• Title/Summary/Keyword: bed form

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Performance Enhancement of Anaerobic Treatment of Waste Sludge by Chemical Pretreatment (화학적 전처리를 통한 혐기성 슬러지 처리효율의 향상)

  • 허준무;박종안;손부순
    • Journal of environmental and Sanitary engineering
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    • v.13 no.1
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    • pp.16-25
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    • 1998
  • Laboratory-scale experiment using anaerobic fluidized bed reactor was carried out to investigate the prehydrolysis step with caustic soda on the treatment efficiency of anaerobic sludge treatment, since the overall rate-limiting step for the complete anaerobic digestion of sludge was the hydrolysis step by extracellular bacterial enzymes of insoluble polymeric molecules. Reactors received a sludge which had not been pretreated, a 50-50 mixture of pretreated and untreated sludge, and the fully pretreated sludge. Hydraulic retention time of 10, 5, 2.5 days and 1 day were applied with an respective equivalent organic loading rate of 1.17, 2.23, 4.17, 11.24 gCOD/L/d. Reactor with the untreated sludge did not archieve adequate digestion even at the HRT of 5 days, and reactor, which received the 50-50 mixture, operated well at the HRT of 5 days, but began to show signs of unstable digestion at the HRT of 2.5 days. While, reactor, which was fed the hydrolyzed sludge, operated reasonably well at the 2.5 days, but was showing somewhat decrease in removal efficiencies. Results, therefore, have substantiated that the limiting reaction in the anaerobic treatment process is hydrolysis. The soluble COD did not significantly accumulate in the reactor as organic acid form, even when they were highly stressed. It was believed that this resistance to a build-up of organic acids and soluble COD behavior was mainly due to the maintenance of the methane bacteria in the fixed-film system which prevents washout as the organic loading increased. The anaerobic fluidized bed reactor was therefore effective for the digestion of waste activated sludge at short HRT.

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A STUDY ON ADSORPTION AND DESORPTION BEHAVIORS OF 14C FROM A MIXED BED RESIN

  • Park, Seung-Chul;Cho, Hang-Rae;Lee, Ji-Hoon;Yang, Ho-Yeon;Yang, O-Bong
    • Nuclear Engineering and Technology
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    • v.46 no.6
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    • pp.847-856
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    • 2014
  • Spent resin waste containing a high concentration of $^{14}C$ radionuclide cannot be disposed of directly. A fundamental study on selective $^{14}C$ stripping, especially from the IRN-150 mixed bed resin, was carried out. In single ion-exchange equilibrium isotherm experiments, the ion adsorption capacity of the fresh resin for non-radioactive $HCO_3{^-}$ ion, as the chemical form of $^{14}C$, was evaluated as 11mg-C/g-resin. Adsorption affinity of anions to the resin was derived in order of $NO_3{^-}$ > $HCO_3{^-}{\geq}H_2PO_4{^-}$. Thus the competitive adsorption affinity of $NO_3{^-}$ ion in binary systems appeared far higher than that of $HCO_3{^-}$ or $H_2PO_4{^-}$, and the selective desorption of $HCO_3{^-}$ from the resin was very effective. On one hand, the affinity of $Co^{2+}$ and $Cs^+$ for the resin remained relatively higher than that of other cations in the same stripping solution. Desorption of $Cs^+$ was minimized when the summation of the metal ions in the spent resin and the other cations in solution was near saturation and the pH value was maintained above 4.5. Among the various solutions tested, from the view-point of the simple second waste process, $NH_4H_2PO_4$ solution was preferable for the stripping of $^{14}C$ from the spent resin.

Immunocytochemical Localization Qf raf Protein Kinase in Cerebrum of Geoclemys reevesii (Gray) (남생이(Geoclemys reevesii) 대뇌에 있어서 raf Protein Kinase의 면역세포화학적 분포)

  • 최원철;문현근
    • The Korean Journal of Zoology
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    • v.33 no.2
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    • pp.141-151
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    • 1990
  • Raf protein kinases and protein kinase C belong to serine/threonine-specific proteins in the cytoplasin, and are similar to each other in functional structure and the aspect of the distribution of celI. The distribution of raf protein kinase in the cerebrum of Geoclemys reevesfi as studied by using the antibodies against a-raf and c-raf protein kinase which induce the expression of raf fainily oncogenes. In general, raf protein kinases were distributed in such restricted regions as the general pallium, hippocampal formation, pdmordiuin hippocampi,nucleus of lateral olfactory tract, basal amygdaloid nucleus, and bed of stria terminalis. Immunological labeling of c-raf protein kinase was more widespread than that of a-raf. However, the intensity of the labeling of c-raf was lower than that of a-raf. The spherical cells of basal amygdaloid nucleus is a ring-like form, because only the cytoplasm was imunolabeled. Especially, c-raf protein kinase occurred in the cells which contained protein kinase C abundandy such as pyramidal cells and Purkinje cells. This suggests that a- and e-raf protein kinases may synegistically induce carclnoma with myc gene which is activated by protein kinase C.

