Robust capacitated facility location model for acquisitions under uncertainty

We study a new robust formulation for strategic location and capacity planning considering potential company acquisitions under uncertainty. Long-term logistics network planning is among the most difficult decisions for supply-chain managers. While costs, demands, etc. may be known or estimated well for the short-term, their future development is uncertain and difficult to predict.A new model formulation for the robust capacitated facility location problem is presented to cope with uncertainty in planning. Minimizing the expectation of the relative regrets across scenarios over multiple periods is the objective. It is achieved by dynamically assigning multi-level production allocations, locations and capacity adjustments for uncertain parameter development over time. Considering acquisitions for profit maximization and its supply-chain impact is new as well as the simultaneous decision of capacity adjustment and facility location over time. The solution of the novel robust formulation provides a single setup where good results can be achieved for any realized scenario. Hence, the solution may not be optimal for one particular scenario but may be good, i.e. the highest expected profit to gain, for any highly probable future realization. We show that robust mixed-integer linear programming model achieves superior results to the deterministic configurations in exhaustive computational tests. This dynamic robust formulation allows the supply-chain to favorably adapt to acquisitions and uncertain developments of revenue, demand and costs and hence reduces the potential negative impacts of uncertainty on supply-chain operations.     

Logic programming to predict cell fate patterns and retrodict genotypes in organogenesis

Caenorhabditis elegans vulval development is a paradigm system for understanding cell differentiation in the process of organogenesis. Through temporal and spatial controls, the fate pattern of six cells is determined by the competition of the LET-23 and the Notch signalling pathways. Modelling cell fate determination in vulval development using state-based models, coupled with formal analysis techniques, has been established as a powerful approach in predicting the outcome of combinations of mutations. However, computing the outcomes of complex and highly concurrent models can become prohibitive. Here, we show how logic programs derived from state machines describing the differentiation of C. elegans vulval precursor cells can increase the speed of prediction by four orders of magnitude relative to previous approaches. Moreover, this increase in speed allows us to infer, or ‘retrodict’, compatible genomes from cell fate patterns. We exploit this technique to predict highly variable cell fate patterns resulting from dig-1 reduced-function mutations and let-23 mosaics. In addition to the new insights offered, we propose our technique as a platform for aiding the design and analysis of experimental data.     

中国电力行业CDM潜力分析

构建了一种能够评估我国清洁发展机制(clean development mechanism,CDM)项目潜力的分析评价模型,该模型由两个主要模型"能源环境系统的综合评价模型"和"CDM项目潜力最优分析模型"组成。以此模型为基础,分析评价了我国电力行业CDM的实施潜力。结果表明,我国电力行业未来CDM项目的潜力巨大,且对节能的效果也非常显著。     

Purification and Characterization of Aporphine Alkaloids from Leaves of Nelumbo nucifera Gaertn and Their Effects on Glucose Consumption in 3T3-L1 Adipocytes

Aporphine alkaloids from the leaves of Nelumbo nucifera Gaertn are substances of great interest because of their important pharmacological activities, particularly anti-diabetic, anti-obesity, anti-hyperlipidemic, anti-oxidant, and anti-HIV’s activities. In order to produce large amounts of pure alkaloid for research purposes, a novel method using high-speed counter-current chromatography (HSCCC) was developed. Without any initial cleanup steps, four main aporphine alkaloids, including 2-hydroxy-1-methoxyaporphine, pronuciferine, nuciferine and roemerine were successfully purified from the crude extract by HSCCC in one step. The separation was performed with a simple two-phase solvent system composed of n-hexane-ethyl acetate-methanol-acetonitrile-water (5:3:3:2.5:5, v/v/v/v/v). In each operation, 100 mg crude extracts was separated and yielded 6.3 mg of 2-hydroxy-1-methoxyaporphine (95.1% purity), 1.1 mg of pronuciferine (96.8% purity), 8.5 mg of nuciferine (98.9% purity), and 2.7 mg of roemerine (97.4%) respectively. The chemical structure of four aporphine alkaloids are identified by means of electrospray ionization MS (ESI-MS) and nuclear magnetic resonance (NMR) analysis. Moreover, the effects of four separated aporphine alkaloids on insulin-stimulated glucose consumption were examined in 3T3-L1 adipocytes. The results showed that 2-hydroxy-1-methoxyaporphine and pronuciferine increased the glucose consumption significantly as rosiglitazone did.     

