• Journal of Forest and Environmental Science
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• 제26권1호
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• pp.17-23
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• 2010

The present study was conducted to quantify wood and leaf litter decomposition and nutrient release of a dominant tree species, Tectona grandis Linn. F. in a tropical dry deciduous forest of Rajasthan, Western India. The mean relative decomposition rate was maximum in the wet summer and minimum during dry summer. Rainfall and its associated variables exhibited greater control over litter decomposition than temperature. The concentrations of N and P increased in decomposing litter with increasing retrieval days. Mass loss was negatively correlated with N and P concentrations. The monthly weight loss was significantly correlated (P < 0.05) with soil moisture and rainfall in both wood and leaf litter. Tectona grandis was found to be most suitable tree species for plantation programmes in dry tropical regions as it has high litter deposition and decomposition rates and thus it has advantages in degraded soil restoration and sustainable land management.

• 대한음성학회지:말소리
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• 제35_36호
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• pp.1-12
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• 1998

This study aims to investigate the prosodic characteristics of Korean discourse sentences, especially focusing the initial and final part of a sentence. 50 disourse sentences were read in two different styles; one, sentence by sentence, the other, continuous of all 50's. First, we tried to get two kinds of ratios from the acoustic results: first, ratio of the final syllable to the initial syllable in first word in a sentence; second, ratio of the final syllable to the initial syllable in last word in a sentence. We, then, calculated statistical values of the ratios including mean, standard deviation, minimum, maximum, and p-values in t-test. With respect to duration, there were little difference between two different styles. If any, we could see tiny unharmonious durational aspect in the initial of continuous reading. More concisely, there could be observed some deviation from standard. In case of F0, there was prominent statistical difference between ratios of last words in two styles. This difference might play a role as a prosodic feature. Energy seems to show similar pattern with that of F0. The results showed that final syllable in last word was pronounced with about 85 % of initial syllable in the same context and the last words in continuous speech were strongly articulated compared with those of sentence by sentence reading.

• Journal of the Korean Wood Science and Technology
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• 제30권4호
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• pp.23-26
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• 2002

현재 폐목재의 발생량은 국내의 연간 목재사용량의 40% 정도의 수준으로 국내의 목재자급율을 고려해볼 때, 목재패널산업에서의 이런 폐목재의 재활용은 많이 장려되어야 한다. 본 연구는 폐목재로부터 얻어진 파티클과 실험실에서 합성한 요소수지를 폐목재파티클의 전건무게에 대해 6% 첨가하여 열압온도 162℃와 열압시간 5분에서 파티클보드를 제조하고 ASTM D 1037 방법에 의해 파티클보드의 성능을 평가하였다. 파티클보드의 성능을 평가한 결과는 KS F 3104 파티클보드 8.0형의 최소요구를 만족시키는 것이다. 이런 파티클보드의 성능평가 결과는 폐목재가 파티클보드의 원료로 적합하다는 것을 보여준다.

• 한국식품영양학회지
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• 제31권5호
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• pp.737-750
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• 2018

Effects of acid soaking (AS) and thermal sterilization (TS) on the shape and quality characteristics of Tteokbokki rice cake (TRC) were investigated. The F-value of a sequential process (SP) of the combination of AS and TS was quantitatively determined with a reference microorganism of Bacillus cereus. F-values were evaluated according to the minimum and the maximum D-value of B. cereus and the reduction exponent (m=12). The heat penetration curves at cold point (CP) of TRC (400 g) were used to estimate the TS time at 121, 100, and $95^{\circ}C$. F-values of the SP were revised according to the adjusted m values after AS at different pH. The non-uniformity parameters (NUP) of TRC had no significant changes during AS but it dramatically increased after applying TS at a low pH by AS. The result of solubilized starch contents (SSC) demonstrated that the shape changes during SP are related to SSC. The texture characteristics and the whiteness were significantly influenced by a low pH condition (3.5) (p<0.05). Sensory analysis showed that a lower pH and a longer thermal processing time influenced negatively on the acceptability. This study showed that pH 4.0 and $95^{\circ}C$ was an optimum condition for the SP.

