• Title/Summary/Keyword: Cycle characteristic

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Effects of Construction and Operation of Nuclear Power Plants on Benthic Marine Algae (원자력발전소의 건설과 가동이 저서 해조류에 미치는 영향)

  • 김영환
    • Korean Journal of Environmental Biology
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    • v.17 no.4
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    • pp.379-387
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    • 1999
  • During the past several decades, electricity generating plant increased with remarkable rapidity in Korea. Recently the increase has been much more rapid as the rate of industrialization has accelerated. Construction of nuclear power plants in coastal areas inevitably caused the perturbation of critical coastal habitats and thus influenced marine algal species composition. Particularly, an increase in the building of nuclear power plants led the amounts of heat discharged to increase exponentially. As far as the effects of cooling water and thermal discharges are concerned, benthic marine algae are likely to be vulnerable to a discharge. Heated effluents from nuclear power plants, with the temperature rises of 7~12$^{\circ}C$ under normal operating and design conditions, are discharged through the discharge canal and into natural water bodies. It is clear that the characteristic marine algal community is developed in the area affected by the thermal discharges; i.e. low species richness and low species diversity. Nevertheless, it is worthwhile to note that elevated temperatures exert differential effects depending on the algal populations. Benthic marine algae grown at the discharge canal can be regarded as warm tolerant species. 35 species (4 blue-green, 9 green, 8 brown and 14 red algae) of marine algae occurred more than 20eye frequency at discharge canal of three nuclear power plants in the east coast during 1992 ~ 1998 and thus can be categorized as warm tolerant species in Korea. To minimize the ecological impacts of waste heat on benthic marine algae, it is recommended that, in the future, nuclear power plants will have to employ some form of closed-cycle cooling for the condensers.

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An Empirical Study on the Effects of Absorption Capacity and Knowledge Protectiveness on New Product Development Performance from a Supplier Perspective (공급자 관점에서 흡수역량과 지식보호성향이 신제품개발 성과에 미치는 영향에 대한 실증적 연구)

  • Hwang, Sunil;Hur, Daesik
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.13 no.1
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    • pp.119-129
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    • 2018
  • Companies' efforts to secure and sustain a competitive advantage in the market may also appear in the form of new product development. This has increased the importance of leveraging knowledge from other companies in a global competition that is accelerating with an accelerating product life cycle and the development of transportation and communications. In order to create valuable knowledge through the exchange and combination of knowledge, the absorptive capacity of the recipient of the knowledge should be considered as important, but also the knowledge protection tendency, which is characteristic of the knowledge transferor, should be considered. However, studies that considered these factors at the same time were very limited. This study examines the effect of suppliers 'absorptive capacity and buyer' s knowledge protection on new product development performance during the joint development of new products. In addition, we investigated the interaction effect between supplier's absorption capacity and buyer's knowledge protection tendency. For this purpose, data were collected for automobile industry, electronics industry and defense industry, where joint development of new products occurred frequently, and statistical verification was performed by regression analysis. The results showed that the absorptive capacity of the supplier was positively correlated with the performance of the new product development, and the buyer 's knowledge protection tendency had a negative relationship with the new product development performance. In addition, the absorptive capacity of the supplier and the buyer 's knowledge protection tendency have an interaction effect on the new product development result. These results suggest that suppliers' absorption capacity is an important factor in the joint development of new products, but suppliers with superior absorption capacity may have a negative impact on new product development performance if buyers have a negative attitude toward knowledge transfer.

Cesium Release Behavior during the Thermal Treatment of High Bum-up Spent PWR Fuel (고연소도 경수로 사용후핵연료의 열처리에 따른 세슘 방출거동)

  • 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.53-64
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    • 2007
  • The dynamic release behavior of Cs from high burn-up spent PWR fuel was experimentally performed under the conditions of a thermal treatment process such as voloxidation and sintering conditions. In voloxidation process, influence of the oxidation and reduction atmosphere on the Cs release characteristic using fragment type of spent fuel heated up to $1,500^{\circ}C$ was compared. In sintering process, temperature history effect on Cs release behavior was evaluated using green pellet under 4% $H_2/Ar$ environment. Temperature range for complete Cs release from spent fuel fragment under voloxidation condition was about $800^{\circ}C{\sim}1,200^{\circ}C$, but that of green pellet under the reduction atmosphere was $1,100^{\circ}C{\sim}1,400^{\circ}C$. Key parameters on Cs release behavior from spent fuel was powder formation as well as the diffusion rate of Cs compound to grain boundary and fuel surface.

