Hydraulic characteristics and startup of anaerobic rotating biological contactors

Abstract

In this study the hydraulic characteristics and the start‐up of anaerobic rotating biological contactor (AnRBC) were investigated experimentally and theoretically. Results of tracer study showed that the AnRBC reactor is a well‐mixed reactor in the first and second stages. Start‐up of the AnRBC reactor was successfully carried out using high strength synthetic wastewaters at hydraulic retention time of 21.6 hours, organic surface loading of 111.4 g‐COD/m²?d, organic volumetric loading of 13.33 Kg‐COD/m³?d, disk rotational speed of 12 rpm and 100% disk submergence. In the steady‐state operating condition, the removal efficiencies of soluble COD and BOD could be up to 71% and 76% for the inlet COD and BOD concentrations of 12,000 and 7,267 mgL^‐1, respectively. The microscopic observations after start‐up of the AnRBC reactor showed that the acetogenic bacteria are significant in the first two stages while the methanogenic bacteria predominate in the last two stages.     

A study on the formation of a measurement scale for the environmental quality of Taiwan’s long-term care institutions by the Delphi method

This study used a two-round modified Delphi technique with a questionnaire survey in order to reach a consensus for the questionnaire; the survey was conducted from September to December 2009. The six indicators for the environmental quality of long-term care institutions in Taiwan are (1) indoor environmental quality, (2) safety equipment for the prevention and management of disasters occurring in residents?? daily lives, (3) provision for assistive devices for residents?? daily use, (4) provision for privacy and individualized space, (5) provision for comfortable and decorated indoor environments, and (6) provision for social interaction space. The scale included 34 items with an acceptable number of panel members and acceptable construct validity. Panel members all highly approved of Indicators 1, 2, and 6. Although they approved of Indicator 3, they suggested that caregivers at institutions should replace the functions of living assistive devices. They approved of Indicator 5; however, they questioned the method for providing comfortable and decorated environments. They approved of Indicator 4; however, they suggested that private space need not be provided in the living room of the institution. In terms of long-term care institution environments in Taiwan, Indicators 1, 2, and 6 were important for protecting residents?? physical and psychological well-being and improving their social interactions. Indicator 3, although important, could be directly replaced by caregivers. Indicator 5 required more implementation methods, while Indicator 4, the living room of the institution, was considered unnecessary.     

Spall-Fracture Physics and Spallation-Resistance-Based Material Selection

Spallation is a fracture mode commonly observed in ballistically/blast-wave-loaded structures. The interaction between decompression waves generated within the target structure produces tensile stresses which, if of a sufficient magnitude, may cause material damage and ultimate fracture (spallation). In this study, the phenomenon of spall-fracture is analyzed within a one-dimensional Lagrangian framework. Two distinct analyses are carried out. Within the first analysis, decompression waves are treated as decompression shocks, which simplified the analysis and enabled the formation of spallation-strength-based material index. In the second analysis, decompression waves are treated as smooth (centered simple) waves. This increased the fidelity of the computational analysis, but the material-selection procedure could be done only numerically and an explicit formulation of the spallation-strength-based material-selection index could not be carried out. Overall, the two analyses yielded similar results for the spallation-strength-based material-selection criterion suggesting that the simpler (decompression shock based) one is still adequate for use in the material-selection process.     

Seqential approach in job shop scheduling

Abstract

This study investigats a new approach‐the sequential approach‐ in job shop scheduling. The objective is to minimize the total of lateness cost and set‐up cost in job shops. Whenever a scheduling decision has to be made as to which job should receive the next processing, this approach considers each cost sequentially. One of the two costs is considered first, and every time all waiting jobs must be examined in terms of this cost, and only those jobs qualified would the second cost apply to and from which a job would be selected for processing. This investigation was carried out by using GASP IV simulation under a variety of job shop situations. The effectiveness of this approach and job selection mechanism constitute the main theme of this study.     

