• Title/Summary/Keyword: 기계화

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Evaluation of the testicular toxicity caused by 2-bromopropane in rats (랫드에 있어서 2-bromopropane에 의해 유발된 정소독성의 평가)

  • Kim, Jong-choon;Lee, Hyun-sook;Yun, Hyo-in;Chung, Moon-koo
    • Korean Journal of Veterinary Research
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    • v.40 no.2
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    • pp.361-371
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    • 2000
  • It has been recently reported that 2-bromopropane (2-BP) induces male reproductive toxicity in both human and experimental animals. However, delayed effects of 2-BP on male reproductive system have not been investigated in detail. The present study was conducted to investigate the testicular toxicity of 2-BP and to determine the recovery of normal spermatogenesis in Sprague-Dawley rats. Male rats aged 5 weeks were administered 1,000mg/kg 2-BP by gavage daily for 4 weeks and sacrificed sequentially at 1, 2, 3, 4 and 12 weeks after initiation of 2-BP treatment. Testicular toxicity was evaluated qualitatively by histopathological examinations and quantitatively by reproductive organ weights, spermatid head count, and repopulation index. In the 2-BP treated rats, the body weights was significantly suppressed and the weights of testes and epididymides were also decreased in a time-dependent manner. On histopathological examination, spermatogonia in stages I-VI and preleptotene and leptotene spermatocytes in stages VII-IX were strongly depleted at 1 week of dosing. Spermatogonia were depleted extensively in all spermatogenic stages at 2 weeks. Continuing with the evolution of spermatogenic cycle, zygotene spermatocytes, pachytene spermatocytes, and round spermatids were sequentially depleted at 2, 3, and 4 weeks of dosing due to the depletion of their precursor cells. Vacuolization of Sertoli cells and spermatid retention were also observed at all time points, suggesting that 2-BP induced Sertoli cell dysfunction. At 12 weeks, after 8 weeks recovery, most of the tubules appeared severely atrophic and were lined by Sertoli cells only. Leydig cell hyperplasia in the interstitial tissue was also found. In addition, dramatic reductions in the number of spermatid heads and repopulation index were observed, indicating that 2-BP-induced testicular injury is irreversible. These results indicate that 4 weeks repeated-dose of 1,000mg/kg 2-BP results in a progressive germ cell loss due to the depletion of spermatogonia followed by long-term testicular atrophy in SD rats.

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Preservation of Washed Fresh Ginsengs by Gamma Irradiation (방사선(放射線) 조사(照射)에 의한 수세된 수삼(水蔘)의 저장(貯藏))

  • Cho, Han-Ok;Byun, Myung-Woo;Kwon, Joong-Ho;Lee, Jae-Won
    • Applied Biological Chemistry
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    • v.29 no.3
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    • pp.288-293
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    • 1986
  • The washed fresh ginsengs packed with air, vaccum and nitrogen gas were irradiated at the levels of 1,2 and 3kGy gamma radiation and then stored at $4{\sim}5^{\circ}C$ for 90days to investigate the effects of gamma radiation on microbial inactivation, eelworm disinfestation and physicochemical changes. After a 90 day storage, $2{\sim}3kGy$ irradiated groups showed 20% of weight loss and 10% of rot while non-irradiated group 100% and 20% or more, respectively. Also the irradiated groups showed somewhat lower values of specific gravity, color density and hardness immediately after irradiation, thereafter higher value of them with storage time than those of non-irradiated group. The irradiation increased the yields of ginseng extract and crude saponins but no effects on the proximate composition and TLC and HPLC patterns of saponin. The food-borne microorganisms decreased in viable cell counts by $2{\sim}3$ log cycles with $2{\sim}3kGy$ radiation and the eelworms were completely disinfested with 1 kGy radiation.

