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Analysis to Select Filter Media and The Treatment Effect of Non-point Pollution Source in Road Runoff

  • Lee, Tae Goo;Han, Young Hae
    • KIEAE Journal
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    • v.14 no.3
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    • pp.55-63
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    • 2014
  • This study selected and analyzed filter media that can be applied in non-point pollution reduction devices aimed at processing the source of pollution on site for road runoff that increases rapidly in rainfall-runoff in order to improve the water quality of urban areas. First, the factors that affect the quality of runoff caused by sources of non-point pollution include physical and social factors such as the usage of land around the area of water collection, type of pavement and movement of cars and people, as well as rainfall characteristics such as frequency, intensity, amount and duration of rainfall. Second, the purification tests of the filter media were processed for pH, BOD, COD and T-P, and the filter media showed to have initial purification effect at that items. However, the filter media showed to be very effective for the processing of SS, T-N, Zn and Cd from the beginning to the end. Third, for filter media, zeolite and vermiculite showed to be effective for processing SS, T-N, Zn and CD constantly, and composite filter media including zeolite showed to have strong processing effects. The authors conclude that this study can be applied to technical areas and policies aimed at reducing non-point pollution in urban areas and can also contribute to allowing eco-friendly management of rainfall as well as improvement of water quality.

A Study on Accelerated Photo-Degradation Test for Lifetime Estimation of Ink-jet Ink (잉크젯 잉크의 수명예측을 위한 광열화 가속시험법에 관한 연구)

  • Koo, Hyun-Jin;Cho, Hang-Won;Ji, Byung-Chul
    • Journal of Applied Reliability
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    • v.15 no.3
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    • pp.154-162
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    • 2015
  • We have performed accelerated photo-degradation test using a 10-Sun level high irradiance $Weather-Ometer^{(R)}$ (10-Sun Ci5000) in an attempt to study acceleration and correlation between accelerated and service conditions for ink-jet ink. The accelerated test was used to predict lifetimes of ink-jet ink through the calculation of scaling factor for intensity of irradiance and duration of usage combined with estimation of lifetime distribution and inverse power model as a life-stress model. The lifetimes and acceleration factors for foreign and domestic inks were compared with each other. The results showed that the failure mechanisms and life-stress models for ink-jet ink were different among the color of ink which means that we might be in need of further study by color of inks.

Analysis of the Correlation between Climatic Elements and Electricity Generation of Building Integrated Photo Voltaic on Gymnasium Building's Curtain Wall (체육관 커튼월에 설치된 건물일체형 태양광발전시스템의 발전량과 기후 요소 간의 상관성 분석)

  • Park, Kang-Hyun;Lee, Jeong-Hun;Kim, Su-Min;Park, Kyung-Won
    • Journal of the Korean Solar Energy Society
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    • v.32 no.1
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    • pp.8-14
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    • 2012
  • Concerning about global warming due to emission of greenhouse effect gas like C02 and depletion of fossil fuels have been spreading. So the need for solar energy utilization is increased. It is essentially important to make efforts to reduce usage of fossil energy resources. In this study, we analyzed the correlation between climatic elements and the photovoltaic power generation. Cloud cover of the correlation coefficient was 0.93. The order of the correlation coefficient was average temperatures, hours of sunshine duration of sunshine and the humidity. To accurately analyze of the degree of correlation for the photovoltaic power generation, additional research about climatic elements that show a high correlation is needed.

A Study on Difference of Internet Game Addiction Tendency According to The Game with Use (인터넷 게임 사용 실태에 따른 게임 중독 경향의 차이에 관한 연구)

  • Choung, Hye-Myoung;Lee, Dong-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.2
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    • pp.159-166
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    • 2008
  • The purpose of this study is to examine the usage of time for internet game in students of college and analyse the addiction and verify the relation between elements of the capacity of self-control and internet game addiction. The result show that the use time and the duration of daily internet game have influence on the internet game addiction(p<0.05) and also show that they have highly influence(+) on the relation elements of self-control : the trouble of studies, the loss of human relation, the confusion between the real and virtual, and the escapism.