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An Analysis on Preference of Interior Coordination Elements for Urban Small Housing - Focused on Gold-Generation(Gold Miss, Gold Mr.) - (도시형 소형주택의 실내코디네이션 요소 선호 분석 - 골드세대(골드미스, 골드미스터) 수요자를 중심으로 -)

  • Kim, So-Hee;Han, Young-Ho
    • Korean Institute of Interior Design Journal
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    • v.21 no.5
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    • pp.264-271
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    • 2012
  • As changed population structure variously, population decrease is one of the important problem in present urbanization. It resulted decline of the medium-large size housings that increasing of 1-2 person household need the variety of small housing with housing type. This study was researched the Gold-Generation on theme by Gold Miss, Gold Mr. who preferring urban small housings that it analyzed survey of Gold generation who be wanted urban small housing by interior coordination elements. Data to be analyzed that first, Gold Mr. and Miss are preferred two bedroom applied by spatial structure coordination. Especially it is based on the separation between livingroom and bedroom with duplex type which is bathroom formed single unit type(shower/toilet/basin). In interior coordination of spatial elements, Gold Mr. considered the form of kitchen with huge ㄷ type instead of Gold Miss are preferred alpha room or alpha space to use powder room or dress room. Second, In Preference of interior coordination elements, Gold Mr. and Miss are preferred bed-clothes and curtains by fabrics, lighting are hanging and spot lighting, accessories are carpet with rug and porcelains. Color are preferred bright scheme both white and ivory, however preference of furniture is different from Gold Mr. and Gold Miss that Gold Mr. are ordered desk, sofa and shelves but Gold Miss are preferred sofa, bed, and dressing table. It showed between Gold Mr. and Gold Miss are equal needs or differences. It expects the basic research for understanding the interior coordination elements for preference in urban small housing as focused on Gold generation(Gold Miss, Gold Mr.) that they will be applied the interior space on urban small housing.

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Origin of Carbonate Flat Pebble Conglomerate of the Upper Cambrian Hwajǒl Formation, Chosǒn Supergroup, Korea (조선루층군(朝鮮累層群) 상부 캠브리아계(系) 화절층(花折層)에 협재(挾在)된 Carbonate Flat Pebble Conglomerate의 성인(成因))

  • Park, Byong-Kwon;Han, Sang-Joon
    • Economic and Environmental Geology
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    • v.18 no.2
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    • pp.177-184
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    • 1985
  • The carbonate flat pebble conglomerates (CFPC) are interbedded as lenticular bed in the greenish rhythmite of the upper part of $Hwaj{\check{o}}l$ Formation, $Jos{\check{o}}n$ Supergroup. Pebbles are composed mainly of lime-mudstone with small amounts of bioclasts and silt-sized subangular quartz grains. The matrix among pebbles is composed mainly of sparry calcite with relatively much amounts of bioclasts, silt-sized subangular quartz grains and authigenic pyrite crystals or grains. The sparry calcite of the matrix seems to be the results of neomorphism of skeletal sands and bioclasts. The pebbles are well rounded and no plastic deformations are found. Some pebbles show the outer rim of glauconite. CFPC are not associated with any other intertidal features such as stromatolites, flaser bedding and channel structures. Also any features indicative of subaerial exposure such as dessication cracks, fenestrae and so on are not found in the bed. The sedimentological features of CFPC suggest that the following conditions appear to have been necessary for the formation of CFPC : 1) episodic deposition of thin, permeable calcareous beds separated argillaceous beds; 2) preservation of these beds near the sediment-water interface where they could become rapidly cemented; 3) erosion and redeposition of the partially lithified beds by storms or other exceptional erosional events. Eventually storm erosion and redeposition together represent only one of several critical conditions in the genesis of CFPC. The CFPC are very common in Cambrian and lower Ordovician formations, and become very rare in the younger carbonate formations. The expansion of infauna after Ordovician Period eliminated the widespread potential for rapid submarine cementation which is one of the critical factors to form CFPC.

