• Korean Journal of Agricultural Science
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• 제34권2호
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• pp.119-123
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• 2007

Germination ratio on the 300 collected genetic resources showed 80 to 100 percentage, but those of some accessions were very low as below 30 percentage. Early growth phase of most of these lines were very poor while some collected lines were very vigor. Range of stem height showed from 150 to 199cm, but that of some accessions showed below 100cm as five percentage and some of them was over 250cm as eight percentage. Number of tillers per plant appeared less one but some collected lines have two to three tillers per plant. In days to tasseling, some accessions showed more four per plant. Ear length of these accession showed above 60 percentage as 11 to 15cm, while that of some collected lines showed over 10 percentage as 16 to 20cm.

• Korean Journal of Environment and Ecology
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• 제30권3호
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• pp.423-433
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• 2016

This study compared the effect of different types of sounds(no sounds, sounds of nature, music, and sounds of children playing) on profile of mood states(POMS) in a healing forest. Data were collected from 231 respondents selected from among visitors to the 'Healing Field' in 'Jangseong Chukryongsan Pyeonbaek Healing Forest' in October, 2012. Each respondent was exposed to one type of sound. The results showed that there were differences in POMS among the different sound treatment groups. Sounds of children playing showed negative effects on POMS. Unexpectedly, however, sounds of nature and musical sounds had no effects on POMS. These tendencies were consistently found not only for total mood disturbance score (TMDS) but also for POMS by factors (i. e. tension, anger, vigor, fatigue, confusion, depression). Perceived crowding level was positively correlated with TMDS(r=0.568) and POMS by factors (range: r=0.331 - 0.571). This paper discusses the research results and suggests several managerial implications.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 한국추진공학회 2000년도 제14회 학술강연논문집
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• pp.10-10
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• 2000

램제트 엔진은 비추력이 높고 추력 레벨은 낮으므로, 2단 추진기관에 적합한 추진 시스템이다. 1단-추진기관의 작동이 끝나고, 2단 램제트 엔진이 점화 후 안정된 연소에 도달되기까지 비행체의 속도는 항력에 의하여, 초당 약 마하수 0.1 정도씩 감소된다. 1단 연소 후 2단 램제트로 전환되는 지연시간이 길수록 1단에서 요구되는 종말 가속도는 증가되므로, 1단이 차지하게되는 부피는 증가되고 비행체의 크기 또한 늘어나게 된다. 따라서 1단에서 2단 램제트로 천이되는데 소요되는 시간을 가능한 짧게 하는 것이 효과적이다. 그러나 램제트 엔진의 특성상 선결되어야할 다음과 같은 여러 문제들이 있다. 첫째, 1단 작동 시 공기 흡입구와 연소실은 차단벽으로 분리되어 있다가, 1단 연소후 차단막이 제거되어 외부공기가 램제트 연소실로 흡입된다. 흡입되는 공기는 흡입구의 형상에 의하여 램 압축되지만 초음속으로 연소실을 통과하게된다. 연료 주입 구에서 공급되는 연료는 연소실에서 유동의 흐름방향(streamline)에 따라서 연소실로 확산되는데, 연소되기 전에는 유속이 빠르게 노즐로 빠져 나가므로 램제트 연료가 재순환 구역(recirculation zone)으로 침투하는데 쉽지가 않다. 둘째, 연소실 입구에서 발생되는 와류 (ring vortex)는 1단 연료의 고온 연소 가스를 연소실로 확산시키는데, 비 균일한 온도 분포를 유발하여 램제트 연료의 점화에너지가 공급되는 시간이 적당하지 않을 경우 균일한 화염 전파에 악영향을 준다. 셋째, 연소실에서의 빠른 유동 조건은 연료가 연소실에 머무를 수 있는 시간을 감소시키며, 연소실 입구에서 강한 전단 응력이 발생되어 화염이 안정화되는데 악 영향을 미치게된다. 본 논문은 공기 흡입구, 연소실 및 노즐을 통합하여 수치해석을 하였으며 열유동/점화/연소등의 미케니즘을 이해하고, 주요 인자들 중 와류의 영향에 초점을 맞추었다.다고 판단되며 배기 가스 자체에 대기 공기중에 함유되어 있던 습기가 얼어붙는(Icing화) 문제가 발생하기 때문에 배기가스의 Icing을 방지하기 위하여 압축기 끝단에서 공기를 추출하여 배기부분에 송출할 필요성이 있는 것으로 판단되었다. 출구가스의 기체 유동속도가 매우 빠르므로 (100-l10m.sec) 이를 완화하기 위한 디퓨저의 설계가 요구된다고 판단된다. 또 연소기 후방에 물을 주입하는 경우 열교환기 및 기타 부분품에 발생할 수 있는 부식 및 열교환 효율 저하도 간과할 수 없는 문제로 파악되었다. 이러한 기술적 문제가 적절히 해결되는 경우 비활성 가스 제너레이터는 민수용으로는 대형 빌딩, 산림, 유조선 등의 화재에 매우 적절히 사용되어 질 수 있을 뿐 아니라 군사적으로도 군사작전 중 및 공군 기지의 화재 그리고 지하벙커에 설치되어 있는 고급 첨단 군사 장비 등의 화재 뿐 아니라 대간첩작전 등에 효과적으로 활용될 수 있을 것으로 판단된다.가 작으며, 본 연소관에 충전된 RDX/AP계 추진제의 경우 추진제의 습기투과에 의한 추진제 물성 변화는 미미한 것으로 나타났다.의 향상으로, 음성개선에 효과적이라고 사료되었으며, 이 방법이 편측 성대마비 환자의 효과적인 음성개선의 치료방법의 하나로 응용될 수 있으리라 생각된다..7%), 혈액투석, 식도부분절제술 및 위루술·위회장문합술을 시행한 경우가 각 1례(2.9%)씩이었다. 13) 심각한 합병증은 9례(26.5%)에서 보였는데 그중 식도협착증이 6례(17.6%), 급성신부전증 1례(2.9%), 종격동기흉과 폐염이 병발한 경우와 폐염이 각 1례(2.9%)였다. 14) 식도경 시행회수는 1회가 17례(54.8%), 2회가 9례(29.0%), 3회 이상이 5례(16.1%)였다.EX>$IC_{50}$/ 값이 210 $\mu\textrm{g}$/$m\ell$로서 효과적

