• Title/Summary/Keyword: Shared Surface

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Competition of Sulfate for Sorption Sites of Cecil Bt Soil in Binary Anion System (2중 음이온 체계내에서 시슬 Bt토양의 흡착부위에 대한 황산이온의 경쟁)

  • Chung, Doug Young
    • Korean Journal of Agricultural Science
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    • v.23 no.2
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    • pp.250-260
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    • 1996
  • Observed results of the adsorption between two competing anions for the shared sorption sites represent that the adsorption phenomena may depends on the characteristics of anion and available sorption sites in a given conditions. In binary systems, adsorption of one species can significantly influence the fate of the other anion, resulting in control of the extent of solute-adsorbate distributions throughout soil profile. And the proton-donation mechanisms by organic anions having a carboxyl as a functional group can also influence the adsorption of inorganic anions onto the hydroxylated sites of Fe and Al oxides. However, study of competitive adsorption of specifically adsorbed anions illustrates some of difficulties which arise in interpretation of reactions at oxide/aqueous solution interfaces. At least two factors prevented a simple analysis of reactions. First, at any pH value the maximum amount of adsorbate taken up at the surface depends on the identity of the anion. Second, it was necessary to postulate the sorption sites where the anion can be adsorbed. Hence, anions having non-specific adsorption characteristics are less capable for sorption sites, compared to those of specific adsorption characteristics, even though competition complies both ordinary and electrostatic interactions for sorption sites. Therefore, competition among chemical species in soil matrix can be of major significance in determining the effective mobility of any reactive anions with sorption sites.

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The Impact of Supertall Density on City Systems

  • Price, Bill;Bickerdyke, Andrew;Borchers, Meike;Gabbitas, Tim;Hailey, Lee
    • International Journal of High-Rise Buildings
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    • v.6 no.4
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    • pp.327-332
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    • 2017
  • This paper discusses several topics associated with the densification caused by supertall buildings and their impact on city systems. The paper covers five key areas where a supertall tower creates a concentration of needs and effects. First, the paper comments on population shifts towards the city and how they affect carbon footprint, utilities infrastructure and transport. The effect of single- and mixed-use towers is discussed in the context of population density. The second section brings the issues of transit, accessibility and master planning into focus. The use and criticality of public transport, cycling and walking is described. Servicing and deliveries using freight consolidation and shared systems is also discussed along with their contribution to the culture of sustainable travel. In the third section the paper reflects on supertall buildings' below-ground utilities and drainage provision, particularly the challenges faced in established city infrastructures. The utilities issues associated with supertall concentration (in land-use terms) compared to equivalent low-rise distribution is also commented on in the context of surface water runoff. In the fourth section, the topic of supertall sustainability is discussed and how city systems need to respond to create desirable and affordable space for occupiers. The changing need for vertical communities, 'stacked neighbourhoods' and the notion of a micro-city is described. Finally, the paper considers the energy consumption and resilience of supertall buildings in the context of basic geometry, façade design, climate and mixed-use benefits as they impact city systems.

Development of a Hydraulic Level Control System for High-speed Rice Transplanting Machines (고속 이앙기의 유압 수평 제어 장치 개발에 관한 연구)

  • 정연근;정병학;김경욱
    • Journal of Biosystems Engineering
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    • v.27 no.2
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    • pp.79-88
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    • 2002
  • This study was conducted to develop system for high speed rice transplanting machines. The control system includes a sensor detecting the tilt angle of the seedling bed, a micro-controller and a hydraulic system consisting of a double acting cylinder, a four-way three-position solenoid valve, a relief valve and a hydraulic pump. The levelling system shared the pump with the existing steering control, resulting in a tandem center circuit for the steering and levelling control systems. Using the input signal from the sensor, the micro-controller determined and generated the output signal to control the cylinder through the solenoid valve to keep the seedling bed always parallel to the water surface regardless of soil unevenness during the transplanting operations. Both an ON/OFF and a PWM control schemes were tested. When the flow rate was more than 1 ι/min in the ON/OFF control, the system showed unstable rolling. However, in the PWM control, the system worked stably although the flow rate was more than 1 ι/min. The PWM control showed a better performance when a large difference between the angle and the dead band of the control system occurred. The characteristics of tile system response to given tilt angles were predicted by a computer simulation. Both the ON/OFF and the PWM control systems worked well providing that the operating and waiting times were properly adjusted.

