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Lot sizing in queuing networks is pivotal to batch manufacturing, especially in stochastic environments. Despite development in lot sizing optimisation, the results are often rendered unrealistic because few studies have considered the impacts of relevant environmental regulation policies on production planning. This paper incorporates stochastic lot sizing optimisation with two dominant carbon emission reduction mechanisms – the carbon emission constraint and the cap-and-trade system – to examine their operational and environmental impacts on make-to-order manufacturing. It also compares these two mechanisms in environmental conservation. Numerical experiments validate the importance of considering the carbon emission regulations to traditional production planning problems. The results highlight that the market-based characteristics of the cap-and-trade mechanism motivate firms with economic benefits to adopt low-carbon technologies and environmental-friendly facilities to curb greenhouse gases emission. In contrast, the carbon emission constraint mechanism is like administrative orders to force out outmoded industries and outdated technologies. [ABSTRACT FROM AUTHOR]

Current research in production planning focuses mainly on optimising operational objectives, taking little consideration of the primary principle of corporate governance and investor interests. Such approaches often overlook the critical roles of the cost structure and financial position of a firm, rendering the optimisation results unreliable. This paper studies stochastic lot sizing optimisation in make-to-order manufacturing, with an aim to maximise the full investor interests, well known as shareholder wealth. It presents a relatively simple yet reliable lead time model based on probability theory and stochastic processes. Moreover, the impacts of macroeconomic factors are examined to seek potential drivers for shareholder wealth. Theoretical optimality properties are proved to validate the effectiveness of the proposed model in dealing with batch production planning. Numerical examples and analytical results are presented to illustrate the significance of considering such economic and financial constraints and shareholder wealth. These results highlight that the proposed model can help improve shareholder wealth, and that it is a useful tool for examining the potential challenges and opportunities of shareholder wealth creation in production planning. [ABSTRACT FROM PUBLISHER]

The advantage of supplemental sodium bicarbonate (NaHCO3) on eggshell quality in laying hens changes with age. Besides increasing calcium (Ca) secretion in the eggshell gland, it may improve Ca absorption in the intestine or kidney.Hy-Line Brown layers (n = 384), 25 weeks of age, were allocated to two treatment groups in two experiments, each of which included 4 replicates of 24 hens. Hens were fed a basal diet (control) or the basal diet containing 3 g NaHCO3 g/kg for 50 or 20 weeks in Experiment 1 or 2, respectively. A 24-h continuous lighting regimen was used to allow hens to consume the dietary supplements during the period of active eggshell formation.In Experiment 1, particularly from 25 to 50 weeks of age, and in Experiment 2, NaHCO3 supplementation favoured hen-d egg production at the expense of lower egg weight. The increased eggshell thickness should have nothing to do with the additional eggshell formation, because of the unchanged egg mass and daily eggshell calcification.At 35 weeks of age in both experiments, NaHCO3 supplementation increased duodenal expression of calbindin-d28k (CaBP-D28k) protein, contributing to higher Ca retention and balance.From 50 to 75 weeks of age in Experiment 1, the hens had little response to NaHCO3 supplementation and showed a negative trend on eggshell thickness and strength.It is concluded that dietary supplementation with 3 g NaHCO3 g/kg improves Ca absorption and eggshell quality of laying hens during the peak but not late production period, with the introduction of continuous lighting. [ABSTRACT FROM AUTHOR]

To realize the long-term storage of liquid hydrogen for space application, different cooling enhancement components to control the pressure of the cryogenic tanks to a safety condition have been developed in the past decades. In this article, a microgravity, three-dimensional model of a liquid hydrogen storage system with heat pipe and pump-nozzle unit was built. Focusing on significant factors to the cooling performance, such as the heat transfer efficiency of the cool tip (evaporation section), the spraying direction of the nozzle, and the number of the pump-nozzle units, numerical simulations of six tanks with different components were carried out. Typical distributions of velocity and temperature of the fluid inside the tanks are illustrated and studied in detail. The maximum temperature and standard temperature deviation in the storage tank were chosen to evaluate cooling effect and mixing effect, respectively. By comparing the synthesized chilling performances of the six different configurations, an optimal structure has been obtained. This research is helpful to improve the performance of cryogenic liquid storage system for space application. [ABSTRACT FROM AUTHOR]

