• Publications of The Korean Astronomical Society
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• v.22 no.3
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• pp.63-73
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• 2007

In this paper, we introduce the performance test results of digital data processing system for KVN (Korean VLBI Network). The digital data processing system for KVN consists of DAS (Data Acquisition System) and high-speed recorder which called Mark5B system. DAS system performs the digitalization of analog radio signal through ADS-1000 gigabit sampler with 1 Gsps/2-bit and process the digital filtering of digital signal. Mark5B system records the output data of DFB (Digital Filter Bank) with about 1 Gbps. In this paper, we carried out the preliminary evaluation experiments of the KVN digital data processing system connected between DAS system and Mark5B with VSI (VLBI Standard Interface) interface which is designed for compatible in each VLBI system. We first performed all of the KVN digital data processing system connected by VSI interface in the world. In factory inspection phase, we found that the DAS system has a memory read/write error in DSM (Digital Spectrometer) by analyzing the recorded data in Mark5B system. We confirmed that the DSM memory error has been correctly solved by comparing DSM results with Mark5B results. The effectiveness of KVN digital data processing system has been verified through the preliminary experiments such as data transmission, recording with VSI interface connection and data analysis between DSM and Mark5B system. In future work, we will perform the real astronomical observation by using the KVN 21m radio telescopes so as to verify its stability and performance.

• Fashion & Textile Research Journal
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• v.14 no.3
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• pp.486-491
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• 2012

This study examined the sound characteristics of Taekwondo uniform fabrics to investigate the relationship between the sound parameters and the mechanical properties of the fabric as well as to provide the conditions to maximize the frictional sound of the uniform. Frictional sounds of 6 fabrics for Taekwondo uniforms were generated by the Simulator for Frictional Sound of Fabrics. The frictional speeds were controlled at low(0.62 m/s), at mid(1.21 m/s) and at high(2.25 m/s) speed, respectively. The frictional sounds were recorded using a Data Recorder and Sound Quality System subsequently, the physical sound properties such as SPL(Sound Pressure Level) and Zwicker's psychoacoustic parameters were calculated. Mechanical properties of specimens were measured by KES-FB. The SPL, Loudness(Z) values increased while Sharpness(Z) value decreased. In the physical sound parameter, specimen E had the highest SPL value at low speed and specimen B at high speed. In case of Zwicker's psychoacoustic parameters, the commercially available Taekwondo uniform fabrics(E, F) showed higher values of Loudness(Z), Sharpness(Z), and Roughness(Z), that indicates they can produce louder, shaper and rougher sounds than other fabrics for Taekwondo uniforms. The decisive factors that affected frictional sounds for Taekwondo uniforms were W(weight) as well as EM(elongation at maximum load) at low speed and WC(compressional energy) at high speed.

• Journal of the Korean School Mathematics Society
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• v.7 no.2
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• pp.81-97
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• 2004

This paper is a study on the understanding process of「Matrix and Graph」on discrete mathematics using TI-92 calculator. For this purpose, we investigated the understanding process of two middle school students learning the concepts of matrix and graph using TI-92 calculator. In this process, we collected qualitative data using recorder and video camera. Then we categorized these data as follows: students' attitude related to using technology, understanding process of meaning, expression and operation of matrix and graph, mathematical communication, etc. From this, we have the following conclusions: First, students inquired out the meaning and role of matrix by themselves using calculator. We could see that calculator can do the role of good learning partner to them. Second, students realized their own mistakes when they used calculator on the process of learning matrix. So we found that calculator could form the self-leading learning circumstance on learning matrix. Third, calculators reinforce the mathematical communication in learning matrix and graph. That is, calculator could be a good mediator to reinforce mathematical communication between teacher and students, among students on learning matrix and graph.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.8
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• pp.106-112
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• 1998

Recently, the amount of image and audio data has been increasing dramatically for high performance. According to this trend, a high-density magnetic recording system is necessitated and the tracks of magnetic tapes are getting narrower. This, in turn, requires the capstan servo system of the magnetic recording system such as DVCR to control precisely the speed and position of the capstan motor. Especially, in case of play-back, the capstan servo system should be able to position and maintain the head on the desired place of the track. To meet this requirement, digital camcorders use ATF (Automatic Track Following). In this paper, a new ATF block using discrete Fourier transform is proposed. The proposed ATF block was designed and implemented in ALTERA FPGA chips and fully tested in a real DVCR system. It is shown through experiments that the new ATF block is more cost-effective than other existing ATF blocks using digital lowpass filters. In particular, the number of logic gates can be reduced by 20% in average, compared to the existing ATF's.

