• Title/Summary/Keyword: Efficiency increase

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Release Characteristics of Fission Gases with Spent Fuel Burn-up during the Voloxidation and OREOX Processes (사용후핵연료의 연소도 변화에 따른 산화 및 OREOX 공정에서 핵분열기체 방출 특성)

  • Park, Geun-Il;Cho, Kwang-Hun;Lee, Jung-Won;Park, Jang-Jin;Yang, Myung-Seung;Song, Kee-Chan
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.1
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    • pp.39-52
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    • 2007
  • Quantitative analysis on release behavior of the $^{85}Kr\;and\;^{14}C$ fission gases from the spent fuel material during the voloxidation and OREOX process has been performed. This thermal treatment step in a remote fabrication process to fabricate the dry-processed fuel from spent fuel has been used to obtain a fine powder The fractional release percent of fission gases from spent fuel materials with burn-up ranges from 27,000 MWd/tU to 65,000 MWd/tU have been evaluated by comparing the measured data with these initial inventories calculated by ORIGEN code. The release characteristics of $^{85}Kr\;and\;^{14}C$ fission gases during the voloxidation process at $500^{\circ}C$ seem to be closely linked to the degree of conversion efficiency of $UO_2\;to\;U_3O_8$ powder, and it is thus interpreted that the release from grain-boundary would be dominated during this step. The high release fraction of the fission gas from an oxidized powder during the OREOX process would be due to increase both in the gas diffusion at a temperature of $500^{\circ}C$ in a reduction step and in U atom mobility by the reduction. Therefore, it is believed that the fission gases release inventories in the OREOX step come from the inter-grain and inter-grain on $UO_2$ matrix. It is shown that the release fraction of $^{85}Kr\;and\;^{14}C$ fission gases during the voloxidation step would be increased as fuel burn-up increases, ranging from 6 to 12%, and a residual fission gas would completely be removed during the OREOX step. It seems that more effective treatment conditions for a removal of volatile fission gas are of powder formation by the oxidation in advance than the reduction of spent fuel at the higher temperature.

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Studies on LED Wavelength to Enhance Growth and Bio-active Compounds of Carrots (당근의 성장과 생리활성물질 함량을 증진시키는 LED 파장에 관한 연구)

  • Kang, Suna;Kim, Min-Jung;Kim, Bong Soo;Park, Sunmin
    • Journal of Applied Biological Chemistry
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    • v.58 no.2
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    • pp.131-137
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    • 2015
  • Commercial greenhouse plant factories are highly efficient for controlling external factors such as floods, drought, insects, air pollution etc. However, they require substantial startup & maintenance investments and experimental research to optimize production. These facilities are especially useful for urban farming where high efficiency in small spaces is required. In this study, we investigated whether light emitting diode (LED) lights with mixed dominant wavelengths (650 nm : 550 nm : 445 nm=8:1:1, 650 nm : 445 nm=6:4) can increase the growth rate and bio-active compound content of carrots in comparison to that of fluorescent light (FL). LED with mixed wavelength (650 nm : 550 nm : 445 nm=8:1:1) increased the total weight and root circumference of carrots compared to FL. However, ${\beta}$-carotene contents were not significant in LED (650 nm : 550 nm : 445 nm=8:1:1). However, LED (650 nm : 445 nm=6:4) increased the ${\beta}$-carotene (FL: 7.27, LED: 10.48 mg/g ${\beta}$-carotene dried weight). These results suggested that using LED light at the ideal wavelength, at the antithesis color of the plant, might enhance plant growth and bio-active compound contents.

