• 제목/요약/키워드: post-2012

검색결과 1,266건 처리시간 0.024초

The Effect of Science Writing Heuristic on Concept Formation of Light in 'Mirrors and Lenses' and Scientific Attitudes

  • Kwon, Sunggi;Lee, Su-Young;Jeong, Min-Ah
    • 한국과학교육학회지
    • /
    • 제32권6호
    • /
    • pp.1027-1038
    • /
    • 2012
  • We investigated the effect of Science Writing Heuristic (SWH) on elementary students' concept formation and their retention. Also we explored the interaction effect of those with scientific attitudes. We developed mirrors/lenses lessons incorporating SWH. An experimental group of fifth grade students (n=25) had been instructed with SWH lessons for six periods while a control group (n=25) taught according to the normal science lessons based on the Korean national curriculum using teacher's guides published by the Ministry of Education. Results of pre- and post-test of understanding the concept of mirrors and lenses showed a positive impact of SWH on both male and female students. However, the retention effect after post-test revealed that SWH only had an effect on female students' scientific attitudes. SWH, therefore, could be an effective teaching approach especially on concept formation, retention effects by fostering female students' scientific attitudes.

Analytical approximate solutions for large post-buckling response of a hygrothermal beam

  • Yu, Yongping;Sun, Youhong
    • Structural Engineering and Mechanics
    • /
    • 제43권2호
    • /
    • pp.211-223
    • /
    • 2012
  • This paper deals with large deformation post-buckling of a linear-elastic and hygrothermal beam with axially nonmovable pinned-pinned ends and subjected to a significant increase in swelling by an alternative method. Analytical approximate solutions for the geometrically nonlinear problem are presented. The solution for the limiting case of a string is also obtained. By coupling of the well-known Maclaurin series expansion and orthogonal Chebyshev polynomials, the governing differential equation with sinusoidal nonlinearity can be reduced to form a cubic-nonlinear equation, and supplementary condition with cosinoidal nonlinearity can also be simplified to be a polynomial integral equation. Analytical approximations to the resulting boundary condition problem are established by combining the Newton's method with the method of harmonic balance. Two approximate formulae for load along axis, potential strain for free hygrothermal expansion and periodic solution are established for small as well as large angle of rotation at the end of the beam. Illustrative examples are selected and compared to "reference" solution obtained by the shooting method to substantiate the accuracy and correctness of the approximate analytical approach.

Post-processing of Direct Teaching Trajectory in Industrial Robots

  • Choi, Tae-Yong;Park, Chan-Hun;Do, Hyun-Min;Chung, Kwang-Cho;Park, Dong-Il;Kyung, Jin-Ho
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • 제12권3호
    • /
    • pp.256-262
    • /
    • 2012
  • Direct teaching of the industrial robot is a novel technique to easily teach manipulators. However, teaching data by human hand cannot help having large noise errors ranging from low to high frequency. To use teaching data, post-processing to correct the teaching trajectory is required. Here, a novel shape-based trajectory correction method to rebuild teaching data with the feature information of curvature and velocity is proposed. The proposed method is tested on square and circular objects.

2년간의 추적 연구를 통한 Physical Computing 기반의 STEAM 프로그램의 효과 (Two-year Follow-Up Study on Effects of STEAM Education Program Based on Physical Computing)

  • 김석희;유헌창
    • 컴퓨터교육학회논문지
    • /
    • 제17권2호
    • /
    • pp.77-86
    • /
    • 2014
  • 국제 학업 성취도인 PISA2007, TIMSS 2011에 의하면 우리나라 학생들의 수학, 과학 학업성취도는 최상위에 해당하지만, 관련 태도가 낮다는 결과가 나왔다. 또, 사회에 만연한 이공계 기피현상, 초중고에서 점점 사라지고 있는 정보과학 교육의 현실을 반영하는 학습 경험을 제공해야 할 필요성이 제기되었다. 이러한 필요성에 의해 본 연구자는 2012년에 Physical Computing 기반의 STEAM 프로그램을 개발하고 그 효과를 연구하였다. 그 결과 과학적 문제해결력, 과학적 태도, 인성 등에서 향상되는 결과를 얻었다. 본 연구에서는 2012년 연구의 후속연구이다. STEAM 프로그램을 적용하여 향상을 가져 온 4학년 학생들이 1년 후에 STEAM 교육을 받지 않았을 때 학생들에게 어떤 변화가 생겼는가를 연구하였다. 분석 방법은 4학년 초, STEAM 교육을 받은 4학년말, STEAM 교육을 받지 않은 5학년말의 검사 결과를 비교하였다. 그 결과 과학적 탐구에 대한 태도를 제외한 모든 영역에서 STEAM 교육을 받지 않은 5학년말은 4학년 초에 비해 향상이 없는 결과를 얻었다. 이것은 STEAM 교육의 필요성에 대한 역설적인 증거라고 할 수 있다.

