• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.27 no.1
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• pp.1-12
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• 1991

An experiment has been carefully designed and performed to verify the theory for the echointergration technique of estimating the density of fish school by the use of steel spheres in a laboratory tank. The spheres used to simulate a fish school were randomly distributed throughout the insonified volume to produce the acoustic echoes similar to those scattered from real fish schools. The backscattered echoes were measured as a function of target density at tow frequencies of 50kHz and 200kHz. Data acquisition, processing and analysis were performed by means of the microcomputer-based sonar-echo processor including a FFT analyzer. Acoustic scattering characteristics of a 36cm mackerel was investigated by measuring fish echoes with frequencies ranging from 47.8kHz to 52.0kHz. The fluctuation of bottom echoes caused by the effects of fish-school attenuation and multiple scattering which occurred in dense aggregations of fishes was also examined by analyzing the echograms of sardine schools obtained by a 50kHz telesounder in the set-net's bagnet, and the echograms obtained by a scientific echo sounder of 50kHz in the East China Sea, respectively. The results obtained can be summarized as follows: 1. The measured and the calculated echo shapes on the steel sphere used to simulate a fish school were in close agreement. 2. The waveform and amplitude of echo signals by a mackerel without swimbladder fluctuated irregularly with the measuring frequency. 3. When a collection of 30 targets/m super(3) lied the shadow region behind another collection of 5 targets/m super(3), the mean losses in echo energy for the 30 targets/m super(3) were about -0.4dB at 50kHz and about -0.2dB at 200kHz, respectively. 4. In the echograms obtained in the East China Sea, the bottom echoes fluctuated remarkably when the dense aggregations of fish appeared between transducer and seabed. Especially, in the case of the echograms of sardine school obtained in a set-net's bagnet, the disappearance of bottom echoes and the lengthening of the echo trace by fish aggregations were observed. Then the mean density of the sardine school was estimated as 36 fish/m super(3). It suggests that when the distribution density of fishes in oceans is greater than this density, the effects of fish-school attenuation and multiple scattering must be taken into account as a possible source of error in fish abundance estimates. 5. The relationship between mean backscattering strength (, dB) and target density ($\rho$, No./m super(3)) were expressed by the equations: =-46.2+13.7 Log($\rho$) at 50kHz and =-43.9+13.4 Log($\rho$) at 200kHz. 6. The difference between the experimentally derived number and the actual number of targets gradually decreased with an increase in the target density and was within 20% when the density was 30 targets/m super(3). From these results, we concluded that when the number of targets in the insonified volume is large, the validity of the echo-integration technique of estimating the density of fish schools could be expected.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.3
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• pp.287-295
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• 2016

Involuntary physical activity induced by the avoidance of electrical shock leads to improved endurance exercise capacity in animals. However, it remains unknown whether voluntary stand-up physical activity (SPA) without forced simulating factors improves endurance exercise capacity in animals. We examined the effects of SPA on body weight, cardiac function, and endurance exercise capacity for 12 weeks. Twelve male Sprague-Dawley rats (aged 8 weeks, n=6 per group) were randomly assigned to a control group (CON) or a voluntary SPA group. The rats were induced to perform voluntary SPA (lifting a load equal to their body weight), while the food height (18.0 cm) in cages was increased progressively by 3.5 every 4 weeks until it reached 28.5 cm for 12 weeks. The SPA group showed a lower body weight compared to the CON group, but voluntary SPA did not affect the skeletal muscle and heart weights, food intake, and echocardiography results. Although the SPA group showed higher grip strength, running time, and distance compared to the CON group, the level of irisin, corticosterone, genetic expression of mitochondrial biogenesis, and nuclei numbers were not affected. These findings show that voluntary SPA without any forced stimuli in rats can effectively reduce body weight and enhance endurance exercise capacity, suggesting that it may be an important alternative strategy to enhance endurance exercise capacity.

