• 제목/요약/키워드: Secondary Effect

검색결과 2,537건 처리시간 0.034초

중등학생의 특수상대론 학습에서 VR과 사건도표를 이용한 수업방법의 제안 (A Proposal of a Teaching Method using Virtual Reality and Event-Diagram for Secondary Student's Understanding of Basic Concepts in Special Relativity)

  • 김재권;김영민
    • 과학교육연구지
    • /
    • 제35권2호
    • /
    • pp.283-294
    • /
    • 2011
  • 이 연구는 개정된 물리교과서에 포함된 현대물리학 소재인 특수 상대성 이론에 대해 고등학생의 인지 수준을 고려하고 학습자의 주도적 수업참여를 구현하기 위하여 '가상현실'과 '사건도표' 활동이 포함된 수업방법을 고안하여 그 효과를 정량적이고 정성적으로 분석하는 데 목적이 있다. 특수상대론 개념 학습 프로그램을 통한 수업과 전통적 수업은 선택 후 설명식 문항의 전반적인 성취도에서 유의미한 차이를 나타내지 않았다. 프로그램 수업을 이수한 학생은 복합 개념 형 문항의 성취도는 유의미하게 높게 나타났다. 특수 상대론적 역설문제에서는 프로그램 수업집단은 전통적 수업집단보다 통계적으로 유의미하게 높은 성취도를 나타내었다. 프로그램 수업집단 학생들은 역설문제 해결과정에서 특수 상대론적 현상을 좌표계의 틀 위에서 객관적으로 설명하는 좌표계 의존 형 문제 해결방식의 특성을 나타내었다. 전통적 수업집단의 학생들은 특수 상대론적 현상을 불완전하거나 잘못된 좌표계 개념으로 설명하였고 사건의 순서를 관찰자의 직관에 의존하여 판단하는 관찰자 의존형 문제 해결방식을 나타내었다. 특수 상대론적 효과가 시각화된 영상을 보고 사건도표라는 가상의 시공간을 노트에 그려보고 생각하는 활동은 학생들에게 도약판을 만들어 주는 하나의 방법으로 제안한다.

  • PDF

Nursery depopulation 기법에 의한 돼지 호흡기질병 상재돈군의 호흡기 병인체 전파방지에 관한 연구 (Elimination of respiratory pathogens in endemically infected swine herds by nursery depopulation)

  • 김봉환;주한수
    • 대한수의학회지
    • /
    • 제37권4호
    • /
    • pp.755-763
    • /
    • 1997
  • Recently new technologies for the establishment of high health herds are becoming efficient tools in the control of PRRS virus and secondary infections. Medicated early weaning(MEW) and nursery depopulation(ND) have shown to be one of the most successful procedures in the eradication and control of pathogens. Indirect evidence of the role of PRRSV in precipitating secondary infection comes from successful improvement in growth and in decreasing mortality on farms that have eliminated PRRSV through ND. Hence the present experiments were conducted in an effort to compare ND with MEW procedures as a means of eliminating PRRSV controlling secondary pathogens and improving performance of pigs in endemically infected swine herds. Following MEW and ND procedures practiced in the farms, some benefits obtained were as follows: 1. A decrease in PRRSV circulation in the nursery, but no entire elimination. 2. Decrease in the frequency of secondary bacteria and in the use of antibiotics. 3. Mycoplasma hyopneumoniae infection was prevented during the nursery stage. 4. ND protocol had a lower cost and management changes than MEW techniques. 5. Nursery performance was improved after the depopulation, cleaning and disinfection procedures, even though PRRSV still being cycled in the old nursery rooms. These studies revealed that the MEW and ND protocols are not always successful for PRRS virus elimination but it's great effect on control of secondary pathogens and improvement of performance make MEW and ND an efficient tools for the establishment of healthier and more efficient herds.