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A study on waterfall classification by form and processes (폭포의 지형학적 분류에 관한 연구)

  • PARK, Kyeong;KIM, Ji Young
    • Journal of The Geomorphological Association of Korea
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    • v.21 no.4
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    • pp.85-96
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    • 2014
  • A waterfall is a channel unit with steep bedrock. No strict criteria for height, water volume, gradient to define waterfalls exist in Korea. The goal of our study is to classify waterfalls based on morphological forms which are the outcomes of developmental processes. The genesis of waterfall depends upon erosional properties of waterfall. The height, gradient, bedrock strength and stream power of waterfalls are regarded as the main factors, by which waterfalls can be classified. We find out that the most important factor for the development of waterfalls is joint system. Development of joint system varies depending on bedrocks. Flow directions and erosional types are decided by the density and direction of joint system in the bedrock, which also decide the height and gradient of stream bed. Joint type decides the gradients of the bed, gradient and height of waterfalls, therefore, decides morphological forms.

Towards Reinterpretation of Korean Living Behavior: New Design Approach to Spatial Furniture (생활 문화 기반의 재해석 : 공간형 가구의 새로운 접근)

  • Jun, Kye Han;Choi, Kyung Ran
    • Korea Science and Art Forum
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    • v.27
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    • pp.213-219
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    • 2017
  • This paper aims to approach a spatial furniture for sedentary lifestyle which been has derived and evolved from Korea's traditional 'Ondol' heating system. In this living culture, people has been staid on the floor where people would sit directly on without furniture such as chair and bed. With every changing technological advances, sedentary life culture is transformed and mixed instead of sedentary habit. Most of people lived in western house such as apartment forms. As time go by, western furnitures were used became widespread. However, during the process, it impossible to acclimate ourselves to the new lifestyle such as chair, bed etc. This leads to users feeling uncomfortable on certain points. The researcher suggests a spatial furniture through a new approach to rest-taking that also intersects the cultures of East and West while resolving the a fore-mentioned issues. The study is conducted as follows. Firstly, issues are discovered through a user's lifestyle to exist usage and interplay of house and furniture. Furthermore, the issues was not a fragmentary thing but more related to a culture and a coustom of long standing. Secondly, a design experiment is conducted to conclude a new form and function that is better fit for the Korean culture where sitting on the floor is the norm. New direction for space that intersects the cultures of the East and West while using modules made convenient for contemporary life is presented. Finally, this study is meaningful in that it reinterprets furniture used for rest within the context of sedentary culture, in order to propose a new direction and value for design that overcomes the boundaries between eastern and western applied to resting space.

SPECIES OF CULTIVATED PORPHYRA IN KOREA (한국산 양식김의 종류)

  • KANG Jae Won
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.3 no.2
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    • pp.77-92
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    • 1970
  • Ueda, in the course of his systematic work on the lavers, Porphyra, in Japan and Korea in 1932, mentioned that most of the cultivated Porphyra belong to Porphyra tenera Kjellman. Then he, dividing the species into two forms, f. typica and f. kjellmani, put Korean cultivated Porphyra under the latter. From the 1930s to the early 1940s, Fujikawa, Kaneko and others worked on Physiological experiments or cultivational experiments of Porphyra in the culture-bed, but there was no mention about the cultivated Porphyra species. However, many fishermen generally recognize that the characteristics of cultivated Porphyra vary depending on their habitat or the picking season, and it is considered that these differences are due to the varieties of the species which are well adaptable to various environments. Recently, I have become aware of the predominant occurrence of P. yezoensis Ueda in most culture-beds of Korea as in the Tokyo Bay or other places in Japan. At present, since artificial seeding for the cultivation of Porphyra with Conchocelis has been carried out and peculiar species can be cultured, a study of the species of cultivated Porphyra has become an important subject. I collected the specimens from a number of culture-beds which are located in the legions shown in fig. 1 from January, 1968 to May, 1970 and found that there are five species, P. tenera Kjellman, P. yezoensis Ueda, P. kuniedai Kurogi, P. seriata Kjellman and P. suborbiculata Kjellman. Among them, P. kuniedai was treated as a round-type, a form of P. tenera, by Kunieda (1939) and Tanaka (1952) and the occurrence of this form is generally recognized by most fishermen. At present, as mentioned above, the most dominant species of cultivated Porphyra is P. yezoensis but the cultivation of P. tenera is restricted to certain culture-beds or the early half of the cultivation period. P. kunieda appears as a mixed species throughout most of the culture-beds, particulary in the later half of the period, while when it was picked in January it appeared dominantly in a place such as Gum-Dang where the 'Bal', splitted bamboo piece mat, was settled during the last of September. This is the first seeding process. The latter two species, P. suborbiculata and P. seriata appear frequently but in small amounts in the later half of the period particulary in the western region of the southern coast. However, it can not be ascertained when P. yezoensis becomes predominant, because specimens have not been available up until recent years but the process can be described as follows: We commonly recognize the ecological characteristics of P. tenera as follows; First, the conchospores of the species develop earlier and the period of its discharge is shorter than those of P. yezoensis; second, the microscopical buds discharge neutral spores which develop into new buds directly and buds develop repeatedly through a short period. Consequently, according to such above ecological characteristics, the species can grow thick on the 'Bal' exclusively. However, buds may disappear when they are harmed by disease such a 'infection by certain parasites or by other unusual environmental conditions. Thus P. yezoensis are enabled to grow on the 'Bal' instead of the former species since they not only develop later than the former but also macroscopical fronds discharge the neutral spore throughout the period from October to May. Likewise, if any disease appears in the culture-bed ill the later half of the period, the former is more severely damaged than the latter because the former have less resistance to the disease than the latter. Thus fewer frond survive and fewer carpospores which are the origin of the next generation can be discharged. However the latter by their nature can continue growing until early summer. In the case of the culture-bed where the above phenomenon occurs repeatedly P. yezoensis gradually may become the dominant species among cultivated Porphyra. In support of the validity of this process we find that according to the description and the plate of Wada (1941), P. tenera, P. yezoensis and P. kuniedai grow together in the culture-bed at the mouth of the Nakdong River where P. yezoensis occurs predominantly and mixed with P. kuniedai.