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Strength characteristics of granulated ground blast furnace slag-based geopolymer concrete

  • Esparham, Alireza;Moradikhou, Amir Bahador;Andalib, Faeze Kazemi;Avanaki, Mohammad Jamshidi
    • Advances in concrete construction
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    • v.11 no.3
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    • pp.219-229
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    • 2021
  • In recent years, geopolymer cements, have gained significant attention as an environmental-friendly type of cement. In this experimental research, effects of different alkaline activator solutions and variations of associated parameters, including time of addition, concentration, and weight ratio, on the mechanical strengths of Granulated Ground Blast Furnace Slag (GGBFS)-based Geopolymer Concrete (GPC) were investigated. Investigation of the effects of simultaneous usage of KOH and NaOH solutions on the tensile and flexural strengths of GGBFS-based GPC, and the influence of NaOH solution addition time delay on the mechanical strengths is among the novel aspects investigated in this research. four series of mix designs and corresponding specimen testing is conducted to study different parameters of the active alkali solutions on GPC mechanical strengths. The results showed that addition of NaOH to the mix after 3 min of mixing KOH and Na2SiO3 with dry components (1/3 of the total mixing duration) resulted in the highest compressive, tensile and flexural strengths amongst other cases. Moreover, increasing the KOH concentration up to 12 M resulted in the highest compressive strength, while weight ratio of 1.5 for Na2SiO3/KOH was the optimum value to achieve highest compressive strengths.

The Distribution of Information Sources within the University Selection Decision-Making Process: A Longitudinal Study

  • LE, Tri D.;NGUYEN, Tan T.;NGUYEN, Phuong N.D.;NGUYEN, Thi Quynh Trang
    • Journal of Distribution Science
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    • v.20 no.11
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    • pp.89-98
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    • 2022
  • Purpose: Increasing competition in the higher education sector has prompted universities to enhance their marketing efforts and understand their potential customers. The study aims to explore how information sources are used and changed among prospective Vietnamese students during the decision-making process. Research Design, Data, and Methodology: This study undertakes a longitudinal study involving multiple rounds of data collection to better understand the decision-making process of prospective students. Data was collected from 12th -grade students in Vietnam through two rounds of quantitative surveys with 251 students and one round of qualitative interviews, spanning the duration of their senior year. The three stages of the decision-making process correspond to the three stages of pre-purchase period. Results: Most students decide that attending open days, taking career assessments, and looking up information online are the most important information sources to consider. The WOM sources are more important in the early stages, while university-generated sources and events are important in the later stages. Conclusion: Implications from this study may contribute to the design of more effective marketing communications campaigns as university marketers gain a better understanding of the distribution of information sources utilized for each specific stage of the decision-making process.

A study on the menstrual patterns and menstrual discomforts in women university students (일부 여대생들의 월경양상과 월경시 불편감에 관한 조사연구)

  • Lee In Sook
    • Journal of Korean Public Health Nursing
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    • v.12 no.1
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    • pp.116-131
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    • 1998
  • This study was undertaken to obtain the menstrual patterns and menstrual discomforts in women university students. For the data collection, self-administered questionnaire survey was made from December 10, 1996 to January 20, 1997 among the 180 women university students in Seoul. The resultant data were processed by SAS program for frequency, proportion, and chi-square test. The results of this study are as follows ; 1) The mean age of the subjects was 20.6 years old. The mean height was 162cm and weight was 52.3Kg. $26.9\%$ of the subjects responded that they had experienced the unbalanced diet, $56\%$ the irregular meal, $39.6\%$intermittent dizziness, and $63.4\%$ the premenstrual syndrome. $53.7\%$ had feeling that skin temperature of their four extremities was 'a little lower than others'. The mean BMI(Body Mass Index) was 19.8, 'normal level' was $41.8\%$. $18.7\%$ responded that their characters were 'introspective ones'. The mean age of menache was 13.8 years old. The subjects responded that the mean number of pads they used per day during menstrual periods was 4.6 sheets. The mean duration of menstruation was 5.4 days, $10.4\%$ responded that their menstrual cycles were 'extremely regular', $44.8\%$ was 'regular', $36.6\%$ was 'a little irregular', and $8.2\%$ was 'extremely irregular'. Out of them who had experienced the dysmenorrhea, $21.3\%$ had family history of dysmenorrhea in connection with their mother and $35.0\%$ in their sisters. The mean of the first time that they experienced dysmenorrhea was 15 years old. $94\%$ of the subjects responded that they had experienced the dysmeorrhea. $47.6\%$ of the subjects responded that they experienced the dysmenorrhea 'monthly' and $52.4\%$ 'intermittently'. $53.0\%$ of them who had experienced dysmenorrhea responded that dysmenorrhea was the severest 'on the first menstrual day' and $22.4\%$ 'on the second day'. $48.8\%$ of them who had experienced dysmenorrhea responded that the most painful region was 'low abdomen'. $40\%$ of them who had experienced dysmenorrhea responded that they used 'analgesics' to soothe dysmenorrhea, $24.8\%$ used nothing, $18.4\%$ lay in their beds or slept, and $12\%$ made their 'low abdomen' warm. $70.3\%$ who had used analgesics because of dysmenorrhea took analgesics 'one or two times per month', $25.7\%$ 'intermittently', and $4.0\%$ more than 3 times per month. The analgesics which they used were 'geworin$(33.8\%)$,' 'penzal$(32.4\%)$', 'tyrenol$(18.9\%)$', and 'aspirin$(4.2\%)$'. $(47.9\%)$ of them who took analgesics because of dysmenorrhea responded that the duration of analgesics effect was '4 to 8 hours'. $15.1\%$ of them who experienced dysmenorrhea responded that they had visited the hospital. 2) The incidence of premenstrual syndrome was no significant difference according to the BMI, unbalanced diet, pattern of meal, skin temperature of four extremites, and characters. 3) The incidence of dysmenorrhea was significant difference according to the BMI, unbalanced diet, pattern of meal, skin temperature of four extremites, and characters. 4) The incidence of analgesics usage was significant difference according to the BMI, subjects with low BMI took more analgesics than those with normal BMI (p<.05). The incidence of analgesics usage was significant difference in accordance with pattern of meal. The women who had a meal regularly took more analgesics than those who had a meal irregularly(p<.05). But the incidence of analgesics usage was no significant difference in accordance with the unbalanced diet, characters, the incidence of dizziness, skin temperature of four extremities, the incidence of premenstrual syndrome.

