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61.
闫秋实  张亚楠  李述涛  孙庆文 《爆破》2021,38(1):140-146
我国综合管廊内燃气安全问题亟待研究和解决.为了研究管廊内燃气爆炸荷载特性,在0.11 m×0.11 m×6 m的小尺寸管道内进行甲烷-空气混合气体封闭爆炸实验,研究了在不同点火能量(电极点火-2 J;化学点火-5 J)下,甲烷浓度为7.5% ~13.5%的爆炸波的传播规律.结果表明:燃气爆炸超压峰值随浓度的增大先增加后...  相似文献   
62.
Metabolomics helps identify metabolites to characterize/refine perturbations of biological pathways in living organisms. Pre-analytical, analytical, and post-analytical limitations that have hampered a wide implementation of metabolomics have been addressed. Several potential biomarkers originating from current targeted metabolomics-based approaches have been discovered. Precision medicine argues for algorithms to classify individuals based on susceptibility to disease, and/or by response to specific treatments. It also argues for a prevention-based health system. Because of its ability to explore gene–environment interactions, metabolomics is expected to be critical to personalize diagnosis and treatment. Stringent guidelines have been applied from the very beginning to design studies to acquire the information currently employed in precision medicine and precision prevention approaches. Large, prospective, expensive and time-consuming studies are now mandatory to validate old, and discover new, metabolomics-based biomarkers with high chances of translation into precision medicine. Metabolites from studies on saliva, sweat, breath, semen, feces, amniotic, cerebrospinal, and broncho-alveolar fluid are predicted to be needed to refine information from plasma and serum metabolome. In addition, a multi-omics data analysis system is predicted to be needed for omics-based precision medicine approaches. Omics-based approaches for the progress of precision medicine and prevention are expected to raise ethical issues.  相似文献   
63.
分析及时送修策略下的备件保障过程的特点,总结备件保障概率的函数模型,构建以费用为约束的系统级备件保障概率目标函数,并进行特性分析。然后基于边际效应方法描述备件库存优化流程,并修正各产品初始备件量值,以符合模型边界条件。最后通过具体案例的应用,对模型进行进一步的说明和检验。  相似文献   
64.
张棋飞  桂超  宋莺  孙宝林  戴志锋 《软件学报》2021,32(8):2597-2612
机会网络利用节点移动带来的接触机会传输数据,数据在节点运动过程中捎带转发,保证了节点独立性,但会给数据传输带来影响.以节点的运动特性为切入点设计了基于运动的机会网络路由算法.综合考虑数据传输、数据内容以及应用需求等因素,设计了数据转发优先级评价模型,结合节点活动区间划分方案制定数据传输规则;设计了差异化副本传输策略,在...  相似文献   
65.
Norman Garmezy, a pioneer in research on risk and resilience, died in Nashville, Tennessee, on November 21, 2009, at the age of 91. He was a legendary mentor as well as an eminent scientist in clinical psychology. Norm was born on June 18, 1918, in New York City and grew up in the Bronx in a Jewish neighborhood where educational attainment was highly valued. The scientific study of resilience as conceived by Norman Garmezy, his peers, and students has transformed the science and practice of multiple disciplines, from the molecular level to the global ecosystem, infusing a strength-based and recovery-oriented approach into psychology, education, social work, and psychiatry. Current research on resilience ranges from studies of plasticity in brain development to effective planning for resilience in the context of disaster. Norm’s influential ideas and research earned him international acclaim and many honors for lifetime achievements in science. Throughout his career, Norm held many leadership roles. Throughout his life, Norm spoke with great love about his wife of 63 years, Edie Garmezy (who died just months before him in 2009), and their children. In addition to his work and his family, Norm had three abiding passions—theater, movies, and politics. During the last two decades of his life, Norm and those who loved him endured his long decline from Alzheimer’s, which slowly stole his brilliant mind and hilarious sense of humor. Nonetheless, the incredible spirit and humanity of this giant scholar continued to shine through this terrible disease. To the end of his life, Norm’s face would light up with a smile as he greeted the people he loved, and he would often exclaim, “Wonderful!” Norman Garmezy was a remarkable person and scholar who left an extraordinary legacy of love and work to inspire future generations in their efforts to understand and promote the human capacity for competence and resilience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
Objective: Although current evidence suggests that the positive effects of multisystemic therapy (MST) on serious crime reach as far as young adulthood, the longer term impact of MST on criminal and noncriminal outcomes in midlife has not been evaluated. In the present study, the authors examined a broad range of criminal and civil court outcomes for serious and violent juvenile offenders who participated on average 21.9 (range = 18.3–23.8) years earlier in a clinical trial of MST (C. M. Borduin et al., 1995). Method: Participants were 176 individuals who were originally randomized to MST or individual therapy (IT) during adolescence and averaged 3.9 arrests for felonies prior to treatment. Arrest, incarceration, and civil suit data were obtained in middle adulthood when participants were on average 37.3 years old. Results: Intent-to-treat analyses showed that felony recidivism rates were significantly lower for MST participants than for IT participants (34.8% vs. 54.8%, respectively) and that the frequency of misdemeanor offending was 5.0 times lower for MST participants. In addition, the odds of involvement in family-related civil suits during adulthood were twice as high for IT participants as for MST participants. Conclusions: The present study represents the longest follow-up to date of an MST clinical trial and demonstrates that the positive impact of an evidence-based youth treatment such as MST can last well into adulthood. Implications of the authors' findings for policymakers and service providers are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
67.
