Developing a process re-engineering-oriented organizational change exploratory simulation system (PROCESS)

In the past two decades, business process re-engineering (BPR) and organizational restructuring (OR) have been two of the most popular approaches to improving the efficiency and the effectiveness of an organization. However, a review of the relevant literature reveals that the two approaches have been studied in isolation. The theoretical gap in academic research is also reflected in practice. The present paper therefore proposes a customer-oriented and process-focused two-stage framework, entitled the ‘process re-engineering-oriented organizational change exploratory simulation system’ (‘PROCESS’), to address these theoretical deficiencies. Two key concepts are introduced in this two-stage framework. The first is the ‘process module’ (PM), which indicates a set of common sequential activities that can be grouped as a subunit of a business process. The second is the ‘macro-process’ (MP), which indicates that a set of business processes have similar characteristics or functions. The two concepts serve as ‘stepping stones’ between BPR and OR. Based on these two concepts, the decision rules and the mathematical/simulation model can be developed under this two-stage framework. The paper then presents a case study to demonstrate the effectiveness of the ‘PROCESS’.     

A fuzzy goal programming approach for green supply chain optimisation under activity-based costing and performance evaluation with a value-chain structure

Supply chain operation with sustainable consideration has become an increasingly important issue in recent years. However, the decision framework with integrated costing and performance evaluation for green supply chain (GSC) has not been well developed so far in the literature. For this reason, this paper is aimed to propose a fuzzy goal programming (FGP) approach that integrates activity-based costing (ABC) and performance evaluation in a value-chain structure for optimal GSC supplier selection and flow allocation. The FGP approach is particularly suitable for such a decision model which includes flexible goals, financial and non-financial measures, quantitative and qualitative methods, multi-layer structure, multiple criteria, multiple objectives, and multiple strategies. An activity-based example of structural GSC with relevant costs and performances is presented for computing the composite performance indices of the GSC suppliers. A green supply chain of a mobile phone is used as an illustrative case. Several objective structures and their results are compared. The sensitivity analyses show that pure maximisation of financial profit can achieve the highest profit level, which also has the largest Euclidean distance to the multiple aspiration goals. In order to determine the final objective structure, an analytic hierarchy process (AHP) is used. This paper provides a new approach to assess and control a complex GSC based on value-chain activities, and obtain a more precise solution. The establishment of this GSC model not only helps decision-makers to monitor GSC comprehensive performance but also can facilitate further improvement and development of GSC management.     

On monitoring of multiple non-linear profiles

Most state-of-the-art profile monitoring methods involve studies of one profile. However, a process may contain several sensors or probes that generate multiple profiles over time. Quality characteristics presented in multiple profiles may be related multiple aspects of product or process quality. Existing charting methods for simultaneous monitoring of each multiple profile may result in high false alarm rates. Or worse, they cannot correctly detect potential relationship changes among profiles. In this study, we propose two approaches to detect process shifts in multiple non-linear profiles. A simulation study was conducted to evaluate the performance of the proposed approaches in terms of average run length under different process shift scenarios. Pros and cons of the proposed methods are discussed. A guideline for choosing the proposed methods is introduced. In addition, a hybrid method combining the salient points of both approaches is explored. Finally, a real-world data-set from a vulcanisation process is used to demonstrate the implementation of the proposed methods.     

LQG/LTR loop shaping design with an application to position control

Abstract

In contrast to the conventional LQG method using calculus of variations, this paper presents an alternative approach based on operator theory and spectrum factorization. This approach, which works toward transfer function domain, has merits in its simple and straightforward development. The novelty of this method is not the results achieved, but rather in their derivation. A loop shaping design procedure which incorporates the classical loop shaping into LQG/LTR synthesis is developed such that the robustness properties of the optimal full state feedback are guaranteed at both the plant input and the plant output. The design procedure is applied to a position controller design in a servo system, and the performance is evaluated by a digital signal processor, the TMS320C30. Experimental results have shown effectiveness of this design method.     

Performance analysis of a separate address/data bus multiprocessor system

Abstract

This paper presents a performance model of a special shared bus multiprocessor system, that features: (1) separate address‐bus and data‐bus with split transaction, pipelined cycle; (2) two‐level cache structure; and (3) multiple main memory and I/O modules. Accessing conflicts in these subsystems, maintaining shared data and DMA transfer between memory and I/O subsystems are also considered in the model. The representation for the complex behavior of a whole multiprocessor system distinguishes the model from others that present only one major subsystem. The performance model can be used not only to assist in evaluating the architectural design of aparticular system, but also directly utilized to identify subsystem bottlenecks and their causes in order to make performance improvements. Results show that: (1) the values of some key design parameters, such as cache line size and data‐bus width that yield the best throughput, are dependent on the performance of subsystems; (2) choosing the data‐bus width at one‐half of cache line size can achieve the lowest access time in the shared bus; (3) using cache‐to‐cache transfer protocol may prevent performance degradation caused by maintaining shared data; and (4) the activity of DMA transfer may significantly affect system throughput and should be included in a performance model of multiprocessor systems.     