缺陷管道适用性评价技术研究进展

总结了近年来缺陷管道适用性评价技术的研究情况,随着断裂力学与计算机软件技术的不断发展,缺陷管道适用性评价技术也逐渐趋于完善。建立科学的适用性和完整性评价技术体系对我国油气管道的安全长期运行有着重要的意义。     

Optimization of Improvable Flows by combining BAT Analysis and process simulation

This paper proposes a methodology to improve the sustainability of industrial processes combining two tools: BAT Analysis and process simulation. Both tools are jointly applied to identify the IF of the analyzed process, so that the most appropriate candidate techniques from an inventory can be selected. The selected alternatives are tested in different scenarios that are evaluated using simulation, which would determine the configuration that best improves the sustainability of the process. The combination of both tools in an integrated methodology will help decision makers to select the most sustainable configuration for a given process. The methodology is validated in a case study: a hydrogen production plant. After analysing several scenarios where different candidate techniques are implemented, results show that the IF identified can be highly improved when the appropriate combination of BAT is applied.     

Magic Angle Spinning NMR of Macromolecular and Supramolecular Systems

Sideband patterns in single quantum and double quantum magic angle spinning NMR spectra are reviewed. Their use in elucidating non-covalent interactions, such as hydrogen bonds or pi-pi stacking, is demonstrated by studies of supramolecular systems of current interest. Moreover, the effects of local and collective motions are illustrated by examples from supramolecular and macromolecular science.     

Evaluating techniques for redirecting turbine wakes using SOWFA

Wind plant control is an active field of research in which controllers are developed that seek to maximize overall wind-plant performance in terms of power production, turbine structural loads, or both. Such control strategies are often different from those that are optimal for an individual turbine. One type of wind-plant control method is to redirect the wakes of upstream turbines so that they avoid downstream turbines. In this paper, we investigate several possible methods for redirecting turbine wakes, including some existing and some novel approaches. The methods are compared in terms of their ability to redirect turbine wakes and their effects on turbine power capture and structural loads using the high-fidelity wind plant simulation tool Simulator for On/Offshore Wind Farm Applications (SOWFA).     

Electronic structure and ferromagnetism of Fe11NiSi4, Fe11CoSi4, Fe11CrSi4 and Fe3Si from first principles

Based on the density functional theory (DFT), the plane-wave pseudopotential method was used to calculate structural stabilities, electronic structures, and ferromagnetism of Fe₃Si, Fe₁₁NiSi₄, Fe₁₁CoSi₄ and Fe₁₁CrSi₄ intermetallic compound. This study showed that the Fe₁₁NiSi₄ and Fe₁₁CrSi₄ phase are more stable than Fe₃Si phase, especially Fe₁₁NiSi₄, but decreased with Fe₁₁CoSi₄ phase. Calculating the density of states and the Mulliken electronic populations showed that Fe₁₁NiSi₄ had the highest structural stability because of its Fermi level, which was close to the bottom of the pseudo-gap. Fe₁₁NiSi₄ also had the largest Mulliken population, which increased the metallic bonding of the alloying system. The total magnetic moments of Fe₁₁NiSi₄, Fe₁₁CoSi₄ and Fe₁₁CrSi₄ were 20.04μ_B, 19.98μ_B, and 18.81μ_B, respectively. These magnetic moments mainly originated from the 3d spin polarization of Fe and those of additional atoms.     

Generalized eigenvalue minimization for uncertain first-order plus time-delay processes

This paper shows how to apply generalized eigenvalue minimization to processes that can be described by a first-order plus time-delay model with uncertain gain, time constant and delay. An algorithm to transform the uncertain first-order plus time delay model into a state-space model with uncertainty polyhedron is firstly described. The accuracy of the transformation is studied using numerical examples. Then, the uncertainty polyhedron is rewritten as a linear-matrix-inequality constraint and generalized eigenvalue minimization is adopted to calculate a feedback control law. Case studies show that even if uncertainties associated with the first-order plus time delay model are significant, a stable feedback control law can be found. The proposed control is tested by comparing with a robust internal model control. It is also tested by applying it to the temperature control of air-handing units.