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1.
Seismic force modification factor for ductile structures   总被引：3，自引：0，他引：3  
INTRODUCTION In codes for seismic design of buildings of many developed countries, elastic response spectra are adopted to calculate the base shear forces. For exam-ple, the base shear defined in Japan code 1997 is: FEK=DsFesC0ZAiRtW (1) where Rt is the elastic design spectrum; Ds is the structural coefficient changing among 0.25 to 0.50 to take account of different ductility of different struc-tures; W is the total weight of a structure; the others are site coefficient, irregular…  相似文献   

2.
The Schmid‐Leiman decomposition of a hierarchical factor model converts the model to a constrained case of a bifactor model with orthogonal common factors that is equivalent to the hierarchical model. This article discusses the equivalence and near‐equivalence of the hierarchical and bifactor models and the implications of the difficulty of distinguishing between these models because of low power in samples commonly found in academic research.  相似文献   

3.
1. Introduction Acidic fibroblast growth factor (aFGF), a member of a family of structurally related polypeptides, is a kind of multifunctional protein that can stimulate cellular proliferation, migration and differentiation. In vivo, aFGF displays angiogenic activity promoting vascular endothelial cell mitogenesis as well as chemotaxis and induction of proteases involved in tissue regeneration [1]. Due to this wide range of biological activities, many potential therapeutic usages of aFGF …  相似文献   

4.
Objective: To investigate the factors favoring a positive prognosis for advanced primary peritoneal carcinoma (PPC). Methods: Twenty-four cases meeting the criteria for PPC were analyzed retrospectively for the clinicopathologic profiles. Immunohistochemistry was used to determine the expressions of p53, Top2α, Ki-67 and Her-2/neu. Then all these clinicopathological factors and molecular markers were correlated with the prognosis. Results: There were 15 cases of primary peritoneal serous papillary carcinoma (PPSPC), 6 cases of mixed epithelial carcinoma (MEC) and 3 cases of malignant mixed Mullerian tumor (MMMT). All patients underwent cytoreductive surgery with optimal debulking achieved in 3 cases. Among those receiving first-line chemotherapy, 13 patients received the TP regimen (paclitaxel-cisplatin or carboplatin) and 7 patients received the PAC regimen (cisplatin-doxorubicin-cyclophosphamide). The median overall survival of all patients was 42 months, while the breakdown for survival time for patients with PPSPC, MMT and MEC was 44, 13 and 19 months, respectively. The expressions of p53, Top2a and Ki-67 were all demonstrated in 11 cases respectively. None showed the expression of Her-2/neu. There were significant differences in the median survival between patients with PPSPC and those with MMMT (44 months vs 13 months, P<0.05), also between patients receiving TP combination and those receiving the PAC regimen (75 months vs 28 months, P<0.05). Another significant difference in the median progression-free survival (PFS) was identified between patients with positive p53 immunostaining and those with negative p53 immunostaining (15 months vs 47 months, P<0.05), whereas age, menopausal status, residual tumor size and the other molecular factors did not significantly impact survival. Conclusion: Patients with PPC should be treated with a comprehensive management plan including appropriate cytoreductive surgery and responsive chemotherapy. Overestimating an optimal debulking surgery may not benefit survival. The pathologic subtype, chemotherapy regimen and p53 overexpression were significant prognostic factors.  相似文献   

5.
Filipino parents’ school choice and loyalty: a factor analysis   总被引：1，自引：1，他引：0  
This quantitative study aims to ascertain the significant relationship existing between parents’ profile, and their school choice and school loyalty. Data were gathered using the researcher’s two-part made instrument. Respondents were first asked to fill in a robotfoto for purpose of profiling their baseline characteristics and were later asked to rate listed indicators, using a modified 8-point Likert scale. Using statistical tools such as the ANOVA, factor analysis, correlation, mean, and standard deviation, data were treated indepth. It is interesting to note that although parents are loyal to their alma mater, this does not have a much impact on their choice of school for their children. On the whole, parents’ choice of school is based on its indispensable qualities. Among the three interval-scale profiles of the parent respondents such as age, income, tuition fee payment and number of children, none of these relate to school choice, but age, income, and tuition fee payment negatively relate to school loyalty. From their nominal-scale profiles, significant differences were noted in their school choice when grouped according to civil status, place of work, and terms of payment. With respect to school loyalty, significant differences occurred in their responses when classified according to gender, terms of payment and their active participation in the Parent-Teacher Association (PTA).  相似文献   

