• Applied Biological Chemistry
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• 제43권2호
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• pp.124-129
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• 2000

농업유역에서 영양원소들은 시비 후 강우에 의해 지표 유출이 생기면 용해되거나 토사에 흡착된 상태로 하천에 유입되어 부영양화의 주요한 요인이 되고 있다. 농경지로부터의 영양염류 유실 정도를 평가하기 위해 경북 영천군 임고천 유역의 대표적 영농형태인 과수원 토양에 $14.3{\times}24.8\;m$면적의 유출 시험포를 설치하고 1999년 3월부터 11월 사이에 발생한 26개의 강우 사상에 대하여 지표 유출수량과 토양 유실량을 측정하였으며 이들과 함께 발생하는 질소와 인의 유실량을 조사하였다. 시험 포장에는 화학비료와 혼합유박비료로 질소와 인이 각각 112, 46kg/ha씩 처리되었다 조사 기간 동안 발생한 총 표면 유출수량은 $421.5\;m^3/ha$이었고 토양 유실량은 1,989kg/ha이었다. 유출수중의 T-N, $NO_3-N$, $NH_4-N$, T-P 및 $PO_4-P$의 농도는 각각 $4.7{\sim}171.0,\;0.1{\sim}188.0,\;0.13{\sim}3.36,\;0.58{\sim}4.99$ 및 $0.05{\sim}3.71\;mg/l$ 범위였다 강우에 의해 지표면으로 유실된 총 질소량은 16.39 kg/ha였으며 이중 질산태 질소와 암모늄태 질소가 각각 75%와 3%를 차지하였다. 인의 유실량은 총 16.39 kg/ha였으며 이 중에서 이온형태의 인이 47%였으며 토사와 함께 유실되는 인은 27% 정도였다. 질소와 인의 총 유실량은 각각 총 시비량의 9.5% 및 2.3%였다.

• 전자공학회논문지A
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• 제32A권1호
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• pp.89-96
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• 1995

Lateral p-i-n photodiodes have been fabricated, electrically tested, and incorporated into microwave control circuits such as an optically excited microwave atttenuator and reflection type phase shifter. Circuit design procedures for the loaded-line phase shifter with the optically controlled p-i-n photodiode are presented. The equal loss loading mode presented for the first time for the phase shifter circuits with lossy load allows an equal insertion loss of the phase shifter in both of its phase states. It is found that the insertion loss of the equal loss loading mode phase shifter constructed with the fabricated p-i-n photodiode load are about 3dB for 11.25$^{\circ}$ bit and 1dB for 5.625$^{\circ}$ bit for the frequency range of 2GHz to 11GHz.

• 한국토양비료학회지
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• 제49권6호
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• pp.669-676
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• 2016

A field study was conducted to determine the runoff loss of N and P in small scale of red pepper field plots (10% slope), consisting of three different plots with black polyethylene vinyl mulching (mulching), ridge without mulching (ridge), and flat without ridge and mulching (flat). Composted manure and urea as a basal application were applied at rates of $20MT\;ha^{-1}$ and $93kg\;N\;ha^{-1}$, respectively. Urea at $189kg\;N\;ha^{-1}$ and fused phosphate at $67kg\;P_2O_5\;ha^{-1}$ were additionally applied on June 25 with different fertilization methods, broadcast application in flat plot and hole injection in ridge and mulching plots. Plant uptake of N and P was positively correlated with their respective concentrations in surface soil: mulching > ridge > flat plots. The runoff loss by soil erosion was higher in flat plot than ridge and mulching plot with contour line. Nitrate loss by the runoff water had no significant differences among three surface management practices, but the higher average value in ridge and mulching plots than flat plot. Especially, the flat plot had no phosphate loss during summer season. This is probably due to low labile P content in surface soil of flat plot. In the summation of soil and water loss, flat plot was higher in N and P loss than ridge and mulching plot with contour line. Nevertheless, the nitrate and phosphate loss by runoff water could be more important for non-point source management because the water could meet the river easier than eroded soil because of re-deposition around slope land.

