• Title/Summary/Keyword: 상태유지

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Guidelines and Optimum Treatment for Agriculture Reuse of Reclaimed Water (농업적 용수재이용 수질기준을 고려한 적정 하수재처리에 관한 연구)

  • Jung, Kwang-Wook;Jeon, Ji-Hong;Ham, Jong-Hwa;Yoon, Chun-Gyeong
    • Korean Journal of Ecology and Environment
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    • v.36 no.3 s.104
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    • pp.356-368
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    • 2003
  • Water quality of effluent from wastewater treatment plants (WWTPS) was reviewed to examine the feasibility of agricultural reuse using USEPA and WHO guidelines. It might meet the guidelines for BOD and SS, however, the most critical microbiological concentration was too high and further treatment is required. The pilot study of three treatments were performed to reduce microbiological concentrations. The UV irradiation was proved to be very effective in disinfection of secondary level effluent, and about 30 mW ${\cdot}$ s/$cm^2$ of dose was suggested to meet the even most stringent USEPA guidelines. Slow sand filter demonstrated effective removal of bacteria, and effluent concentration of total coliform (TC), fecal coliform (FC), and E. coli. dropped from about 10,000/100 mL to 300, 200, and 150 MPN/100 mL, respectively, showing over 95% removal. These level of bacterial concentration sufficiently meet the WHO guidelines ($10^3\;{\sim}\;10^5$ FC/100 mL), and could meet the more stringent USEPA guidelines (200 FC/100 mL) if properly applied. Slow sand filter also provided about 50% removal of SS, turbidity, and BOD in addition to bacterial removal. The removal efficiency of pond system was relatively poor, but still showed over 85% removal and effluent concentration of TC, FC, and E. coli was all below 10,000/100 mL. The pond system alone could meet the WHO guidelines, but hardly meet the USEPA guidelines and further treatment might be necessary. Overall, three methods evaluated in the study treat the effluent to meet the WHO microbiological guidelines for agricultural reuse. The UV disinfection and slow sand filter might also could the USEPA guidelines, while the pond system can hardly meet the USEPA guidelines if applied alone. The WHO and USEPA guidelines were made based on data from upland field agricultural system and may not be directly applicable to the paddy field agricultural system. Therefore, national standards for agricultural reuse of reclaimed water should be made considering domestic agricultural systems as well as international guidelines. Also, further investigation is recommended to develop optimum and feasible treatment measures for agricultural reuse of effluent from WWTPs.

Effects of Manually Controlled Ventilation on Gas Exchange during General Anesthesia (용수조절호흡이 폐포환기 정도에 미치는 영향)

  • Suh, Jung-Kook;Suh, Ill-Sook;Kim, Heung-Dae
    • Journal of Yeungnam Medical Science
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    • v.1 no.1
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    • pp.95-100
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    • 1984
  • In the beginning of anesthetic training, one of the clinical practices that anesthetists have to learn is manually controlled ventilatory techniques. The popularity of manually controlled ventilatory techniques has been gradually decreased with increased use for anesthetic ventilators. However it is important and basic for the anesthetists to master manually controlled ventilatory techniques skillfully. Recently, we analyzed the arterial blood gas in 30 cases before and during general anesthesia, and studied the effects of the manually controlled ventilation on the pulmonary gas exchange. The results were as follow; 1) Mean value of $PaCO_2$ during the manually controlled ventilation, $29.9{\pm}2.9mmHg$ was decreased statistically comparing with that of $PaCO_2$ before the anesthesia, $39.8{\pm}2.8mmHg$. 2) Mean values of pH and ${HCO_3}^-$ during the manually controlled ventilation were $7.48{\pm}0.03$, $22.2{\pm}2.4mEq/l$, respectively and values before the anesthesia were $7.41{\pm}0.02$, $25.2{\pm}1.8mEq/l$, respectively. 3) Mean values of $PaO_2$ and $O_2$ saturation during the manually controlled ventilation were $270.0{\pm}28.8mmHg$, $99.6{\pm}0.2%$, respectively and values before the anesthesia were $92.5{\pm}4.0mmHg$, $96.9{\pm}1.0%$ respectively. These results indicates that manually controlled ventilation at our department of anesthesiology produced mild hyperventilatory state. However these were no significant changes in cerebral blood flow and other biochemical parameters.

