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A Study of Evaluating Streetscape Green Environments to Improve Urban Street Green Spaces - A Case Study of Jeonju City - (도시가로녹지의 개선을 위한 녹화환경평가 연구 -전주시를 대상으로-)

  • Jeong, Moon-Sun;Lim, Hyun-Jeong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.3
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    • pp.55-71
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    • 2019
  • The purpose of this study is to propose an evaluation method to assess green environments of streetscapes to improve urban street green spaces in Jeonju City. Through a rapid assessment of urban street green spaces, we suggest an objective basis for expanding street green space as well as for adopting sustainable maintenance and improvement measures. We choose 12 sections of streetscapes (roads and sidewalks) to investigate existing street conditions which have more than four lanes and function as major road axes. Six large roads and six medium roads of Jeonju City center area are investigated as pilot assessment study sites. Site inventory checklists consist of environmental characteristics of streetscape, street tree status, and planting condition evaluation. Environmental characteristics of streetscapes are composed of physical and neighborhood factors. For instance, items for physical factors are types and width of road/sidewalks, paving materials, tree protection materials, and green strip. And surrounding landuse is a neighborhood factor. Assessment items for street tree status are street plant names (tree/shrubs/ground cover), size, and planting intervals. Planting condition evaluation items are tree shape, damage, canopy density, and planting types with existence of adjacent green space. Evaluation results are classified into three levels such as A(maintain or repair), B(greening enhancement), and C(structural improvement). In case of grade A, streetscapes have enough sidewalk width for maintaining green strip and a multi-layered planting(in large road only) with fairly good growing conditions of street trees. For grade B and C, streetscapes have a moderate level of sidewalk width with a single street tree planting. In addition, street tree growing conditions are appeared poor so that green enhancement or maintenance measures are needed. For median, only grade B and C are found as its planting growing foundations are very limited in space. As a result, acquiring enough sidewalk space is essential to enhance ecological quality of urban street green. Especially, it is necessary to have green strip with reasonable widths for plant growing conditions in sidewalks. In addition, we need to consider native species with multi-layer plant compositions while designing street green.

A study on the Material and Characteristics of Glass Beads from Oc Eo Site, Vietnam (베트남 옥 에오(Oc Eo) 유적 출토 유리구슬의 재질 및 특성 연구)

  • Kim, Gyu Ho;Yun, Ji Hyeon;Kwon, Oh Young;Park, Jun Young;Nguyen, Thi Ha
    • Korean Journal of Heritage: History & Science
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    • v.49 no.2
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    • pp.158-171
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    • 2016
  • The observation and analysis results of 9 glass bead samples collected from Oc Eo site in Vietnam, an outport of the ancient port city Funan in East Asia, are as follows. The type of glass beads is round, the colors are reddish brown, greenish blue, green, black and purplish blue, and the chemical composition is soda glass group. This means that they are similar in type, color and chemical compositions to glass beads from the ancient Korean peninsula. There are limitations in data because the glass beads are not from excavation investigation but from earth surface investigation. But it is significant that similar making technique and chemical composition are being observed in both the glass beads from Oc Eo and those of Korea. According to "Nihon Shoki" Kinmeiki, Baekje king sent Funan's goods and 2 slaves to Japan in 543. It is clear that there were direct or indirect exchanges between Baekje and Funan. The possibility has grown that glass beads could be included among goods.

Rheological properties of arabinogalactan solutions isolated from the legumes (콩류 아라비노갈락탄 용액의 유변학적 성질)

  • Kim, Kyeong Yee;Kim, Choon Young
    • Korean Journal of Food Science and Technology
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    • v.51 no.4
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    • pp.330-335
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    • 2019
  • The aim of this study was to investigate the rheological properties of arabinogalactans (AGs) solution isolated from moth bean (MB), navy bean (NB), and soybean (SB) including monosaccharide compositions, intrinsic viscosity, steady shear and dynamic shear rheological properties. The major monosaccharides in MB, NB, and SB were arabinose (64.8, 51.4, and 42.6%) and galactose (13.4, 19.6, and 46.2%). The yield stresses for 5% (w/v) NB and 2.5% (w/v) SB solutions were assessed as 2.10 Pa and 1.98 Pa, respectively, but in case of MB solution, it was observed to be negligible. While 5% MB solution showed rheopectic property, 5% NB and SB solutions showed thixotropic properties. As a result of frequency sweep experiment, the G' values in 2.5% MB and NB were larger than the G" value showed but 2.5% SB exhibited G" value greater than G'. These results would be useful for future application as a food additive in the food industry.

