43 research outputs found
Wormhole in gravity
In this paper, exact asymptotically flat wormhole solutions in the context of
symmetric teleparallel gravity, i.e., theory of gravity, are
investigated. Since modified theories of gravity provide new field equations,
we have analyzed some possible wormhole solutions by using modified field
equations. Four different forms of the function are considered then the
shape function is calculated with some different equations of state. Also we
have used a power-law shape function with these models, which lead to an
asymptotically barotropic equation of state. Some physical and mathematical
properties of the solutions, like energy conditions and boundary conditions,
are addressed .Comment: 12 pages, 16 figure
Traditional uses of medicinal plants to prevent and treat diabetes; an updated review of ethnobotanical studies in Iran
A COMPARISON BETWEEN THE PERTURBED-CHAIN STATISTICAL ASSOCIATING FLUID THEORY EQUATION OF STATE AND MACHINE LEARNING MODELING APPROACHES IN ASPHALTENE ONSET PRESSURE AND BUBBLE POINT PRESSURE PREDICTION DURING GAS INJECTION
Predicting asphaltene onset pressure (AOP) and bubble point pressure (Pb) is essential for optimization of gas
injection for enhanced oil recovery. Pressure-Volume-Temperature or PVT studies along with equations of state (EoSs) are widely
used to predict AOP and Pb. However, PVT experiments are costly and time-consuming. The perturbed-chain statistical associating
fluid theory or PC-SAFT is a sophisticated EoS used for prediction of the AOP and Pb. However, this method is computationally
complex and has high data requirements. Hence, developing precise and reliable smart models for prediction of the AOP and Pb is
inevitable. In this paper, we used machine learning (ML) methods to develop predictive tools for the estimation of the AOP and Pb
using experimental data (AOP data set: 170 samples; Pb data set: 146 samples). Extra trees (ET), support vector machine (SVM),
decision tree, and k-nearest neighbors ML methods were used. Reservoir temperature, reservoir pressure, SARA fraction, API gravity,
gas−oil ratio, fluid molecular weight, monophasic composition, and composition of gas injection are considered as input data. The
ET (R2: 0.793, RMSE: 7.5) and the SVM models (R2: 0.988, RMSE: 0.76) attained more reliable results for estimation of the AOP
and Pb, respectively. Generally, the accuracy of the PC-SAFT model is higher than that of the AI/ML models. However, our results
confirm that the AI/ML approach is an acceptable alternative for the PC-SAFT model when we face lack of data and/or complex
mathematical equations. The developed smart models are accurate and fast and produce reliable results with lower data
requirements
Innovation and HRM : absences and politics
This article analyses the role of HRM practices in the implementation of an innovative cross-functional approach to new product development (concurrent engineering, CE) in Eurotech Industries. Contrary to CE methodology stipulations, and despite supportive conditions, HRM received scant attention in the implementation process. Organizational power and politics were clearly involved in this situation, and this article explores how their play created such HRM ‘absences’. The article builds on a four-dimensional view of power in order to provide a deeper understanding of the embedded, interdependent and political nature of HRM practice and innovation.<br /
An automated coding and classification system with supporting database for effective design of manufacturing systems
The philosophy of group technology (GT) is an important concept in the design of flexible manufacturing systems and manufacturing cells. Group technology is a manufacturing philosophy that identifies similar parts and groups them into families. Beside assigning unique codes to these parts, group technology developers intend to take advantage of part similarities during design and manufacturing processes. GT is not the answer to all manufacturing problems, but it is a good management technique with which to standardize efforts and eliminate duplication. Group technology classifies parts by assigning them to different families based on their similarities in: (1) design attributes (physical shape and size), and/or (2) manufacturing attributes (processing sequence). The manufacturing industry today is process focused; departments and sub units are no longer independent but are interdependent. If the product development process is to be optimized, engineering and manufacturing cannot remain independent any more: they must be coordinated. Each sub-system is a critical component within an integrated manufacturing framework. The coding and classification system is the basis of CAPP and the functioning and reliability of CAPP depends on the robustness of the coding system. The proposed coding system is considered superior to the previously proposed coding systems, in that it has the capability to migrate into multiple manufacturing environments. This article presents the design of a coding and classification system and the supporting database for manufacturing processes based on both design and manufacturing attributes of parts. An interface with the spreadsheet will calculate the machine operation costs for various processes. This menu-driven interactive package is implemented using dBASE-IV. Part Family formation is achieved using a KAMCELL package developed in TURBO Pascal.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46606/1/10845_2004_Article_BF00123696.pd
The effectiveness of heparin, platelet-rich plasma (PRP), and silver nanoparticles on prevention of postoperative peritoneal adhesion formation in rats
Genomic and Expression Analyses Define MUC17 and PCNX1 as Predictors of Chemotherapy Response in Breast Cancer
A review of therapeutic and pharmacological effects of thymol
Thymol (C10H14O) is a monoterpene which is considered a phenolic component and is present in many vegetable oils. Thymol is an aromatic essence which is known as disinfectant in traditional medicine. Thymol is found in plants and has properties such as antibacterial, antipyretic, antispasmodic, antifungal, antioxidant, and hepatorotective, anti worm, antispasmodic for rats tracheal smooth muscles, gastroprotective, antihyperglycemic, antihyperlipidemic, analgesic, acaricide, and antiepileptic. Thymol is a medicinal, plant-based component with pleasant taste and smell and is found in many medicinal plants including Thymus vulgaris, and Carum copticum. Because it is inexpensive and exerts pharmaceutically peerless effects, it could be used to heal many of the diseases and may be commercially available in different countries in the future