A research on problems of mixed-line production and the re-scheduling

This paper is to establish and solve the re-scheduling problems under a flow-shop mixed-line production planning. A case study of the final stage, module manufacturing, of TFT-LCD is provided for illustration of the developed mechanism. In this research, the mixed-line production system and its rescheduling problems are discussed. The buffer management and the DBR scheduling methods based on the Theory of Constraints are used to detect, identify, and level the bottleneck problems in the system. The direct contribution of the results is to increase the production flexibility and mobility of the manufacturing scheduling system and to benefit the entire members of supply chain system. The simulation software, Flexsim, is used to construct and evaluate the developed model, some phenomena of simulated system performance on the maximum delay of orders, the total cost of delay, and make span are discussed.     

Postural support strategies of disabled drivers and the effectiveness of postural support aids

The paper discusses a series of driving trials that were conducted to investigate postural stability of disabled drivers and to assess the effectiveness of a representative sample of support aids. Twenty-three disabled drivers with varying levels of physical disability and seven non disabled drivers participated in the study. The test car was equipped with transducers to measure vehicle velocity and acceleration (longitudinal and lateral), steering wheel movement and torque, and the bracing forces exerted by the driver on the steering wheel. Video cameras were installed to record postural support strategies and displacement of the driver and to record deviation of the car from the specified path. Subjective data regarding driver attitudes and acceptance were also collected through the administration of questionnaires. Findings from the study showed that support aids significantly improved driving performance and reduced physical exertion to maintain an upright driving position for disabled drivers. However, ergonomics design aspects regarding the ease of use and acceptance of the support aids by the end users were identified as obstacles to their sustained use in everyday driving.     

Hamilton's principle as substationarity principle

Summary The present paper deals with Hamilton's principle for nonconvex, generally non-differentiable functions. It is shown that in this case Hamilton's principle can be formulated as a substationarity principle which is a generalization of a stationarity principle. To this end the recently defined notion of Clarke's generalized gradient is used. Finally a generalization of modified Hamilton's principle is discussed.With 1 Figure     

Numerical characterization and experimental verification of an in-plane MEMS-actuator with thin-film aluminum heater

In this paper, a novel concept of a thermo-mechanical MEMS actuator using aluminum thin-film heaters on a thermal oxide for electrical insulation is presented. The actuator is part of an universal tensile testing platform for thermo-mechanical material characterization of one dimensional materials on a micro- and nano-scopic scale under different environmental conditions, as varying temperatures, pressure, moisture or even vacuum and is realised in BDRIE technology. It is shown, that the actuator concept fulfills the requirements for the use in a tensile loading stage along with heterogeneously integrated nanofunctional elements, following a specimen centered approach in line with bottom-up self-assembly processes. Simulation and experiment agree very well in the thermal and mechanical domain and allow subsequent optimisation of the actuator performance.     

2.17 Joule heating in ZnS electroluminescent films

The current (i)-voltage (V) characteristics of ZnS electroluminescent films have been interpreted taking into account Joule heating. Graphs of log i vs log V for dc data showed a square law behaviour up to a critical power which was sample-dependent. At higher powers, the data lay on a straight line of increased slope (typically 2.5). A comparison of the i-V characteristics of a sample under dc and pulsed voltage excitation showed that the pulsed characteristics followed a square law in the voltage range which gave enhanced conduction under dc conditions. By assuming a simple law of cooling to be obeyed, the activation energy relating the pulsed and dc currents at corresponding voltages was calculated. It was also possible to explain the variation in critical power from sample to sample. Estimates of the temperature at the critical power suggested a phase change associated with the copper sulphide present in the devices. Examination of the i-V data reported by other workers proved to be consistent with those reported here. It is argued that this approach may therefore have a more general validity.     

