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Transportation Modeling of Conservative Pollutant in a River with Weirs - The Nakdong River Case (수중보를 고려한 하천에서 보존성 오염물질의 이송특성 분석 - 낙동강을 중심으로)

  • Lee, Jungwoo;Bae, Sunim;Lee, Dong-Ryul;Seo, Dongil
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.12
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    • pp.821-827
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    • 2014
  • The 4major river project has caused changes in flow and water quality patterns in major rivers in Korea including the Nakdong River where several toxicant release accidents have had occurred. Three dimensional hydrodynamic model, the Environmental Fluid Dynamics Code (EFDC), was applied to evaluate the effect of geomorphological change of the river on the advection and dispersion patterns of a conservative toxic pollutant. A hypothetical scenario was developed using historical data by assuming a toxic release from an upstream location. If there is a toxic release at the Gumi Industrial Complex, the toxic material would be detected after 2.22 and 9.83 days at Chilgok and Gangjung weir, respectively, in the new river system. It was estimated that they took at least 12 times longer than those with the river conditions before the project. Effect of relocation of intake towers for Daegu Metro City to upstream of Gumi City was also evaluated using the developed modeling system. It was observed that hydraulic residence time would be increased due to decreased flow rate and thus due to lowered water level. However, peak concentration differences were found to be about 2% lower in both places due to increased dispersion effect after the relocation.

A Study on Children's Park Facility Planning Scheme according to User Behavior and Characteristics (이용자 행태 및 특성에 따른 어린이공원 시설 계획 방안에 관한 연구)

  • Lee, Dong Hun;Lee, Seok Hwan;Baek, Ki young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.12
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    • pp.232-241
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    • 2016
  • Among city parks, children's parks are more accessible than other parks in the city, and there are many users. They are used not only for children's playgrounds, but also for relaxation and leisure spaces for local residents. On the other hand, as a result of focusing on the quantitative increase by the engineering division by the Urban park Act, the consideration of the users of various classes is insufficient. The purpose of this study was to analyze the actual use of children parks in single - family housing and communal housing areas, and to identify the problems and future directions of the use of children parks. For this purpose, a case study and a document survey were conducted. First, through scholarship research, the theoretical review and the present situation were summarized based on the data, such as the papers and research reports related to the existing children's park. The status of the location, facilities and management were then identified through interviews and site visits with the children's park management staff. As a result, the children's park was utilized as a leisure space with high accessibility in the living area. As a result, the residence time of most users was within 1 hour to 2 hours. In particular, use by elderly people was higher than the use by children. Therefore, it would be desirable to design the future planning of the children's parks and to plan the arrangement in accordance with the future - oriented multi - purpose neighborhood type children's park.

Study on The Thermochemical Degradation Features of Empty Fruit Bunch on The Function of Pyrolysis Temperature (반응온도에 따른 팜 부산물(empty fruit bunch)의 열화학적 분해 특성에 관한 연구)

  • Lee, Jae Hoon;Moon, Jae Gwan;Choi, In-Gyu;Choi, Joon Weon
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.3
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    • pp.350-359
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    • 2016
  • We performed fast pyrolysis of empty fruit bunch (EFB) in the range of temperature from $400{\sim}550^{\circ}C$ and 1.3 s of residence time. The effect of temperature on the yields and physicochemical properties of pyrolytic products were also studied. Elemental and component analysis of EFB showed that the large amount of potassium (ca. 8400 ppm) presents in the feedstock. Thermogravimetric analysis suggested that the potassium in the feedstock catalyzed degradation of cellulose. The yield of bio-oil increased with increasing temperature in the range of temperature from $400{\sim}500^{\circ}C$, while that of gas and biochar decreased and showed monotonous change each with increasing temperature. When the EFB was pyrolyzed at $550^{\circ}C$, the yield of bio-oil and char decreased while that of gas increased. Water content of the bio-oils obtained at different temperatures was 20~30% and their total acid number were less than 100 mg KOH/g oil. Viscosity of the bio-oils was 11 cSt (centistoke), and heating value varied from 15 to 17 MJ/kg. Using GC/MS analysis, 27 chemical compounds which were classified into two groups (cellulose-derived and lignin-derived) were identified. Remarkably the concentration of phenol was approximately 25% based on entire chemical compounds.

