• Journal of Forest and Environmental Science
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• 제32권2호
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• pp.212-218
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• 2016

The research was conducted windward of an irrigated Acacia amplicips Maslin windbreak established to protect As Salam Cement Plant from winds and moving sands. Two belts with approximate optical porosities of 50% and 20% were studied in River Nile State, Sudan. The research aimed at assessing the efficiency of the two belts in wind speed reduction and sand deposition. Research methods included: (i) estimation of optical porosity, (ii) measurements of windward wind speeds at a control and at distances of 0.5 h (h stands for windbreak height), 1 h and 2 h at two vertical levels of 0.25 h and 0.5 h, (iii) estimation of relative wind speeds at the three positions (distance and height) at windward and (iv) estimation of wind erosive forces and prediction of zones of sand deposition. Results show that while the two belts reduced windward wind speeds at the two levels for the three distances, belt II was more effective. Nearest sand deposition occurred at 2 h and 1h windward of belt II and belt I, respectively, at level 0.25 h. At level 0.5 h, sand was deposited only at 2 h windward of belt II and no sand deposition occurred windward of belt I. The study concludes that less porous windbreaks are more effective in reducing wind speed and in depositing sand in windward direction at a distance of not less than twice the belt height.

• The Plant Pathology Journal
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• 제39권3호
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• pp.265-274
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• 2023

Citrus black rot is a serious disease of citrus plants caused by Alternaria citri. The current study aimed to synthesize zinc oxide nanoparticles (ZnO-NPs) by chemically or green method and investigate their antifungal activity against A. citri. The sizes of synthesized as measured by transmission electron microscope of ZnO-NPs were 88 and 65 nm for chemical and green methods, respectively. The studied prepared ZnO-NPs were applied, in vitro and in situ, at different concentrations (500, 1,000, and 2,000 ㎍/ml) in post-harvest treatment on navel orange fruits to verify the possible control effect against A. citri. Results of in vitro assay demonstrated that, at concentration 2,000 ㎍/ml, the green ZnO-NPs was able to inhibit about 61% of the fungal growth followed by 52% of chemical ZnO-NPs. In addition, scanning electron microscopy of A. citri treated in vitro with green ZnO-NPs showed swelling and deformation of conidia. Results showed also that, using a chemically and green ZnO-NPs at 2,000 ㎍/ml in situ in post-harvest treatment of orange, artificially-infected with A. citri, has reduced the disease severity to 6.92% and 9.23%, respectively, compared to 23.84% of positive control (non-treated fruits) after 20 days of storage. The out findings of this study may contribute to the development of a natural, effective, and eco-friendly strategy for eradicating harmful phytopathogenic fungi.

• Asian-Australasian Journal of Animal Sciences
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• 제12권5호
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• pp.810-814
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• 1999

The influence of dietary vitamin E supplementation on meat color and ${\alpha}$-tocopherol concentrations in plasma, longissimus thoracis muscle and subcutaneous fat was investigated. Ten Japanese $Black{\times}Holstein$ crossbred steers were placed in three experimental groups receiving different supplements of vitamin E. Four steers (control) were fed no supplemental vitamin E. Two groups of three steers each, were supplemented with 500 mg dl-${\alpha}$-tocopherol acetate per animal daily for 175 days and 1,000 mg for 100 days, respectively, before slaughter. The ${\alpha}$-tocopherol concentration in plasma increased, as vitamin E were fed, and were related to the length of time and the amount of supplement. The ${\alpha}$-tocopherol concentrations in the muscle and the fat from the two supplemental groups did not differ significantly and were three or more times greater than those in the control group. Vitamin E supplementation did not affect the quantity of marbling of beef. Supplemental vitamin E stabilized the color of displayed beef around wavelengths of 500 nm and 640 nm. The two methods of vitamin E supplementation had similar effects on meat color. The effect of supplemental vitamin E on the color of beef with marbling was observed 2-3 days after slaughter and was followed for another two weeks.