• Archives of Pharmacal Research
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• 제27권5호
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• pp.502-506
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• 2004

Two series of 2-(5-nitro-2-furyl)- and 2-(1-methyl-5-nitro-1H-imidazol-2-yl)-5-propyl, allyl and propargyl)thio-1,3,4-thiadiazoles (6a-f) and 2-(5-nitro-2-furyl)- and 2-(1-methyl-5-nitro-1 H-imidazol-2-yl)-5-(nitrobenzyl)thio-1,3,4-thiadiazole derivatives (8a-f) have been synthesized and evaluated against Mycobacterium tuberculosis, as part of the TAACF TB screening program under direction of the US National Institute of Health, the NIAID division. Primary screening was conducted at a single concentration, 6.25 $\mu\textrm{g}$mL$^{-1}$ , against M. tuberculosis H$_{37}$ Rv in BACTEC 12B medium, using the Microplate Alamar Blue Assay (MABA). The minimum inhibitory concentration (MIC) was determined for the compounds that demonstrated $\geq$90% growth inhibition in the primary screening. A varying degree of antituberculosis activity (from 0-97% of growth inhibition) was observed with the alkylthio series (6a-f), and the nitroimidazole derivative with a propylthio group (6b) and the nitrofuran derivative with a propargylthio group (6e), were the most active compounds (MIC=3.13 and 1.56 /$\mu\textrm{g}$mL$^{-1}$ , respectively). Among the nitrobenzylthio derivatives (8a-f), all the ortho, meta and para nitrobenzyl isomers in the nitrofuran series exhibited good antituberculosis activity (MIC=3.13 $\mu\textrm{g}$mL$^{-1}$ ), while the corresponding nitroimidazole analogues were completely inactive (Inhibition=0%).

• 한국지하수토양환경학회지:지하수토양환경
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• 제8권4호
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• pp.68-73
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• 2003

본 연구는 용도별 토양에 대한 중금속 및 불소 오염 조사를 하기 위하여 한강 남쪽에 위치한 11개 구청(양천구, 강서구, 구로구, 영등포구, 관악구, 동작구, 강남구, 강동구, 서초구)에서 비교적 오염 개연성이 구분될 것으로 판단되는 도로, 공장, 학교운동장, 적환장, 공원, 약수터 주변 등, 그동안 비교적 조사 자료가 부족하였던 토양을 대상으로, 6개의 용도별 시료를 채취하여 pH, Cd, Cu, Pb, Hg, F 항목을 분석하였다. 조사 결과 용도별 토양의 pH는 4.7∼9.5의 범위로 나타났으며, 중금속 및 불소 평균 농도는 Cd 0.391 mg/kg(0.011∼1.081 mg/kg), Cu 12.35 mg/kg(0.061∼73.62 mg/kg), Pb 13.04 mg/kg(N.D.∼61.85 mg/kg), Hg 0.0866mg/kg(N.D.∼l.3530mg/kg), F 206 mg/kg(47.1∼561 mg/kg)이었다. 용도별 토양에 대한 최대, 최저 농도는 Cd이 잡종지 0.632 mg/kg,학교용지 0.079 mg/kg, Cu는 도로용지 21.35 mg/kg, 학교용지 2.159mg/kg, Pb은 도로용지 24.70mg/kg, 학교용지 1.030mg/kg, Hg은 잡종지 0.1780 mg/kg, 학교용지 0.0087 mg/kg, F의 경우 임야 282 mg/kg, 학교용지 164 mg/kg로 나타나서 전체적으로 Cd, Cu, Hg은 대부분 적환장으로 이용되고 있는 잡종지가, Pb은 도로용지에서 각각 높은 농도를 나타내었고, F는 임야 지역을 대상으로 한 토양에서 높은 농도를 보였다. 그러나 학교용지는 Cd, Cu Pb, Hg. F등에서 상대적으로 다른 용도별 토양보다 낮은 농도를 나타내었다. 한편 조사대상 지역의 토양은 우리나라 토양 환경 우려 기준에는 대체로 적합하였으며 SQPI는 17.0∼211.1로 조사 대상 토양의 86.4%가 100미만으로 대체로 1등급에 해당하는 양호한 토양질을 유지하고 있는 것으로 조사되었다.

• 한국세라믹학회지
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• 제39권3호
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• pp.222-225
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• 2002

Microwave dielectric properties of the layered and functionally graded materials (FGMs) of $Mg_{0.93}Ca_{0.07}TiO_3$ (MCT) and $(Ca_{0.3}Li_{0.14}Sm_{0.42})TiO_3$(CLST) were investigated as a function of the volume ratio of two components. Dielectric constant was decreased with an increase of the volume ratio of MCT which had a lower dielectric constant thant CLST. For the layered FGMs specimens, the difference of thermal expansion coefficients between two components induced thermal strain to dielectric layers, which was confirmed by the plot of ${\Delta}$k (X-ray diffraction peak width0 versus k (scattering vector) using the double-peak Lorentzian function, f(x). Quality factor of the specimens was affected by the thermal strain of dielectric layer, especially MCT layer. For the specimen with the volume ratio of MCT/CLST = 2, the qulaity factor of the specimen showed a minimum value due to the maximum thermal strain fo MCT layer.