• Journal of Aquaculture
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• v.20 no.3
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• pp.147-153
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• 2007

The present study was performed to evaluate sitological quality of the cultured and wild river puffer, Takifugu obscurus. Proximate composition, the content of extractive nitrogen, the content of nucleotides and their related compounds, total and free amino acid, and fatty acids were analysed and sensory evaluation in the muscle of the river puffer were compared. The cultured river puffer had a higher moisture content compared to the wild fish, while there was no significant difference in crude lipid, crude protein and ash contents. Nucleotides and their related compounds including ATP, ADP, AMP, IMP, HxR and Hx were detected. The result from analyzing ATP-related compound showed difference in total content by wild and cultured river puffer, and IMP content that had largest influence upon the savory taste of sliced raw fish, was higher in the cultured fishes than wild ones. Breaking strength level of the wild river puffer was higher than that of the cultured fish. High levels of C16:0 and C18:0 were shown in all samples and -3 polyunsaturated fatty acid content were not different between the cultured and wild river puffers (P>0.05). Total 17 amino acids were detected in the samples, and most of the samples had high contents of glutamic acid, aspartic acid, lysine and leucine and low contents of cystine, histidine, methionine and tyrosine. The result from surveying free amino acid content of wild and cultured river puffer showed difference in content, but generally taurine and lysine content for the whole free amino acid held the most part. There was no significant difference in texture, flavor and overall acceptance score between the cultured and wild fishes (P>0.05).

• The Korean Journal of Air & Space Law and Policy
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• v.20 no.2
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• pp.59-158
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• 2005

When a military aircraft suffers damages due to the defects in its design, manufacturing or notification, all of which are generally understood as products liability defects, the obvious compensation is sought as it would in other consumer good case. However, there exist clear yet unappreciated difference between general consumer goods and military aircraft, as far as products liability law is concerned - some sort of recovery should be obtained even when there exist only defects, not damages, to the aircraft because of the implication of defective parts is much grave than what can be expected in a consumer goods case. While certain anticipatory measures do exist in manual or at negotiation stages for the safety of military aircraft, such measures are ineffective, if not ambiguous, in recovery effort in the post-accident stage In another word, the standardized military procurement contract manuals and boilerplate forms do not appreciate the unique and dangerous military nature of military aircraft. There are many unique legal issues which can arise when trying to prevent defective aircraft or parts, or to recover compensations for accident due to such defects. At two-level, the government should establish legal system (or countermeasures if you'd like) for purchasing safer military aircraft. First, one should be able to work with legal ground and policy that allows selecting and purchasing safer goods - the purpose of such contract is not litigious, but rather in acquiring what are most reliable. Second, in case the defects do arise and lead to damages, solid legal principles and instructions should be established for effectively pursuing appropriate company, (usually a aerospace industry giant with much experience) for products liability - the purpose of such pursuit is inevitable for a public official, since he or she is no private business man with much flexibilities, even to the point of waiving such compensatory right for future business purposes. This article tries to identify problems in methods of procuring military aircraft or parts - after reviewing on how the military can improve on legal and policy grounds for procuring what will be the focus of future military strength, it will offer some of the ways to effectively handling and resolving a liability issues.

• Composites Research
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• v.14 no.3
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• pp.18-31
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• 2001

Interfacial and microfailure properties of the modified steel, carbon and glass fibers/cement composites were investigated using electro-pullout test under tensile and compressive tests with acoustic emission (AE). The hand-sanded steel composite exhibited higher interfacial shear strength (IFSS) than the untreated and even neoalkoxy zirconate (Zr) treated steel fiber composites. This might be due to the enhanced mechanical interlocking, compared to possible hydrogen or covalent bonds. During curing process, the contact resistivity decreased rapidly at the initial stage and then showed a level-off. Comparing to the untreated case, the contact resistivity of either Zr-treated or hand-sanded steel fiber composites increased to the infinity at latter stage. The number of AE signals of hand-sanded steel fiber composite was much more than those of the untreated and Zr-treated cases due to many interlayer failure signals. AE waveforms for pullout and frictional signals of the hand-sanded composite are larger than those of the untreated case. For dual matrix composite (DMC), AE energy and waveform under compressive loading were much higher and larger than those under tensile loading, due to brittle but well-enduring ceramic nature against compressive stress. Vertical multicrack exhibits fur glass fiber composite under tensile test, whereas buckling failure appeared under compressive loading. Electro-micromechanical technique with AE can be used as an efficient nondestructive (NDT) method to evaluate the interfacial and microfailure mechanisms for conductive fibers/brittle and nontransparent cement composites.

