• 제목/요약/키워드: theoretical models

검색결과 1,548건 처리시간 0.026초

가족 적응력과 가족기능과의 관계 : Olson의 순환모델의 곡선성과 Beavers의 체계모 델의 선형성 (The Comparison of Olson's Circumplex Model and the Beavers' Systems Model in terms of the Relationship between Family Adaptability and Family Function)

  • 장진경
    • 가정과삶의질연구
    • /
    • 제13권4호
    • /
    • pp.1-14
    • /
    • 1995
  • Various theoretical models have developed io both a family research area and family therapy field on he basis of several family theories and social theories in order to understand the family life and its function. These theoretical models have give rise to provide not only a framework for family therapy bt also opportunities for the development of family studies. Regardless of the devotion of these theoretical models to a family therapy however some family therapy professions have suggested the disvergence between these models and practice because the models tend to confuse therapists in their actual practices Other family therapists on the other hand have claimed the convergence between these models and practice. One of the reasons for the issues of convergence and disvergence in the family therapy study would be that various theoretical models have different sometimes contradicatable definitions and explanations for same concept. Therefore the purpose of this paper is to investigate the extent of similarities and differences among these theoretical models of practice in a way of examining family models to compare Olson's circumplex model to the Beavers systems model. Both models were based on the general systems theory. This paper consists of the explanation of Olson's circumplex model and Beavers systems model in general respectively. Then it will investigate similarities and differences between these two models in terms of the relationship between family functioning and family adaptability.

  • PDF

Study on Theoretical Models of Regional Humanity Lung Cancer Hazards Assessment

  • Zhang, Chuan;Gao, Xing
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권5호
    • /
    • pp.1759-1764
    • /
    • 2015
  • Purpose: To establish the concept of lung cancer hazard assessment theoretical models, evaluating the degree of lung cancer risk of Beijing for regional population lung cancer hazard assessment to provide a basis for technical support. Materials and Methods: ISO standards were used to classify stratified analysis for the entire population, life cycle, processes and socioeconomic management. Associated risk factors were evaluated as lung cancer hazard risk assessment first class indicators. Study design: Using the above materials, indicators were given the weight coefficients, building lung cancer risk assessment theoretical models. Regional data for Beijing were entered into the theoretical model to calculate the parameters of each indicator and evaluate the degree of local lung cancer risk. Results: Adopting the concept of lung cancer hazard assessment and theoretical models for regional populations, we established a lung cancer hazard risk assessment system, including 2 first indicators, 8 secondary indicators and 18 third indicators. All indicators were given weight coefficients and used as information sources. Score of hazard for lung cancer was 84.4 in Beijing. Conclusions: Comprehensively and systematically building a lung cancer risk assessment theoretical model for regional populations in conceivable, evaluating the degree of lung cancer risk of Beijing, providing technical support and scientific basis for interventions for prevention.

Vortex-induced oscillations of bridges: theoretical linkages between sectional model tests and full bridge responses

  • Zhang, Zhitian;Ge, Yaojun;Chen, Zhengqing
    • Wind and Structures
    • /
    • 제19권3호
    • /
    • pp.233-247
    • /
    • 2014
  • Vortex-induced oscillation is a type of aeroelastic phenomenon, to which extended structures such as long-span bridges are most susceptible. The vortex-induced vibration (VIV) behaviors of a concerned bridge were investigated conventionally in virtue of wind tunnel tests on string-mounted sectional models. This necessitates the building of a linkage between the response of the sectional model and that of the prototype structure. Although many released literatures have related to this issue and provided suggestions, there is a lack of consistency among them. In this study, some theoretical models describing the vortex-induced structural motion, including the linear empirical model, the nonlinear empirical model and the modified (or generalized) nonlinear empirical model, are firstly reviewed. Then, the concept of equivalent mass density is introduced based on the principle that an equal input of energy should result in identical structural amplitudes. Based on these, the theoretical linkages between the amplitude of a section model and that corresponding to the prototype bridge are discussed with different analytical models. Theoretical derivation indicates that such connections are dependent mainly on two factors, one is the presupposed shape of deformation, and the other is the theoretical VIV model employed. The theoretical analysis in this study shows that, in comparison to the nonlinear empirical models, the linear one can result in obvious larger estimations of the full bridges' responses, especially in cases of cable-stayed bridges.