  • PDF

DME 예혼합 압축착화 엔진에서 다단분사를 통한 연료 성층화 (Fuel stratification by multiple injection in DME HCCI engine combustion)

  • 윤현숙;배충식
    • 한국연소학회:학술대회논문집
    • /
    • 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
    • /
    • pp.311-312
    • /
    • 2012
  • Homogeneous charge compression ignition combustion with multiple-injection strategy using dimethyl-ether was investigated in a single cylinder direct-injection compression-ignition engine. The combustion performance and exhaust emissions were tested by varying the post injection conditions. The experiments were carried out under low load and low speed conditions. By the late post injection near the top dead center, the combustion phase was retarded and lengthened, and the fuel conversion efficiencies improved without the drawbacks of exhaust emissions increment.

  • PDF

Variables that Affect the Satisfaction of Brazilian Women with External Breast Prostheses after Mastectomy

  • Borghesan, Deise Helena Pelloso;Gravena, Angela Andreia Franca;Lopes, Tiara Cristina Romeiro;Brischiliari, Sheila Cristina Rocha;Demitto, Marcela de Oliveira;Agnolo, Catia Millene Dell;Carvalho, Maria Dalva de Barros;Pelloso, Sandra Marisa
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권22호
    • /
    • pp.9631-9634
    • /
    • 2014
  • Background: : In 2012, the breast cancer estimate worldwide stood at 1.67 million new cases, these accounting for 25% of all types of cancer diagnosed in women. For 2014, 57,120 new cases are expected, with a risk estimated at 56.1 cases for every 100,000 women. The objective of this study was to analyze the satisfaction regarding the use of external breast prostheses by women undergoing mastectomy. Materials and Methods: This cross-sectional study was conducted with 76 women who used an external breast prosthesis (EBP), registered in the services of the Cuiaba Center for Comprehensive Rehabilitation, Mato Grosso, Brazil, from 2009 to 2012. Data were collected from the records of women who had requested the opening of a process of external breast prosthesis concession. Results: Satisfaction with the EBP was identified in 56.6% of the women. Those satisfied with the EBP reported that its weight was not annoying (p<0.01). Although the women felt body sensations of stitches, pains, pulling, dormancy and phantom limb, they are satisfied with the EBP. The variable related to the displacement of the breast prosthesis during activity of everyday life has demonstrated that even though the women have reported the possibility of displacements, they are satisfied with the EBP. The satisfaction with the use of external breast prosthesis did not affect the sexuality of the women with mastectomy. Conclusions: Learning the specificities of the EBP, taking into consideration the satisfaction of its use, allows the rehabilitation team, by listening to their clientele more attentively, following up this woman throughout her life journey, supporting and guiding the best way of use, with an eye to her personal, emotional and social life, as well as to her self-esteem.

동태 글로벌 CGE 모형을 활용한 정책 포트폴리오의 Post-2012 경제적 파급효과 분석 (An Economic Impact Analysis of the Post-2012 Policy Portfolio, Utilizing the Global Dynamic CGE Model)

  • 김수이;조경엽;유승직
    • 자원ㆍ환경경제연구
    • /
    • 제18권4호
    • /
    • pp.587-635
    • /
    • 2009
  • 본 연구의 목적은 Post-2012 의무부담에 대한 경제적 파급효과 분석을 위해 글로벌 동태연산기능일반균형모형(Global Dynamic Computable General Equilibrium Model : Global CGE Model)을 개발하는 것이다. 즉, 본 모형을 통해 우리나라의 의무부담 증가에 따라서 국제 배출권거래시장과 GNP, 소비, 투자, 수 출입 등 거시경제 변수들에 미치는 영향을 살펴보고자 한다. 기존 연구와는 달리 본 모형은 전 세계를 주요 경제그룹으로 나누어 분석한 글로벌모형으로서 주요 국가의 거시경제지표를 모두 반영하고 있으며, 이론적으로는 내생적 경제성장이론을 적용하고, 정책적으로는 배출권거래제도와 탄소세 등을 반영하고 있다. 특히 외생적인 기술진보를 모형에 반영하였다. 본 분석에 의하면, 온실가스 감축이 강화될수록 경제에 미치는 악영향이 커진다는 것을 알 수 있으며 거시경제지표 중에 무역수지의 감소가 가장 크게 나타나고 그 다음으로 투자 소비의 감소율이 큰 것으로 나타났다. 특히 산업별로는 에너지 의존도가 큰 에너지 다소비 업종일수록 온실가스 감축 영향이 크게 나타난다. 그리고 현재 개발도상국의 지위를 부여받고 있는 한국이 온실가스 감축 의무부담을 받으면 상대적으로 중국 등 다른 개발도상국들은 이득을 본다.

