• Title/Summary/Keyword: $T_{50},\

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A Study on Strategic R&D Governance for Defense Sector (국방연구개발 전략 수립을 위한 R&D 거버넌스 연구)

  • Lee, Joo-Sung;Baek, Jong-Ho;Nam, Mi-Young
    • Journal of Technology Innovation
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    • v.17 no.1
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    • pp.149-177
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    • 2009
  • Today, the phase of modem war is very different from past war. That is, the winning of war depends on the ability to obtain information and high technology. The purposes of this research are to propose an effective R&D governance model in national defense sector and to present R&D strategy for obtaining core national defense technology. As a part of collaborative innovation, the strategy to exchange R&D results actively between the defense sector and the private sector will be discussed. The main contribution of this research is dearly defining the concept of R&D governance in national defense sector and applying it to an actual case. The national defense R&D governance model proposed in this paper is based on the characteristics of national defense R&D which are different from other industries. The analysis of business success factors for national defense R&D through the T-50 case study is presented in detail. The T-50 case study reveals the importance of strategic intent, core technology knowledge base, organizational structure, and project management.

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Effects of Dryness, Moisture Interruption, and Temperature on Germination of Diaporthe citri Pycnidiospores on Yuzu (건조, 습윤중단 및 온도가 유자 검은점무늬병원균 Diaporthe citri 포자 발아에 미치는 영향)

  • Hong, Sung-Jun;Yun, Sung-Chul
    • Research in Plant Disease
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    • v.24 no.2
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    • pp.132-137
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    • 2018
  • Melanose caused by Diaporthe citri is a serious disease on yuzu fruits. Moisture is the most important to infect after the pycnidiospores are released. In order to understand how dryness and moisture interruption affect on germination, the conidial suspensions on slide glass were dried for 0-48 h. For the moisture interruption experiment, moisture was supplied for 10 h then interrupted for 0-6 h depending on the treatments. Germinations on the treatments with longer than 15 h of dryness were less than 10%. And those with longer than 3 h of moisture interruption were less than 30%. Compared with other fungal phytopathogens, D. citri was xero-sensitive. Germination on yuzu feel medium was measured under 15, 20, 25, 30, $35^{\circ}C$ with 3, 6, 9, 12, 15, 18, and 24 h of wetness. The minimum wetness periods achieving 10% and 50% germinations were 4.5 and 13 h, and the optimum temperatures were $29.1^{\circ}C$ and $29.2^{\circ}C$, respectively. From the yuzu medium study, the regression equations to be required wetness period achieving 10% and 50% germinations on various temperatures were $Wh_{50%}=0.1093{\times}T^2-6.3762{\times}+106.08$ and $Wh_{10%}=0.082{\times}T^2-4.8025{\times}T+74.861$.

Comparative Study on the Committed Dose Equivalent for Adults and Infants (예탁선양치(預託線量値)에서 본 성인(成人)과 유아(幼兒)와의 비교연구(比較硏究))

  • Sung, Kye-Yong;Yook, Chong-Chul;Ha, Chung-Woo
    • Journal of Radiation Protection and Research
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    • v.9 no.2
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    • pp.76-89
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    • 1984
  • Weighted committed dose equivalents($W_T\;H_{50}$) per intake of unit activity of four nuclides-I-131, I-133, Cs-134 and Cs-137-, which was based on the concepts of ICRP Pub. 30, are calculated for adult who is 70 kg and 25 years old and, for infant who is 10 kg and 1 year old. Metabolism of iodine taken through oral or inhalation pathway is described by using the three-compartment model which consists of inorganic, thyroid and organic compartment. After intake, the amount of iodine in every compartment is calculated by solving the transfer equations among the these compartments. As soon as caesium is taken into the body, it is distributed uniformly in the body through the transfer compartment. In this case, the amount of caesium in total body is calculated by using the total body compartment model which is divided into two tissue compartments because of their different biological half-lifes of caesium in body. As a result of calculations, whether oral or inhalation pathway, the values of ($W_T\;H_{50}$) per intake of unit activity of I-131 for infants are about ten times as much as those of adults. On the other hand, for Cs-134 and Cs-137, the values of $W_T\;H_{50}$ per intake of unit activity show that, whether adults of infants, they have almost the same values.

