• 제목/요약/키워드: PP&E

검색결과 241건 처리시간 0.021초

웹기반 협동학습시스템의 활용에 관한 연구 (A Study on the Web Based Collaborative Learning Systems)

  • 이동훈;이상곤;이지연
    • 한국실천공학교육학회논문지
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    • 제2권1호
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    • pp.64-70
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    • 2010
  • 본 연구는 학생들이 온라인 환경에서 정보시스템을 활용하여 효율적인 협동학습을 수행하는 방법을 이해하고자 한다. 이러한 연구목적을 달성하기 위하여 분해된 계획 행동 이론(Decomposed TPB)을 기반으로 하여, 학생들의 웹기반 협동학습시스템의 사용의도에 영향을 미치는 5개의 중요한 요인을 도출하였다: 명시적 사회적 영향, 암시적 사회적 영향, 지각된 유용성, 지각된 용이성, 지각된 흥미성. 본 연구모형은 2개 대학의 대학생 254명을 대상으로 TOEIC콘텐츠를 공부하는 온/오프라인의 가상적인 스터다그룹을 구성하여 협동학습을 수행하도록 하고, 이에 대한 자료를 세 차례의 설문을 통하여 수집하여 분석하였다. 연구결과는 다차원으로 분해된 변수들 중 태도적 믿음 변수인 지각된 용이성을 제외하고 분해된 모든 변수가 사용의도에 긍정적 강한 영향을 미치고 있음을 알 수 있었고, 특히, 웹기반 협동학습지원시스템의 다양한 기능(협동학습을 통한 화상토론, 게시판활동, 오프라인 정기 모임, 동영상 동시 시청)을 통하여 팀장과 팀원들의 상호작용과 함께 사용의도에도 직접적 영향을 줄 수 있기 때문에 명시적 사회적 영향, 암시적 사회적 영향 변수는 준거집단을 통해서 웹기반 협동학습 시스템에 대한 행동의도나 인지에 영향을 줄 수 있는 중요 변수로 나타났다.

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포로히-블루머(Forouhi-Bloomer) 분산식을 이용한 유기발광물질 Alq3의 광학 상수 결정 (Determination of optical constants for organic light emitting material of Alq3 using Forouhi-Bloomer dispersion relations)

  • 정부영;우석훈;이석목;황보창권
    • 한국광학회지
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    • 제14권1호
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    • pp.1-7
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    • 2003
  • 유기발광물질 Alq$_3$ 복소굴절률을 양자역학적 흡수이론인 바탕인 포로히-블루머(Forouhi-Bloomer) 분산식[Phys. Rev. B 34. 7018(1986)]을 이용하여 1.5~6 ev의 영역에서 계산하였다. 분광광도계를 이용하여 측정한 Alq$_3$ 박막의 흡수 스펙트럼에서 흡수 피크의 위치와 폭으로부터 포로히-블루머 분산식의 변수 $A_{i}$ , B$_{i}$, $C_{i}$ 의 초기 근사값을 결정하였다. 기판으로 사용한 비정질실리카(fused silica)의 굴절률은 분광광도계로부터 측정된 투과율과 반사율 스펙트럼으로부터 셀마이어(Sellmeier)분산식을 적용하여 계산하였다. 기판의 굴절률과 분광광토계에서 측정한 Alq$_3$박막의 투과율과 반사율 스펙트럼에 포로히-블루머 분산식을 이용한 비선형 최소자승법 곡선맞춤을 하여 Alq$_3$의 복소굴절률을 계산할 수 있었다.

Optical and dielectric properties of nano BaNbO3 prepared by a combustion technique

  • Vidya, S.;Mathai, K.C.;John, Annamma;Solomon, Sam;Joy, K.;Thomas, J.K.
    • Advances in materials Research
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    • 제2권3호
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    • pp.141-153
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    • 2013
  • Nanocrystalline Barium niobate ($BaNbO_3$) has been synthesized by a novel auto-igniting combustion technique. The X-Ray diffraction studies reveals that $BaNbO_3$ posses a cubic structure with lattice constant $a=4.071{\AA}$. Phase purity and structure of the nano powder are further examined using Fourier-Transform Infrared and Raman spectroscopy. The average particle size of the as prepared nano particles from the Transmission Electron Microscopy is 20 nm. The UV-Vis absorption spectra of the samples are recorded and the calculated average optical band gap is 3.74eV. The sample is sintered at an optimized temperature of $1425^{\circ}C$ for 2h and attained nearly 98% of the theoretical density. The morphology of the sintered pellet is studied with Scanning Electron Microscopy. The dielectric constant and loss factor of a well-sintered $BaNbO_3$ at 5MHz sample is found to be 32.92 and $8.09{\times}10^{-4}$ respectively, at room temperature. The temperature coefficient of dielectric constant was $-179pp/^{\circ}C$. The high dielectric constant, low loss and negative temperature coefficient of dielectric constant makes it a potential candidate for temperature sensitive dielectric applications.