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Use of herbal medicine in epileptic children (소아 간질 환자에서 한약 복용 실태)

  • Lee, Jee Yeon;Choi, Wook Sun;Eun, So-Hee;Eun, Baik-Lin;Hong, Young Sook;Lee, Joo Won
    • Clinical and Experimental Pediatrics
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    • v.51 no.4
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    • pp.415-419
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    • 2008
  • Purpose : Herbal medicine is thought to be widely used by children with epilepsy, but there have been few studies. This study aimed to investigate the perceptions and the actual conditions of usage of herbal medicine by children with epilepsy. Methods : From July to August 2007, three hundred seventy eight questionnaires were completed by parents of epileptic children who visited pediatric neurology clinic of Korea University hospital and Kwangmyung-Sungae hospital. Demographic data and patterns of usage of herbal medicine were investigated. Results : Among 378 patients, sixty five (17.2%) reported using herbal medicine. Major reasons for using herbal medicine were 'to enhance general health' and 'belief that it has fewer side effects'. Majority of respondents did not notify their physician about using herbal medicine because 'they did not need to share this with doctor' and 'they thought their doctor would disapprove'. After taking herbal medicine, 33.3% of patients reported that it did not benefit their seizure but they felt healthier. Usage of herbal medicine was significantly related to number of AEDs (antiepileptic drugs), duration of AED treatment, association with psychosomatic disorders and motivation by other people or by mass media. Conclusion : Considerable numbers of epileptic children were using herbal medicine during treatment with AED and did not inform their physician about usage of it. Physicians should be aware of benefits and harms of herbal medicine and actively intervene in the usage of herbal medicine by epileptic patients.

Risk Factors for Nosocomial Pneumonia in Patients at NS ICU (신경외과 중환자실의 병원성 폐렴 발생 위험요인)

