2,370 research outputs found
A methodology for solving single-model, stochastic assembly line balancing problem
Cataloged from PDF version of article.In this paper, a methodology is developed to solve the single-model, stochastic assembly line balancing problem
for the objective of minimizing the total labor cost and the expected incompletion cost arising from tasks not
completed within the prescribed cycle time. The methodology is based on determining an initial DP based solution
and its improvement using a branch-and-bound procedure which uses an approximate solution instead of a lower
bound for fathoming nodes. Detailed experimentation shows the superiority of this method over the most promising
one from the literature. # 1999 Elsevier Science Ltd. All rights reserved
Diamond pixel detector for beam profile monitoring in COMET experiment at J-PARC
We present the design and initial prototype results of a pixellized proton
beam profile monitor for the COMET experiment at J-PARC. The goal of COMET is
to look for charged lepton flavor violation by direct muon to electron
conversion at a sensitivity of . An 8 GeV proton beam pulsed at 100 ns
with protons/s will be used to create muons through pion production
and decay. In the final experiment, the proton flux will be raised to
protons/sec to increase the sensitivity. These requirements of harsh radiation
tolerance and fast readout make diamond a good choice for constructing a beam
profile monitor in COMET. We present first results of the characterization of
single crystal diamond (scCVD) sourced from a new company, 2a systems
Singapore. Our measurements indicate excellent charge collection efficiency and
high carrier mobility down to cryogenic temperatures.Comment: Pixel 2014 Workshop proceedings in JINS
Scheduling independent jobs with stochastic processing times and a common due date on parallel and identical machines
We propose a heuristic procedure that constructs a schedule for N jobs with stochastic processing times and a common due date on M parallel, identical machines. The criterion is the minimization of the total expected incompletion cost. A worst-case analysis for the ratio of the heuristic and optimal solutions is presented and a bound on the ratio is derived. The experimental results presented indicate that the heuristic procedure generates almost optimal solutions. © 1989 J.C. Baltzer A.G. Scientific Publishing Company
Sequencing jobs on a single machine with a common due date and stochastic processing times
This paper presents a procedure for sequencing jobs on a single machine with jobs having a common due date and stochastic processing times. The performance measure to be optimized is the expected incompletion cost. Job processing times are normally distributed random variables, and the variances of the processing times are proportional to their means. The optimal sequences are shown to have a W- or V-shape. Based on this property computationally attractive solution methods are presented. © 1990
Ambiguity and public good provision in large societies
ArticleIn this paper, we consider the effect of ambiguity on the private provision of public goods. Equilibrium is shown to exist and be unique. We examine how provision of the public good changes as the size of the population increases. We show that when there is uncertainty, there may be less free-riding in large societies
Serious physical fighting and gambling-related attitudes and behaviors in adolescents
Background and aims:
Physical fighting and gambling are common risk behaviors among adolescents. Prior studies have found associations among these behaviors in adolescents but have not examined systematically the health and gambling correlates of problem-gambling severity amongst youth stratified by fight involvement.
Methods:
Survey data were used from 2,276 Connecticut high school adolescents regarding their physical fight involvement, gambling behaviors and perceptions, and health and functioning. Gambling perceptions and correlates of problem-gambling severity were examined in fighting and non-fighting adolescents.
Results:
Gambling perceptions were more permissive and at-risk/problem gambling was more frequent amongst adolescents reporting serious fights versus those denying serious fights. A stronger relationship between problem-gambling severity and regular smoking was observed for adolescents involved in fights.
Discussion and conclusions:
The more permissive gambling attitudes and heavier gambling associated with serious fights in high school students suggest that youth who engage in physical fights warrant enhanced prevention efforts related to gambling. The stronger relationship between tobacco smoking and problem-gambling severity amongst youth engaging in serious fights suggest that fighting youth who smoke might warrant particular screening for gambling problems and subsequent interventions
Adolescents’ responses to the promotion and flavouring of e-cigarettes
Objectives
The purpose of the study is to examine adolescents’ awareness of e-cigarette marketing and investigate the impact of e-cigarette flavour descriptors on perceptions of product harm and user image.
Methods
Data come from the 2014 Youth Tobacco Policy Survey, a cross-sectional in-home survey conducted with 11–16 year olds across the UK (n = 1205). Adolescents’ awareness of e-cigarette promotion, brands, and flavours was assessed. Perceptions of product harm, and likely user of four examples of e-cigarette flavours was also examined.
Results
Some participants had tried e-cigarettes (12 %) but regular use was low (2 %) and confined to adolescents who had also smoked tobacco. Most were aware of at least one promotional channel (82 %) and that e-cigarettes came in different flavours (69 %). Brand awareness was low. E-cigarettes were perceived as harmful (M = 3.54, SD = 1.19) but this was moderated by product flavours. Fruit and sweet flavours were perceived as more likely to be tried by young never smokers than adult smokers trying to quit (p < 0.001).
Conclusions
There is a need to monitor the impact of future market and regulatory change on youth uptake and perceptions of e-cigarettes
- …