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Clinical Assessment, Panoramic and MRI Findings and Cephalometric Characteristics of Patients with Condylar Resorption (과두흡수환자의 자기공명영상 사진 평가 및 악안면 골격형태에 대한 연구)

  • Jang, Heon-Su;Hur, Yun-Kyung;Kim, Kyun-Yo;Ko, Yu-Jeong;Chae, Jong-Moon;Choi, Jae-Kap
    • Journal of Oral Medicine and Pain
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    • v.34 no.4
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    • pp.409-420
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    • 2009
  • The aim of this study was to investigate clinical assessment, panorama & MRI findings and cephalometric characteristics in 42 patients with condylar resorption, who visited in the Department of Oral Medicine Kyungpook National University Hospital at 2006. The results were as follows; 1. Clinical assessment 1) Female was 34 and male was 8, females were predominant. Distribution of age showed as follows; 10s was 14, 20s was 13, 30s was 7, 40s was 3, 50s was 4 and 60s was 1 patient. 10s and 20s were predominant. 2) Most of the patients had parafunctional habit. 2. Findings of panorama & MRI 1) Most of the patients had degree of Grade II condylar resorption by panorama taking. 2) Most of the patients had disc dislocation and belonged to the degree of stage IV by MRI taking. 3. Cephalometric Characteristics 1) SN, SAr and saddle angle in female patients were significantly smaller and SN in male patients showed only significantly smaller than normal group. 2) SNA showed no difference from the normal group in both patients. SNB was smaller and ANB was lager in female patients than normal group. 3) SN-GoMe and FMA increased in patients. 4) Total posterior facial height & ramus height were significantly smaller. 5) Mandibular body length did not show any significant difference.

Quality Characteristics of Instant Rice Noodles Manufactured with Broken Rice Flour (파쇄미 쌀가루를 이용한 즉석 쌀국수의 품질특성)

  • Choi, Eun-Ji;Kim, Chang-Hee;Kim, Young-Boong;Kum, Jun-Seok;Jeong, Yoonhwa;Park, Jong-Dae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.8
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    • pp.1270-1277
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    • 2014
  • This study investigated the quality characteristics of instant rice noodles manufactured with broken rice flour as an application of rice-processed products. We examined the physicochemical characteristics of common rice flour (CRF), broken rice flour (BRF), and CRF mixed with BRF (CBRF). Futhermore, instant rice noodles were manufactured with these three types of rice flour, and their quality and sensory characteristics were also investigated. Damaged starch content and water-binding capacity of rice flour were highest in BRF. Particle size of rice flour was significantly different among the three types. RVA pasting viscosities of BRF and CBRF were higher than that of CRF. Volume after cooking of instant rice noodles increased in rice noodles made with broken rice flour (BRN). Turbidity and cooking loss of BRN were higher than those of common rice noodles (CON). For texture properties, CON displayed the highest hardness, adhesiveness, and chewiness. In the sensory evaluation, springiness and overall acceptability values of CON were significantly higher than those of other rice noodle types (BRN and CBRN). In conclusion, BRN showed increased cooking loss and turbidity with reduced texture and overall acceptability values. The results of this study suggest that added amount of CRF may significantly increase the overall quality of instant rice noodles prepared with BRF.

Understanding Problem-Solving Type Inquiry Learning and it's Effect on the Improvement of Ability to Design Experiments: A Case Study on Science-Gifted Students (문제해결형 탐구학습에 대한 인식과 학습이 실험 설계 능력에 미친 효과 : 과학 영재학생들에 대한 사례 연구)

  • Ju, Mi-Na;Kim, Hyun-Joo
    • Journal of The Korean Association For Science Education
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    • v.33 no.2
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    • pp.425-443
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    • 2013
  • We developed problem-solving type inquiry learning programs reflecting scientists' research process and analyzed the activities of science-gifted high school students, and the understanding and the effects of the programs after implementation in class. For this study, twelve science-gifted students in the 10th grade participated in the program, which consisted of three different modules - making a cycloidal pendulum, surface growth, and synchronization using metronomes. Diet Cola Test (DCT) was used to find out the effect on the improvement of the ability to design experiments by comparing pre/post scores, with a survey and an interview being conducted after the class. Each module consisted of a series of processes such as questioning the phenomenon scientifically, designing experiments to find solutions, and doing activities to solve the problems. These enable students to experience problem-solving type research process through the program class. According to this analysis, most students were likely to understand the characteristics of problem-solving type inquiry learning programs reflecting the scientists' research process. According to the students, there are some differences between this program class and existing school class. The differences are: 'explaining phenomenon scientifically,' 'designing experiments for themselves,' and 'repeating the experiments several times.' During the class students have to think continuously, design several experiments, and carry them out to solve the problems they found at first. Then finally, they were able to solve the problems. While repeating this kind of activities they have been able to experience the scientists' research process. Also, they showed a positive attitude toward the scientists' research by understanding problem-solving type research process. These problem-solving type inquiry learning programs seem to have positive effects on students in designing experiments and offering the opportunity for critical argumentation on the causes of the phenomena. The results of comparing pre/post scores for DCT revealed that almost every student has improved his/her ability to design experiments. Students who were accustomed to following teacher's instructions have had difficulty in designing the experiments for themselves at the beginning of the class, but gradually, they become used to doing it through the class and finally were able to do it systematically.