  • PDF

교육만족도와 관계적 지원이 한국 고등학교학생들의 자기효능감과 기업가정신에 미치는 영향에 관한 연구 (How Educational Satisfaction and Relational Support Affect Self-Efficacy and Entrepreneurship of Korean Secondary School Students)

  • 양준환
    • 한국산학기술학회논문지
    • /
    • 제18권11호
    • /
    • pp.573-583
    • /
    • 2017
  • 기업가정신은 국가경제성장과 사회의 부를 창출해 주는 혁신의 원천으로서 많은 국가에서 각광받아왔다. 미래사회의 잠재 혁신가이며 기업가인 청소년들의 기업가정신 함양은 무엇보다 중요하다 하겠다. 이에 따라 중 고등학생들의 기업가정신 함양을 위한 정규교육의 필요성이 날로 증대되고 있는 실정이다. 본 연구의 목적은 (사)한국벤처기업가협회에서 주관한 기업가정신교육프로그램에 참가했던 전국의 고등학생들을 대상으로 기업가정신 교육만족도 및 가족 친지로부터의 관계적 지원이 청소년들의 자기효능감과 기업가정신 함양에 미치는 효과를 실증 검증하는 것이다. 검증결과 교육만족도와 관계적 지원 모두 고등학생들의 자기효능감에 유의한 정(+)의 영향을 미치고 있음을 알 수 있었다. 또한 청소년 고등학생들의 자기 효능감은 기업가정신 함양과 유의한 정(+)의 관계에 있음을 알 수 있었다. 자기효능감은 교육만족과 관계적 지원이 각각 기업가정신함양에 영향을 미치는데 있어 부분매개효과를 갖는 것으로 나타났다. 청소년들을 미래 경제성장 동력원으로 육성하기 위해서는 학교에서의 교육뿐만 아니라 부모, 친지 등으로부터 도전에 대한 격려, 성공한 기업가를 통한 역할 모델이 매우 중요할 수 있음을 제시하였다.

이차성 삼차신경통에서 경피적 고주파 삼차신경절제술에 의한 동통조절 효과 (Effect of Pain Control with Percutaneous Radiofrequency Rhizotomy in Secondary Trigeminal Neuralgia)

  • 강승범;손병철;김문찬;강준기
    • Journal of Korean Neurosurgical Society
    • /
    • 제29권1호
    • /
    • pp.66-71
    • /
    • 2000
  • Objective : There are many treatment modalitis in management of idiopathic trigeminal neuralgia. In the secondary trigeminal neuralgia, there has been only sporadic reports of the etiology. Authors report the treatment result of secondary trigeminal neuralgia with percutaneous radiofrequency rhizotomy. Methods : During last ten years, 129 trigeminal neuralgias were treated by percutaneous radiofrequency(RF) rhizotomy by authors. Among them, nine patients were secondary trigeminal neuralgias. These patients refused treatment for the primary cause and only wanted pain control. The offending lesions were three arachnoid cysts, six tumors. The mean age was 47.8 years and the mean duration of follow-up was 6.2 years. The right V2,3 distribution was most prevalent area of pain. Authors used the conventional Hartel's anterior approach and straight electrode for RF lesion generation. Result : The early result was satisfactory. Eight of nine patients became free of pain and one patient needed minimal dose of carbamazepine. The overall pain control was 100%. There was no mortality or morbidity for initial RF rhizotomy. During follow-up, four patients showed recurrence of pain(44%). Among these, two underwent repeated RF rhizotomy and became free of pain. The other two were controlled with medical management. Conclusion : These results indicate that the percutaneous RF rhizotomy is effective means of pain control. Overall recurrence was somewhat higher than that of idiopathic trigeminal neuralgia. Even with recurrence, however, repeated RF rhizotomy seems to be effective method of control of pain in these cases.

  • PDF

리튬-황 이차전지 양극 조성 성분의 비율이 전지 성능에 미치는 영향에 관한 연구 (Effect of Cathodes Prepared with Different Compositions on the Performace of Li-Sulfur Secondary Battery)

  • 최윤정;주재백;조원일
    • 전기화학회지
    • /
    • 제21권1호
    • /
    • pp.6-11
    • /
    • 2018
  • 다양한 전자제품에서 높은 성능의 이차 전지가 요구됨에 따라 안전하고 친환경적이며 경제적인 이차 전지 전극 재료의 개발을 필요로 하고 있다. 리튬-황 배터리는 높은 이론용량과 에너지밀도, 그리고 친환경적인 물질이라는 점에서 차세대 이차전지로써 주목받고 있지만, 폴리설파이드의 용출로 인한 전지 용량감소현상이 일어나고, 황의 부도체 특성으로 인해 아직 상용화 단계에 미치지 못하고 있다. 본 연구에서는 보다 향상된 이차 전지 전극 재료로서 다른 양극 물질들에 비해 에너지 밀도가 높은 황을 양극재로 사용하여 전지를 만들고 이 때 양극 활물질의 구성요소인 황, 도전재, 바인더의 비율을 다양하게 변화하면서 양극을 제조하고 여러 전기화학적 평가를 거쳐 가장 좋은 전지 성능을 낼 수 있는 구성성분 비율을 모색하고자 하였다.

