A performance-based approach to project assignment and performance evaluation

Project assignment and performance evaluation have been addressed as two important and separate research issues in project management. This paper develops a new performance-based approach for integrating the project assignment and the performance evaluation processes in a project-based organization. An objective-oriented preference-based assignment process is developed to assign a project to a project manager. An optimal project assignment model is developed to maximize the total weighted contribution value of all new projects to the organizational objectives. An efficiency-based evaluation process is developed using data envelopment analysis to measure the relative performance efficiency of the completed projects and of the project managers. The approach provides a proactive mechanism for facilitating objective-focused management of projects. The outcomes of an empirical study conducted provide managerial insights in assigning projects to project managers and in evaluating the performance efficiency of both projects and project managers.     

Adjustment behaviour of capital structure over the business cycles: evidence from the construction industry of Taiwan

Prior studies have found that firms may deviate from the target capital structure in the short run and adjust towards the target in the long run. However, little attention has been given to the adjustment behaviour of capital structure in the construction industry over the business cycles, in particular within the context of emerging markets. The partial adjustment model with the GMM (i.e. generalized method of moments) estimation is used to examine the adjustment behaviour of capital structure in the construction industry within the context of Taiwan during the period 1982 to 2007. The results suggest that, first, the average rate of adjustment is 26.3% of the adjustment gap between the target debt ratios and the previous debt ratios for firms in the construction industry of Taiwan. However, the average rate of adjustment towards the target debt ratios has slowed down after the Asian financial crisis of 1997. Secondly, firms with the financial constraint of over‐leverage relative to the target debt ratios have lower debt ratios than those firms with the financial constraint of under‐leverage. In addition, the difference in debt ratios between firms with the financial constraint of over‐leverage and under‐leverage has become narrower after the Asian financial crisis. Lastly, the findings suggest that macroeconomic conditions do not have a significant, negative effect on debt ratios.     

Physical properties of epoxy resin self‐reinforced with organic rigid‐rod compounds

In this study, nanoscale organic rigid‐rod compounds were utilized as self‐reinforcing composites to enhance the physical properties of an epoxy resin diglycidylether of bisphenol A (DGEBA). First, DGEBA was used to react with an aromatic diisocyanate of methylene diphenyl isocyanate (MDI) to form an urethane linkage. Next, four different organic rigid‐rod compounds including 4′‐hydroxyphenyl‐4‐hydroxybenzoate, phenyl 4‐hydroxybenzoate, 4,4′‐isopropylidenediphenol, and 2‐naphthol were incorporated to react individually with the remaining isocyanate groups of the MDI units after the previous step. Finally, the four different rigid‐rod‐modified DGEBA systems were examined using nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, scanning electric microscopy, and mechanical property analyses. Each of the four rigid‐rod‐reinforced DGEBA systems exhibited greatly improved mechanical properties, e.g., higher tensile strengths and fracture energies. POLYM. ENG. SCI., 47:1281–1288, 2007. © 2007 Society of Plastics Engineers     

Evaluation of a haptics-based virtual reality temporal bone simulator for anatomy and surgery training

Introduction

Virtual reality simulation training may improve knowledge of anatomy and surgical skills. We evaluated a 3-dimensional, haptic, virtual reality temporal bone simulator for dissection training.

Methods

The subjects were 7 otolaryngology residents (3 training sessions each) and 7 medical students (1 training session each). The virtual reality temporal bone simulation station included a computer with software that was linked to a force-feedback hand stylus, and the system recorded performance and collisions with vital anatomic structures. Subjects performed virtual reality dissections and completed questionnaires after the training sessions.

Results

Residents and students had favorable responses to most questions of the technology acceptance model (TAM) questionnaire. The average TAM scores were above neutral for residents and medical students in all domains, and the average TAM score for residents was significantly higher for the usefulness domain and lower for the playful domain than students. The average satisfaction questionnaire for residents showed that residents had greater overall satisfaction with cadaver temporal bone dissection training than training with the virtual reality simulator or plastic temporal bone. For medical students, the average comprehension score was significantly increased from before to after training for all anatomic structures. Medical students had significantly more collisions with the dura than residents. The residents had similar mean performance scores after the first and third training sessions for all dissection procedures.

Discussion

The virtual reality temporal bone simulator provided satisfactory training for otolaryngology residents and medical students.     

Structure-activity relationship studies of 3-aroylindoles as potent antimitotic agents

The concise synthesis and structure-activity relationship (SAR) studies of 3-aroylindoles were carried out in an effort to improve the potency and solubility of anticancer drug candidate BPR0L075 (8) by exploring structure modifications through three regimens: substitution of the B ring, at the N1 position, and of the 3-carbonyl linker. The SAR information revealed that the methoxy group of the B ring could be replaced with an electron-donating group such as methyl (in compound 9) or N,N-dimethylamino (in compound 13) while retaining both strong cytotoxic and antitubulin activities. The introduction of amide (compounds 30-33) and carbamate (compounds 34-37) functionalities at the N1 position of 8 gave analogues with potent antiproliferative activities. The cytotoxic potency of 8 was improved by replacing the carbonyl group with sulfide (compound 41) or oxygen (compound 43), indicating that the carbonyl moiety is important but not essential. The N,N-dimethylamino derivative 13 not only displayed potent cytotoxicity and antitubulin activity, but also showed a markedly improved physicochemical profile relative to the parent compound.     