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The Direct Dissolution of Ion-Exchange Resin by Fenton's Reagent (펜톤시약을 이용한 이온교환수지의 직접분해)

  • Kim, Kil-Jeong;Shon, Jong-Sik;Ryu, Woo-Seog
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.1
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    • pp.85-90
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    • 2007
  • Fenton's Reagent is applied to directly dissolve the cation-exchange resin, IRN-77. The characteristics of the experimental procedure is to dry the resin first and $FeSO_4$ solution is completely absorbed into the resin, and then $H_2O_2$ is introduced later for an effective reaction between the reagents within the resin. An a characteristic of the dissolution, the lag time is needed for about 1 hour until the main reaction is occurred, which was more affected with the less concentration of $FeSO_4$ and the less initial dose of $H_2O_2$. The dose of $H_2O_2$ was equally divided into the early stage and the later stage after the initial reaction to provide an effective and safe reaction condition. The optimum conditions is appeared that the concentration of $FeSO_4$ is 0.9M and the dose of 15% $H_2O_2$ solution is 6-7 volume for the dissolution of unit weight of IRN-77. The effect of the heating on the lag time was checked and the time could be reduced within 5 minutes at $50^{\circ}C$, which is a relatively low temperature. The large amount of the resin, 5g and 10g, was also completely decomposed by increasing the dose of $H_2O_2$ to 9-10 volume ratio.

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The Direct Decomposition of Ion-Exchange Resins by Fenton's Reagent (펜톤시약에 의한 이온교환수지의 직접산화분해)

  • Kim, Kil-Jeong;Shon, Jong-Sik;Ryu, Woo-Seog
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.3
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    • pp.221-227
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    • 2007
  • Fenton's reagent is applied to directly decompose the ion-exchange resins, IRN-78 and the mixed resin with IRN-77. The newly applied procedures is to dry the resin first and the catalyst solution is completely absorbed into the resin, then a limited dose of $H_2O_2$ is introduced for an effective reaction between the reagents within the resin. As a characteristic on the decomposition of IRN-78, the resin mixture should be heated to $40^{\circ}C$ to induce the initial reaction and lag time is also needed for about 20 minutes until the main reaction occurs. The effectiveness of the decomposition is investigated using $CuSO_4,\;Cu(NO_3)_2\;and\;FeSO_4$ as a catalyst and the decomposition rate is compared depending on the concentration of each catalyst and the amount of $H_2O_2$. The most effective catalyst was found to be $FeSO_4$ for IRN-78 alone and the mixed resin with IRN-77, and $FeSO_4$ showed a special effect that the reaction was initiated without heating and a lag time. Furthermore, the optimum concentration of the catalyst for each resin and the mixed one is suggested in the view point of the amount of $H_2O_2$ needed and the stability of the decomposition reaction.

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A Study on Electrochemical Behaviors of Samarium Ions in the Molten LiCl-KCl Eutectic Using Optically Transparent Electrode (LiCl-KCl 용융염에서 광학적으로 투명한 전극을 이용한 사마륨 이온의 전기화학적 거동에 관한 연구)

  • Lee, Ae-Ri;Park, Byung Gi
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.4
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    • pp.313-320
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    • 2017
  • A spectroelectrochemical method has been applied to investigate the electrochemical behaviors and identify the kinds of samarium ions dissolved in high temperature molten LiCl-KCl eutectic. An optically transparent electrode (OTE) fabricated with a tungsten gauze as a working electrode has been used to conduct cyclic voltammetry and potential step chronoabsorptometry. Based on the reversibility of the redox reaction of $Sm^{3+}/Sm^{2+}$, which was determined from the cyclic voltammograms, the formal potential and the diffusion coefficient were calculated to be -1.99 V vs. $Cl_2/Cl^-$ and $2.53{\times}10^{-6}cm^2{\cdot}s^{-1}$, respectively. From the chronoabsorptometry results at the applied potential of -1.5 V vs. Ag/AgCl (1wt%), the characteristic peaks of absorption for samarium ions were determined to be 408.08 nm for $Sm^{3+}$ and 545.62 nm for $Sm^{2+}$. Potential step chronoabsorptometry was conducted using the anodic and the cathodic peak potentials from the voltammograms. Absorbance analysis at 545.63 nm shows that the diffusion coefficient of $Sm^{3+}$ is $2.15{\times}10^{-6}cm^2{\cdot}s^{-1}$, which is comparable to the value determined by cyclic voltammetry at the same temperature.

Housing Planning Criterion for Active Senior Generation -Focused on Baby Boomer in Seoul- (액티브 시니어 계층을 고려한 주택단지 계획기준 연구 -서울시 베이비붐 세대를 중심으로-)

  • Woo, Mi-Kyung;Park, Tae-Won
    • The Journal of the Korea Contents Association
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    • v.14 no.7
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    • pp.529-540
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    • 2014
  • Korea's baby boomers constitute a quarter of the population structure, and they are now faced with super-aged era represented by the life expectancy of 100 years. Since this generation who played a leading role in economic growth of the country has needs for active participation in society and continuous economic activities based on the healthy bodies, sufficient wealth and desires for cultural consumption, it is called 'active seniors' as a new demographic class differentiated from the conventional elder generation. This study was intended to investigate housing needs of baby boomers as preliminary seniors in Seoul with the highest residential density of the baby boomers through a bottom-up process from the perspective of consumers, and to select the findings as criteria for residential complex plans. The analysis results showed that 'social accessibility' was most highly valued among baby boomers in Seoul, and 'medical accessibility' was determined to be the second most important factor. Other items such as 'convenience of living' and 'spatial cognition' were ranked as the least important factors. These findings suggest that the life style of baby boomers in Seoul is very similar to that pursued by active seniors in terms of life cycle, and it is determined to be a characteristic as a niche for housing needs different from the one found in conventional elder generation.

