• 한국작물학회지
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• 제47권4호
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• pp.292-296
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• 2002

Soybean seeds were treated with blue, red and far-red lights for 0, 6, 12, and 24 hours during 24-hour imbibition before culture for 6 days. The soybean sprouts raised were classified by their hypocotyl lengths; normal (＞4cm), abnormal (＜4cm) and non-germination, and their lateral roots, hypocotyl diameters and component dry weights were measured. Red light treatment and dark imbibition reduced the abnormal soybean sprouts more than far-red and blue light treatments, meaning that the former treatments produced more commercial sprouts. The lateral roots were more formed in blue light and dark imbibition than the other light treatments, but were completely blocked by any light treatment lasted during the whole imbibition. Although any light quality treatment did not influence their primary root lengths, blue light one lengthened the hypocotyl more than the others treated during the imbibition, and far-red light enlarged its diameter. Despite this morphological change, component, total or economic yield was not significantly different among the light quality treatments during the imbibition.

• 한국압력기기공학회 논문집
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• 제20권1호
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• pp.66-74
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• 2024

This study investigates the effects of temperatures and strain rates on the strength and ductility of Gr.91 (ASME Grade 91) steel which is widely being used as a heat-resistant material in Generation IV nuclear and super critical thermal power plants. The tensile behavior of modified 9Cr-1Mo (Gr.91) steel was studied for the three strain rates of 6.67×10^-5/s, 6.67×10^-4/s and 6.67×10-3/s over the temperature range from room temperature (RT) to 650℃. Experimental results showed that at specific combinations of temperatures (300~400℃) and strain rates, serrations appeared in the stress-strain curves. Concurrently, abnormal behaviors such as a plateau in yield strength and tensile strength, a minimum in ductility and negative strain rate sensitivity were observed. These phenomena were analyzed as significant characteristics of dynamic strain aging (DSA). Since this abnormal behavior in Gr.91 steel affects the material strength, it is judged that a correlation analysis between DSA and material strength should be crucial in the design and integrity evaluation of Gr. 91 steel pressure vessel and piping subjected to high-temperature loading.

• Clinical and Experimental Reproductive Medicine
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• 제15권2호
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• pp.149-155
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• 1988

To increase fertilization rate in vitro, separation of viable spermatozoa from the seminal plasma and its other components may be a useful procedure. Ejaculates from healthy men, whose semen analysis findings were normal in 19, and abnormal in 10, were filtered using the glass-wool filtration technique to yield a concentrated, viable sperm samples for IVF, and the usefulness and safety of this method were evaluated. The recovery rate of motile sperm in abnormal groups was 46.2% and 54.5% in normal group. The % motility was increased significantly compared with original sample after filtration, and the grade motility was improved, too. The sperm population with normal morphology was also increased significantly in both group. Using transmission electron microscopy, the ultrastructural integrity of acrosomal segment was examined in order to evaluate the potentially hazardous effect of glass-wool filtration to sperm head, however, sperm population with normal ultrastructure was increased compared with that of original ejaculate after separation. The filtered sperm was then processed for IVF, as the fertilizing capacity is the ultimate parameter of the sperm function. In abnormal group, the fertilization rate(41.5 %) and the ET rate per stimulated cycle were much lower than that of mormal group(69.6%). However, the cleavage rate and the number of embryos transfered per ET cycle were comparable with those of nomal group. The results suggest that the glass-wool filtration of sperm, particularly in oligo-asthenozoospsrmia, may be useful and safe method in the preparation of sperm for IVF.

• Asian-Australasian Journal of Animal Sciences
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• 제19권3호
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• pp.309-314
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• 2006

The present investigation was undertaken to study the milkability characteristics of Holstein cows. Out of 6,660 initial records 4,607 records were finally included in the analysis after deleting some records with an abnormal range of values for the traits considered. These 4,607 Holstein cows belonged to a total of 122 herds located in a province in Korea. The 'LactoCorder' instrument was used to electronically record the milkability traits at the milking parlor. A total of 19 traits were studied which were broadly classified into milk yield, milking speed, milking time and the electrical conductivity related traits. The SAS 9.1 statistical software was used to carry out analyses. The average maximum milk flow per minute was 3.21 kg/min, while the average milking speed during the main milking process (DMHG) had a mean value of 2.30 kg/min. The total milk yield was 14.14 kg, 62% of which was milked during the first three minutes of the milking. The average total milking time was 8.23 min. Among the three phases of the main milking process, the time of stable milk flow had the longest time (2.97 min) followed by the time at the decline phase (2.62 min). The average time taken to reach the plateau phase was 1.08 min, which can still be reduced further through improved managemental practices. Among milk yield traits, milk yield during the first two (MG2) and three (MG3) minutes of milking had high positive correlation with milking speed traits and negative correlations with almost all the milking time traits except time of incline in milk flow from 0.5 kg/min till the attainment of the plateau phase (tAN). Milking speed traits had negative correlations with total milking time, time at main milking process, time at plateau and with the time at decline. Since there was medium to high negative correlation between the milking speed and the time at plateau, there is a need for selection of cows which have intermediate milking speed so that it could require less milking time and also the optimum (higher and longer) plateau time. Proper pre-stimulation and avoiding over milking will help in further reducing the milking time and thus will add to the net profit of the farmer.