등가 드로우비드 이론 모델 검증 (Verification of Theoretical Model for Equivalent Drawbend)

  • 문성준;금영탁
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2008년도 추계학술대회 논문집
    • /
    • pp.367-369
    • /
    • 2008
  • A theoretical model of equivalent drawbead for sheet metal forming analysis is experimentally verified in this paper. After the theoretical drawbead models improved a material description for the accurate calculation of drawbead forces are briefly introduced, they are verified by showing the good agreement of their drawbead forces with experimental measurements. Furthermore, the excellence of theoretical models is demonstrated by the comparison with those of commercial codes.

  • PDF

인장과 휨변형하에서 목재의 응력이완 및 이론모형 (Stress Relaxation of Wood and Theoretical Models under Tensile and Bending Strain)

  • 장상식;강춘원
    • Journal of the Korean Wood Science and Technology
    • /
    • 제26권4호
    • /
    • pp.13-19
    • /
    • 1998
  • Stress relaxation tests have been performed under five different tensile strain levels and five different bending strain levels. Three different theoretical models have been developed based on four-element Burger's model, viscoelastic theory and viscous-viscoelastic theory. Experimental data were used to obtain parameters of the models and to verify accuracy of the models. Among the three theoretical models developed in this study, three-integral model (Model 3) based on viscous-viscoelastic theory showed the most exact estimations of stress relaxation under both tensile and bending strains and their correlation coefficients were greater than 0.99 for all the strain levels. Model 1 showed little initial stress relaxation. Model 2 showed excessive initial relaxation and, then, no relaxation after about 20 minute of strain application. Stress retention under strain decreased as strain increased, which means increased stress relaxation as strain increases. When the strain level was less than proportional limit, the effect of strain level on stress relaxation was not clearly shown. However, this effect was increased as strain level increased when strain level was greater than proportional limit.

  • PDF

전완의 등척성 수축시 최대근지구력시간을 예측하기 위한 동적근피로모델의 평가 (Evaluation of dynamic muscle fatigue model to predict maximum endurance time during forearm isometric contraction)

  • 이기영
    • 한국정보전자통신기술학회논문지
    • /
    • 제15권6호
    • /
    • pp.433-439
    • /
    • 2022
  • 최대근지구력시간(MET, maximum endurance time)을 예측하기 위한 근피로모델은 실험적으로 측정한 MET를 이용하여 구축한 실증적 모델과 생리학적 과정을 수학적으로 표현한 이론적 모델로 나뉜다. 본 연구에서는 전완의 등척성 수축시 MET을 예측하기 위한 이론적 모델인 동적 근피로모델의 예측성 평가를 위하여 실증적 모델과 비교 및 평가하고자 한다. 실험에 참여한 피검자는 40명(남성 20, 여성 20)이며 실증적 모델인 지수모델과 거듭제곱모델 및 이론적 모델인 동적 근피로모델을 이용하여 비교하였다. 평가를 위하여 평균절대치편차(MAD, mean absolute deviation), 상관계수 및 급내상관계수를 구한 결과 동적 근피로모델과 실증적 모델들 사이에 MAD는 3.5%p 이하였으며, 상관계수는 0.93, 급내상관계수는 0.87 이상으로 전완의 등척성 수축시 MET을 예측하기 위한 이론적 모델인 동적 근피로모델이 적합함을 확인하였다.