Environment isotope aided studies on river water and ground water interaction in the Han River basin (동위원소를 이용한 한강유역의 지하수와 지표수의 연관성에 관한 연구)

  • 안종성;김재성
    • Water for future
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    • v.16 no.4
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    • pp.245-252
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    • 1983
  • Recently river water pollution in Korea is given rise to serious problem in aspect of crop production, drinking well, water contamination and etc. Under these urgent situations, it is prime importance to protect water resources from pollutants. An environmental isotope survey of the groundwater form the shallow alluvial and the underlying crystalline rock aquifer of the Han River Basin has been undertaken, Analysis of the data has I) confirmed the hypothesis that the groundwater from the metropolitan area is recharged from the river whereas that form the non-urbanized region of the Basin is replenished by the infiltrating precipitation; ii) shown that crystalline rock aquifers are recharged by the ground water form the overlying alluvium. Old groundwater is a group of wells with tritium values in the range of 0 to 2 TU. These low values indicate that the water sampled was recharged much ealier, at least a few decades, than the other groundwater samples of higher tritium content. The low values in this region may, in fact, reflect the effect of the impermeable clay layers which impede infilteration from the surface. Stable isotope evidence confirmed that a recharge in the karst area occurs at a significantly greater elevation than that to the alluvial aquifer. An analysis of the tritium level collected over an annual cycle suggests that the residence time of groundwater is probably not more than a few months. There does not appear to be any correlation between the trace level of Zn, Mn and Pb in the groundwater and the mechanism of the recharge.

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The Estimation of Water Quality Changes in the Keum River Estuary by the Dyke Gate Operation Using Long-Term Data (장기관측자료에 의한 금강하구둑 수문조작에 따른 수질 변화 평가)

  • KWON Jung-No;KIM Jong-Gu;KO Tae-Seung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.4
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    • pp.348-354
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    • 2001
  • This study was conducted to estimation of change characteristics for water quality by the dyke gate operation in the Keum River estuary. The estimation data made use of surveyed data in Keum River estuary by NERDI (National Fisheries Research and Development Institute) during $1990\~1999$. Shown to compare water quality changes at st. A and st. D in Figure 1, the concentrations of TSS, COD and nutrients at st. A were as high as about $2\~4$ times than those at st. D due to affection of fresh water discharge in the Keum River. The percentages of water quality change at surface water by dyke gate operation in the Keum River estuary were shown that TSS (Total Suspended Solid) was decrease to $56\%,\;47\%$ at st. A and D, and COD (Chemical Oxygen Demand) was increase to $68\%,\;71\%$ at st. A and D, respectively. The changes percentage of DIN (Dissolved Inorganic Nitrogen) by dyke gate operation in the Keum River estuary were increase high to $95\%$ at surface water and $7\sim30\%$ at bottom water, but those of DIP (Dissolved Inorganic Phosphorus) were increase to $2.8\sim8.6\%$ at surface water and $28\%$ at bottom water. The range of fluctuation for water quality at each station by dyke gate operation has shown that salinity and TSS are little better than before dyke gate operation, but COD show highly fluctuation. Also we studied estimation of characteristics of water quality change by the season, COD was increased except the summer, TSS was decreased to all season. DIN was increased to about $61\sim172.1\%$ for all season, but DIP was increased to the spring and decreased to the autumn, DIN enrichment in the estuary by dyke gate operation are interpreted to improvement of organic matter decomposition and nitrification by increasing the residence time and to increase nutrient flux in sediments due to decreasing dissolved oxygen and increasing a deposit matter.

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A Study of the Nursing Needs of Hospitalized medical Patients by Means of Nursing History Form (간호력(Nursing History)을 통해 본 내과 입원환자의 간호요구)

