• 제목/요약/키워드: average discharge

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A Study on Process Optimization for CSOs Application of Horizontal Flow Filtration Technology (수평흐름식 여과기술의 CSOs 적용을 위한 공정 최적화 연구)

  • Kim, Jae-Hak;Yang, Jeong-Ha;Lee, Young-Shin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제19권2호
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    • pp.56-63
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    • 2018
  • The management of Combined Sewer Overflows(CSOs) and Separated Sewer Overflows(SSOs) discharge directly to the effluent system in an untreated state, which occurs when the facility capacity is exceeded due to heavy rain, has become an important issue in recent years as the heavy rain becomes a regular phenomenon. Despite the continuous development of filtration technology, targeting densely populated urban areas, CSOs are rarely applied. Therefore, this study was carried out to optimize the process to apply CSOs in a pilot-scale horizontal flow filtration system with a rope-type synthetic fiber. The research was carried out in two steps: a preliminary study using artificial samples and a field study using sewage. In the preliminary study using an artificial sample, head loss of the filter media itself was analyzed to be approximately 1.1cm, and the head loss was increased by approximately 0.1cm as the linear velocity was increased by 10m/hr. In addition, the SS removal efficiency was stable at 81.4%, the filtration duration was maintained for more than 6 hours, and the average recovery rate of 98% was obtained by air backwashing only. In the on-site evaluation using sewage, the filtration duration was approximately 2 hours and the average removal efficiency of 83.9% was obtained when belt screen (over 450 mesh) was applied as a pre-treatment process to prevent the premature clogging of filter media. To apply the filtration process to CSOs and SSOs, it was concluded that the combination with the pre-treatment process was important to reinforce the hydraulic dimension for the stable maintain of operation period, rather than efficiency. Compared to the dry season, the quality of incoming sewage was lower in the rainy season, which was attributed to the characteristics of the drainage area with higher sanitary sewerage. In addition, the difference in removal efficiency according to the influent quality of the wet season and dry season was small.

Studies on Spat Production of the Sun and Moon Scallop, Amusium japonicum japonicum (GMELIN) (해가라비, Amusium japonicum japonicum (GMELIN) 종묘생산에 관한 연구)

  • Son, Pal-won;Ha, Dong-soo;Rho, Sum;Chang, Dae-soo;Lee, Chang-hoon;Kim, Dae-Kweon
    • Journal of Aquaculture
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    • 제11권3호
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    • pp.371-380
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    • 1998
  • This study has been conducted to develop the techniques for spat production of the sun and moon scallop from January 1995 to December 1996. With the adult scallops collected from the Sogwipo area, spawning induction and larvae rearing were attempted several times and monthly changes of GSI were also monitored during the experimental period. The results obtained wre as follows. 1. GSI started to increase from June and showed the maximum value of 22.17 and 14.98 in female and male respectively in November, and then gradually decreased from December. 2. Spawning induction by heating method turned out to the most efficient way showing the responding rate of 64.8~91.5%. The responding temperature was $21.4~26.4{\circ}C$ which was $3.1~8.5{\circ}C$ increased from the rearing temperature of $16.3~18.3{\circ}C$. An average number of eggs spawned was $9.2{\times}10^5$ 3. the average size of eggs after fertilization was about $72{\mu}m$ in diameter. The first polar body discharge, blastula formation, and trochopore larvae appearance occurred 30 mininutes, 18 hours, and 22 hours after fertilization respectively. 4. Settling rates in various collectors were similar one another, whereas pouring larvae in the mesh was the most efficient way for larval setting. 5. The spates grew to be 1mm in their shell length for the first 50 days after fertilization and 9.6mm in 135days. 6. Correlation between shell length (SL) of the spat and the number of days (X) after spat settlement could be expressed as $SL=257.75e ^{0.0272x}$(r=0.9100).