• 한국연초학회지
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• 제14권1호
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• pp.3-11
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• 1992

The present study examined various environmental and cultural media conditions for in vitro "rescue" of cross-fertilized ovules formed through sexual crosses between Nicotiana rustica and N. tabacum cv. BY4. The response ovules to two cultural procedures was compared; ovules were cultured either separately or left attached to the placenta. Total yield of seedlings and percent of normal seedlings were increased by culturing individual ovules separately, rather than on excised placenta. Total yield of seedlings and number of normal seedlings were produced following in vitro culture of individual fertilized ovules of N. rustica X M tabacum cv. BY4 at four days post-pollination on NN medium containing 2% sucrose. In the in vitro culture of fertilized ovules, high sucrose concentration increased the frequency of seedlings of abnormal appearance. Therefore, sucrose should be supplied to developing ovules at gradually decreased concentrations. Culture of fertilized ovules from three to eight days after pollination gave increased number of seedlings, but with delayed cultral time the number of morphologically normal seedling were decreased. Hybrids were uniform in appearance and showed vegetative heterosis but flower characteristics were generally intermediate between those of the parents. All hvbrids evaluated were self-sterile.f-sterile.

• 유통과학연구
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• 제12권5호
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• pp.61-69
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• 2014

Purpose - Many studies report that returns on hedge portfolios that eliminate particular risk types are abnormal from traditional asset pricing models' perspectives. This study examines the pervasiveness of anomalous returns conditioned on business cycle and group size. Research design, data, and methodology - Using KOSPI and KOSDAQ market data from July 1991 to December 2013, we categorize stocks into appropriately sized groups, and dichotomize our sample periods into expansion and recession periods then, we construct hedge portfolios by sorting stocks by anomaly variables and calculate their returns. Results - Four anomalies, including earnings yield, net stock issue, total asset growth, and liquidity appear pervasive across all groups for the entire sample period. However, only the hedge returns of net stock issues are significant across all group sizes during both expansion and recession. Conclusions - A net stock issue can be an appropriate proxy for expected growth of book equity for all group sizes in recessions. This finding could provide insights to investment industry participants and to researchers interested in the relationship between expected growth of book equity and business cycle risk.

• 반도체디스플레이기술학회지
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• 제21권2호
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• pp.74-84
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• 2022

As the semiconductor industry develops, the difficulty of newly required process technology becomes difficult, and the importance of production yield and product reliability increases. As an effort to minimize yield loss in the manufacturing process, interests in the process defect process for facility diagnosis and defect identification are continuously increasing. This research observed the plasma condition changes in the multi oxide/nitride layer deposition (MOLD) process, which is one of the 3D-NAND manufacturing processes through optical emission spectroscopy (OES) and monitored the result of whether the change in plasma characteristics generated in repeated deposition of oxide film and nitride film could directly affect the film. Based on these results, it was confirmed that if a change over a certain period occurs, a change in the plasma characteristics was detected. The change may affect the quality of oxide film, such as the film thickness as well as the interfacial surface roughness when the oxide and nitride thin film deposited by plasma enhenced chemical vapor deposition (PECVD) method.

• 농업과학연구
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• 제3권1호
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• pp.11-16
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• 1976