Study on Low Temperature Tolerant Methane-Producing Bacteria for the Treatment of Agricultural and Livestock Wastes (농축산(農畜産) 폐기물(廢棄物) 처리(處理)를 위(爲)한 저온내성(低溫耐性) 메탄 생성균(生成菌)의 특성(特性)에 관(關)한 연구(硏究) 1. 저온조건(低溫條件)에서 시료별(試料別) 메탄 생성기작(生成機作) 연구(硏究))

  • Jung, Kwang-Yong;Kim, Jai-Joung
    • Korean Journal of Environmental Agriculture
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    • v.12 no.1
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    • pp.41-49
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    • 1993
  • The Study was conducted to develope the low temperature tolerant methane-producing bacteria(LTTB) and to increase the efficiency of anaerobic fermentation for the treatment of agricultural and livestock wastes at low temperature. The samples were collected from muddy soil, water logged sediment, organic layer and anaerobic sludge at three latitudes, $34.8{\sim}37.4\;^{\circ}N(Korea)$, $41.4\;^{\circ}N(USA)$ and $54.5{\sim}56.9\;^{\circ}N(Canada)$. They were used for determination of the methanogenesis rates for isolation and identification of the LTTB. The methanogenesis rate of smaples at low temperature were higher in the cellulose medium than methanol medium. The methanogenesis rate in the samples of subarctic region were $15{\sim}19$ moles/ml during 30 days at low temperature($8\;^{\circ}C$), whereas not detected in the samples of temperate region. The methanogenesis rate in the enrichment culture of subarctic samples were inhibited by the $40\;{\mu}g/ml$ of streptomycin + vancomycin or ampicillin + oleandomycin which were not effect to the methanogens. An inhabitation of high temperature tolerant methane producing bacteria was identified in the samples of temperate region, whereas that of the LTTB growing at $8{\sim}13^{\circ}C$ was identified in the subarctic region.

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Rewetting Strategies for the Drained Tropical Peatlands in Indonesia (인도네시아의 배수된 열대 이탄지에 대한 재습지화 전략)

  • Roh, Yujin;Kim, Seongjun;Han, Seung Hyun;Lee, Jongyeol;Son, Yowhan
    • Korean Journal of Environmental Biology
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    • v.36 no.1
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    • pp.33-42
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    • 2018
  • The tropical peatlands have been deforested and converted to agricultural and plantation areas in Indonesia. To manage water levels and increase the overall productivity of crops, canals have been constructed in tropical peatlands. The canals destructed the structure of the tropical peatlands, and increased the subsidence and fire hazard risks in the region. The Indonesian government enacted regulations and a moratorium on tropical peatlands, in order to reduce degradation. A practical method under the regulations of rewetting tropical peatlands was to permit a canal blocking. In this study, four canal blocking projects were investigated regarding their planning, construction priority, design, building material, construction, monitoring, time and costs associated with the canal blockings. In the protected areas, regulations restricted the development of the tropical peatlands areas that were noted as deeper than 3 m, and the administration stopped issuing new concessions for future work projects for this noted criteria of land use. A noted purpose of canal blockings in these areas was to effectuate the restoration of the lands in the region. The main considerations of the restoration efforts were to maintain a durability of the blockings, and to encourage the participation of the area stakeholders. In the case of a concession area, regulations were set into place to restrict clear-cutting and shifting cultivation, and to maintain groundwater level in the tropical peatland. The most significant priorities identified in the canal blocking project were the efficiency and cost-effectiveness of the project. Nevertheless, the drainage of tropical peatlands has been continued. On the basis of a literature review on regulations and rewetting methods in tropical peatlands of Indonesia, we discussed the improvements of the regulations, and adequate canal blockings to serve the function to rewet the tropical peatlands in Indonesia. Our results would help establishing an adequate direction and recommended guideline on viable rewetting methods for the restoration of drained tropical peatlands in Southeast Asia.