• Korean Journal of Plant Resources
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• 제21권1호
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• pp.47-51
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• 2008

This study was carried out to get the basic data for safflower cultivation according to sowing date by growth analysis for 2 years form 2003 to 2004 at Institute of natural product in Uiseong, G.B.A.R.E.S.. Safflower(Cheongsoo cultivar) was seeded at March 1st, April 1st, May 1st, and July 1st in field. The necessary date for germination was 24 days, when safflower was seeded at March 1st, but it was 8 days which sowed at April 1st and when the seed was sowed at high temperature period, the necessary date for germination was getting short. The necessary date for flowering was the same trend as germination; it took 104 days at March 1st, 79 days at April 1st, 65 days at May 1st, and 58 days at July 1st sowing treatment. The safflower growth was the most vigor when it was sowed at March 1st. T/R(Top/Root) ratio was gently increased during growing season, but when the seed was sowed at July 1 st, it was low compare to sowing at March 1st and April 1st. RGR(Relative growth rate) was the highest during shoot growth stage, but it was rapidly decreased after flowering. CGR(Crop growth rate) was increased at branching stage, and the increasing velocity was slightly decreased just before flowering, and it was increased again at flowering and at this stage, CGR was the highest, and then it did not increased. NAR(Net assimilation rate) was the highest at shoot growth stage during growing season, and was the highest which was sowed at March 1st.

• Journal of Life Science
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• 제16권2호
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• pp.352-356
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• 2006

Quantity of protein, amino acid, and sugar leaked from seeds was greater as the viability of seeds was dropped by the time elapsed of seed aging treatment. In the seeds with the artificial aging treatment for 20 days, 35.8 mg of protein was leaked on the 4th day after soaking, which was 6.9 times higher than that of control. Leakage of amino acid was also higher from low quality seeds treated with the aging treatment. In the seeds with the aging treatment for 20 days, $36.5{\mu}g$ fig of sugar was leaked on the 4th day after soaking, which was 2.8 times higher than that of control. The leakage of inorganic compound was higher from the low quality seeds, and leakage of total protein, amino acid, and sugar. According to .the quantity of leakage, water soluble compounds, which can be used for the assessment of seed quality without any destruction, were protein and potassium. Germination rate and percentage of seeds were dropped with the seed aging treatment, and the seed viability could be recovered by priming treatment. This phenomenon was very clear when the low quality seeds were germinated at low temperature.

• Journal of Life Science
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• 제13권1호
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• pp.9-14
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• 2003

Seed germinability might be highly related to seedling establishment. The experiments were carried out to evaluate the effect of presowing treatments of aging, priming, $GA_3$ , prechilling and water imbibition, different temperatures and light quality during germination on germination of gourd (Lagenaria siceraria Standl.) seeds. Aging treatment with different temperatures and periods was done by the accelerated aging method. Priming using KNO$_3$ and $GA_3$ treatment for 24 hours were done at 100 mM and at 0.01 mM before a week prechilling. The germination tests using a week prechilled seeds were done at 10, 20 and $30^{\circ}C$ on the condition of darkness, and also with blue, red, far-red light and darkness as light quality treatments. FR-yongjadaemok and FR-kunghap were used as test cultivars and their daily germination rates were measured at treatment levels. Germination rates were reduced in the seeds aged at $45^{\circ}C$ for 6 days. Prechilling showed the highest and fastest rate among the four presowing treatments but the two other presowing treatments had similar or less rates than water imbibition. Prechilling done before sowing enhanced the low vigor seeds, and accelerated the germination of cv. FR-kunghap at 20 to $30^{\circ}C$ and with blue, red light or darkness during germination although far-red light inhibited their germination.

