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A Strategic Study of Pedestrian-Friendly Reconstruction in University Campus Core - Case Study of 'H' University in Gyeonggi-do Province - (대학 캠퍼스코어의 보행친화형 개조전략 연구 - 경기도 H대학교를 사례로 -)

  • Hong, Youn-Soon;Park, Chung-In
    • Journal of the Korean Institute of Landscape Architecture
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    • v.42 no.6
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    • pp.89-100
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    • 2014
  • The Campus Core is centered at the physical, functional and symbolic environment of a university, which is known as the top academic institution, hence it metaphorically represents not only the educational philosophy when institution first opened, but also the transformed values of the time. Today, universities are asked to actively communicate with the local community in terms of function and be remodeled as pedestrian-friendly campuses in terms of physical environment. For this reason, the study comprehends the concept of the campus core in accordance with a pedestrian-friendly environment and suggests a practical plan for campus cores of district national universities based on previous research examination. Since the purpose of the study is to suggest a change in the circulation system centered on vehicle use to transform into a pedestrian-friendly environment through a planned approach while introducing public mixed-use at the same time, the study supports the fact that it is possible to reorganize the strategy of a pedestrian-friendly circulation system and partially revise the land utilization to yield the expected outcomes. Thus, this study will provide valid suggestions for similar maintenance plans while looking back to the meaning and value of today's campus core.

Production of Activated Carbon from Waste Walnut Shell Using Phosphoric Acid and Its Adsorption Characteristics for Heavy Metal Ion (인산활성화제에 의한 폐호도껍질을 원료로 한 활성탄제조 및 이의 중금속 이온 흡착특성)

  • Lee Go-Eun;Ahn Ju-Hyun;Kim Dong-Su
    • Resources Recycling
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    • v.12 no.3
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    • pp.13-24
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    • 2003
  • The production characteristics of activated carbon from waste walnut shell have been investigated by taking activation temperature, activation time, amount of activating agent, and kind of activating agent as the major influential factors. The adsorption capacity of the activated carbon which was produced using phosphoric acid as the activating agent increased with activation temperature and showed its greatest value at about $550^{\circ}C$. Yield for activated carbon was observed to decrease continuously as the activation temperature was raised. The optimal activation time for the highest adsorption capacity was found to be about 2 hr, and as the activation time increased the yield for activated carbon was showed to decrease continuously. The increase in the amount of activating agent resulted in the increase of the yield for activated carbon, however, excessive amount of activating agent deteriorated its adsorption capacity reversely. The variations of the microstructure of activated carbon observed by SEM with several influential factors, correlated very well with its changes in the adsorbability with the same factors and the kind of activating agent was found to play an important role in the determination of the adsorption capacity of activated carbon. To investigate the adsorption characteristics of the produced activated carbon, the adsorption reactions of $Cu^{2+}$ ion were examined using the produced activated carbon as the adsorbent. In general, the kinetics of the adsorption of $Cu^{2+}$ ion was observed to follow a 2nd-order reaction and the rate constant for adsorption reaction increased as the initial concentration of adsorbate was diminished. The equilibrium adsorption of $Cu^{2+}$ was explained well with Freundlich model and its adsorption reaction was found to be endothermic. The activation energy for adsorption was calculated to be 13.07 kcal/mol, which implied that the adsorption reaction was very irreversible, and several thermodynamic parameters of adsorption reaction were estimated using van't. Hoff equation and thermodynamic relationships.

Moved of Applied Fertilizers through Volcanic Ash Soils in a Lysimeter Experiment (Lysimeter를 이용한 시비비료의 화산회토 토양중 이동에 관한 연구)

  • 강봉균;조남기
    • Journal of Soil and Groundwater Environment
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    • v.6 no.3
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    • pp.3-12
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    • 2001
  • This study conducted to Investigate the movement of fertilized nutrients in a volcanic ash soil in Jeju using by the pressure-vacuum soil water sampler. The percolated water to measure the ion concentration of leachates was taken from a lysimeter at depths of 20, 40, 60, 80, 100 and 120 cm in the soil in where a corn and potato were cultivated as a preceding and succeeding crop, respectively. Fertilizers of N-$P_2$O$_{5}$-$K_2$O were applied at the rate of 36-30-30 kg $10a^{-1}$ for the corn and 28-22-24 kg $10a^{-1}$ for the potato prior to planting of both crops. The highest concentrations of Cl , $NO_3$-N, $Ca^{+2}$ and $K^+$ in percolates were showed at 20cm and 40cm in soil depth at one month after fertilizing, and then gradually moved and reduced into below soil depths. At 5.5 months after fertilization, the concentrations in all soil depths were similar with the value of before fertilization. At depth of 120cm, the concentration of NO$_3$-N and the other cations in leachate was highest 1 to 1.5 months after fertilization. pH in percolated water was negatively correlated with NO$_3$-N concentration while the concentration of $NO_3$-N showed positive correlation between Cl, $Ca^{+2}$ and $Mg^{+2}$ concentrations. This result indicated that those cations can be leached out by accompanied with $NO_3$-N.