Net Shapes of the Model Pound net according to Added Sinker - In case of the upperward flow with fish court net - (부가중량추에 따른 모형 정치망의 형상변화 - 운동장이 湖上側인 경우 -)

  • Yun, Il-Bu;Lee, Ju-Hee;Kwon, Byeong-Guk;Yoo, Jae-Bum;Cho, Young-Bok
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.41 no.1
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    • pp.17-26
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    • 2005
  • There are several problems in the commercial pound net in the heavy tide ; the breaking and loss of net, steeply variation of net shape and decreasing of fishing efficiency, etc. In order to solve these problems, we introduced method of added sinker used to coastal cultivating cage of Japan and investigated the possibility of application to the Korean pound net. The results are obtained as follows; 1. In case of the upperward flow with fish court net, tension of the frame line was increased about 10${\sim}$25% than that of prototype according to the added sinker from 1.3gf to 5.2gf. The tension of A-type and B-type was similar to the case of the prototype, the tension of C-type and D-type was increased about 10${\sim}$15% than that of prototype. 2. The variation of deformed angle of fish court net was from 0$^{\circ}$ to 70$^{\circ}$ and that of the slope net was from 0$^{\circ}$ to 64$^{\circ}$ and that of the second bag net was from 0$^{\circ}$ to 46$^{\circ}$ and the depth of the second bag net was increased about 10% when the added sinker was changed from 1.3gf to 5.2gf. The depth of the first bag net and the second bag net were decreased about 50% than that of initial depth. 3. For the deformed angle of fish court net according to the attached point of the added sinker, A-type and B-type were decreased about 25% and 10% than the prototype, respectively. C-type was similar to the case of the prototype and D-type was increased about 15% than that of the prototype. The depth of slope net became deep in turn of A-type, B-type, C-type and D-type. For the depth of the second bag net, A-type, B-type, C-type and D-type were increased about 10${\sim}$15% than that of prototype. The depth of the slope net was changed from 0$^{\circ}$ to 63$^{\circ}$ and that of the second bag net was changed from 0${\sim}$44$^{\circ}$ according to the increase of velocity. 4. The optimal weight of added sinker was about 2.6${\sim}$3.6gf and the optimal attached point of added sinker was the case of C-type and D-type.

Growth, Body shape and Carcass cutting yield traits of Duroc and Crossbred(Duroc×Pietrain×Pietrain)pigs (두록과 교잡돈(두록×피어트레인×피어트레인)의 성장, 체형형질 및 도체 부분육 생산량 비교)

  • Kim, Young Sin;Kim, JeongA;Jeong, Yong Dae;Choi, Yo Han;Cho, Eun Seok;Chung, Hak Jae;Sa, Soo Jin;Beak, Sun Young;Hong, Joon Ki
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.7
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    • pp.255-261
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    • 2020
  • This study was undertaken to evaluate the growth, body shape and carcass cutting yield traits of Duroc (D) and crossbred (Duroc×Pietrain×Pietrain; DPP) pigs. A total of 147 D and 101 DPP pigs were used for analyzing the growth trait, whereas 16 D and 16 DPP pigs were evaluated for carcass yields. Backfat thickness (BF) and average daily feed intake (ADFI) were significantly higher in D (14.07±0.24 mm, 2,101 g) than in DPP (12.69±3.25 mm, 1,909 g) (p <0.001). Moreover, D exhibited significantly higher body shape traits including body height (BH), chest depth (CD) and chest width (CW), as compared to DPP pigs (p <0.001). No differences were observed for body length (BL) between the two strains. Analysis of the carcass cutting yield traits determined for D and DPP were in the order: ham (HM; 31.17% and 33.43%), belly (BY; 23.40% and 19.55%), and picnic shoulder (PS; 16.54% and 16.87%), respectively. Then, HM showed a difference of 2.26% P with D(31.17%) and DPP(33.43%), while BY showed a difference of 3.85% P with D(23.40%) and DPP(19.55%). Taken together, our results indicate that DPP has a better feed efficiency than D, and therefore has the potential to increase the production of low-fat pork, targeting consumers having a high preference who have opted for a healthy lifestyle. These results can be used as basic data for developing an ideal pig breed.