Determination of the energy contents and nutrient digestibility of corn, waxy corn and steam-flaked corn fed to growing pigs

  • Ma, Dongli;Li, Juntao;Huang, Chengfei;Yang, Fengjuan;Wu, Yi;Liu, Ling;Jiang, Wei;Jia, Zhicheng;Zhang, Peijun;Liu, Xuezhen;Zhang, Shuai
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.10
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    • pp.1573-1579
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    • 2019
  • Objective: The research was conducted to determine the digestible (DE) and metabolizable energy (ME) contents as well as the apparent total tract digestibility (ATTD) of nutrients in corn, waxy corn and steam-flaked corn fed to growing pigs. Methods: Eighteen growing pigs with initial body weight of $15.42{\pm}1.41kg$ were randomly allotted to three diets including a corn diet, a waxy corn diet and a steam-flaked corn diet in a completely randomized design. Each treatment contained six replicates. The experiment lasted for 12 days, which comprised 7-d adaptation to diets followed by a 5-d total collection of feces and urine. The energy contents and the nutrient digestibility in three ingredients were calculated using direct method. Results: Compared to normal corn, both the amylose and dietary fiber contents in waxy corn were numerically lower, but the starch gelatinization degree was numerically greater. Moreover, the DE and ME contents as well as the ATTD of neutral detergent fiber and acid detergent fiber (ADF) in waxy corn were significantly greater (p<0.05) than those in normal corn when fed to growing pigs. Furthermore, the steam-flaked corn had greater (p<0.05) DE and ME contents, and ATTD of ether extract and ADF compared to normal corn. Conclusion: Both variety and processing procedure have influence on chemical compositions, energy contents and nutrient digestibility of corn. The waxy corn and steam-flaked corn had greater degree of starch gelatinization and DE and ME contents compared to normal corn when fed to growing pigs.

Ignition Characteristics of Petroleum-based and Bio Aviation Fuel According to the Change of Temperature and Pressure (온도와 압력의 변화에 따른 석유계 및 바이오항공유의 점화특성 분석)

  • Kang, Saetbyeol
    • Clean Technology
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    • v.25 no.3
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    • pp.238-244
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    • 2019
  • In this study, the ignition characteristics of petroleum-based aviation fuel (Jet A-1), bio aviation fuel (Bio-6308), and blended aviation fuel (50:50, v:v) were analyzed in accordance with change of temperature and pressure. The ignition delay time of each aviation fuel was measured by combustion research unit (CRU) and the compositions of the fuels were analyzed by GC/MS and GC/FID for qualitative and quantitative results. From the results, it was confirmed that the ignition delay times of all aviation fuels were shortened with increasing temperature and pressure. In particular, the effect of temperature was larger than the effect of pressure. Also, the ignition delay time of Jet A-1 was the longest at all measurement conditions, and it was judged that this result is because of the structurally stable characteristics of the benzyl radical generated during the oxidation reaction of the aromatic compound (about 22.48%) in Jet A-1. Also, it was confirmed that Jet A-1 had no section where the degree of shortening of ignition delay time was decreased by increasing temperature, which was because the benzyl radical inhibits the response that can affect the negative temperature coefficient (NTC). The ignition characteristics of blended aviation fuel (50:50, v:v) showed a similar tendency to those of Jet A-1, rather than to those of Bio-6308, so that the blended aviation fuel (50:50, v:v) can be applied to the existing system without any change.

Application of Science for Interpreting Archaeological Materials(II) - Production and Flow of Lead Glass from Mireuksa Temple - (고고자료(考古資料)의 자연과학(自然科學) 응용(應用)(II) - 익산(益山) 미륵사지(彌勒寺址) 납유리(琉璃)의 제조(製造) 및 유통(流通) -)