뇌졸중 이차예방 교육프로그램이 급성기 허혈성 뇌졸중환자의 자가간호수행에 미치는 효과 (An Effect of the Secondary Stroke Prevention Education Program on Self-care of Acute Ischemic Stroke Patients)

  • 강선미;윤은자
    • 성인간호학회지
    • /
    • 제17권4호
    • /
    • pp.646-655
    • /
    • 2005
  • Purpose: This study was conducted to examine the effects of the secondary stroke prevention education program to inhibit the recurrence of the acute ischemic stroke patients, and to maintain and promote knowledge about stroke, self-efficacy and self-care. Method: This study was designed to take a quasi-experimental pre- and post-test with the nonequivalent control group. The experimental group consists of 20 patients and control group consists of 20 patients. The experimental group was applied the secondary stroke prevention education program. In order to verify the effects of the secondary stroke prevention education program, knowledge about stroke, self-efficacy and self-care scale were measured before the intervention and 4 weeks, 12 weeks after discharge. The tools for measuring knowledge about stroke, self-efficacy and self-care are developed by the researcher. The data was analyzed by SPSS win 10.0 program using $x^2-test$, Fisher's Exact Test, t-test, Kolmogorov-Smirnov Z, and Repeated Measures ANOVA. Result: There was a statistically significant difference in knowledge about stroke (F=4.021, p=.026), self-efficacy(F=6.096, p=.018), and self-care(F=8.026, p=.007) between the experimental and the control group after intervention. Conclusion: It is considered that the program can be used as an effective nursing intervention in clinical practice.

  • PDF

이차유동의 방향이 막냉각 효율에 미치는 영향 (Effect of Secondary Flow Direction on Film Cooling Effectiveness)

  • 박세진;최석민;손호성;정희윤;조형희
    • 대한기계학회논문집B
    • /
    • 제37권7호
    • /
    • pp.655-663
    • /
    • 2013
  • 막냉각에 관한 많은 연구들은 주유동과 이차유로가 평행한 형태로 연구가 이루어졌다. 하지만 실제 터빈 블레이드에서 이차유로의 방향은 일반적으로 주유동의 방향에 수직한 형태이다. 그래서 본 연구에서는 이차유동의 방향이 이중분사 막냉각의 효율에 미치는 영향을 수치해석을 통해 알아보고자 한다. 분사율은 1, 2이고 횡방향 분사각은 $22.5^{\circ}$이다. 분사율이 1일 때 평행 형상에서는 안티키드니 와류가 잘 형성되어 막냉각 효율이 수직 형상의 경우보다 더 높다. 반면에 분사율이 2일 때 수직 형상의 막냉각 효율은 평행 형상보다 향상되었다. 많은 유량의 제트가 서로 반대 방향으로 분사되기 때문에 두 형상 모두 막냉각 효율이 높게 나타난다. 하지만 안티키드니 와류의 영향은 다른 분사율보다 상대적으로 작다.

침구요법(鍼灸療法)에 의한 발모관련 인자들의 발현에 대한 실험적 연구 (Experimental Studies on the Expression of Hair Growth Related Factors after Acupuncture & Moxibustion Therapy)

