• Journal of Advanced Marine Engineering and Technology
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• v.23 no.3
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• pp.300-310
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• 1999

A constant-volume combustion chamber is developed to measure the burnt gas temperature over the wide ranges of equivalence ratio from 1.5 to 2.7 and pressure from 0.1 to 2.7 and pressure from 0.1 to 6 MPa by two-color method. The combustion temperature is also calculated by the conventional two-region model. The premixed fuel rich propane-oxygen-inert gas mixtures under high pressures are simultaneously ignited by eight spark plugs located on the circumference of combustion chamber with 45 degree intervals. The eight converging flames compress the end gases to high pressures. The transmissiv-ity in the chamber center during the final stage of combustion at the highest pressure is measured by in situ laser extinction method. Comparisons are made with the combustion temperatures between two-color method and two-region model. It is found that the burnt gas temperature mea-sured by two-color method is higher than that calculated by two-region model because of being the negative temperature gradient on the calculation and the temperature distribution of light path-length on the measurement and the burnt gas temperature for the turbulent combustion is higher than that of the laminar combustion under the same conditions because the heat loss for turbulent combustion is lower due to the shorter combustion period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.1
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• pp.48-54
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• 2017

The ecological characteristics of Pseudoblennius cottoides were investigated off Dolsan Island, Yeosu, Korea, from June to December, 2001. Their habitats were the reef zone and surrounding embankment which was covered with seaweeds. Their range of total length (TL) was 6.10-8.40 cm (n=15), and the individuals (over 8.10 cm) of them accounted for in June. It was 8.60-15.7 cm (n=67), and the individuals 11.1-12.0 cm in TL accounted for in October, 2001. The female to male sex ratio was 1:0.48 (n=185). The gonads were in the shape of a rod and the ovaries were large in size. In June, the histology of the seminiferous tubules was observed. In August, the testicles appeared. In October, spermatocyte was observed in the testes, and ovaries were observed in relation to circumference popularity and oocyte.

• Journal of Nutrition and Health
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• v.32 no.1
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• pp.3-9
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• 1999

This study examined the effect of dietary lipids and ovariectomy(OVX) on bone mass in rats. The experimental animals were divided into sham operation(S) or OVX(O) groups and then each group was divided into soybean oil(SS, OS), beef tallow(SB, OB), and fish oil(SF, OF) diet group. Experimental diets were fed for 16 weeks. Weight gain tended to be higher in OVX groups than in sham groups. Weigth gain was the highest in beef tallow group (SB) and the lowest in fish oil group(SF). There were no difference in weight, length, breaking force, strength and circumference of femur mong groups. However, volume of femur tended to be higher in OVX groups than in sham groups. Ash content of femur was significantly lower in OVX than sham groups but there were no difference between SB and OB group. Ca content in the soybean oil and beef tallow group were not influenced by OVX but Ca content in fish oil group was significantly higher in OF than SF group. The SB group showed the hyighest Ca content and the SF group showed the lowest Ca content. P content of femur was significantly lower in OVX groups than in sham groups but there were no difference between SB and OB group. The SS group showed the highest P content and the OS and OF group showed lower P content compare to other groups. From this result, it suggested that beef tallow positively influenced maintenance of bone mass by means of accumulation of body fat in ovariectomy.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.8
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• pp.1212-1216
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• 2006

This experiment was conducted to determine and compare some characteristics of the meat and carcass of rabbits aged 11 weeks according to sex. In the experiment thirty male and thirty female New Zealand White rabbits were slaughtered. The weights and percentages of cold carcasses, skin with head and limbs, liver, kidney, heart, lung, fore legs, hind legs, breast and ribs, loin and abdominal wall were recorded. The values for carcass length, lumbar circumference, pH in the muscles of Biceps femoris and Longissimus dorsi, meat to bone ratio and cooking loss were also determined. The mean values for cold carcass weight and cold dressing percentage were 832 g and 48.77% in male and 849 g and 48.69% in female, respectively. In this study no significant differences were shown between male and female rabbits in the characteristics of carcass and meat except the value of pH of Longissimus dorsi muscle which was markedly higher in males than that in females meat. Slaughter weight was positively correlated with the weights of carcass, skin with head and limbs, lung, liver, kidney, heart and weights of joints (p<0.01) and dressing percentage (p<0.05).

• Journal of Korean Academy of Nursing
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• v.41 no.5
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• pp.613-622
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• 2011

Purposes: Study purpose were to describe growth patterns of premature infants in weight, length and head circumference from birth to 40th week of corrected ages (CA) and to explore factors affecting patterns. Methods: A longitudinal descriptive study was conducted with 267 premature infants. They were categorized into 2 groups; GA group with measurements at birth and the CA group with measurements at CA, which was categorized into 3 groups (group 1-3) by WHO guideline for gestational age (GA) at birth. Results: GA group presented greater measures in all than CA group at same week of life. Among CA groups, group 3 showed the highest measurements, up to 37 weeks of life, though this disappeared at 38-40 weeks. Reversely, group 1 revealed the highest growth rates in all measures, followed by group 2 and group 3. Significant interaction was observed in all measures between week of life and any type of groups. Conclusions: Higher measures in GA group, as well group 3 among CA groups, supported the superiority of intra-uterine environment overriding quality of regimen from NICU. Regardless of growth acceleration, smaller infants remain smaller, indicating that intra-uterine thrifty phenotype may continue at least up to the 40th week of CA.