6.
This paper explores what work readiness means for two cohorts of graduate engineers, one from a traditional curriculum, the second from a largely project-based curriculum. Professional bodies and employers have defined a set of attributes for engineering graduates so that graduates will be ‘work ready’. Problem-based learning (PBL) is claimed to be a suitable approach to develop such skills. The graduates were interviewed some months after starting work, along with their managers. All the graduates recognised the benefits of taking PBL subjects as well as vacation work, with success in communication attributed more to PBL. Both cohorts had similar learning outcomes, high skill levels in project management, problem solving, communication skills, research and sustainability. A skills gap in ethics was identified for both cohorts of graduates and their managers. Further work is planned to link skill development with undergraduate learning experience.  相似文献   

7.
OBJECTIVE: Previous studies have concluded that shaken baby syndrome occurs more often among Whites than among Blacks. The purpose of this study was to determine whether race is a predictive factor in Shaken Baby Syndrome when population and referral patterns are considered. METHODS: A retrospective medical record review of closed head injuries due to child abuse during the time period January 1992 to July 1997 was conducted at three pediatric tertiary care medical centers in North Carolina. Patients included children, ages 0-4 years, identified from medical record reviews and child abuse databases. Only North Carolina residents were included. The specific rates of shaken baby syndrome in Whites versus non-Whites in the referral area were computed. RESULTS: The difference in the rate of shaken baby syndrome from the referral area was not statistically significant among Whites versus non-Whites (26.7/100,000 versus 38.6/100,000, p = .089) Most of the perpetrators were male (68%), and most victims (76%), lived with their mothers and biologic father or mother's boyfriend. CONCLUSION: Race was not a significant factor in predicting shaken baby syndrome in the referral area studied, and therefore is not a useful factor in targeting groups for intervention.  相似文献   

8.
INTRODUCTION The very dramatic increase in demand for high-rate data transmission stimulated greater re- search efforts in developing wideband wireless communication systems which could support high- rate transmission over wireless channels. But we have to face the challenges from the multi-path effects because multi-path propagation of wire wave is usu- ally seen as a harmful factor which leads to one of the most troublesome radio channel problems. However, the multi-path effects can beco…  相似文献   

9.
48 children from primary 4 in private and public schools (24 from each) were asked to solve 10 arithmetic word problems (involving more or less as the cue word) presented in English and in their native language. Retrospective clinical interviews were also conducted to find out how each child analyzed the meaning of each problem, before deciding which operation to use to solve it. The results revealed that both public and private school children performed better both in skills and in strategies when problems were presented in their native language than when presented in English, but only public school had the result to be significant (P<.025). Also data obtained from the interviews are in accord with psycholinguistic theories concerning the polarized comparative pair of less and more.  相似文献   

10.
INTRODUCTION Platelet activating factor (PAF), a kind of pho-spholipids compound, synthesized and secretedmainly by neutrophilic granulocyte, platelet, is ahighly potent chemical mediator in inflammationand allergic reactions and induces microvascularleakage in several tissues (Chung, 1997). PAFs arefew in vivo, have short half life (only about 30seconds) and rapidly convert to lyso-PAF that hasno bio-activity and is both the metabolite and pre-cursor of PAF (Rao, 1998). Lyso-P…  相似文献   

11.
INTRODUCTION Orthogonal frequency division multiplexing(OFDM) is generally known as an effective techniquefor high data rates and has been adopted by standardssuch as Digital Audio and Video Broadcasting (DABand DVB) (ETSI, 1994; 1997). OFDM is robustagainst frequency selectivity of a multipath channeland the single-tap equalization can be used to detectthe transmitted symbols if frequency-selective fadingchannels are known. Although, the use of pilot tonesis the most robust way …  相似文献   