INVESTIGATION OF EQUINE HEMATOLOGICAL CONSTITUENTS IN CENTRAL TAIWAN. I. DISTRIBUTION OF THE BLOOD CELL PARAMETERS AND THE BIOCHEMICAL COMPOSITIONS OF SERUM

  • Ju, J.C.;Cheng, S.P.;Fan, Y.K.;Hsu, J.C.;Chiang, S.K.;Chen, E.V.;Chang, S.H.;Chiou, S.C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제6권1호
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    • pp.147-153
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    • 1993
  • A total of 109 heads of horses and ponies from eight horseback riding clubs nearby Central Taiwan were investigated to evaluate the blood parameters and the biochemical compositions of serum for the documentation of clinical pathological diagnosis and exercise physiology. Blood samples were collected from the jugular vein of resting horses. The sex difference in the blood traits were compared both in horses and in ponies. Results shows that total plasma proteins (PP) and hematocrit (PCV) were found higher in male horses than in females (p < 0.05). The sexual effect also exertes a significant influence on the leucocyte (WBC) count, but not on the erythrocyte (RBC) concentration. According to the differential counts of leucocytes, the number of monocytes and lymphocytes was higher in the male pony than that of in male horse. A close relationship Between the erythrocyte sedimention rate (ESR) and the other blood parameters were found especially in PCV, RBC concentration, and plasma protein level. The average ESR observed at 60 minutes were $21.80{\pm}21.87mm$, $39.50{\pm}18.90mm$ and $43.73{\pm}17.89mm$ in stallions, geldings, and mares, respectively. Most of the biochemical components of horse serum detected were distributed in normal ranges, although some of the items show a great variation in such a large sample size.

제주도입란우의 번식장해원인에 관한 연구 II. 제주도입 유우의 번식상황 조사 (A Study on the Occurences and Caused Reproductive Disorders of the Introduced Dariy Cattle in Cheju-do I. The Investigation of Reproductive Performances)

  • 김종규;양기천;강민수;김철균;박희석;김동철
    • 한국가축번식학회지
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    • 제10권1호
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    • pp.58-65
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    • 1986
  • The results from a survery on the reproduction of a, pp.oximately 500 dairy cows raised in four different farming areas including Cheju city, Jochun, Hallim and Sung-up are summarized as follows; 1. At the occurrence of first estrus, the average age of the heifers was 15.1 months (330 Kg/B.W.), and at first conception 18.0 months (354Kg/B.W.). There was no regional differences. 2. The average interval of the estrous cycle was 20.4 days. And the repetition of esturs after unsuccessful insemination occurred on an average of 1.6 times, especially 2.0 times in the herds of the Jochun district. 3. The ages at the first calving were similar to the data recorded for the domestic mainland's herds at 27.1 months. But some regional differences were recognized within the four districts: i.e. 28.6 (Cheju city), 27.4(Jochun), 27.1(Hallim) and 25.3 months (Sung-up). There was no significant differences in sex ratio of newborns at 50.4%(♂) and 49.6%(♀). 4. The intervals of esturs recurrence and the following conception after calving were 80.0 and 95.8 days respectively. In the followsing conception intervals after cavling, 90.6-97.4 days were average for the herds of Cheju city and Jochun districts, 62.4-69.7 days for those of Hallim and Sung-up districts. 5. The average gestation period was 279.8 days, and was almost identical in the four districts. 6. The calving intervals was 377.7 days in average, and it was shorter than the data recorded for the domestic mainland's herds. Also it was reduce gradually according to the calving frequency.

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실험 계획법을 이용한 점착방지막용 플라즈마 증착 공정변수의 최적화 연구 (Optimizing the Plasma Deposition Process Parameters of Antistiction Layers Using a DOE (Design of Experiment))

  • 차남구;박창화;조민수;박진구;정준호;이응숙
    • 한국재료학회지
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    • 제15권11호
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    • pp.705-710
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    • 2005
  • NIL (nanoimprint lithography) technique has demonstrated a high potential for wafer size definition of nanometer as well as micrometer size patterns. During the replication process by NIL, the stiction between the stamp and the polymer is one of major problems. This stiction problem is moi·e important in small sized patterns. An antistiction layer prevents this stiction ana insures a clean demolding process. In this paper, we were using a TCP (transfer coupled plasma) equipment and $C_4F_8$ as a precursor to make a Teflon-like antistiction layer. This antistiction layer was deposited on a 6 inch silicon wafer to have nanometer scale thicknesses. The thickness of deposited antistiction layer was measured by ellipsometry. To optimize the process factor such as table height (TH), substrate temperature (ST), working pressure (WP) and plasma power (PP), we were using a design of experimental (DOE) method. The table of full factorial arrays was set by the 4 factors and 2 levels. Using this table, experiments were organized to achieve 2 responses such as deposition rate and non-uniformity. It was investigated that the main effects and interaction effects between parameters. Deposition rate was in proportion to table height, working pressure and plasma power. Non-uniformity was in proportion to substrate temperature and working pressure. Using a response optimization, we were able to get the optimized deposition condition at desired deposition rate and an experimental deposition rate showed similar results.