만식재배(晩植栽培)에 알맞는 묘대양식별(苗垈樣式別) 육묘일수(育苗日數)를 구명(究明)코져 유신(維新)과 조생통일(早生統一)을 공시(供試)하여 6월(月) 25일(日)에 이앙(移快)하여 본(本) 시험(試驗)을 실시(實施)하였던바 다음과 같은 결과(結果)를 얻었다. 1. 비닐보온육묘(保溫陸苗)가 비닐보온절충묘(保溫折衷苗)에 비(比)하여 분얼수(分蘖數) 및 수수(穗數)가 많았으며 육묘일수간(育苗日數間)에는 육묘일수(育苗日數)가 긴 것일수록 많았다. 2. 유신(維新)은 묘대일수감응도(苗垈日數感應度)가 작아서 묘대양식(苗垈樣式) 불구(不拘)하고 육묘일수(育苗日數) 60일(日)에서도 불시출수(不時出穗)가 없었으나 조생통일(早生統一)은 비닐보온절충묘대(保溫折衷苗垈)에서 육묘일수(育苗日數) 50일(日) 이상(以上)에서 불시출수(不時出穗)가 나타났고, 비닐보온육묘(保溫陸苗)에서는 60일(日)까지도 불시출수(不時出穗)가 나타나지 않았다. 3. 불시출수(不時出穗)가 조장(助長)되지 않는 묘대환경하(苗垈環境下)에서는 조파(早播)에 의(依)하여 출수촉진(出穩足進)의 효과(效果)가 있었으며, 기중(其中) 조생통일(早生統一)이 유신(維新)보다 현저(顯著) 하였다. 4. 주당수수(株當穗數)는 비닐보온육묘(保溫陸苗)가 비닐보온절충묘(保溫折衷苗)보다 육묘일수(育苗日數)에 관계(關係)없이 증가(增加)되었다. 5. 수량(收量)은 양(兩) 품종(品種) 공(共)히 비닐보온육묘(保溫陸苗)에서 많았으며 육묘일수간(育苗日數間)에는 비닐보온절충묘(保溫折衷苗)에서는 40일묘(日苗) 비닐보온육묘(保溫陸苗)에서는 60일묘(日苗)에서 양(兩) 품종(品種) 공(共)히 증수(增收) 되었다.

• 생물환경조절학회지
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• 제4권2호
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• pp.159-166
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• 1995

본 실험은 배수성과 통기성이 우수한 양액 재배 배지로써 perlite와 구입이 용이한 왕겨 및 훈탄의 혼합배지를 이용하여 스티로폼 성형베드 및 상자, 플라스틱 자루, 폿트 등의 재배용기의 차이와 배지의 종류에 따른 양액재배 오이의 생육 및 수량반응을 구명하고자 수행하였 다. 1. 스티로폼베드와 상자가 다른 용기보다 초장이 높게 나타났으며, 스티로폼 상자를 용기로 사용할 때 펄라이트 단용처리구가 275.5cm, 왕겨 혼합처리구가 277.0cm로 초장이 가장 높았다. 2. 엽면적은 스티로폼 성형베드와 상자가 가장 높게 나타났고, 자루재배, 폿트재배의 순으로 나타났다. 스티로폼 성형베드와 상자의 경우에는 펄라이트 단용>왕겨 혼합배지>훈탄 혼합배지의 순으로 나타났으나, 자루재배에서는 왕겨, 폿트재배에서는 왕겨 혼합배지에서 엽면적이 높게 나타났다. 3. 과실수량은 스티로폼 상자를 용기로 한 펄라이트 단용구가 2097.1g으로 가장 많았으며 과수도 13.4개로 높게 나타났다. 4. 상품과율은 스티로폼 베드와 상자에서 70%이상을 나타냈으나 자루재배와 폿트재배에서는 70%이하로 나타났다. 5. 곡과율과 선세과는 자루재배에서 10%이상으로 높게 나타난 반면 스티로폼 상자에서는 낮게 나타났다.

• 한국균학회지
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• 제12권2호
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• pp.65-73
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• 1984

Fusarium moniforme의 4가지 Strain중 Strain IV가 가장 병원성(病原性)이 강(强)하면서 유묘(幼苗)를 도장시키면서 고사(枯死)시키었다. 이병주(罹病株)는 Strain에 관계없이 밀양 23호와 남풍벼는 mesocotyl를 형성하였으나 삼남벼와 진주벼는 mesocotyl를 형성하지 않았다. Mesocotyl를 형성하는 밀양 23호와 남풍벼는 포장에서 건전화(健全化)되었으나 mesocotyl를 형성하지 않는 삼남벼와 진주벼는 대부분 고사(枯死)하였다. 이병(罹病)된 부위(部位)에서 병원균(病原菌)을 분리(分離)한 결과(結果)가 Strain IV가 가장많이 분리(分離)되었으며 분리부위(分離部位)는 벼전체에서 분리(分離)되었다. 키다리병출현(病出現)은 Strain IV에 이병(罹病)된것이 가장많이 본답(本畓)에서 키다리증상(症狀)을 보였으며 주당(株當)분얼수와 수량도 Strain IV에 이병(罹病)된 것은 상당히 감소 되는 경향이었다.