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The Effects of Soil factors on the Growth in Populus euramericana Guinier (토양인자(土壤因子)가 이태리 포플러의 생장(生長)에 미치는 영향)

  • Son, Doo Sik;Hong, Sung Chun;Joo, Sung Hyun
    • Current Research on Agriculture and Life Sciences
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    • v.14
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    • pp.49-60
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    • 1996
  • In order to evaluate soil factors affecting the growth of Italian poplar, 23 areas planted with Italian poplar were surveyed. These 23 areas were classified into 3 categories, river-side, fallow-land and hill-side. The growth performance and soil factors for each area were investigated. The growth of Italian poplar at river-side was shown to be superior to that of fallow-land and fill-side. The rates of growth for fallow-land and hill-side are decreased by 8% and 21% compared to those of river-side, respectively. This suggests that plantation of Italian poplar at hill-side would not be profitable. Soil conditions of high productive area appeared liquid phase 20%, porosity 45%, water holding capacity 35 - 40%, soil hardness $1kg/cm^3$. pH 6 and rich in organic matter and total nitrogen. The results of factor analysis for soil factors affecting to Italian poplar growth that showed eigenvalue over 1 and communality value over 70% explained factor 1 : liquid phase, porosity and water holding capacity, factor 2 : pH and calcium, and factor 3 : soil hardness. This suggests that physical characteristics of soil is more important than chemical characteristics for Italian poplar growth. Multiregerssion analysis was conducted between diameter growth and soil hardness, liquid phase and calcium. The t-values for each independent variables showed significance at 1 - 10% level, but water holding capacity and pH are not significant. It is supposed that sites suitable to Italian poplar were alluvial plain of sandy loam or part of banking soil, well-ventilating soil, lower soil hardness, apposite soil moisture absorbing with about 100cm of ground water level, plentiful organic matters and total nitrogen and little acidity soil.

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Analysis of Chinese Consumer Preference of Country of Origin for Apples based on National Organic Certification (사과의 국가별 유기인증 결합에 대한 중국 소비자 선호분석)

  • Kwon, Jae-Hyun;Kim, Jeong-Nyeon;Hong, Na-Kyoung;Kim, Tae-Kyun
    • Current Research on Agriculture and Life Sciences
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    • v.32 no.4
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    • pp.225-230
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    • 2014
  • This study investigates the effect of organic certification of apples on consumer preference in China as a way to support the expanded export of Korean apples to China. A choice experiment was designed to analyze the apple consumption in China. A total of 298 Chinese consumers answered the survey, and multinomial logit models were used to analyze the results. Organic certification was identified as an important determinant of consumer preference for apples in China, affecting both the evaluation and choice of country of origin. The results also indicated that Korean organic certification significantly increased the probability of Chinese consumers choosing Korean apples. Thus, organic certification by the Korean government should be strengthened to promote apple exports to China, plus the results of this study may provide useful information to promote agricultural product exports and improve the organic certification system.

Chemical Modification of Silk by Ethylene Cyanohydrin (에틸렌 시아노히드린에 의한 실크의 화학적 개질)