Comparison of Clinical Efficacy Between Percutaneous Dilatational Tracheostomy and Surgical Tracheostomy (경피적 확장 기관절개술 (Percutaneous Dilatational Tracheostomy)의 시술 용이성 및 합병증)

  • Ahn, Jong-Joon;Koh, Youn-Suck;Chin, Jae-Yong;Lee, Ki-Man;Park, Wann;Hong, Sang-Bum;Shim, Tae-Sun;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong;Lim, Chae-Man
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.6
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    • pp.1277-1283
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    • 1998
  • Background : Surgical tracheostomy(ST) is usually performed by surgeons in operating room. For a patient with mechanical ventilation, however, transportation to operating room for ST could be dangerous for patients. In addition, ST is often delayed due to unavailability of operating room or surgeon. Percutaneous dilatational tracheostomy(PDT), although novel in Korea, is gaining popularity as a bedside procedure in the hospitals of western countries. We evaluated the technical ease and safety of PDT in comparison with ST. Method : Thirty-eight patients in medical intensive care unit (ICU) who were either under mechanical ventilation for more than 7 days or required airway protection, were randomly assigned to ST(18 patients) or PDT(20 patients). Between two groups, there was no significant clinical difference except that female to male ratio was higher in the ST group. ST was performed by second year residents of the department of otolaryngology while PDT was performed by third grade medical resident and pulmonologist under bronchoscopic guide using Ciaglia Percutaneous Tracheostomy Set(Cook Critical Care, Bloomington, USA) in medical ICU. The following factors were compared between two groups : number of delayed cases after the decision for tracheostomy, procedural time, complications related to tracheostomy. Results : Delayed cases were 11 in ST group and 3 in PDT group (P<0.05). Procedural time was significantly shorter in PDT group ($15.6{\pm}7.1min$) than in ST group ($29.1{\pm}11.6min$, P<0.0001). Complications related to tracheostomy occurred in 5 cases in ST group : accidental decannulation (1), subcutaneous emphysema (2) and minor bleeding (2), and in 4 cases in PDT group : minor bleeding (2), subcutaneous emphysema (1) and premature extubation (1) (P>0.05). Conclusion : Since percutaneous dilatational tracheostomy was easy to practice and its complications were not different from surgical tracheostomy, PDT can be a useful bedside procedure for mechanically ventilated patients.

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Response Modeling for the Marketing Promotion with Weighted Case Based Reasoning Under Imbalanced Data Distribution (불균형 데이터 환경에서 변수가중치를 적용한 사례기반추론 기반의 고객반응 예측)