• 대한조선학회지
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• 제4권1호
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• pp.49-54
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• 1967

The authors considered the effects of trim in the small coastal passenger boat upon resistance in this paper. Any change of trim no matter how small, necessarily produces some effect upon resistance. The relations between the resistance coefficients and trim were investigated through the towing test of the Model $MCI-P_1-65$, Korean Standardized Ship, GT 70 tons passenger boat in the gravitational tank. The Lines of the Model are given in Fig. 1. Principal dimensions and other characteristics vary with the trim in general. Those values varied with the trim for $MCI-P_1-65$ are tabulated in table 1. The resistance was measured at five conditions such as even keel, 0.0273L, (original designed trim) 0.0473L, 0.0663L, 0.0873L trim by the stern, fixing the displacement corresponding to the designed load water line. Model was made of wood in length of 3.5 feet coated with varnish, and without appendages. As the artificial turbulent stimulator, the sand strip method was used. The results of model towing tests, correcting to water temperature of $70^{\circ}F$, were expanded to full scale using the Schoenherr's friction formula and surface roughness allowance coefficient of 0.0004. The authors point out, the following results. 1) Optimum trim which gives the minimum resistance exists for every speed at constant displacement and each comes to the same value. For $MCI-P_1-65$ optimum trim is 0.0673L trim by the stern(Fig.4-The cross curves of the resistancecoefficients). 2) At constant displacement, when LCB(longitudinal position of center of buoyancy) varies with the trim, there exists optimum value of LCB which gives minimum resistance for every speed and each comes to the same value. For $MCI-P_1-65$ optimum position of LCB is 8%L aft from midship section (Fig.6).

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.2941-2951
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• 2023

The optimal minimum ECCD power is evaluated numerically for completely suppressing the 3/2 and 2/1 NTMs in the CFETR hybrid scenario. For two typical frequencies of ECCD sources launching from two upper launcher (UL) ports, f_ec = 210 GHz and 240 GHz with O1-mode, UL₁: (R_i, Z_i) = (8.47, 5.7) m and UL₂: (R_i, Z_i) = (8.2, 4.5) m, higher frequency of ECCD source launching from the UL₂ port is better than that low frequency counterpart from the UL₁ port. Using 240 GHz ECCD source launching from the UL₂ port, the minimum power required to fully suppress the two NTMs with precise ECCD alignment is 12.4 MW and 16.7 MW, respectively. When good alignment cannot be achieved, the results suggest that the misalignment should not exceed 0.02α, preferably 0.015α, corresponding to 4.4 cm and 3.3 cm. Considering engineering difficulty of high-frequency gyrotron sources, the optimal minimum ECCD power with the 210 GHz source launching from the UL₂ port is 17.9 MW and 20.6 MW for completely suppressing the 3/2 and 2/1 NTMs, respectively. In view of this, it is a good choice to select the 210 GHz ECCD source launching from the UL₂ port in the short and medium term.

• Asian-Australasian Journal of Animal Sciences
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• 제9권6호
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• pp.643-646
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• 1996

Experiments were conducted to determine potassium (K) requirement of mule ducklings. One-day-old ducklings with equal number of both sexes were fed diets containing graded levels of K for three weeks. In experiment 1, corn-soybean meal diet (CP 18.7%, ME 2,890 kcal/kg, K 0.80%) was used. The addition of K (0.00, 0.10, 0.20, 0.30, 0.40%) to the diet by potassium carbonate resulted in a decrease in weight gain and feed efficiency with the group fed on basal diet having the best performance. This means that the existing K in the basal diet is adequate for the growth of ducklings. In experiment 2, low K corn-isolated soy protein diet (K, 0.19%) was used. The supplementation of K (0.00, 0.16, 0.32, 0.48, 0.64%) resulted in an increase in weight gain and feed efficiency with the control group having the lowest performance. The minimum K requirement was found to be 0.49% for both maximum growth and best feed efficiency as determined by using bent-stick model.