The effects of glucocorticoid on lipid metabolism of broiler chicken ( Gallus gallus domesticus) skeletal muscle were investigated. Male Arbor Acres chickens (35 days old) were subjected to dexamethasone treatment for 3 days. We found that dexamethasone retards body growth while facilitating lipid accumulation. In M. pectoralis major (PM), dexamethasone increased the expression of glucocorticoid receptor (GR), fatty acid transport protein 1 (FATP1), heart fatty acid-binding protein (H-FABP) and long-chain acyl-CoA dehydrogenase (LCAD) mRNA and decreased the expression of liver carnitine palmitoyltransferase 1 (L-CPT1), adenosine-monophosphate-activated protein kinase (AMPK) α2 and lipoprotein lipase (LPL) mRNA. LPL activity was also decreased. In M. biceps femoris (BF), the levels of GR, FATP1 and L-CPT1 mRNA were increased. AMPKα (Thr172) phosphorylation and CTP1 activity of skeletal muscle were decreased by dexamethasone. In fed chickens, dexamethasone enhanced very low-density lipoprotein receptor (VLDLR) expression and AMPK activity in muscle, but it impaired the expression of LPL and L-CPT1 mRNA and LPL activity in PM and augmented the expression of GR, LPL, H-FABP, L-CPT1, LCAD and AMPKα2 mRNA in BF. Adipose triglyceride lipase (ATGL) protein expression was not affected by dexamethasone. In conclusion, in the fasting state, dexamethasone-induced-retarded fatty acid utilisation may be involved in the augmented intramyocellular lipid accumulation in both glycolytic (PM) and oxidative (BF) muscle tissues. In the fed state, dexamethasone promoted the transcriptional activity of genes related to lipid uptake and oxidation in muscles. Unmatched lipid uptake and utilisation are suggested to be involved in the augmented intramyocellular lipid accumulation. [ABSTRACT FROM AUTHOR]

Inclined silver nanorods (AgNRs) are highly anisotropic, with various applications in energy conversion, plasmonic and photonic devices, and sensing. So far, related studies have focused on the reflection or transmission, whereas studies on the diffraction and scattering from anisotropic AgNRs are still lacking. We investigate the anisotropic radiative properties of novel micro/nanoscale hybrid structures of inclined AgNRs deposited on compact disk (CD) gratings, which were fabricated with an oblique angle deposition technique. The reflectance of each diffraction peak and directional–hemispherical reflectance are characterized with a laser scatterometer and an integrating sphere, respectively, for both polarizations at a wavelength of 635 nm. The ordinary and extraordinary optical constants predicted from the effective medium theory (EMT) are incorporated into a rigorous coupled-wave analysis (RCWA) algorithm to estimate the diffraction efficiencies. The effect of scattering (mainly due to surface roughness) is also examined. The result shows that the orientation of the tilted nanorods with respect to the direction of grooves has a significant effect on both the energy distribution of the diffraction rays and the angular distribution of the scattered light for different polarizations. Such a hybrid structure may offer an alternative solution to engineering the radiative properties of a surface. [ABSTRACT FROM PUBLISHER]

The spatial distribution patterns of Polycyclic Aromatic Hydrocarbons (PAHs) in soil are important to regional environmental assessment. In this paper, the spatial structural features of sixteen prior PAH compounds in the topsoil of Tianjin area, as well as soil properties, were studied. Results shown that medium scale spatial autocorrelations were well revealed. Spherical models with sills could be used to fit all experimental variograms. The spatial structures of PAHs contents demonstrated significant anisotropy. Air precipitation caused by the combustion of coal was the key factor in the formation of the spatial structural patterns of PAHs in the topsoil of Tianjin area. [ABSTRACT FROM AUTHOR]

In the machining of mirror-like surfaces, a typical cutting depth of a few micrometers is common. With such a small depth of cut, chip formation takes place within individual grains of polycrystalline materials. In this article, orthogonal cutting of single copper crystals was performed in order to investigate the dependency of cutting deformation and surface quality on the crystallographic orientation of the substrate material. The experimental results show that the crystallographic orientation of the workpiece exerts a significant influence on the shear angle and the machined surface roughness. Cutting force variation with crystallographic orientation was analyzed on the basis of a microplasticity model. The trend in the variation of theoretical values of an effective Taylor factor (the shear strength) compares well with that of published experimental data on cutting forces. [ABSTRACT FROM AUTHOR]

Reports on the 2002 workshop on seeded x-ray free electron laser (FEL) at the National Synchrotron Light Source of the Brookhaven National Laboratory. Sponsors of the event; Properties of Self Amplified Spontaneous Emission FEL presented during the workshop.