Although survey results seem to indicate an abundant interest among Canadian psychology graduate students in pursuing training in criminal justice psychology, the recruitment and retention of psychologists in the Correctional Service of Canada (CSC) has been of some concern. The present study is a 2008 survey of sites within CSC that provide opportunities for clinical psychology training with offender clientele. Survey findings demonstrated that a broad range of clinical psychology training opportunities were available across 16 sites. The most frequently cited barrier to providing training was lack of time by prospective trainers, and sites reported retaining relatively few of their trainees for subsequent psychologist positions. Information was also obtained regarding vacant psychologist positions across CSC regions. In light of survey findings, substantive discussion is devoted toward the issues of psychologist recruitment and retention in Canadian federal corrections, including a discussion of both potential and existing training initiatives. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
68.
Assessing a patient's access to potentially lethal means for suicide and taking steps to restrict access to means are common expectations for reasonable outpatient management of suicidal patients. Although scientific evidence supports means restriction as a suicide prevention strategy, means restriction continues to be infrequently utilized by clinicians, in large part because of the general lack of available training and guidance. The present article reviews the conceptual basis and empirical evidence for means restriction, discusses common barriers to means-restriction counseling, and provides practical procedures and tools (e.g., the means receipt, the crisis support plan) for accomplishing means-restriction counseling in routine clinical practice. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
69.
High utility pattern (HUP) mining is one of the most important research issues in data mining. Although HUP mining extracts important knowledge from databases, it requires long calculations and multiple database scans. Therefore, HUP mining is often unsuitable for real-time data processing schemes such as data streams. Furthermore, many HUPs may be unimportant due to the poor correlations among the items inside of them. Hence,the fast discovery of fewer but more important HUPs would be very useful in many practical domains. In this paper, we propose a novel framework to introduce a very useful measure, called frequency affinity, among the items in a HUP and the concept of interesting HUP with a strong frequency affinity for the fast discovery of more applicable knowledge. Moreover, we propose a new tree structure, utility tree based on frequency affinity (UTFA), and a novel algorithm, high utility interesting pattern mining (HUIPM), for single-pass mining of HUIPs from a database. Our approach mines fewer but more valuable HUPs, significantly reduces the overall runtime of existing HUP mining algorithms and is applicable to real-time data processing. Extensive performance analyses show that the proposed HUIPM algorithm is very efficient and scalable for interesting HUP mining with a strong frequency affinity.  相似文献   
70.
《Ergonomics》2012,55(7):656-664
This study characterises weight distribution symmetry between the intact and amputated limbs of unilateral transtibial amputees during a sit-to-stand movement. A total of 12 amputees and 12 age-matched, non-amputees performed the activity for two conditions – rising with and without chair arm-rest assistance. The sit-to-stand movement was divided into five events: Pre-Ascent; Ascent Initiation; Seat-Off; Deceleration; Standing. Symmetry in ground reaction forces between limbs was calculated at each event together with the rise time. Results indicate that during the course of the movement, amputees increased loading of the intact limb by approximately 27%, resulting in a significant asymmetry at seat-off and deceleration events. Non-amputees loaded the dominant limb more than the non-dominant limb throughout the activity but did not exhibit substantial weight shifts. Weight distribution symmetry was not significantly different between the two rising conditions in either population. Amputees had significantly longer rise times than non-amputees only while rising without arm-rest assistance.

Statement of Relevance: Sit-to-stand movements are performed frequently every day. Incorrect movement biomechanics caused by musculoskeletal impairments can lead to reduced functional independence and secondary co-morbidities. This study defines five events of a sit-to-stand cycle and is the first to address asymmetries of transtibial amputees, providing ergonomic insights for clinical assessment and intervention.  相似文献   
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