• The Journal of the Acoustical Society of Korea
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• v.22 no.3
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• pp.224-232
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• 2003

In this paper, efficient deployment method of sensors and target positioning performance with respect to measurement error are dealt with. Active sonar can be categorized into Monostatic, Bistatic, Multistatic sonar, and characteristics of respective sonar are different. Assuming that each sensor can receive range and angular information, we compare the performance of Monostatic, Bistatic, and Multistatic systems. And we suggest Weighted least square (WLS) which gives the weight to former case, LS. In particular. adopting suggested method we investigate the target positioning performance according to number of sensor, distance from transmitter to receiver, and propose efficient arrangement rule for Multistatic sonar configurations. According to the experimental results, RMSE of Multistatic sonar is found to be superior to Monostatic and Bistatic by 35.98%. 37.45% respectively, and WLS is superior to LS approximately by 7.4% in average. Furthermore, as the difference of respective sensor's variance is large, it is observed that the improvement ratio of target positioning performance is increased.

• Journal of Korean Foot and Ankle Society
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• v.14 no.2
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• pp.161-164
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• 2010

Purpose: The purpose of this study is to find out the normal angles of the talus-1st metatarsal angle, the talo-horizontal angle and calcaneal pitch angle for diagnosis of foot deformity in Korea. This would be helpful as it would provide a basic angular measurement of flat and cavus foot that indicates the need for operation. Materials and Methods: Within a period of four months from January 2007 to April 2007, We have established 600 feet of 300 males without trauma history of foot. The source to image distance is 40 inches and erect weight bearing radiographs are obtained in anteroposterior and lateral projections. The significant angular measurements that define flat or cavus foot are the talus-1st metatarsal angle, the talo-horizontal angle and calcaneal pitch angle. Results: The mean age was 21 years (19-22 years) old. The mean talus-1st metatarsal angle was $0{\pm}6.9{^{\circ}}$, the mean talo-horizontal angle was $25.8{\pm}4.5{^{\circ}}$ and the mean calcaneal pitch angle was $23.9{\pm}5.1{^{\circ}}$. Conclusion: We can consider that mean talus-1st metatarsal angle, talo-horizontal angle and calcaneal pitch angle are $0{\pm}6.9{^{\circ}}$, $25.8{\pm}4.5{^{\circ}}$ and $23.9{\pm}5.1{^{\circ}}$ as an normal angle limit of young age in Korea.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.6
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• pp.457-465
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• 2009

Lithium batteries are widely used in mobile electronic devices due to their higher voltage and energy density, lighter weight and longer life cycle compared to other secondary batteries. In particular, high demand for lithium batteries is expected for electric cars. In case of lithium batteries used in electric cars, driving distance must be calculated accurately and discharging should not be done below the level of making it impossible to crank. Therefore, accurate information about state of charge (SOC) becomes an essential element for reliable driving. In this paper, a new method of estimating the SOC of lithium polymer batteries by using AC impedance is proposed. In the proposed method, parameters are extracted by fitting a curve of impedance measured at each frequency on the equivalent impedance model and extracted parameters are used to estimate SOC. Experiments were conducted on lithium polymer batteries with similar capacities made by different manufacturers to prove the validity of the proposed method.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.46 no.2
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• pp.108-115
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• 2020

Objectives: Kinesiology tape (KT) creates a pulling force on the skin, thus improving blood and lymph flow by alleviating hemorrhage and congestion of lymphatic fluid. The authors hypothesized that the use of KT could be beneficial for the management of complications after head and neck surgery and designed this study to evaluate the effects of KT on swelling, pain, and trismus after enucleation of mandibular dentigerous cysts with third molar extraction. Materials and Methods: Forty patients who underwent enucleation of a dentigerous cyst with extraction of the mandibular third molar were selected. The patients were randomized into two groups (n=20 each): a KT group, where KT was applied after surgery in addition to basic postoperative care, and a control group, where patients received basic postoperative care without KT application. Swelling, pain, and trismus were evaluated before surgery (T0) and on postoperative days 1 (T1), 2 (T2), and 3 (T3). Cyst volume, gauze weight for assessing bleeding, and operation time were recorded. Results: There was a significant difference between the two groups in the change in swelling up to T1 and the change in swelling between T1 and T2. The maximum swelling in the KT group was significantly less than that in the No-KT group and maximum swelling appeared faster in the KT group than in the No-KT group. Both groups showed a mild pain response but there was no significant difference between the two groups. There was no significant difference on interincisal distance change between the two groups. There were no correlations between cyst volume, bleeding, operation time, and maximum swelling. Conclusion: KT can effectively manage facial swelling after oral and maxillofacial surgeries such as cyst enucleation and third molar extraction, thus improving postoperative patient satisfaction levels and quality of life.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.11
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• pp.1613-1621
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• 2002