  • Lee, Geun-Souk;Bae, Do-Gyu
    • Current Research on Agriculture and Life Sciences
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    • v.26
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    • pp.23-30
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    • 2008
  • In this paper, when the silk fabric was modified by ethylene cyanohydrine, the reaction mechanism between both was studied at various treatment conditions such as curing temperatures and times, ethylene cyanohydrin concentrations and $ZnCl_2$ concentrations. Through the FT-IR and DSC analyses of the treated silk fabrics, we found the results as follows : It was observed in FT-IR analysis of the treated silk fabrics that the -OH characteristic peak($3,450cm^{-1}$)position and shape were all changed when drying and curing treatment conditions were at $80^{\circ}C$ for 3 minute and $110^{\circ}C$ for 2.5 minute, and the concentration of the $ZnCl_2$ was 0.1%. It indicated that the -OH group of the silk participated in the reaction between the silk fabric and ethylene cyanohydrin. From the DSC analysis, it was found that the pyrolysis temperatures of the treated silk fabrics by ethylene cyanohydrin which was processed in the same condition, were all increased from $311^{\circ}C$ to ab. $320^{\circ}C$. From the FT-IR analyses of the silk fabrics treated by ethylene cyanohydrin at the various concentrations of $ZnCl_2$, it was found that the -OH characteristic peaks($3,450cm^{-1}$) were similar to the nontreated one except that of the fabric treated at the $ZnCl_2$ conconcentration of 0.8% when drying and curing treatment conditions were at $80^{\circ}C$ for 3minute and $110^{\circ}C$ for 2.5 minute, and the concentration of the ethylene cyanohydrin was 5%. In the case of the $ZnCl_2$ concentration of 0.8% solution, a lot of change were observed in peak. From the DSC analysis of the treated silk fabrics which was processed in the same condition, it was showed that the pyrolysis temperatures of treated silk fabric were all increased from $311^{\circ}C$ to ab. $320^{\circ}C$, which was no relation with the concentration of $ZnCl_2$.

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Environmental Geochemical Characteristics of the Acid Mine Drainage and Stream Sediments in the Abandoned Honam Coal Mine Area, Korea (호남탄전지역 폐탄광의 산성광산배수와 하상퇴적물의 환경지구화학적 특성)

  • Park, Young-Seog;Kim, Jong-Kyun;Kim, Jin;Jang, Woo-Seog;Lee, Ki-Hyung;Han, Min-Su
    • Economic and Environmental Geology
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    • v.35 no.3
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    • pp.241-255
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    • 2002
  • The purpose of this study is to investigate environmental geochemical characteristics for the acid mine drainage and stream sediments in the abandoned Honam coal mine area. For the chemical analysis, stream winter samples were collected at 54 sites and for the mineralogical and chemical analysis, stream sediments samples were collected at 34 sites. Physical and chemical characteristics of stream water were measured at the site and chemical compositions were analyzed by ICP-AES, ICP-MS and IC. Mineralogical characteristics of stream sediments samples were determined using XRD, SEM and EDS. In physical and chemical properties, stream water shows thats pH 2.85~8.12, Eh -62~215 mV, EC 0.205~146 ms/m, ER 0.234~255 {$\Omega}{\cdot}$m, DO 0.03~1068 mg/L and TDS 10.96~1420mg/L. In chemical compositions, we obtain that K 0.118~3.184 mg/L, Mg 2.1~114.48 mg/L, Ca 2.59~l25.02 mg/L, Al 0.01~44.72 mg/L, Fe 0.108~89.49 mg/L and Na 5.45~125.41 mg/L. Stream sediments are commonly composed of quartz, illite and goethite in the result of x-ray diffraction. After heat treatment at 98$0^{\circ}C$, the hematite peaks are distinctly shown. In consideration of heavy metals (include Fe) for steam sediments, Fe ranges 22575~34713 ppm, Zn 41.66~970.3 ppm, Cd 0.52~52.07 ppm, Cu 1.25~198.5 ppm and Pb 0.43~77.35 ppm.

Factors Related to Knowledge, Health Belief and Sick Role Behavior to the Coronary Artery Disease among Patients with Coronary Artery Disease (관상동맥질환자의 관상동맥질환에 대한 지식, 건강신념 및 환자역할행위에 관련된 요인)

