• Title/Summary/Keyword: consistency of responses

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On the use of alternative water use efficiency parameters in dryland ecosystems: a review

  • Kang, Wenping;Kang, Sinkyu
    • Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.246-253
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    • 2019
  • Background: Water use efficiency (WUE) is an indicator of the trade-off between carbon uptake and water loss to the atmosphere at the plant or ecosystem level. Understanding temporal dynamics and the response of WUE to climatic variability is an essential part of land degradation assessments in water-limited dryland regions. Alternative definitions of and/or alternative methodologies used to measure WUE, however, have hampered intercomparisons among previous studies of different biomes and regions. The present study aims to clarify semantic differences among WUE parameters applied in previous studies and summarize these parameters in terms of their definition and methodology. Additionally, the consistency of the responses of alternative WUE parameters to interannual changes in moisture levels in Northeast Asia dryland regions (NADRs) was tested. Results: The literature review identified more than five different WUE parameters defined at leaf and ecosystem levels and indicates that major conclusions regarding the WUE response to climatic variability were partly inconsistent depending on the parameters used. Our demonstration of WUE in NADR again confirmed regional inconsistencies and further showed that inconsistencies were more distinct in hyper- and semi-arid climates than in arid climates, which might reflect the different relative roles of physical and biological processes in the coupled carbon-water process. Conclusions: The responses of alternative WUE parameters to drying and wetting may be different in different regions, and regionally different response seems to be related to aridity, which determines vegetation coverage.

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

  • Zhang, Zhitian;Ge, Yaojun;Chen, Zhengqing
    • Wind and Structures
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    • v.19 no.3
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    • pp.233-247
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    • 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.

Effect of nano glass cenosphere filler on hybrid composite eigenfrequency responses - An FEM approach and experimental verification

  • Pandey, Harsh Kumar;Hirwani, Chetan Kumar;Sharma, Nitin;Katariya, Pankaj V.;Dewangan, Hukum Chand;Panda, Subrata Kumar
    • Advances in nano research
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    • v.7 no.6
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    • pp.419-429
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    • 2019
  • The effect of an increasing percentage of nanofiller (glass cenosphere) with Glass/Epoxy hybrid composite curved panels modeled mathematically using the multiscale concept and subsequent numerical eigenvalues of different geometrical configurations (cylindrical, spherical, elliptical, hyperboloid and flat) predicted in this research article. The numerical model of Glass/Epoxy/Cenosphere is derived using the higher-order polynomial type of kinematic theory in association with isoparametric finite element technique. The multiscale mathematical model utilized for the customized computer code for the evaluation of the frequency data. The numerical model validation and consistency verified with experimental frequency data and convergence test including the experimental elastic properties. The experimental frequencies of the multiscale nano filler-reinforced composite are recorded through the impact hammer frequency test rig including CDAQ-9178 (National Instruments) and LABVIEW virtual programming. Finally, the nano cenosphere filler percentage and different design associated geometrical parameters on the natural frequency data of hybrid composite structural configurations are illustrated through a series of numerical examples.

A similarity solution for undrained expansion of a cylindrical cavity in K0-consolidated anisotropic soils

  • Wang, You;Lin, Lin;Li, Jingpei
    • Geomechanics and Engineering
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    • v.25 no.4
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    • pp.303-315
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    • 2021
  • A rigorous and generic similarity solution is developed for assessment of the undrained expansion responses of a cylindrical cavity expansion in K0-consolidated anisotropic soils. A K0-consolidated anisotropic modified Cam-clay (K0-AMCC) model that can represent the initial stress anisotropy and the effects of stress-induced anisotropy is used to model the soil behaviors during cavity expansion. All the seven basic unknowns, the three stress components, the pore water pressure, the particle velocity, the specific volume and the hardening parameter, are reduced to the functions of a dimensionless radial coordinate and are taken as coupled variables to formulate the problem. The governing equations are formulated by making use of the equilibrium equation, the constitutive equation, the consistency condition, the continuity condition and the undrained condition, which are then solved as an initial value problem. The proposed rigorous similarity solution is compared with some well-documented rigorous solutions to validate the solution and to highlight the special expansion responses in anisotropic soils. The results reveal that the present solution can yield more predictions for cavity expansion problems in soils with initial anisotropic stresses.