• Journal of Animal Science and Technology
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• 제57권5호
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• pp.20.1-20.8
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• 2015

Background: In order to prepare for the regulation about the limit of manure production, the status of manure management and the amount of nutrients in the compost discharged from Hanwoo breeding farm shall be known. This study aimed to find the practical amount of nutrients (volatile solids, VS; total nitrogen, T-N; total phosphorus, T-P) in manure, and compost samples collected from 40 Hanwoo breeding farms and the loss of the nutrients was calculated during the composting period, which supports to develop nutrient loading coefficients (NLCs) for each nutrient. Results: Although the addition of bedding materials for composting caused the increase of the VS amount before composting, the comparison of VS, N, and P amounts in between manure and compost showed the lower VS by 4 % as well as T-N and T-P amounts by 69 and 40 %, respectively, of which values were corresponded with the NLCs of 0.96, 0.31, and 0.60 for VS, N, and P, respectively, based on the questionnaire, and sample analyses. Considering with the environmental impacts including land application from Hanwoo manure, P loss should be zero before and after composting. In this regard, nitrogen loss of 50 % occurs and VS was increased by 30 %. In addition, feasible cases for the calculations based on the notification from Ministry of Environment were compared with this study. Conclusions: The development of NLCs from Hanwoo manure in this study implies that the loss of nutrients in manure occurs during the composting or storing period. The mass balances of N and P from livestock manure to land application may be overestimated over the practical values. It is necessary to build up the database about each livestock category other than Hanwoo.

• 한국수정란이식학회지
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• 제23권2호
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• pp.109-114
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• 2008

This study examined pregnancy and fetal loss rates according to different estrus synchronization protocols and injection of gonadotropin releasing hormone (GnRH) after transfer of Korean Native Cattle embryos to Holstein recipients. In Experiment 1, recipients received no treatment (Control, n = 119); two injections of prostaglandin$F_{2{\alpha}}$ ($PGF_{2{\alpha}}$ ) 11 days apart (PGF group, n = 120); GnRH (day 0)-$PGF_{2{\alpha}}$ (day 7)-GnRH (day 9) (Ovsynch group, n = 120); and CIDR (day 0)-$PGF_{2{\alpha}}$ and CIDR removal (day 7)-GnRH (day 9) (CIDR group, n = 110). In Experiment 2, the control group was received no treatment of GnRH. The treatment groups were received GnRH at embryo transfer (ET) (day 0), 7 days later, 14 days later, ET and 7 days later, 7 and 14 days later, or ET, 7 and 14 days later. Recipients were assigned to treatment randomly and received two in vitro produced blastocysts. Pregnancy was diagnosed at day 60 by palpation per rectum. Fetal loss to term was determined by palpation every 90 days thereafter. In Experiment 1, the pregnancy rate in the CIDR group (59.1%) were higher than in the Control group (42.0%) (p<0.01); fetal loss rates were similar for all groups (12.0 to 18.5%). In Experiment 2, the pregnancy rate in Day 0+7+14 group was higher (60.2%) than the control (40.2%) (p<0.01) and resulted in a lower fetal loss (p<0.05) than the control (4.6 vs. 11.4%). There were no significant difference between other treatment and the control (p>0.05). These results show that pregnancy rates of bovine embryos can be enhanced by CIDR insertion or GnRH $3{\times}$ treatment. Additionally, fetal loss may be reduced with GnRH treatment after ET.

• 한국염색가공학회지
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• 제26권4호
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• pp.331-338
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• 2014

In this research, split-type complex yarn of 20:80, 40:60, 50:50 nylon6/polyester composition ratio was used in order to impose unique sense on split-type complex woven. After treating both split-type complex yarn of each ratio and its produced woven in alkali solution, we got the following results by checking physical properties based on alkali proportion and treatment time. Under the condition of NaOH 20% in this experiment, it took approximately double time 20% loss of weight. The loss of weight became high when polyester proportion of N/P(nylon6/polyester) composition ratio was low, in the same fineness yarn. Even though polyester proportion was low, the loss of weight was low when the fineness was high. N/P division was well processed at about 25% loss of weight under the condition of NaOH 20%, treatment temperature $50^{\circ}C$, and treatment time 60 minutes. The research provides that the loss of weight should be processed around treatment time 24 hours in the case of NaOH concentration 15%, and treatment time 15 hours in the case of NaOH concentration 18%, respectively, in order to achieve N/P woven division ratio of about 70%-80% in industrial fields.

• 한국진공학회지
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• 제13권1호
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• pp.14-21
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• 2004

오늘날 전력소자의 작동에 고주파를 사용하기 때문에 에너지 손실을 줄이기 위해 전력소자의 스위칭 속도를 증가시키는 것은 필수적이다. 본 연구에서는 $p^+- n^-$ 접합 다이오드의 스위칭 속도를 증가시킬 목적으로 minority carrier의 수명을 감소시킬 수 있는 전자조사를 실시하였다. 다이오드의 전기적 성질에 대한 전자조사의 효과를 나타냈다. 스위칭 속도는 효과적으로 증가하였다. 또한 증가될 것으로 예상되는 접합 누설 전류와 전자조사 후 정전압강하는 최적 조건의 에너지와 dose량으로 조사된 $p^+- n^-$접합 다이오드에서는 무시할 수 있는 정도로 나타났다. DLTS와 C-V 분석은 실리콘 기판에서 전자조사로 감소된 결함은 0.284eV와 0.483eV의 에너지 준위를 갖는 donor-like 결함인 것을 보여준다. 본 연구에서의 실험 결과를 고려해 보면, 전자조사는 $p^+- n^-$ 접합 다이오드 전력 소자의 스위칭 속도를 증가시켜 에너지 손실을 감소시킬 수 있는 가장 유용한 기술이라고 결론지을 수 있다.