Intermittent chlorination shifts the marine biofilm population on reverse osmosis membranes

  • Jeong, Dawoon;Lee, Chang-Ha;Lee, Seockheon;Bae, Hyokwan
    • Membrane and Water Treatment
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    • v.10 no.6
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    • pp.395-404
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    • 2019
  • The influence of chlorine on marine bacterial communities was examined in this study. A non-chlorine-adapted marine bacterial community (NCAM) and a chlorine-adapted bacterial community (CAM, bacterial community treated with $0.2mg-Cl_2/L$ chlorine) were cultivated for 1 month. A distinct difference was observed between the NCAM and CAM, which shared only eight operational taxonomic units (OTUs), corresponding to 13.1% of the total number of identified OTUs. This result suggested that chlorine was responsible for the changes in the marine bacterial communities. Kordiimonas aquimaris was found to be a chlorine-resistant marine bacterium. The effect of intermittent chlorination on the two marine biofilm communities formed on the reverse osmosis (RO) membrane surface was investigated using various chlorine concentrations (0, 0.2, 0.4, 0.6 and 0.8 mg $Cl_2/L$). Although the average number of adherent marine bacteria on the RO membrane over a period of 7 weeks decreased with increasing chlorine concentration, disinfection efficiencies showed substantial fluctuations throughout the experiment. This is due to chlorine depletion that occurs during intermittent chlorination. These results suggest that intermittent chlorination is not an effective disinfection strategy to control biofilm formation.

Biodiversity and Enzyme Activity of Marine Fungi with 28 New Records from the Tropical Coastal Ecosystems in Vietnam

  • Pham, Thu Thuy;Dinh, Khuong V.;Nguyen, Van Duy
    • Mycobiology
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    • v.49 no.6
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    • pp.559-581
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    • 2021
  • The coastal marine ecosystems of Vietnam are one of the global biodiversity hotspots, but the biodiversity of marine fungi is not well known. To fill this major gap of knowledge, we assessed the genetic diversity (ITS sequence) of 75 fungal strains isolated from 11 surface coastal marine and deeper waters in Nha Trang Bay and Van Phong Bay using a culture-dependent approach and 5 OTUs (Operational Taxonomic Units) of fungi in three representative sampling sites using next-generation sequencing. The results from both approaches shared similar fungal taxonomy to the most abundant phylum (Ascomycota), genera (Candida and Aspergillus) and species (Candida blankii) but were different at less common taxa. Culturable fungal strains in this study belong to 3 phyla, 5 subdivisions, 7 classes, 12 orders, 17 families, 22 genera and at least 40 species, of which 29 species have been identified and several species are likely novel. Among identified species, 12 and 28 are new records in global and Vietnamese marine areas, respectively. The analysis of enzyme activity and the checklist of trophic mode and guild assignment provided valuable additional biological information and suggested the ecological function of planktonic fungi in the marine food web. This is the largest dataset of marine fungal biodiversity on morphology, phylogeny and enzyme activity in the tropical coastal ecosystems of Vietnam and Southeast Asia. Biogeographic aspects, ecological factors and human impact may structure mycoplankton communities in such aquatic habitats.

Histological study on the skin structure in two mudskippers, Periophthalmus waltoni and Boleophthalmus dussumieri in relation to their terrestrial life

  • Mehran Dorostghoal;Ashraf Jazayeri;Sara Ashiri
    • Applied Microscopy
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    • v.52
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    • pp.13.1-13.6
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    • 2022
  • Microscopic structure of skin in two amphibious mudskipper fish; Boleophthalmus dussumieri Valenciennes, 1837 (B. dussumeri) and Periophthalmus waltoni Koumans, 1941 (P. waltoni) were investigated in relation to their lifestyle. The general structure of skin is the same among the two species. Epidermis in B. dussumeri was thicker significantly than P. waltoni. The dermal bulges were only well developed in the skin of B. dussumeri. Mucous cells were absent in the epidermis of P. waltoni but present in B. dussumeri. Both B. dussumeri and P. waltoni have well-developed swollen middle cells as a shared epidermal feature. The thickness of the middle cell layer of the epidermis in B. dussumeri was significantly greater than in P. waltoni. Capillaries in the dorsal and ventral parts of the body are more closely distributed to the epidermal surface in P. waltoni than in B. dussumeri. The diffusion distance in the dorsal epidermis of P. waltoni was less than that in the ventral epidermis of B. dussumeri. A comparative examination of the skin of mudskipper species suggests that, due to the more terrestrial lifestyle adopted by P. waltoni, the skin contributes more to respiration.

A Study on the Rectangular-Shaped Passive Row Piles in Inclined Sand-Ground by Model Test (경사모래지반의 사각형 수동 열말뚝에 관한 실험적 연구)

  • Bae, Jong-Soon;Kim, Ji-Seong;Kwon, Min-Jae
    • Journal of the Korean Geotechnical Society
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    • v.25 no.11
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    • pp.39-51
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    • 2009
  • This is a study on rectangular-shaped passive row piles in inclined sand-ground by model tests. The experiment controlled the angle of inclination of ground and induced the ground destruction. We also measured the behavior of row piles, by adjusting the shape, position and spacing of piles. As a result, we confirmed the earth pressure, the lateral resistance, and the effect of depressing on the ground variation working on passive pile. The effect of B-type pile of which the front width is wide is bigger than that of H-type pile of which the side width is wide. We can find out the failure angle of slope, the shared force of pile and soil by using the lateral resistance graph based on slope angle.