Consistency of ANS Responses Induced by Emotions and Emotion-Specific ANS Responses (정서에 의해 유발된 자율신경계 반응의 일관성 및 정서.특정적 자율 신경계 반응 패턴 확인)

  • 이경화;장은혜;석지아;손진훈;방석원;김경환;이미희
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2001.11a
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    • pp.104-111
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    • 2001
  • 정서와 생리반응 (자율신경계 반응) 간의 관계에 관하여 성인을 대상으로 최근가지 많은 연구가 행해져 왔다. 본 연구에서는 동일한 실험참여자를 대상으로 일정 기간 동안 여러 회의 반복실험을 통해 정서(기쁨, 슬픔, 분노, 공포, 혐오)에 따른 자율신경계의 반응의 일관성과 정서별 자율신경계 반응 패턴을 규명하고자 하였다. 본 실험에 앞서 저서를 유발하기 우한 도구인 정서유발자극세트와 정서에 대한 심리반응을 평가하기 위한 정서평가척도가 제작되었다. 정서유발자극세트는 2-4분 정도의 각 정서 장면이 포함된 총 5개의 동영상 장면들이다. 예비실험을 통해 70% 이상의 적합성 및 효과성을 가진 4개의 세트를 추출하여 본 실험에 사용하였다. 본 실험은 남녀 대학생 12명을 대상으로 4회 반복해서 실시되었다. 실험참여자들은 각 정서 장면을 시청 후, 유발된 정서에 대한 심리적인 평가를 하였다. 측정한 자율신경계 생리반응 변수는 ECG, PPG, EDA, SKT이었다. 연구 결과, 심리반응에서 정서유발자극세트는 75% 이상의 적합성 및 효과성을 보였다. 생리반응(ECG, EDA) 분석 결과, 정서에 따른 자율신경계 반응은 회기별로 일관적이었으며, 각 정서별로 특정적인 생리반응 패턴을 가지는 것으로 나타났다.

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Affective Representation of Behavioral and Physiological Responses to Emotional Videos using Wearable Devices (웨어러블 기구를 이용한 영상 자극에 대한 행동 및 생리적 정서 표상)

  • Inik Kim;Jongwan Kim
    • Science of Emotion and Sensibility
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    • v.27 no.1
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    • pp.3-12
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    • 2024
  • This study examined affective representation by analyzing physiological responses measured using wearable devices and affective ratings in response to emotional videos. To achieve this aim, a published dataset was reanalyzed using multidimensional scaling to demonstrate affective representation in two dimensions. Cross-participant classification was also conducted to identify the consistency of emotional responses across participants. The accuracy and misclassification in each emotional condition were described by exploring the confusion matrix derived from the classification analysis. Multidimensional scaling revealed that the represented objects, namely, emotional videos, were positioned along the rated valence and arousal vectors, supporting the core affect theory (Russell, 1980). Vector fittings of physiological responses also showed the associations between heart rate acceleration and low arousal, increased heart rate variability and negative and high arousal, and increased electrodermal activity and negative and low arousal. Using the data of behavioral and physiological responses across participants, the classification results revealed that emotional videos were more accurately classified than the chance level of classification. The confusion matrix showed that awe, enthusiasm, and liking, which were categorized as positive, low arousal emotions in this study, were less accurately classified than the other emotions and were misclassified for each other. Through multivariate analyses, this study confirms the core affect theory using physiological responses measured through wearable devices and affective ratings in response to emotional videos.

Sensory and Quality Characteristics of Sanyakbyung Prepared with Different Amounts of Glutinous Rice Flour (찹쌀가루 첨가량에 따른 산약병의 기호성 및 품질특성에 관한 연구)

  • Yun, Sook-Ja;Jang, Myung-Sook
    • Korean journal of food and cookery science
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    • v.15 no.6
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    • pp.591-594
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    • 1999
  • An instrumental analysis of Sanyakbyung was carried out along with sensory evaluation to find out how its quality characteristics changed by the addition of glutinous rice flour(0%, 10%, 20%, 30%, 40% and 50%). The moisture content of Sanyakbyung decreased in proportion to the increment of glutinous rice flour. In terms of color, L-value increased depending on the increment of glutinous rice whereas a-value and b-value showed a decrease. This could be accounted for by two factors: one is that the protein contained in yam flour contributed to black coloring and the other is that the color of yam flour itself contributed ostensively to the tint of blackish coloring, and also to the tint of yellow and red coloring. ln the two bite compression test, the hardness, gumminess, chewiness, and cohesiveness of Sanyakbyung decreased depending on the increment of glutinous rice flour. The springiness did not show any significant variation among the samples. That is, the more yam flour was added, the more cohesive and gummy Sanyakbyung was produced. There were significant differences(p<0.05) in the sensory characteristics of the samples in which Sanyakbyung with 10% glutinous rice flour was most preferred in color, those with 20% in flavor, and those with 40% in taste. Adhesiveness and consistency in the palate responses also showed significant differences among samples in which the sample with 40% glutinous rice flour was most favored in consistency. When the content of yam increased, the gumminess also increased. Generally, Sanyakbyung with soft but less gummy texture was preferred to strong gummy one which was easily stuck to teeth. In the overall acceptance, Sanyakbyung with 40% glutinous rice four was most preferred.

