Efficient frameworks for greedy split and new depth first search split procedures for routing problems

Split procedures have proven their efficiency within global optimization frameworks for routing problems by splitting giant tours into trips. This is done by generating an optimal shortest path within an auxiliary graph constructed from the giant tour. This article provides a state of the art of split practice in routing problems and gives its key features. The efficiency of the method critically depends on the node-splitting procedure and on the upper and lower bound approximations. Suitable complexity can be obtained using a new depth first search procedure which is introduced here and provides a new algorithm that is specially designed for large scale problems with resource constraints. Experiments show that the depth first search split procedure introduced in this article, used as an evaluation function in a global framework, can improve the results obtained by the use of the “classical” split procedure on the Location-Routing Problem and the Heterogeneous Vehicle Routing Problem. The Location-Routing Problem is also used to provide further analysis and a fair comparative study between the two split versions.     

Series production in a basic re-entrant shop to minimize makespan or total flow time

This paper addresses a real life shop scheduling problem in a manufacturing company. In this problem, a set of n identical jobs are to be processed on two machines. Every job visits one of the machines more than once. This is therefore a re-entrant shop. Due to the fact that the jobs are identical, the decision version of this problem is even not in the class NP. We give an optimal schedule to minimize the makespan. Since the total flow time depends on the relations between the processing times, we decompose this problem into sub-problems according to the relations between the processing times. We prove various properties of optimal solutions and, based on these properties, we provide an optimal solution for all the sub-problems except one of them. For the sole remaining sub-problem, we prove a dominance property which allows to consider a part of schedules to find an optimal one.     

Electrochemical investigation of Pb2+ binding and transport through a polymerized crystalline colloidal array hydrogel containing benzo-18-crown-6

The transport of Pb2+ through a sensory gel, a polymerized crystalline colloidal array hydrogel with immobilized benzo-18-crown-6, is important for understanding and optimizing the sensor. Square wave voltammetry at a Hg/Au electrode reveals many parameters. The partition coefficient for Pb2+ into a control gel (no crown ether), K(p), is 1.00 +/- 0.018 (errors reported are SEM). The porosity, epsilon, of the gel is 0.90 +/- 0.01. Log K(c) for complexation in the gel is 2.75 +/- 0.014. Log K(c) in aqueous solution for Pb2+ with the ligand 4-acryloylamidobenzo-18-crown-6 is 3.01 +/- 0.010 with dissociation rate k(d) = (8.34 +/- 0.45) x 10(2) s(-1) and association rate k(f) = (8.79 +/- 0.025) x 10(7) M(-1) s(-1). The partition coefficient of the ligand 4-acryloylamidobenzo-18-crown-6 into the control gel, K(p,L) is 2.07 +/- 0.15. The diffusion coefficient of Pb2+ in the control gel is 6.72 x 10(-6) +/- 0.12 cm(2)/s. For the sensor gel, but not control gel, diffusion coefficients are location dependent. The range of diffusion coefficients for Pb2+ in the probed locations was found to be (6.11-12.60) x 10(-7) cm(2)/s for 0.91 mM Pb2+ and (2.84-9.39) x 10(-7) cm(2)/s for 0.35 mM Pb2+. Lead binding in the sensor gel is slightly less avid than in solution. This is attributed, in part, to the demonstrated affinity of the ligand 4-acryloylamidobenzo-18-crown-6 to the gel. Diffusion coefficients determined for the sensor gel were found to be location dependent. This is attributed to heterogeneities in the crown concentration in the gel. Analysis of diffusion coefficients and rate constants show that diffusion and not chemical relaxation will limit the time response of the material.     

Six case studies of international collaboration in science

Summary This study, based on two empirical investigations undertaken in Croatia on samples of 320 eminent and 840 young researchers, shows a comparison between the professional values/norms of these groups (normative level of research ethics), as well as a comparison (of perceptions) about the frequency of ethically questionable and unacceptable behaviour of researchers in Croatian research institutions (behavioural level of ethos). Science ethics includes a core of cognitive and social standards about which there is relatively high consensus in both groups of researchers. Their cognitive standards correspond to epistemological realism with an accent on objective, reliable, measurable and precise new knowledge. Their basic social values include the broadest social responsibility, responsibility towards colleagues and students, and professionality in relation with funders and/or clients. Thus, research ethos is a combination of traditional cognitive norms and new socially-engaged values. However, research ethics is not a static or homogeneous set of professional values and norms. Young scientists value cognitive norms relating to basic research lower, but rank some cognitive standards more closely linked with applied empirical research higher. Considering the social dimensions of research ethics, young researchers rate traditional academic values of collegiality, communality and autonomy less important than do eminent scientists, but they hold professionalism and establishing research networks more important. As expected, cognitive and social values and norms are not strictly followed on the level of professional practice. In their everyday professional life eminent and young researchers experience particular questionable research practices that could harm research work and results, and impair collegial relations in science, more often than they encounter breaking social norms that harm or even threaten participants in and users of scientific professional work. Differences in perceiving the incidence of certain kinds of questionable behaviour between the eminent and the young may be attributed to their different professional position and experience.     

Two-Dimensional Simulation of Subcritical Flow at a Combining Junction: Luxury or Necessity?

