• 제목/요약/키워드: experimentals

검색결과 30건 처리시간 0.035초

중학교 환경교육 학습방안에 관한 사례 비교 연구 (A Comparative Case Study on the Environment Lesson in a Middle School)

  • 김미정;조영민
    • 한국환경교육학회:학술대회논문집
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    • 한국환경교육학회 2005년도 후반기 학술대회 발표논문집
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    • pp.138-147
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    • 2005
  • In the present study, the middle school students' perception on the environment course was surveyed before and after three different lessons. It was found that most students were taking environment related issues mainly from mass media including internet and broadcasting. The young students were satisfied at practical experiments, but at the same time a few old fashioned experimental programs would not be preferred. Utilization of multimedia such as audio-visual tools was one of the effective tools for the environment class, because it could help to understand even the profound principles of the chemical and physical processes. However, some students did not concentrate on the display, causing frequent disturbance of the class. Since the school for this investigation did not choose the environment as a selective course, practical tools and materials for the experiment should not be sufficient, and thereby a further detailed work must be followed with the students who are taking environment lessons.

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The Rheological and Mechanical Model for Relaxation Spectra of Polydisperse Polymers

  • Kim, Nam Jeong;Kim, Eung Ryul;Hahn Sang Joon
    • Bulletin of the Korean Chemical Society
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    • 제13권4호
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    • pp.413-419
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    • 1992
  • The theoretical equation for the relaxation spectrum of nonlinear viscoelastic polymeric material was derived from the Ree-Eyring and Maxwell non-Newtonian model. This model consists of infinite number of hyperbolic sine law Maxwell elements coupled in parallel plus a spring without a dashpot. Infinite number of nonlinear viscoelastic Maxwell elements can be used by specifying distribution of relaxation times, hole volumes, molecular weights, crystallite size and conformational size, etc. The experimentals of stress relaxation were carried out using the tensile tester with the solvent chamber. The relaxation spectra of nylon 6 filament fibers in various electrolytic solutions were obtained by applying the experimental stress relaxation curves to the theoretical equation of relaxation spectrum. The determination of relaxation spectra was performed from computer calculation.

퉁퉁마디(Salicornia herbacea L.)에서 추출한 적자색 색소의 특성 및 안정성 (Characteristics and Stability of Violet Red Pigment Extracted from Salicornia herbacea L.)

  • 이영재;박인배;김해섭;신궁원;박정욱;조영철
    • 한국식품영양과학회지
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    • 제38권7호
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    • pp.885-891
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    • 2009
  • 퉁퉁마디의 적자색 색소의 안정성에 대한 pH, 당, 유기산, ascorbic acid, 아미노산, 식염 및 온도의 영향을 조사하였다. 퉁퉁마디 적자색 색소는 pH $4{\sim}6$ 범위에서 가장 안정하였으며, 저장기간에 따른 퉁퉁마디 적자색 색소의 잔존율은 다양한 당 첨가에 의해 대조구에 비해 높았다. 특히, 저장기간 10일 경과 후 0.5 M sucrose를 첨가한 시료구는 대조구에 비해 약 11.1% 가량 색소 잔존율이 높았으며 다음으로 fructose, maltose, glucose, galactose 순이었다. 또한, 유기산의 첨가로 종류와 농도에 관계없이 모두 대조구에 비해 저장기간 중 퉁퉁마디 적자색 색소의 잔존율을 감소시켰으며 특히, 유기산의 농도를 0.5 M로 가장 높게 처리한 시료구의 색소잔존율이 저장 10일 후 $13.1{\sim}15.9%$로 크게 감소하였다. 저장기간 10일 경과 후 ascorbic acid와 thio urea를 동시에 1,000 ppm씩 첨가한 경우 저장 10일 경과 색소의 잔존율이 48.4%로 대조구에 비해 약 23.1% 가량 높았다. 또한 아미노산 중에서는 aspartic acid를 50 mM 처리 시 색소 잔존율이 41.5%로 가장 높았으며 식염의 농도를 2.0 M 처리 시 색소의 잔존율이 31.6%로 대조구에 비해 높았다. $5^{\circ}C$$25^{\circ}C$ 등 저온저장의 경우 색소의 안정성이 유지된 반면 저장온도가 상승함에 따라 색소의 안정성은 급격히 감소하였다.

