• 제목/요약/키워드: number of researcher

검색결과 361건 처리시간 0.024초

NEAR-FIELD DILUTION OF ROSETTE TYPE MULTIPORT WASTEWATER DIFFUSERS

  • Seo, Il-Won;Yeo, Hong-Koo
    • Water Engineering Research
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    • 제3권2호
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    • pp.93-111
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    • 2002
  • In this paper, mixing characteristics and dilution of the merging buoyant discharges from array of multiple jets has been extensively studied in the hydraulic model experiments. New equations for dilution, which include the merging effects correctly, were derived. Experiments were constructed in a 20-m long, 4.9-m wide and 0.6-m deep flume, and the model diffuser was manufactured to indicate the typical characteristics of the existing ocean wastewater outfall in South Korea. Buoyant discharge from the diffuser was reproduced using heated water. Water temperature was measured using CC-Type thermocouple sensors, which were connected to a 40-channel data logger. Experimental results show that merging between ports in a particular riser is dependent upon the discharge densimetric Froude number, whereas merging between two ports which are facing each other at 90$\circ$ at the adjacent risers is dependent upon the discharge densimetric Froude number and distance from the port and port spacing. Centerline dilution increase with distance from the port outlet until two plumes has merged. However, after merging occurs, increase of the centerline dilution almost stops. Further distance from the position where merging occurs, centerline dilution increases again.

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탄소나노튜브 필름 제조 실험실의 세부작업별 공기 중 나노입자 노출 농도 (Monitoring Airborne Nanoparticle Concentrations by Task in a Laboratory Making Carbon Nanotube Films)

  • 하주현;신용철
    • 한국산업보건학회지
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    • 제20권4호
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    • pp.248-255
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    • 2010
  • Airborne nanoparticle concentrations in three metrics (particle surface area concentration, particle number concentration, and particle mass concentrations) were measured by task in a laboratory making carbon nanotubes (CNTs) films using three direct reading instruments. Because of the conducted other researcher's experiment before the tasks, airborne nanoparticle surface area and number concentrations are the highest at the first time conducted weighing and mixing by sonication task, respectively. Because of the mist generated during mixing by sonication, the highest airborne nanoparticle surface area and PM1 concentrations were measured in the task among the total. Nanoparticle surface area concentrations at the researchers' breathing zones had high correlation (r=0.93, p<0.01) with those measured at an area in the laboratory. This result indicates that nanoparticles generated during the experiment contaminated the whole room air. When the experiment performed all the fume hoods weren't operated and making CNTs films task were conducted in the out of the fume hoods. In conclusion, researchers performing making CNTs film experiments were exposed to airborne nanoparticles generated during the experiment without adequate controls. We recommend that adequate controls should be implemented so that workers' exposures to airborne nanoparticle are limited to minimum levels.

신장운동을 포함한 자조관리프로그램이 섬유조직염환자의 증상완화에 미치는 효과 (Effects of a Self-Help Program including Stretching Exercise on Reduction of Symptom in Patients with Fibromyalgia)

