• 제목/요약/키워드: bed form

검색결과 265건 처리시간 0.025초

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

  • 허준무;박종안;손부순
    • 환경위생공학
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    • 제13권1호
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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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    • 제46권6호
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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.

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

  • 최원철;문현근
    • 한국동물학회지
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    • 제33권2호
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    • pp.141-151
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    • 1990
  • Raf protein kinases and protein kinase C는 세포질내 serine/threonine-specific protein에 속한다. 그리고 기능적인 구조와 세포내의 분포 양상은 서로 비슷하다. Raf family oncogene를 발현시키는 a-raf와 c-raf protein kinase에 대한 antibodies로써 남생이 대뇌의 raf protein kinase의 분포를 조사하였다. 일반적으로 raf protein kinase는 제한된 지역에서 즉,general pallium,hippocampal formation, pdmordiuin hippocampi,nucleus of lateral olfactory tract, basal amygdaloid nucleus와bed of stria terminalis에 나타났으며, c-raf protein kinase의 면역학적 labeling은 a-raf보다 그 범위가 넓었다. 그렇지만 labeling되는 intensity는 오히려 a-raf보다 낮았다. 그런데 a-raf에서 가장 명확한 좋은 예는 basal amygdaloid nucleus내의 구형모양의 세포인데, 이 세포는 세포질이 매우 강하게 labeling되어 지므로 ring모양과 같이 나타났다. 특히 c-raf는 protein kinase C 가 많이 나타나는 pyramidal 세포나 Purkinje세포에 많이 존재하는 것을 볼 때 protein kinase에 의하여 활성화되는 myc와 서로 상협작용을 유도한다고 제안하는 바이다.

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

  • 김소희;한영호
    • 한국실내디자인학회논문집
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    • 제21권5호
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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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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) (Origin of Carbonate Flat Pebble Conglomerate of the Upper Cambrian Hwajǒl Formation, Chosǒn Supergroup, Korea)

  • 박병권;한상준
    • 자원환경지질
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    • 제18권2호
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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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폭포의 지형학적 분류에 관한 연구 (A study on waterfall classification by form and processes)

  • 박경;김지영
    • 한국지형학회지
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    • 제21권4호
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    • pp.85-96
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    • 2014
  • 폭포는 하나의 하천단위이며 기반암하상의 종단면이 급경사인 지점에 물이 흐르는 것으로 아직까지 폭포에 대한 절대적인 높이, 경사, 유량에 대한 기준은 없다. 본 연구의 목표는 폭포의 성인과 발달과정을 통해 지형적 형상으로 표출되는 유형을 분류하는 것이다. 폭포의 성인과 발달과정은 폭포침식의 특징에 의해 결정되며, 침식에 영향을 주는 요인을 폭포의 높이, 경사도, 구성암석, 하천력으로 간주하고 이들 요인에 따라 폭포의 유형을 구분하고자 하였다. 이 연구를 통해 폭포의 발달과정에 절리시스템이 가장 중요한 요인이며, 절리시스템은 다시 기반암의 특성에 따른 것임을 확인하였다. 유로의 방향과 침식유형은 절리계의 밀도와 방향에 따라 결정되며, 이들이 하상의 경사도와 낙차를 결정한다. 절리계의 유형이 하상경사와 폭포의 낙차 및 경사도 즉 형태를 결정하였다.

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

  • 전계한;최경란
    • 한국과학예술포럼
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    • 제27권
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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.

한국산 양식김의 종류 (SPECIES OF CULTIVATED PORPHYRA IN KOREA)

  • 강제원
    • 한국수산과학회지
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    • 제3권2호
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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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입원환자 낙상 발생 실태와 원인에 관한 분석 연구 (An Analysis of Fall Incidence Rate and Its Related Factors of Fall in Inpatients)

  • 김철규;서문자
    • 한국의료질향상학회지
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    • 제9권2호
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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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Riemann 해법을 이용한 댐 붕괴파의 전파 해석 (Propagation Analysis of Dam Break Wave using Approximate Riemann solver)

  • 김병현;한건연;안기홍
    • 대한토목학회논문집
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    • 제29권5B호
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    • pp.429-439
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    • 2009
  • 댐 붕괴로 인한 극한홍수가 발생하였을 경우, 홍수경보에 대한 대응시간은 일반적인 홍수의 경우보다 훨씬 짧다. 수치모형은 홍수파의 전파양상을 예측하고, 범람지역, 홍수파 도달시간 그리고 침수심 등에 관한 정보를 제공하는데 있어 강력한 도구가 될 수 있다. 그러나 댐 붕괴로 인한 홍수파의 전파는 불연속 흐름이나 마른하도의 전파를 포함하고 있으므로, 수학적으로 표현하기 어려운 경우가 많다. 그럼에도 불구하고 최근에 유한체적기법을 이용하여 댐 붕괴로 인한 홍수범람을 모의하기 위한 수치모형의 개발이 많이 이루어졌다. 유한체적기법은 적분보존형 방정식을 기본으로 하고 있으므로, 불연속 흐름이나 충격파의 해석에 용이하다. 따라서, 본 연구에서는 2차원 보존형 천수방정식의 해석을 위해 유한체적기법과 Riemann 근사해법을 이용한 수치모형을 개발하였다. 그리고 예측단계와 수정단계에서 연속방정식과 운동량 방정식의 보존변수 재구성을 위해 수면경사법과 연계한 MUSCL 기법을 적용하여 시간과 공간에서 2차정확도를 얻었다. 개발한 유한체적모형을 2차원 부분적 댐 붕괴 해석 및 삼각형 융기를 가진 하도에 대한 댐 붕괴 해석에 적용하고, 적용결과를 실험자료 및 기존 연구자의 계산결과와 비교하여 개발모형을 검증하였다.