  • 김호일;김정무;이창현
    • 동의생리병리학회지
    • /
    • 제25권4호
    • /
    • pp.674-682
    • /
    • 2011
  • The present study was undertaken to investigate the effect of acupuncture & moxibustion therapy on the hair follicle growth of skin 5 days and 10 days by macroscopic, microscopic and immunohistochemical methods. The results were as follows : Macroscopic hair follicle growth of plum-blossom needle treated group and strong moxibustion treated group was more increase than that of control group. Microscopic hair follicle growth of plum-blossom needle treated group and strong moxibustion treated group was hair growing cycle, anagen phase VI and that of control group and weak moxibustion treated group was hair growing cycle, anagen phase IV. Immunohistochemical observations on the expression of various growth factors, enzyme and receptor in hair follicle cycle after local treatment of acupuncture & moxibustion therapy are as follows: Expression of fibroblast growth factor was more intense in epidermis in plum-blossom needle treated group, epidermis and secondary hair germ cells in strong moxibustion treated group than control group. Expression of epidermal growth factor was more intense in epidermis in all experimental groups, and secondary hair germ cells in moxibustion treated group than control group. Expression of c-kit receptor was more intense in epidermis, secondary hair germ cells, outer root sheath in all experimental groups than control group. Expression of protein kinase C-${\alpha}$ was more intense in epidermis, secondary hair germ cells, outer root sheath in all experimental groups than control group. Expression of vascular endothelial growth factor was more intense in epidermis, bulge, secondary hair germ cells, outer root sheath in plum-blossom needle treated group and strong moxibustion treated group than control group. We concluded that acupuncture & moxibustion therapy related to the expression of various growth factors, enzymes and receptor on the hair growth cycle for hair growth.

A Review on Venom Enzymes Neutralizing Ability of Secondary Metabolites from Medicinal Plants

  • Singh, Pushpendra;Yasir, Mohammad;Hazarika, Risha;Sugunan, Sunisha;Shrivastava, Rahul
    • 대한약침학회지
    • /
    • 제20권3호
    • /
    • pp.173-178
    • /
    • 2017
  • Objectives: Medicinal plants are vital sources of bioactive compounds that are useful for the treatment of patients with snake bites or are indirectly applicable for boosting the effects of conventional serum therapy. These plants are being used traditionally by local healers and tribes for the treatment of patients with snake bites and therefore can be used as an alternative against snake envenomation. Scientifically, using the secondary metabolites of plants to neutralize venom enzymes has an extra benefit of being based on traditional knowledge; also, the use of such metabolites for the treatment of patients with snake bites is cheaper and the treatment can be started sooner. Methods: All the available information on various secondary metabolites exhibiting venom neutralizing ability were collected via electronic search (using Google books, Pubmed, SciFinder, Scirus, Google Scholar, and Web of Science) and articles of peer-reviewed journals. Results:Recent interest in different plant has focused on isolating and identifying of different phytoconstituents that exhibit Phospholipase A2 activity and other venom enzyme neutralizing ability. In this support convincing evidence in experimental animal models are available. Conclusion: Secondary metabolites are naturally present, have no side effect, are stable for a long time, can be easily stored, and can neutralize a wide range of snake enzymes, such as phospholipase A2, hyaluronidase, protease, L-amino acid oxidase, 5'nucleotidase, etc. The current review presents a compilation of important plant secondary metabolites that are effective against snake venom due to enzyme neutralization.

Effect of Particle Size on the Dielectric and Piezoelectric Properties of 0.95(K0.5Na0.5)NbO3-0.05BaTiO3 Lead-free Piezoelectric Ceramics

  • Bae, Seon-Gi;Shin, Hyea-Gyiung;Chung, Kwang-Hyun;Yoo, Ju-Hyun;Im, In-Ho
    • Transactions on Electrical and Electronic Materials
    • /
    • 제16권4호
    • /
    • pp.179-182
    • /
    • 2015
  • The particle sizes of 0.95(K0.5Na0.5)NbO3-0.05BaTiO3 powder were controlled by secondary milling time after calcination. The average particle sizes, Dmean, of 0.95(K0.5Na0.5)NbO3-0.05BaTiO3 powders were critically changed from 14.31 μm to 0.91 μm by secondary milling time. The dielectric and piezoelectric properties of 0.95(K0.5Na0.5)NbO3-0.05BaTiO3 ceramics depended on the particle sizes of powders after calcination and the secondary milling process. As secondary milling times after calcination were increased to more than 48 hr, the dielectric and piezoelectric properties of 0.95(K0.5Na0.5)NbO3-0.05BaTiO3 ceramics were deteriorated.