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Manufacturing process and food safety analysis of sous-vide production for small and medium sized manufacturing companies: Focusing on the Korean HMR market (중소규모 생산업체의 수비드 제품 생산을 위한 공정 및 안전성 분석: 한국 HMR 시장 중심으로)

  • Choi, Eugene;Shin, Weon Sun
    • Korean Journal of Food Science and Technology
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    • v.52 no.1
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    • pp.1-10
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    • 2020
  • The present study identified the restrictions on the use of sous-vide products in the Korean HMR market for small and medium-sized manufacturing companies. A detailed literature review revealed that the HMR market in Korea is close to saturation. Notably, the technologically advanced products produced using sous-vide seem to display significant potential to overcome market saturation. The sous-vide method differs from conventional cooking techniques and is characterized by maintenance of food texture along with flavor enhancement. However, due to the unfamiliarity of the manufacturers with this method and the unclear food safety regulations, mass food manufacturing companies do not agree on using this method; hence, sous-vide production is usually undertaken by small/medium sized companies catering primarily through online marketing portals. This study highlights the various restrictions to the implementation of sous-vide production, and discusses several practical implications of sous-vide production that would help users of this technique enter the HMR market.

Differences of Blood Oxygen Saturation between 20s and 60s due to Amount of Highly Concentrated Oxygen Administration (고농도 산소 공급량에 따른 20대와 60대의 혈중 산소 포화도의 차이)

  • Choi, Mi-Hyun;Kim, Ji-Hye;Lee, Su-Jeong;Yang, Jae-Woong;Yi, Jeong-Han;Jun, Jae-Hoon;Kim, Hyun-Jun;Lee, Tae-Soo;Chung, Soon-Cheol
    • Science of Emotion and Sensibility
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    • v.13 no.1
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    • pp.41-46
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    • 2010
  • The purpose of this study was to examine differences between 20s and 60s in blood oxygen saturation due to 93% oxygen administration of the three levels(1L/min, 3L/min, 5L/min). Ten 20s male($25.0{\pm}1.8$ years), ten 20s female($23.7{\pm}1.9$ years), ten 60s male($68.0{\pm}2.6$ years), and ten 60s female($65.5{\pm}3.1$ years) were selected as the subjects for this study. The oxygen supply equipment(OXUS Co.) provided oxygen by supply rate(i.e., 1L/min, 3L/min, and 5L/min) at a constant rate of 93% oxygen. The experiment consisted of three phases, i.e., Prehyperoxia(5min), Hyperoxia(10min), and Post-hyperoxia(5min). Blood oxygen saturation were measured throughoutthe three phases. By increasing the amount of highly concentrated oxygen administration, blood oxygen saturation was increased. Blood oxygen saturation of 20s was higher than 60s. Blood oxygen saturation was greater during Hyperoxia than during Pre- and Post-hyperoxia. However, rising rate of blood oxygen saturation of 60s by oxygen administration was higher than 20s.

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Engineering Characteristics of Wet-mixing Solidified Soil in Pavement Surfacing (습식 경화교반토 포장의 공학적 특성)

  • Yoo, Ji-Hyeung;Shu, Dong-Hyuk;Lee, Seong-Won
    • International Journal of Highway Engineering
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    • v.6 no.3 s.21
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    • pp.1-7
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    • 2004
  • Roads, like bikeways, parkways and walks, are to be just capable of supporting light traffic and traveling public, but they are required to be human friendly and environmental-oriented. Lately soil-solidifier mixture, a kind of soil-cement, has developed and has been applied to the recycling and environment-oriented pavement as the surfacing material. Soil-solidifier pavement structure has been designed by only experience. To design this pavement mechanically, it is necessary to find out basic engineering properties of soil-solidifier mixture. This study focuses on finding out mechanical characteristics of the mixture according to mixture proportions and aging. Test molds with various mixture proportions are made, and then unconfined strength tests are performed for test molds with aging of the mixture. As the result of this study, it is found that the strength of the mixture increases with amount of cement and that maximum strength is achieved at 6%$\sim$8% of the ratio of solidifier and water. The strength increase rapidly until 14 days, after then slowly. After 28 days the strength of the mixture approaches to the constant value. The heat of hydration during curing of the mixture is measured no significantly. It also shows that temperature characteristics of the mixture is similar to that of soil. Since this mixture is mixed with soil and is able to improve engineering problems in pavement due to temperature, this mixture is expected to use effectively in the environment-oriented pavement for light traffic.

