• Journal of Ecology and Environment
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• 제32권4호
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• pp.237-247
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• 2009

This study was conducted to determine the carbon (C) contents in different mixed stands of P. dens if/ora and deciduous oak species in Gwangneung, central Korea. Five mixed stands with different ratios of P. densiflora and deciduous oak species were chosen based on the basal area of all trees ${\geq}\;5cm$ DBH: pure P. densiflora (P100D0), 70% P. densiflora + 30% deciduous oak species (P70D30), 44% P. densiflora + 56% deciduous oak species (P50D50), 37% P. densiflora + 63% deciduous oak species (P40D60), and 10% P. densiflora + 90% deciduous oak species (P10D90). Total C contents in the overstory (aboveground and belowground) vegetation were higher in the mixed stands (P70D30, P50D50, P40D60) than in the pure stands (P100D0, P10D90). Moreover, except for P40D60, C contents of forest floor (litter and coarse woody debris) were larger in the mixed stands (P70D30, P50D50) than in the pure stands. However, total soil C contents up to 30cm depth were highest in the pure deciduous oak stand than in the pure P. densiflora stand and mixed stands. Total ecosystem C contents (Mg/ha) were 163.3 for P100D0, 152.3 for P70D30, 188.8 for P50D50, 160.2 for P40D60, and 150.4 for P10D90, respectively. These differences in total ecosystem C contents among the different mixed stands for P. densiflora and deciduous oak species within the study stands were attributed by the differences in vegetation development and forest management practices. Among the five study stands, the total ecosystem C contents were maximized in the 1:1 mixed ratio of P. densiflora and deciduous oak species (P50D50).

• 한국인터넷방송통신학회논문지
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• 제15권2호
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• pp.23-29
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• 2015

$a^b{\equiv}c$(mod p)에서 a,c,p가 주어졌을 때 b를 구하는 이산대수 문제를 푸는 아기걸음-거인걸음 알고리즘은 p를 $m={\lceil}{\sqrt{p}}{\rceil}$개의 원소를 가진 m개의 블록으로 분할하고 거인 1명이 보폭 m으로 단방향으로만 $a^0$로 걸어가면서 찾는 방법이다. 본 논문은 기본적으로 p를 p/l, $a^l$ > p로 분할하고, 성인 1명이 보폭 l로 단방향으로 걸어가는 방법으로 변형시켰다. 또한, 성인 $2^k$명이 동시에 걸어가면서 b를 빠르게 찾는 방법으로 확장시켰다. 제안된 알고리즘을 $1{\leq}b{\leq}p-1$의 범위에서 $2^k$, (k=2)를 적용한 결과 기본적인 성인걸음수의 1/4로 감소시키는 효과를 얻었다. 결론적으로, 제안된 알고리즘은 아기걸음-거인걸음 알고리즘의 보폭 수를 획기적으로 단축시킬 수 있었다.

• 한국수정란이식학회지
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• 제24권3호
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• pp.189-197
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• 2009

Two-pore domain 칼륨($K_{2P}$) 통로는 흥분세포 및 비흥분세포의 안정막 전압을 일정하게 유지하는데 관여한다. 그러나 생식세포 및 생식기관에서 발현되는 $K_{2P}$ 통로의 분포영역 및 그 기능에 대해서는 연구자들에 의해 아직 정리되지 못하였다. 본 종설에서는 $K_{2P}$ 통로의 생식세포 및 생식기관에서 발현, 분포 및 생리학적 의의를 논하였다. $K_{2P}$ 통로는 인간 영양막세포, 자궁근층, 태반혈관계, 자궁평활근조직, 태반융모조직 및 임신자궁조직에서 발현되어 임신에 있어서 관련성을 제시되었다. 또한, $K_{2P}$ 통로는 마우스 전핵배, 원숭이 정자 및 한우의 난소, 정소, 난자, 정자 및 수정란에서 발현 변화를 보였다. 특히, $K_{2P}$ 통로는 체외배양 시 변화되는 온도, 산소분압과 같은 배양조건에 의해 조절되는 특징을 보임으로써 수정 및 배 발달에 영향을 줄 수 있는 인자로 제시되었다. 그리고 $K_{2P}$ 통로는 과산화수소에 의해 유도된 마우스 전핵배의 세포 사멸에 있어서 칼륨 이온의 유출에 관여함이 확인되었다. $K_{2P}$ 통로의 생식세포 및 생식기관 내 발현 형태와 생리학적 특징은 생식생리학에 있어서 이온 통로 관련 기능들을 이해하는데 도움이 될 것이다.

