• 한국작물학회지
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• 제34권2호
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• pp.113-119
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• 1989

옥수수, 수수, 수수-수단그라스, 진주조 등 경지사료작물의 simazine과 alachlor에 대한 저항성과 제초효과를 알기 위하여 1988년 봄에 포장시험, 여름과 가을에 pot 시험을 하였다. 공시품종은 옥수수 진주옥, 수수는 Pioneer(P) 931, P947, P956, 수수-수단그라스는 P855F, P988, 진주조는 수원 1호, 수원 6호이었고 시험에 따라 알맞은 품종을 선택하였다. 제초제는 봄의 포장시험과 여름 pot히험은 simazine 수화제(50% ai, g/10a): alachlor 유제(43.7% ai, ml/10a)를 제품량으로 130:0, 100:0, 70:200, 0:300, 0:400의 비율로 처리하였고, 가을 pot 시험은 수수 P 931에 alachlor를 0, 50, 100, 200, 300, 400ml/10a과 simazine : alachlor를 70(g/10a) : 200(ml/10a)으로 처리하였다. 1. 옥수수는 포장시험과 여름 pot 시험에서 모두 simazine과 alachlor에 의하여 출아률, 입묘률, 유묘의 초장과 건물종, 간장, 건물수량 등에 영향을 받지 않았다. 2. 수수와 수수-수단그라스는 포장시험에서 simazine과 alachlor에 의해 유묘의 생육과 건물수량이 영향을 받지 않았다. Simazine은 여름 pot 시험에서 출아률과 유묘의 생존률에는 영향이 없었으나 초장과 건물종은 감소시켰다. Alachlor는 여름 pot시험에서 출아률은 약간 감소시켰지만 유묘의 생존률, 초장, 건물종을 현저히 감소시켰다. 가을 pot 시험에서 alachlor는 수수의 출아률에는 영향을 미치지 않았으나 100ml/10a 이상에서는 약량이 증가할수록 유묘의 생존률, 초장, 건물종이 감소하였으나 여름보다 생육이 덜 억제되었다. 3. 진주조는 봄의 포장시험에서는 simazine에 의하여 입묘률, 간장, 건물수량에 영향을 받지 않았지만 여름 pot 시험에서는 유묘의 생존률, 초장, 건물종이 다소 감소되었다. Alachlor는 포장에서 입묘률을 감소시켜 수량이 감소하였고, 여름 pot 시험에서는 출아률은 다소 감소하였으나 출아한 개체는 하나도 생존하지 않았다. 4. Simazine은 바랭이, 강아지풀, 피 등 화본두잡초에는 효과가 적었으나 광엽잡초는 방제하였고, alachlor는 화본두 잡초와 쇠비름, 비름 등 광엽잡초는 방제하였으나 깨풀과 명아주는 방제되지 않았다. 수확기의 잡초 잔초량은 simazine과 alachlor의 혼합처리에서 가장 적었으며, 작물의 건물수량이 많으면 잔초량은 적었다.

• 식물병과 농업
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• 제5권1호
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• pp.8-13
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• 1999

Twenty two different disease on strawberry have been reported in Korea. Their occurrence patterns were depended on the varieties cultivated. Fusarium wilt occurred seriously on var. Hokowase, a variety used for the fields or semi-forcing culture. In recent years, however, anthracnose occurred remarkably as the acreage of forcing culture increases. Consequently, anthracnose reduced the stand rate and yield of the strawberry. Average occurrence rate of anthracnose was 36.9% on major strawberry cropping areas. Nyoho and Akihime, which are popular varieties for the forcing culture, are considered to be susceptible, but Holiwase and Suhong are resistant against this disease. Colletotrichum gloeosporioides and Glomerella cingulata have been reported as casual agents for this disease in Korea. C. gloeosporoides was recently reported, but C. fragariae, known to be a strong pathogen in foreign countries, has bot been found yet in Korea. These two fungal pathogens showed significant differences in some characteristics such as major infection parts of plant and responses to temperatures as well as benomyl resistance. In addition, C. gloeosporioides is more pathogenic than G. cingulata. Because vinly sheltering is effective for control of anthracnose to protect water disposal of the pathogen during the seedling stages, it is strongly recommend to use this method in conjunction with integrated control programs.