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Development of Neural Network Based Cycle Length Design Model Minimizing Delay for Traffic Responsive Control (실시간 신호제어를 위한 신경망 적용 지체최소화 주기길이 설계모형 개발)

  • Lee, Jung-Youn;Kim, Jin-Tae;Chang, Myung-Soon
    • Journal of Korean Society of Transportation
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    • v.22 no.3 s.74
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    • pp.145-157
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    • 2004
  • The cycle length design model of the Korean traffic responsive signal control systems is devised to vary a cycle length as a response to changes in traffic demand in real time by utilizing parameters specified by a system operator and such field information as degrees of saturation of through phases. Since no explicit guideline is provided to a system operator, the system tends to include ambiguity in terms of the system optimization. In addition, the cycle lengths produced by the existing model have yet been verified if they are comparable to the ones minimizing delay. This paper presents the studies conducted (1) to find shortcomings embedded in the existing model by comparing the cycle lengths produced by the model against the ones minimizing delay and (2) to propose a new direction to design a cycle length minimizing delay and excluding such operator oriented parameters. It was found from the study that the cycle lengths from the existing model fail to minimize delay and promote intersection operational conditions to be unsatisfied when traffic volume is low, due to the feature of the changed target operational volume-to-capacity ratio embedded in the model. The 64 different neural network based cycle length design models were developed based on simulation data surrogating field data. The CORSIM optimal cycle lengths minimizing delay were found through the COST software developed for the study. COST searches for the CORSIM optimal cycle length minimizing delay with a heuristic searching method, a hybrid genetic algorithm. Among 64 models, the best one producing cycle lengths close enough to the optimal was selected through statistical tests. It was found from the verification test that the best model designs a cycle length as similar pattern to the ones minimizing delay. The cycle lengths from the proposed model are comparable to the ones from TRANSYT-7F.

Minimization of Small Bowel Volume within Treatment Fields Using Customized Small Bowel Displacement System(SBDS) (골반부 방사선 조사야 내의 소장 용적을 줄이기 위한 Small Bowel Displacement System(SBDS)의 사용)

  • Lim Do Hoon;Huh Seung Jae;Ahn Yong Chan;Kim Dae Yong;Wu Hong Gyun;Kim Moon Kyung;Choi Dong Rak;Shin Kyung Hwan
    • Radiation Oncology Journal
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    • v.15 no.3
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    • pp.263-268
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    • 1997
  • Purpose : Authors designed a customized Small Bowel Displacement System (SBDS) to displace the small bowel from the Pelvic radiation fields and minimize treatment-related bowel morbidities. Materials and Methods : From August 1995 to Mar 1996. 55 consecutive patients who received pelvic radiation therapy with the SBDS were included in this study. The SBDS consists of a customized styrofoam compression device which can displace the small bowel from the radiation fields and an individualized immobilization abdominal board for easy daily setup in prone position After opacifying the small bowel with Barium3, the patients were laid Prone and posterior-anterior (PA) and lateral (LAT) simulation films were taken with and without the SBDS. The areas of the small bowel included in the radiation fields with and without the SBDS were compared. Results : Using the SBDS, the mean small bowel area was reduced by $59\%;on\;PA\;and\;51\%$ on LAT films (P=0.0001). In six Patients (6/55. $11\%$), it was Possible that no small bowel was included within the treatment fields. The mean upward displacement of the most caudal small bowel was 4.8 cm using the SBDS. Only $15\%$ (8/55) of patients treated with the SBDS manifested diarrhea requiring medication. Conclusion : The SBDS is a novel method that can be used to displace the small bowel away from the treatment portal effectively and reduce the radiation therapy morbidities. Compliance with setup is excellent when the SBDS is used.

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In Situ Surfactant Flushing of Contaminated Site (계면 활성제를 이용한 In Situ 토양 세척)

  • 염익태;안규홍
    • Journal of Korea Soil Environment Society
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    • v.2 no.2
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    • pp.9-24
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    • 1997
  • Surfactant-aided in situ soil flushing has been proposed as an alternative for the expensive and time consuming 'pump and treat' technology in remediation of contaminated soil and groundwater Injected surfactants can effectively solubilize contaminants sorbed to the soil matrix or nonaqueous phase liquids(NAPLs) in residual saturation. The contaminants solubilized in groundwater are recovered and treated further. The theoretical background of the technology and the results of the field operations, mostly in the US. were summarized. In addition, the factors crucial to the successful application of the technology were discussed. Cost analyses and technical limitations in current applications were also discussed. In conclusion, it is likely that in situ surfactant flushing become a viable option for soil remediation in limited cases. Currently, further advances with respect to operation cost and to treatment efficiency are required for more extensive application of the technology. However, the current trends in soil remediation, specially the growing emphasis on risk based corrective action and natural attenuation, will increase the competitiveness of the technology. For example, removal of easily washable contaminants by short term soil flushing followed by long term monitoring and natural attenuation can greatly reduce the operation cost and time.