  • Kim, Eunmi;Hong, Taeho
    • Journal of Intelligence and Information Systems
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    • v.21 no.1
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    • pp.29-45
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    • 2015
  • Response modeling is a well-known research issue for those who have tried to get more superior performance in the capability of predicting the customers' response for the marketing promotion. The response model for customers would reduce the marketing cost by identifying prospective customers from very large customer database and predicting the purchasing intention of the selected customers while the promotion which is derived from an undifferentiated marketing strategy results in unnecessary cost. In addition, the big data environment has accelerated developing the response model with data mining techniques such as CBR, neural networks and support vector machines. And CBR is one of the most major tools in business because it is known as simple and robust to apply to the response model. However, CBR is an attractive data mining technique for data mining applications in business even though it hasn't shown high performance compared to other machine learning techniques. Thus many studies have tried to improve CBR and utilized in business data mining with the enhanced algorithms or the support of other techniques such as genetic algorithm, decision tree and AHP (Analytic Process Hierarchy). Ahn and Kim(2008) utilized logit, neural networks, CBR to predict that which customers would purchase the items promoted by marketing department and tried to optimized the number of k for k-nearest neighbor with genetic algorithm for the purpose of improving the performance of the integrated model. Hong and Park(2009) noted that the integrated approach with CBR for logit, neural networks, and Support Vector Machine (SVM) showed more improved prediction ability for response of customers to marketing promotion than each data mining models such as logit, neural networks, and SVM. This paper presented an approach to predict customers' response of marketing promotion with Case Based Reasoning. The proposed model was developed by applying different weights to each feature. We deployed logit model with a database including the promotion and the purchasing data of bath soap. After that, the coefficients were used to give different weights of CBR. We analyzed the performance of proposed weighted CBR based model compared to neural networks and pure CBR based model empirically and found that the proposed weighted CBR based model showed more superior performance than pure CBR model. Imbalanced data is a common problem to build data mining model to classify a class with real data such as bankruptcy prediction, intrusion detection, fraud detection, churn management, and response modeling. Imbalanced data means that the number of instance in one class is remarkably small or large compared to the number of instance in other classes. The classification model such as response modeling has a lot of trouble to recognize the pattern from data through learning because the model tends to ignore a small number of classes while classifying a large number of classes correctly. To resolve the problem caused from imbalanced data distribution, sampling method is one of the most representative approach. The sampling method could be categorized to under sampling and over sampling. However, CBR is not sensitive to data distribution because it doesn't learn from data unlike machine learning algorithm. In this study, we investigated the robustness of our proposed model while changing the ratio of response customers and nonresponse customers to the promotion program because the response customers for the suggested promotion is always a small part of nonresponse customers in the real world. We simulated the proposed model 100 times to validate the robustness with different ratio of response customers to response customers under the imbalanced data distribution. Finally, we found that our proposed CBR based model showed superior performance than compared models under the imbalanced data sets. Our study is expected to improve the performance of response model for the promotion program with CBR under imbalanced data distribution in the real world.

Comparison of Seasonal Concentration of Ammonia and Hydrogen Sulfide in Swine House according to Pig's Growth Stage (돼지 생육 단계에 따른 계절별 암모니아와 황화수소의 돈사 내 농도 비교)

  • Kim, Ki Youn;Ko, Han Jong;Kim, Hyeon Tae
    • Journal of agriculture & life science
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    • v.46 no.2
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    • pp.163-168
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    • 2012
  • The objective of this study is to quantify the levels of ammonia and hydrogen sulfide inmechanically ventilated slurry-pit swine house according to pig's growth stage and seasonal condition. Mean concentrations of ammonia and hydrogen sulfide in the housing room of gestation/farrowing pigs were 5.60 (${\pm}2.48$) ppm and 178.4 (${\pm}204.8$) ppb in spring, 2.51 (${\pm}3.08$) ppm and 86.6 (${\pm}112.5$) ppb in summer, 4.96 (${\pm}2.84$) ppm and 182.3 (${\pm}242.6$) ppb in autumn, and 6.82 (${\pm}3.42$) ppm and 206.3 (${\pm}356.8$) ppb in winter, respectively. Mean concentrations of ammonia and hydrogen sulfide in the housing room of nursery pigs were 7.18 (${\pm}3.26$) ppm and 486.0 (${\pm}190.2$) ppb in spring, 4.23 (${\pm}2.95$) ppm and 206.4 (${\pm}186.9$) ppb in summer, 7.02 (${\pm}2.65$) ppm and 465.4 (${\pm}156.8$) ppb in autumn, and 9.25 (${\pm}3.68$) ppm and 618.4 (${\pm}298.3$) ppb in winter, respectively. Mean concentrations of ammonia and hydrogen sulfide in the housing room of growing/fattening pigs were 9.26 (${\pm}3.02$) ppm and 604.4 (${\pm}186.8$) ppb in spring, 6.78 (${\pm}3.88$) ppm and 312.5 (${\pm}215.4$) ppb in summer, 9.34 (${\pm}2.14$) ppm and 578.2 (${\pm}248.1$) ppb in autumn, and 14.65 (${\pm}3.15$) ppm and 825.3 (${\pm}316.9$) ppb in winter, respectively. As a result, mean concentrations of ammonia and hydrogen sulfide in terms of pig's growth stage were highest in growing/fattening housing room followed by nursery housing room and gestation/farrowing housing room (p<0.05). The swine house showed the highest levels of ammonia and hydrogen sulfide in winter followed by spring, autumn and summer. However, there was no significant difference of ammonia and hydrogen sulfide among seasons (p>0.05).