An electromagnetic flowmeter(EMF) essentially averages the velocity distribution over the pipe cross- sectional area, and the measured value is dependent on the velocity profiles. In this study, installation effects of 90$^{\circ}$long elbow(KS B 1522, ISO 3419) on the EMF characteristics was investigated. A commercial EMF was adopted and the distribution of magnetic field in the electrodes cross section was measured. In the experiment, the national flow standard system, of which measurement uncertainty was evaluated in accordance with ISO 17025 recommendation, was used fur characterization of EMF. The leading line has 150D long straight pipe to established a fully developed flow before entering into the elbow and the elbow was installed downstream of it. then the flowmeter was tested within 50 D from the elbow. The installation effects of the flowmeter were investigated by varying the mean velocity(Reynolds No.)in pipe section, the locations and the direction of electrodes plane.($\phi$) From the experimental results, we find the optimal conditions to get most accurate measurements. Generally, the deviations from the calibration value were less than 0.5 % in farther than 10D distance from the elbow and the direction of electrode plane. $\phi$ = 90$^{\circ}$yielded the smallest measurement deviation. These characteristics were shown consistently in turbulent region regardless of the mean Reynolds number.

• The Korean Journal of Community Living Science
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• v.15 no.1
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• pp.35-47
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• 2004

This study investigated the health and eating habits of college students who commute long distances to and from their schools. Among ninety-eight commuters, 61.2% were females while 38.8% were males. The mean round-trip commuting time was 4.60 hours and the mean number of days of commuting was 3.68. The proportion of underweight females (26.7%) was significantly greater than that of underweight males (5.3%). Conversely, the proportion of overweight males was 34.2% while only 1.6% of the females were overweight, and the difference was statistically significant. The mean number of health-related problems was 1.47 for males and 1.90 for females. Commuting affected the eating habits (90.8%) and health status more noticeably among females. Physical discomfort such as fatigue, stomach discomfort, constipation, weight change, and insomnia appeared after commuting. Irregular meal times, skipping breakfast, frequent overeating and insufficient time to eat were the most prevalent problems indicated. The scores for dietary attitude and eating habits were 20.1/30 and 27.6145, for males and females respectively. Although self-perceived nutrition knowledge was significantly related to dietary attitude and satisfaction with meals, a correlation was not found between self-perceived nutrition knowledge or dietary attitude and the eating habits score. The more concerned the parents were about student's eating habits, the higher the score relating to eating habits. The parents' concerns about students' meals and the food expenses were significantly correlated, but no correlation was found between the food expenses and the eating habits score. Consistent parental concern and encouraging students to maintain good eating habits are recommended. University administrators should also be aware of the needs of commuters and provide a proper and adequate food-related environment for the students.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.6
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• pp.1260-1262
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• 2002