• 동력기계공학회지
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• 제11권3호
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• pp.22-28
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• 2007

Liquefied gas vaporizer is a machine to vaporize liquefied gas such as liquid nitrogen($LN_{2}$), liquefied natural gas(LNG), liquid oxygen($LO_{2}$) etc. For the air type vaporizer, the frozen dew is created by temperature drop (below 273 K) on vaporizer surface. The layer of ice make a contractions on vaporizer. The structure analysis on the heat transfer was studied to see the effect of geometric parameters of the vaporizer, which are length 1000 mm of various type vaporizer. Structure analysis result such as temperature variation, thermal stress and thermal strain have high efficiency of heat emission as increase of thermal conductivity. As the result, Frist, With-fin model shows high temperature distribution better than without-fin on the temperature analysis. Second, Without-fin model shows double contractions better then with-fin model under the super low temperature load on the thermal strain analysis. Third, Vaporizer fin can be apply not only heat exchange but also a stiffener of structure. Finally, we confirm that All model vaporizer can be stand for sudden load change because of compressive yield stress shows within 280 MPa on thermal stress analysis.

• Advances in concrete construction
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• 제8권4호
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• pp.277-283
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• 2019

In evaluating explosion-protection capacity, safety distance is broadly accepted as the distance at which detonation of a given explosive causes acceptable structural damage. Safety distance can be calculated based on structural response under blast loading and damage criteria. For the applicability of the safety distance, the minimum required stand-off distance should be given when the explosive size is assumed. However, because of the nature of structures, structural details and material characteristics differ, which requires sensitivity analysis of the safety distance. This study examines the safety-distance sensitivity from structural and material property variations. For the safety-distance calculation, a blast analysis module based on the Kingery and Bulmash formula, a structural response module based on a Single Degree of Freedom model, and damage criteria based on a support rotation angle were prepared. Sensitivity analysis was conducted for the Reinforced Concrete one-way slab with different thicknesses, reinforcement ratios, reinforcement yield strengths, and concrete compressive strengths. It was shown that slab thickness has the most significant influence on both inertial force and flexure resistance, but the compressive strength of the concrete is not relevant.

• 한국식물병리학회지
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• 제14권6호
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• pp.654-660
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• 1998

Colletotrichum gloeosporioides and Glomerella cingulata are the most important pathogens causing anthracnose which may reduce the stand rate and yield on wide kinds of plants including strawberry. Average occurrence rate of anthracnose is 36.9% on major strawberry cropping areas in Korea. We newly found that C. gloeosporioides which does not forming a sexual stage, infects strawberry and differs in some characteristics concerning virulence, cultural and morphological properties to G. cingulata which has a sexual stage. C. gloeosporioides was mainly isolated from the crown with 35.2% rate, while G. cingulata was largely isolated from petiole, runner with 40.9% rate in infected strawberry plants. These two pathogens showed significant differences in cultural characteristics such as perfect stage formation, temperature response as well as benomyl resistance. It was demonstrated that C. gloeosporioides has significantly stronger pathogenicity than G. cingulata in pathogenicity test carried on strawberry plants to various strawberry cultivars. Akihime, Akaneko and Nyoho forcing cultured strawberry cultivars, considered to be susceptible, while semiforcing cultured cultivars, such as Suhong and Holowase, were shown resistant to both pathogens. In non-wound inoculation, C. gloeosporioides was shown pathogenicity on the apple fruit, but G. cingulata could not infect it.

• 소성∙가공
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• 제25권4호
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• pp.235-241
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• 2016

Dimensional accuracy of hot coil is improved by precise control of thickness profiles, flatness, width and winding profile. Especially, precise width control is important because yield could be increased significantly. Precise width control can be improved by predicting the amount of width spread. The purpose of this study is to develop the advanced prediction model for width spread in hot finish rolling for controlling width precisely. FE-simulations were performed to investigate the effect of process variables on width spread such as reduction ratio, forward and backward tension and initial width at each stand. From the statistical analysis of simulated data, advanced model was developed based on the existing models for strip width spread. The experimental hot rolling trials showed that newly developed model provided fairly accurate predictions on the strip width spread during the whole hot finishing rolling process.

