• Food Science of Animal Resources
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• v.39 no.1
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• pp.139-150
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• 2019

This study aimed to determine the suitable point of sale and consumption of different quality grade (QG) Hanwoo short loin during aging period, based on physicochemical, sensory, and microbiological quality. Short loins obtained from the carcasses of 13 Hanwoo steers and 2 bulls with 5 different QGs (1++, 1+, 1, 2, and 3) were analyzed over 28 d. QG and aging time had significant effect on water holding capacity, color, shear force, total volatile basic nitrogen (TVBN) content, and sensory traits. Higher QG groups generally exhibited a lower shear force, nucleotide content, and water holding capacity, and higher $L^*$, $a^*$, and $b^*$ values. Acceptable tenderness (shear force <5.4 kg) in QG 1++, 1+, 1, and 2 was achieved on days 7, 14, 16, and 18, respectively, and QG 3 showed a shear force of 6.8 kg, even after 28 d. Regardless of QG, TVBN content below threshold levels (20-30 mg%) was observed throughout the 28 d aging period, while total plate counts above 7 Log CFU/g were seen at 21 d. In conclusion, it is recommended that Hanwoo beef with QG 1++, 1+, and intermediate QG (1 and 2) should be sold or consumed between 7 and 21, 14 and 21, 16 and 21 d, respectively. Beef with QG 3 should be sold or consumed within 21 d, based on microbial growth, even though it has not achieved desirable tenderness. For this reason, an additional tenderizing process is recommended before this beef is ready for consumption.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.433-439
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• 2020

This study, which was designed to improve and increase the utilization of female elk, examined the possibility of collecting their embryos during the non-reproductive period using ultrasound-guided Ovum Pick-Up (OPU) technology. Once follicles in the ovaries of an elk were observed, the embryos were retrieved through the absorption of the follicles using an OPU ultrasound probe. Fifty-seven embryos were retrieved from 85 follicles, giving a retrieval rate of 67.1%. Morphological evaluation of the recovered embryos revealed 14.0% embryos to be in grade A, 19.2% in grade B, 15.7% in grade C, and 50.8% in grade D. The developmental efficiency of the retrieved embryos was also investigated using in vitro maturation, in vitro fertilization, and in vitro culture. After cultivating 28 embryos through in vitro fertilization, 19 embryos were found to be fertilized; the fertilization rate was 67.9%. Four embryos developed to the blastocyst stage, indicating a 14.3% development rate. This study confirmed that the production of fertilized embryos from a seasonal breeder, such as elk, is possible via the ultrasound-guided OPU method. If the efficiency of in vitro fertilization and in vitro culture can be improved through further research, it will help improve the efficiency of elk embryo production through the transplantation of their fertilized embryos.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5005-5014
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• 2012

The purpose of this study was to compare and analyze the effects of fitness walking exercise on physique, BMI(body mass index) and physical fitness of 5th and 6th grade elementary children. The subjects for this study were 200 children(57 boys and 39 girls in the 5th grade, and 59 boys and 45 girls in the 6th grade) at S Elementary school in Busan. The students were divided into 3 groups. Group 1 walked more than 500 km. Group 2 walked less than 500 km but more than 200 km and Group 3 walked less than 200 km for 6 months. The result of exercising for 6 months affected the physique, BMI and physical fitness of the students analyzed as follows: In physique, height, weight and BMI had significantly positive increased in the 5th and 6th grade boys and girls in all groups as comparing before and after exercising. In physical fitness, there were significantly positive increased on 50 m run, sit-ups, standing long jump, sit-and-reach, 1000 m run-walk had in all groups by stages(group 1 > 2 > 3) as comparing before and after exercising. In compare groups after exercising, there were significantly positive increased in physical fitness on group 1 more than group 3. These results indicate that fitness walking exercise by long time is effective to improve physique and physical fitness in normal elementary school students. However, for fitness walking exercise of the positive effects are necessary to change of teachers and parents personal mind.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.4
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• pp.1-6
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• 2005

In this study, on automatic ultrasonic testing system is used to detect defects of flawtest specimen. We study the effects of the difference of ultrasonic damped rate of the different materials on the judgment of defects. The results indicate that the difference of sensitivity compensating quantity is 2dB, and the judgment is correct over $90\%$ when a specimen is judged as a defect when it exceeds third grade.

• The Pure and Applied Mathematics
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• v.4 no.2
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• pp.105-110
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• 1997

The distribution of staff in a hierachial organization has been studied in a variety of forms and models. Results here show that the promotion process follows a binomial distribution with parameters n and $\alpha=e^{-pt}$ and the recruitment process follows a poisson distribution with parameter $\lambda$. Futhermore, the mean time to promotion in the grade was estimated.