Impacts of Carbon Neutrality and Air Quality Control on Near-term Climate Change in East Asia (탄소중립과 대기질 개선 정책이 동아시아 근 미래 기후변화에 미치는 영향)

  • Youn-Ah Kim;Jung Choi;Seok-Woo Son
    • Atmosphere
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    • v.33 no.5
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    • pp.505-517
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    • 2023
  • This study investigates the impacts of carbon neutrality and air quality control policies on near-term climate change in East Asia, by examining three Shared Socioeconomic Pathways (SSPs) scenarios from five climate models. Specifically, low carbon and strong air quality control scenario (SSP1-1.9), high carbon and weak air quality control scenario (SSP3-7.0), and high carbon and strong air quality control scenario (SSP3-7.0-lowNTCF) are compared. For these scenarios, the near-term climate (2045-2054 average) changes are evaluated for surface air temperature (SAT), hot temperature extreme intensity (TXx), and hot temperature extreme frequency (TX90p). In all three scenarios, SAT, TXx, and TX90p are projected to increase in East Asia, while carbon neutrality reduces the increasing rate of SAT and hot temperature extremes. Air quality control strengthens the warming rate. These opposed mitigation effects are robustly forced in all model simulations. Nonetheless, the impact of carbon neutrality overcomes the impact of air quality control. These results suggest that fast carbon neutrality, more effective than an air quality control policy, is necessary to slowdown future warming trend in East Asia.

Teaching Architectural Design in Post-War America - Gyorgy Kepes' Basic Course at MIT's Department of Architecture - (20세기 후반 MIT의 건축설계 교육과 기요르기 케피쉬의 기초디자인 프로그램의 특성과 변화에 관한 연구)

  • Pai, Hyung-Min
    • Journal of architectural history
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    • v.15 no.2
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    • pp.39-54
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    • 2006
  • Focusing on the emergence of the basic course in American schools of architecture, in particular Gyorgy Kepes' courses at MIT, this paper studies the transformation of architectural pedagogy during the years after World War II. Kepes centered his architectural pedagogy on the picture plane, which was to function as the primary media for applying the principles of Gestalt psychology, that is the identification of the whole and its parts and the reciprocity between the internal human organism and the outside world. Kepes hence introduced a set of unconventional visual practices that were not readily assimilated to architectural conventions. Paralleling the establishment of the basic course, MIT also formulated a functionalist and spatial pedagogy with its two initial design studios, courses 4.721 and 4.722. These studios shared the notion that architectural design evolved from the inside toward the outside, an idea that took hold not just in the pragmatic environment of MIT's studios but also in conservative academic programs as well as in popular magazines, picture books, and exhibitions for the consumer public. The architectural surface became inseparable from the objects of art, furniture, and design, all of which were to be the generators of space. Hence, during the 1950s, the architectural surface provided a specific locus of intersection between the visual fundamentals of the basic course and the working principles of architectural design. Kepes, however, had by this time become disillusioned with architecture's potential as the medium of unity. Though he maintained the Gestalt logic of identity, he expanded it toward the goal of grander synthesis of society and consciousness freeing himself from the constraints of disciplinary instruction. In the case of Kepes, the mediating role of the picture plane was foregone in a regressive turn toward a primal, innocent, and direct experience.

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A Study on Visual Attention on Color Perception by Visitors of Children's Hospital (어린이병원 방문자의 색채지각에 나타난 시각적 주의에 관한 연구)

  • Cho, Eun-Kil;Son, Kwang-Ho
    • Korean Institute of Interior Design Journal
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    • v.25 no.2
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    • pp.50-58
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    • 2016
  • The design of children's hospitals is highly dependent on color schemes. As a space shared together by both adults and children, the design of children's hospitals require color coordination that takes account of the users' characteristics. Visual perception tracking experiment was conducted on the 2 chosen experimental images with a target group made up of adults and children, the following results were found. First, visual attention characteristics of spatial elements' colors were found. The contrast of colors were discovered to effect attention, especially the information desk region showed highest attention. Pillars are subjected to a higher attention relative to other spatial elements, it is suggested when using accent colors to use it only when it is absolutely necessary in partial areas. In contrast, floor patterns were found to be subjected to very low attention relative to other elements. Second, effects of color contrast on visual attention were uncovered. Although color contrast effects attention for both adults and children, children were found to be more effected by color contrast than adults. Especially, children's tendency to rely on color contrast for visual recognition was higher than adults. Since when using only one type on a wide surface children show higher attention on the < vivid > colors than adults, when planning a color coordination for children using < pale > colors instead of < vivid > ones in background for a large surface is seen as a more desired method to increase attention by putting emphasis on the [sharply contrasting] colors.