간호행정학회지의 연구동향 (Review of the Journal of Korean Nursing Administration Academic Society and its research trends)

  • 고명숙;하나선
    • 간호행정학회지
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    • 제7권3호
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    • pp.561-569
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    • 2001
  • This study was designed to analyze all the papers that were in the Journal of the Korean Nursing Administration Academic Society from the first publication edition (1995) to 2000. Analyses methods are research designs, data collection methods, research subjects and key words. all papers were 145. The results of the study are as follows : First, research designs, nonexperimentals are 106 papers, experimentals are 9, qualitatives are 9 papers. Research subjects that all subjects in each paper were accepted are as follows, hospital staffs including nurses, doctors, and other employees are 115 paper(59.28%), adults including patient's family, medical, nursing students are 44 papers(22.68%), informatic systems including medical record sheets, database, and management system are 8 papers(4.12%), others including country, literature, researches are 21 papers(10.82%). Second, data collection methods that all methods in each paper were accepted that questionnaires are 93 papers(57.76%), interviews are 13 papers(8.07%), observations are 10 papers(6.21%), scale & psycholgical are 8 papers(4.97%), and self-reportings are 6 papers(3.73%), etc. Conclusion : Even though research topics are various, the fields of informatics and financial management are poor. Therefore studying for those fields and its practical implication are needed.

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남성의 매력성, 성공성 및 직업적 추론이 가능한 의복과 인물의 특징에 관한연구 (Effects of Men's Clothing Styles and Facial impressions on Attractiveness and Occupational Status.)

  • 이인자
    • 복식
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    • 제29권
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    • pp.127-142
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    • 1996
  • The purpose of this study was to Inferr the attractiveness and Men's occupational Status by facial Impressions and Clothing Styles. The Study was consist of experimentals methods. The experiments developed a set of stimuli and response scales which was pro-fessional suits(C1) general clerical position suits(C2) small business suits(C3) artist at-tire(C4) student attire(C5) The impression of stimuli were measured by means of semantic-duffernential scales an open-ended questionnaire and data was processed ANOVA Duncan's multiple range tes and x2-test. Judging the effects of occupational charaoteristics the experiment was designed in the between-subject design. The subject were 30 male and female who were divided 25 experimental groups as arranging 12 subjects. The conclusions of this study are as follows. 1)Facial characteristics affect the attract iveness and occupational status. 2) Clothing styles affects the inferrence men's attractiveness and occupational status. 3) Perceives inferrence of occupational status affect more impression of the high levels positions person and artist person. 4) High quality texiles deep yellow color suits are perceived high levels positions and white knit jacket and check printed slacks are judged Artist. 5) Artistically characterized person is perceived only artist even change any types of cloth.

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키틴의 염료 흡착에 의한 염액의 색도제거에 관한 연구 -직접염료의 염액을 중심으로- (Decolorization in Dyebath by Dye Adsorption of Chitin -Effects on the Adsorption in Direct Dyebath-)

  • 유혜자;김정희;이혜자;이전숙
    • 한국염색가공학회지
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    • 제13권1호
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    • pp.38-44
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    • 2001
  • The adsorption ability of dyes on chitin, a natural polymer was investigated for decolorization of dye wastewater. Chitin was manufactured in lab by decalcification in dilute aqueous hydrochloric acid solution and deproteination in dilute aqueous sodium hydroxide solution with shrimp shells. Absorbance of residue solution of dyebaths after dye adsorptions of chtin were measured in varieties of dye concentration and dipping periods. Three kinds of Direct dyes -C.I. Direct Red 81 (red 81), C.I. Direct Brown l(brown 1) and C.I. Direct Green 26(green 26) - were used. Red 81 and brown 1 have smaller molecular weight than green 26. The results from experimentals were of]tamed as follows: 1) Adsorption of green 26 was improved in dyebath by addition of salt, but red 81 and brown 1 were not found any improvements. 2) Smaller size of chitin particles could be absorbed much more speedy. In this experiments, the smallest range of chitin particle size was $250\mu{m}$ and less. 3) The most efficient amount of chitin for 20m1 of dyebath was 0.2g, 4) Both of red 81 and brown 1 showed good and speedy adsorption abilities as dyestuffs of over 90 percent in just one minute in dyebath of 0.01% dye concentration. But green 26 was absorbed slowly because of its large molecular weight. It took 40minutes to absorb dyestuffs of over 90 percent in dyebath of 0.01% dye concentration.

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입자의 크기와 유속에 따른 섬유질 여과포에 의한 부유입자 제거 연구 (Removal of Aerosol Through Fibrous Filter as a Function of Particle Size and Velocity)

  • Sang Hoon Lee;Kwan Sik Chun;Hoo Keun Lee
    • Nuclear Engineering and Technology
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    • 제16권1호
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    • pp.29-35
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    • 1984
  • 유리섬유 여과포에 의한 0.1~0.45$\mu\textrm{m}$ 크기의 DOP 부유입자의 제거효율시험을 1~10cm/sec의 유속범위에서 수행하였다. 섬유여과포에 의한 미세입자의 여과는 여과속도에 의하여 결정되는데, 최소제거 효율을 나타내는 DOP 입자의 크기는 여과속도가 증가함에 따라 감소한다. Kuwabara Cell Model과 Von Mises Transformation을 사용하여 유리섬유 여과포내에서 화산에 의한 입자 제거효율을 수치해석적으로 전개하여 구하였으며, 이 계산치는 실험치와 잘 일치하였다. 본 실험의 결과는 여과포의 입자제거효율을 예측하고 최적 운전조건을 추구하는데 기여할 수 있을 것이다.

