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961.
This paper improves the modeling method for the device with characteristic family presented by L. O. Chua (1977) and results in the one-dimensional fluctuating canonical piecewise-linear model. It is an efficient model. The algorithm for canonical piecewise-linear dynamic networks with one dimensional fluctuating model is discussed in detail. 相似文献
962.
Mobile terminals have evolved from basic portable telephones to complex and diverse devices that encompass dozens of other features, ranging from tri‐dimensional games to office suites with data transmission capabilities. Variability is value: mobile terminal manufacturers must succeed in fulfilling the requirements of hundreds of mobile telecom operators worldwide, and at the same time increase the value of their brand by adopting a common user interface style while offering the features that the target end‐user category desires. This makes for practically infinite variability and creates a business problem. The complexity of the variability problem increases due to issues such as the ability to ‘plug and play’ and ‘feature descension’ (the down‐scaling of high‐end features and their introduction into lower‐end models). The main lesson we have learned from our experience in this field is that the application of relatively simple architectural patterns usually eases up management of the complexity at the architectural level. However, tackling the variability problem at the technical level is ineffective unless the organization is able to ensure the application of the solutions. We analyze the main challenges that lie behind the variability problem in mobile terminals, at both technical and organizational level, and illustrate some of the solutions we have implemented together with our product developers and system architects. Our experience calls for more applied research in the area of variability management, as well as for a number of enhancements to academic curricula. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
963.
Leinonen Jenni A.; Solantaus Tytti S.; Punam?ki Raija-Leena 《Canadian Metallurgical Quarterly》2003,17(3):409
This study focused on how factors outside the home affect the quality of mothering and fathering. Economic pressure and workload were evaluated along with the compensating role of social support on parenting. Information was gathered from 842 mothers and 573 fathers including 139 single-mother and 21 single-father families. The results showed that the nature of the strains, together with parental gender and family structure, influenced their effects on parenting. The results further revealed some gender- and strain-specific protective functions of social support on parenting. For example, economic pressure was related to increased punitive parenting, which was compensated by instrumental and emotional support among the mothers. Workload was related to less authoritative single fathering, which was compensated by instrumental support. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
964.
Rea Margaret M.; Tompson Martha C.; Miklowitz David J.; Goldstein Michael J.; Hwang Sun; Mintz Jim 《Canadian Metallurgical Quarterly》2003,71(3):482
Recently hospitalized bipolar, manic patients (N=53) were randomly assigned to a 9-month, manual-based, family-focused psychoeducational therapy (n=28) or to an individually focused patient treatment (n=25). All patients received concurrent treatment with mood-stabilizing medications. Structured follow-up assessments were conducted at 3-month intervals for a 1-year period of active treatment and a 1-year period of posttreatment follow-up. Compared with patients in individual therapy, those in family-focused treatment were less likely to be rehospitalized during the 2-year study period. Patients in family treatment also experienced fewer mood disorder relapses over the 2 years, although they did not differ from patients in individual treatment in their likelihood of a first relapse. Results suggest that family psychoeducational treatment is a useful adjunct to pharmacotherapy in decreasing the risk of relapse and hospitalization frequently associated with bipolar disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
965.
NZP族陶瓷粉体的合成方法 总被引:5,自引:0,他引:5
陈玉清 《山东轻工业学院学报》1995,9(4):32-38
简述了NZP族陶瓷粉体制备中所采用的几种合成方法的基本原理,对比了传统的固相合成、先进的共沉淀法,水热合成法及溶胶凝胶法的各自特点。 相似文献
966.
Comments on the article by Carlson and Grotevant (see record 1988-17683-001). Carlson and Grotevant's article in this issue provides an excellent and thoughtful overview of observational rating scales as applied to entire family units. Although originally viewed as "clinical" in nature, and lacking in respectable scientific rigor and precision, these assessment devices now have become a useful and flexible approach to the complicated process of family assessment. Notwithstanding the authors' scholarly discussion of issues in utilizing these methods, and their critical review of existing rating formats, I wish to raise three points for discussion: The first concerns the relationship of micro- to macroanalytic procedures, the second focuses on reliability, and the third raises a troubling theoretical issue. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
967.
家庭用电的一些问题的探讨 总被引:1,自引:1,他引:0
针对我国家庭用电设计的一些问题,从用电负荷的确定、导线选择、插座、刀闸等方面,介绍了国际关于电气设计的内容及要点,以满足我国家庭用电的要求,确保家庭用电的安全。 相似文献
968.
In this study, the author describes the nature and occurrence of knowledge-construction links (KCLs) in 3 6th-grade classrooms that varied in degree of learner centeredness. KCLs are operationalized as prior learning that students bring to their current classroom experiences and include school and nonschool experiences. They are hypothesized to facilitate a knowledge-construction process that values prior learning. In the more learner-centered classroom, KCLs occurred in conjunction with open and divergent dialogue, positive reactions to students' use of prior learning, and opportunities within the classroom that allowed students to gain new experiences on which they could draw in further knowledge-construction efforts. In contrast, KCLs were ignored or viewed as inappropriate in the least learner-centered classroom, dialogue about content was convergent, and performance goals were the norm. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
969.
Sagrestano Lynda M.; Paikoff Roberta L.; Holmbeck Grayson N.; Fendrich Michael 《Canadian Metallurgical Quarterly》2003,17(1):108
This research examines longitudinally associations between family risk factors and child and parent depression in 302 urban, low-income, African American adolescents (ages 9-15) and their parents across 2 waves of data collection. Diagnostic data revealed that 7.3% of parents and 3.0% of children at Time 1 and 5.4% of parents and 2.8% of children at Time 2 were clinically depressed. Regression analyses revealed that changes in family functioning were concurrently associated with changes in depression for both children and parents. Specifically, increases in conflict and decreases in parental monitoring were associated with increases in child depressive symptomatology, and increases in conflict and decreases in positive parenting were associated with increases in parental depressive symptomatology. Findings are discussed within a framework of understanding family protective factors and the prevention of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
970.
Owens Elizabeth B.; Hinshaw Stephen P.; Kraemer Helen C.; Arnold L. Eugene; Abikoff Howard B.; Cantwell Dennis P.; Conners C. Keith; Elliott Glen; Greenhill Laurence L.; Hechtman Lily; Hoza Betsy; Jensen Peter S.; March John S.; Newcorn Jeffrey H.; Pelham William E.; Severe Joanne B.; Swanson James M.; Vitiello Benedetto; Wells Karen C.; Wigal Timothy 《Canadian Metallurgical Quarterly》2003,71(3):540
Using receiver operating characteristics, the authors examined outcome predictors (variables associated with outcome regardless of treatment) and moderators (variables identifying subgroups with differential treatment effectiveness) in the Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD; MTA). Treatment response was determined using parent- and teacher-reported ADHD and oppositional defiant symptoms, with levels near or within the normal range indicating excellent response. Among 9 baseline child and family characteristics, none predicted but 3 moderated treatment response. In medication management and combined treatments, parental depressive symptoms and severity of child ADHD were associated with decreased rates of excellent response; when these 2 characteristics were present, below-average child IQ was an additional moderator. No predictors or moderators emerged for behavioral and community comparison treatments. The authors discuss conceptual and clinical implications of research on treatment moderators. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献