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1.
SONET (Synchronous Optical NETworks) add-drop multiplexers (ADMs) are the dominant cost factor in the WDM(Wavelength Division Multiplexing)/SONET rings. The number of SONET ADMs required by a set of traffic streams is determined by the routing and wavelength assignment of the traffic streams. Previous works took as input the traffic streams with routings given a priori and developed various heuristics for wavelength assignment to minimize the SONET ADM costs. However, little was known about the performance guarantees of these heuristics. This paper contributes mainly in two aspects. First, in addition to the traffic streams with pre-specified routing, this paper also studies minimizing the ADM requirement by traffic streams without given routings, a problem which is shown to be NP-hard. Several heuristics for integrated routing and wavelength assignment are proposed to minimize the SONET ADM costs. Second, the approximation ratios of those heuristics for wavelength assignment only and those heuristics for integrated routing and wavelength assignment are analyzed. The new Preprocessed Iterative Matching heuristic has the best approximation ratio: at most 3/2.  相似文献   
2.
There is convincing evidence that children who grow up without fathers are vulnerable for psychosocial dysfunction. A document called the Fatherbook is presented for therapeutic work with the father-absent early adolescent boy. Modeled on the life story book used with children in foster care, the Fatherbook records information, thoughts, and feelings about absent fathers. It provides a tangible object with which the youngster can begin to work through the experience of being fatherless. The boy's mother must have the opportunity to voice her feelings about the Fatherbook because the Fatherbook brings the father back into her life as well as her son's.  相似文献   
3.
Due to the great number of Romanian pupils in Spanish public school, the local administration organises extra-curricular Romanian courses in order to preserve the Romanian language and culture. This is a way to contribute to build and consolidate a bicultural and bilingual profile of the young people. Besides, it is also an opportunity to align with plurilingual and pluricultural competence established by The Common European Framework of References for Languages (2002). Based on the premise that “children's literature is an intercultural instrument”, I choose as corpus the Romanian children's folklore represented by games, formula-songs, recital-stories, household words, incantations, riddles and lullabies to translate into Spanish. After the translations, Romanian children had to find similarities and differences between the Romanian and Spanish children's songs, in order to augment the knowledge about both cultures.  相似文献   
4.
Individuals who engage in risky sexual behavior face the possibility of experiencing negative consequences. One tenet of social learning theory is that individuals engage in behaviors partly based on observations or perceptions of others’ engagement in those behaviors. The present study aimed to document these norms–behavior relationships for both risky and protective sexual behaviors, including alcohol-related sexual behavior. Gender was also examined as a possible moderator of the norms–behavior relationship. Undergraduate students (n = 759; 58.0% female) completed a Web-based survey, including various measures of drinking and sexual behavior. Results indicated that students underestimate sexual health-protective behaviors (e.g., condom use and birth control use) and overestimate the risky behaviors (e.g., frequency of drinking prior to sex, typical number of drinks prior to sex, and frequency of casual sex) of their same-sex peers. All norms were positively associated with behavior, with the exception of condom use. Furthermore, no gender differences were found when examining the relationship between normative perceptions and behavior. The present study adds to the existing literature on normative misperceptions as it indicates that college students overestimate risky sexual behavior while underestimating sexual health-protective behaviors. Implications for interventions using the social norm approach and future directions are discussed.  相似文献   
5.
Brought on by increasing levels of economic vulnerability, homelessness is a pressing issue for our schools. Homeless students often miss an inordinate amount of school days and are thought to fall at the farthest end of a “continuum of poverty.” Theoretically they have worse outcomes than their peers, though the past 20 years of literature have found inconsistencies in these comparisons. Thus the literature suggests analysis to compare types of students based on outcomes rather than demographic categorizations, a person-centered approach. Using this approach, a comparison of the number of absences for homeless students and their housed peers is made through quantile analysis. Using school administrative data collected over one school year for an entire school district we found that homeless students as an aggregate do not miss significantly more days of school than their poorest peers. However, we found homelessness and poverty dramatically increase the number of absences for children who are in the higher percentiles of absences meaning homelessness has a greater impact on those who miss more days of school in general compared to regular attendees. Findings from this study indicate that homelessness may exacerbate problems rather than cause them. Implications for practice are discussed and directions for future study are proposed.  相似文献   
6.
A college of social work developed a partnership with a state commission on indigent defense to examine existing data-collection procedures, potential case outcomes, and practical implications of implementing holistic defense programs. The holistic defense model responds to the complex challenges of justice-system-involved defendants by providing social services in public defense offices. Using chi-square and logistic regression analyses of administrative data for a sample of 15,994 public defendants from a single judicial circuit, this research study examined case outcomes before and after implementation of a holistic defense program. Results were mixed regarding effectiveness of holistic defense in mitigating the effect of justice involvement for indigent defendants. Implementation of holistic defense was associated with a decrease in case dismissals. However, defendants receiving holistic representation were less likely to be indicted than defendants prior to program implementation. Once indicted, there were no changes in levels of diversions, and more defendants were held on bond, convicted as guilty, and incarcerated. After program implementation, fewer defendants were sentenced to alternatives to incarceration; more defendants were sentenced to time served, avoiding further incarcerative penalty. These findings suggested the need for further research to determine whether holistic defense practices are producing desired legal and social service outcomes.  相似文献   
7.
The effectiveness of a language-training procedure that emphasized reinforcing vocal “reasonable attempts” (any response directed at an interventionist and within a broader class of correct responses) was compared with a procedure that emphasized shaping (reinforcing successive approximations that more closely resembled the target vocalization). Three preschoolers who had been diagnosed with autism spectrum disorders participated in the study. Data indicated that the children mastered vocal skills more rapidly when they learned through shaping than in the reasonable attempts condition. Implications for teaching children with autism spectrum disorders are discussed.  相似文献   
8.
9.
Financial Issues Associated with Having a Child with Autism   总被引:2,自引:2,他引:0  
Data from the Family Experiences with Autism Survey are used to identify factors associated with financial problems in families that have a child with autism. Likelihood of financial problems was positively associated with use of medical interventions, having unreimbursed medical or therapy expenses, and having relatively lower income. Use of speech and language therapy was negatively associated with likelihood of financial problems. Many survey respondents forfeited future financial security and even experienced bankruptcy to provide needed therapy for a child with autism. Specific ways that financial advisors can help families that have a child with autism are outlined.
Dana Lee BakerEmail:
  相似文献   
10.
The present study examined the relationships between caregivers' self‐reported positive and negative emotional expressiveness, observer assessments of children's emotion regulation, and teachers' reports of children's internalizing and externalizing behaviors in a sample of 97 primarily African American and Hispanic Head Start families. Results indicated that higher caregiver negativity and lower child emotion regulation independently predicted more internalizing behavior problems in children. Additionally, children's externalizing behavior problems were negatively predicted by caregivers' self‐reports of positive emotional expressiveness. Importantly, results also suggested that caregivers' emotional expressiveness and children's behavioral problems may be non‐linearly related, and that child gender may play an important moderating role. These results emphasize the importance of family emotional climate and child emotion regulation in the behavioral development of preschool‐age children, and highlight the need for improved theoretical and practical understanding of socioemotional development in diverse populations.  相似文献   
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