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Characteristics of Seed Germination in Heteropappus arenarius Kitam. Native to Korea as Influenced by Temperature (온도에 따른 자생 주걱쑥부쟁이의 종자발아특성)

  • Lee, Chang-Hee;Nam, Ki-Woong
    • Korean Journal of Plant Resources
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    • v.22 no.2
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    • pp.116-122
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    • 2009
  • Heteropappus arenarius Kitam., an autumn-flowering biennial belonging to wild chrysanthemums, is found to be native in southeastern coastal area and Jeju island of Korea. It could play a good role for ground cover plants on a large-scale landscape area, especially, barren soil or sloping hillside. This study was initiated to screen optimum germination temperature influenced by local strain and harvesting stage of H. arenarius. The following was the response of seed germination between local strain and temperature. The average of final germination percentage (FG) was the highest in 'Guryongpo' (89.7%) among four local strains, followed by 'Gujwa' (87.3%), 'Gampo' (87.3%), and 'HKNU-I' (71.5%). The average of $T_{50}$ was shorter in 'Gujwa' (3.6 d) and 'Guryongpo' (4.0 d) than the others. The average of FG and $T_{50}$ was the highest as 76.2% and shortest as 3.6 d in $20^{\circ}C$, respectively, followed by $30^{\circ}C$, $25^{\circ}C$, and $15^{\circ}C$. In case of 'Gujwa', however, FG and T50 was higher in $20^{\circ}C$ and shorter in $15^{\circ}C$ than others. In the relationship between harvesting stage and temperature, the average of FG was greatly higher in Stage III (90.7%) and Stage IV (88.6%) than the others including Stage II (35.7%) and Stage I (26.0%). The average of $T_{50}$ was shorter in Stage IV (3.7 d) and Stage III (4.3 d) than the others, which showed less than 50% of FG. Nevertheless, the available range of seed harvesting stage was from Stage I to Stage IV because H. arenarius seeds could germinate at all stages. In conclusion, it was recommended that the optimum temperature and harvesting stage was $20^{\circ}C$ and Stage $III{\sim}IV$, respectively, for seed germination of H. arenarius.

A Study on the Ferroelectic and Electrooptical Properties of the Transparent Ba(LaS11/2TNbS11/2T)OS13T-PbZrOS13T-PbTiOS13T Ceramics (투광성 Ba(La1/2Nb1/2)O3-PbZrO3-PbTiO3세라믹의 강유전 및 전기광학특성에 관한 연구)

  • 김준수;류기원;박영희;박창엽
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.8
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    • pp.858-868
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    • 1992
  • 0.085Ba(LaS11/2TNbS11/2T)OS13T-0.915Pb(ZrS1yTTiS11-yT)OS13T (0.45$\leq$y$\leq$0.65) transparent electrooptic ceramics were fabricated by two-stage sintering method. The structural, ferroelectric and electrooptic properties were investigated varying composition and second sintering time. Also the possibility of application to electrooptic device was studied. If we increase the PbZrOS13T contents, dielectric constants were increased and Curie temperature was decreased. In the composition of 0.55[mol] PbZrOS13T, electromechanical coupling factor and piezoelectric charge constant were the highest values of 43[%] and 173x10S0-12T[C/N], respectively. Mechanical quality factors were decreased with the increasing PbZrOS13T contents. Light transmittance was increased with wavelength when measured from 300[nm] to 900[nm], and with PbZrOS13T contents in the range of 0.50[mol]-0.65[mol], and had the highest value of 67[%] in the composition of 0.65[mol] PbZrOS13T. From the results of ferroelectric hysteresis loop and transmitted light intensity with electric field, the specimens with compositions of 0.65,0.60,0.55[mol] PbZrOS13T were applicable to electrooptic memory device and those with compositions of 0.50,0.45[mol] PbZrOS13T were applicable to linear electrooptic device.