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The Relationship Between Health Behavior and Family Environment in Middle School Students (중학생(中學生)의 건강행위(健康行爲)와 가족환경(家族環境)과의 관계(關係))

  • Kim, Eun Hee;Park, Jae Yong;Cha, Byung Jun;Kam, Sin
    • Journal of the Korean Society of School Health
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    • v.10 no.1
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    • pp.87-97
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    • 1997
  • The purpose of this study is to examine the importance of family environment for middle school student's health behavior. In order to do this we collected data through the questioning of 543 male students and 512 female students in 4 Pusan middle schools. The results of this study are summarized as follows. The score on their family cohesion and adaptability was 57.8, 43.5 on the average for male students and 59.8, 44.8 in female students. The score on their family adaptability and cohesion was higher in fema1e students than male students. The score of their Breslow health behavior was 4.20 from a total of 7.00, the total score of health behavior was 131.4 from a total of 176.0 scores. The students had a 43.9 out of 60.0 in personal hygiene and daily habits, 32.8 out of 40.0 for infectious disease preventive behavior, 30.2 out of 40.0 in accident prevention, 24.5 out of 36.0 in mental health. In the cases of males, the score for Breslow health behavior was higher the lower the school grade, the younger the parents, the higher the educational level of parents, the more comfortable the family, and the higher the economic state. There was a statistically significant difference with regard to family cohesion and adaptability. In the cases of females, The total score for health behavior was higher. However, the difference was not significant in other fields. With the multiple regression analysis, the health behavior of middle school student was associated significantly with sex (female students), grade, family cohesion, and adaptability. In Breslow health behavior, scale sex (male students), father's age, family cohesion and the harmony of parents were significant variables. From the results of this study, a good family environment fur middle school students is very important.

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Studies on the Effect of Cation on the Activity at the 5th Instar Larvae of Bombyx mori (5령유충의 배맥관운동에 대한 양이온의 영향에 관한 연구)

  • 윤종관;사기언
    • Journal of Sericultural and Entomological Science
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    • v.18 no.2
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    • pp.89-93
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    • 1976
  • The physiological saline solution for animals is known as Ringer's solution which is used for keeping the function of cold blooded vertebrate animals. Primaily the saline solution is used for the purpose of perfusion experiment in frogs. Later the saline solution is applied in several kinds of animals including human being with satisfactory results. However, this saline solution was introduced to silkworm and it was found that the result was not as successful as in the case of other animals and human being. Normally, in the case of silkworm, the physiological saline solution is prepared in order to maintain the normal function of separated organs and tissues. To this end, the saline solution is adjusted to contain the certain amount and strength of ions, osmosis pressure and hydrogen concentration. The most of cases, the physiological saline solution should be prepared so that the constituent of the solution be the same with the blood selium and body fluid. The hydrogen concentration in the ion element of the saline solution is adjustable by adding Na$\^$+/, K$\^$+/, Ca$\^$++/, Mg$\^$++/ which are followed by adding of buffer solution such as NaHCO$_3$and NaH$_2$PO$_4$. Determination of optimum concentration of cation in the physiological saline solution, and the optimum mixing rate of more than two kinds of cations are based on the movement of dorsal vessel in the silkworm larvae. The optimum concentration of cations in the solution is prepared by adding NaCl solution which is under zero point. However, this solution was further added with the different concentration of KCl and CaCl$_2$. By dropping the prepared solution on the 5th larvae, the effects of solution was measured. The measurement was done by observation of movement' of dorsal vessel and its time length, and the number of pulses. According to the experiment, it was found that when only NaCl solution was applied, the number of pulses is increased for a moment, and the pulse stopped after one hour or so. When KCl solution was added the time of pulse was prolonged and in the contrast, the number of pulses was slow down. If KCl and CaCl$_2$solutions are added the time of pulse was further prolonged. Even though the adding of KCl and CaCl$_2$are found to be effectible, the correlation between the concentration of solution and the movement of dorsal vessel was not observed. However, it was same in the case of adding Ca$\^$++/ or K$\^$+/. It was found that when Mg$\^$++/ was added to dorsal vessel the number of the pulses was not decreased although the prolonged time pulse was observed.

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