  • Kim Nam Cho;Kim So Yeon
    • Journal of Korean Public Health Nursing
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    • v.15 no.2
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    • pp.239-248
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    • 2001
  • The purpose of this study was to analyze risk factors for nosocomial pneumonia in patients admitted to NS ICU, and to provide a basic data to decrease respiratory nosocomial infection rate engendered from medical environments in NS ICU. The study site was the NS ICU at a university hospital located in Seoul, Korea. The subjects were 31 patients diagnosed with nosocomial pneumonia, who were selected from the initial list of 300 potential subjects who had been a) admitted between September 1999 and January 2000, and September 2000 and January 2001, b) resided at the NS ICU over 72 hours. The diagnostic standard of nosocomial pneumonia was based on the nosocomial infection guides of C university hospital. The data were analyzed using frequencies and logistic regression analysis. The sputums obtained from the subjects were cultivated and causal viruses were separated. The results were as follows: 1. The nosocomial pneumonia rate was $10.3\%$. There were 7 types of causal viruses separated from the sputum. and the most prevalent type of virus was MRSA as $62.2\%$. 2. The factors significantly influencing the incidence of nosocomial pneumonia included age, the residential duration at the NS ICU, GCS scores, diabetes mellitus, insertion of tracheal tube and its duration, tracheostomy and its length of insertion, the use of artificial ventilator and the length of its use, and the insertion of naso-gastic tube. The most significant risk factor among these was the insertion of tracheal tube (odds ratio=18.684. $95\%$ CI=6.849-50.974), followed by the use of tracheostomy (odds ratio=15.419, $95\%$ CI=6.615-35.942), the insertion of naso-gastric tube (odds ratio=14.875, $95\%$ CI=6.396-34.595), and the use of artificial ventilator (odds ratio=13.000. $95\%$ CI=5.633­30.001). 3. Regarding the use of the mechanical aids, the insertion of tracheal tube resulted in 12.968 times increase of the nosocomial pneumonia rate, and the use of artificial ventilator lead 6.714 times increase of the nosocomial pneumonia rate. One point increase of the GCS score resulted in the 1.210 times increase of the nosocomial pneumonia rate. For patients who had tracheal tube, tracheostomy, and artificial ventilator, one day increase of their residential duration at NS ICU lead 1.073 times increase of the nosocomial pneumonia rate. 4. In terms of duration of the mechanical aid usage, one day increase in the use of artificial ventilator engendered 1.080 times increase in the nosocomial pneumonia rate. One day increase of the residential duration at the NS ICU lead 1.604 times increase in the nosocomial pneumonia rate. As one point of the GCS score increased, 0.876 times decrease of the nosocomial pneumonia rate was reported. These study findings show that the risk factors significantly influencing the incidence of nosocomial pneumonia include the use of tracheal tube, tracheostomy, naso-gastic tube, and artificial ventilator. It is recommended that nurses working at NS ICU should pay more attention to the patients with these factors as the risky group for the nosocomial pneumonia, and thus make more active efforts to provide nosocomial pneumonia prevention strategies for them. In further studies patients admitted to the different types of ICUs such as internal medicine or surgery unit ICU will be also included, and more wide investigation of nosocomial pneumonia risk factors will be conducted through one-year longitudinal follow up.

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Review of Randomized Controlled Trials on Ideal Acupuncture Treatment for Degenerative Knee Osteoarthtritis (RCT논문을 중심으로 한 퇴행성 슬관절염 침구 치료 방법에 대한 고찰)

  • Kim, Eun-Jung;Lee, Seung-Deok;Jung, Chan-Yung;Yoon, Eun-Hye;Jang, Min-Gee;Nam, Dong-Woo;Kim, Hyun-Wook;Lee, Eun-Yong;Kim, Kyung-Ho;Lee, Geon-Mok;Lee, Jae-Dong;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.26 no.2
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    • pp.125-145
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    • 2009
  • Objectives : To analyze the inclusion criteria of participants, control group interventions, and the results of prior studies of acupuncture for OA. Also to identify aspects of the procedure that are associated with positive outcomes in order to establish ideal acupuncture treatment model. And to assess the methodological quality of the trials with modified Jadad score and FEAS in order to evaluate the quality of prior studies and find out whether or not acupuncture has a positive effect in treating OA. Methods : Articles up to the date of November 2008 were searched via computerized databases of PubMed, Journal of Korean Oriental Medicine, The Journal of Korean Acupuncture & Moxibustion Society and Journal of Oriental Rehabilitation Medicine. Bibliographies of reviewed papers were also searched and reviewed. Only randomized controlled trials (RCTs) and systematic reviews concerning the effects of acupuncture or electroacupuncture (EA) on symptoms of osteoarthritis of the human knee, published in English and Korean were included. The acupuncture treatment methods of the reviewed trials were assessed based on STRICTA. And the methodological quality of the trials was assessed by modified Jadad score and FEAS. Results : Twenty one trials of acupuncture for OA were analyzed. Based on the results of this review the following factors might contribute to optimal results from acupuncture treatment. 1) Usage of $ST_{35}$, $GB_{34$, $EX_{32}$, $ST_{36}$ and $SP_9$ acupuncture points. 2) More than four acupuncture points should be used. 3) More than 15 minutes of needle retention time. 4) Needle length-40mm and diameter-0.30mm 5) Usage of EA 6) more than 10 times treatment 7) Treatment frequency of more than once a week, 8) Treatment duration longer than 6 to 8 weeks. Conclusions : High quality clinical trials of Acupuncture for OA is still in lack. Future investigators must concentrate their attentions on the quality of acupuncture treatment itself used in the trials as well as the methodological quality of trials.

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