Characteristics of the Strains Selected from Crosses between Introduced Interspecific Hybrids and Cultivars in Hibiscus Species (종간교잡 유래 도입 무궁화와 국내 선발 품종과의 교잡에 의해 육성된 계통들의 특성)

  • Kang, Ho-Chul;Ha, Yoo-Mi;Kim, Dong-Yeob;Han, In Song;Noh, Kwang-Mo
    • FLOWER RESEARCH JOURNAL
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    • v.19 no.1
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    • pp.55-63
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    • 2011
  • This study was carried out to develop new cultivars of Hibiscus species from crosses between introduced interspecific hybrids and cultivars in Hibiscus species. Fruit setting of interspecific crosses of Hibiscus strains was less than 10% and the number of seeds in the fruit was also in low level. Three individuals of specific flower and leaf characteristics were selected from crosses between introduced interspecific hybrid, 'Fujimusme'(♀), and H. syriacus 'Namwon'(♂) in 2004. A new strain, Hibiscus ${\times}$ 'W-26', was selected from the crossing of interspecific hybrid, 'Fujimusme'(♀), and H. syriacus 'Namwon'(♂), which had white flower and narrow separated petal. Hibiscus ${\times}$ 'WRB-2' was selected from the crossing of interspecific hybrid, 'Fujimusme'(♀), and H. syriacus 'Namwon'(♂), which had white flower and blue eye spot. Hibiscus ${\times}$ 'R-141' was selected from crosses between introduced interspecific hybrid, 'Shichisai'(♀) and H. syriacus 'Namwon'(♂), which had large flowers over 13 cm diameter and revealed tall tree type. Hibiscus ${\times}$ 'R-142' was selected from the crossing of interspecific hybrid, 'Shichisai'(♀), and H. syriacus 'Namwon'(♂), which had large flowers over 13 cm diameter and revealed tall tree type. The characteristics were succeded after grafting. Flower of 'R-142' had reddish violet color with red eye spot, whereas its parent had blue and purple flowers.

Application of Chlorophyll Fluorescence Parameters for the Detection of Water Stress Ranges in Grafted Watermelon Seedlings (수박접목묘의 건조스트레스 범위 탐지를 위한 엽록소형광 지수의 적용)

  • Shin, Yu Kyeong;Kim, Yong Hyeon;Lee, Jun Gu
    • Journal of Bio-Environment Control
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    • v.28 no.4
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    • pp.461-470
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    • 2019
  • This study was carried out to quantify the drought stress in grafted watermelon seedlings non-destructively by using chlorophyll fluorescence (CF) imaging technique rather than the visual judgment. Six-day old watermelon seedlings were grown under uniform irrigation for 3 days, and then given drought stress. Afterward, the sensor for the measurement of water content in plug tray cell unit was used to classify the drought-stress level into nine groups from D1 (53.0%, sufficient moisture state) to D9 (15.7%, extremely dry stress), and the 16 CF parameters were measured. In addition, re-irrigation was performed on the drought stressed seedlings(D5 - D9) to determine the growth and photosynthesis recovery level, which was not confirmed by visual judgment. The kinetic curve patterns of CF in three different drought stressed seedling groups were found to be different for the early detection of drought stress. All the 16 CF parameters decreased continuously with exposure to drought stress and drastically decreased from D5 (32.1%) where the visual judgment was possible. The fluorescence decline ratio (Rfd_Lss) started to decrease from the initial drought stress level (D5 - D6), and the Maximum PSII quantum yield (Fv/Fm) was significantly decreased in the later extreme drought stress range (D7 - D9) by re-irrigation recovery test. Thus, Rfd_Lss and Fv/Fm parameters were finally selected as potent indicators of growth and photosynthesis recovery in the initial and later stages of drought stress. Also, to the differences in the numerical values of the individual chlorophyll fluorescence parameters, the drought stress level was intuitively confirmed through the image. These results indicate that Rfd and Fv/Fm can be considered as potential CF parameters for the detection of low and extremely high drought stress, respectively. Furthermore, Fv/Fm can be considered as the best CF parameters for recovery at re-irrigation.