Classically, in open-channel networks, the flow is numerically approximated by the one-dimensional Saint Venant equations coupled with a junction model. In this study, a comparison between the one-dimensional (1D) and two-dimensional (2D) numerical simulations of subcritical flow in open-channel networks is presented and completely described allowing for a full comprehension of the modeling of water flow. For the 1D, the mathematical model used is the 1D Saint Venant equations to find the solution in branches. For junction, various models based on momentum or energy conservation have been developed to relate the flow variables at the junction. These models are of empirical nature due to certain parameters given by experimental results and moreover they often present a reduced field of validity. In contrast, for the 2D simulation, the junction is discretized into triangular cells and we simply apply the 2D Saint Venant equations, which are solved by a second-order finite-volume method. In order to give an answer to the question of luxury or necessity of the 2D approach, the 1D and 2D numerical results for steady flow are compared to existing experimental data.     

Patterns of adjustment among siblings exposed to intimate partner violence.

This research explored and compared patterns of adjustment in siblings exposed to intimate partner violence. The quality of family relationships were investigated as potential mechanisms that accounted for heterogeneity in these patterns. Participants included 47 sibling pairs and their mothers recruited from the community. Mothers and children reported on child adjustment measures and the quality of family relationships. Five cluster patterns were identified for both younger and older siblings, replicating three identified in previous research: primarily internalizing symptoms, a combination of internalizing and externalizing symptoms, and an asymptomatic cluster. There was little overlap in cluster membership within families; most siblings differed in terms of their pattern of adjustment. The quality of family relationships varied significantly across clusters. Overall, asymptomatic siblings reported the most positive family relationships. Maternal warmth differed across clusters for both older and younger siblings, while maternal hostility varied across clusters for older but not younger siblings. The quality of sibling relationships also differed across clusters for older but not younger siblings. These findings underscore the importance of examining differential sibling experiences within violent families, and demonstrate the significance of family relationships as a mediating mechanism influencing heterogeneous child adjustment. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Les variables cognitives impliquées dans l'inquiétude face à la maladie.

The essential feature of Hypochondriasis is preoccupation with fear of having a serious disease based on a misinterpretation of bodily symptoms. While it is classified as a somatoform disorder, it presents many similarities with anxiety disorders, particularly Generalized Anxiety Disorder (GAD) which is core feature is excessive worry. Since these disorders present similar symptoms, it is also possible that similar cognitive mechanisms may be involved in their development and maintenance. The goal of the present study was to verify the relationship between illness worry and cognitive mechanisms related to GAD: Intolerance of uncertainty, faulty believes about the usefulness of worry, negative problem orientation, and cognitive avoidance. Three hundred and forty six adults (N=346) participated in this correlational study by completing relevant questionnaires. Results demonstrated that most GAD mechanisms were significant predictors of illness worry. Cognitive avoidance and negative problem orientation, entered first in the model, were the strongest predictors of the variance in illness worry scores. Faulty beliefs about worry explained only a marginal part of that variance once the first two predictors have been entered. Results also suggested that cognitive avoidance was a better predictor of illness worry compared to somatosensory-amplification, a cognitive mechanism considered as central in understanding Hypochondriasis (see Barsky & Wyshak, 1990). Clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

适应交互智能产品设计需要的素质教育模式

埃因霍温科技大学工业设计系自建系以来就注重培养学生成长为交互智能产品、系统及相关服务的专业设计师.我系创立并实旋了一种新型的以能力素质为中心的教育模式.此模式包括素质架构及建立在这个架构上勤思求变的设计流程两个方面.这个教育模式注重学生学习的方法(目标,方式和原因),从多方面培养学生在新的知识时代成为能够在应对大量不断变化的信息中保持创造性和灵活性的设计师.     

Autonomous, controlled, and amotivated types of academic motivation: A person-oriented analysis.

The authors investigated students' profiles regarding autonomous, controlled, and amotivated regulation and tested whether profile groups differed on some academic adjustment outcomes. Studies 1 and 2 performed on high school students revealed 3 profiles: (a) students with high levels of both controlled motivation and amotivation but low levels of autonomous motivation, (b) students with high levels of both controlled and autonomous motivation but low levels of amotivation, and (c) students with moderate levels of both autonomous and controlled motivations but low levels of amotivation. These first 2 studies revealed that students in the high autonomous/high controlled group reported the highest degree of academic adjustment. Study 3 performed on college students revealed 3 profiles: (a) students with high levels of autonomous motivations but low levels of both controlled motivation and amotivation, (b) students with high levels of both autonomous and controlled motivation but low levels of amotivation, and (c) students with low to moderate levels of the various motivational components. Study 3 indicated that students in the autonomous group were more persistent than students in the other groups. Results are discussed in light of self-determination theory (E. L. Deci & R. M. Ryan, 1985). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender Differences in British Blogging

This article asks whether blogging in the United Kingdom, which started later than in the United States, reproduces the gender differences in blogging behavior and the gender inequalities in recognition that have been observed in studies based largely on U.S. bloggers. A sample of 48 female and male British bloggers answered a questionnaire about their blogging practices and attitudes; data were also collected from their blogs and by means of online tools. For both sexes, blogging is mainly a leisure activity, and men and women find the same range of satisfactions in blogging. However, more women use blogging as an outlet for creative work, whether as a hobby or as a livelihood. The results support several reasons advanced in previous research for the lower public profile of women bloggers.