1,712 research outputs found

    Unicast Barrage Relay Networks: Outage Analysis and Optimization

    Full text link
    Barrage relays networks (BRNs) are ad hoc networks built on a rapid cooperative flooding primitive as opposed to the traditional point-to-point link abstraction. Controlled barrage regions (CBRs) can be used to contain this flooding primitive for unicast and multicast, thereby enabling spatial reuse. In this paper, the behavior of individual CBRs is described as a Markov process that models the potential cooperative relay transmissions. The outage probability for a CBR is found in closed form for a given topology, and the probability takes into account fading and co-channel interference (CCI) between adjacent CBRs. Having adopted this accurate analytical framework, this paper proceeds to optimize a BRN by finding the optimal size of each CBR, the number of relays contained within each CBR, the optimal relay locations when they are constrained to lie on a straight line, and the code rate that maximizes the transport capacity.Comment: 7 pages, 4 figures, 1 table, in IEEE Military Commun. Conf. (MILCOM), 201

    Preliminary study of thermomechanical fatigue of polycrystalline MAR-M 200

    Get PDF
    Thermomechanical fatigue (TMF) experiments were conducted on polycrystalline MAR-M 200 over a cyclic temperature range of 500 to 1000 C. Inelastic strain ranges of 0.03 to 0.2 percent were imposed on the specimens. The TMF lives were found to be significantly shorter than isothermal low-cycle-fatigue (LCF) life at the maximum cycle temperature, and in-phase cycling was more damaging than out-of-phase cycling. Extensive crack tip oxidation appeared to play a role in promoting the severity of in-phase cycling. Carbide particle - matrix interface cracking was also observed after in-phase TMF cycling. The applicability of various life prediction models to the TMF results obtained was assessed. It was concluded that current life prediction models based on isothermal data as input must be modified to be applicable to the TMF results

    Real-Time Quantitative PCR - Primer Design, Reference Gene Selection, Calculations and Statistics

    Get PDF
    Real-time quantitative PCR is a technique that can measure the content of the target nucleic acid sequence of interest in a given sample. It is mainly divided into absolute and relative quantitative methods. The relative quantification is mainly used in gene expressions for functional genomic and transcriptome studies. However, to use this technology accurately, there are some key points to master. First, specific primers need to be designed to ensure amplification of the gene of interest (GOI). Second, the appropriate reference gene or reference gene combination has to be selected. Finally, scientific gene expression level calculations and statistics are required to obtain accurate results. Therefore, this work proposes a workflow for relative quantitative PCR and introduces the relevant points so that beginners can better understand and use this technology

    Can Skills Training Prevent Relationship Problems in At-Risk Couples? Four-Year Effects of a Behavioral Relationship Education Program

    Get PDF
    Eighty-three couples were stratified into groups at high and low risk for relationship distress and randomized to either the Self-Regulatory Prevention and Relationship Enhancement Program (Self-PREP) or a control condition. As predicted, there were differential effects of Self-PREP on high-risk and low-risk couples. Because of low statistical power, results must be interpreted cautiously, but at 1-year follow-up high-risk couples in Self-PREP showed trends toward better communication than control couples. However, there was no difference in the communication of Self-PREP and control low-risk couples. High-risk couples receiving Self-PREP exhibited higher relationship satisfaction at 4 years than control couples, but in low-risk couples relationship satisfaction was higher in the control condition. High-risk couples seemed to benefit from skills-based relationship education, but low-risk couples did not

    Behavioral Marital Therapy: An Evaluation of Treatment Effects Across High and Low Risk Settings

    Get PDF
    The present study examined the generalization of treatment effects of a cognitive- behavioral treatment program for marital distress. Following a baseline phase, each of four couples received two phases of marital therapy within a multiple baseline across subject design. The first phase of treatment was behavioral marital therapy (BMT) focusing on communication and problem solving skills. The second phase was cognitive- behavioral marital therapy (CBMT) which focused on conflict management skills in high risk interactive settings at home. Couples’ communication was assessed in a training setting in the clinic and each of two generalization probe settings at home (a low risk and a high risk) setting. The BMT phase produced a clear reduction in communication negativity in the training setting which generalized to both the low and the high risk setting. The CMBT phase produced little additional changes in communication, however, it was associated with changes on a measure of positive and negative partner- referent thoughts

    Parental divorce and premarital couple communication

    Get PDF
    On the basis of a social learning analysis, it was hypothesized that a history of parental divorce would predispose partners to difficulties in managing conflict. Ninety-three engaged couples were videotaped while they discussed two areas of conflict. Each partner then completed a video-mediated recall procedure, an assessment of cognition during the interactions, which was then coded and analyzed. As predicted, couples in which the woman's parents had divorced showed more negative communication and cognitions during conflict discussions than did couples in which neither partner's parents had divorced. Contrary to predictions, couples in which the man's parents had divorced did not differ from couples in which neither partner's parents had divorced. The current research shows that, at least for women, a history of parental divorce is associated with more negative couple communication before marriage

    A comparison of the generalization of behavioral marital therapy and enhanced behavioral marital therapy

    Get PDF
    This study examined the generalization of behavioral marital therapy (BMT) and enhanced behavioral marital therapy (EBMT), which added cognitive restructuring, affect exploration, and generalization training to BMT. Couples’ communication and cognitions were assessed in the clinic and at home. Both BMT and EBMT were effective in decreasing negative communication behaviors and cognition across settings, but there was little evidence of differential generalization or change between the treatments. A series of regression equations showed no significant association between the extent of change in communication or cognitions and change in frequency of marital disagreements or marital satisfaction. It is concluded that BMT results in impressive generalization of communication and cognitive change, but it remains to be demonstrated that these changes are crucial to improvements in marital satisfaction

    First passage time of N excluded volume particles on a line

    Full text link
    Motivated by recent single molecule studies of proteins sliding on a DNA molecule, we explore the targeting dynamics of N particles ("proteins") sliding diffusively along a line ("DNA") in search of their target site (specific target sequence). At lower particle densities, one observes an expected reduction of the mean first passage time proportional to 1/N**2, with corrections at higher concentrations. We explicitly take adsorption and desorption effects, to and from the DNA, into account. For this general case, we also consider finite size effects, when the continuum approximation based on the number density of particles, breaks down. Moreover, we address the first passage time problem of a tagged particle diffusing among other particles.Comment: 9 pages, REVTeX, 6 eps figure

    Translating employee-driven innovation in healthcare: Bricolage and the mobilization of scarce resources

    Get PDF
    With top-down models of innovation failing to address the entrenched problems of healthcare, policy-makers have proposed that staff working on the frontline might be better placed to innovate solutions. Drawing on a study of employee-driven innovation in UK public healthcare, the authors explore the process through which staff innovate without the resources that support policy implementation, showing how the translation of ideas from problematization to practice is underpinned by ‘bricolage’—the appropriation and repurposing of resources ‘at hand’. IMPACT This paper clarifies how staff innovate services on the ground when resources are scarce. The authors suggest that, where employees—clinicians and practitioners—are driving innovation, they engage in a creative process to mobilize resources; appropriating and repurposing local funding, available space, delivery models and even the labour of staff at all levels. This bricolage provides necessary support to the contingent, and often lengthy translation of employees’ innovation ideas into practice. These insights become more critical in a post-pandemic context that demands innovative solutions to new service delivery challenges
    • …
    corecore