  • 한상숙
    • 근관절건강학회지
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    • 제5권1호
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    • pp.39-56
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    • 1998
  • This study was an quasi-experimental study, done to identify factors Influencing the reduction of symptoms in patients with fibromyalgia. The primary purpose of the study was to develop a Self-Help Program suitable for patients with fibromyalgia in Korea. The secondary purpose was to identify the effects of a Self-Help Program which included stretching exercise. This study was carried out between Feb. 24 and July 8, 1997 and patients in the study Included out patient diagnosed with fibromyalgia based on the criteria developed by the American College of Rheumatology(1990) and H, University which is a tertiary patient care clinic for Rheumatism. The experimental group included 38 patients who were residents of Seoul or Kyungi province, and a control group of 38 patients who were residents of other areas. The control patients were matched to the experimental group patients and they were selected considering the number of tender points on the Fibromyalgia Impact Questionnaire score and a score of self-efficacy. The experimental group participated in a Self-Help Program based on the American Arthritis Foundation(1995) guidelines. The program participants participated in a small group which consisted of 12-15 members attending the program once a week, for 6 weeks with each program lasted two to two and a half hours. The stretching exercise was carried out in each patient's home every day following the video tape exercise provided by the researcher, and the researcher provided encouragement and concern to the patients by calling them once a week. The number times the exercise was performed was divided by the number of participants to calculate the percentage of performance and determine the amount of exercise. Self-efficacy was measured by the Self-Efficacy Scale developed by Lorig et al. (1989) for arthritis patients. The degree of pain was converted to scores based on the Visual Analog Scale, the number of tender points was converted to scores based on the criteria of the ACR(1990) and of Yunus. Depression was measured by CES-D and physical disability, sleep disturbance, fatigue, and anxiety of patients with fibromyalgia were measured by the Fibromyalgia Impact Questionnaire. The level of the exercise performance was converted to scores using the number of times the exercise was performed following the video tape prepared by Association of Rheumatology Health Professionals. Data were analyzed by SPSS windows and the results ire described below. 1. The experimental group which participated in the Self-Help Program showed higher efficacy scores than the control group when both groups were analyzed for depression and the number of tender points as common variables(F=9.146, p=.003). 2. The experimental group which participated in the Self-Help Program showed lower scores than the control group, for pain, the number of tender points, depression, physical disability, fatigue, sleep disturbance and anxiety. These symptoms of fibromyalgia can all be seen to have subsided(F=9.483, p=.003 : F=32.680, p=.001 ; F=11.104, p=.001, F=5.344 : p=.024, F=7.630 : P=.007, F=15.6512, p=.003 : F= 7.5412, p=.008). 3. In the experimental group, the self-efficacy score for the first three weeks showed a positive correlation with the exercise-performance score for four to six weeks (r=.387, p=.043). 4. In the experimental group, the relationship between the level of exercise-performance and the reduction of symptoms showed a significant correlation only to physical disability(r= -.500, p=.001). 5. In the experimental group, the relationship between the self-efficacy score and pain, the number of tender points, depression, physical disability, fatigue, sleep disturbance and anxiety score showed inverse correlations and thus, a reduction of symptoms occured when the self-efficacy score increased(r=-.325, p=.004 ; r= -.253, p=.027, r=-.452, p=.001 : r=-.434, p=.001 ; r=-.316, p=.005 ; r=-.460, p=.001 ; r=-.397, p=.014). Therefore, self-efficacy improved following the Self-Help Program including the stretching exercise. It was also found that physical symptoms (pain, number of tender points, level physical disability) and psychological symptoms (depression, fatigue, sleep disturbance, anxiety) were reduced. Moreover, It was found that the higher the self-efficacy, the the higher the degree of achievement of goals set for the stretching exercises. In addition, the level of exercise-performance influenced the level of physical disability, one of the symptoms of fibromyalgia. Accordingly, the conclusions from this study are that exercise-performance and the reduction of symptoms is achieved through promotion of self-efficacy. Therefore, it is proposed that are the Self-Help Program including stretching exercises is an appropriate nursing intervention for the reduction of symptoms of fibromyalgia.

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Students' Visual Representation of Mathematics

  • Trance, Naci John C.;Marapo, Roger B.;Pornel, Jonny B.
    • 한국과학교육학회지
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    • 제32권8호
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    • pp.1318-1332
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    • 2012
  • This paper takes another approach in assessing students' perception of mathematics. Instead of asking for verbal description of the students' perception of mathematics, we asked the respondents who were all college students to draw their perception of mathematics. This relatively new approach enabled students to take a second look of how they perceived math and, at the same time, explored students' creativity and provided a less austere appearance to mathematics which was taken usually in a more formal and severe manner. This approach of assessing students' perception of mathematics generated new information that could not be normally gleaned from other approaches like Likert Scale. Some drawings of mathematics of the respondents reinforced their math affect towards mathematics. For those who hated math, their drawings revealed so the same is true with those who loved mathematics. Examining the visual representations of mathematics and looking for commonalities, the researcher found a number of interesting themes that may shed some light to educators' understanding of students' math affect.

Arbitration Award via Modern Technical means in Saudi Arabia

  • Mohammed Sulaiman Alnasyan
    • International Journal of Computer Science & Network Security
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    • 제23권7호
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    • pp.32-38
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    • 2023
  • This study deals with arbitration award via modern technical means; because e-Arbitration is deemed to be one of the most important substitute means for the settlement of disputes arising from electronic transactions. This type of arbitration is characterized by fast settlement of disputes, as well as fast enforcement of awards rendered thereon. The researcher seeks to indicate the content of the award, the conditions for rendering it, and to analyze the legal provisions related to its legal basis in the Saudi Law of Arbitration. This study shows that an arbitration award, rendered via modern technical means has a number of advantages, such as fast settlement, less cost, and keeping pace with modern technology, which is an aim of Saudi Arabia Vision 2030. The study also points out certain problems facing arbitration via technical means; however, the most important of which is the insufficiency of some legal rules associated with traditional arbitration, as contained in the Saudi Law of Arbitrator, which are incompatible with or applicable to an arbitration award which is rendered via modern means.

