• 제목/요약/키워드: On-resistances ($R_{ON}$)

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An Integrated Approach in the Pest Management in Sericulture

  • Singh, R.N.;Saratchandra, Beera
    • International Journal of Industrial Entomology and Biomaterials
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    • 제5권2호
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    • pp.141-151
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    • 2002
  • The success of sericulture industry in India is mainly attributed to the well-planned annual sericultural activity and the systematic implementation of pest preventive and control measures. The insect spectrum of silkworm and its food plants is complex and plays a major role in limiting the production of silk. Insects cause extensive damage to plant whereas predators and parasites either kill the silkworm larvae or force them to spin flimsy cocoons. Unilateral control measure against this pest is mainly based on the use of synthetic organic insecticides. Though these approaches initially paid rich dividends, the undesirable consequences soon surfaced. Insecticide induced resurgence of gall midges, leafhopper, leaf roller, secondary pest out breaks and development of pest biotypes has led to realization of Integrated Pest Management in sericulture. Various components of IPM, viz. Host plant resistance, cultural practices, biological control, chemical control and integrating them at various technological levels have been studied. Sources of host plant resistance have been identified for some of the major insect pests. High yielding mulberry variety has been propagated and their resistances towards major pests have been recorded. Cultural practices like pruning, pollarding, judicious use of nitrogen, optimum spacing and weed management have preyed to be the powerful tools in containing pests. Natural control over the pest population build- up exerted by the wide range of parasitoids, predators and pathogens has been well documented with identification of natural enemies and studies on their potential. Augmentation, through inoculation or inundative releases of parasitic arthropods, is the most direct way of increasing the numbers of these beneficials in sericulture.

남부지역 삼나무 간벌목재의 못접합특성과 할렬발생 (The Nail Jointing Properties and Checking Mechanism of Thinned Japanese Cedar (Cryptomeria japonica D. Don.) Boards Grown in Southern District)

  • 소원택
    • 한국가구학회지
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    • 제22권1호
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    • pp.18-25
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    • 2011
  • This experiment was carried out to investigate the effects of nail diameter, driving distance from end on the nail check length, and the effects of nail diameter, prehole for nail driving, and nail driving slope on the nail withdrawal resistance, by the static test of universal testing machine. The test specimen were Japanese cedar (Cryptomeria japonica D. Don.) boards grown in southern district of Korea, and the nails for test were 2.02~4.82 mm in diameter. After nail driving, the back face checks of test boards were longer than the surface checks. The optimum nail diameter without checks or loss of nail withdrawal resistance were below 10% of board width and the optimum driving distance from end of boards were ten multiple of nail diameter. The relation between nail diameter (x) and withdrawal resistance (y) was linear and the regression formulae for Japanese cedar board was y = 8.66x + 7.6 ($R^2=0.978$). As both of the prehole diameter and driving slope were increased, the withdrawal resistances were significantly decreased.

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주철금형주조용 도형재의 적용성 평가 (Evaluation on the Applicability of Refractory Coatings to Metal Mold for Cast Iron)

  • 서금희;김기영;문병문
    • 한국주조공학회지
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    • 제32권3호
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    • pp.144-149
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    • 2012
  • A series of refractory mold coatings were applied to cast iron specimens, and their resistances to wear and spalling were investigated. Tests were carried out with own made measures, and also a calculation was tried for the comparison of a part of results like spalling. Worn width by scrubbing the indenter on the coating layer increased significantly at high temperature. Temperature increasing rate across the specimen when the coating side was exposed to $1000^{\circ}C$ was in the range of $14.5{\sim}75.8^{\circ}C$/sec mm, and specimens with thicker coating layer showed lower temperature increase. Severe spalling of coated layer was observed after heating the specimen, and it was able to confirm by calculation using a commercial code.