Combustion Characteristic Study of LNG Flame in an Oxygen Enriched Environment (산소부화 조건에 따른 LNG 연소특성 연구)

  • Kim, Hey-Suk;Shin, Mi-Soo;Jang, Dong-Soon;Lee, Dae-Geun
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.1
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    • pp.23-30
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    • 2007
  • The ultimate objective of this study is to develop oxygen-enriched combustion techniques applicable to the system of practical industrial boiler. To this end the combustion characteristics of lab-scale LNG combustor were investigated as a first step using the method of numerical simulation by analyzing the flame characteristics and pollutant emission behaviour as a function of oxygen enrichment level. Several useful conclusions could be drawn based on this study. First of all, the increase of oxygen enrichment level instead of air caused long and thin flame called laminar flame feature. This was in good agreement with experimental results appeared in open literature and explained by the effect of the decrease of turbulent mixing due to the decrease of absolute amount of oxidizer flow rate by the absence of the nitrogen species. Further, as expected, oxygen enrichment increased the flame temperatures to a significant level together with concentrations of $CO_2$ and $H_2O$ species because of the elimination of the heat sink and dilution effects by the presence of $N_2$ inert gas. However, the increased flame temperature with $O_2$ enriched air showed the high possibility of the generation of thermal $NO_x$ if nitrogen species were present. In order to remedy the problem caused by the oxygen-enriched combustion, the appropriate amount of recirculation $CO_2$ gas was desirable to enhance the turbulent mixing and thereby flame stability and further optimum determination of operational conditions were necessary. For example, the adjustment of burner with swirl angle of $30\sim45^{\circ}$ increased the combustion efficiency of LNG fuel and simultaneously dropped the $NO_x$ formation.

Effect of Hwangto, Illite, Oligosacharides, Charcoal powder and Chromium picolinate on the Growth Performance and Immunity in Eary Weaned Hanwoo Calves (한우 수송아지에 대한 황토, 일라이트, 올리고당, 활성탄 및 크롬 급여가 성장발육 및 면역기능에 미치는 영향)

  • Kang, S.W.;Cho, C.Y.;Kim, J.S.;Ahn, B.S.;Chung, H.Y.;Seo, K.H.
    • Journal of Animal Science and Technology
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    • v.44 no.5
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    • pp.531-540
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    • 2002
  • This study was conducted to examine the effect of Hwangto, Illite, and any other disease resistant materials as dietary supplements on the growth performance and immunity for growing period with 30 Hanwoo male calves weaned 75days in age. Feeding trial was conducted with 6 treatments(five heads/treatment), which were T1(Control), T2(Control + 2% Hwangto), T3(Control + 2% Illite), T4(Control + 0.04% Oligosacharides), T5(Control + 2% Charcoal powder) and T6(Control + 0.1% Chromium picolinate) for 120 days from three to seven months in age. The results obtained are summarized as follows; During the experimental period, average daily gains were 0.82 to 0.92kg, and were high in the order of T3, T6, T4, T5, T2 and T1. Especially the growth rate of calves for growing period was higher in Illite, chromium-picolinate and oligo- sacharides feeding groups than in any other groups. Average daily intakes and intake ratio to body weight of concentrates for 120days were 3.91 to 4.15kg(average 4.03kg) and 3.10 to 3.31% (average 3.21%), respectively. TDN intakes per kilogram gains were 3.20 to 3.57kg(average 3.35kg) and were smaller in the order of T5, T3, T6, T4, T2 and T1, respectively. Density of IgG in serum of calves measured by the IgG SDID Kit was 10.2 to 11.6mg/$m\ell$, and especially increase rate of IgG for experimental period was high in T3 and T5 by 6.9 and 2.8%, respectively. But incidence of disease was not found to be different by treatments. According to the above results it may be concluded that Illite is a sort of clay minerals increased the growth rate, feed efficiency and immunity of early weaned calves for growing period, but was not in unprocessed Hwangto.