• The Korean Journal of Ecology
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• 제26권6호
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• pp.335-340
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• 2003

Patterns of mass loss and nutrient release from decomposing oak (Quercus mongolica) and mixed litters (Q. mongolica, Betula schmidtii, Acer pseudo-sieboldianum, Kalopanx pictus and Tilia amurensis) in a natural hardwood forest in Gyebangsan (Mt.) were examined using litterbags placed on the forest floor for 869 days. Mass loss rates from decomposing litter were consistently higher in mixed litter (59%) than in oak litter types (52%) during the study period. Nutrient concentrations such as nitrogen (N), phosphorus (P), potassium (K), and magnesium (Mg) from decomposing litter were also higher in mixed litter than in oak litter types. Nutrient concentrations (N, P, Ca, and Mg) increased compared with initial concentration of litter, while K concentrations dropped rapidly at the first 5 months and then stabilized. The results suggest that mas loss and nutrient release obtained from decomposing litter of single species in mixed hardwood forest ecosystem should be applied with caution because of the potential differences of mass loss and nutrient release between single litter and mixed litter types.

• Journal of Korean Dental Science
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• 제3권1호
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• pp.5-10
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• 2010

This study sought to compare the amounts of posterior anchorage loss during the en masse retraction of the upper anterior teeth between orthodontic mini-implant (OMI) and conventional anchorage reinforcement (CAR) such as headgear and/or transpalatal arch. The subjects were 52 adult female patients treated with sliding mechanics (MBT brackets, .022" slot, .019X.025" stainless steel wire, 3M-Unitek, Monrovia, CA, USA). They were allocated into Group 1 (N=24, Class I malocclusion (CI), upper and lower first premolar (UP1LP1) extraction, and CAR), Group 2 (N=15, Cl, UP1LP1 extraction and OMI), and Group 3 (N=13, Class II division 1 malocclusion, upper first and lower second premolar extraction, and OMI). Lateral cephalograms were taken before (T0) and after treatment (T1). A total of 11 anchorage variables were measured. Analysis of variance was used for statistical analysis. There was no significant difference in treatment duration and anchorage variables at T0 among the three groups. Groups 2 and 3 showed significantly larger retraction of the upper incisor edge (U1E-sag, 9.3mm:7.3mm, P<.05) and less posterior anchorage loss (U6M-sag, 0.7~0.9mm:2mm, P<.05; U6A-sag, 0.5mm:2mm, P<.01) than Group 1. The ratio of retraction amount of the upper incisor edge per 1 of anchorage loss in the upper molar made for the significant difference between Groups 1 and 2 (4.6mm:7.0mm, P<.05). Group 3 showed a relatively distal inclination of the upper molar (P<.05) and the intrusion of the upper incisor and first molar (U1E-ver, P<.05; U6F-ver, P<.05) compared to Groups 1 and 2. Although OMI could not shorten the treatment duration, it could provide better maximum posterior anchorage than CAR.

• Journal of Applied Biological Chemistry
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• 제43권4호
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• pp.258-263
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• 2000

The study was carried out to investigate the nutrient losses at a paddy field located at the southwest of central Korea from May 1, 1997 to April 30, 1998. The studying area was 10 ha. The amounts of nutrients loaded by runoff water were measured as follows. The total-N was 1,031 and $61kg\;10ha^{-1}$ during the irrigation and non-irrigation periods, respectively. The total amount of N from both periods was $1,092kg\;10ha^{-1}\;yr^{-1}$. The total-P was 23 and $2kg\;10ha^{-1}$ during the irrigation and non-irrigation periods, respectively. The total amount of P from both periods was $25kg\;10ha^{-1}\;yr^{-1}$. For percolationloss, the losses of total-N, ammonia-N, nitrate-N, and total-P were 167,30,122, and $3kg\;10ha^{-1}$, respectively. The respective loss ratios of N and P by runoff water were 55.2 and 11.9%, while the loss ratios of N and P by percolationwere 8.4 and 1.4%.