LncRNA MALAT1 Depressed Chemo-Sensitivity of NSCLC Cells through Directly Functioning on miR-197-3p/p120 Catenin Axis

  • Yang, Tian;Li, Hong;Chen, Tianjun;Ren, Hui;Shi, Puyu;Chen, Mingwei
    • Molecules and Cells
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    • 제42권3호
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    • pp.270-283
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    • 2019
  • This study was aimed to explore if lncRNA MALAT1 would modify chemo-resistance of non-small cell lung cancer (NSCLC) cells by regulating miR-197-3p and p120 catenin (p120-ctn). Within this investigation, we totally recruited 326 lung cancer patients, and purchased 4 NSCLC cell lines of A549, H1299, SPC-A-1 and H460. Moreover, cisplatin, adriamycin, gefitinib and paclitaxel were arranged as chemotherapies, and half maximal inhibitory concentration (IC50) values were calculated to evaluate the chemo-resistance of the cells. Furthermore, mice models of NSCLC were also established to assess the impacts of MALAT1, miR-197-3p and p120-ctn on tumor growth. Our results indicated that MALAT1 and miR-197-3p were both over-expressed within NSCLC tissues and cells, when compared with normal tissues and cells (P < 0.05). The A549, H460, SPC-A-1 and SPC-A-1 displayed maximum resistances to cisplatin ($IC50=15.70{\mu}g/ml$), adriamycin ($IC50=5.58{\mu}g/ml$), gefitinib ($96.82{\mu}mol/L$) and paclitaxel (141.97 nmol/L). Over-expression of MALAT1 and miR-197-3p, or under-expression of p120-ctn were associated with promoted viability and growth of the cancer cells (P < 0.05), and they could significantly strengthen the chemo-resistance of cancer cells (P < 0.05). MALAT1 Wt or p120-ctn Wt co-transfected with miR-197-3p mimic was observed with significantly reduced luciferase activity within NSCLC cells (P < 0.05). Finally, the NSCLC mice models were observed with larger tumor size and weight under circumstances of over-expressed MALAT1 and miR-197-3p, or under-expressed p120-ctn (P < 0.05). In conclusion, MALAT1 could alter chemo-resistance of NSCLC cells by targeting miR-197-3p and regulating p120-ctn expression, which might assist in improvement of chemo-therapies for NSCLC.

THE EFFECT OF AIR BUBBLES FROM DISSOLVED GASES ON THE MEMBRANE FOULING IN THE HOLLOW FIBER SUBMERGED MEMBRANE BIO-REACTOR (SMBR)

  • Jang, Nam-Jung;Yeo, Young-Hyun;Hwang, Moon-Hyun;Vigneswaran, Saravanamuthu;Cho, Jae-Weon;Kim, In S.
    • Environmental Engineering Research
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    • 제11권2호
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    • pp.91-98
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    • 2006
  • There is a possibility of the production of the air bubbles in membrane pores due to the reduction in pressure during membrane filtration. The effect of fine air bubbles from dissolved gases on microfiltration was investigated in the submerged membrane bio-reactor (SMBR). The $R_{air}$ (air bubble resistance) was defined as the filtration resistance due to the air bubbles formed from the gasification of dissolved gases. From the results of filtration tests using pure water with changes in the dissolved oxygen concentration, the air bubbles from dissolved gases were confirmed to act as a foulant and; thus, increase the filtration resistance. The standard pore blocking and cake filtration models, SPBM and CFM, respectively, were applied to investigate the mechanism of air bubble fouling on a hollow fiber membrane. However, the application of the SPBM and CFM were limited in explaining the mechanism due to the properties of air bubble. With a simple comparison of the different filtration resistances, the $R_{air}$ portion was below 1% of the total filtration resistance during sludge filtration. Therefore, the air bubbles from dissolved gases would only be a minor foulant in the SMBR. However, under the conditions of a high gasification rate from dissolved gases, the effect of air bubble fouling should be considered in microfiltration.

