• School Mathematics
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• v.2 no.1
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• pp.29-51
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• 2000

In this study, we tried to suggest an example of the analysis on the use of mathematical manipulatives. Taking algebra tiles as an example of mathematical manipulatives, we analysed several effects resulted from the use of algebra tiles. The algebra tiles make it possible to do activities that are needed to introduce and explain the distributive law and factoring. The algebra tiles have a several advantages; First of all, This model is simple. Even though they cannot make algebra easy, this model can play an important role in the transition to a new algebra course. This model provides access to symbol manipulation for students who had previously been frozen out of the course because of their weak number sense. This model provides a geometric interpretation of symbol manipulation, thereby enriching students' understanding, This model supports cooperative learning, and help improve discourse in the algebra class by giving students objects to think with and talk about. On the other hand, The disadvantages of this model are as follows; the model reinforces the misconception that -x is negative, and x is positive; the area model of multiplication is not geometrically sound when minus is involved; only the simplest expressions involving minus can be represented; It is ineffective when be used the learning of already known concept. Mathematics teachers must have a correct understanding about these advantages and disadvantages of manipulatives. Therefore, they have to plan classroom work that be maximized the positive effect of manipulatives and minimized the negative effect of manipulatives.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.279-281
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• 2003

We analysed the operating properties of resistive type superconducting fault current limiters (SFCLs) based on YBCO thin films with a single line-to-ground fault. When a single line-to-ground fault occurred, the short circuit current of a fault phase increased up to about 6 times of transport currents immediately after the fault instant and was effectively limited to the designed current level within 2 ms by the resistance development of the SFCL. The fault currents of the sound phases almost did not change because of their direct grounding system. The unsymmetrical rates of a fault phase were distributed from 6.4 to 1.4. It was found that the unsymmetrical rates of currents were noticeably improved within one cycle after the fault instant. We calculated the zero phase currents for a single line-to-ground fault using the symmetrical component analysis. The positive sequence resistance was reduced remarkably right after the fault but eventually approached the balanced positive resistance component prior to the system fault. This means that the system reaches almost the three-phase symmetrical state in about 60 ㎳ after the fault. The ground currents were almost 3 times of the zero phase mts since most of the fault currents flowed through the grounding line.

• The Journal of the Acoustical Society of Korea
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• v.20 no.1E
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• pp.3-6
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• 2001

Sound pressure level (SPL) measurements were performed on a controlled test track vehicle coast-by runs of a passenger vehicle with six different sets of tires across a range of temperatures. A small but significant reduction of noise level with positive temperature increases was observed for some tires. The temperature gradient of the different tires at 80㎞/h ranged from -0.07 to + 0.01 dB/℃. Frequency analysis of the tire noise identified that noise content in the range of 1,300 to 1,900Hz was particularly sensitive to temperature changes. Differences in SPL due to speed and tire type were much greater than that due to temperature.

• Korean Journal of Veterinary Research
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• v.42 no.3
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• pp.393-396
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• 2002

A 5 kg, seven-month-old, female Pekingese dog was presented to Seoul National University Veterinary Medical Teaching Hospital with the history of anorexia and exercise intolerance. Muffled cardiac sound and mild abdominal pain were detected in the physical examination. In positive contrast peritoneography, contrast medium was observed in enlarged pericardial sac through the diaphragm. According to the history taking, physical examination and contrast radiographic study, the dog was diagnaosed congenital peritoneopericardial diaphragmatic hernia. Following midline celiotomy, herniated falciform ligament and greater omentum were repositioned to abdrminal cavity. The diaphragmatic defect was closed with absorbable suture. Clinical signs related to peritoneopericardial hernia disappeared immediately after surgical treatment. There had been no evidence of recurrence of the peritoneopericardial hernia for 1 year.