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Fabrication of Silicon Nitride Ceramics Using Semiconductor-Waste-Si Sludge (반도체 폐 Si 슬러지를 이용한 질화규소세라믹의 제조)

  • Lee, Byong-Taek;Yoo, Jung-Ho;Kim, Hai-Doo
    • Korean Journal of Materials Research
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    • v.9 no.12
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    • pp.1170-1175
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    • 1999
  • The microstructures and mechanical properties of $Si_3N_4$ ceramics produced by nitridation and post-sintering using semiconductor-waste-Si sludge were investigated. Lots of microcracks were observed in the waste-Si powders which contained some amounts of amorphous $SiO_2$. The nitridation rate of waste-Si compacts showed lower value than that of commercial Si powder compacts. The nitridation rate was increased with increasing nitridation temperature and then the percent of nitridation at 1470$^{\circ}C$ showed 98%. The phases of $Si_3N_4$ in the reaction-bonded bodies were mixed with ${\alpha}$ and ${\beta}$-type, and small amounts of $Si_2N_2O$ phase while those after post-sintering were ${\beta}$-$Si_3N_4$ and ${\alpha}$-Sialon. The sample post-sintered at 1950$^{\circ}C$ showed the fracture toughness of 5.6 $^MPa{\cdot}m^{1/2}$ and the fracture strength of 497 MPa which were lower than those of sintered body using commercial Si powder possibly due to the formation of ${\alpha}$-Sialon phase.

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Geochemical Characteristics and Heavy Metal Pollutions in the Surface Sediments of Gwangyang and Yeosu Bay, south coast of Korea (광양만 및 여수해만 표층퇴적물의 지화학적 특성과 중금속 오염)

  • 현상민;이태희;최진성;최동림;우한준
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.4
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    • pp.380-391
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    • 2003
  • Surface sediments were collected from Gwangyang and Yeosu Bays to evaluate their sedimentological characteristics and geochemical aspects of both the benthic environment and heavy metal pollution. The grain size distribution includes both sandy and muddy sediments. Sand-rich sediments occur mainly near the POSCO and the channel between Namhedo and Yeosu Bando, while elsewhere mud-dominated sediments are present. TOC content ranges from 0.2 to 2.1 % and C/N ratios indicate that the range arises from the mix of organic matter. The C/S ratios of this organic matter show that parts of the study area are anoxic or have sub-anoxic bottom conditions. The hydrogen sulfide content of the sediment has a range of 0.7 to 301 ppm, with a high content occurring inshore of Myodo Island, where it indicates a polluted environment. The enrichment factor (Ef) and index of accumulation rate (Igeo) of ten heavy metals (Co, Ni, Cu, Cd, Pb, Li, Zn, V, Cr, Ba) show that parts of the study area contain from one to seven times more Pb and Ba, and from 0.8 to 3.5 times more of the other elements than the mean sediment value. The Igeo values of V and Cd show that different parts of the area can be classified as heavily polluted, heavily to moderately polluted, or more or less unpolluted. Those areas that have both high levels of enrichment and high accumulation rates of heavy metals contain predominantly fine sediments with a high organic matter and hydrogen sulfide content.

