Comparative study on performance of different twisted tape inserts in the absorber tube of parabolic trough collector (PTC) are presented in this paper. The heat transfer equations for fully developed flow under quasi-steady state conditions have been developed in order to analyze the thermal characteristics and effect of operating parameters on system performance. The numerical simulations have been employed for five different twisted tape inserts with mass flow rate ranging from 0.06 kg/s to 0.16 kg/s. This study reveals, using of twisted tape insert has great promise for enhancing the performance of PTC. Results show that serrated twisted tape inserts with x= 2 yields the best performance among all inserts. The Nusselt number with serrated twisted tape insert (x=2) is found to be 3.56 and 3.19 times over plain absorber of PTC with mass flow rate of 0.06 kg/s and 0.16 kg/s respectively and the corresponding enhancement in thermal efficiency is 13.63 % and 5.41 % respectively. Also the exergy efficiency has been found to be 15.40 % and 16.46% and the corresponding enhancement factor is 1.12 and 1.05 respectively under conditions.

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Purpose In the past decade, much has been written about knowledge management (KM) in the manufacturing; however, less attention has been paid to the Indian automobile ancillary industries located in Chinchwad, Pune. It is suitable to find out the relationship of the factors of the study. It helps in identifying the hierarchy of factors to be taken, and interlinking of production department with KM improves the productivity of the industries. Categorization of these principles based on their driving power (principles which hold other principles) and dependence (principles which are dependent on other principles) has also been examined for KM implementation to study the driving power and dependence power of these principles. This paper aims to determine the roadmap of KM implementation and categorize KM principles based on their driving power for manufacturing industries with the use of the interpretive structural modeling (ISM)-based model. The results indicate that the principles possessing higher driving power, such as KM, inventory control, quality control, productivity and scheduling and their interlinking. The major contribution of this research lies in the development of contextual relationship among various identified factors of KM and determination of their driving and dependence power through a single systemic framework. Design/methodology/approach In this paper, author find out the suitability ISM for Indian Automobile industries to find the relation among the variables. Findings ISM model has been developed for the hierarchy of the identified KM. As ISM model results a hypothetical hierarchy which needs a proper quantitative analysis to evaluate their percentage effectiveness in the hierarchy. Research limitations/implications It is applied to automobile industries with limited number of variables that will show the dependence variable and driving variables and their interrelations. It can be applied other fields to fine the relationship of variables. Practical implications The ISM may be used in supply chain management and total quality management to find interlinking between the variables. Originality/value The limited data collected from Pimpri Chinchwad industrial area of Pune from Maharashtra state (India).

Human body is a natural heterogeneous object optimized in its structure and composition by natural processes over the years of evolution. In this paper, B-spline surface representation method is extended to represent material composition for the development of heterogeneous human body model. Two different approaches namely surface fairing and surface fit are used to create slice by slice model from CT scan data. Both the approaches are compared for different regression parameters. This methodology has potential to represent body internal details accurately with fewer digital input data and is extendable to 3-D solid modeling of human body with applications in FEM analysis, freeform-fabrication and tissue engineering.

The aim of the current study was to extend this line of research and to determine how well bone stiffness predicts yield strength, yield strain, ultimate stress, and ultimate strain for both cortical and cancellous tissue. As will be demonstrated, the mechanical properties of human vertebral cancellous bone in compression and cortical bone in tension are related in similar ways; yield strength and ultimate strength are highly correlated to bone stiffness by a relationship that is the same for both vertebral cancellous and habitually loaded cortical bone.Bone density is defined as means value expressed in Hounsfield units in each pixel. Bone material presents a complex behavior involving heterogeneous and anisotropic Mechanical properties. Moreover, one it is a living issue, therefore its microstructure and mechanical properties evolve with time, in a process called remodeling. This phenomenon has been studied from a long time, and there are many numerical models that have been formulated in the sense to predict the density distribution in various bones, mainly in the femur. A femur, tibia and mandible (all human) were scanned and the image stored in a Dicoma format. Mimics (Materialize, Leuven, Belgium) were used to read and then they were imported in Mimics again, and different material properties were assigned relating the bone mineral density with the Hounsfield Units (HU). There are different relationships between the bone.Then they were imported in MIMICS again, and different material properties were assigned relating the bone mineral density with the Hounsfield Units (HU) (50 materials were considered). In the literature different relationships between the bone apparent density and the HU can be found for the different bone types. In the present study we have used the one of Pang that was a relationship computed for the femur.