• Journal of the korean veterinary medical association
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• v.14 no.3
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• pp.157-160
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• 1978

One case of left-sided abomasal displacement is described. The examination methods available to the practitioner do lead to a positive diagnosis except one of the splashing sound of abomasum. Preference is given to laparotomy (rumenotomy) from the left si

• Journal of Nutrition and Health
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• v.34 no.1
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• pp.98-111
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• 2001

The article demonstrates a method of studying human health and nutrition by applying a multi-disciplinary approach and examines how humans developed and survived by adjusting to their environment. This process involves physiological, cultural and genetic adaptation both independently and interactively. This study postulates that a sound human health may be the result of balance between nutrition and environmental conditions. It is noted that there is a positive correlation between malaria and fava bean intake, and sickle cell anemia and cassava intake. It is also suggested that the difference in disease structure in soybean and non-soybean consumption cultures can be explained by an ecological approach to studying nutrition. This study further suggest that the relationship between nutrition and socio-cultural system. epidmiological study of nutrition and cultural environment nutrition and conceptual characteristics, nutrition and food intake pattern, nutrition and health sociological functions and the physioloical, cultural and genetic adaptation can all be stimulating research subjects to be studied form and ecological point of view. This article also includes the results from a series of ecological studies conducted by the author investigating the relationship between nutritional status of Korean breast-feeding mothers and the composition of the human milk and also the Vitamin D status of Korean and their lifestyle. (Korean J Nutrition 34(1):98-111, 2001)

• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2126-2134
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• 2015

The present study suggests a localization method for the first (S₁) and the second (S₂) feature of heart sounds, based on an algorithm involving frequency filtering, energy detection, and interval regulation. Localization accuracy was evaluated by comparing the algorithm with the traditional Hilbert transform-based localization method. Results show that the sensitivity and the positive predictivity value of proposed method, respectively, were 97.27 % and 99.94 % in S₁ detection and 94.99 % and 100 % in S₂ detection.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.497-500
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• 1999

A 4 years old male mixed breed dog, which weighed 25.5 kg, referred to Veterinary Teaching Hospital at College of Veterinary Medicine in Chonnam National University, because of chronic hindleg lameness. Click sound by flexion and extension of stifle joint, positive reaction by cranial drawer movement, fat pad sign and tibial position in cranial drawer position on the lateral radiographic view, medial patellar luxation (grade II), and lameness score 2.5 at standing and 2 at walking in right hindleg were showed. Under general anesthesia with enflurane, after medial arthrotomy, it was performed to remove remnants of cranial cruciate ligament and torn medial menisci and joint closed. In modified retinacular imbrication technique, one lateral fabellar/tuberosity suture, one medial fabellar/tuberosity suture, and one imbrication suture adjacent to the patella were placed. At 9 days after operation, lameness score 0 was observed and general condition was excellent.

• Journal of the Korean housing association
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• v.17 no.1
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• pp.19-27
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• 2006

This research deals with the residential environment for the elderly and describes characteristics to give a positive effect on elderly's health and quality of life in Sweden. Five elderly care home recommended by a municipality staff in Stockholm are surveyed on $01\~03$ October 2003. The results of this study are as follows: 1) homelike atmosphere is regarded as a basic design concept and is applied to size, materials, scale, color, and furniture of elderly housing in Sweden, 2) regarding of the exterior features, it is similar to the ordinary house rather than institution building, 3) arrangement of spaces is planned for several small groups consisting of 6-8 residents, 4) open-space planning on public kitchen and dinning room allows residents to feel comfortable when they can hear a sound and smell a meal, 5) private flat is to provide amenities for sleeping, rest, storage, social interaction, meals, hygiene and other every activities

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.04a
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• pp.193-198
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• 2009

This study focuses on building an effective environmental control system for the ubiquitous housing environment. In order to build an effective environmental control system that will provide a comfortable, pleasant, and convenient environment for residents, information on how people cognize the indoor and outdoor environmental conditions, information on human beings, and information of the space should be studied. Also more studies need to be done in which method would be the best way to integrate these informations that would affect the users in the most positive way. The current environmental control system only carries the information on providing separate information of environmental factors such as light, temperature, humidity, heat, and sound. However, it is difficult to understand the energy efficiency of an architectural element through this system. Therefore, this study proposes an energy monitoring system utilizing spatial information.