Ductility demands and reduction factors for 3D steel structures with pinned and semi-rigid connections

  • Llanes-Tizoc, Mario D.;Reyes-Salazar, Alfredo;Ruiz, Sonia E.;Bojorquez, Eden;Bojorquez, Juan;Leal Graciano, Jesus M.
    • Earthquakes and Structures
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    • 제16권4호
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    • pp.469-485
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    • 2019
  • A numerical investigation regarding local (${\mu}_L$) and story (${\mu}_S$) ductility demand evaluation of steel buildings with perimeter moment resisting frames (PMRF) and interior gravity frames (IGF), is conducted in this study. The interior connections are modeled, firstly as perfectly pinned (PP), and then as semi-rigid (SR). Three models used in the SAC steel project, representing steel buildings of low-, mid-, and high-rise, are considered. The story ductility reduction factor ($R_{{\mu}S}$) as well as the ratio ($Q_{GL}$) of $R_{{\mu}S}$ to ${\mu}_L$ are calculated. ${\mu}_L$ and ${\mu}_S$, and consequently structural damage, at the PMRF are significant reduced when the usually neglected effect of SR connections is considered; average reductions larger than 40% are observed implying that the behavior of the models with SR connections is superior and that the ductility detailing of the PMRF doesn't need to be so stringent when SR connections are considered. $R_{{\mu}S}$ is approximately constant through height for low-rise buildings, but for the others it tends to increase with the story number contradicting the same proportion reduction assumed in the Equivalent Static Lateral Method (ESLM). It is implicitly assumed in IBC Code that the overall ductility reduction factor for ductile moment resisting frames is about 4; the results of this study show that this value is non-conservative for low-rise buildings but conservative for mid- and high-rise buildings implying that the ESLM fails evaluating the inelastic interstory demands. If local ductility capacity is stated as the basis for design, a value of 0.4 for $Q_{GL}$ seems to be reasonable for low- and medium-rise buildings.

Methodology for the Observations of Stellar Occultations by Small Bodies of the Solar System

  • Salazar-Manzano, Luis E.;Quintero, Edwin A.
    • Journal of Astronomy and Space Sciences
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    • 제38권1호
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    • pp.1-21
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    • 2021
  • The observation of stellar occultations constitutes one of the most important techniques for determining the dimensions and establishing the physical parameters of small Solar System bodies. The most substantial calculations are obtained from multiple observations of the same event, which turns the observation of stellar occultations into highly collaborative work and groups teams of observers through international networks. The above situation also requires the participation of both professional and amateur observers in these collaborative networks. With the aim of promoting the participation of professional and amateur groups in the collaborative observation of stellar occultations, we present the methodology developed by the Astronomical Observatory of the Technological University of Pereira (OAUTP) for the observations of occultations due small Solar System bodies. We expose the three fundamental phases of the process: the plan to make observations, the capture of the events, and the treatment of the data. We apply our methodology using a fixed station and a mobile station to observe stellar occultations due to MBAs (354) Eleonora (61) Danae (15112) Arlenewolfe (3915) Fukushima (61788) 2000 QP181 (425) Cornelia (257) Silesia (386) Siegena and (41) Daphne, and due to TNOs 1998BU48 and (529823) 2010 PP81. The positive detections for the objects (257) Silesia (386) Siegena and (41) Daphne allow us to derive lower limits in the diameter of the MBAs of 63.1 km, 166.2 km and 158.7 km and offsets in the astrometric position (Δαc cos��c, Δ��c) of 622.30 ± 0.83, 15.23 ± 9.88 mas, 586.06 ± 1.68, 43.03 ± 13.88 mas and -413.44 ± 9.42, 234.05 ± 19.12 mas, respectively.