• Journal of The Korean Society of Grassland and Forage Science
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• 제26권3호
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• pp.127-132
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• 2006

This experiment was conducted to evaluate the effect of manure and chemical fertilizer on the forage yield and quality of oat at no-tillage. The experimental design was a randomized complete block design. The three treatments were: chemical fertilizer, manure fertilizer, and chemical and manure mixture. Seedling vigor was higher at chemical fertilizer than manure, but more greener at manure application than chemical fertilizer. Dry matter (DM) content of oat at manure was higher than chemical and mixture fertilizer (p<0.05). There was no difference in DM yield, TDN (total digestible nutrients) yield, and CP (crude protein) yield of oat at no-tillage system, but the fresh yield was significantly higher in chemical fertilizer compared to manure. The CP content for oat was significantly higher in manure than chemical fertilizer. However, no significant effects were observed for NDF (neutral detergent fiber), ADF (acid detergent fiber), TDN and RFV (relative feed value) in different fertilizer application. Based on the results of this study, manure don't affected forage production and quality of no-till oat except CP content because forage oat is used off-season crop.

• Journal of Korean Society of Forest Science
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• 제105권1호
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• pp.63-72
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• 2016

A study was conducted to evaluate the effect of collected region(Bongpyeong in Gangwon, 690 m, Mt. Halla in Jeju, 1,085 m), pre-treatment (stratification, soaked in distilled water or $GA_3$) and shading (control, 50%, 80%) on seed emergence and seedlings growth of Ligularia fischeri. The result showed that seed emergence (%) of L. fischeri were 6.9~75.5% (Gangwon : 6.9~32.8%, Halla : 22.2~75.5%). Maximum seed emergence (%) of 32.8 (Gangwon) and 75.5 (Halla) were achieved for seeds were stratified, soaked in distilled water, and under non-shading for L. fischeri (Gangwon), whereas seeds were stratified, soaked in $GA_3$ 100 ppm, and under 80% shading for L. fischeri (Halla). In this study, the best seedling vigor index (SVI) of L. fischeri (Gangwon) and L. fischeri (Halla) were obtained when seeds were stratified, soaked in distilled water, and under 50% shading. The survival rate of potted seedlings for L. fischeri (Halla) were 100% of all shading conditions, but there were decreased by 77.8%, 61.1%, 55.6%, as an increasing shading rate (con, 50%, 80%) for L. fischeri (Gangwon). Therefore, good seedlings were obtained when seed (Mt. Halla) of L. fischeri were stratified, soaked in distilled water, and under 50% shading, and then seedlings were transferred in pot.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제45권3호
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• pp.176-180
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• 2000

The higher sugar and lower starch in super sweet corn may be due to modified endosperm genes sh, bt series, but its seeds have major limiting factors causing low germination and low seedling vigor, This study was conducted to determine what measurable kernel characteristics during the grain tiling period might be more useful as a guide to optimize harvest date for good seed quality in hybrid super sweet corn production. Artificial crossing in super sweet corn hybrid (Chodangok 1) was made on the same day, and ears were harvested from 18 days to 53 days after pollination at weekly intervals. Kernel weight, moisture content, hardness, endosperm rate, seedling height and storage nutrients such as sugars, protein, starch, and germination rate were measured for the kernels at each harvest. Super sweet corn hybrid, Chodangok 1 presented satisfactory germination rate above 70% when harvested on 39 to 46 days after pollination. Its storage nutrients at that time were 23.7-24.2% in starch content 5.5-5.9% in total sugars, 38.9-46.6% in kernel moisture, and 62.7-64.2% in endosperm rate. Germination rate was extremely high when harvested on 39 days after pollination. The black layer of Chodangok 1 could not be used as an indicator for seed harvest. These results suggested that optimum harvest date seems to be 39 days, and kernel moisture and starch content could be used as indications of kernel maturity in deciding when to harvest fer good seed quality in super sweet corn.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제65권4호
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• pp.496-507
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• 2020

Virus infections of apples result in lowered commercial qualities such as low sugar content, weakened tree vigor, and malformed fruits. An effective way to control viruses is to produce virus-free plants based on the development of an accurate and sensitive diagnostic method. In this study, real-time PCR assays based on SYBR Green I and TaqMan probes were developed for detecting ASGV, ASPV, and ApMV viruses. These methods can detect and quantify 10³ to 10¹¹ RNA copies/μL of each virus separately. Compared with methods with two different dyes, the SYBR Green I-based method was efficient for virus detection as well as for assay using the TaqMan probe. Field tests demonstrated that real-time PCR methods developed in this study were applicable to high-throughput diagnoses for virus research and plant quarantine.