• Korean Journal of Poultry Science
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• v.41 no.4
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• pp.323-329
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• 2014

The objective of this experiment was to investigate the effect of dietary supplementation of copper-soy proteinate (Cu-SP) and herbal mixture (HBM) on growth performance, blood parameter, and immune response in laying hens. A total 800 Hy-Line Brown laying hens (60 weeks old) were randomly allotted to 1 of 4 dietary treatments : (1) Control : control diet, (2) Cu-SP : control diet + 100 mg/kg Cu-soy proteinate, (3) HBM : control diet + 0.15% herbal mixture, and (4) Cu-SP + HBM : control diet + 100 mg/kg Cu-soy proteinate + 0.15% herbal mixture. Each treatment was replicated 5 times with forty birds units were arranged according to randomized block design. Feeding trial lasted 5 weeks under 16L : 8D lighting regimen. The diet and water were available ad libitum. Result indicated that during feeding trial of the experiment, hen-day egg production was significantly (P<0.05) higher in Cu-SP and HBM treated groups than control. However, feed intake, feed conversion ratio, egg weight, broken and shell less egg production were not significantly influenced by treatments. Eggshell strength was significantly (P<0.05) higher in Cu-SP than control. Eggshell thickness, eggshell color, egg yolk color, Haugh unit were not significantly influenced by treatments. The level of WBC and stress index (heterophil : lymphocyte) were higher in supplemented groups than the control. The concentration of plasma IgG was higher in supplemented groups than the control. The result of this experiment showed that dietary copper-soy proteinate or herbal mixture tended to improve egg production and affect positively on immune response of laying hens.

• Journal of Preventive Medicine and Public Health
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• v.20 no.1 s.21
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• pp.10-39
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• 1987

Mortality rate and causes of death are regarded as an index of strength as well as level of development of a country. However, there is no accurate data for the causes of death in Korea due to lack of systematic vital data collection system. The objective of this study was to define the causes of death of the school teachers, its changing pattern, cause-specific mortality rate, and geographic variation. The study population included all of the teachers in primary school, middle and high schools, and college who joined in Korean Teachers' Union between 1968 and 1985 that provided a total of 1,972, 069 person-years to observe (1,384,911 man-years, 587,158 woman-years). There were 3,678 deaths in this period (3,377 males, 301 females). The most common cause of death was neoplasm which was followed by the diseases of circulatory system. The proportion of death of neoplasm was 1.5 times higher than that of the general population. Causes of death were classified into 5 major groups (neoplasm, diseases of circulatory system, accidents and poisoning, diseases of liver, and all others). The mortality rates of diseases of circulatory system and all others for general population were 4 to S times higher than those for the teachers. However, mortality rates of neoplasm and diseases of liver were only about 2 times higher than those for teachers. Mortality rate of liver cancer for teachers was higher than gastric cancer mortality rate which is the reverse in general population. The crude death rate was 2.12 per 1,000 person-years for male and 1.00 for female which is one-third of the crude death rate of general population. Crude death rate of study population was higher in rural area than in urban area. However, mortality rate of neoplasm for male was higher in urban area than in rural area while mortality rates of all other causes were higher in rural area. For female, mortality rates of neoplasm and diseases of circulatory system were higher in urban area and the rates for all other causes were higher in rural area. Crude death rate was lowest in Gyeongin area and highest in Yeongnam area. The mortality of neoplasm for male accounted the highest proportion of all death in Gyeongin, Chungcheong and Yeoungnam areas while the mortality of neoplasm and mortality of circulatory system accounted the same proportion in Jeonra area. For female, the mortality of disease of circulatory system accounted the highest proportion in Gyeongin and Yeoungnam and Jeonra areas. Proportion of death due to accidents and poisoning was high in Chungcheong area and death due to all other causes was high in Yeoungnam area. The most common cause of death for male by city and province was neoplasm in Seoul, Busan, Daegu, Gyeonggi, Chungnam, Chungbuk, Gyeongnam and Gyeongbuk. Diseases of circulatory system was the leading cause of death in the rest of city and provinces. The leading cause of death for female was diseases of circulatory system in Seoul, Incheon, Chungbuk, Chungnam, and Gyeongbuk, neoplasm in Busan, and accident and poisons in all other cities and provinces. The mortality rates of male were above 2 per 1,000 person-years in Jeju, Gyeongbuk, Gyeongnam, Daegu, and Chungbuk, and it was below 1.5/l,000 in Seoul, Incheon and Gyeonggi. The mortality rate of female was above 1.2/1,000 person-years in Gyeongnam and Incheon while it was below 0.5/l,000 in Daegu, Geonggi Chungbuk and Jeju. The leading cause for male by school of employment was neoplasm in all levels of school with a remarkably higher rate in the professors of college. Leading cause of death for female was disease of circulatory system in primary schools, high schools and college but neoplasm in middle schools. There was no death due to liver diseases in middle and high school teachers and college professors and no death due to all other category in high school teachers and college professors, in females. High school teachers and the highest mortality rate and college professors showed the lowest mortality rate. Temporal trend of mortality was examined in three periods; period I ($1968{\sim}1974$), period II ($1975{\sim}1979$), and period III ($1980{\sim}1985$). The leading cause of death for male was diseases of circulatory system in period I and II but neoplasm in period III. Such trend of decreasing diseases of circulatory system and increasing neoplasm was observed in female. Overall mortality rate was decreased over the 3 periods. The mortality rates of diseases of circulatory system, liver disease and all others were decreased in male but the mortality rates of neoplasm and accident and posions was increased. Female showed a similar trend to male but the mortality rate of liver diseases was increased. Mortality rates of diseases of circulatory system, neoplasm and liver diseases increased with age of teachers up to 50 years of age but decreased in 60 years of age. Mean age at death due to each cause was higher in male than female by $4{\sim}10$ years. However, the mean age at death of the teachers was $2{\sim}5$ years lower than that of the general population in all causes of death and the sex difference in the mean a2e at death was smaller ($2{\sim}3$ years) in general population. In sex ratio of mortality, male was higher than female in almost all diseases except suicide and maintained a high ratio. The general population showed universally high ratio in male like teachers, and more or less did regular patterns in mortality with ratio smaller.