Preparation and properties of heterocyclically conjugated poly(3‐hexylthiophene)–clay nanocomposite materials

A series of heterocyclically conjugated polymer–clay nanocomposite (PCN) materials that consisted of organic poly(3‐hexylthiophene) (P3HT) and inorganic montmorillonite (MMT) clay platelets were prepared by in situ oxidative polymerization with FeCl₃ as an oxidant. The as‐synthesized PCN materials were characterized by Fourier transform infrared (FTIR) spectroscopy, wide‐angle powder X‐ray diffraction (WAXRD), and transmission electron microscopy (TEM). The effects of the material composition on the anticorrosion, gas barrier, thermal stability, flammability, mechanical strength, and electrical conductivity properties of the P3HT and PCN materials were studied by electrochemical corrosion measurements, gas‐permeability analysis (GPA), thermogrametric analysis (TGA), limiting oxygen index (LOI) measurements, dynamic mechanical analysis (DMA), and a four‐point probe technique, respectively. The molecular weights of extracted and bulk P3HT were determined by gel permeation chromatography (GPC) with THF as an eluant. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3438–3446, 2004     

Estimating discharge in gravel‐bed river using non‐contact ground‐penetrating and surface‐velocity radars

Discharge measurement is a critical task for gravel‐bed channels. Under high‐flow conditions, the elevation of the riverbed changes significantly by intensive torrential flow. The stage–discharge relations commonly used for stream discharge estimation may no longer be adequate. The contact‐type velocity measuring is also subject to measurement errors and/or instrument failures by the high‐flow velocities, driftwood, stumps, and debris. This study developed a new real‐time method to estimate river discharge in gravel‐bed channels. A systematic measuring technology combining ground‐penetrating radar and surface‐velocity radar was employed. The rating curves representing the relations of water surface velocity to the channel cross‐sectional mean velocity and flow area were established. Stream discharge was then deduced from the resulting mean velocity and flow area. The proposed method was examined in a steep gravel‐bed reach of the Cho‐Shui River in central Taiwan. The estimated stream discharge during three flood events were compared to the prediction by using the stage–discharge relation and the index‐velocity method. The proposed method of this study is capable of computing reasonable values of discharge for an entire flood hydrograph, whereas the other two methods tend to produce large extrapolation errors. Moreover, when the computed discharge is used in 2D flood flow simulation, the proposed method demonstrates better performance than the commonly used stage–discharge and index‐velocity methods.     

Preparation and properties of (BATB–ODPA) polyimide–clay nanocomposite materials

A series of polymer–clay nanocomposite (PCN) materials consisting of 1,4‐bis(4‐aminophenoxy)‐2‐tert‐butylbenzene–4,4′‐oxydiphthalic anhydride (BATB–ODPA) polyimide (PI) and layered montmorillonite (MMT) clay were successfully prepared by an in situ polymerization reaction through thermal imidization up to 300°C. The synthesized PCN materials were subsequently characterized by Fourier‐Transform infrared (FTIR) spectroscopy, wide‐angle powder X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The effects of material composition on thermal stability, mechanical strength, molecular permeability and optical clarity of bulk PI and PCN materials in the form of membranes were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), molecular permeability analysis (GPA) and ultraviolet‐visible (UV/VIS) transmission spectra, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1072–1079, 2004     

Preparation and application of fluorocarbon polymer/SiO2 hybrid materials,part 1: Preparation and properties of hybrid materials

For this study, we first prepared a fluorocarbon polymer and its hybrid materials. We found that fluorocarbon copolymers can produce hydrogen bonds with SiO₂ to form hybrid materials. We also used thermogravimetric analyzer and tested the thermostabilities of the four products, which were ranked as follows: fluorocarbon copolymer/SiO₂ hybrid material > fluorocarbon polymer/SiO₂ hybrid material > fluorocarbon copolymer > fluorocarbon polymer. In addition, we found that, due to the inorganic SiO₂ used, the number of pores and the specific surface areas of the hybrid materials both increased. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1140–1145, 2007     

Synthesis,characterization, and application of PVP/chitosan blended polymers

The purpose of this study was to research the compatibility and application of polyvinylpyrrolidone (PVP)/chitosan blended polymers. The polymers were synthesized at different weight ratios and tested using techniques such as Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis to evaluate the compatibility of the blended materials. Incompatibility occurred when the quantity of chitosan exceeded 75%. The addition of PVP was beneficial for the thermal stability of chitosan, but resulted in inferior strength performance. Furthermore, the blended polymers did not show a color‐enhancement effect, but did show elevated water absorption, chlorine resistance, and colorfastness. In addition, the treated fabrics with a higher chitosan ratio in the blended polymer had antimicrobial properties. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 885–891, 2006