• 대한수학회지
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• 제56권4호
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• pp.985-1000
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• 2019

Let k be an integer with $k{\geq}3$. Define $h(k)=[{\frac{k+1}{2}}]$, ${\sigma}(k)={\min}\(2^{h(k)-1},\;{\frac{1}{2}}h(k)(h(k)+1)\)$. Suppose that ${\lambda}_1,{\ldots},{\lambda}_5$ are non-zero real numbers, not all of the same sign, satisfying that ${\frac{{\lambda}_1}{{\lambda}_2}}$ is irrational. Then for any given real number ${\eta}$ and ${\varepsilon}>0$, the inequality $${\mid}{\lambda}_1p^2_1+{\lambda}_2p^2_2+{\lambda}_3p^2_3+{\lambda}_4p^2_4+{\lambda}_5p^k_5+{\eta}{\mid}<({\max_{1{\leq}j{\leq}5}}p_j)^{-{\frac{3}{20{\sigma}(k)}}+{\varepsilon}}$$ has infinitely many solutions in prime variables $p_1,{\ldots},p_5$. This gives an improvement of the recent results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.317-319
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• 1997

We have studied the properties of $GaAs_{1-x}P_x$ epitaxial films on the GaP using VPE method by CVD. The surface carrier concentration and PL power increased with increasing the epitaxial temperature while PL wave length decreased. The Power out of the LED with $GaAs_{1-x}P_x$/GaP structure decreased with increasing the epitaxial temperature while the forward voltage of the LED increased. Specially, The LED of $GaAs_{1-x}P_x$/GaP structure represents good electrical and optical properties when the $GaAs_{1-x}P_x$ layer was epitaxially grown at $810^{\circ}C$.

• Journal of Animal Science and Technology
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• 제58권6호
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• pp.19.1-19.7
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• 2016

Background: Cowpea (Vigna unguiculata [L.]) is a legume cultivated throughout most tropical countries and is valued as food and feed for human and livestock respectively. The search for an improved cowpea variety has been on-going with the aim of improving traits such as grain yield, drought and pest resistance. But no information exist on the feeding value of these improved varieties. Phosphate (P) fertilizer application is recommended to augment grain yield in grain legumes but data on the effect of P fertilizer on haulm quality is limited. Results: Two separate experiments were conducted to determine the effect of P fertilizer dose on the nutritive value of haulms from different cowpea varieties (V). In experiment 1, effect of three P doses (30, 60 and 90 kg $P_2O_5/ha$) on in vitro gas production (IVGP) characteristics, concentrations of digestible organic matter (DOM), crude protein (CP), acid detergent fiber (ADF) and neutral detergent fiber (NDF) of haulms from five cowpea varieties (Zaayura-SARC 4-75, Songotra-IT97K-499-35, Hewale-IT93K-192-4, IT99K 573-1-1 and Asomdwe-IT94K-410-2) were investigated using the $3(P){\times}5(V)$ factorial treatment arrangements in a completely randomized design. In experiment 2, the effects of two P doses (30 and 90 kg $P_2O_5/ha$) and two varieties (Zaayura-SARC 4-75 and Hewale-IT93K-192-4) on the voluntary feed intake, live weight, haematology and carcass characteristics of Djallonke lambs were also assessed using a $2(P){\times}2(V)$ factorial treatment arrangement. The $V{\times}P$ interaction significantly affected CP, NDF and ADF with CP concentration increasing with increase in P doses in Zaayura-SARC 4-75 and Asomdwe-IT94K-410-2. Whilst an increase (P < 0.05) in NDF was observed in Songotra-IT97K-499-35and Asomdwe-IT94K-410-2 as P doses increased, the other V only increased from P dose 30 to 60 kg/ha and declined at P dose 90 kg/ha. The ADF decreased (P < 0.05) with increase in P dose for all V with the exception of Songotra-IT97K-499-35. There was a significant V effect on DOM with the highest reported in Zaayura-SARC 4-75 (43.44 %). Daily DM intake, carcass length and blood urea nitrogen of the lambs were significantly affected by the V x P interaction. There was a significant V effect on globulin and P effect on live weight at slaughter, dressed weight, chuck, leg, loin, rib and flank and liver and lungs. Conclusion: It can be concluded that nutrient concentrations of cowpea haulms were positively influenced by different P dose and varieties with favorable effects on growth, haematology and carcass composition of lambs. Varieties Zaayura-SARC 4-75 and Hewale-IT93K-192-4 at P dose at 90 kg/ha are recommended to enhance growth performance and carcass yield of Djallonke lambs.

