• 월간 기계설비
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• s.227
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• pp.40-49
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• 2009

해양에너지는 해양의 조수 파도 해류 온도차 등을 변환시켜 전기 또는 열을 생산하는 기술로서 전기를 생산하는 방식은 조력 파력 조류 온도차 발전 등이 있다. 해양에너지는 타 신재생에너지에 비해 부존량이 풍부하고 에너지 밀도가 높으며 대규모 개발이 가능하다는 장점을 가지고 있다. 특히 조력과 조류발전은 발전량의 정확한 장기예측이 가능해 전력계통망 운영에 유리하다는 큰 장점이 있다. 그러나 전 세계적으로 해양에너지의 보급은 미미한 실정이다. 화석에너지에 비해 경제성이 낮기 때문이다. 특히 조력발전은 막대한 초기건설비가 소요되고 입지가 제한적이다. 하지만 전문가들은 에너지자원 빈국인 우리나라의 경우 해양에너지 산업화가 시기적인 문제만 있을 뿐 향후 이에 따른 건설 및 서비스 시장도 확대될 것으로 전망하고 있다. 조력 조류발전의 경우 대규모 건설공사가 수반되며 이로 인한 산업적 파급효과는 막대할 것으로 예상되고 있다. 국내의 경우 시화호 조력발전소, 가로림 조력발전소, 울돌목 조류발전소의 경우 각각 약 3,600억원, 약 1조원, 약 2,500억원 총 건설비가 소요될 것으로 전망되고 있다. 이중 토목건설 부분이 약 50%, 기계 전기 부분이 약 50%를 차지한다. 이는 향후 5년간 약 1조 6,000억원 정도의 토목건설과 기계 전기 설비시장이 새롭게 형성될 수 있다는 것을 의미한다. 이번 호에는 해양에너지 중 가장 집중적으로 추진되고 있는 조력 조류발전에 대해 알아본다.

• Ceramist
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• v.23 no.1
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• pp.16-26
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• 2020

Recently, polymer-metal composite (IPMC)-based ionic artificial muscle has been drawing a huge attention for its excellent soft actuator performance having outstanding soft actuator performance with efficient conversion of electrical energy to mechanical energy under low working voltage. In addition, light, flexible and soft nature of IPMC and high bending strain response enabled development of versatile sensor application in association with soft actuator. In this paper, current issues of IPMC were discussed including standardizing preparation steps, relaxation under DC bias, inhibiting solvent evaporation, and improving poor output force. Solutions for these drawbacks of IPMC have recently been suggested in recent studies. After following explanation of the IPMC working mechanism, we investigate the main factors that affect the operating performance of the IPMC. Then, we reviewed the optimized IPMC actuator fabrication conditions especially for the preparation process, additive selection for a thicker membrane, water content, solvent substitutes, encapsulation, etc. Lastly, we considered the pros and cons of IPMCs for sensor application in a theoretical and experimental point of view. The strategies discussed in this paper to overcome such deficiencies of IPMCs are highly expected to provide a scope for IPMC utilization in soft robotics application.

• Herbal Formula Science
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• v.28 no.3
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• pp.243-254
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• 2020

Objectives : Network pharmacology analysis is commonly used to investigate the synergies and potential mechanisms of multiple compounds by analyzing complex, multi-layered networks. We used TCMSP and BATMAN-TCM databases to compare results of network pharmacological analysis between White Ginseng(WG) and Red Ginseng(RG). Methods : WG and RG were compared with components and their target molecules using TCMSP database, and compound-target-pathway/disease networks were compared using BATMAN-TCM database. Results : Through TCMSP, 104 kinds of target molecules were derived from WG and 38 kinds were derived from RG. Using the BATMAN-TCM database, target pathways and diseases were screened, and more target pathways and diseases were screened compared to RG due to the high composition of WG ingredients. Analysis of component-target-pathway/disease network using network analysis tools provided by BATMAN-TCM showed that WG formed more networks than RG. Conclusions : Network pharmacology analysis can be effectively performed using various databases used in system biology research, and although the materials that have been reported in the past can be used efficiently for research on diseases related to targets, the results are unreliable if prior studies are focused on limited or narrow research areas.

• Food Science of Animal Resources
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• v.22 no.1
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• pp.1-7
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• 2002

Changes of the fatty acid, amino acids and collagen contents in domestic broiler chickens of different marketing standard range from 5ho to 16ho were assessed. There were no significant trend in total ratios of saturated fatty acids and unsaturated fatty acids between breast samples taken from chicken in different weight ranges. The n6 fatty acids/n3 fatty acids decreased as weight ranges decreased and the ratio was decreased down to 5:1. Eicosapentaenoic acids(EPA) were detected from chicken in 10ho and tended to increase thereafter. The contents of EPA were 0.43% in 15ho. Docosahexaenoic acid(DHA) were detected from chicken in 14ho and DHA contents of breast taken from 15ho chicken were 0.94%. The contents of glutamic acids were 2.94∼3.59% and they increased as chicken weight increased. The collagen contents were higher in thigh than breast or wings. The results from this experiments will provide a basic information for establishment of marketing standard of chicken.