  • Kang, Young-Ok;Cho, Young-Chae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.11
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    • pp.4985-4994
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    • 2011
  • The purpose of this study was to investigate the level of knowledge, health belief and sick role behavior, and the influencing factors on them among the patients with coronary artery disease. The study subjects were 168 patients diagnosed as having coronary artery disease at a university hospital during the period from July 1st, to August 31th, 2010. As a results, Based on the mean scores of knowledge about coronary artery disease according to the general characteristics, they were significantly higher in males than in females(p=0.033). The mean scores of health belief were significantly higher according to age decrease(p=0.043). The mean scores of sick role behaviors were significantly higher in females than in males(p=0.006), with their increasing tendency in the age range from 40's to 60's and decreasing tendency in the age over 70's(p=0.015), the group with religion were significantly higher than the one without(p=0.050). In terms of the mean scores of knowledge and sick role behaviors about coronary artery disease according to the related characteristics, there was a significant difference with the time period elapsed after diagnosed as coronary artery disease, frequency of admissions, perception about the disease, information gathering through mass com. but in terms of those of health belief, there was a not significant difference in all the variables. The significantly influencing factors on degree of knowledge by multivariate regression analysis included degree of perception about a disease, scores of sick role behavior, presence of coronary artery diseases in a family or friends, and the time period elapsed after diagnosed as having coronary artery disease. Those on health belief included age and scores of sick role behavior, and those on sick role behaviors included score of knowledge, perception about a disease, age, BMI, and religion. The results showed a significant difference with their general characteristics or coronary artery disease-related factors.

Distribution characteristics of chemical oxygen demand and Escherichia coli based on pollutant sources at Gwangyang Bay of South Sea in Korea (남해 광양만에서 오염원에 따른 화학적 산소요구량과 대장균의 해역별 분포특성)

  • Baek, SeungHo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.5
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    • pp.3279-3285
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    • 2014
  • This study aimed to understand seasonal and geographical characteristic of chlorophyll-${\alpha}$ (chl-${\alpha}$), COD (chemical oxygen demand) and Escherichia coli at Gwangyang Bay during the period from February 2010 to November 2012. The bay is divided into three different zones based on the pollutant levels and geographical characteristics. During the study periods, water temperature, salinity, Chl. ${\alpha}$, and chemical oxygen demand (COD) varied in the range of $4.68-28.63^{\circ}C$, 1.94-33.84 psu, 0.31-35.10 ${\mu}gL^{-1}$, and 0.70-13.35 $mgL^{-1}$, respectively. Total chl-a concentration were high at the zone I, which can be characterized as a semi-enclosed eutrophic area, and it were low at the zone III, which is influenced by low nutrients of surface warm water current from offshore of the bay. The high concentration of COD was observed at inner bay during the four seasons and the water quality level was kept to be bad condition during spring season at the zone II, which is influenced by Seomjin River water. The highest colony form of E. coli was recorded to be 3550 $cfuL^{-1}$ during summer at station 1 (zone I), whereas it was relatively kept low level during all seasons at the zone III. As a result, the E. coli was correlated with water temperature (r=0.31 p<0.05) and salinity (r=-0.55 p<0.05), implying that those parameters have play an important crucial role in proliferation of E. coli. Consequently, our results indicated that the E. coli can be significantly promoted within pollutant sources including the high nutrients supplied by rive discharge during spring and summer rainy seasons in semi-enclosed area of Gwangyang Bay.

A Study on Applicability of Stabilizing Pile to Foundation Soil of Slope with Various Strength Parameters (사면하부지반의 강도정수에 따른 억지말뚝 적용성 연구)