• Journal of Fisheries and Marine Sciences Education
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• v.6 no.1
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• pp.11-19
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• 1994

The North Pacific midwater trawling which is one of the important fishing methods for Korean fishing industry is working in the Bering Sea and the sea near Kamchaka Peninsula. The catch by Korean midwater trawlers had been recorded about 300 thousands $^{M/_T}$ a year. Six types of midwater trawl net-ordinary midwater trawl net, super-V trawl net, super mesh trawl net, rope trawl net, super plus trawl net and kite trawl net-have been widely used by large trawlers above 1,500gt in size since 1982. Regarding the fishing efficiency, the super plus trawl net and kite trawl net were acknowledged as higher than other nets. Maximum mesh size of super-plus trawl net and kite trawl net ranges about 20m, whereas the length of net about 150m, and high-tech polyethylene is used as the material of rope part. The problems involved in the North Pacific midwater trawl net may be summarized as follows ; (1) The dimension of fishing gear is too big compared with the towing power of trawler. (2) The mesh size of the rope part is too big compared with that of the common netting part. (3) The net is often torn out in the connecting position of the rope part and the netting part. (4) The net is not matched with the trawler and the otter board in many trawlers, so the shape of the trawl gear in the water is instable. (5) The fish school located near head rope, ground rope and side rope in the net recorder is not caught in practice because of the net instability.

• Journal of the Korean Society of School Health
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• v.12 no.2
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• pp.243-262
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• 1999

Today, obesity is not recognized as a disease itself but is known to be the indirect cause of much chronic illness. Obesity has an impact on psychological disorders including severe inferiority, damage of body self-image, low self-esteem, personality disorders. The results in an increase of the mortality rate. Therefore, this study attempts to discover and evaluate stressful experience in obese teenagers. For this study, 21 girl students and 19 boy students in Pusan middle or high school located were selected. The data were collected from March to May at 1999. A tape-recorder was used under the permission of the subjects to prevent the loss of spoken information and communication. This study consisted of 563 reponses from girls and 461 responses from boys which were then classified with descriptive expressions and priority classifications. The results generated 72 common elements in girls and 54 common elements in boys. From these elements 24 syntheses of hypothetical definitions and 8 identifications of the structural definitions in both girls and boys were developed. The structural and hypothetical definitions were as follows: The analysis of the data was made through a phenomenological analytic method suggested by Van kamm, which is as follows: 1. Maladjustment to school life; lack of understanding of the teacher, insufficient exercise ability, and a feeling of burden in attending the school obesity program. 2. Conflict in family relationships; lack of understanding from the family, a feeling of alienation. 3. Conflict in friend relationships; lack of understanding among friends, constant comparisons in appearance and body with friends (in girls) and estrangement from friends (in boys). 4. Conflict in acquaintance of the opposite sex; hoping to meet the opposite sex, lack of understanding of boy friends (in girls), feelings of pain, feelings of anxiety (in girls) feelings of burden (in girls) feelings of envy (in boys). 5. Negative body image: shape of body; feelings of pain; feelings of powerlessness; feelings of discomfort, and reception; emotional disorders (in boys), and change of personality (in boys). 6. Health disorder: Physical and psychological discomfort. 7. Feelings of burden in weight control; negative experiences in weight control, interference with family and friends, the difficulty in diet therapy, feelings of burden in exercise (in girls), to be teased by the public through mass media (in boys).

