On the treatment of boundary conditions by the method of artificial parameters

A procedure to deal with various boundary conditions in the Rayleigh-Ritz method is discussed herein, namely, the method of artificial parameters. The method is then applied to solve a simple string problem; results obtained compare very nicely with exact solutions.     

Molecular layer deposition of an organic-based magnetic semiconducting laminate

Organic-based magnets are intriguing materials with unique magnetic and electronic properties that can be tailored by chemical methodology. By using molecular layer deposition (MLD), we demonstrate the thin film fabrication of V[TCNE: tetracyanoethylene](x), of the first known room temperature organic-based magnet. The resulting films exhibit improvement in surface morphology, larger coercivity (80 Oe), and higher Curie temperature/thermal stability (up to 400 K). Recently, the MLD method has been widely studied to implement fine control of organic film growth for various applications. This work broadens its application to magnetic and charge transfer materials and opens new opportunities for metal-organic hybrid material development and their applications in various multilayer film device structures. Finally, we demonstrate the applicability of the multilayer V[TCNE](x) as a spin injector combining LSMO, an standard inorganic magnetic semiconductor, for spintronics applications.     

IEEE802．15．4的MAC协议实现

IEEE802．15．4协议是无线传感网中多采用的一种低速率、低功耗、低成本的无线通信协议。Imote2是Intel公司推出的高集成度的无线传感器平台。文中介绍了Imote2平台以及IPF．FS02．15．4协议,及网络驱动程序的体系结构,给出了实现IEEE802．15．4的MAC协议过程中的关键函数,还对MAC协议实现中的中断服务响应以及时钟等关键问题进行了描述。并分别对节点的工作性能及组网时节点的性能及损耗进行了测试,给出了系统的性能。结果显示,该种实现方法有效地保证了系统的性能并且可以达到无线传感网组网需求。     

Muscle Wasting in Chronic Kidney Disease: Mechanism and Clinical Implications—A Narrative Review

Muscle wasting, known to develop in patients with chronic kidney disease (CKD), is a deleterious consequence of numerous complications associated with deteriorated renal function. Muscle wasting in CKD mainly involves dysregulated muscle protein metabolism and impaired muscle cell regeneration. In this narrative review, we discuss the cardinal role of the insulin-like growth factor 1 and myostatin signaling pathways, which have been extensively investigated using animal and human studies, as well as the emerging concepts in microRNA- and gut microbiota-mediated regulation of muscle mass and myogenesis. To ameliorate muscle loss, therapeutic strategies, including nutritional support, exercise programs, pharmacological interventions, and physical modalities, are being increasingly developed based on advances in understanding its underlying pathophysiology.     

Fabrication of Pb1‐xSnxTe/PbTe heterojunctions by liquid phase epitaxy

Abstract

Pb_1‐x Sn _x Te epitaxial layers were successfully grown on PbTe substrates by liquid phase epitaxy (LPE) technique. The compositions and surface morphology of the epitaxial Pb_1‐x Sn _x Te layers were controlled in the LPE growth, and p‐Pb_1‐x Sn _x Te/n‐PbTe heterodiodes with a good junction‐perfection factor were made.     

Data envelopment analysis in resource allocation: An application to forest management

This paper discusses the resource allocation problem for not-for-profit organizations that have control over several production units of similar functions. A case of budget allocation among the subdistricts of a forest district in Taiwan is exemplified to illustrate the idea. The model proposed is a nonlinear fractional program superimposed upon the data envelopment analysis framework. This nonlinear fractional program can be transformed to a model similar to the generalized linear program and solved by a type of decomposition method. Within prespecified ranges, the district office searches for ways of allocating a fixed amount of budget to its subdistricts to result in a higher aggregate efficiency score. Wider ranges allow for more flexibility in allocating budget; consequently, higher aggregate efficiency scores are experienced. Since this method is more objective, it is more persuasive to the subdistricts in allocating resources.     

Volume Shrinkage Induced by Interfacial Reaction in Micro-Ni/Sn/Ni Joints

Experiments are carried out to measure the volume shrinkage during solid-state reaction in micro-joints for three-dimensional integrated circuit applications. Surface profilometer is employed to measure the volume shrinkage for the reaction between Ni and Sn. The shrinkage is correlated with the microstructural evolution during the reaction. It is found that the volume shrinkage is released through both joint height reduction and void formation. The resulting internal stress and the void formation might post potential reliability issues.     

Spark Parameter Monitoring Feedback System for Preparation of Nanosilver Colloid in EDM

This study developed a system monitoring the electric discharge machine's (EDM) discharge energy and success rate to replace conventional oscilloscope observation. By using logic circuit, the signals are transmitted to the PC monitoring platform in order to display the discharge success times, discharge success rate, and electrode's consumption energy. The advantage of the proposed system is the capability to observe real-time discharges and record the experimental conditions, as well as optimize the discharge parameter settings. The experimental results suggest that, in the preparation of nanosilver colloid, the cost-performance of T_on–T_off at 10–100 µs is the optimal setting. The monitoring system also can take advantage of the discharge success rate to control the energy consumption of the electrode to obtain the standardization of products. The results suggest that, while discharge success rate, electrode's weight loss and wavelength of the absorption peak are considerably accurate, but concentration accuracy is relatively poor. The discharge success rate monitoring system is an innovative method that can help to realize electric discharge processing, optimize product quality, and it may be a powerful processing tool in the future.     

Ink drop filling by a slot coating die for an electrowetting display panel

Ink drops have to be filled into the square cells for an electrowetting display panel. Several ink solutions such as dodecane, tetradecane, and hexadecane were used as test liquids. These fluids have viscosities less than 4 mPas and surface tensions between 23.3 and 26 mN/m and contact angles less than 50°. A slot coating die was employed to deliver these liquids to fill up the square cells. The effects of several parameters such as coating thickness and coating speed were examined. Operating windows inside which the stable filling is possible could be found for these liquids. Several defects were observed outside the operating windows. A flow visualization technique was applied to observe the fluid motion in the coating bead region, particularly the movements of upstream and downstream menisci, the mechanism of liquid filling was discussed.