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Correlations between the Stream Morphological Characteristics and the Hydraulic Geometry Characteristics for the Basin (유역(流域)의 하천형태학적(河川形態學的) 특성(特性)과 수리기하학적(水理幾何學的) 특성(特性)과의 상관성(相關性))

  • Ahn, Sang Jin;Yoon, Yong Nam;Kang, Kwan Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • 제2권1호
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    • pp.1-17
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    • 1982
  • The stream morphological characteristics of a river basin has a close correlation with the hydrological and hydraulic characteristics of the basin. In this study the correlations of flow duration and Hydraulic geometry with the stream morphological characteristics as well as the correlation between flow duration and hydraulic geometry were analyzed bases on the data for the Geum River basin. The purpose of this study was to provide the necessary informations for water utilization projects at ungauged locations along the river course. First of all, the stream morphological characteristics was analyzed based on the Horton's three laws on the morphology of a stream that is, the law of stream number, the law of average stream length and the law of average stream slope. As is the case for majority of the rivers it was found that the Geum River basin was well developed according to the Horton's laws. High correlations were also found between the basin characteristics and the channel characteristics. The flow duration curves obtained with the daily stream flow data of 10~90% frequency of occurences at the five stage gauging stations in the Geum River could, in general, be expressed as an exponential functional relationship. The concept of proportional stream ordering system was employed to describe continuously the longitudinal variation of the stream morphological characteristics, and the mathematical model was formulated for the discharge-frequency-proportional stream order relationship. With the morphological characteristics as a common parameter the relationships with flow duration, drainage area were established in mathematical expressions, respectively.

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Results of Arthroscopic-assisted Minimally Invasive Removal of a Lateral Periarticular Plate used for the Treatment of AO Type-C Distal Femoral Fractures (AO C-형 원위 대퇴골 골절의 치료로 삽입된 관외측 금속판의 절경 보조하 최소 침습적 제거의 결과)

  • Kim, Young-Mo;Lee, June-Kyu;Yang, Jae-Hoon;Kim, Bo-Kun;Lee, Won-Gu
    • Journal of the Korean Arthroscopy Society
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    • 제13권1호
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    • pp.46-52
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    • 2009
  • Purpose: To evaluate the usefulness of minimally invasive arthroscopy-assisted plate removal of a laterally inserted periarticular distal femur plate used for the treatment of AO type-C distal femur fractures. Materials and Methods: From October 2002 to November 2005, we evaluated 17 patients whose plates were removed through minimally invasive arthroscopy-assisted plate-removal technique and 15 patients who got their plates removed through conventional method without using arthroscopy, 32 patients in total. All these patients included in this study initially underwent open reduction and internal fixation of the distal femoral fractures with a lateral plate, and complained of continued pain over the lateral femoral condyle after the fracture fixation. The average age was 42.6 (ranges: 20~66) and initial fracture types included 16 cases of C1, 11 cases of C2, and 5 cases of C3 following AO/ASIF classification guidelines. Measured outcomes included: associated intra-articular pathologies, time needed to return to activities of daily living, patients' overall satisfaction, complications following the removal of hardware, and pain before and 6 months after the operation. Results: The distal-most end of the plate was placed in the knee joint in all cases and damage of the lateral articular capsule was found in 23 cases. Continuous wound discharge after surgery was found in one case who underwent arthroscopy-assisted plate removal, and it was treated by irrigation and re-suture. Average time needed to return to activities of daily living was 7 days in arthroscopy assisted group and 7.6 days in conventionally removed group. Fourteen patients (82.4%) who underwent arthroscopyassisted plate-removal reported above 'fair' satisfaction and the Visual analog scale pain score decreased from 4.9 to 1.9, six months after the plate removal. Thirteen patients(86.7%) who underwent conventional plate removal reported above 'fair' satisfaction and the Visual analog scale pain score decreased from 5.2 to 2.5, six months after the operation. Conclusion: Through minimally invasive arthroscopic-assisted plate removal, intrarticular pathology of the knee joint was able to be simultaneously identified and treated at the time of hardware removal. Damage of lateral capsule of the knee joint caused by the inserted plate for the treatment of type C distal femoral fracture was very frequently found and following the plate removal, patients experienced an improvement in pain score. We therefore recommend routine lateral distal femoral plate removal if the bony union is attained in such cases as type C distal femoral fractures whose distal most end of the plates are located in the joint.