IPTV서비스 수용의 영향요인에 관한 실증적 연구 (An Empirical Study on the Influencing Factors of IPTV Service Adoption)

  • 이왕록
    • 디지털산업정보학회논문지
    • /
    • 제5권4호
    • /
    • pp.199-211
    • /
    • 2009
  • The purpose of this study is to elicit influential factors on accepting IPTV services and define the casual relationship between the factors, and "user satisfaction", "re-use intention", "stranger recommendation intention", in an attempt to provide useful guidelines to IPTV carriers, contents providers and equipment makers for their forming IPTV service models and marketing strategies. For this end, the theoretical background of this study has been brought from relevant literature, and theoretical study models have been established by logical reasoning of the interrelation among diverse components. Then, the established models have been analyzed by using statistical packages "SPSS(12.0), LISREL(8.72)". Finally theoretical and practical significance and future study direction have been suggested. To make sure of effective validity of IPTV service adoption models above, empirical studies should be made continuously. And then vertical and horizontal studies at a specific point would show ever-changing causal relationship, helping to promote financial outcome of relevant companies and organizations.

Uncertainty Quantification of the Experimental Spectroscopic Factor from Transfer Reaction Models

  • Song, Young-Ho;Kim, Youngman
    • Journal of the Korean Physical Society
    • /
    • 제73권9호
    • /
    • pp.1247-1254
    • /
    • 2018
  • We study the uncertainty stemming from different theoretical models in the spectroscopic factors extracted from experiments. We use three theoretical approaches, the distorted wave Born approximation (DWBA), the adiabatic distorted wave approximation (ADWA) and the continuum discretized coupled-channels method (CDCC), and analyze the $^{12}C(d,p)^{13}C$, $^{14}C(d,p)^{15}C$ reactions. We find that the uncertainty associated with the adopted theoretical models is less than 20%. We also investigate the contribution from the remnant term and observe that it gives less than 10% uncertainty. We finally make an attempt to explain the discrepancy in the spectroscopic factors of $^{17}C(\frac{3}{2}^+)$ between the ones extracted from experiments and from shell model calculations by analyzing the $^{16}C(d,p)^{17}C$ reaction.

음향자원조사를 위한 동물플랑크톤 요각류의 음향산란이론모델의 검토 (Examination of Theoretical Acoustic Scattering Models for Copepods in an Acoustical Zooplankton Biomass Survey)

  • 황보규;신현옥;이대재;이유원
    • 한국수산과학회지
    • /
    • 제43권4호
    • /
    • pp.380-385
    • /
    • 2010
  • Several theoretical acoustic scattering models were applied to estimate the target strength (TS) for assessing the biomass of zooplankton, to overcome the difficulty of direct measurements. Acoustical scattering characteristics of copepods were estimated using three theoretical models, and the application of the models was evaluated for four frequencies of a scientific echo sounder. The scattering directivity by the body shapes of copepods at 200 kHz and 420 kHz was significantly affected by TS patterns. Averaged TS, however, were similar at higher frequencies. Consequently, a low frequency model, such as a truncated fluid sphere model, provides a good acoustical biomass estimation. The regressions of TS and 30 logL were < $TS_{200\;kHz}$ >= 30logL-118.4 ($R^2=0.716$) and < $TS_{420 kHz}$ > =30 logL-108.8 ($R^2=0.758$), respectively.

일 뇌졸중 이차예방프로그램 논문의 분석 및 평가 (Analysis and Evaluation of a Nursing Research Paper on Secondary Prevention Program for Stroke)

  • 서은희;박선일
    • 한국농촌간호학회지
    • /
    • 제5권1호
    • /
    • pp.16-24
    • /
    • 2010
  • Nursing theory is used to explain the goals and functions of nursing and improve practical affairs by providing information and knowledge about the principles which become the foundation of nursing practical affairs. Theoretical analytical compliance with C-T-E (Conceptual-Theoretical-Empirical) structures by Fawcett (1999) whose evaluation method illustrates the relationship of conceptual models, theory, research and structure. The evaluation allows the nurse to visualize the connection, evaluate research, and reduce errors in research. Consequently present doctorate dissertations in nursing science are theoretical propriety, connection in the structure of concepts, theory, research methods, and evaluation to reduce errors in future research plans and division of theoretical development process. So the following verifies logicality, propriety, and reliability which must apply to research in various different fields.