  • Lee, Seung-Hyun;Jang, In-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.10
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    • pp.331-337
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    • 2016
  • Several foundation soil conditions below a homogeneous sand slope were assumed and slope stability analyses were conducted to determine the soil condition, in which a stabilizing pile can be used to increase the factor of safety against sliding. The assumed heights of the sand slope were 5m and 10m. For a 5m slope height, a stabilizing pile can be used in the foundation soil with a $15^{\circ}$ internal friction angle and a cohesion of 10kPa. For a 10m slope height, a stabilizing pile can be used in the foundation soil with a $20^{\circ}$ internal friction angle and a cohesion of 10kPa and a stabilizing pile can be used in the foundation soil with a $0^{\circ}$ internal friction angle and 40kPa, 45kPa and 50kPa of cohesion. According to the analysis results of stabilizing pile-reinforced foundation soil, the length of the stabilizing pile and magnitude of the maximum bending moment were strongly affected by the internal friction angle of the foundation soil. The lengths of stabilizing pile, for an internal friction angle of $0^{\circ}$ were 4.6, 8.0 times greater than those with an internal friction angle of $5^{\circ}$. The magnitude of the maximum bending moment of the stabilizing pile for an internal friction angle of $0^{\circ}$ was 24.6 times greater than that for an internal friction angle of $5^{\circ}$. Practically, a stabilizing pile cannot be used for foundation soil with an internal friction angle of $0^{\circ}$. Considering the results derived from this study, the effects of a stabilizing pile can be maximized for soft foundation soil that is embanked with a slow construction speed.

Posterior Lumbar Interbody Fusion Using Posterolateral Placement of A Single Cylindrical Threaded Cage and Two Regular Cages : A Biomechanical Study (단일 나사형 Cage를 이용한 후방 요추체간 융합술과 두개의 나사형 Cage를 이용한 PLIF의 생체 역학적 비교)

  • Park, Choon Keun;Hwang, Jang Hoe;Ji, Chul;Kwun, Sung Oh;Sung, Jae Hoon;Choi, Seung Jin;Lee, Sang Won;Kim, Moon Kyu;Park, Sung Chan;Cho, Kyeung Suok;Park, Chun Kun;Yuan, Hansen;Kang, Joon Ki
    • Journal of Korean Neurosurgical Society
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    • v.30 no.7
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    • pp.883-890
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    • 2001
  • Objectives : An in vitro biomechanical study of posterior lumbar interbody fusion(PLIF) with threaded cage using two different approaches was performed on eighteen functional spinal units of bovine lumbar spines. The purpose of this study was to compare the segmental stiffnesses among PLIF with one long posterolateral cage, PLIF with one long posterolateral cage and simultaneous facet joint fixation, and PLIF with two posterior cages. Methods : Eighteen bovine lumbar functional spinal units were divided into three groups. All specimens were tested intact and with cage insertion. Group 1(n=12) had a long threaded cage($15{\times}36mm$) inserted posterolaterally and oriented counter anterolaterally on the left side by posterior approach with left unilateral facetectomy. Group 2(n=6) had two regular length cages($15{\times}24mm$) inserted posteriorly with bilateral facetectomy. Six specimens from group 1 were then retested after unilateral facet joint screw fixation in neutral(group 3). Likewise, the other six specimens from group 1 were retested after fixation with a facet joint screw in an extended position(group 4). Nondestructive tests were performed in pure compression, flexion, extension, lateral bending, and torsion. Results : PLIF with a single cage, group 1, had a significantly higher stiffnesses than PLIF with two cages, group 2, in left and right torsion(p<0.05). Group 1 showed higher stiffness values than group 2 in pure compression, flexion, left and right bending but were not significantly different. Group 3 showed a significant increase in stiffness in comparison to group 1 for pure compression, extension, left bending and right torsion(p<0.05). For group 4, the stiffness significantly increased in comparison to group 1 for extension, flexion and right torsion(p<0.05). Although there was no significant difference between groups 3 and 4, group 4 had increased stiffness in extension, flexion, right bending and torsion. Conclusion : Posterior lumbar interbody fusion with a single long threaded cage inserted posterolaterally with unilateral facetectomy enables sufficient decompression while maintaining a majority of the posterior elements. In combination with a facet joint screw fixation, adequate postoperative stability can be achieved. We suggest that posterolateral insertion of a long threaded cage is biomechanically an ideal alternative to PLIF.

