• 대한간호
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• 제11권2호통권58호
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• pp.78-79
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• 1972

• 한국지반공학회지:지반
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• 제18권9호
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• pp.18-18
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• 2002

• 한국대기환경학회지
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• 제25권1호
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• pp.75-89
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• 2009

The purpose of this study was to identify $PM_{2.5}$ sources and to estimate their contributions to the border of Yongin-Suwon area, based on the analysis of the $PM_{2.5}$ mass concentration and the associated inorganic elements, ions and carbon components. The contribution of $PM_{2.5}$ sources were estimated by using a positive matrix factorization (PMF) model to identify air emission sources. For this study, $PM_{2.5}$ samples were collected from May, 2007 to April, 2008. The inorganic elements were analyzed by an ICP-AES. The ionic components in $PM_{2.5}$ were analyzed by an Ie. The carbon components were also analyzed by DRI/OGC analyzer. After performing PMF modeling, a total of 12 sources were identified and their contributions were quantitatively estimated. The contributions from each emission source were as follows: 11.3% from oil combustion source, 3.4% from bus/highway source, 5.8% from diesel vehicle source, 4.7% from gasoline vehicle source, 8.8% from biomass burning source, 15.1 % from secondary sulfate, 5.2% from secondary nitrate source, 13.4% from industrial related source, 4.1% from Cl-rich source, 19.6% from soil related source, 1.0% from aged sea salt, and 7.4% from coal combustion source, respectively. This study provides basic information on the major sources affecting air quality, and then it will help to effectively control $PM_{2.5}$ in this study area.

• 자원리싸이클링
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• 제29권4호
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• pp.45-50
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• 2020

전기·전자제품 생산업자와 판매업자는 자신이 배포한 장비가 속하는 등급에 해당하는 폐전기·전자제품을 직접 수거하거나 한국전자제품자원순환공제조합에 가입하여 공제조합이 대리할 의무를 이행하도록 할 수 있다. 본 연구에서는 분담금의 요율체계를 검토하고, 파악한 문제점과 이에 대한 개선방안을 제시한다. 첫째, 수집비 및 운반비에 대해 회수유형별 작업을 고려하여 표준작업 및 시간을 설정해야 한다. 둘째, 리사이클링센터의 선별방식에 차이가 있으므로, 이들 방식의 차이와 처리하는 제품군 특성을 반영하여 할당인자에 대한 표준원가를 설정해야 한다. 셋째, 방문수거비 예측모형에서 최소값이 아닌 중앙값 또는 평균값으로 결정하여 충분한 규모의 예산을 확보해야 한다. 본 연구는 공제회원이 공제조합에 납부하는 분담금의 문제점을 살펴보고 이에 대한 개선방안을 제시하였다.

• 한국심리학회지 : 문화 및 사회문제
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• 제11권1호
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• pp.157-180
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• 2005

R. Sternberg가 1977년에 처음으로 제안한 유추의 요소 이론으로부터 오늘날의 성공 지능이론에 이르기까지 그의 이론은 IQ의 대안적인 새로운 지능 이론으로서 지능의 정의 및 본질, 측정, 교육 및 산업 분야에 큰 영향을 미쳤다. 4반세기가 지난 현재 시점에서 그의 이론이 그동안 어떻게 변화되어 왔는지, 그 변화된 이론들은 지능 이론과 연구 분야에 각각 어떻게 기여했는지, 이론과 관련해 우리나라에서 어떤 연구들이 수행되었는지, 그리고 앞으로의 연구 과제가 무엇인지를 폭넓게 개관하는 일은 시의 적절하고 필요한 과제이다. 따라서 이 논문에서는 먼저 R. Sternberg의 지능 이론이 발달되어 온 과정을 크게 요소이론, 삼위일체 이론, 성공 지능이론의 세 시기로 구분하여 각 시기별로 그의 지능 이론과 연구의 특징과 의의를 살펴보고, 다음에 그의 지능 이론과 관련하여 그간에 우리나라에서 수행된 연구들을 주제별로 의의와 한계를 논의하며, 마지막으로 그의 이론 발달을 위한 몇 가지 연구 과제를 제언한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2182-2187
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• 2007

The relative contributions of phonon and electron to the thermal conductivity of silicon film with varying doping density are evaluated from the modified electron-phonon interaction model, which is applicable to the micro/nanoscale simulation of energy transport between energy carriers. The thermal conductivities of intrinsic silicon layer thicknesses from 20 nm to 500 nm are calculated and extended to the variation in n-type doping densities from 1.0 ${\times}$ $10^{18}$ to 5.0 ${\times}$ $10^{20}$ $cm^{-3}$, which agree well with the experimental data and theoretical model. From simulation results, the phonon and electron contributions to thermal conductivity are extracted. The electron contribution in the silicon is found to be not negligible above $10^{19}$ $cm^{-3}$, which can be classified as semimetal or metal by the value of its electrical resistivity at room temperature. The thermal conductivity due to electron is about 57.2% of the total thermal conductivity at doping concentration 5.0 ${\times}$ $10^{20}$ $cm^{-3}$ and silicon film thickness 100 nm.