Mycelial Growth Properties of Domestically Collected Ectomycorrhizal Tricholoma Mushrooms in Various Culture Conditions (다양한 배양 환경에 따른 국내 수집 외생균근성 Tricholoma속 종의 균사생장 특성)

  • Kang, Jung-A;Ka, Kang-Hyeon;Kim, Jun Young;Kim, Seong Hwan
    • The Korean Journal of Mycology
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    • v.46 no.3
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    • pp.271-280
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    • 2018
  • The ectomycorrhizal basidiomycete Tricholoma is one of mushroom groups that cannot be cultivated artificially. To use this mushroom as applicable resource for food production, it is necessary to obtain information about their mycelial growth properties in various environmental conditions. This study investigated the mycelial growth of four domestic isolates of Tricholoma species (T. bakamatsutake, T. fulvocastaneum, T. matsutake, T. terreum) at different physical and chemical conditions. The optimal physical conditions for their mycelia growth were found to be a temperature range of $20{\sim}25^{\circ}C$ and a pH range of 4.0~7.0 in dark condition. The growth of T. matsutake was retarded at high temperature ($30^{\circ}C$). Tests to determine the chemical factors that affected mycelial growth showed that the four Tricholoma spp. grew 1% saline. T. matsutake grew in up to 2% saline. In the presence of various heavy metals (50 ppm) and pesticides (suppliers' recommended concentration), mycelial growth was inhibited the most by cadmium and emamectin benzoate, respectively. However, all the four Tricholoma spp. grew with $Cu^+$. The growth of T. matsutake was not inhibited by abamectin, acetamiprid, and thiacloprid. Extracellular enzyme activities of amylase and ${\beta}$-glucosidase were detected only in T. bakamatsutake and T. fulvocastaneum. The results of the present study allowed us to determine suitable or harmful environmental conditions for the mycelial cultivation of the Tricholoma spp.

EFFECT OF GLYCYRRHETINIC ACID ON CYCLOSPORIN A-INDUCED CELL ACTIVITY OF CULTURED HUMAN GINGIVAL FIBROBLATS AND MOUSE 3T3 CELLS IN VITRO (시험관 내에서 Glycyrrhetinic acid가 배양 치은 섬유모세포와 마우스 3T3 세포의 Cyclosporin A 유도 활성 세포에 미치는 영향)

  • Yoo, Soo-Kyong;Kim, Kang-Ju;Shin, Hyung-Shik;Park, Jong-Kun
    • Journal of Periodontal and Implant Science
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    • v.24 no.3
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    • pp.513-528
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    • 1994
  • 배양한 치은섬유아세포와 3T3 세포에서, glycyrrhetinic acid가 cyclosporin A를 처리 세포의 활성에 미치는 영향을 알아보기 위해서 MTT 방법을 이용하여 측정하였다. Cyclosporin A는 $1{\sim}10ng/ml$의 농도에서 인체 치은 섬유아세포와 마우스 3T3 세포 활성을 증가시켰으며, glycyrrhetinic acid는 농도와 비례하게 마우스 3T3 세포의 성장을 억제시켰다. 특히 $25{\mu}g/ml$ 이상의 농도에서는 현저하게 억제시킴을 관찰할 수 있었다. 반면, 인체 치은 섬유아세포에서는 $50{\mu}g/ml$ 이상의 농도에서 조차도 성장을 억제 시키지 않았다. 또한, 마우스 3T3와 인체 치은 섬유아세포에서 일정한 cyclosporin A 농도에 $1-100{\mu}g/ml$의 다양한 농도로 glycyrrhetinic acid를 첨가하였을 때, cyclosporin A 단독으로 처리한 세포에 비하여 유의성 있게 세포의 활성을 억제시켰으며, 특히, $100{\mu}g/ml$의 glycyrrhetinic acid를 첨가하였을 경우 세포활성을 현저하게 억제시켰다. 3T3 세포에 cyclosporin A와 $50{\mu}g/ml$의 glycyrrhetinic acid를 함께 처리한 경우 glycyrrhetinic acid단독처리한 군에 비하여 세포활성에 첨가 효과를 보였으며, 인체 치은 섬유아세포 에서는 같이 처리한 경우 glycyrrhetinic acid단독 처리에 비하여 뚜렷한 억제 효과를 나타내었다. 이러한 상승효과는 1ng/ml 의 cyclosporin A와 $50{\mu}g/ml$ glycyrrhetinic acid를 같이 처리한 군에서 가장 뚜렷하게 관찰되었다. 이러한 결과로, 인체 치은 섬유아세포에 cyclosporin A와 glycyrrhetinic acid를 동에 처리하였을 경우 세포의 활성에 상승 효과가 있음을 알 수 있다.