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An Analysis of Fall Incidence Rate and Its Related Factors of Fall in Inpatients (입원환자 낙상 발생 실태와 원인에 관한 분석 연구)

  • Kim, Chul-Gyu;Suh, Moon-Ja
    • Quality Improvement in Health Care
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    • v.9 no.2
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    • pp.210-228
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    • 2002
  • Background: The purpose of this research was to examine the fall incidence rate and its related factors of fall in inpatients. Methods: The data were collected from the 138 fall incident reports in one tertiary hospital in Seoul from April 1st 1999 to September 30th 2001. The Fall Incident Report Form was originally developed based on that of Massachusetts General Hospital revised in 1995. And this was modified for this survey by the collaborating work of QI team including researcher and department of nursing service of this particular hospital. The contents of Fall Incident Form were general characteristics of patient. factors related to fall. types and places of fall. circumstances, nursing interventions. and outcome. Results: 1) The incidence rate of fall was 0.08% of total discharged patients and 0.081 per 1000 patient-day. This incidence rate is much lower than that of several hospitals in USA. This finding might result from the different incidence report system of each hospital. 2) The characteristics of fall-prone patient were found as follows. They were mostly over 60 years old, in alert mental status, ambulatory with some assistance, and dependent on ambulatory device. The types of diseases related high incidence rate were cerebrovascular disease(3.2), hypertension(1.6), cardiovascular disease(1.4), diabetes(1.3) and liver disease(0.6). 3) The majority of fall events usually occurred m bed. bedside(walking or standing) and bathroom in patient room. Usually they were up on their own when they fell. And there were more falls of elderly occurred during night time than day or evening. 4) 63.8% of fall events resulted in physical injuries such as fracture and usually the patients had diagnostic procedures and some treatment(ex. suture) which caused additional cost to the patients and their families. 5) The found risk factors of fall were drugs(antihypertensive drug, diuretics) and environmental factors like too high bed height, long distance of bedside table and lamp switch, and slippery tile of bathroom floor. Conclusion: Considering these results, every medical and nursing staff should be aware of the risk factors of patients in hospital, and should intervene more actively the preventive managements, specially for the elderly patients during night. Therefore, it is recommended that the development of Fall Prevention Programs based on these results.

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Propagation Analysis of Dam Break Wave using Approximate Riemann solver (Riemann 해법을 이용한 댐 붕괴파의 전파 해석)

  • Kim, Byung Hyun;Han, Kun Yeon;Ahn, Ki Hong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.5B
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    • pp.429-439
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    • 2009
  • When Catastrophic extreme flood occurs due to dam break, the response time for flood warning is much shorter than for natural floods. Numerical models can be powerful tools to predict behaviors in flood wave propagation and to provide the information about the flooded area, wave front arrival time and water depth and so on. But flood wave propagation due to dam break can be a process of difficult mathematical characterization since the flood wave includes discontinuous flow and dry bed propagation. Nevertheless, a lot of numerical models using finite volume method have been recently developed to simulate flood inundation due to dam break. As Finite volume methods are based on the integral form of the conservation equations, finite volume model can easily capture discontinuous flows and shock wave. In this study the numerical model using Riemann approximate solvers and finite volume method applied to the conservative form for two-dimensional shallow water equation was developed. The MUSCL scheme with surface gradient method for reconstruction of conservation variables in continuity and momentum equations is used in the predictor-corrector procedure and the scheme is second order accurate both in space and time. The developed finite volume model is applied to 2D partial dam break flows and dam break flows with triangular bump and validated by comparing numerical solution with laboratory measurements data and other researcher's data.