• 한국환경과학회지
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• 제3권4호
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• pp.393-402
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• 1994

It is necessary to examine the source contributions and the relationship between a receptor and sources for the resonable controlling of air pollution level of suspended particulate matters. Therefore, in this study, profiles of sources contributing to the concentration of suspended particulate matters, were developed and CMB model was applied to obtain information of source contributions and feasibility of CMB model application. According to the propose of this study, twenty-seven chemical species such as the elements, anions, and total carbon of thirty-six PMl0 and TSP data sets sampled at the Pomch'on receptor site in Pusan for a 24-hr period from May to Aug. 1992, were analyzed and three (transportation, soil, marine) different source profiles were developed through the field measurement. Applying CMB model to transportation, soil, marine, the results of source contribution by CMB model showed that the case with TSP was more suitable for CMB model than that with PMl0. And the average contribution of transportation source to TSP and PMlo concentration at Pomch'on receptor was calculated as 90.66 ㎍/m3(64%) and 23.27 ㎍/m3(39%), resfiectively, which showed that the contribution by transportation was dominant. The validation of CMB model was performed by means of the results of contributions from marine source for the wind direction sectors.

• 한국수학사학회지
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• 제24권4호
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• pp.87-96
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• 2011

프로이덴탈은 대수적 위상수학과 기하학에 중요한 업적을 남겼으며, 수학사와 수학교육에도 크게 이바지한 수학자다. 많은 업적 중 가장 인정받는 것은 1970년대, 세계적으로 유행하던 새수학으로부터 네덜란드의 수학을 보호한 것이다. 그가 남긴 가장 큰 유산은 ICMI의 회장으로 재임하면서 현실적 수학교육의 기초를 다졌으며, 또 세계 수학교육에 영향을 끼치는 ICME 개최로 그 위상을 높인 점이다. ICMI의 회장이었던 Bass가 프로이덴탈이 회장으로 재임하였던 기간을 프로이덴탈 시대라고 명명하였으며, 많은 수학교육학자들 역시 ICMI의 역사를 프로이덴탈 이전 시대와 프로이덴탈 후기시대로 나누는데 동의할 정도로 그가 ICMI에 끼친 영향력은 대단하다. 이 논문에서는 프로이덴탈의 생애를 돌아보고 그가 ICMI를 통하여 세계수학교육에 미친 영향을 살펴보고자 한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 춘계학술대회 논문집
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• pp.123-125
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• 2010

As the exterior noise emitted by a vehicle is getting more and more attention, simulated pass-by measurements become more important. This well established method provides information about the total noise emitted by the vehicle. For a vehicle manufacturer it is not only interesting to know about the total noise but also to know how this total exterior noise is composed of different contributions, such as for example the contribution of the engine, the intake or exhaust system. Transfer path analysis (TPA) provides a separation of these contributions for each of the pass-by microphones alongside the track. Presented is a method for fast and efficient determination of the contributions of multiple sources using operational transfer path analysis (OTPA). The calculation of the transfer characteristics between the reference measurement points on the vehicle and the corresponding response points of both microphone lines are carried out while operation of the vehicle. As result of the contribution analysis from operational transfer path analysis, the characteristic noise level as function of the covered distance is displayed for all individual sound sources, thus providing in depth information for sound quality engineering.

• 한국환경과학회지
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• 제19권3호
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• pp.269-279
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• 2010

The relative contributions of physical and chemical processes to the production of ozone ($O_3$) were evaluated based on an integrated process rate (IPR) analysis using the MM5/CMAQ in a downtown (i.e., Yangsan_U) and suburban area (i.e., Ungsang) on high ozone days during spring and summer in 2006 (28 April and 8 August 2006). The IPR includes a horizontal advection (HADV) and diffusion (HDIF), a vertical advection (ZADV) and diffusion (VDlF), a dry deposition (DDEP), and a chemistry (CHEM). The VDIF in Yangsan_U was found to be the most dominant contributor (29.5% in spring and 32.1% in summer) to high $O_3$ concentrations, followed by the HADV and ZADV. In contrast, the contributions of the HADV (40.3% in spring and 32.3% in summer) in Ungsang were significantly higher than those of VDIF and ZADV. Moreover, $O_3$ production due to the chemical effect in the two areas (especially in Ungsang) during summer was found to be moderately higher than that during spring.