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A Single Index Approach for Time-Series Subsequence Matching that Supports Moving Average Transform of Arbitrary Order (단일 색인을 사용한 임의 계수의 이동평균 변환 지원 시계열 서브시퀀스 매칭)

  • Moon Yang-Sae;Kim Jinho
    • Journal of KIISE:Databases
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    • v.33 no.1
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    • pp.42-55
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    • 2006
  • We propose a single Index approach for subsequence matching that supports moving average transform of arbitrary order in time-series databases. Using the single index approach, we can reduce both storage space overhead and index maintenance overhead. Moving average transform is known to reduce the effect of noise and has been used in many areas such as econometrics since it is useful in finding overall trends. However, the previous research results have a problem of occurring index overhead both in storage space and in update maintenance since tile methods build several indexes to support arbitrary orders. In this paper, we first propose the concept of poly-order moving average transform, which uses a set of order values rather than one order value, by extending the original definition of moving average transform. That is, the poly-order transform makes a set of transformed windows from each original window since it transforms each window not for just one order value but for a set of order values. We then present theorems to formally prove the correctness of the poly-order transform based subsequence matching methods. Moreover, we propose two different subsequence matching methods supporting moving average transform of arbitrary order by applying the poly-order transform to the previous subsequence matching methods. Experimental results show that, for all the cases, the proposed methods improve performance significantly over the sequential scan. For real stock data, the proposed methods improve average performance by 22.4${\~}$33.8 times over the sequential scan. And, when comparing with the cases of building each index for all moving average orders, the proposed methods reduce the storage space required for indexes significantly by sacrificing only a little performance degradation(when we use 7 orders, the methods reduce the space by up to 1/7.0 while the performance degradation is only $9\%{\~}42\%$ on the average). In addition to the superiority in performance, index space, and index maintenance, the proposed methods have an advantage of being generalized to many sorts of other transforms including moving average transform. Therefore, we believe that our work can be widely and practically used in many sort of transform based subsequence matching methods.

Development of Evaluation Indicators for a Children's Dietary Life Safety Index in Korea (한국 어린이 식생활 안전지수의 평가 지표 개발)

  • Chung, Hae-Rang;Kwak, Tong-Kyung;Choi, Young-Sun;Kim, Hye-Young P.;Lee, Jung-Sug;Choi, Jung-Hwa;Yi, Na-Young;Kwon, Se-Hyug;Choi, Youn-Ju;Lee, Soon-Kyu;Kang, Myung-Hee
    • Journal of Nutrition and Health
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    • v.44 no.1
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    • pp.49-60
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    • 2011
  • This study was performed to develop a children's dietary life safety index required by the Special Act on Safety Management of Children's Dietary Life enacted in 2009. An analytical hierarchy process was used to obtain initial weights of dietary life safety evaluation indicators. The Delphi method was applied to develop the weights along with 98 food and nutrition professionals. Three representative policy indicators, nine strategy indicators, 11 main evaluation indicators, and 20 detailed evaluation indicators were selected for the children's dietary life safety assessment. Three policy indicators and nine strategy indicators were the following: children's food safety indicator (support level of children' safety, safety management level of children's favorite foods, and safety management level of institutional food service), children's nutrition safety indicator (management level of missing meals and obesity, nutrition management level of children's favorite foods, and nutrition management level of institutional food service), and children's perception and practice level indicator ("Dietary Life Law" perception level, perception, and practice level for dietary life safety management, perception, and practice level for nutrition management). Weights of 40%, 40%, and 20% were given for the three representative policy indicators. The relative importance of nine strategic indicators, which were determined by the Delphi method is as follows: For children’s food safety, support level of children's safety, safety management level of children's favorite foods, and safety management level of institutional food service were given weights of 12%, 9%, and 19%, respectively. For children's nutrition safety, the missing meals and obesity management level, nutrition management level of children's favorite foods, and the nutrition management level of institutional food service were given weights of 13%, 11%, and 16%, respectively. The "Dietary Life Law" perception level, perception and practice level of dietary life safety management, and perception and practice level of nutrition management were given weights of 4%, 7%, and 9%, respectively.