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Monitoring of Seasonal Water Quality Variations and Environmental Contamination in the Sambo Mine Creek, Korea (삼보광산 하류 수계의 계절별 수질변화와 오염도 평가)

  • Jung, Goo-Bok;Lee, Jong-Sik;Kim, Won-Il;Ryu, Jong-Su;Yun, Sun-Gang
    • Korean Journal of Environmental Agriculture
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    • 제27권4호
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    • pp.328-336
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    • 2008
  • Metal mining district drainage is a well recognized source of environmental contamination. Oxidation of metal sulfides produces acidic and metal-rich waters that contaminate local surface water and ground water in mines, mine dumps, and tailing impoundments. This monitoring study was carried out to investigate the stream water quality and pollution as affected by the Sambo mine drainage in relation to the relative distance from the mine. It obvious that pH values of the mine drainage ranged from 5.8 to 6.9, while the average concentrations of the dissolved chemical constituents for EC, $SO_4^{2-}$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were $1.77\;dS\;m^{-1}$, 929, 14.6, 263.3, and 46.9 mg/L in mine drainage discharged from the main waste rock dumps (WRD), respectively. Furthermore, EC values and sulfate concentrations exceeded the critical toxicity levels in agricultural water for rice plant ($1.0\;dS\;m^{-1}$ for EC and 54.0 mg/L for $SO_4^{2-}$). Also, the average of dissolved cadmium concentrations ($0.016{\sim}0.021\;mg/L$) was higher than water quality standard (0.01 mg/L) for agricultural water in Korea, in addition to Zn, Fe and Mn were higher than trace metals maximum concentrations which recommended by FAO for irrigation water. The results indicate that mine drainage discharged from the Sambo mine affected stream water at least to distance of 1 km downstream of the mine water discharge point. EC values, $SO_4^{2-}$ and $Ca^{2+}$ concentrations in discharged water positively correlated with dissolved Cd, Zn, Al and Mn concentrations, while the pH values negatively correlated. In addition, EC values, $SO_4^{2-}$ and $Ca^{2+}$ concentrations were negatively correlated with pH values.

Analysis of Correlation with Cross Sectional Area of Flow and Flow Rate Variation of Discharge Measurement Point in the Upper Stream of Seomjin River (섬진강상류 유량측정지점의 유수단면적과 유량변화에 따른 상관관계 분석)

  • Song, KwangDuck;Kim, KapSoon;Lee, DongJin;Ham, SangIn;Kim, DaeYoung;Oh, TaeYoun;Lee, JaeChoon;Lim, ByungJin
    • Korean Journal of Ecology and Environment
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    • 제46권1호
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    • pp.94-102
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    • 2013
  • This study was carried out to determine the variation of the water level and crosssection area for investigating changes of stream foreland, and to determine the correlation between the average flow velocity and cross-section area so as to understand the hydrological characteristics of the stream. The slope of the cross-sectional area was changed in water levels of 0.6~1.0 m and 1.8~2.0 m. The first change occurred in the low-water level season, and the second change occurred in the high-water level seasons. It is assumed that the changes occurred due to the geological transfigure. The correlation between the cross-sectional area and the average flow velocity was 0.22~0.86 in the exponential equation and 0.20~0.87 in the linear equation. The low water level had a higher correlation than the high water level, and free weirs in the upper stream showed a very low correlation. Therefore, this study provides novel information for the management of water quality in the riverside, using correlation equations of the water level and flow velocity with the cross section area.

A Study on the Characteristic of Pollutants of Water Quality and Sediments in Gul-po Stream Basin (굴포천 유역 내 수질 및 퇴적물의 오염물질 특성 파악에 관한 연구)