An intelligent skin‐color capture method based on fuzzy C‐means with applications

Consumer behavior is complicated. In the cosmetic market, personal intuition and fashion trends for color selection are guidelines for consumers. A systematic method for female facial skin‐color classification and an application in the makeup market are proposed in this study. In this article, face recognition with a large number of images is first discussed. Then, an innovative method to capture color at selected points is presented and complexion‐aggregated analysis is performed. This innovative method is an extension of face‐recognition theory. Images in RGB format are converted to CIELAB format during data collection and then Fuzzy C‐means theory is used to cluster and group the data. The results are classified and grouped in Lab value and RGB index. Two programs are created. The first program, “FaceRGB,” captures color automatically from images. The second program, “ColorFCM,” clusters and groups the skin‐color information. The results can be used to assist an expert system in the selection of customized colors during makeup and new‐product development.     

Buoyancy effects on the laminar boundary layer heat transfer along vertically moving cylinders

Abstract

The effects of buoyancy forces on the laminar boundary layer flow and heat transfer along vertically moving cylinders are analyzed for the cases of prescribed surface temperature and prescribed wall heat flux in power of streamwise distance. Local similarity solutions are obtained to show the effects of buoyancy parameters and the transverse curvature of the cylinder on the surface friction and heat transfer rate.     

Factors influencing the continuance intention to the usage of Web 2.0: An empirical study

New business models and applications have been continuously developed and popularized on the Internet. In recent years, a number of applications including blogs, Facebook, iGoogle, Plurk, Twitter, and YouTube known as Web 2.0 have become very popular. These aforementioned applications all have a strong social flavor. However, what social factors exert an influence onto their use is still unclear and remains as a research issue to be further investigated. This research studies four social factors and they are subjective norm, image, critical mass, and electronic word-of-mouth. A causal model of the satisfaction and continuance intention of Web 2.0 users as a function of these four social factors is proposed. Results indicate that user satisfaction with Web 2.0 applications significantly affects electronic word-of-mouth, which in turn significantly influences their continuance intention. In addition, subjective norm, image and critical mass all have a significant impact onto satisfaction, which in turn has an indirect significant influence on electronic word-of-mouth. Finally, all social factors have a significant direct impact on continuance intention. Finally, implications for service providers and researchers are discussed.     

Evaluating the criteria for human resource for science and technology (HRST) based on an integrated fuzzy AHP and fuzzy DEMATEL approach

This study intends to use a combination of fuzzy Analytic Hierarchy Process (AHP) and fuzzy Decision-making Trial and Evaluation Laboratory (DEMATEL) method in human resource for science and technology (HRST). Specifically, this study first uses AHP to evaluate the weighting for each criterion and then use DEMATEL method to establish contextual relationships among those criteria. We find out Infrastructure might be more critical since it is a cause and will directly influence human resource for science and technology performance. For human resource for science and technology (HRST), improving Infrastructure might be a better choice for the long period of time. Moreover, Education, R&D Expenses and Immediate output are more important second-tier criteria than Value, Cooperation, Labor Market, Human Capital and Intermediate output. Therefore, the improvement should be started with Infrastructure, particularly on identification of the Education, R&D Expenses and Immediate output.     

Catalyst‐Free GaN Nanorods Synthesized by Selective Area Growth

GaN nanorod formation on Ga‐polar GaN by continuous mode metalorganic chemical vapor deposition selective area growth (MOCVD SAG) is achieved under a relatively Ga‐rich condition. The Ga‐rich condition, provided by applying a very low V/III ratio, alters the growth rates of various planes of the defined nanostructure by increasing relative growth rate of the semi‐polar tilted m‐plane {1–101} that usually is the slowest growing plane under continuous growth conditions. This increased growth rate relative to the non‐polar m‐plane {1–100} and even the c‐plane (0001), permits the formation of GaN nanorods with nonpolar sidewalls. In addition, a new growth mode, called the NH₃‐pulsed mode, is introduced, utilizing the advantages of both the continuous mode and the lower growth rate pulsed mode to form nanorods. Finally, nanorods grown under the different growth modes are compared and discussed.