在分销系统中,对库存补货策略进行科学管理与控制是一直是学者们研究的热点之一,学术界始终没有有效提高三个传统库存补货策略运作效率的有效方法.在两个传统补货策略(EB(echelon-based),TB(time-based))策略的基础上,从减少EB和TB策略...在分销系统中,对库存补货策略进行科学管理与控制是一直是学者们研究的热点之一,学术界始终没有有效提高三个传统库存补货策略运作效率的有效方法.在两个传统补货策略(EB(echelon-based),TB(time-based))策略的基础上,从减少EB和TB策略的极端情况角度,提出了混合策略1(HBl,Hybrid Based Policy1)和混合策略2(HB2,Hybrid Based Policy2),并将HB1和HB2的优点结合起来形成双混合策略(RH,Re-Hybrid Policy).数值试验表明,HB1、HB2对EB、TB的总成本费用比率有不同程度的改善,同时RH能有效改善HB1、HB2的总成本费用比率.展开更多
In order to investigate the effect of erbium (Er) on the microstructure of orthorhombic Ti2A1Nb-based alloys, four testing alloys were prepared by adding differ- ent contents of the rare earth metal Er to Ti-22A1-25...In order to investigate the effect of erbium (Er) on the microstructure of orthorhombic Ti2A1Nb-based alloys, four testing alloys were prepared by adding differ- ent contents of the rare earth metal Er to Ti-22A1-25Nb alloy and optical microscopy, X-ray diffraction, scanning electron microscopy, electron probe microanalysis, energy- dispersive spectrometry, and transmission electron microscopy were used. The results show that the addition of Er is capable of grain refining and the refinement effect is more obvious with increasing content of Er. The Er203 dispersoids formed by internal oxidation and A13Er com- pound particles are observed in Er-doped alloys and the number of Er precipitates is increased with increasing Er addition. It is likely that the solubility of Er in the Ti2A1Nb alloy is very low and Er precipitates tend to segregate at grain boundaries, which together with the surface activity of rare earth elements is supposed to decrease the prior B2 grain size of Ti-22A1-25Nb alloy effectively.展开更多
This paper discusses a physics-informed methodology aimed at reconstructing efficiently the fluid state of a system.Herein,the generation of an accurate reduced order model of twodimensional unsteady flows from data l...This paper discusses a physics-informed methodology aimed at reconstructing efficiently the fluid state of a system.Herein,the generation of an accurate reduced order model of twodimensional unsteady flows from data leverages on sparsity-promoting statistical learning techniques.The cornerstone of the approach is l_(1) regularised regression,resulting in sparselyconnected models where only the important quadratic interactions between modes are retained.The original dynamical behaviour is reproduced at low computational costs,as few quadratic interactions need to be evaluated.The approach has two key features.First,interactions are selected systematically as a solution of a convex optimisation problem and no a priori assumptions on the physics of the flow are required.Second,the presence of a regularisation term improves the predictive performance of the original model,generally affected by noise and poor data quality.Test cases are for two-dimensional lid-driven cavity flows,at three values of the Reynolds number for which the motion is chaotic and energy interactions are scattered across the spectrum.It is found that:(A)the sparsification generates models maintaining the original accuracy level but with a lower number of active coefficients;this becomes more pronounced for increasing Reynolds numbers suggesting that extension of these techniques to real-life flow configurations is possible;(B)sparse models maintain a good temporal stability for predictions.The methodology is ready for more complex applications without modifications of the underlying theory,and the integration into a cyberphysical model is feasible.展开更多
The paper presents the results of a comprehensive monitoring of the polygon: "Odessa Region, north-western part of the Black Sea" for the period 2009-2011. It is shown that most of the copper and nickel is brought ...The paper presents the results of a comprehensive monitoring of the polygon: "Odessa Region, north-western part of the Black Sea" for the period 2009-2011. It is shown that most of the copper and nickel is brought into the sea from the catchment area, and zinc and cadmium are mainly of the autochthonous origin. It is found that in 2010, after heavy rains, the area of bottom sediments contaminated by copper and nickel was increased. The main source of copper in the sea is vast vineyards.展开更多
AIM:To examine whether administration of lentinan,purifiedβ-1,3-glucan,can prolong survival in advanced gastric cancer patients receiving S-1-based chemotherapy.METHODS:Since 2004,78 patients with metastatic or recur...AIM:To examine whether administration of lentinan,purifiedβ-1,3-glucan,can prolong survival in advanced gastric cancer patients receiving S-1-based chemotherapy.METHODS:Since 2004,78 patients with metastatic or recurrent gastric cancer have received S-1-based chemotherapy as first-line treatment.Survival,side effects,and the ratio of granulocytes/lymphocytes(G/L ratio)were compared between 2 groups of patients who received chemo-immunotherapy using lentinan and chemotherapy alone.RESULTS:Median overall survival was significantly longer in the former group than in the latter group[689 d(95%CI:431-2339 d)vs 565 d(95%CI:323-662 d),P=0.0406].In addition,the G/L ratio in patients who received lentinan was maintained around or below 2,which was significantly lower than that in patients who received chemotherapy alone(P<0.001).CONCLUSION:Chemo-immunotherapy with lentinan offers a significant advantage over S-1-based chemotherapy alone in terms of survival in patients with advanced gastric cancer.展开更多
文摘在分销系统中,对库存补货策略进行科学管理与控制是一直是学者们研究的热点之一,学术界始终没有有效提高三个传统库存补货策略运作效率的有效方法.在两个传统补货策略(EB(echelon-based),TB(time-based))策略的基础上,从减少EB和TB策略的极端情况角度,提出了混合策略1(HBl,Hybrid Based Policy1)和混合策略2(HB2,Hybrid Based Policy2),并将HB1和HB2的优点结合起来形成双混合策略(RH,Re-Hybrid Policy).数值试验表明,HB1、HB2对EB、TB的总成本费用比率有不同程度的改善,同时RH能有效改善HB1、HB2的总成本费用比率.