Generation of High-Resolution Precise DEMs Through Airborne LIDAR Surveys on Huge Antarctic Regions

  • Lee Imp-yeong;CHOI Yun-soo;Lee, Jae-one
    • Korean Journal of Geomatics
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    • 제3권2호
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    • pp.115-122
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    • 2004
  • NASA, NSF and USGS jointly conducted airborne LIDAR surveys to acquire numerous surface points with high densities over the Antarctic Dry Valleys and its vicinity, The huge set of these points retains two characteristics undesirable for DEM generation, which are unusually high blunder ratio and large variation of the local point densities. Hence, in order to not only reduce the undesirable effects due to these characteristics but also process the huge number of points within reasonable limits of time and resources, we developed an efficient, robust, nearly automatic approach to DEM generation. This paper reports about the application of this approach to generating high-resolution precise DEMs from the Antarctic LIDAR surveys and the evaluation of their accuracy.

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관개조직의 수명기간 신뢰성 해석 (Lifetime Reliability Analysis of Irrigation System)

  • Kim Han-Joong;Lee Jeong-Jae;Im Sang-Joon
    • 한국농공학회지
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    • 제45권2호
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    • pp.35-44
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    • 2003
  • A system reliability method is proposed to decide reliable serviceability of agricultural irrigation system. Even though reliability method is applied to real engineering situations involving actual life environments and maintaining costs, a number of Issues arise as a modeling and analysis level. This article use concepts that can be described the probability of failure with time variant and series-parallel system reliability analysis model. A proposed method use survivor function that can simulate a time-variant performance function for a lifetime before it is required essential maintenance or replacement to define a target probability of failure in agricultural irrigation canal. In the further study, it is required a relationship between a state of probability of failure and current serviceability to make the optimum repair strategy to maintain appropriate serviceability of an irrigation system.

Construction of Scientific Impact Evaluation Model Based on Altmetrics

  • Li, Jiapei;Shin, Seong Yoon;Lee, Hyun Chang
    • Journal of information and communication convergence engineering
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    • 제15권3호
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    • pp.165-169
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    • 2017
  • Altmetrics is an emergent research area whereby social media is applied as a source of metrics to evaluate scientific impact. Recently, the interest in altmetrics has been growing. Traditional scientific impact evaluation indictors are based on the number of publications, citation counts and peer reviews of a researcher. As research publications were increasingly placed online, usage metrics as well as webometrics appeared. This paper explores the potential benefits of altmetrics and the deep relationship between each metrics. Firstly, we found a weak-to-medium correlation among the 11 altmetrics and visualized such correlation. Secondly, we conducted principal component analysis and exploratory factor analysis on altmetrics of social media, divided the 11 altmetrics into four feature sets, confirming the dispersion and relative concentration of altmetrics groups and developed the altmetrics evaluation model. We can use this model to evaluate the scientific impact of articles on social media.

Parametric Macro for Two-Dimensional Layout on the Auto-CAD System

  • Kim, Yunyoung;Park, Jewoong
    • Journal of Ship and Ocean Technology
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    • 제4권3호
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    • pp.13-20
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    • 2000
  • In recent years, a number of successful nesting approaches have been developed by using the various heuristic algorithms, and due to their application potential several commercial CAD/CAM packages include a nesting module for solving the layout problems. Since a large portion of the complexity of the part nesting problem results from the overlapping computation, the geometric representation is one of the most important factors to reduce the complexity of the problem. The proposed part representation method can easily handle parts and raw materials with widely varying geometrical shape by using the redesigning modules. This considerably reduces the amount of processed data and consequently the run time of the computer. The aim of this research is to develop parametric macro for two-dimensional layout on the Auto-CAD system. Therefore, this research can be called "pre-nesting".ing".uot;.

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법규적 측면에서 고찰한 고층 건축물 공사현장 화재안전 확보방안 (A Study on the Improvement of Fire Safety in high-rise Building Construction in Legal aspects)

  • 박찬석;정일균
    • 대한안전경영과학회지
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    • 제17권1호
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    • pp.21-32
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    • 2015
  • High rising of the buildings offers a number of risk factors than ever before with regard to fire prevention. Especially in the construction site of high-rise buildings, people waste golden-time during the evacuation because temporary fire fighting facilities are not installed and transferred to a large fire because of fire suppression failure. In this study, the researcher derives the problems of fire protection in high-rise buildings construction sites and proposed the measures in such the legal aspects as fire building construction code and etc. There are the legal improvements such as orders of construction suspension in the problems of fire safety, appointing fire safety manager, temporary fire protection installation standards, enhancing penalty provisions regarding the use of fire, operating self fire brigade, confirming on-site after completing fire-protection facalities, establishment or strengthening special fire-protection investigations.