A particular type of ginseng that grows in mountainous regions of Korea is known as Sansam, a term meaning literally mountain grown ginseng. Sansam has recently gained a reputation among some Korean people who believe its health benefits are superior to that of other types of ginseng. Misuse of Sansam has resulted from misinformation that has circulated about the health benefits of its use. Due to insufficient study and research, Korean Oriental Medicine academia does not presently have enough credible information about Sansam to properly educate the public in its use. However, we do have a responsibility to perform adequate study and research so that correct information may be provided. To date, only cursory investigation of the physical characteristics of the Sansam plant have been conducted. This limited investigation was performed in July 2002, at Sobaek Mountain. The branches, leaves, stems, peduncles, fruits, and roots (head, main and fine roots) were observed. The fine roots grew and spread in a large area around the main roots so that harvesting the plants required digging out the soil a considerable distance from the main roots. The plants grew in a northwesterly direction, with a gradient of 40 degrees. They had four branches. Three of the branches had six leaves, while one had five leaves. Each plant had 40 fruits. The roots of the plants grew in a shape similar the Chinese character for mountain. The roots were milky in color. The average weight of the plants was 42.5 grams.

• Parasites, Hosts and Diseases
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• v.54 no.4
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• pp.439-446
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• 2016

Toxoplasmosis is a protozoan disease that is caused by Toxoplasma gondii in livestock and humans. Due to its medical and veterinary importance, it is essential to study the seroprevalence of T. gondii infection among humans and animals in various parts of the world. The major objective of this study was to determine the seroprevalence and spatial distribution of toxoplasmosis in small ruminants (sheep and goats) of north-eastern region, Pakistan. A total of 1,000 animals comprising of sheep (n=470) and goats (n=530) were examined for T. gondii infection by using ELISA. An epidemiological data was collected in the form of questionnaire. A surface has been generated by using method of interpolation in Arc GIS with the help of IDW (inverse distance weight). The results showed higher seroprevalence of T. gondii in goats (42.8%) as compared to sheep (26.2%). The seroprevalence was higher in females as compared to males in all examined ruminants. Similarly, there is a wide variation in the seroprevalence of T. gondii in different breeds of sheep and goats showing higher seroprevalence in Teddy (52.8%) and Damani breed (34.5%) of goat and sheep's, respectively. The geographical and spatial distribution of T. gondii shows that it is widely distributed in different parts of the north-eastern region of Pakistan. Our results suggest widespread environmental contamination with T. gondii oocysts and that small ruminants could be a potentially important source of T. gondii infection if their infected meat is consumed undercooked.

• Korean Journal Plant Pathology
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• v.3 no.4
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• pp.239-244
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• 1987

Low molecular weight plant ribonucleic acids including potato spindle tuber viroid(PSTV) RNA were electrophoresed in 0M to 8M urea-gradient polyacrylamide gels. The electrophoresis was carried on in a urea - gradient gel system with 1/40 and 1/10 dilution of TBE buffer at three different temperatures, $17^{\circ}C,\;37^{\circ}C\;and\;57^{\circ}C$. The most effective separation of PSTV - RNA molecules into circular and linear forms was achieved at the highly denaturing temperature of $57^{\circ}C$ and at 1/40 dilution of TBE buffer. The electrophoretic mobility of the denatured circular viroid-RNA molecules is dependent mainly on the concentration of urea. In addition, a low concentration of TBE buffer would increase the separation distance between the circular and linear forms of PSTV-RNA molecules in the denaturing urea-gradient gel system

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.183-190
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• 2017

Carton clamp truck is widely perceived as the high-efficient handling equipment of factory premises and warehouse by its capability of palletless handling. Therefore, the significance of a lab-based handling simulation is becoming higher with the growth of clamp truck usage. In this study, preliminary FEA and design of handling test courses for the lab-based simulation of carton clamp truck handling were performed, and the PSD analyses were performed for the modified one for the test course proposed by Park et al. (2017) as well as ASTM D 6055 and ISTA 3B standards. For the vibration in all directions, the vibration energy intensity analyzed by ISTA 3B standard showed higher than that by the other two cases. A FEA was performed for the handling operation of the sudden stop of the clamps after lifting the target HCP (heavyweight refrigerator corrugated package, w=180 kgf) up to the specified height. The slip distance between the clamp arm and the target HCP was 0.85 mm. The simulation result of 0.85 mm was 3.7 times lower than the experimental result (3.2 mm) obtained by Park et al. (2017), and it was estimated that the deviation comes from both the experimental error by weight imbalance of target HCP, and excessive simplification during the FE modelling of target HCP.