• Journal of the Korean Home Economics Association
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• v.43 no.2
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• pp.33-40
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• 2005

This study compared the volatile aroma components in high grad Korea, Chinese and Japanese green tea. The aroma components of green tea were analyzed and compared. Aroma compared. Aroma compounds were extracted by a simultaneous distillation and extraction method using Likens and Nickerson's extraction apparatus. The concentrated aroma extract was analyzed and identified by GC and GC-MS. All the green tea samples contained relatively large amounts of terpene alcohols such as linalool, geraniol and nerolidol. The Korean green tea (A) manufactured in Cheju island contained remarkably large amounts of geraniol (9.12 %) and linalool (5.18 %). The Korean green tea (B) manufactured in Hawgae contained remarkably large amounts of geraniol (5.85 %) and linalool (5.33 %). The Korean green tea (C) manufactured in Bosung contained remarkably large amounts of linalool (7.79 %) and Z-jasmone (3.08 %). The Chinese green tea (D) manufactured in Longjing contained remarkably large amounts of geraniol (3.43 %) and linalool (2.86 %). The Japanese green tea (E) manufactured in Shizuoka contained remarkably large amoung of linalool (3.95 %) and nerolidol (2.76 %).

• Journal of Elementary Mathematics Education in Korea
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• v.24 no.1
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• pp.89-108
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• 2020

Since arithmetic is the foundation of school mathematics, it needs to be taught meaningfully in the direction of improving arithmetical thinking levels of students beyond the fluency of computing skills. Therefore, in this study, the arithmetical thinking levels of 100 students in 5th grade were analyzed by applying the arithmetical thinking level test. As a result, 82 students were at 1st level and 15 students were at 2nd level of the arithmetical thinking. I analyzed the characteristics of arithmetical thinking and types of errors and misconceptions made by the students, and derived some didactical implications for arithmetic education in elementary school mathematics.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1452-1458
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• 2004

An experiment was conducted to examine the effects of sex and market weight on performance, carcass characteristics and pork quality. A total of 224 crossbred pigs (initially 26.64 kg BW) were allotted in a $2{\times}4$ factorial arrangement in a randomized complete block (RCB) design. The variables were sex (gilts and barrows) and different market weights (100, 110, 120 and 130 kg). Average daily gain (ADG) and average daily feed intake (ADFI) were significantly higher (p<0.01) in barrows than gilts, ADFI and feed conversion ratio (FCR) increased as body weight increased (p<0.05). Gender differences were observed in carcass characteristics. Backfat thickness and drip loss were greater in barrows (p<0.01), while loin eye area (p<0.01), flavor score (p<0.05) and lean content (p<0.001) were higher in gilts. Carcass grade and water holding capacity were the highest in 110 kg market weight pigs. The 100 kg arket weight pigs showed lower juiciness, tenderness, shear forces and total palatability than the other market weights (p<0.01). Hunter values (L*, a* and b*) were increased as market weight increased (p<0.05). Hunter a* value was greater in gilts (p<0.01) but L* value and b* value were not affected by sex of pigs. Net profit [(carcass weight${\times}$price by carcass grade)-(total feed cost+cost of purchased pig)] was higher in gilts than barrows (p<0.01), and was higher (p<0.05) in the pigs marketed at 110 and 120 kg market weight compared with 100 kg market weight. These results demonstrated that gilts showed higher carcass characteristics, pork quality, feed cost per kg body weight gain and net profit compared with barrows. Moreover, 110 or 120 kg body weight would be the recommended market weight based on pork quality and net profit for swine producers.

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.4
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• pp.347-351
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• 2015

This study examines a clinical progress of treatment for the sequelae of facial palsy through Jung-ahn acupuncture. The patient in this case was diagnosed with facial paralysis a few years ago. The patient was treated with Korean medicine and Western medicine, but was given up without improvement. The paretic symptom was found out in left side of the face. Also facial spasm and epiphora caused by blepharoptosis were existed. The patient got 8 times Jung-ahn acupuncture treatment from September 18th, 2014 to September 26th, 2014. House-Brackmann facial nerve grading system(H-B scale) was implemented. On the first time of the treatment, H-B scale was Grade Ⅴ and facial nerve grading was 2/8. Facial spasm and epiphora caused by blepharoptosis in lower eyelid were appeared on facial expressions and conversation. After total 8 treatments(therapies), H-B scale was Grade Ⅲ and facial nerve grading was 5/8. The symptoms of facial paralysis and blepharoptosis were improved. Jung-ahn acupuncture is estimated to be effective in facial palsy sequela. More cases are required to develop treatment of facial palsy sequela.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.639-645
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• 2012

Waterborne polyurethane dispersion (PUD) was synthesized by capping the NCO groups of polyurethane prepolymers, prepared from isophorone diisocyanate, polycarbonate diol and dimethylol propionic acid, with aminopropyl triethoxysilane (APS). Subsequently, silylated acrylic polyurethane dispersion was synthesized by reacting the PUD with the mixture of acrylate monomers, 2-hydroxyethyl methacrylate and methyl methacrylate. The average particle size of silylated acrylic polyurethane dispersion, measured by the dynamic light scattering method, was increased from 39.0 nm to 399.8 nm by increasing the addition amounts of APS. Also, the pencil hardness of coating films of silylated acrylic polyurethane dispersion was enhanced from B grade to F grade with increasing APS content.