  • Ahn, Tae-Woong;Jung, Jae-Hoon;Kim, Tae-Hoon;Kim, Sea-Won;Choi, I-Song;Oh, Jong-Min
    • Journal of Korean Society of Environmental Engineers
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    • 제34권7호
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    • pp.495-503
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    • 2012
  • The water quality of Gul-po Stream, the subject of this study, has been deteriorating because of the inflow of domestic sewage and the industrial wastewater due to industrialization and the problems relating to the structure of river including slow flow rate and the covering of river. In particular, the domestic sewage from small-medium sized factories by the river and large-scale industrial complex by the upper and middle streams of the river, and the domestic sewage from increasing population due to the regional development are the main pollution sources. Thus, this study aims to survey the water quality and the sediment affecting Gul-po Stream; monitor the state of pollution in water body; assess the yield of sediment and investigate the water quality of river and the problems arising from sediment; and then suggest reasonable ways to improve the situation. The findings from surveying pollution load shows the discharge increases up to average 72.8 times from the upper stream to the downstream of Gul-po Stream, and pollution load increases up to: SS 111 times, BOD 150 times, COD 145 times, the nutrient T-N 222 times and T-P 312 times on an average basis. As for the pollution concentration range, ignition loss is 1.29~12.43%; COD is 4,015~37,547 kg/day; T-N and T-P 94.8~352.5 kg/day and 81.8~372.3 kg/day, respectively. As for the releasing rate of sediment, T-N is -14.46~$156.61mg/m^2/day$; T-P is -11.53~$26.10mg/m^2/day$, indicating the likelihood of internal contamination due to the elution of sediment. This study is expected to be used as basic data to manage Gul-po Stream basin.

An Exploratory Study about the Importance of Selected Nursing Activities during the Puerperal Period, as Viewed by Women in the Puerperal Period and by Nurses Caring for Them (산모와 간호원이 본 선택된 산욕기 간호활동의 중요도에 관한 탐색적 연구)

  • 박주봉
    • Journal of Korean Academy of Nursing
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    • 제8권1호
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    • pp.152-162
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    • 1978
  • The desire to maintain health is increasing, consequently the role of nursing which has as one chief aim the solving of man′s basic problems is more and more important. Today, in spite of a growing concern about the nursing activities which nurses provide for individual human having specific needs, clinically in fact, it is questionable that individual′s expectation of nursing activities agrees with nurse′s performance of nursing activities. In this study the importance and agreement of the importance of the nursing activities during the hospitalized puerperal period as viewed by women in the puerperal period and by nurses caring for them, were assessed. The present study was undertaken in an attempt to furnish the basic data for expediting the progress of research activities in this area and further to be helpful in planning maternity nursing practice. The study population defined and selected was nurses (13) caring for women in the puerperal period and doing duty on obstetric & gynecologic ward at Y. hospital, and the women in puerperal period (39) as sum of 3 women selected by each nurse during the period of May 13th-June 4th 1976. The study data was collected by the direct interview method based on the questionnaire which the investigator made out. The study result was analyzed by percentage, t - test. The findings can be summarized as follows: 1. General characteristics of nurses doing duty on puerperal ward: a. Nurses′average age was 24.8 years old. b. 84.6% had educational background of 4 years of college. c. 69.2% had a religion. d. 53.8% were married. e. 53.8% had clinical experience of 1 year -3 years. f, 61.5% did duty on puerperal ward during 1 year -3 years. g. 46.2% desired to do duty on obstetric ? gynecologic ward. 2. General characteristics of the women who were studied during their puerperal period: a. Women′s average age was 26.4 years old. b. 79.5% had educational background above high school. c. 56.4% had a religion. d. 84.6% had living standard above medium. e. 89.7% had no occupation. f, 53,8% had previous hospitalization experience. g. 56.4% had previous delivery experience. 3. Examining the importance of 39 nursing activities during puerperal period selected by investigator, studied group of women considered that the most important nursing activity was "Record precisely about condition, medical treatment and nursing activity results etc". Nurses considered that the most important nursing activity was "Notice whether having pain and care for that". Both groups considered that the least important nursing activity was "Talk with her about topics such as news, hobbies, other interests". 4. Examining the importance of nursing activities in 4 specific categories, studied group of women considered that the most important nursing activity in physical nursing category was "Be sure of safety measure to prevent accidents, injuries", and nurses considered that the most important nursing activity was "Make her sleep and rest sufficiently". Studied group of women considered that the most important nursing activity in psychological category was "Explain about medical treatment and nursing activity ahead of time so she knows what to expect" , and nurses considered that the most important nursing activity was "Explain about puerperal period so she understands". Studied group of women considered that the most important nursing activity in relation to medical care was "Record precisely about condition, medical treatment and nursing activity results etc.", and nurses considered that the most important nursing activity was "Observing, cleaning and protecting the perineum" Studied group of women considered that the most important nursing activity in nursing category in preparation for discharge was "Instruct about personnel hygiene during puerperal period", and nurses considered that the most important nursing activity was "Instruct self-care to protect the perineum". 5. The analysis of this study showed a significant amount of disagreement computed by subtracting the nurse′s score from the patient′s score. Studied group of women put greater importance on physical nursing category, psychological nursing category, nursing in relation to medical care, than the nurses. These results were statistically significant at 0.01 level.