English Predicate Inversion: Towards Data-driven Learning

  • Kim, Jong-Bok;Kim, Jin-Young
    • 영어영문학
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    • 제56권6호
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    • pp.1047-1065
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    • 2010
  • English inversion constructions are not only hard for non-native speakers to learn but also difficult to teach mainly because of their intriguing grammatical and discourse properties. This paper addresses grammatical issues in learning or teaching the so-called 'predicate inversion (PI)' construction (e.g., Equally important in terms of forest depletion is the continuous logging of the forests). In particular, we chart the grammatical (distributional, syntactic, semantic, pragmatic) properties of the PI construction, and argue for adata-driven teaching for English grammar. To depart from the arm-chaired style of grammar teaching (relying on author-made simple sentences), our teaching method introduces a datadriven teaching. With total 25 university students in a grammar-related class, students together have analyzed the British Component of the International Corpus of English (ICE-GB), containing about one million words distributed across a variety of textual categories. We have identified total 290 PI sentences (206 from spoken and 87 from written texts). The preposed syntactic categories of the PI involve five main types: AdvP, PP, VP(ed/ing), NP, AP, and so, all of which function as the complement of the copula. In terms of discourse, we have observed, supporting Birner and Ward's (1998) observation that these preposed phrases represent more familiar information than the postposed subject. The corpus examples gave us the three possible types: The preposed element is discourse-old whereas the postposed one is discourse-new as in Putting wire mesh over a few bricks is a good idea. Both preposed and postposed elements can also be discourse new as in But a fly in the ointment is inflation. These two elements can also be discourse old as in Racing with him on the near-side is Rinus. The dominant occurrence of the PI in the spoken texts also supports the view that the balance (or scene-setting) in information structure is the main trigger for the use of the PI construction. After being exposed to the real data and in-depth syntactic as well as informationstructure analysis of the PI construction, it is proved that the class students have had a farmore clear understanding of the construction in question and have realized that grammar does not mean to live on by itself but tightly interacts with other important grammatical components such as information structure. The study directs us toward both a datadriven and interactive grammar teaching.

식초절임 무의 HACCP 시스템 적용을 위한 미생물학적 위해 분석 (Microbiological Hazard Analysis for HACCP System Application to Vinegared Pickle Radishes)

  • 권상철
    • 한국식품위생안전성학회지
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    • 제28권1호
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    • pp.69-74
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    • 2013
  • 본 연구는 식초절임 무의 HACCP (Hazard Analysis Critical Control Point)시스템 구축을 위하여 생물학적 위해요소분석을 위한 목적으로 2012년 2월 1일~6월 31일까지 약 150일 동안 수행하였다. 일반적인 식초절임 무 제조업체의 제조공정을 참고로 하여 공정도를 작성하였으며, 식초절임 무의 원료 농산물(무), 용수, 첨가물과 포장재료에 입고, 보관, 정선, 세척, 표피제거, 절단, 선별, 충진, 내포장, 금속검출, 외포장, 보관 및 출하공정에 대하여 작성하였다. 원료 무의 세척 전, 세척 후의 Coliform group, Staphylococcus aureus, Salmonella spp., Bacillus cereus, Listeria Monocytogenes, E. coli O157:H7, Clostridium perfringens, Yeast 와 Mold를 측정한 결과 Bacillus cereus는 세척 전 $5.00{\times}10$ CFU/g이었으나, 세척 후 검출되지 않았으며, Yeast 와 Mold 는 세척 전 $3.80{\times}10^2$ CFU/g, 세척 후 10 CFU/g로 감소되었으며 나머지 병원성균은 검출되지 않았다. 조미액의 pH(2~5)별 미생물의 변화를 시험한 결과 모든 균이 검출되지 않은 pH 3~4를 조미액의 pH로 결정하였다. 작업장별 공중낙하균 (일반세균수, 대장균, 진균수) 시험결과 내포장실, 조미액가공실, 세척실, 보관실의 미생물수는 10 CFU/Plate, 2 CFU/Plate, 60 CFU/Plate 그리고 20 CFU/Plate 가 검출되었다. 종사자 손바닥 시험결과 일반세균수 346 $CFU/Cm^2$, 대장균군 23 $CFU/Cm^2$로 높게 나타나 개인위생관리에 대한 교육 및 훈련이 요구 되었다. 제조설비 및 기구의 표면오염도를 검사한 결과 모든 시료에서 대장균군은 검출되지 않았고, 일반세균은 PP Packing machin과 Siuping machine (PE Bulk)에서 가장 많은 $4.2{\times}10^3CFU/Cm^2$, $2.6{\times}10^3CFU/Cm^2$ 검출되었다. 위의 위해분석 결과 병원성미생물을 예방, 감소 또는 제거할 수 있는 조미액 가공 공정이 CCP-B (Biological)로 관리되어야 하고, 한계기준은 pH 3~4로 결정하였다. 따라서 전통한과생산에의 HACCP 모델 적용을 위한 미생물학적 위해도 평가에서와 같이 조미액 가공 공정의 관리기준 및 이탈시 조치방법, 검증방법, 교육 훈련과 기록관리 등 철저한 HACCP 관리계획이 필요할 것으로 생각된다.