• Women's Health Nursing
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• v.7 no.4
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• pp.518-535
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• 2001

Nursing practices should be based on the understanding of human beings. In order to understand human beings, it is important to study the lifestyles and thoughts of people in their natural environment. In this sense, the cultural aspects of a society need to be studied for a culture-bound nursing service. Child care, which is an important element of nursing, is also strongly influenced by the culture of a society. Therefore, a cultural study is necessary to understand the child-rearing practices of any society. The major purpose of this dissertation is to provide basic foundations for developing a culture-based theory for nursing intervention through studying traditional cultural elements of child care in Korean society. The study examined child-rearing practices in a small village on Koje Island in the southern part of Korea. It utilized ethnographic methodologies including participatory observations and in-depth interviews. The study participants were 9 Korean mothers living on Koje Island. The average age was 52. The data were collected between July in 1998 and December in 1999. The average number of interviews per person was 7-8, and the duration of each interview was approximately 2 hours. The data were analyzed using the Spradley Analytical Method. The following 9 major child-rearing aspects of mothers on Koje Island were discovered as a result of the study: 1. Firstly, mothers on Koje Island were mostly concerned about the "Old Birth Goddess' Curse", especially during their child's early years. This concern was evidenced by their careful behavior when their child was very young and by their praying to the Old Birth Goddess not to be jealous of their babies. 2. Secondly, they wished their children to live a different and better life than themselves. It was represented by their strong motivation toward their children's education as well as their expectation for their children's success. In traditional Korean culture, Korean people think that the rise and fall of the household depend on their offsprings. Therefore, Korean mothers wish their children attain to a higher level of social status through education. 3. Third, mothers are concerned about their children's righteousness. Mothers on Koje island expect their children to live with discretion, justice, strength, respect, harmony, and to do their best in life. 4. Next was an 'anticipation of their children's happy marriage'. The attributes of this category were an 'anxiety about their children's married life', and 'an expectation of a good spouse for their children'. Because Korean people believe that only a son can continue the bloodline of a family, especially Korean mothers have a great concern of the possibility of their daughters not having a son after marriage. Also they have different expectations toward their daughter-in-laws than son-in-laws. 5. Korean mothers also derived their satisfaction from their son. It was characterized by 'excessive affection toward their son', 'dependency on their son', and 'being afraid of their married daughter having a girl like themselves'. Korean society has been a patriarchy. Therefore, a son is beloved as someone who will take care of his old parents, be in charge of ancestral rites, and provide a daughter-in-law who can conceive a son. 6. The sixth category concerned 'the differences in their expectations for their children'. The attributes in this category were 'different expectations depending on their children's gender', 'different expectations depending on their children's ability', and a 'great sympathy toward children with low abilities'. Korean mothers expect their son to become better than their daughter. 7. The seventh category was related to their 'roles in child-caring practices'. Traditionally a child was raised in an extended family system in Korea So it was not the sole duty of a mother to bring up the child. Korean mothers used to receive much help rasing children from their in-laws, and family members. On the other hand, many children grew up by themselves, because their mothers were very busy taking care of housework. Furthermore, many children also grew up in poverty. 8. Mothers also had issues related to 'conflicts in child rearing'. They were characterized by 'lack of understanding', 'rudeness of children', and 'giving vent to one's anger'. 9. Finally, mothers regretted not doing their best in child-rearing practices. It was characterized by a 'bitter feeling of repentance', 'feeling irritated', and 'feeling of unsatisfaction'.