12.
Abstract

South Africa finds itself with skills shortages in scientifically oriented professions. A major contributor to this has been students’ failure in mathematics. This study set out to identify students who self-reported mathematics anxiety and determine if this was a factor in their studies. Participants were 204 mathematics first-year students registered for degrees in Engineering, Information Technology, and Natural Science. Included in this group were Foundation Year students. Results indicated that the majority of students admitted to higher levels of anxiety. With respect to the different degree programmes, chemistry students reported higher anxiety. Specifically, a negative association was established between performance and mathematics evaluation anxiety. It is concluded that lecturers through investigations such as this can identify and isolate highly anxious mathematics students. Such students may receive remedial psychological help or at least, lecturers may revise their presentation methods to suit these particular students. The study also concluded that there are underlying problems within the teaching and learning of mathematics among the study sample. As is typical of this type of investigation, a number of questions remain unanswered such as what the sources of students’ mathematics anxiety are and how these relate to the variables investigated here. A follow-up study will focus more closely on these issues.  相似文献   

13.
Objective： To observe the value of HbA1c level evaluating the total daily basal insulin dose by continuous subcutaneous insulin infusion （CSII） in 268 patients with type 2 diabetes mellitus, Methods： 5-point capillary blood glucose was monitored in pre- and post-CSII and the insulin dose which could stabilize blood glucose was defined as the total daily dose of insulin, including basal and bolus total dose. Correlation between HbA1c level and total daily dose of insulin in patients with type 2 diabetes mellitus was analyzed. Correlation between HbA1c level and 5-point capillary blood glucose was also analyzed. Results： Obvious correlation was observed between HbA1c level and the basal total daily dose of insulin if HbA1c was more than 9.3% （r=0.635, P〈0.05）. The average of 5-point capillary blood glucose was best correlated with HbA1c and fasting blood glucose next best. Conclusion： HbA1c level can forecast basal total daily dose of insulin in CSII.  相似文献   

14.
Hong Kong has two major economic assets: its geographical location and labour force. Shortage of educated manpower has created a bottleneck hampering economic growth. Substantial emigration flows relating to 1997 is also a problem. Development of higher education and infrastructure are means to ensure sustainable economic growth. The government plans to enable 25% of the relevant age group to attend degree and diploma courses in 1995 through rapid expansion and heavy subsidy.Most families are willing to work hard to provide for their children's education. They believe that their society is full of opportunities, and wealth and education important criteria determining one's social status. While Confucian ethics continue to influence attitudes and values, utilitarian considerations are now significant in the choice of disciplines, extra-curricular activities, staff-student relationship, etc.Rapid expansion of tertiary education creates a shortage of qualified staff and students. Fear of 1997 affects academics' dedication. They have to plan their insurance policy and signs of self-censorship emerge. Meanwhile, localization makes progress and the government begins to support research. Exchanges with China allowed local academics to help Chinese universities to renew their external linkages and establish new curricula.Higher education in Hong Kong has completed its take-off. It has achieved standards of developed countries. In the 1990s, it will attempt to consolidate and improve its quality.This is the updated and revised version of a paper prepared for the conference Hong Kong In Transition 1992 organized by the One Country Two Systems Economic Research Institute in Hong Kong  相似文献   

15.
This paper presents the findings of a pilot study that explored students’ experiences of test anxiety when taking A-level examinations. Four focus groups were convened with a sample of 19 participants in the south of England to explore the triggers of test anxiety and the perceived need for interventions to assist high test-anxious students cope with the examination process. The findings suggested that the participants experienced two types of anxiety: ‘pre-exam anxiety’ (relating to, for example, revision and mock examinations) and ‘exam-day anxiety’ (relating to practical concerns, such as school policy on the arrival of students and the time available to complete the examination). Only three participants reported feeling that their examination performance was significantly impaired by test anxiety; most reported that a degree of anxiety aided their performance. With test anxiety perceived by most participants as motivational and useful, there was little support for any interventions from examination boards, parents or teachers to help reduce or manage test anxiety. However, based on participants’ experiences of the pre-examination period, it is suggested that test anxiety may impede students’ ability to prepare for their examinations, and that interventions during this stage may be useful. The findings also imply that there are some practical steps that could be taken by the educational community to help reduce students’ test anxiety.  相似文献   