• Journal of Korean Neurosurgical Society
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• v.30 no.11
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• pp.1278-1283
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• 2001

Objective : Transsphenoidal approach(TSA) has been used as useful operative method for pituitary tumor but is still controversal in case of cavernous sinus invasion or severe suprasellar extension. This study was performed to evaluate the surgical result, recurrence, effect of adjuvant treatment, especially in cases of suprasellar extension or cavernous sinus invasion. Material and Methods : We studied 56 cases of surgically treated pituitary adenoma that we were able to follow up, treated by TSA from 1993 to 1998. There were 24 cases of suprasellar extension and 11 cases of cavernous sinus invasion. The medical records and radiological findings were reviewed. Surgical results including hormonal function and recurrence rates were analyzed according to extent of tumor invasion. Mean follow-up period was 19.1 months. Results : Tumors with suprasellar extension were removed totally in 54%, whereas total tumor removal was possible only in 38% with cavernous sinus invasion. Overall of recurrence rate was 14% and recurrence rate was 25% in suprasellar extension and 9% in cavernous sinus invasion. In cases of both suprasellar extension and cavernous sinus invasion, tumors that were treated by TSA and radiation showed recurrence rate of 7%, whereas those treated by surgery alone showed 28% of recurrence. Conclusion : Transsphenoidal approach is safe and useful operative method for pituitary adenoma and adjuvant therapy including radiation therapy is effective means to decrease the recurrence in cases of suprasellar extension or cavernous sinus invasion.

• The Korea Journal of Herbology
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• v.22 no.3
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• pp.93-99
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• 2007

Objective : The present study was carried out to investigate the effects of Folium Perillae (FP) on several cytokine production such as IL-1$\beta$, TNF-$\alpha$, IL-10 and TGF-$\beta$ to determine related mechanisma in Rats. Methods: So, we investigated the effects of FP on levels of several cytokines such as IL-l$\beta$, TNF-$\alpha$, IL-10 and TGF-$\beta$ in ischemic rats. Results: In this experiment, IL-10, an immune-modulatory cytckine, level was elevated by treatment with FP, but another regulatory cytokine, TGF-$\beta$1 level was not affected. On the other hand, levels of IL-l$\beta$ and TNF-$\alpha$, an inflammatory cytokines, were lowered by treatment with FP effectively. Conclusion : In conclusion, these results suggest that FP is useful to treat patient with disease related to cerebral ischemia, because FP can elevate IL-10 level, lower IL-l$\beta$ and TNF-$\alpha$ levels.

• The Journal of Internal Korean Medicine
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• v.39 no.4
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• pp.570-591
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• 2018

Objective: This study was designed to investigate the correlation between gastric emptying measurement by ultrasonography and the findings of various questionnaires of functional dyspepsia (FD) or in Korean medicine to explore the possibility of quantification of questionnaires. Methods: Eighty-eight patients (44 patients with FD and 44 healthy controls) were recruited from October 2016 to November 2017. Gastric emptying half-time (T1/2) was measured by ultrasonography at fasting, and at 0, 15, 30, 45, 60, 90, and 120 min after meals (apple juice, 500 ml, 224 kcal). The average half-time (average T1/2) was calculated by averaging all measured half-times. A visual analogue scale (VAS), food retention questionnaire (FRQ), damum questionnaire (DQ), cold and heat questionnaire (CHQ), deficiency and excess questionnaire (DEQ), spleen-qi deficiency questionnaire (SQDQ), Nepean dyspepsia index-Korean version (NDI-K), and quality of life of NDI (NDI-QoL) were filled out by all participants. Correlation between the average T1/2 and questionnaires were analyzed for 79 patients (37 patients with FD and 42 healthy controls) after excluding missing and erroneous data. Results: The FRQ, DEQ, SQDQ, NDI-K, and NDI-QoL scores, especially for some gastrointestinal symptoms and general weakness-related symptoms, showed statistically significant correlations with average T1/2. Conclusions: Our results suggest that gastric emptying measurement by ultrasonography may be a quantitative substitute method for some Korean medical questionnaires or for some dyspepsia-related and deficiency-related items among them. However, further studies using various measurements of gastric emptying will be needed.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.171-177
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• 1986

During last 48 months, in our department 51 patients with single or multiple herniated lumbar discs have received chemonucleolysis. Forty-one of 51 cases have single level herniation and remaining cases have multiple level. Age distribution were from 19 to 59 years old. Over 4 months(longest case: 18 months) follow up revealed as follows: 40 cases(78%) revealed excellent results: 4 cases(7.8%) received discectomy 3-6 months after chemonucleolysis because of recurred symtoms : no anaphylaxis and no major complications were noted.

• Journal of Yeungnam Medical Science
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• v.11 no.2
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• pp.213-220
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• 1994

Damages on central nervous system induced by the exposure of microwave. However, the effects of microwave on ICP are not studied yet. The ICP affected by the condition of the brain has an significant effect on vital sign. So we investigated the changes of ICP of the rabbits after exposure. Twenty four rabbits were devided into 3 groups depending on the amount of exposure to microwave. One group was composed with 8 rabbits were exposed to microwave for 10 miniutes. Other were composed to microwave for 20 miniutes, 30 miniures, respectively. Intracranial pressure on each group were measured by subdural type ICP monitoring catheter immediately, first day, 3rd day, 5th day and 7th day after exposure of microwave. Results indicates that intracranial pressure of rabbits are not affected with statistical significance by exposure of microwave.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.415-422
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• 1975

This experiment was conducted to study the effect of supplementation of fowl excrement for pig feed and econmic value of using fowl excrement for pig production. 1) The gain of body weight was no significant difference between the groups at the end of experiment. 2) The amount of feed intake by the amount of fowl excrement supplementation was increasing for 20% fowl excrement added group was 3.13 and 40% fowl excrement added group was 4.10 then control group was 2.68. 3) The digestibility of concentration was decreasing by the amount of fowl excrement supplementation. 4) The analysis on the economic low income indicated that the income for 20% fowl excrement added group was 460.87 won and 40% fowl excrement added group was 985.27 won.