Elastodynamic response of bonded solids using the method of eigenfunction expansion

In this article, the orthogonality of eigenfunctions corresponding to the vibrations of perfectly bonded solids under complex homogeneous boundary conditions is proved in detail. Then, the exact transient response solution of such bonded solids is constructed using the eigenfunction expansion method (EEM). Furthermore, the transient response of bonded circular plates is taken as an example to illustrate the application of the general theory. The numerically evaluated analytic solution is shown to be in good agreement with that obtained by the finite element method (FEM).     

Utility-Based Pricing,Timing and Hedging of an American Call Option Under an Incomplete Market with Partial Information

This paper studies the pricing, timing and hedging of an American call option written on a non-tradable asset whose mean appreciation rate is not observable but is known to be a Gaussian random variable. Our goal is to analyze the effects of the partial information on investment in the American option under an incomplete market. The objective of the option holder is to maximize the expected discounted utility of consumption over an infinite lifetime. Thanks to consumption utility-based indifference pricing principal, stochastic control and filtering theory, under CARA utility, we derive the value and the exercise time of the American call option, which are determined by a semi-closed-form solution of a free-boundary PDE problem with a finite time horizon. We provide numerical results by finite difference methods and compare the results with those under a fully observable case. Numerical calculations demonstrate that partial information leads to a significant loss of the implied value of the American call option. This loss increases with the uncertainty of the mean appreciation rate. If the option holder is risk-averse enough, a growth of the systematic/idiosyncratic risk will increase/decrease the implied option value and the option is exercised later/sooner. Whether a stronger positive correlation between the tradable asset and the non-tradable underlying asset increases the option value and the information value depends on the risk attitude of the option holder. On the contrary, a stronger negative correlation will definitely make the option and the information more valuable. In addition, explicit expressions of the utility-based pricing for a perpetual American call are presented if the tradable risky asset is perfectly correlated with the underlying asset.     

邯钢烧结配矿结构优化实践

通过研究含铁料基础性能,分析各种配矿结构对烧结过程的影响规律,确定主流矿种及其合理区间,在此基础上,结合综合成本、有害元素、资源库存等因素进行动态优化调整,贯彻稳硅控铝思路,根据生产需要及主流料资源制定更加合理的配矿结构。     

含微细颗粒的挥发性有机废气综合治理技术研究开发

工业的发展，带来了很多丰闷关的环境污染问题。挥发性有机物（VOcs）是常见的污染物，对环境、动植物的生长及人类健康造成了极大的危害，因此越来越受到世界各国的重视，许多发达国家都颁布了相应的法令，限制VOCs的排放。含微细颗粒的挥发性有机废气由于多种物质成份并存，特别是橡胶行业炼胶废气一直是环保治理的难点。我们提出采用“预处理除油装置＋活性炭流动床吸附＋布袋除尘器＋活性炭固定床吸附装置”的处理方式，能有效治理这类废气，尤其是针对橡胶行业炼胶废气，具有处理效率高、运行稳定、运行费用低、操作简便等特点。     

Quantum discord for two-qubit systems in the Bloch channel: effects of longitudinal and transversal relaxation times

Quantum discord is studied for two-qubit systems with different settings under the influence of the Bloch channel which is characterized by the longitudinal and transversal relaxation times and the environmental temperature. The relaxation of the quantum discord strongly depends on the ratio of the two relaxation times and the environmental temperature. It is found that the ratio of the quantum discord to the total correlation becomes finite or zero asymptotically, depending on the ratio of the relaxation times and the system setting. Furthermore, the optimal setting for sharing the quantum discord is discussed for given environmental temperature and ratio of the relaxation times.     

Development of a noble aluminum-pigmented metallic polymer: Recommendations for visible flow and weld line mitigation

We investigated the appearance of flow and weld lines when metallic pigments are used in polymer blends and how such lines can be eliminated by improving the pigment particle shape and optimizing pigment loading. Acrylonitrile butadiene styrene copolymer and two types of aluminum flakes, lamellar and three-dimensional (3D), were blended in a twin-screw extruder with a screw diameter of 25 mm. The temperatures from the hopper to the nozzle were 140, 180, 220, 220, 220, 220, and 220°C. Weld and flow lines were observed using field-emission scanning electron microscopy and energy dispersive X-ray spectroscopy of specially manufactured injection specimens. In the flow line region, traditional lamellar flakes were randomly oriented, while 3D flakes exhibited a distinct and stable orientation. Based on these observations, flow and weld lines in a finished metal/polymer blend can be minimized by using 3D metal particles in place of lamellar flakes. We also investigated the effects of aluminum flake loading on weld and flow line visibility. At low loading, weld lines were clearly visible due to the lack of pigmentation in the front of the polymer flow. Conversely, high loading resulted in relatively high concentrations of pigment near the weld line area, reducing weld line visibility. These findings suggest that there is an optimum metal loading level where the visibility of flow and weld lines is minimized.     

Development of insertion-type peristalsis pump using pneumatic artificial muscles

This study aims to develop a new type of peristaltic pump that transports high-viscosity and solid–liquid mixture fluids. Pumps capable of transporting such fluids are essential in various situations such as factory transportation, outdoors, and emergencies. These fluids are conventionally transported by positive-displacement and rotodynamic pumps. However, solid–liquid fluids could collide with the impeller of the rotodynamic pump and thereby damage the pump, whereas the positive-displacement pump must be sufficiently large to apply high pressure to the transported fluid. A small pump that can transport these fluids would save factory space and enable outdoor applications such as dredging operations. Thus, we adopted earthworm peristalsis as a model mechanism of fluid transport within a standard plumbing infrastructure. The insertion-type peristaltic pump developed in this study uses an artificial rubber muscle to achieve an earthworm-like mechanism. The capability and energy efficiency of the mechanism is evaluated in water transportation experiments.     

基于数值模拟分析的土石坝泄洪与蓄水过程安全预测

针对土石坝在泄洪及蓄水过程中较易诱发影响其稳定性的突发事件的部分因素,利用数值分析法模拟了其作用机理,找出了一些可利用的规律。据此,可在不知泄洪或蓄水可能在某一状态会带来不良后果的情况下去预测坝体在水位达到一定高度时的破坏状态,旨在为工程提供一定的加固依据,达到防灾减灾的目的。同时,利用有限元分析方法分析可能的危险状态下坝体内部系统作用状态,从理论上进一步验证在该状态下的坝体稳定状况。     

溶液法合成的功能无机材料氧化镍对钙钛矿太阳能电池光电性能的影响

功能无机材料氧化镍 （NiO_x） 作为钙钛矿太阳能电池中最有前途的空穴传输材料之一，其有着高空穴迁移率、良好的稳定性、易于加工以及适合的费米能级等优点。但是，由于 NiO_x自身固有电导率低，Ni空位的电离能相当大，未掺杂的 NiO_x中空穴密度受到很大限制，加上孔洞的积累增加了载流子复合的可能，从而降低了有效的电荷收集。因此，优化 NiO_x薄膜的成膜质量是解决上述问题的关键。本文通过溶液法使用乙二醇甲醚（MEA）、乙醇（EA）和去离子水作为溶液，分别制备了 DME-NiO_x、EA-NiO_x 和 NCs-NiO_x 薄膜，并在浓度调节范围内对基于 NiO_x的钙钛矿器件进行优化，最终得到了光电转化效率 （PCE） 为 18.50%，开路电压 (V_oc) 为 1.034 V，短路电流 (J_sc) 为 22.94 mA/cm²，填充因子 （FF） 为 78% ...