16.
There has been substantial research evidence concerning the learning approaches of students in Western and non‐Western contexts. Nonetheless, it has been a decade since research in the South Pacific was conducted on the learning approaches of tertiary students. The present research examined the learning approaches of Fijian and other Pacific Islands students enrolling in a professional‐based education course at the University of the South Pacific. Biggs’ (1987 Biggs, J. 1987. Student approaches to learning and studying, Melbourne: Australian Council for Educational Research.  [Google Scholar]) Study Process Questionnaire was revised to suit the social and cultural contexts before it was distributed among 159 undergraduate students. Exploratory factor analysis and confirmatory factor analysis did not support the theoretical framework of a three‐factor model (Biggs, 1987 Biggs, J. 1987. Student approaches to learning and studying, Melbourne: Australian Council for Educational Research.  [Google Scholar]) and, instead, indicated the existence of a two first‐factor model, emphasising two major types of learning approach – reproducing and meaning (Richardson, 1994 Richardson, J.T.E. 1994. Cultural specificity of approaches to studying in higher education. Higher Education, 27: 449–468. [Crossref], [Web of Science ®] [Google Scholar]). The study’s findings suggest that educators should ensure that assessment and other teaching learning components are aligned constructively to promote the appropriate approach of learning.  相似文献   

17.
Primary science education is a concern around the world and quality mentoring within schools can develop pre‐service teachers' practices. A five‐factor model for mentoring has been identified, namely, personal attributes, system requirements, pedagogical knowledge, modelling, and feedback. Final‐year pre‐service teachers (mentees, n = 211) from three Turkish universities were administered a previously validated instrument to gather perceptions of their mentoring in primary science teaching. ANOVA indicated that each of these five factors was statistically significant (p<.001) with mean scale scores ranging from 3.36 to 4.12. Although mentees perceived their mentors to provide evaluation feedback (95%), model classroom management (88%), guide their preparation (96%), and outline the science curriculum (92%), the majority of mentors were perceived not to assist their mentees in 10 of the 34 survey items. Professional development programmes that target the specific needs of these mentors may further enhance mentoring practices for advancing primary science teaching.  相似文献   

18.
The objectives of this study were twofold: to examine the interaction of academic stress and student resourcefulness on subject grades and to identify the factors of parental support that contribute to student resourcefulness. The participants of this cross‐sectional study were 695 fifth and sixth graders from four major districts in Shanghai. Student resourcefulness was observed to moderate academic stress and subject grades. Moreover, perceived paternal emotional support and maternal informational support contributed significantly to student resourcefulness. The implications of this study for parent education are discussed.  相似文献   

19.
The effects of levels of aggregation on measures of goodness of fit and higher order parameter estimates obtained from confirmatory factor analysis (CFA) were investigated. For a higher order model of academic self‐concept, 3 levels of aggregation were considered—disaggregated, partially disaggregated, and partially aggregated. In the disaggregated model, measured variables represented individual items. In the partially disaggregated model, testlets (groups of 4 items) represented measured variables. In the partially aggregated model, subscale scores represented measured variables. Three indexes of fit were employed: the Tucker‐Lewis Index (TLI), the Comparative Fit Index (CFI), and chi‐square. Solutions for the disaggregated models consistently evidenced poor fit. TLI and CFI values for partially disaggregated and partially aggregated solutions were satisfactory. Standardized parameter estimates were similar across all solutions. Implications of these findings are discussed with consideration of other research on model complexity in CFA.  相似文献   

20.
This article investigates the effect of the number of item response categories on chi‐square statistics for confirmatory factor analysis to assess whether a greater number of categories increases the likelihood of identifying spurious factors, as previous research had concluded. Four types of continuous single‐factor data were simulated for a 20‐item test: (a) uniform for all items, (b) symmetric unimodal for all items, (c) negatively skewed for all items, or (d) negatively skewed for 10 items and positively skewed for 10 items. For each of the 4 types of distributions, item responses were divided to yield item scores with 2,4, or 6 categories. The results indicated that the chi‐square statistic for evaluating a single‐factor model was most inflated (suggesting spurious factors) for 2‐category responses and became less inflated as the number of categories increased. However, the Satorra‐Bentler scaled chi‐square tended not to be inflated even for 2‐category responses, except if the continuous item data had both negatively and positively skewed distributions.  相似文献   

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