LEARNING AND VERIFYING SAFETY CONSTRAINTS FOR PLANNERS IN A KNOWLEDGE‐IMPOVERISHED SYSTEM

We present a Bayesian approach to learning flexible safety constraints and subsequently verifying whether plans satisfy these constraints. Our approach, called the Safety Constraint Learner/Checker (SCLC), infers safety constraints from a single expert demonstration trace and minimal background knowledge, and applies these constraints to the solutions proposed by multiple planning agents in an integrated and heterogeneous ensemble. The SCLC calculates how much to blame plan fragments (partial solutions) generated by the individual planning agents. This information is used when composing these fragments into a final overall plan. In particular, fragments whose safety violations exceed a threshold are rejected. This facilitates the generation of safe plans. We have integrated the SCLC within the Generalized Integrated Learning Architecture, which was designed for Defense Advanced Research Projects Agency (DARPA)’s Integrated Learning (IL) program. The main goal of the IL program is to promote the development and success of sophisticated systems that learn to solve challenging real‐world problems based on a simple demonstration by a human expert and exiguous domain knowledge. We present experimental results showing the advantages of the SCLC on two multiagent problem‐solving tasks that were benchmark applications in DARPA’s IL program.     

Enhancing genetic algorithms for dependent job scheduling in grid computing environments

Genetic Algorithms (GAs) are stochastic search techniques based on principles of natural selection and recombination that attempt to find optimal solutions in polynomial time by manipulating a population of candidate solutions. GAs have been widely used for job scheduling optimisation in both homogeneous and heterogeneous computing environments. When compared with list scheduling heuristics, GAs can potentially provide better solutions but require much longer processing time and significant experimentation to determine GA parameters. This paper presents a GA for scheduling dependent jobs in grid computing environments. A?number of selection and pre-selection criteria for the GA are evaluated with an aim to improve GA performance in job scheduling optimization. A?Task Matching with Data scheme is proposed as a GA mutation operator. Furthermore, the effect of the choice of heuristics for seeding the GA is investigated.     

基于一种新型强迫振荡仪器的呼吸道阻抗测量研究

强迫振荡技术被越来越多地应用于呼吸系统力学研究中。为了检验一种新型强迫振荡仪器的临床应用前景,设计了一组实验用于测量哮喘病人和正常人,从而证明这种新型的仪器对哮喘病诊断是否有帮助。实验征集了5个哮喘病人和5个正常人。测量结果表明:所测得的呼吸系统阻抗在两组人之间有明显差异,展示了这种新仪器在哮喘病诊断中的应用潜力。     

Classes of Split‐plot Response Surface Designs for Equivalent Estimation

When planning an experimental investigation, we are frequently faced with factors that are difficult or time consuming to manipulate, thereby making complete randomization impractical. A split‐plot structure differentiates between the experimental units associated with these hard‐to‐change factors and those that are relatively easy‐to‐change. Furthermore, it provides an efficient strategy that integrates the restrictions imposed by the experimental apparatus into the design structure. In this paper, several industrial and scientific examples are presented to highlight design considerations when a restriction on randomization is encountered. We propose classes of split‐plot response designs that provide an intuitive and natural extension from the completely randomized context. For these designs, the ordinary least‐squares estimates of the model are equivalent to the generalized least‐squares estimates. This property provides best linear unbiased estimators and simplifies model estimation. The design conditions that provide equivalent estimation are presented and lead to design construction strategies to transform completely randomized Box–Behnken, equiradial and small composite designs into a split‐plot structure. Published in 2006 by John Wiley & Sons, Ltd.     

Reciprocal Associations Between Adolescent Sexual Activity and Quality of Youth-Parent Interactions.

The authors examined differences in adolescents' relationships with their parents before and after adolescent first sexual activity. Participants were 13,570 members of the core sample of the National Longitudinal Survey of Adolescent Health (Add Health) Waves 1 and 2. Path analyses examined changes in parent-adolescent closeness, shared activities, and problem-focused interactions associated with changes in sexual activity separately for sons and daughters and for mothers and fathers. Race, religion, age, urbanicity, and parents' education were controls. Results confirm that increased problem-focused interactions and decreased parental closeness and shared activities both precede and follow adolescent sexual activity. Maintaining positive parental relations after adolescent first sexual activity is discussed as a means to reduce risks associated with sex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Testing a Self-Determination Theory Process Model for Promoting Glycemic Control Through Diabetes Self-Management.

A longitudinal study tested the self-determination theory (SDT) process model of health behavior change for glycemic control within a randomized trial of patient activation versus passive education. Glycosylated hemoglobin for patients with Type 2 diabetes (n=159) was assessed at baseline, 6 months, and 12 months. Autonomous motivation and perceived competence were assessed at baseline and 6 months, and the autonomy supportiveness of clinical practitioners was assessed at 3 months. Perceptions of autonomy and competence were promoted by perceived autonomy support, and changes in perceptions of autonomy and competence, in turn, predicted change in glycemic control. Self-management behaviors mediated the relation between change in perceived competence and change in glycemic control. The self-determination process model fit the data well. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

NJTxtr—A Computer Program Based on LASER to Monitor Asphalt Segregation

Abstract: This paper describes the research funded by the New Jersey Department of Transportation to develop an automated technology to monitor segregation during construction of hot-mix asphalt concrete pavements. A Laser-based system was used to measure surface texture and to detect segregation. Two segregated test sections and a control test section were tested to evaluate the applicability of Laser texture method to detect and quantify segregation. Laser texture data were gathered from all three sections. Ratios of texture in segregated areas to that in nonsegregated areas were set as the basis for detection of different levels of segregation. By combining the level of segregation and extent of segregation, an AREA index was developed to determine the acceptability of a pavement section. Based on AREA index, pay adjustment factors were proposed to reduce the payment to account for loss of pavement life due to segregation. Further remedial actions were proposed to correct segregated pavement sections with acceptable AREA index. Based on the above concepts, Windows-based computer program NJTxtr was developed to detect and quantify segregation. This computer program uses the Laser-equipment-collected pavement texture data and determines whether the pavement section is acceptable or unacceptable based on the level of segregation within a pavement section, and provides bonus or penalties to the contractor. The paper describes a novel technology using laser and associated software for construction quality control of asphalt concrete pavements. The proposed methodology was applied to detect segregation in an interstate highway section in New Jersey, and this section was repaved based on visual observation and recommendation from this study.     

A dynamic analysis of chalcopyrite bioleaching in continuous flow reactor systems

A dynamic analysis of chalcopyrite bioleaching was performed in continuous flow systems. In contrast to a previous batch analysis¹ in which the influence of particle surface area on reaction rate was not accounted for, the unsteady‐state change in particle surface area was integrated into the dynamic analysis by application of the modified PBM.² The current study extends the analysis to include the influence of convective flow on the system. It is demonstrated that the analysis can be used to determine feasible control strategies for operating near the steady‐state maximum rate that is stable. Two strategies were evaluated for the purpose of increasing the leaching rates, showing that an increased rate of 56% is feasible. Analysis on experimental data showed that increased rates can be achieved by controlling the biomass concentration and ferric:ferrous ion ratio at an optimum by increasing the solids loading [m/v] in the reactor. © 2011 American Institute of Chemical Engineers AIChE J, 58: 2428–2440, 2012