• The Journal of Korean Physical Therapy
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• v.21 no.4
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• pp.51-56
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• 2009

Purpose: This study examined the difference in the static balance ability according to the visual cues and postural tasks in normal subjects. Methods: Thirty participants (12 male, 18 female; mean age $24.63\pm1.43$ years) stood barefoot on a force platform in a one-legged stance, tandem Romberg stance and tandem Romberg with neck extension stance with a visual cue open and closes. The static balance was assessed by the center of pressure (CoP), surface electromyography root mean square (RMS) of the leg muscles according to the stance position. Results: In the CoP tests, the difference in the unit path length and circumference area was affected by the visual cue according to the stance posture (p<0.01). In the RMS tests, the difference in the tibialis anterior and medial gastrocnemius muscle was affected by visual cue in accordance with the stance posture (p<0.01). Conclusion: The visual cue and postural task affect the balance ability in normal subjects. Therefore, this study provides clinical evidence that the balance and postural control can be improved. Therapeutic intervention, such as an obstacle course, and a lower leg muscle performance program with a change in the base of support can affect the balance and postural control.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.423-426
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• 2009

POSTECH Graduate School of Wind Energy is trying to upgrade the PMSG used for Unison U50 to 900 kW class. Intensive optimization efforts are carried out the reduce the axial size and total weight of the generator while increasing the rated output to 900 kW. The generator features 3.32m stator inner radius, 671mm stator length, 84 pole, 25 rated rpm and 31.6kN/$m^2$ shear force density. To reduce the gross weight, the stronger magnetic material is applied with optimal magnet size resulting lowest cogging torque. Also, instead of stator skewing the stator, the magnet position along the circumference is optimized to further reduce the cogging torque. This scheme eliminates the stator skewing procedure and may enhance the productivity. This method also reduces the total harmonic distortion. In this report, upgrade method, no-load line to line voltage and phase voltage, cogging torque, loss calculations and thermal analysis are presented.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.443-443
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• 2009

Cogging Torque is induced by the magnetic attraction between the rotor mounted permanent magnet(PM) and the stator teeth. This torque is an unwanted effect causing shaft vibration, noises, metal fatigues and increased stator length. A variety of techniques exist to reduce the cogging torque of PM generator. Even though the cogging torque can be vanished by skewing the stator slots by one slot pitch or rotor magnets, manufacturing cost becomes high due to the complicated structure and increased material costs. This paper introduces a new cogging torque reduction technique for PM generators that adjusts the azimuthal positions of the magnets along the circumference. A 900 kW class PMSG model is simulated using a three dimensional finite element method and the resulting cogging torques is analyzed using the Maxwell tensor stress tensor. Using the 3D simulation, the end contribution of the cogging torque is accurately calculated.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.11
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• pp.1487-1499
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• 2007

In this study, photographs of 600 Korean females aged from 20 to 50years old were indirectly measured in Venus face 2D program. The measurements were analyzed by statistical methods. The purpose of this study was to differentiate the facial types of adult women for the beauty industry. As a result of factor analysis, 6 factors were selected the key factors of facial shape: head height(factor 1), head width(factor 2), side face width(factor 3), head width and circumference(factor 4), face length(factor 5), and side face width(factor 6). We categorized facial type into 5 groups with the previous 6 factor. 5 types were most common facial shapes: Oblong face(type 1), Square face(type 2), Oval face(type 3), Round face(type 4), Triangle face(type 5). The results of facial type analysis were showed that Round face(26.6%), Triangle face(25.3%), Oval face(22.3%), Square face(20.0%), Oblong face(5.7%).

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.5
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• pp.637-647
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• 2004

The goal of this study was to develop bicycle apparel pattern for women cyclists. To investigate the pattern of bicycle apparel in Korea, anthropometric data were collected using direct and indirect measurements from October 2002 to July 2003. Three female subjects were recruited from forty measured women cyclists for pilot test. The differences between the responses of prototype bicycle apparel and existing bicycle apparel were compared using mean, standard deviation and t-test. The outfits for cyclists was completed through the three times rectification. Based on the results from the fit and appearance testing, I concluded as follows: The mean value of the center back length, back width, sleeve out-seam, bust ＆ thigh circumference, and weight of cyclists are more than the mean value of the non-cyclists. The result of fit evaluation by judges shows that there is a significant differences in the response to the shoulder, collar, movement of arms of jersey and movement of upper legs, crotch fit and general fit of shots. The result of appearance test between two outfits is no differences the mean value except the waist ease when sitting on cycle. Prototype bicycle apparel pattern for women cyclists developed and tested in this study have the potential to increase field performance and appearance.