• 한국신뢰성학회지:신뢰성응용연구
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• 제17권1호
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• pp.38-49
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• 2017

Purpose: The purpose of this study is to introduce the assessment model for industrial accidents prevention policy. Methods: 10 years of industrial accidents data are explored through EDA approach. Case control study is tried in order to assess the effectiveness of the measures taken by Korea Safety and Health Agency, Civilian, and 'Ministry of Employment and Labor'. Propensity score matching is used to match the characteristics of the two groups compared, and then case control study is again conducted. Next, logistic and Poisson regressions are used to assess the risk factors. Results: According to case control study involvement of 'Korea Safety and Health Agency' and 'Ministry of Employment and Labor' were not effective, but Civilian was. Propensity score matching leads to the same conclusion. Poisson regression reveals the impact of the risk factors on the industrial accidents. Industrial accidents occur more often as the number of employees grows. Mining, farming, fishing, 'transportation storage and telecommunication' and forestry have a higher level of industrial accidents but service industry has a lower level. It is odd that more involvement of Korea Safety and Health Agency, Civilian, and Ministry of Employment and Labor means more industrial accidents. Conclusion: 'Korea Safety and Health Agency', Civilian, and 'Ministry of Employment and Labor' seem to visit those industries with more industrial accidents.

• 한국환경복원기술학회지
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• 제3권2호
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• pp.66-74
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• 2000

This study was carried out to introduce current status and development strategy for an environmental restoration of stream side in Japan, and to consider a methodology which could be effectively applied for the environmental restoration of stream side in Korea. The strategy prospects of environmental restoration in Japan were summarized as follows: 1. We should establish a new paradigm of forest road, forest conservation and erosion control which can emphasize the restoration of the streamside ecosystem and reduce the effects of soil movement change in the areas. And we should maintain the biotic habitats to conserve native biotic community when we practice forest road, forest conservation and erosion control works. 2. In the point of view ecological conservation aspects, we should evaluate the effects of new forest conservation and erosion control methods which is emphasized on the restoration of the streamside ecosystem to apply desirable methodology to the environmental restoration of the streamside area. 3. In the past, the objective of forest conservation and erosion control was to fix a soil by construction of permanent structures. Whereas, the direction of future's forest conservation and erosion control needs to change new forest conservation and erosion control technology to prevent large scale soil movement but allow small scale soil movement to conserve sound ecosystem and biotic habitats. 4. The restoration of the streamside ecosystem should provide continuity of the streamside environment which allows desirable biological habitats, and environmentally sound facilities to harmonize the environment.

• 한국환경복원기술학회지
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• 제9권6호
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• pp.38-51
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• 2006

This study was carried out to improve rehabilitation effect by hydro-seeding methods on denuded slopes. Lespedeza cyrtobotrya, Indigofera pseudotinctoria, Arudinella hirta, Poa pratensis, and Lolium perenne were used in this study. The results of the germination and growth characteristics by seed coating, slope control and soil mulching treatments are summarized here. Seed coating of those plants had an effect on germination ratio, germination force, $LD_{50}$, and seedling growth of stem, leaf and root. The seed coating effect was highest for I. pseudotinctoria while the seedling growth was best for L. cyrtobotrya. Vermiculite+Talcum was the best coating material for germination and seedling growth of the plants. As the slopes were steeper, germination ratio was lower and seedling growth of stem and root decreased. Lots of seeds and soils were swept away when the slope was steep. Soil mulching was effective for germination, seedling growth of stem and root, and soil stabilization. It was more effective when the slope was steeper. Coir net was the most effective soil mulching material n this study.