基金financially supported by the Science and Technology Ministry of China to the National High Technology "863" Project (No. 2012AA062302)
文摘In order to investigate the effect of erbium (Er) on the microstructure of orthorhombic Ti2A1Nb-based alloys, four testing alloys were prepared by adding differ- ent contents of the rare earth metal Er to Ti-22A1-25Nb alloy and optical microscopy, X-ray diffraction, scanning electron microscopy, electron probe microanalysis, energy- dispersive spectrometry, and transmission electron microscopy were used. The results show that the addition of Er is capable of grain refining and the refinement effect is more obvious with increasing content of Er. The Er203 dispersoids formed by internal oxidation and A13Er com- pound particles are observed in Er-doped alloys and the number of Er precipitates is increased with increasing Er addition. It is likely that the solubility of Er in the Ti2A1Nb alloy is very low and Er precipitates tend to segregate at grain boundaries, which together with the surface activity of rare earth elements is supposed to decrease the prior B2 grain size of Ti-22A1-25Nb alloy effectively.
文摘This paper discusses a physics-informed methodology aimed at reconstructing efficiently the fluid state of a system.Herein,the generation of an accurate reduced order model of twodimensional unsteady flows from data leverages on sparsity-promoting statistical learning techniques.The cornerstone of the approach is l_(1) regularised regression,resulting in sparselyconnected models where only the important quadratic interactions between modes are retained.The original dynamical behaviour is reproduced at low computational costs,as few quadratic interactions need to be evaluated.The approach has two key features.First,interactions are selected systematically as a solution of a convex optimisation problem and no a priori assumptions on the physics of the flow are required.Second,the presence of a regularisation term improves the predictive performance of the original model,generally affected by noise and poor data quality.Test cases are for two-dimensional lid-driven cavity flows,at three values of the Reynolds number for which the motion is chaotic and energy interactions are scattered across the spectrum.It is found that:(A)the sparsification generates models maintaining the original accuracy level but with a lower number of active coefficients;this becomes more pronounced for increasing Reynolds numbers suggesting that extension of these techniques to real-life flow configurations is possible;(B)sparse models maintain a good temporal stability for predictions.The methodology is ready for more complex applications without modifications of the underlying theory,and the integration into a cyberphysical model is feasible.
文摘The paper presents the results of a comprehensive monitoring of the polygon: "Odessa Region, north-western part of the Black Sea" for the period 2009-2011. It is shown that most of the copper and nickel is brought into the sea from the catchment area, and zinc and cadmium are mainly of the autochthonous origin. It is found that in 2010, after heavy rains, the area of bottom sediments contaminated by copper and nickel was increased. The main source of copper in the sea is vast vineyards.
文摘AIM:To examine whether administration of lentinan,purifiedβ-1,3-glucan,can prolong survival in advanced gastric cancer patients receiving S-1-based chemotherapy.METHODS:Since 2004,78 patients with metastatic or recurrent gastric cancer have received S-1-based chemotherapy as first-line treatment.Survival,side effects,and the ratio of granulocytes/lymphocytes(G/L ratio)were compared between 2 groups of patients who received chemo-immunotherapy using lentinan and chemotherapy alone.RESULTS:Median overall survival was significantly longer in the former group than in the latter group[689 d(95%CI:431-2339 d)vs 565 d(95%CI:323-662 d),P=0.0406].In addition,the G/L ratio in patients who received lentinan was maintained around or below 2,which was significantly lower than that in patients who received chemotherapy alone(P<0.001).CONCLUSION:Chemo-immunotherapy with lentinan offers a significant advantage over S-1-based chemotherapy alone in terms of survival in patients with advanced gastric cancer.