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대기 혼합층 발달 과정의 모형 실험과 수치 해석 (Laboratory Experimentals and Numerical Analysis for Development of a Atmospheric Mixed Layer)

  • 이화운
    • 한국환경과학회지
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    • 제2권1호
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    • pp.17-26
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    • 1993
  • The layer that is directly influenced by ground surface is called the atmospheric boutsdary layer in comparison with the free atmosphere of higher layer. In the boundary layer, the changes of wind, temperature and coefficient of turbulent diffusion in altitude are large and have great influences an atmospheric diffusion. The purpose of this paper is to express the structure and characteristics of development of mixed layer by using laboratory experiment and numerical simulation. Laboratory experiment using water tank are performed that closely simulate the process of break up of nocturnal surface inversion above heated surface and its phenomena are analyzed by the use of horizontally averaged temperature which is observed. The result obtained from the laboratory experiment is compared with theoretical ones from ; \textsc{k}-\varepsilon numerical model. The results are summarized as follows. 1) The horizontally averaged temperature was found to vary smoothly with height and the mixed layer developed obviously being affected by the convection. 2) The mean height of mixed layer may be predicted as a function of time, knowing the mean initial temperature gradient. The experimental values are associated well with the theoretical values computed for value of the universal constant $C_r$= 0.16, our $C_r$ value is little smaller than the value found by Townsend and Deardoru et al.

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직류전류 주입법에 의한 벡터제어 유도전동기의 회전자 시정수 보상 (Rotor Time Constant Compensation for Vector-Controlled Induction Motor with DC Current Injection Method)

  • 이경주;이득기;정종진;최종우;김흥근;노의철;전태원
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제51권2호
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    • pp.69-76
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    • 2002
  • To obtain a high performance in a vector controlled induction motor, it is essential to know the instantaneous position of the rotor flux which depends on the rotor time constant. But the rotor time constant mainly varies due to the temperature rise in the motor winding, so real time compensating algorithm is necessary. This paper proposes that it uses short duration pulses added to the constant flux command current and then resultant torque command current produced by speed controller is utilized for the rotor resistance estimation. This method has advantage with a low computational requirement and does not require voltage sensors. The proposed method is proved by simulations and experimentals.

수용성조영제의 주입이 가토악하선조직에 미치는 영향에 관한 전자현미경적 연구 (ULTRASTRUCTURAL STUDY ON THE EFFECTS OF RETROGRADE INFUSION OF WATER-SOLUBLE CONTRAST MEDIA ON THE RABBIT SUBMANDIBULAR GLAND)

  • 김은경;박태원
    • 치과방사선
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    • 제17권1호
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    • pp.123-135
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    • 1987
  • The author observed the effects of retrograde infusion of water soluble contrast media (Tele- brix 30) on the rabbit submandibular glands and compared the effects of different degrees of filling. 26 rabbits were divided into 2 groups of 12 each as experimentals and I group of 2 as normal controls. One experimental group was filled with 0.2㎖ and the other with 0.4㎖. Right submandibular gland of each rabbit was infused with contrast media and left one with physiologic saline as a experimental control, at a constant rate of 0.12㎖/min. using an infusion pump via the main excretory duct. Immediately after the infusion of contrast media, oblique lateral radiographs of the glands were made with occlusal film in order to confirm the glandular filling. The rabbits were sacrificed after varying periods (1, 8, 24 hours and 3, 6, 10 days) and the tissues were prepared for light and electron microscopic examination. The results were as follows: 1. In glands filled with 0.2㎖ contrast media, the initial changes were a few vacuole formation in the acini and slight dilation of the intralobular duct. The moderately severe changes such as vacuole formation in the acini, the abnormal substructure within the secretory granule, dilation of acinar and intercalated duct lumen, scalloping of striated duct lumen and inflammatory cell infiltrate were observed at 3 days. The general appearance was successively recovered, so the tissue had a normal appearance at 10 days. 2. In glands filled with 0.4㎖ contrast media, the most prominent alterations such as severe acinar atrophy, decreased number of secretory granules, proliferation of connective tissue stroma and pronounced inflammatory cell infiltrates appeared at 6 days. Although the general appearance returned to be almost normal at 10 days, acinar cells showed some atrophy and decreased secretory granules. 3. In glands subjected to 0.4㎖ infusion, the alterations were more severe and the recovery was slower than those seen in the glands to 0.2㎖ infusion.

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