1,579 research outputs found

    FMEA of gasketed and non-gasketed bolted flanged pipe joints

    Get PDF
    Limited work is available in the literature on the Failure Mode and Effects Analysis of bolted flanged pipe joints. From previous comparative reliability studies of both gasketed and non-gasketed bolted flanged pipe joints, generally it is found that both the joints types are of high integrity and perform well in excellent service under appropriate installation and maintenance conditions. However, based on certain factors better functional safety for non-gasketed joints can be achieved. All studies have been performed based on operational information and reported observations. This study reported herein presents a detailed failure mode and effects analysis (FMEA) in the light of industrial surveys, analysis, experimental work and subsequent observations in addition to previous studies. The aim of the study is to increase the reliability knowledge of the gasketed and non-gasketed flanged pipe joints and thereby to increase the basis for finding the optimal pipe connection based on surveys, observation and experimental studies performed

    Stamina of a non-gasketed flange joint under combined internal pressure, axial and bending loading : an experimental study

    Get PDF
    The performance of a bolted flange joint is characterized mainly by its 'strength' and 'sealing capability'. A number of numerical and experimental studies have been conducted to study these characteristics under internal pressure loading conditions alone. However, limited work is found in the literature under conditions of combined internal pressure and axial loading. The effect of external, axial loading pressure being unknown, the optimal performance of the bolted flange joint cannot be achieved. Current design codes do not address the effects of axial loading on structural integrity and sealing ability. To study joint strength and sealing capability under combined loading conditions, an extensive experimental and numerical study of a non¬gasketed flange joint was carried out. Actual joint load capacity was determined at both design and test stages with the maximum external axial loading that can be applied for safe joint performance. Experimental and numerical results have been compared and overall joint performance and behaviour is discussed in detail

    Determinants of Food Acceptance and Micro-Nutrient Deficiency in Preschoolers: A Case Study of Households from Karachi, Pakistan

    Get PDF
    This study attempts to find out the determinants of food acceptance and micro-nutrient deficiency in preschool children from Karachi, Pakistan. Primary data was collected through survey from 400 households by interviewing and filling up the questionnaire. Index for food acceptance and micro-nutrient deficiency were constructed with the help of related questions from the questionnaire. Econometric models were developed and Logit techniques was employed to estimate probability of end indicator. Our results show that increase Micro-Nutrient Deficiency (MND) may cause lower level of Food Acceptance and vice versa. On the other hand, modeling food acceptance may indicate higher level of MND among preschoolers reduce the acceptance level of appropriate food. Other important variables like Household Income, Mother’s Literacy and Mother’s Maternal Knowledge showed significant effects and appropriate signs of coefficients as per expectations. On the basis of these findings, if government targets the core independent variables that are identified in the analysis, Food Acceptance level can be increased amongst the children and Micro- Nutrient Deficiency could then be reduced. Consequently government intervention, both long term and short term are needed to provide and regulate the food acceptance behavior either at household level or at other form so that our generation could be healthier and more productive which would lead the economic growth of a country which is abundant in labor.Food acceptance, preschoolers, nutritional status, micronutrient deficiency

    al-Misbāh fī al-Nahw By Nāsir al-Dīn al-Mutarrizī al-Nahwī (d. 610/1213) A Critical Edition of the Text with the Life History of the Author

    Get PDF
    Nāsir al-Dīn al-Mutarrizī al-Nahwī (d.610/1213) was one of the most renowned figures in the field of Arabic Grammar. He has left an indelible mark on the world of Arabic language and literature. He is also known as the successor of al-Zamakhsharī. He wrote a number of books but his al-Misbāh fī al-Nahw gained prominence at a level that no other book in this field could claim to achieve. For this reason, a great number of commentaries have been written in every age, of which the most famous are al-Daw and Khulāsat al-I‘rāb written by Tāj al-Dīn al-Isfrā’īnī and ‘Abd al- Karīm al-Tūsī (better known as Hājjī Bābā) respectively. Moreover, its translation into other languages also demonstrates its value as a useful book. Although al-Misbāh has been edited on more than one occasion, the published editions do not fulfil the needs and requirements of modern academic research criteria. The basic aim of this thesis is to present this book with a current modern research style so that the students, teachers and ordinary readers of Arabic language and literature may benefit from this work. This thesis is divided into two parts. The first part deals with the life history of the author and his other works. A brief note of the environment under which he grew up (generally referred to as the ‘Seljuk’ period) is also included in this part. The second part consists of a text edition that deals with the derivation (Takhrīj) of syntactical issues together with the differing opinions of grammarians on syntactical/grammatical issues. This part also proffers the idiomatic English translation of al-Misbāh

    Model of eco-socially conscious consumer behaviour related to choice and use of personal cars: evidence from an emerging economy