  • Kang, Hyung-Tae;Kim, Seong-Bae;Huh, Woo-Young;Kim, Gyu-Ho
    • Korean Journal of Heritage: History & Science
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    • v.36
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    • pp.241-266
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    • 2003
  • Glass pieces excavated from Mireuksa Temple dated $7^{th}$ century A.D. were characterized by chemical composition, specific gravity and melting point. Lead isotope ratios of lead glasses were also compared with those of lead ore to attribute which lead ore was delivered for making lead glass. It was known that some lead glasses found in Japan were similar with those of Mireuksa Temple as comparing the data of chemical composition and lead isotope ratios. Characteristics of lead glass from Mireuksa Temple Thirty five glass pieces of Mireuksa Temple were analyzed for five oxides and found that all was lead glass system(PbO-$SiO_2$) with the range of 70~79% for PbO and 20~28% for $SiO_2$. The concentrations of oxides such as $Al_2O_3$, $Fe_2O_3$ and CuO were below 0.4%, 0.3% and 0.9%, respectively. Principal component analysis(PCA) as a statistical method was carried out to classify glasses with the similarities of chemical concentrations. The result of PCA has shown that three groups of glasses were created according to the excavation positions and two major oxides(PbO and $SiO_2$) greatly contributed to the dispersion of glasses on principal component 1(PC1) axis and trace element oxides($Al_2O_3$ and $Fe_2O_3$) for PC2 axis. Most of lead glasses were greenish by the efficacy of iron and copper oxides and some showed yellowish-green. The gravity of lead glasses was about 4.4~5.4 and estimated melting point was near $670^{\circ}C$. Lead isotope ratios of glasses were analyzed and found quite close to a lead ore from the Bupyeong mine in Gyeonggi-do. Comparison with lead glasses found in Japan Lead glasses of Mireuksa Temple were compared with those of Japan on the basis of chemical and physical data. Chemical compositions of Japanese lead glasses dated $7^{th}{\sim}8^{th}$ century A.D. were nearly similar with those of Mireuksa Temple but lead isotope ratios of those were separated into two groups. Three distribution maps of lead ores of Korea, Japan and China with lead isotope ratios were applied for lead glasses found in Japan. The result have shown that the locations of lead glasses from Fukuoka Prefecture coincided with the region of northen part of Korea and similar with those of Mireuksa Temple and lead glasses from Nara Prefecture dated $8^{th}$ century A.D. were located in the region of Japanese lead ore. This research has demonstrated that lead glasses of Mireuksa Temple conveyed to Miyajidake site, Fukuoka Prefecture around $7^{th}$ century A.D. and glass melting pots and glass beads excavated from Nara Prefecture confirmed the first use of Japanese lead ore for production of lead glasses from the end of $7^{th}$ century A.D.

Transitions in Bronze Technology Observed in Bronze Artifacts Excavated from the Shilla Wang-Gyong (신라왕경 출토 청동유물에서 확인되는 청동기 제작기술의 변천)

  • Jeong, Young-Dong;Park, Jang-Shik
    • Korean Journal of Heritage: History & Science
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    • v.37
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    • pp.267-284
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    • 2004
  • As an initial step to understand the transitions in Korean bronze technology the present study has examined metallurgical microstructures of 8 artifacts excavated from the Silla Wang-Gyong site in Kyongju. Important trends have been found in alloy compositions and also in manufacturing processes. In the design of alloys, the Sn content was apparently changing toward the peritectic point, 22 mass %, of the Cu-Sn phase diagram while the Pb addition was intentionally avoided. This trend in composition was found accompanied by the introduction, subsequent to casting, of such special thermo-mechanical treatments as quenching and forging in artifact manufacture. In addition, the Sn content in alloys containing a significant amount of As was relatively low and no evidence of forging was observed in them. The use of quenching and forging and the rejection of Pb and As from alloys are all necessary requirements if the brittle nature of high Sn alloys is to be overcome in bronze working. This paper will show that the Wang-Gyong era corresponds to that of innovations leading to the technical climax in Korean bronze tradition, which has been maintained up to the present.

Effects of Environmental Substrate Composition on the Growth and Yield of Hydroponically Grown Tomato (토마토 양액재배시 배지 환경조성이 생육 및 생산성에 미치는 영향)