Evaluation of Women with Myofascial Abdominal Syndrome Based on Traditional Chinese Medicine

  • Mitidieri, Andreia;Gurian, Maria Beatriz;Silva, Ana Paula;Tawasha, Kalil;Poli-Neto, Omero;Nogueira, Antonio;Reis, Francisco;Rosa-e-Silva, Julio
    • Journal of Pharmacopuncture
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    • v.18 no.4
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    • pp.26-31
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    • 2015
  • Objectives: This study used semiology based on traditional Chinese medicine (TCM) to investigate vital energy (Qi) behavior in women with abdominal myofascial pain syndrome (AMPS). Methods: Fifty women diagnosed with chronic pelvic pain (CPP) secondary to AMPS were evaluated by using a questionnaire based on the theories of "yin-yang," "zang-fu", and "five elements". We assessed the following aspects of the illness: symptomatology; specific location of myofascial trigger points (MTrPs); onset, cause, duration and frequency of symptoms; and patient and family history. The patients tongues, lips, skin colors, and tones of speech were examined. Patients were questioned on various aspects related to breathing, sweating, sleep quality, emotions, and preferences related to color, food, flavors, and weather or seasons. Thirst, gastrointestinal dysfunction, excreta (feces and urine), menstrual cycle, the five senses, and characteristic pain symptoms related to headache, musculoskeletal pain, abdomen, and chest were also investigated. Results: Patients were between 22 and 56 years old, and most were married (78%), possessed a elementary school (66%), and had one or two children (76%). The mean body mass index and body fat were 26.86 kg/cm2 (range: 17.7 - 39.0) and 32.4% (range: 10.7 - 45.7), respectively. A large majority of women (96%) exhibited alterations in the kidney meridian, and 98% had an altered gallbladder meridian. We observed major changes in the kidney and the gallbladder Qi meridians in 76% and 62% of patients, respectively. Five of the twelve meridians analyzed exhibited Qi patterns similar to pelvic innervation Qi and meridians, indicating that the paths of some of these meridians were directly related to innervation of the pelvic floor and abdominal region. Conclusion: The women in this study showed changes in the behavior of the energy meridians, and the paths of some of the meridians were directly related to innervation of the pelvic floor and abdominal region.

Efficient Indirect Branch Predictor Based on Data Dependence (효율적인 데이터 종속 기반의 간접 분기 예측기)

  • Paik Kyoung-Ho;Kim Eun-Sung
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.43 no.4 s.310
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    • pp.1-14
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    • 2006
  • The indirect branch instruction is a most substantial obstacle in utilizing ILP of modem high performance processors. The target address of an indirect branch has the polymorphic characteristic varied dynamically, so it is very difficult to predict the accurate target address. Therefore the performance of a processor with speculative methodology is reduced significantly due to the many execution cycle delays in occurring the misprediction. We proposed the very accurate and novel indirect branch prediction scheme so called data-dependence based prediction. The predictor results in the prediction accuracy of 98.92% using 1K entries, and. 99.95% using 8K But, all of the proposed indirect predictor including our predictor has a large hardware overhead for restoring expected target addresses as well as tags for alleviating an aliasing. Hence, we propose the scheme minimizing the hardware overhead without sacrificing the prediction accuracy. Our experiment results show that the hardware is reduced about 60% without the performance loss, and about 80% sacrificing only the performance loss of 0.1% in aspect of the tag overhead. Also, in aspect of the overhead of storing target addresses, it can save the hardware about 35% without the performance loss, and about 45% sacrificing only the performance loss of 1.11%.

Biological Characteristics of Lycorma delicatula and the Control Effects of Some Insecticides (꽃매미(Lycorma delicatula)의 생태 특성 및 약제 살충 효과)

  • Park, JI-Doo;Kim, Min-Young;Lee, Sang-Gil;Shin, Sang-Chul;Kim, Jun-Heon;Park, Il-Kwon
    • Korean journal of applied entomology
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    • v.48 no.1
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    • pp.53-57
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    • 2009
  • Biological Characteristics of Lycorma delicatula and insecticidal activity of some insecticides against nymphs of L. delicatula was investigated. Nymph of L. delicatula had 4 instars, and color of body was black. There were white spots on the body of 1st-3rd nymph. Upper body became red at 4th nymph. Adult forewings were brownish, and had black spots. Color of hind wing were red. The egg mass was covered with a yellowish brown secretion. The adult of L. delicatula emerged once a year. Among test insecticides, deltamethrin 1% EC and fenitrothion 50% EC showed very quick and strong insecticidal activity against the 2nd-3rd nymphs of L. delicatula. Imidacloprid 4% SL and clothianidin 8% SC showed 100% insecticidal activity at 24h after treatment. Thiacoprid 10% SC revealed the weakest insecticidal activity among the insecticides tested.