The Changes of Solid, Nitrogen and Phosphorus Concentrations in Pig Slurry Stored at Various Depth of Slurry Storage Tank (돼지분뇨슬러리의 액비조내 저장깊이별 고형물 및 질소, 인의 함량분포에 관한 연구)

  • Jeong, Kwang-Hwa;Chung, Eui-Soo;Park, Chi-Ho;Kwag, Jung-Hoon;Choi, Dong-Yoon;Yoo, Yong-Hee
    • Journal of Animal Environmental Science
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    • v.12 no.3
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    • pp.161-168
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    • 2006
  • This paper describes the changes of characteristics of pig slurry according to storing depth. Most of the substances containing pollutants, such as were Management of manure and wastewater from animal confinement facilities is a critical factor for pollution control. With proper treatment processing method in both solid and liquid forms, it can be used as a fertilizer and soil conditioner. In Korea, liquid-manure handling system is very popular because its treatment and application is easy and labor saving. In the storage tank treatment, the period of fermentation process and solids-liquid separation averages six months and the supernatant liquid is being used as a fertilizer. In this study, the changes in chemical characteristics of pig slurry at varying depths of the storage tank were investigated. Results showed that the pH value of the fermented pig slurry was > 7, while the major pollutants such as BOD, SS, N and P were highest in the bottom of the tank. Therefore, the above findings proved that varying depths in the storage tank can influence the concentration of pollutants of the fermented pig slurry.

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Quality Characteristics of Muffin with Added Corni fructus Powder (산수유 분말 첨가 머핀의 품질특성)

  • Jeong, Ji-Suk;Kim, Yong-Joo;Choi, Bo-Rum;Lee, Jeong-Ae;Go, Geun-Bae;Son, Byeong-Gil;Gang, Suk-Won;An, Sang-Hee
    • Korean journal of food and cookery science
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    • v.30 no.6
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    • pp.726-734
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    • 2014
  • The purpose of this study was to examine the qualities of muffins made with 0, 2, 4, 6, and 8% Corni fructus powder. The height of the muffins did not significantly differ between the sample groups; however, the weight of the control group was higher than that of the test samples containing Corni fructus powder. The volume and specific loaf volume of muffins decreased with the addition of Corni fructus powder. The baking loss of the samples containing Corni fructus powder was also higher than that of the control group. The moisture content of the control group was 19.88%, whereas that of the test samples ranged from 16.72~21.01%. The pH of batters and muffins of the test samples were lower than those of the control group. For DPPH radical scavenging activity, the control group measured 11.46%, whereas the test samples ranged from 22.63~53.33%. The L and b values of the crust and crumbs decreased, but the a value was increased significantly by the addition of Corni fructus powder. Examination of the textural properties revealed the hardness, gumminess and brittleness of muffins containing Corni fructus powder were significantly higher than those of the control group. In term of overall preference, the sensory evaluation scores of groups containing 2% and 4% of Corni fructus powder did not show significant differences compared to the control group. Based on the above results, using Corni fructus powder at less than 4% would be appropriate for making muffins.

Analysis of Volatile Compounds in Kimchi-Flavored Steak Sauce (김치를 이용한 스테이크소스의 휘발성 향기성분)

  • Cho, Yong-Bum;Park, Woo-Po;Jung, Eun-Joo;Lee, Mi-Jeong;Lee, Yang-Bong
    • Korean Journal of Food Science and Technology
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    • v.34 no.3
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    • pp.351-355
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    • 2002
  • Volatile compounds of kimchi-flavored steak sauce were isolated using simultaneous steam distillation and solvent extraction methods and identified by matching mass spectrum and retention index (RI) with the reference data. Twenty-three compounds including five aldehydes, four alcohols, four acids, three sulfur-containing compounds, one ketone, and six others were identified, among which the most abundant compound was eugenol. Sulfides such as dimethyl dis- and trisulfides, and acids such as acetic and dodecanoic acids showed strong effects on the kimchi flavor. Aroma extract dilution analysis with three fold dilution factor shown in over the FD value 34 identified 2-butanal, 2-pentylfuran, methyl-2-propenyl disulfide, and 2-furanmethanol. Strong good aroma was detected in the RI range between 1030 and 1357, bad aroma in RI 1561, sweety aroma in RI 2057, clover aroma of eugenol in RI 2122, and rancid flavor in RI 2251.