• Journal of Microbiology and Biotechnology
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• 제22권5호
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• pp.585-591
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• 2012

The antagonistic effect of Trichoderma harzianum on a range of seed-borne fungal pathogens of wheat (viz. Fusarium graminearum, Bipolaris sorokiniana, Aspergillus spp., and Penicillium spp.) was assessed. The potential of T. harzianum as a biocontrol agent was tested in vitro and under field conditions. Coculture of the pathogens and Trichoderma under laboratory conditions clearly showed dominance of T. harzianum. Under natural conditions, biocontrol effects were also obtained against the test fungi. One month after sowing, field emergence (plant stand) was increased by 15.93% over that obtained with the control treatment, and seedling infection was reduced significantly. Leaf blight severity was decreased from 22 to 11 at the heading stage, 35 to 31 at the flowering stage, and 86 to 74 at the grain filling stage. At harvest, the number of tillers per plant was increased by 50%, the yield was increased by 31.58%, and the 1,000-seed weight was increased by 21%.

• 전자공학회논문지A
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• 제33A권4호
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• pp.152-161
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• 1996

In tis work, a three-stage pipelined A/D converter (ADC) was implemented to obtain 10-bit resolution at a conversion rate of 20 msamples/s for video applications. The ADC consists of three identical stages employing a mid-rise coding technique. The interstage errors such as offsets and clock feedthrough are digitally corrected in digitral logic by one overlapped bit between stages. The proposed ADC is optimized by adopting a unit-capacitor array architecture in the MDAC to improve the differential nonlinearity and the yield. Reduced power dissipation has been achieve dby using low-power latched comparators. The prototype was fabricated in a 0.8$\mu$m p-well CMOS technology. The ADC dissipates 160 mW at a 20 MHz clock rate with a 5 V single supply voltage and occupies a die area of 7 mm$^{2}$(2.7 mm $\times$ 2.6mm) including bonding pads and stand-alone internal bias circuit. The typical differential and integral nonlinarities of the prototype are less than $\pm$ 0.6 LSB and $\pm$ 1 LSB, respectively.

• The Korean Journal of Ecology
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• 제9권3호
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• pp.123-133
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• 1986

Black pine, Pinus thumbergii, stands in southwestern Korea were investigated. The black pine forest with 90 percent or more in the relative basal area (black pine basal area/whole pine basal area, RBA) was found in the coastal area. However, from the coastal area to the inland. RBA of the pine was decreased because the competition with red pine (P. densiflora) and/or pitch pine (P. rigida). In 25 year-old plants at the coastal areas, the wood volume of black pine is twofold or more than that of red pine, fourfold or more than that of pitch pine. The optimum rotation period for the maximum yield of black pine is estimated to take 35 years, based on the site index calculated. The optimal temperature for the pine plantation in Korean peninula should be the area in over 105。C.month in warmth index. And the soil conditions with 50% of RBA or over were 0.025%~0.151% of soil salinity, 3~6% of organic matter content, pH value 4.50~5.04, 8.5~11.0 me/100g of C.E.C..

• 농업과학연구
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• 제33권2호
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• pp.123-127
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• 2006

토양 조건에 따른 찰옥수수를 재배시험 한 결과 배수가 불량한 논토양이나 밭토양 보다는 배수가 양호한 논토양이 옥수수의 생육도 다소 좋은 편이었으며 수량적인 측면에서 보면 배수가 양호한 논토양에 재배한 찰옥수수의 생체수량이 804kg/10a로 배수가 불량한 토양에서는 498kg/10a이나 밭토양에서 재배하였을 경우인 751kg/10a 보다 수량이 많았음을 알 수 있었고, 옥수수의 논 재배시 가장 많이 발생한 주요잡초의 초종은 여귀, 깨풀, 피 등이었고 특히 배수가 양호한 토양보다는 불량한 논토양에서 옥수수를 재배할 때 잡초의 발생이 많아 토양의 물리성이 잡초의 발생 및 옥수수의 생육에 영향을 주는 것으로 나타났다. 발생한 잡초의 형태적 특성별로 보면 논토양에서는 광엽 잡초, 화본과 잡초 순으로 나타났고 밭토양에서는 화본과 잡초가 주로 많이 발생하였다. 옥수수의 논 재배시 잇점으로는 잡초의 발생이 밭재배보다 작았고 논토양이 옥수수 재배에 알맞은 토양수분을 지니고 있어서 지속적으로 옥수수의 생육에 필요한 수분을 충분히 지속적인 공급으로 수량이 높았고 논토양 중에서도 특히 배수가 잘되는 논토양이 밭토양에서 재배하는 것보다도 잡초방제 및 수량적인 측면에서 유리한 것으로 보인다. 또한 기타 품질적인 면에서 이들 간에 어떤 영향을 주는지는 많은 연구와 검토가 필요하리라 본다.