• Structural Engineering and Mechanics
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• 제81권6호
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• pp.715-728
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• 2022

A new type of buckling-restrained braces (BRBs) with a longitudinally profiled steel plate working as the core (LPBRB) is proposed and experimentally investigated. Different from conventional BRBs with a constant thickness core, both stiffness and strength of the longitudinally profiled steel core along its longitudinal direction can change through itself variable thickness, thus the construction of LPBRB saves material and reduces the processing cost. Four full-scale component tests were conducted under quasi-static cyclic loading to evaluate the seismic performance of LPBRB. Three stiffening methods were used to improve the fatigue performance of LPBRBs, which were bolt-assembled T-shaped stiffening ribs, partly-welded stiffening ribs and stiffening segment without rib. The experimental results showed LPBRB specimens displayed stable hysteretic behavior and satisfactory seismic property. There was no instability or rupture until the axial ductility ratio achieved 11.0. Failure modes included the out-of-plane buckling of the stiffening part outside the restraining member and core plate fatigue fracture around the longitudinally profiled segment. The effect of the stiffening methods on the fatigue performance is discussed. The critical buckling load of longitudinally profiled segment is derived using Euler theory. The local bulging behavior of the outer steel tube is analyzed with an equivalent beam model. The design recommendations for LPBRB are presented finally.

• Asian-Australasian Journal of Animal Sciences
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• 제32권4호
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• pp.574-584
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• 2019

Objective: Research was conducted to test the effect of including fiber-rich feedstuffs in practical pig diets on nutrient digestibility, nitrogen balance and ammonia emissions from slurry. Methods: Three Vietnamese fiber sources were screened, namely cassava leaf meal (CL), cassava root residue (CR), and tofu by-product (TF). Accordingly, a control diet (Con) with 10% of dietary non-starch polysaccharides (NSP) and three test diets including one of the three fiber-rich feedstuffs to reach 15% of NSP were formulated. All formulated diets had the same level of crude protein (CP), in vitro ileal protein digestible and metabolisable energy, whereas the in vitro hindgut volatile fatty acid (VFA) production of the test diets was 12% to 20% higher than the control diet. Forty growing barrows with initial body weight at $28.6{\pm}1.93kg$ ($mean{\pm}standard$ deviation) were allocated to the four treatments. When pigs reached about 50 kg of body weight, four pigs from each treatment were used for a nitrogen balance trial and ammonia emission assessment, the remaining six pigs continued the second period of the feeding trial. Results: The TF treatment increased fecal VFA by 33% as compared with the control treatment (p = 0.07), suggesting stimulation of the hindgut fermentation. However, urinary N was not significantly reduced or shifted to fecal N, nor was slurry pH decreased. Accordingly, ammonia emissions were not mitigated. CR and CL treatments failed to enhance in vivo hindgut fermentation, as assessed by fecal VFA and purine bases. On the contrary, the reduction of CP digestibility in the CL treatment enhanced ammonia emissions from slurry. Conclusion: Dietary inclusion of cassava and tofu byproducts through an increase of dietary NSP from 10% to 15% might stimulate fecal VFA excretion but this does not guarantee a reduction in ammonia emissions from slurry, while its interaction with protein digestibility even might enhance enhanced ammonia emission.

• 한국산림과학회지
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• 제82권3호
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• pp.227-234
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• 1993