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Development of Rainfall-runoff Analysis Algorithm on Road Surface (도로 표면 강우 유출 해석 알고리즘 개발)

  • Jo, Jun Beom;Kim, Jung Soo;Kwak, Chang Jae
    • Ecology and Resilient Infrastructure
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    • 제8권4호
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    • pp.223-232
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    • 2021
  • In general, stormwater flows to the road surface, especially in urban areas, and it is discharged through the drainage grate inlets on roads. The appropriate evaluation of the road drainage capacity is essential not only in the design of roads and inlets but also in the design of sewer systems. However, the method of road surface flow analysis that reflects the topographical and hydraulic conditions might not be fully developed. Therefore, the enhanced method of road surface flow analysis should be presented by investigating the existing analysis method such as the flow analysis module (uniform; varied) and the flow travel time (critical; fixed). In this study, the algorithm based on varied and uniform flow analysis was developed to analyze the flow pattern of road surface. The numerical analysis applied the uniform and varied flow analysis module and travel time as parameters were conducted to estimate the characteristics of rainfall-runoff in various road conditions using the developed algorithm. The width of the road (two-lane (6 m)) and the slope of the road (longitudinal slope of road 1 - 10%, transverse slope of road 2%, and transverse slope of gutter 2 - 10%) was considered. In addition, the flow of the road surface is collected from the gutter along the road slope and drained through the gutter in the downstream part, and the width of the gutter was selected to be 0.5 m. The simulation results were revealed that the runoff characteristics were affected by the road slope conditions, and it was found that the varied flow analysis module adequately reflected the gutter flow which is changed along the downstream caused by collecting of road surface flow at the gutter. The varied flow analysis module simulated 11.80% longer flow travel time on average (max. 23.66%) and 4.73% larger total road surface discharge on average (max. 9.50%) than the uniform flow analysis module. In order to accurately estimate the amount of runoff from the road, it was appropriate to perform flow analysis by applying the critical duration and the varied flow analysis module. The developed algorithm was expected to be able to be used in the design of road drainage because it was accurately simulated the runoff characteristics on the road surface.

The Study of Radiation Exposed dose According to 131I Radiation Isotope Therapy (131I 방사성 동위원소 치료에 따른 피폭 선량 연구)

  • Chang, Boseok;Yu, Seung-Man
    • Journal of the Korean Society of Radiology
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    • 제13권4호
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    • pp.653-659
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    • 2019
  • The purpose of this study is to measure the (air dose rate of radiation dose) the discharged patient who was administrated high dose $^{131}I$ treatment, and to predict exposure radiation dose in public person. The dosimetric evaluation was performed according to the distance and angle using three copper rings in 30 patients who were treated with over 200mCi high dose Iodine therapy. The two observer were measured using a GM surverymeter with 8 point azimuth angle and three difference distance 50, 100, 150cm for precise radion dose measurement. We set up three predictive simulations to calculate the exposure dose based on this data. The most highest radiation dose rate was showed measuring angle $0^{\circ}$ at the height of 1m. The each distance average dose rate was used the azimuth angle average value of radiation dose rate. The maximum values of the external radiation dose rate depending on the distance were $214{\pm}16.5$, $59{\pm}9.1$ and $38{\pm}5.8{\mu}Sv/h$ at 50, 100, 150cm, respectively. If high dose Iodine treatment patient moves 5 hours using public transportation, an unspecified person in a side seat at 50cm is exposed 1.14 mSv radiation dose. A person who cares for 4days at a distance of 1 meter from a patient wearing a urine bag receives a maximum radiation dose of 6.5mSv. The maximum dose of radiation that a guardian can receive is 1.08mSv at a distance of 1.5m for 7days. The annual radiation dose limit is exceeded in a short time when applied the our developed radiation dose predictive modeling on the general public person who was around the patients with Iodine therapy. This study can be helpful in suggesting a reasonable guideline of the general public person protection system after discharge of high dose Iodine administered patients.