• Journal of the Korean Applied Science and Technology
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• v.35 no.2
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• pp.519-531
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• 2018

The purpose of this study was to investigate the effects of combined exercise program on short physical performance battery, bone mineral density and parathyroid hormone levels in elderly women. This study subjects were 22 elderly female volunteers, aged 65-75 years and they divided into the combined exercise group(n=11) and the "no exercise" control group(n=11). The combined exercise included the line dance program performed twice per week for 60 minutes and the resistance exercise program performed once per week during 12 weeks. Exercise intensity was progressively increased from RPE "fairly light" to "slightly hard" (from 11 to 14). The findings of this study were as follows; Short physical performance battery(Balance test, gait speed, and rising from a chair five times) and bone mineral density (lumbar spine L2~L4 bone densities, and the T-score) were significantly increased after 12 weeks in the exercise group compared to the baseline. The PTH level was significantly decreased in the exercise group compared to the baseline. In conclusion, regular and continuous physical activity was effective for improving short physical performance and had a positive effect on bone mineral density and parathyroid hormone. With aging, women have decreased muscle strength and bone density and therefore, it is strongly recommended that women need to carry out continuous physical activity to prevent disease and ensure a healthy retirement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.480-489
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• 2017

Blood flow restriction(BFR) exercise is defined as low intensity and short term exercise using pneumatic pressure belts at the top of limbs, which affects the physiological functions of the body. The purpose of this study was to investigate the effects of walking exercise with BFR on inflammatory index, isokinetic muscle function, and thigh circumference in obese women. Eleven obese women(> BMI $25kg/m^2$ & > body fat 30%) wore pneumatic pressure belts on both femurs and performed walking exercise twice per day, 3 days/wk for 4 weeks (walking 2 min; resting 1 min). Data analysis was carried out using paired t-test. Body weight, BMI, and body fat significantly decreased after exercise(p<.05), and right thigh circumference significantly decreased(p<.05). The concentration of plasma IL-6 significantly increased(p<.05) after exercise. TNF-${\alpha}$ level was not statistically different but tended to slightly increase. CRP slightly decreased, although it did not reach statistical significance after exercise. Muscle strength significantly increased in the $60^{\circ}/sec$ of right/left side extension, left side flexion, and $180^{\circ}/sec$ of left side extension after training(p<.05). These results suggest that 4 weeks of blood flow restriction walking exercise has positive effects on inflammatory index and isokinetic muscle function. Therefore, we consider that blood flow restriction exercise can be used for treatment of obesity, related chronic diseases, and metabolic syndrome. Further, blood flow restriction exercise for a short time has similar effects as a high intensity resistance program.