  • 전경애
    • Journal of Korean Academy of Nursing
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    • v.7 no.2
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    • pp.1-10
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    • 1977
  • Personalized Patient centered nursing care is increasingly difficult to achieve despite the fact that it remains one of our consistent goals. So, we must find away to individualized nursing care. One means, to achieve this is by use of the nursing history form, which has been developed to help the nurse make maximum use of her limited time with the patient, by obtaining systematically the information needed to plan his nursing care. The nursing history form can be used to collect data about individual nursing needs but also it lends itself to the collection of epidemiological data relevant to the needs of patient population. So this study was undertaken in an attempt to describe the general characteristics of the population studied, to find out their perceptions and expectations related to their illness and hospitalization, to find out specific basic needs and to examine the relationship between the patients nursing needs and demographic characteristics through the responses to the nursing history questions. The study population defined and selected was all the patients (70) who were admitted to Yonsei University Hospital from October 1 - 15, 1975. The direct interview method was used and the data were categorized by the investigator, according to the nature of responses to each question and were subjected to the percentile and the chi- square tests. The findings can be summarized as follows 11. General characteristics of the study population ; The population was made up mainly of urban patients who were highly educated. The age was equally distributed. 2. Patients, perceptions and expectations related to illness and hospitalization ; 88.6% of the patients knew about the reason for hospitalization but 64. 5% could state symptoms only. 37.5% recognized the cause of illness. Approximately three fourth of the patients expressed on expectation for early recovery. 60.0% of the patient responses indicated, that they expected less than 10 days of hospitalization. Of the total responses regarding hospitalization, 45.7% were negative about the post -hospitalization expectation, 45.7% expected to return to work. As a result of these findings, we can see that there is a great educational need, a psychological need and environmental need for adaptation to the hospital and a socio- economic need for the post - hospitalization period. 3. Specific basic needs : The physical needs include the problem of getting sufficient sleep (50.0%), difficulty in food intake(47.1%), problems with hospital diet (47.0%), abnormal condition of the skin(44.3%), problems with bowel elimination(35.7%), assistance with bathing(35.7%), pain(30.0%), difficulty in walking(30.0%) , difficulty in seeing(30.0%) problems in urinary elimination(20.0%) , and difficulty in hearing(10.0%), 4. Nursing needs and epidemiological characteristics ; Age distribution was related to the rendition of the mouth but no significant differences were observed statistically with the patients responses to the other nursing history questions according to the epidemiological variables of age, sex, education and residence.

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Effects of Steam and Temperature on CO2 Capture Using A Dry Regenerable Sorbent in a Bubbling Fluidized Bed (기포 유동층 반응기에서 건식 재생 흡수제를 이용한 이산화탄소 회수에 미치는 스팀 및 온도의 영향)

  • Seo, Yongwon;Moon, Young Sub;Jo, Sung-Ho;Ryu, Chong Kul;Yi, Chang-Keun
    • Korean Chemical Engineering Research
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    • v.43 no.4
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    • pp.537-541
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    • 2005
  • A bubbling fluidized bed reactor was used to study $CO_2$ capture from flue gas using a sodium-based dry regenerable sorbent, sorbA which was manufactured by Korea Electric Power Research Institute. A dry sorbent, sorbA, consists of $Na_2CO_3$ for absorption and supporters for mechanical strength. $CO_2$ capture was effective in the lower temperature range of $50-70^{\circ}C$, while regeneration occurred in the range of $120-300^{\circ}C$. To increase initial $CO_2$ removal, some amount of steam was absorbed in the sorbents before injecting simulated flue gas. It was possible to remove most $CO_2$ for 1-2 minutes at $50^{\circ}C$ and residence time of 2 seconds with steam pretreatment. Little or no reduction in initial reaction rate and capture capacity was observed in multicycle tests. The carbonated and regenerated sorbent samples were analyzed by NMR to confirm the extent of reaction. The results obtained in this study can be used as basic data for the scale-up design and operation of the $CO_2$ capture process with two fluidized bed reactors.

Preparation of MFI Zeolite Catalyst Supported on Silicalite Foam and Its Catalytic Property in the Cracking of n-Octane (실리카라이트 폼에 담지된 MFI 제올라이트 촉매의 제조와 n-옥탄 분해반응에서 이들의 촉매 성질)

  • Jung, Je Sik;Choi, Dong Bae;Song, Kyeong Keun;Ha, Kwang;Song, Yo Soon;Seo, Gon
    • Korean Chemical Engineering Research
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    • v.43 no.4
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    • pp.452-457
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    • 2005
  • Foam-type MFI zeolite catalyst was prepared by dispersing fine ($-0.2{\mu}m$) particles of MFI zeolite on silicalite foam. Catalytic cracking of n-octane was investigated over the foam-type catalyst and Delplot method was employed to interpret product compositions for deducing reaction mechanism. The Si/Al molar ratio of dispersed MFI zeolite was estimated 25 and its dispersed amount of silicalite foam was 25 wt%. Since the apparent density of the foam type catalyst was very low $0.11g{\cdot}cm^{-3}$, the catalyst loading amount could be varied from 0.02 g to 0.5 g without concerning pressure drop, providing a wide variance in the residence time of the reactants and products. The conversion and olefin yield in the catalytic cracking of n-octane increased with the catalyst loading. The product composition was very simple and could be explained by applying the protolytic cracking mechanism when the catalyst loading was small. Higher loading of the catalyst brought about further reactions of cracked products, accumulating lower olefin and paraffin with low reactivity in product stream and resulting in complex product composition.