Environmental Geochemistry and Heavy Matel Contamination of Ground and Surface Water, Soil and Sediment at the Kongjujuil Mine Creek, Korea (공주제일광산 수계에 분포하는 지하수, 지표수, 토양 및 퇴적물의 환경지구화학적 특성과 중금속 오염)

  • 이찬희
    • Economic and Environmental Geology
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    • v.32 no.6
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    • pp.611-631
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    • 1999
  • Enviromental geochemisty and heary metal contamination at the Kongjueil mine creek were underaken on the basis of physicohemical properties and mineralogy for various kinds of water (surface, mine and ground water),soil, precipitate and sediment collected of April and December in 1998. Hydrgeochemical composition of the water samples are characterized by relatively significant enricant of Ca+Na, alkiali ions $NO_3$ and Cl inground and surfore water, wheras the mine waters are relatively eneripheral water of the mining creek have the characteristics of the (Ca+Mg)-$(HCO_3+SO_4)$type. The pH of the mine water is high acidity (3.24)and high EC (613$\mu$S/cm)compared with those of surface and ground water. The range of $\delta$D and $\delta^{18}O$ values (relative to SMOW) in the waters are shpwn in -50.2 to -61.6% and -7.0 to -8.6$\textperthousand$(d value=5.8 to 8.7). Using computer program, saturation index of albite, calcite, dolomite in mine water are nearly saturated. The gibbiste, kaolinite and smectite are superaturated in the surface and ground water, respectively. Calculated water-mineral reaction and stabilities suggest that weathing of silicate minerals may be stable kaolinite owing to the continuous water-rock reaction. Geochemical modeling showed that mostly toxic heavy metals may exist larfely in the from of metal-sulfate $(MSO_4\;^2)$and free metal $(M^{2+})$ in nmine water. These metals in the ground and surface water could be formed of $CO_3$ and OH complex ions. The average enrichment indices of water samples are 2.72 of the groundwater, 2.26 of the surface water and 14.15 of the acid mine water, normalizing by surface water composition at the non-mining creek, repectively. Characteristics of some major, minor and rate earth elements (Al/Na, K/Na, V/Ni, Cr/V, Ni/Co, La/Ce, Th/Yb, $La_N/Yb_N$, Co/Th, La/Sc and Sc/Th) in soil and sediment are revealed a narrow range and homogeneous compositions may be explained by acidic to intermediate igneous rocks. And these suggested that sediment source of host granitic gneiss colud be due to rocks of high grade metamorphism originated by sedimentary rocks. Maximum concentrations of environmentally toxic elements in sediment and soil are Fe=53.80 wt.% As=660, Cd=4, Cr=175, Cu=158, Mn=1010, Pb=2933, Sb=4 and Zn=3740 ppm, and extremely high concentrations are found are found in the subsurface soil near the ore dump and precipitates. Normalizing by composition of host granitic gneiss, the average enerichment indices are 3.72 of the sediments, 3.48 of the soils, 10.40 of the precipitates of acid mine drainage and 6.25 of the soils near the main adit. The level of enerichment was very severe in mining drainage sediments, while it was not so great in the soils. mineral composition of soil and sediment near the mining area were partly variable being composed of quartz, mica, feldspar, chlorite, vermiculite, bethierin and clay minerals. reddish variable being composed of quartz, mica, feldspar, chlorite, vermiculite, bethierin and clay minerals. Reddish brown precipitation mineral in the acid mine drainage identifies by schwertmanite. From the separated mineralgy, soil and sediment are composed of some pyrite, arsenopyite, chalcopyrite, sphalerite, galena, malachite, goethite and various kinds of hydroxied minerals.

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The Number of Nucleotide Substitutions per Sites of Mitochondrial DNA in the Four Pleuronectid Species (미토콘드리아 DNA에 의한 붕넙치과 어류 4종간의 염기치환수)

  • PARK Jung-Youn;KIM Yoon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.5
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    • pp.649-658
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    • 1995
  • In order to estimate the level of genetic differences among the pleuronectid species, mitochondrial DNAs were isolated from four species: brown sole, Limanda herensteini; marbled sole, Limanda Yokohamae; stone flounder, Kareius bicoloratus; starry flounder, Platichthys stellatus, and the number of nucleotide substitutions was calculated by the restriction fragment length polymorphisms (RFIPs) generated by f4 sin base recognition restriction endonucleases. Total lengths of the mitochondrial DNA were measured as about 17.6 kbp in all species. Ten different composite genotypes were observed in brown sole, four different genotypes in marbled sole, and two different genotypes in starry flounder. However, only one genotype was observed in stone flounder. The calculated haplotypic diversity value of brown sole was higher than that of marbled sole. The average number of nucleotide substitutions per sites in four species was estimated to be 0.0045 in the intraspecies, 0.0344 in the interspecies, and 0.0457 in the genera, respectively. From these results, we could estimate that the genetic differences among interspecies were not influenced by nucleotide substitutions but genetical discontinuous.

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