A Study of the Distinctive Characteristics of Government Funded Research Institutes Engaged in Technological Cooperation with SMEs (중소기업의 기술협력에서 출연연의 차별적 특징에 관한 연구)

  • Jun, Seung-pyo;Park, Hun;Yoo, Jae Young
    • Journal of Korea Technology Innovation Society
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    • v.20 no.3
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    • pp.607-641
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    • 2017
  • Recently, there has been an increase in government-wide demand for technological cooperation between government funded research institutes (GFRIs) and small and medium-sized enterprises (SMEs), while there remain a tension between positive and negative views regarding the support given by GFRIs to encourage the technological innovation of SMEs. Although preceding studies have found that the support given by GFRIs to SMEs tends to have the effect of enhancing the technological innovation outcomes of SMEs, this study examines the question of why the agent that provides technological cooperation to SMEs should be limited to GFRIs. To answer this question, in this study, we first examined the qualitative changes in the external technological cooperation behavior of SMEs over time, from 2007 to 2014. Next, we performed cluster analysis to examine whether there were distinctive characteristics of SMEs that engage in technological cooperation with GFRIs, compared to the various other alternatives available as technological cooperation partners for SMEs. Lastly, to help us identify the characteristics of the companies that technologically cooperate with GFRIs and to facilitate the administrative or practical effort to find companies that would be strong candidates for technological cooperation with GFRIs, we used discriminant analysis to define a discriminant formula for such companies likely to engage in technological cooperation. The results of this study were as follows. First, GFRIs were the most competitive -- as demonstrated by the highest level of satisfaction, etc. - compared to the other alternatives for external technological cooperation available to SMEs. This confirmed the necessity for GFRIs to provide technological cooperation to SMEs. Secondly, the issue of whether the small and medium-sized enterprise had engaged in technological cooperation specifically with GFRIs was found not to be a very significant factor in distinguishing these companies. It was found, however, that SMEs engaged in technological cooperation were distinctive, regardless of the type of institution involved in the technological cooperation. Thirdly, SMEs that were in technological cooperation with GFRIs had the characteristics of being already active in joint research and already familiar with utilizing the systems available for governmental support. The findings of this study offers various insights relevant to establishing national R&D strategies using GFRIs and improving the efficiency of policies and administrative practices intended to help GFRIs assist SMEs.

A Study on Awareness of Automated External Defibrillator, Usage Intention and Related Educational Experience in Workers at Public Institutions (공공기관 종사자들의 자동제세동기에 대한 인식과 시행의도 및 교육경험에 관한 연구)

  • Kim, Mu-Nui;Lee, Hyeon-Ji
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.11
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    • pp.416-424
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    • 2017
  • This study was conducted to examine the awareness of workers in public institutions of automated external defibrillators, their usage intention and related educational experience in an effort to increase the efficiency of education and the rate of automated external defibrillator usage in emergency situations. The subjects in this study were 243 selected. male and female adults who worked in public institutions in Gangwon Province. A survey was conducted from June 13 to August 21, 2016. The statistical analysis was based on the frequency analysis and the $X^2$-test. There were significant differences among the public institution workers awareness of how to use an automated external defibrillator according to gender (${\chi}^2=6.32$, p<0.05) and academic credentials (${\chi}^2=5.91$, p<0.05). Additionally, there were significant differences in usage intention according to academic background (${\chi}^2=5.70$, p<0.05). The most common reason for having no intention to use an automated external defibrillator for patients with cardiac arrest was that the respondents did not know how to use it (31.5%). There were also significant differences in educational experience with automated external defibrillators according to age (${\chi}^2=6.15$, p<0.05), academic credentials (${\chi}^2=11.56$, p<0.01) and career (${\chi}^2=11.92$, p<0.01). The most common form of education that the workers received pertaining to automated external defibrillators was a combination of theoretical and practical education, which represented 55.9%. The findings of the study seem to suggest that workers in public institutions used by many people must receive compulsory standard education regarding automated external defibrillators and try to boost the revival rate of patients with cardiac arrest in real emergency situations.