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Analysis of Mobility Constraint Factors of Fire Engines in Vulnerable Areas : A Case Study of Difficult-to-access Areas in Seoul (화재대응 취약지역에서의 소방특수차량 이동제약요인 분석 : 서울시의 진입곤란지역을 대상으로)

  • Yeoreum Yoon;Taeeun Kim;Minji Choi;Sungjoo Hwang
    • Journal of the Korean Society of Safety
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    • v.39 no.1
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    • pp.62-69
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    • 2024
  • Ensuring swift on-site access to fire engines is crucial in preserving the golden time and minimizing damage. However, various mobility constraints in alleyways hinder the timely entry of fire engines to the fire scene, significantly impairing their initial response capabilities. Therefore, this study analyzed the significant mobility constraints of fire engines, focusing on Seoul, which has many old town areas. By leveraging survey responses from firefighting experts and actual observations, this study quantitatively assessed the frequency and severity of mobility constraint factors affecting the disaster responses of fire engines. Survey results revealed a consistent set of top five factors regarding the frequency and disturbance level, including illegally parked cars, narrow paths, motorcycles, poles, and awnings/banners. A comparison with actual road-view images showed notable consistency between the survey and observational results regarding the appearance frequency of mobility constraint factors in vulnerable areas in Seoul. Furthermore, the study emphasized the importance of tailored management strategies for each mobility constraint factor, considering its characteristics, such as dynamic or static. The findings of this study can serve as foundational data for creating more detailed fire safety maps and advancing technologies that monitor the mobility of fire engines through efficient vision-based inference using CCTVs in the future.

A Study on the Reliability and Validity of the Five-Visceral Weak Children Questionnaire for Children with Anorexia (식욕부진 소아 대상 오장허약아 설문지의 신뢰도 및 타당도 연구)

  • Ko Mi Mi;Lee Sun Haeng;Chang Gyu Tae;Lee Boram
    • The Journal of Pediatrics of Korean Medicine
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    • v.38 no.2
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    • pp.1-10
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    • 2024
  • Objectives This study aimed to assess the reliability and validity of the Five-Visceral Weak Children Questionnaire (FWCQ) in childhood anorexia and to propose optimal cutoff values. Methods We conducted two surveys, spaced one month apart, targeting the parents of 366 children aged 2-9 years who had been diagnosed with anorexia for at least one month. To evaluate the reliability of the FWCQ, we calculated Cronbach's alpha coefficient and employed the test-retest method. Additionally, correlation analysis was performed between the FWCQ and each visceral question, and discriminant validity was assessed by comparing responses from the anorexic and normal groups. Furthermore, we determined the cutoff value of the spleen weak score, which is closely associated with appetite, for the anorexic group. Results The first survey yielded responses from 336 participants, followed by 171 responses in the second survey conducted one month later. The FWCQ demonstrated high internal consistency (Cronbach's alpha = 0.776), and test-retest results were consistent. The correlation coefficients between the FWCQ and each visceral question were all statistically significant. Moreover, significant discriminant validity was observed between the anorexic and normal groups in the FWCQ score and the heart, spleen, and kidney weak scores. The optimal cutoff value for the spleen weak score in the anorexic group was found to be 5.5 points (with a sensitivity of 73.44% and specificity of 66.47%). Conclusions The FWCQ exhibited strong reliability and validity in children with anorexia.

A Study on the Priorities of Quality Dimensions for the Quality Competitive Advantage (품질경쟁력 향상을 위한 품질요소의 상대적 중요도 연구)

  • Kim, Sung-Hong
    • Journal of Korean Society for Quality Management
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    • v.40 no.2
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    • pp.156-165
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    • 2012
  • The objective of this study is to identify the critical dimensions of comprehensive quality and to prioritize them for improvement of the quality competitive advantage. The critical dimensions, sub-dimensions and measurement items of comprehensive quality were abstracted from literature of quality, and constructed a model of hierarchical structure. 115 experts in four groups(supplier, buyer, consultant, and professor) were participated in pair-wise comparison of quality dimensions, but some of these responses were removed because the overall consistency of evaluator judgements exceed the acceptable ratio of 0.10. The priorities of quality dimensions for industrial and consumption goods were calculated respectively using the analytic hierarchy process(AHP) approach. As a result, product quality had the highest weight of 0.65, followed by support quality(0.18) and service quality(0.17) for industrial goods while product quality also had the highest weight of 0.62, but service quality(0.22) was preferred over support quality(0.16) for consumption goods.