• The Plant Pathology Journal
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• 제16권1호
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• pp.29-35
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• 2000

The internal transcribed spacer regions (ITS I, 5.8S and ITS II) of the ribosomal DNAs were amplified from Korean isolates of Phytophthora spp. and sequenced to characterize them. Sequences from 33 isolates previously identified as P. boehmeriae, P. cactprum, P. cambivora, P. capsici, P. cinnamomi, P. erythroseptica, P. infestans, P. megasperma, P. melonis, P. nicotianae, P. palmivora and P. sojae were compared with published sequences, and a phylogenetic tree was produced. All isolates belonging to 10 species, P. cactorum, P. cambivora, P. capsici, P. cinnamomi P. citricola, P. infestans, P. nicotianae, P. palmivora and P. sojae were clearly clustered into published isolates of each species above 97% bootstrap value. Cucurbits isolates of Phytophthora previously identified as either P. melonis or P. drechsleri showed distinct evolutionary lineages from the P. megasperma was closely related to isolates of P. cryptogea-P. drechsleri showed distinct evolutionary lineages from the P. cryptogea-P. drechsleri complex group, indicating that P. melonis is a valid species. A Korean isolate of P. megasperma was closely related to isolates of P. erythroseptica showed distant genetic relationship with published isolates of P. erythroseptica (CBS 956.87). It is probable that the two Korean isolates could be genetically different from foreign isolates or misidentified. A grouping of species according to ITS sequence divergence matched, to some degree, the broad classification based on type of papilla. However, a separation of semi-papillate species and papillate species was not wvident in this study.

• 한국식품과학회지
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• 제7권2호
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• pp.82-84
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• 1975

스물두개 품종(品種)의 보리쌀중 단백질함량(蛋白質含量)은 Mg와 P 함량(含量)과 1%에서, K 함량(含量)은 5% 수준(水準)에서 유의성(有意性)이 있으나 Ca와는 유의성(有意性)이 없었다. 색소결합능(色素結合能)(dye binding capacity)과는 Mg 와 P 함량(含量)과만 1%에서 유의상관(有意相關)이 있었다. Mg 및 P 는 단백질함량(蛋白質含量) 식별지표(飾別指標)로 사용(使用)될 가능성(可能性)을 보였다. 이들 4개무기성분함량(個無機成分含量)과 탄수화물(炭水化物)과는 모두 유의성(有意性)없는 부상관(負相關)을 보였다. P,K,Mg 상호간(相互間)에는 1% 수준(水準)에서 유의상관(有意相關)을 보였다. 보리쌀 중 $K_2O$,$P_2O_5$, CaO 및 MgO 의 평균(平均) 함량(含量)은 각기 0. 30, 0. 29, 및 0. 08, 0. 043%였다.

• 환경위생공학
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• 제5권1호
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• pp.28-33
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• 1990

춘천의 잣나무림과 관악산의 소나무림에 있어서 낙엽의 무기화를 연구하였다. N, P, K, Ca 및 Na의 무기화 상수를 보면 잣나무림에서는 각각 0.064, 0.068, 0.040, 0.047, 0.417, 0.058이었으며, 소나무림에서는 0.049, 0.049, 0.346, 0.058이었다. 무기물이 무기화되는 순서는 잣나무림에서는 Ca>P>N>Na>K였으며 소나무림에서는 Ca>Na>N=P>K로 나타났다. 일반적으로 양이온의 무기화는 음이온의 무기화보다 빨랐다.

• 대한화학회지
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• 제25권1호
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• pp.7-12
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• 1981

$p-CH_3, p-H, p-Cl 및 p-NO_2 기로 치환된 염화벤젠술포닐의 가용매분해반응을 MeOH-MeCN혼합용매계에서 연구하였다. 반응속도는 p-NO_2 > p-CH_3 > p-H > p-Cl의 순위로서 비직선 Hammett관계를 나타내어 S_N1-S_N2경계반응메카니즘으로 반응함을 알았다. 반응성은 모든 경우 약 90∼95% 메탄올용액에서 최대였으나, fi = \frac{k1}{ki}로 정의되는 각 기질의 메탄올 단위체 선택성(monomer selectivity)은 80% 메탄올 용액에서 최대이며, 그 크기 순위는 p-NO_2 > p-Cl > p-H > p-CH_3$로서 전이상태 구조가 tight할 수록 fi값이 크며 메탄올 단위체를 예민하게 선별 감지함을 알 수 있었다