확률이론(確率理論)에 기초(基礎)한 철근(鐵筋)콘크리트 강도설계규준(强度設計規準) (Probability-Based USD Code for Reinforced Concrete)

  • 조효남;장동일;신재철
    • 대한토목학회논문집
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    • 제6권4호
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    • pp.53-60
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    • 1986
  • 현행(現行) 재래식(在來式) 철근(鐵筋)콘크리트 표준시방서(標準示方書)의 강도설계규준(强度設計規準)을 대치(代置)할 수 있는 AFOSM 신뢰성(信賴性) 이론(理論)에 의한 LRFD 신뢰성(信賴性) 설계규준(計規準)을 제안(提案)하는 것이 본(本) 연구(硏究) 주요내용(主要內容)이다. 우리의 현실(現實)을 고려한 각(各) R.C. 구조요소별(構造要素別) 저항(抵抗) 및 하중효과(荷重効果)의 불확실량(不確實量)을 사용하여 현행(現行) R.C. 표준시방서(標準示方書)의 신뢰성(信賴性) 수준(水準)을 검정(檢定)하므로서 우리 실정(實情)에 맞는 합리적(合理的)인 목표신뢰성지수(目標信賴性指數)를 선택한 다음, 확률변수(確率變數)의 비정규분포(非正規分布)를 등가(等價)의 정규분포(正規分布)로 변환(變換)시킨 Rackwitz-Fiessler의 실용적(實用的) 알고리즘을 이용한 AFOSM 법(法)에 의해 계산(計算)된 하중조합별(荷重組合別) 하중(荷重) 및 저항계수(抵抗係數)로부터 합리적(合理的)인 공통(共通) 하중계수(荷重係數)를 선정하고 이에 대응(對應)하는 각(各) 요소별(要素別) 저항계수(抵抗係數)를 산정(算定)하므로서 LRFD 설계규준(設計規準)을 제안(提案)하였다. 본(本) 연구(硏究)에서 제안(提案)하는 R.C. 구조(構造)의 LRFD 신뢰성(信賴性) 설계규준(設計規準)을 현행(現行) R.C. 표준시방서(標準示方書)의 강도설계규준(强度設計規準)에 대응(對應)하는 설계규준(設計規準)으로 도입(導入)함이 바람직하다는 사실(事實)을 확인할 수 있었다.

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부하변동에 의한 지중유효열전도도와 보어홀 전열저항 해석 (Analysis of Effective Soil Thermal Conductivities and Borehole Thermal Resistances with a Power Supply Regulation)

  • 노정근;연광석;송헌
    • 한국태양에너지학회 논문집
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    • 제31권4호
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    • pp.80-86
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    • 2011
  • Investigation of the effective soil thermal conductivity(k) is the first step in designing the ground loop heat exchanger(borehole) of a geothermal heat pump system. Another important factor is the borehole thermal resistance($R_b$). Thermal response tests offer a good method to determine the ground thermal properties for the total heat transport in the ground. This is done by supplying a constant heat power into a borehole heat exchanger. There are two methods to supply a constant heat power. One is to employ the electricity provided by Korea Electric Power Corporation(KEPCO). The other is to use electricity generated by a generator. In this study, the power supply regulation was found to reduce when the electricity generated by the generator was used. This is because the generator evaluated with the power supply characteristically reduces the power supply regulation between an overload and a complex using. But it sometimes occurs a power supply regulation in In-situ thermal response test. In this case getting of k,$R_b$ requires delay times and restored normal state. However, the effect of the delay times and restored normal state on the soil thermal conductivity and borehole thermal resistance is very small. Therefore it is possible to use a generally accepted delay times and restored normal state in the analysis. In this work, it is also shown that an acceptable range of ${\Delta}k$, ${\Delta}R_b$ for normal state and regulation state might be approximately 0.01-0.16W/m k, and -0.004-0.007m K/W, respectively. Thus, restored normal state of power supply regulation is valuable to recommend.