Numerical simulation and optimization of WC-SS420 induction brazing process

Tungsten carbide (WC) is a very hard, brittle, and relatively expensive cermet. It is often joined to more economical material, such as martensitic 420 stainless steel (SS420), to form a hybrid cutting tool stock. This article summarizes a study on the optimization of an induction brazing process joining these two materials using BAg-22 as filler metal. This study uses an integrated approach consisting of finite element analysis (FEA) modeling and experimental verifications. The thermal behaviors and the metallurgical transitions during the brazing cycles of WC-BAg22-SS420 joints are studied. This study investigated process and metallurgical issues due to mismatches in thermal expansion coefficient, thermal conductivity, and electromagnetic permeability. Using the optimum process parameters derived from simulation, joint strengths exceeding 370?±?40?MPa for shear were obtained. The hardness of WC was unaffected by the brazing heat. However, softening in the SS420 next to the fusion interface was constantly observed in the experiments. The FEA modeling results demonstrated that using a controlled heating and cooling process schedule was effective in mitigating this softening phenomenon. Experimental verification of this mitigation method is currently under study.     

Comparison of the Solubility and Dissolution Rate Between Gliclazide Solid Complex and Its Nanospheres

ABSTRACT

The solid complex of gliclazide and β-cyclodextrin was prepared by neutralization method and the precipitation solvent evaporation method was used to prepare gliclazide nanospheres. Fourier-transform infrared spectroscopy and differential scanning calorimetry were used to examine whether gliclazide solid complex and gliclazide nanospheres were successfully formed in this study. The dissolution rate of gliclazide from its nanospheres was faster than its solid complex and pure drug. The morphology of particles for nanospheres showed no crystal character of gliclazide. In summary, the results indicate that nanotechnology provides better effects in solubility and dissolution rate of gliclazide than neutralization method.     

The structure‐property relationship of novolac cured epoxy resin/clay nanocomposites

Intercalated or exfoliated novolac cured epoxy resin nanocomposites were prepared with two different kinds of layered silicates – montmorillonite (PK‐802) and nontronite (PK‐805). The bifunctional modifiers (PI/BEN or MI/BEN) are used to modify the clays for improvement of the properties of polymer where benzalkonium chloride (BEN) acts as a compatibilizing agent and 2‐phenylimidazole (PI) or 2‐methylimidazole (MI) as the accelerators. Both the compatibilizer and accelerator are simultaneously intercalated into the gallery space of pure clays to form the modified clay. The novolac cured epoxy nanocomposites are prepared with these modified clays by crosslinking polymerization reaction. The properties of novolac cured epoxy/clay nanocomposites were characterized by wide‐angle X‐ray diffraction (WAXD), thermo‐gravimetric analysis (TGA), dynamic mechanical analysis (DMA), and transmission electron microscopy (TEM) methods. According to the measurement, these novolac cured epoxy‐clay nanocomposites have been shown the significant improvement in the thermal, mechanical, and barrier properties that may be applied to make printed circuit board. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

Plasma oxidation of Al thin films on Si substrates

In this study, Al thin films deposited on silicon wafers by direct current magnetron sputtering were oxidized under radio frequency 13.56 MHz O₂ plasma at temperatures up to 550 °C. During oxidation, plasma powers as well as oxidation temperature and time were varied to investigate the oxidation behavior of the Al films. X-ray photoelectron spectroscopy and Auger electron spectroscopy results show that the apparent alumina could be observed after O₂ plasma treatment with powers above 200 W as well as at temperatures above 250 °C. However, no alumina increment could be discerned after individual either heat treatment at 550 °C or plasma treatment at room temperature. The thickness of alumina layers increased remarkably with plasma power and could reach about 60 nm when undergone 400 W O₂ plasma treatment at 550 °C for 2 h. Moreover, the thickness of alumina increased parabolically with time during plasma oxidation aided by thermal treatment. The deduced activation energy of such plasma oxidation was 19.1 ± 0.5 kJ/mol.     

Evaluation of microstructures and mechanical properties of diamond like carbon films deposited by filtered cathodic arc plasma

Diamond-like carbon (DLC) films were deposited by a cathodic arc plasma evaporation (CAPD) process, using a mechanical shield filter combined with a magnetic filter with enhanced arc structure at substrate-bias voltage ranging from − 50 to − 300 V. The film characteristics were investigated using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and high-resolution transmission electron microscopy (HRTEM). The mechanical properties were investigated by using a nanoindentation tester, scratch test and ball on disc wear test. The Raman spectra of the films showed that the wavenumber ranging from 900 to 1800 cm^− 1 could be deconvoluted into 1140 cm^− 1, D band and G band. The bias caused a significant effect on the sp³ content which was increased with the decreasing of I_D/I_G ratio. The XPS spectra data of the films which were etched by H⁺ plasma indicated the sp³ content are higher than those of the as-deposited DLC films. This implied that there is a sp²-rich layer present on the surface of the as-deposited DLC films. The nanoindentation hardness increased as the maximum load increased. A 380 nm thick and well adhered DLC film was successfully deposited on WC-Co substrate above a Ti interlayer. The adhesion critical load of the DLC films was about 33 N. The results of the wear tests demonstrated that the friction coefficient of the DLC films was between 0.12 and 0.2.