Modeling ceramic filled polymer integrated capacitor formationusing neural networks

Integrated decoupling capacitors for MCM-L/D technology are an important component for next-generation electronic packaging applications. This paper presents a statistically designed experiment for systematic characterization of the dielectric constant and loss tangent of integrated capacitors formed by mixing lead magnesium niobate (PMN) particles into polyimide and benzocyclobutene (BCB) polymer dielectric layers. We determine these quantities as a function of the type of polymer material, a volume fraction of ceramic in the polymer matrix, a polymer cure time, and polymer cure temperature. These factors have been examined by means of a D-optimal experiment. Results indicate manipulation of each of the four factors over the ranges examined lead to considerable variation in dielectric constant and loss tangent. Based on data from these experiments, we train neural networks to model this process variation as a function of above variables. Using this methodology, we determine proper combinations of polymer/ceramic materials and processing conditions to achieve desirable electrical properties     

Merocyanine 540 as a fluorescence indicator for molecular packing stress at the onset of lamellar-hexagonal transition of phosphatidylethanolamine bilayers

The fluorescence of Merocyanine 540 (MC 540) is sensitive to the molecular packing of membrane lipids. Therefore, the fluorescence of MC 540 is expected to be sensitive to the curvature-related packing stress at the onset of the lamellar-hexagonal phase transition. We measured the fluorescence intensity of MC 540 when the temperatures of lipid bilayers approached their lamellar-hexagonal phase transitions. The fluorescence of MC 540 in the presence of egg and dioleoylphosphatidylethanolamine bilayers increased at the respective lamellar-hexagonal phase transitions of these lipids. Furthermore, increases in fluorescence intensity were also observed at temperatures just below their phase transitions. The enhanced fluorescence was not due to the specific interaction of the dye with the ethanolamine headgroup, because no such increase was observed when the probe was exposed to phosphatidylethanolamines which do not form hexagonal phase within the range of applied temperature. In addition, when the temperature of the lamellar-hexagonal phase transition was shifted, by the addition of a small amount of phosphatidylcholine, the dependence of the fluorescence intensity on temperature was modified accordingly. We postulate that the change of MC 540 fluorescence intensity at temperatures approaching the lamellar-hexagonal phase transition reflects changes in the partition of MC 540 into the fluid lipid phase. The change in partition is influenced by the curvature stress in bilayers at temperatures just below the lamellar-hexagonal phase transition.     

Why are we here at the clinic? Parent–child (dis)agreement on referral problems at outpatient treatment entry.

Do clinic-referred children and their parents agree on the problems for which treatment is undertaken? The authors asked 381 outpatient-clinic-referred children and their parents to list, independently, the child's target problems. Of the parent-child pairs, 63 % failed to agree on even a single problem. When problems were grouped into broad categories (e.g., delinquent, withdrawn), more than a third of the pairs still failed to agree on a single broad problem area. Parent-child agreement was higher for externalizing than for internalizing problem categories (though poor for both). Low parent-child agreement may help explain the poor outcomes often reported for clinic-based child therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential regulation of angiotensinogen and AT1A receptor mRNA within the rat subfornical organ during dehydration

The present study describes the differential rostro-caudal patterning of angiotensinogen (AoGen) and AT1A receptor mRNAs in the rat SFO using specific and validated oligodeoxynucleotide probes for in situ hybridization. Highest levels of AoGen-specific gene expression were observed in the rostral region of the SFO with gradually decreasing intensity towards the caudal region of this sensory circumventricular organ lacking blood-brain barrier function. AoGen-related hybridization signals proved to be specifically prominent above cells in lateral aspects of the SFO, surrounding septal venules. Maximal expression of the AT1A receptor-specific gene, on the other hand, could be detected in the neuron-enriched, ventro-medial core region and dorsal annulus of the SFO, with low-intensity hybridization signals in its rostral and caudal parts. Water deprivation for 48 h, leading to extracellular hypertonic hypovolemia with elevated circulating AngII concentrations within the physiological range, caused a significant increase in AoGen-specific hybridization signals in the rostral and medial SFO regions. AT1A receptor gene expression and AngII receptor binding were markedly stimulated in the medial and caudal regions of the SFO (core and annulus) as compared to euhydrated animals. These data indicate, that mild dehydration differentially up-regulates AoGen- and AT1A receptor-specific mRNA formation as well as AT1 receptor binding in distinct regions of the SFO, and supports the involvement of different cellular subgroups in the expression of two major components of the central nervous renin-angiotensin system in this sensory circumventricular organ.