  • PDF

만성폐쇄성폐질환 환자의 폐기능 향상을 위한 호흡중재기법의 유병기간별 비교 (Comparison of Effectiveness of Breathing Intervention Program for Improvement of Pulmonary Functions according to Prevalence Period in Patients with COPD)

  • 김용남
    • The Journal of Korean Physical Therapy
    • /
    • 제24권5호
    • /
    • pp.355-361
    • /
    • 2012
  • Purpose: The purpose of this study was to evaluate the effectiveness of pulmonary rehabilitation on lung function and fatigue in persons with chronic obstructive pulmonary disease (COPD). Methods: Thirty one persons with COPD participated in this study. Four groups were allocated as follows: experimental group 1 (under 10 years of the post-disease period), control group 1 (under 10 years of the post-disease period), experimental group 2 (over 10 years of the post-disease period), and control group 2 (over 10 years of the post-disease period). Results: Forced expired volume in one second (FEV1) % pred and lactic acid showed improvement in experimental group 1 and experimental group 2 after training. Control group 1 and control group 2 did not show improvement of FEV1% pred and lactic acid after training. However, FEV1% pred and lactic acid in experimental group 1 were not significantly different, compared with the experimental group. Conclusion: Results of our study suggest that implementation of a pulmonary rehabilitation program resulted in improvement of lung function and fatigue in persons with COPD not related to the post-disease period.

작은 디바이스를 위한 원형편파안테나 설계 (Design of Circular Polarization Antenna for Small Device)

  • 김승우;강춘호
    • 전자공학회논문지SC
    • /
    • 제49권3호
    • /
    • pp.47-52
    • /
    • 2012
  • 본 논문은 Ku대역에서 동작하는 레이더용 원형편파안테나에 대한 설계 및 실험에 관한 것으로 선형안테나를 이용하여 원형편파안테나를 만들기 위해 Post를 이용함으로 안테나의 구조적 크기를 줄일 수 있었다. 원형편파 안테나의 축비 Bandwidth을 넓히기 위해 3개의 Post을 사용하였으며, 축비 최적화를 위해 Post사이 거리와 길이를 적절하게 선정하여 설계하였다. 또한 축비 최적화를 위해 반응표면법을 이용하여 최적화를 하였으며, 구현된 안테나는 12.7%의 Impedance Bandwidth와 설계 대역 내에서 2dB 이하의 축비 특성 및 7.8dBi 이상의 이득을 확인할 수 있었다.

A New Insight into the Role of Calpains in Post-mortem Meat Tenderization in Domestic Animals: A review

  • Lian, Ting;Wang, Linjie;Liu, Yiping
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제26권3호
    • /
    • pp.443-454
    • /
    • 2013
  • Tenderness is the most important meat quality trait, which is determined by intracellular environment and extracellular matrix. Particularly, specific protein degradation and protein modification can disrupt the architecture and integrity of muscle cells so that improves the meat tenderness. Endogenous proteolytic systems are responsible for modifying proteinases as well as the meat tenderization. Abundant evidence has testified that calpains (CAPNs) including calpain I (CAPN1) and calpastatin (CAST) have the closest relationship with tenderness in livestock. They are involved in a wide range of physiological processes including muscle growth and differentiation, pathological conditions and post-mortem meat aging. Whereas, Calpain3 (CAPN3) has been established as an important activating enzyme specifically expressed in livestock's skeletal muscle, but its role in domestic animals meat tenderization remains controversial. In this review, we summarize the role of CAPN1, calpain II (CAPN2) and CAST in post-mortem meat tenderization, and analyse the relationship between CAPN3 and tenderness in domestic animals. Besides, the possible mechanism affecting post-mortem meat aging and improving meat tenderization, and current possible causes responsible for divergence (whether CAPN3 contributes to animal meat tenderization or not) are inferred. Only the possible mechanism of CAPN3 in meat tenderization has been confirmed, while its exact role still needs to be studied further.