A Study on the Application of the Korean Valuation Weights for EuroQoL-5 Dimension (EuroQoL-5 Dimension 한국 가중치 모형의 적용 연구)

  • Lee, Young-Hoon;Choi, Jin-Su;Rhee, Jung-Ae;Ryu, So-Yeon;Shin, Min-Ho;Kim, Jin-Hee
    • Korean Journal of Health Education and Promotion
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    • v.26 no.1
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    • pp.1-13
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    • 2009
  • Objectives: This study was conducted to estimate the health-related quality of life (HRQOL) using EuroQoL-5 Dimension (EQ-5D) and to identify its related factors among urban-dwelling adults. Methods: The data for this study were obtained from 1,134 subjects aged $20\sim91$, who participated in 'Survey on the health status and demand for health' in two cities of Korea (Dong-gu, Gwangju and Suncheon-si, Jeollanamdo). The HRQOL was measured using the EQ-5D instrument and EQ-5D index scores were calculated by two Korean valuation study model using time trade-off method. Results: The mean EQ-5D index scores for all subjects were $0.865{\pm}0.218$ (model A), and $0.921{\pm}0.170$ (model B). The EQ-5D index score was significantly different according to demographic and socioeconomic characteristics (gender, age, marital status, education, occupation, income, and health security system), self-rated health condition, health-related psychological assessments (enough sleep, fatigue rate, stress rate, and degree of satisfaction on the residence). The results of multiple linear regression showed that age, marital status, income, coverage of medical insurance, self-rated health condition, and fatigue rate were significantly related common statistical factors of HRQOL in two Korean valuation study model. Conclusion: Among the adults residing in urban environment, the HRQOL was significantly lower on the subjects with following conditions: higher age, being alone without a spouse as a result of death, divorce or separation, low income, medical aid program, poor self-rated health condition, and chronic fatigue. In order to improve the urban adults' quality of life, healthcare policy and health promotion program must be developed with considerations to factors related to the HRQOL.

A Clinical study on Pediatric Bronchial Asthma (소아천식에 대한 임상적 고찰)

  • Kim, Yun-Hee
    • The Journal of Pediatrics of Korean Medicine
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    • v.16 no.1
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    • pp.133-148
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    • 2002
  • Objective : This study was to investigate more effective oriental medical treatment for Pediatric Bronchial Asthma Method : Aroma therapy and Herbal medicine was given to 28 pediatric bronchial asthma patients(19 males and 9 females) for about 5months from the First, August 1999 The Fifth, January 2002. Results: 1. Demographic factor : The sample consisted of 28 persons among whom 19 were male, 9 were female. The age ranges from 1 year old to 6 year old. Less than 2 year old were 4 and 2-6 year old were 20. 2.Residence : Apartment and villar dwellers were 19(67.9%), Residential street divellers were 9(32.1%). 3.Age distribution at on set : 6(21.4%) fell ill befor 1 year old and 22(78.6%) fell ill after 1 year old 4. The period of illness : 9(32.2%) suffered during 1-3 year and 6(21.4%) suffered during 6 mouth-1year and 6(21.4%) suffered during more than 3 year. 5. Frequency of the symptoms : The symptoms appeared 2-3 times a year in the case of 16(57.2%), one time a year in the case of 1, 4 times a year in the case of 6(21.4%). 6. Concomitance symptoms : All experienced coughing sign, wheezing, 23(82.1%) experienced epistaxis, nose dripping, 13(46.4%) got fever, anorexia. 7. Past history of illness : 16(57.1%) got brochiolitis, brochitis, 12(42.9%) suffered pneumonia, 9(32.1%) had allergic rhinitis. 2 had allergic rhinitis, sinusitis, atopic dermatitis, bronchial asthma, 3 got atopic dermatitis, bronchial asthma and 7 had allergic rhinitis, sinusitis, bronchial asthma, 8. Family disease : In the case of family disease, 21(75%) had allergic dermatitis, 9(42.9%) had bronchial asthma, 8(38.1%) had allergic dermatitis. 9. The symptoms became very severe in the change of season in the case of 13(46.4%) and in the case of 11(39.3%), the change of season made no difference 10. Associated caused of induction symtoms : 28(100%) got sick by common cold, infectional disease, 8(28.6%) got sick by cold food, cold air 11.The kind of therapy : 15(53.6%) got oriental therapy after occidental therapy, 11(39.3%) took only oriental therapy. 12. Improvement degree of each symptoms : In the case of cough and wheeze that are the main symptoms of bronchial asthma, 78.6% and 64.3% of the patients replied < improvement > and in the case of dyspnea, tachypnea 41.7% of the patients replied . In other symptoms, all replied 13. Degree of satisfaction : 19(67.9%) replied , 2(7.1%) replied . Conclusion : Herbal medicine and aroma therapy proved to be a very effective oriental medical treatment for pediatric bronchial asthma.

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