식(食) 약용수종(藥用樹種)으로 이용가치(利用價値)가 높은 초피나무 종자(種子)의 발아율(發芽率)을 높이는 발아촉진방법(發芽促進方法)을 찾기 위하여 종자(種子)를 Pon-Pon에 세척(洗滌)하고 4가지 방법(方法)으로 10월(月) 초순(初旬)에 처리(處理)한 후(後) 1991년(年) 4월(月) 포지(圃地)에 파종(播種)하여 발아생장(發芽生長)한 묘목(苗木)을 당년(當年) 10월(月) 중순(中旬)에 거취(据取), 발아율(發芽率)과 묘목생장량(苗木生長量)을 조사(調査)한 결과(結果)와 삽목증식법(揷木增殖法)을 개발(開發)하기 위하여 삽목시기(揷木時期) 및 발근촉진제(發根促進劑)의 종류별(種類別) 농도(濃度)에 따른 삽목묘(揷木苗)의 발근율(發根率)과 묘목생장(苗木生長)을 조사(調査)한 결과(結果)를 요약(要約하면 다음과 같다. 1. 종자발아촉진처리(種子發芽促進處理)에 따른 포지발아율(圃地發芽率)은 Pon-Pon 처리(處理) 후(後) 노천매장(露天埋藏)한 처리구(處理區)에서 74.3%로 가장 높았으며, 처리간(處理間)에 1% 수준(水準)에서 유의성(有意性)이 인정(認定)되었다. 2. 묘목(苗木)의 신장생장형(伸長生長型)은 춘기(春期)부터 추기(秋期)까지 연속신장형(連續伸長型)이었고 종자발아(種子發芽) 후(後) 48일(日)째인 7월(月) 1일(日)부터 7월(月) 31일(日) 사이에 당년(當年) 총(總) 생장량(生長量)의 40.3%가 생장(生長)하여 가장 왕성(旺盛)한 생장량(生長量)을 보였다. 3. 삽목묘(揷木苗)의 발근율(發根率)은 발근촉진제(發根促進劑) 종류간(種類間)에는 뚜렷한 차이(差異)를 보이지 않았으나 농도간(濃度間)에 1% 수준(水準)에서 유의적(有意的)인 차이(差異)를 보였다. 4. 삽목묘(揷木苗)의 일차근수(一次根數)와 T/R율(率)은 발근촉진제(發根促進劑) 처리구(處理區)가 무처리구(無處理區)보다 양호(良好)한 생장(生長)을 보여 주였다. 5. 삽목묘(揷木苗)의 T/R율(率)은 일차근수(一次根數)와 높은 부(負)의 상관(相關)(r=-0.7164)을 나타내었다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1251-1251
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• 2001

The routine analysis of milk chemical components is of major importance both for the management of animals in dairy farms and for quality control in dairy industries. NIRS technology is an analytical technique which greatly simplifies this routine. One of the most critical aspects in NIRS analysis of milk is sample preparation and analysis modes which should be fast and straightforward. An important difficulty when obtaining NIR spectra of milk is the high water content (80 to 90%) of this product, since water absorbs most of the infrared radiation, and, therefore, limits the accuracy of calibrating for other constituents. To avoid this problem, the DESIR system was set up. Other ways of radiation-sample interaction adapted for liquids or semi-liquids exist, which are practically instantaneous and with limited or null necessity of sample preparation: Transmission and Folded Transmission or Transflectance. The objective of the present work is to compare the precision and accuracy of milk calibration equations in two analysis modes: Reflectance (dry milk) and Folded Transmission (liquid milk). A FOSS-NIR Systems 6500 I spectrophotometer (400-2500 nm) provided with a spinning module was used. Two NIR spectroscopic methods for milk analysis were compared: a) folded transmission: liquid milk samples in a 0.1 pathlength sample cell (ref. IH-0345) and b) reflectance: dried milk samples in glass fibre filters placed in a standard ring cell. A set of 101 milk samples was used to develop the calibration equations, for the two NIR analysis modes, to predict casein, protein, fat and dry matter contents, and 48 milk samples to predict Somatic Cell Count (SCC). The calibrations obtained for protein, fat and dry matter have an excellent quantitative prediction power, since they present $r^2$ values higher than 0.9. The $r^2$ values are slightly lower for casein and SCC (0.88 and 0.89 respectively), but they still are sufficiently high. The accuracy of casein, protein and SCC equations is not affected by the analysis modes, since their ETVC values are very similar in reflectance and folded transmission (0.19% vs 0.21%; 0.16% vs 0.19% and 55.57% vs 53.11% respectively), Lower SECV values were obtained for the prediction of fat and dry matter with the folded transmission equations (0.14% and 0.25% respectively) compared to the results with the reflectance ones (0.43% and 0.34% respectively). In terms of accuracy and speed of analytical response, NIRS analysis of liquid milk is recommended (folded transmission), since the drying procedure takes 24 hours. However, both analysis modes offer satisfactory results.