    Get PDF
    This thesis focuses on developing a model of eco-socially conscious consumer behaviour related to choice and use of personal cars. It presents empirical evidence relating to the factors that must be considered when promoting environmentally friendly cars (noted as alternative fuel vehicles (AFVs) throughout the thesis), especially in an emerging economy such as Pakistan. The rationale and motivation behind this project is that there is an increasing rate of environmental problems such as air pollution and CO₂ in emerging economies and relatively lower competence in developing strategies aimed at improving climate change resilience. Together with changing the climate, anti-environmental anthropogenic activities make it more difficult for affected communities to prosper. To curb these environmental problems, studies reported in the academic literature have suggested taking measures to reduce the impact of human activities on the environment and regulating consumption of environmentally harmful products. In response to these emerging demands, marketers have invested heavily, regarding both product development and promotion of pro-environmental behaviours, in various domains of commercial interest. One such area is the use of personal cars, a sector that is proliferating and, given that CO₂ emissions from cars are one of the most significant sources of environmental problems (particularly global warming), there is a need to promote alternative fuel vehicles (AFVs) and eco-social behaviours in the use of personal cars. This thesis reports on two major studies to answer three underlying research questions. The first study focuses on two research questions. The first research question, RQ1, explores how automobile industry consumers (those in the personal cars segment) define eco-socially conscious behaviour (ESCCB) related to the choice and use of personal cars in Pakistan. The second research question, RQ2, attempts to identify the profiles of different customer segments based ESCCB defined in RQ1. The second study is focused on the theoretical explanation of factors that are suggested in the literature to affect ESCCB related to the choice and use of personal cars. The Theory of Planned Behaviour (TPB) and Value-Beliefs-Norms Theory (VBN) have been converged to provide a holistic explanation of ESCCB. Based on scientific methodologies recommended for new scale development, the results reported in this thesis suggest that ESCCB related to choice and use of personal cars is a latent construct manifested in three underlying dimensions: eco-social use, eco-social purchase and eco-social conservation. A market segmentation approach using cluster and discriminant analysis suggests that three consumer segments exist in the Pakistani automobile market based on response towards eco-social behaviour and inclination towards choosing AFVs. The first segment, the conservatives, are not concerned about the environmental issues, prefer conventional cars, and are least sensitive to the eco-social use of personal cars. The second segment, the indifferents, are unsure whether they should buy AFVs and whether this will positively affect the environment. The third segment, and the largest one (51%), the enthusiasts, are highly inclined towards purchasing AFVs and eco-social use of personal cars to reduce the impact of the use of personal cars on the environment. The findings of Study 1 hold significant implications for marketing practitioners and policymakers. Some conceptual and methodological limitations are highlighted. The results of Study 2 suggest that the Theory of Planned Behaviour (TPB), Value- Belief-Norm (VBN) Theory and the integrated model, were all found to be very strong in explaining not only ESCCB intentions but also actual behaviour, related to purchase of environmentally friendly cars and conservation of fuel. Results showed that the integrated model based on TPB and VBN was stronger in predicting ESCCB-conservation (49.7 per cent variance) than TPB (46.7 per cent variance) and VBN (26.7 per cent variance). A similar pattern of results was evident for ESCCB-purchases (integrated model: 14.8 per cent variance, TPB: 12.5 per cent variance, VBN: 10.8 per cent variance). However, the predictive power of the three models for actual eco-socially conscious consumer behaviour (ESCCB) had slightly different results. TPB was found stronger to predict actual ESCCB (33.4 per cent variance), followed by the integrated model based on TPB and VBN (31.9 per cent variance) and VBN (15.7 per cent variance). This study contributes to both theoretical and practical aspects linked with ecosocially conscious consumer behaviour related to choice and use of personal cars. These contributions extend the theoretical literature related to eco-social behaviours and provides policy measures for marketing practitioners and public policy makers. The study findings not only provide guidelines for automobile related behaviours but can also be generalised in other areas

    Cognitive Programs Memory - A Framework for Integrating Executive Control in STAR

    Get PDF
    Cognitive Programs are algorithms which guide the execution of visual tasks in the Selective Tuning (ST) model and its extension Selective Tuning Attentive Reference (STAR). However, no framework exists that allows for their rapid development, parameterization and execution. In this thesis we propose that a basis set of elemental operations called Neural Primitives (NP) in conjunction with other control elements constitute a Cognitive Program. The Neural Primitives are biologically inspired computations that dictate the transformation functions from one representation to another and form the foundation of this thesis. Therefore a key theme here is using low level neural computations, the NPs to perform higher level cognitive functions that are required for task demands. This thesis also introduces a database like structure called the Cognitive Programs Memory (CPM) that holds a set of predefined CPs which are accessible by the visual task executive (vTE) - a component of STAR with a major role of controlling task execution. The CPs have been tested on the execution of three psychophysical experiments demonstrat- ing how a sequence of operations can be used to complete visual tasks. The CPs have also been tested on two experiments demonstrating that the application of the NP operations result in qualitatively similar neural tuning curves to neurophysiological data