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ON SPACES OF WEAK* TO WEAK CONTINUOUS COMPACT OPERATORS

  • Kim, Ju Myung
    • Bulletin of the Korean Mathematical Society
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    • v.50 no.1
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    • pp.161-173
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    • 2013
  • This paper is concerned with the space $\mathcal{K}_{w^*}(X^*,Y)$ of $weak^*$ to weak continuous compact operators from the dual space $X^*$ of a Banach space X to a Banach space Y. We show that if $X^*$ or $Y^*$ has the Radon-Nikod$\acute{y}$m property, $\mathcal{C}$ is a convex subset of $\mathcal{K}_{w^*}(X^*,Y)$ with $0{\in}\mathcal{C}$ and T is a bounded linear operator from $X^*$ into Y, then $T{\in}\bar{\mathcal{C}}^{{\tau}_{\mathcal{c}}}$ if and only if $T{\in}\bar{\{S{\in}\mathcal{C}:{\parallel}S{\parallel}{\leq}{\parallel}T{\parallel}\}}^{{\tau}_{\mathcal{c}}}$, where ${\tau}_{\mathcal{c}}$ is the topology of uniform convergence on each compact subset of X, moreover, if $T{\in}\mathcal{K}_{w^*}(X^*, Y)$, here $\mathcal{C}$ need not to contain 0, then $T{\in}\bar{\mathcal{C}}^{{\tau}_{\mathcal{c}}}$ if and only if $T{\in}\bar{\mathcal{C}}$ in the topology of the operator norm. Some properties of $\mathcal{K}_{w^*}(X^*,Y)$ are presented.

Effect of Persimmon Leaves Extract on the Melanogenesis and Cell Viability in Cultured Melanoma Cells Injured by Reactive Oxygen Species (시엽추출물이 활성산소로 손상된 멜라닌세포종의 멜라닌합성 및 세포생존율에 미치는 영향)

  • Ha, Dae-Ho;Lee, Jae-Kyoo;Choi, Yu-Sun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.5
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    • pp.1304-1308
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    • 2008
  • This study was performed to evaluate the effect of persimmon leaves extract on the reactive oxygen species (ROS) in cultured melanoma cells. The B16/F10 melanoma cells were treated with various concentrations of t-butyl hydroperoxide (t-BHP). And also, the effect of persimmon leaves (PL) extract on the cytotoxicity mediated by t-BHP was done on the cell viability, tyrosinase activity and melanogenesis by colorimetric assays. In this study, t-BHP decreased cell viability in dose-dependent manner and XTT90 and XTT50 values were measured at 10 and 35 uM of PL, respectively in these culture. And also, XTT50 value was assessed as a highly toxic effect on cultured melanoma cells by the toxic criteria. In the effect of PL extract on the t-BHP-mediated cytotoxicity, PL extract significantly increased the cell viability injured by t-BHP in cultured B16/F10 melanoma cells. PL also showed the decreased tyrosinase activity and melanogenesis. From these results, it is suggested that ROS such as t-BHP showed highly toxic effect on cultured melanoma cells, and also, PL extract inhibited the tyrosinase activity and melanogenesis in cultured melanoma cells injured by ROS.

Violation Pattern Analysis for Good Manufacturing Practice for Medicine using t-SNE Based on Association Rule and Text Mining (우수 의약품 제조 기준 위반 패턴 인식을 위한 연관규칙과 텍스트 마이닝 기반 t-SNE분석)

  • Jun-O, Lee;So Young, Sohn
    • Journal of Korean Society for Quality Management
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    • v.50 no.4
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    • pp.717-734
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    • 2022
  • Purpose: The purpose of this study is to effectively detect violations that occur simultaneously against Good Manufacturing Practice, which were concealed by drug manufacturers. Methods: In this study, we present an analysis framework for analyzing regulatory violation patterns using Association Rule Mining (ARM), Text Mining, and t-distributed Stochastic Neighbor Embedding (t-SNE) to increase the effectiveness of on-site inspection. Results: A number of simultaneous violation patterns was discovered by applying Association Rule Mining to FDA's inspection data collected from October 2008 to February 2022. Among them there were 'concurrent violation patterns' derived from similar regulatory ranges of two or more regulations. These patterns do not help to predict violations that simultaneously appear but belong to different regulations. Those unnecessary patterns were excluded by applying t-SNE based on text-mining. Conclusion: Our proposed approach enables the recognition of simultaneous violation patterns during the on-site inspection. It is expected to decrease the detection time by increasing the likelihood of finding intentionally concealed violations.