• Journal of The Korean Association For Science Education
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• v.13 no.1
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• pp.31-47
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• 1993

This study was intended to find the characteristics of the middle school students' thinking processes and problem spaces when they solved the physics problems. Ten ninth grade students in Chon-Buk Do, Korea were participated in this study. The researcher investigated their thinking processes in solving 5 physics problems on electric circuit. "Thinking aloud" method was used as a research method. The students' thinking processes were recorded using an audio tape recorder and transfered into protocols. The protocols were analyzed by problem solving process coding system which was developed by Lee(1987) on the basis of Larkin's problem solving process model. The results are as follows : (1) On the average 2.85 items were solved among 5 test items, and only one person could solve all of the items correctly. (2) Problems were solved in sequence of understanding the problem, planning, carrying out the plan, and evaluating steps regardless of the problem difficulty. (3) In regard to the thinking process steps, there was no difference between the good solvers and the poor ones. But in the detail performance of problem solving, the former was different from the latter in respect with using the design of general solving procedure. (4) The basic problem spaces by the item analysis were divided into two classes. One was the problem space by using Qualitative approach in problem solving, and the other was one by using Quantitative approach. As novices in physics problem solving, most of the students used the problem space by using the Quantitative approach.

• Women's Health Nursing
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• v.3 no.2
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• pp.180-191
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• 1997

When women are removed with their matrix which is a emotionally significant organ of symbol in psychologically adapting themselves to mother and woman, that is threatened and injured with woman role decisively. The nursing for women with hysterectomy is limited to medical treatment and the nursing related to troubles in psychology, emotion they experience in general situation due to operations is hardly realized. New basis for nursing can be realized when we both have relation with lived human experience related th health and become to be a part of it. We need to catch their experience due to the loss of matrix to understand women with hysterectomy. The subjects of the study were nine patients who were admitted to a gynecological ward of a hospital in Seoul, suffering from vaginal bleeding, back pain, abdominal pain and so on and diagnosing as non-cancer. The data were collected from April to May 1997 by listening to the subjects' expression of their experience and by participant observation of the subjects' reactions. A tape-recorder was used under the permission of the subjects, to prevent the loss of spoken information. The result of the study was as follows : The data on burden content from the interview were categorized as psych-emotional, physical, personal interaction, financial burden and maternal role burden. The factors which have influence on the burden of the subjects are an offer of information, support system, age, occupation, economic situation, family history, character, season, the existence of ovary and religion. In conclusion, since we ascertained that the nursing in the process of recovery decide the quality of life, though women with hysterectomy undergo various burden experience and adapt to it in the end, it is necessary to give them enough information and educate husband, having on important effect on the burden experience, to be a good supporter. And technically skilled nurses of consultant are thought to be able to contrive better qualitative life of women with hysterectomy as an important bridge between the subjects and their required information, since the nurses have their well-formed position of relationship of confidence through continuous contact with patients and their family.

• Ocean and Polar Research
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• v.36 no.2
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• pp.179-187
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• 2014

Directly searching for undiscovered hydrothermal vent sites is inefficient due to the practical difficulty of comprehensively imaging vent fields. Thus, most searches for hydrothermal vent sites rely on the detection of hydrothermal plumes from water column observation. Detecting and measuring the hydrothermal plumes are the most efficient way to infer the presence and distribution of hydrothermal vents. Both the array of vertical casting and lateral towing are the most common methods to discover hydrothermal plumes. In this study, we compared results of cast and tow-yo operations along the same section of a spreading center with a distance of 20.5 km in the North Fiji Basin for mapping hydrothermal plumes. Operation of CTD tow-yo provides a detailed pattern of plumes which enable us to locate the hydrothermal vents. On the other hand, identification of hydrothermal activity can be determined effectively by CTD cast with additional analysis of geochemical tracers. Reduction in the operating time is another advantage of CTD cast operation, especially for regional-scale survey. Our results show that the combination of CTD cast and tow-yo would improve the efficiency of the hydrothermal plume survey to locate new hydrothermal vent sites.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.1-10
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• 2013

With the help of information technology, PVR has been evaluated as an innovative device that brings epochal changes for program selection and convenience of receivers with the convergence between broadcasting and telecommunication. Satellite broadcasters introduced PVR service to strengthen its interactive function. This study analyzed PVR user behavior and how it changed the existing TV viewing behavior through satellite subscribers. The results revealed that PVR subscribers mainly used it for time shifting like VCR use. FUrthermore, heavy PVR users watched TV more than on average and enjoyed a divers genre of programs. This study provides scholarly implication for PVR using behavior and its effects and its useful information for contents and marketing strategy to help PVR service popularization.