  • Lee, Jaesu;Lee, Hyundong;Lee, Sanggyu;Kwak, Kangsu;Kim, Balgeum;Kim, Taehyun;Baek, Jeonghyun;Rho, Siyoung;Hong, Youngsin
    • Journal of Environmental Science International
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    • v.28 no.9
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    • pp.729-735
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    • 2019
  • The aim of this study was to determine the effects of different compositions of environmental substrates on hydroponic tomato cultivation. Three different substrates were used in coir chip:dust (v/v=50:50; CP1), coir chip:dust (v/v=80:20; CP2), and rock wool cube with CP2 (CPR). The amount of irrigation during the cultivation period was 190 mL/(plant time) in all substrates. The pH and EC were 5.8-6.2 and 2.6-2.9 dS/m, respectively. The drainage rate in CP1 was 31%, in CP2 was 36%, and in CPR was 29%. The growth of tomato plants in terms of height was higher in CP1 and CPR. The leaf area was greater in CP2. The fresh and dry weights were greater in CP2 and CPR treatments. The net photosynthesis in CP2 ($19.31{\mu}mol\;CO_2/m^2s$) and root activity in CP2 were higher among all three treatments. The soluble solid content of fruit was not significantly different among treatments. The yield per plant in CP2 and CPR treatments was 17% greater than the yield per plant in CP1. Therefore, the most suitable substrate for hydroponic tomato cultivation is the substrate mixed with coir chip:dust (v:v=80:20; CP2), i.e., CPR.

Effects of Exercise and Nutrition on Male Body Composition and Obesity (운동과 영양 조절이 남성 연령별 체조성 및 비만에 미치는 영향)

  • Huh, Man Kyu
    • Journal of Life Science
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    • v.29 no.1
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    • pp.45-51
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    • 2019
  • This study is to investigate the effects of the physical activity and intake of improved food levels on male body compositions. Forty men were assigned to a percentage of body fat (PBF) group (20 men with physical exercise and food) and CONTROL group (20 men with exercise, food intake is free) for this six-month study. An aerobic capacity test to measure maximum oxygen consumption ($VO_2$ max) was performed to precisely determine the exercise intensities during the experimental conditions. After exercise and food control, the body weight of 20s with exercise and food (A) and only exercise (B) decreased about 2.3 kg and 0.4 kg after 6 months, respectively. If the p-values were 0.697(between baseline and 3 months), 0.535(between 3 months and 6 months), and 0.617(between baseline and 6 months), respectively, then 20s men had evidence of that a significant main effect does not exist amongst the observations of the outcome or within-weights. Their skeletal muscle mass (SMM) of both groups increased slightly through exercise. Although the decrease in total body weight of 30s was correlated with the increase in SMM, there was not shown significant. While total body water decreased in 20s, 40s, and 50s except 30s men, all other values did not shown significant differences. The physical activity and intake of improved food levels were contributed with lost a lot of weight, decrease of SMM and body fat.

Determination and prediction of the digestible and metabolizable energy contents of corn germ meal in growing pigs

  • Shi, Meng;Liu, Zhaoyu;Wang, Hongliang;Shi, Chuanxin;Liu, Ling;Wang, Junjun;Li, Defa;Zhang, Shuai
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.3
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    • pp.405-412
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    • 2019
  • Objective: This experiment was conducted to determine the chemical composition, digestible energy (DE) and metabolizable energy (ME) contents of corn germ meals (CGM) and to develop equations to predict the corresponding energy contents based on the chemical characteristics of individual CGM. Methods: Sixty-six barrows (initial body weight = $51.3{\pm}4.6kg$) were allotted to 11 diets including a basal diet and 10 CGM test diets in a completely randomized design. In the test diets, CGM was included in replacement of 30% of the energy-providing ingredients in the basal diet, resulting in a final inclusion rate of 29.1%. Each diet was fed to 6 barrows housed in individual metabolism crates for a 7-d acclimation period followed by a 5-d total but separate collection of feces and urine. Results: Considerable variation was observed in acid-hydrolyzed ether extract, ether extract, ash, calcium (Ca) and total phosphorus contents among the CGM samples. On dry matter (DM) basis, the DE and ME contents of the CGM ranged from 10.22 to 15.83 MJ/kg and from 9.94 to 15.43 MJ/kg, respectively. The acid detergent fiber (ADF) contents were negatively correlated with the DE and ME contents of CGM samples. The best-fit prediction equations for the DE and ME values (MJ/kg DM) of the 10 CGM were: DE = 26.85-0.28 insoluble dietary fiber (%)-17.79 Ca (%); ME = 21.05-0.43 ADF (%)-11.40 Ca (%). Conclusion: The chemical compositions of CGM vary depending on sources, particularly in ether extract and Ca. The DE and ME values of CGM can be predicted based on their chemical composition in growing pigs.