3}$. Soil hardness ranged between 2 to $12kg\;cm^{-2}$ mostly. Soil hardness incorporates the effects of many soil physical properties such as moisture content, texture and bulk density, and so the range of soil hardness was greater than that of any other physical properties. The predicted net traction was in the range of 70 to 1,500 kgf depending on the area, but it was above 1,000 kgf for most of the investigated area. Thus it was concluded that 50 HP tractor can pull the four row moldboard plow considering the conventional tillage depth and width. But for the soft soil area such as Andong and Namyang, tractor itself may have mobility problem and show high slip during plowing operation.

• Korean Journal of Social Welfare
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• v.39
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• pp.128-156
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• 1999

Community Service Order is a program that holds a significant place in the system of probation. With its important role in the probation, there is an equally high expectation of the intervention from the program among the people which it serves. The problem lies in that people's understanding of the program is minimized to merely a volunteer-based social activity, which cause a division on how the program is to be run. The purpose of this research is to come up with a method that can efficiently organize the administrative plan to maximize its potentiality of the program. To adopt such a plan, "Sentencing to Service," an effective community service order program in Minnesota, U. S. A. was examined. An interview with the administrative staff, as well as a survey, using systematic sampling, with the participants was conducted to study the effective process and intervention of the program that has existed for fifteen years. The result concluded that "Sentencing to Service" is a successful program with the components of success being that of a positive support from the local community and high motivation level of the participants. In order for the program to be a positive experience for the participants, it is highly contingent upon the crew leaders. On the basis of the research findings, the following suggestions are made. First, a structured guideline for those who are involved in the program is necessary. Second, thorough training provided for the crew leaders are required and a social worker is recommended for the position of crew leader. Lastly, Community Service Order should not widen the net, but ought to serve as an alternative to incarceration.

• Journal of Korean Public Health Nursing
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• v.10 no.1
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• pp.12-22
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• 1996

Currently. exchanges of industrial workers between countries are more active than ever. and the problem of AIDS in connection with the operation of preventive educational programs has reached a point where the issue cannot be limited to native people alone any more. Based on such judgement. this research has been carried out to provide basic study materials by grasping the latent factors representing the difference between countries in the levels of right knowledge. attitude and behavior with respect to AIDS maintained by workers who have grown in different social and cultural living background. During the period from Apr. 1. 1995 to Jun. 30. questionnaires. written both in Korean and English, were distributed to Korean and Malaysian employees working at certain Korean video manufacturers. and the results of replies. given by 80 workers who were analyzed through matched sampling· method where ages and sex matched by country. were used as the research materials. The gathered materials were analyzed through the SPSS package t-test. ANOVA. factor analysis and multiple stepwise regression methods. and the following results were obtained. 1. The 2 extracted latent factors could be named 'common. social' knowledge factor and 'in-depth. psychological' knowledge factor respectively. 2. The percentile points of 'external. social' knowledge factor. in the case of Korean workers. howed 90.0 at average. a figure 13.75 points higher than those of Malaysian workers. 76.25. On the other hand. the percentile points of the 'in-depth. psychological'knowledge factor showed 70.80 at average in the case of Korean workers. a figure 7.47 points lower than those of Malaysian workers. 78.33. Meanwhile. the difference in percentile points between the 2 latent factors was 8.54 at average. indicating that the points of 'in-depth. psychological' knowledge factor was lower than those of the 'external. social' knowledge factor. 3. As for Korean workers. the percentile points of the 'in-depth. psychological' knowledge factor showed higher points in office workers than in non-office workers. and such variables exhibited in the position of workers can explain the $7\%$ of the latent factor. The percentile points of the 'in-depth. psychological' knowledge factors. in the case of Malaysian workers. showed higher points in groups who had religion than in groups who did not. and higher points in groups who obtained information from newspapers than in groups who obtained from televisions or other sources; and with these 2 variables. $26\%$ of this latent factor can be explained. The results. of analysis described so far suggest that while Korean workers possessed general level of knowledge on AIDS. they had low level of practical knowledge as far as its depth is concerned. and that they had social prejudice on patients as well as on the AIDS infection route. In addition. because the overall knowledge level of Malaysian workers. is lower than that of Korean workers. it suggests that separate programs intended for Malaysian workers are required prior to executing integrated programs.