신축 전자패키지 배선용 금속박막의 신축변형-저항 특성 II. Au, Pt 및 Cu 박막의 특성 비교 (Stretchable Deformation-Resistance Characteristics of Metal Thin Films for Stretchable Interconnect Applications II. Characteristics Comparison for Au, Pt, and Cu Thin Films)

  • 박동현;오태성
    • 마이크로전자및패키징학회지
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    • 제24권3호
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    • pp.19-26
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    • 2017
  • Polydimethylsiloxane (PDMS) 기판과 금속박막 사이의 중간층으로 parylene F를 사용한 신축패키지 구조에서 Au, Pt, Cu 박막의 신축변형에 따른 저항변화를 분석하였다. Parylene F 중간층을 코팅한 PDMS 기판에 스퍼터링한 150 nm 두께의 Au 박막과 Pt 박막은 각기 $1.56{\Omega}$$5.53{\Omega}$의 초기저항을 나타내었으며, 30% 인장변형률에서 각 박막의 저항증가비 ${\Delta}R/R_o$은 각기 7 및 18로 측정되었다. Cu 박막은 $18.71{\Omega}$의 높은 초기저항을 나타내었으며 인장변형에 따라 저항이 급격히 증가하다 5% 인장변형률에서 open 되어, Au 박막과 Pt 박막에 비해 매우 열등한 신축 특성을 나타내었다.

현지 측정에 의한 남한지역의 지중유효열전도도, 보어홀 전열저항 및 초기온도 분석 (Analysis of Soil Thermal Conductivities, Borehole Thermal Resistances and Initial Soil Temperature with In-Situ Testing in South Korea)

  • 노정근;연광석;송헌
    • 한국태양에너지학회 논문집
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    • 제32권5호
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    • pp.68-74
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    • 2012
  • Investigation of the effective soil thermal conductivity($k$) is the first step in designing the ground loop heat exchanger(borehole) of a geothermal heat pump system. Another important factor is the borehole thermal resistance($R_b$). Thermal response tests offer a good method to determine the ground thermal properties for the total heat transport in the ground. The first step is measured for initial soil temperature. This is done by supplying a only pump power into a borehole heat exchanger. They need to supply into water unload heat power more than 30 minutes. In this study, the initial soil temperature was found to analysis $14.1{\sim}16.0^{\circ}C$,the ratio was 68.7% represented. In this case of $k$, was 2.1~3.0 $W/m{\cdot}k$, $R_b$ was 0.11~0.20 $m{\cdot}K/W$. In this work, it is also shown that the distribution of a soil thermal conductivity and borehole thermal resistance were on the influence of initial soil temperature. And soil thermal conductivity was related with factors of equation by linear least square method, borehole thermal resistance was on the influence of composite factors.

Frequency and Type of Disputed rpoB Mutations in Mycobacterium tuberculosis Isolates from South Korea

  • Jo, Kyung-Wook;Lee, Soyeon;Kang, Mi Ran;Sung, Heungsup;Kim, Mi-Na;Shim, Tae Sun
    • Tuberculosis and Respiratory Diseases
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    • 제80권3호
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    • pp.270-276
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    • 2017
  • Background: A disputed rpoB mutation is a specific type of rpoB mutation that can cause low-level resistances to rifampin (RIF). Here, we aimed to assess the frequency and types of disputed rpoB mutations in Mycobacterium tuberculosis isolates from South Korea. Methods: Between August 2009 and December 2015, 130 patients exhibited RIF resistance on the MTBDRplus assay at Asan Medical Center. Among these cases, we identified the strains with disputed rpoB mutation by rpoB sequencing analysis, as well as among the M. tuberculosis strains from the International Tuberculosis Research Center (ITRC). Results: Among our cases, disputed rpoB mutations led to RIF resistance in at least 6.9% (9/130) of the strains that also exhibited RIF resistance on the MTBDRplus assay. Moreover, at the ITRC, sequencing of the rpoB gene of 170 strains with the rpoB mutation indicated that 23 strains (13.5%) had the disputed mutations. By combining the findings from the 32 strains from our center and the ITRC, we identified the type of disputed rpoB mutation as follows: CTG511CCG (L511P, n=8), GAC516TAC (D516Y, n=8), CTG533CCG (L533P, n=8), CAC526CTC (H526L, n=4), CAC526AAC (H526N, n=3), and ATG515GTG (M515V, n=1). Conclusion: Disputed rpoB mutations do not seem to be rare among the strains exhibiting RIF resistance in South Korea.