Study of Cryogenic Vaporization Source-Term Due to Heat Transfer from the Solid Substrate

U.S. regulation requires LNG facilities to demonstrate a safe exclusion zone for public safety. European safety case also requires that the facility will demonstrate their risk level within a tolerable limit. Thus, cryogenic liquids (i.e., LNG) release scenarios needs to be modeled to determine consequence severity and perceived risk level. The existing models and tools are very sensitive to the inputs, also known as source-terms. Inaccurate inputs might result in an amplified or subdued consequence severity and may change the estimated risk level and/or safety exclusion zone. Accurate prediction of the source-terms is complex due to the presence of boiling regimes and requires validated models of boiling regimes. A CFD-based approach is taken to model film boiling using Rayleigh-Taylor instability and volume of fluid (VOF) methods. Film boiling simulations for LN2, LO2, and LNG are conducted with a various degree of wall superheat. The simulated results were compared with Berenson and Klimenko correlations to demonstrate that CFD model overcomes the limitations of these correlations. To extend the applicability of these simulations, a first principle model is proposed to enable a faster calculation of heat transfer to cryogenic pool boiling. Medium-scale cryogenic spill experiments have been conducted on an instrumented concrete substrate where LN2, LO2, and liquid air are used. The vaporization rate, temperature, and heat flux profiles are recorded during the experiments. It is found that the effect of the mixture on the LN2 vaporization rate is not significant and the heat conduction inside the concrete substrate is unidirectional. The proposed CFD-based film boiling models for LN2 and LO2 are validated using medium-scale experimental data and are in agreement for higher wall superheats but slightly deviates for the lower wall superheats. The deviation in experimental data can be attributed to the surface roughness and change in boiling regime from film to nucleate. The model for LNG is validated against the experimental data reported in the literature. It is found that the model can capture the vaporization rate reported from the Maplin Sands experiments and other laboratory tests on film boiling

Delphi Technique in Poverty Alleviation: A Case Study

This study aims at investigating scholars thinking intended for poverty alleviation. Two-round Delphi techniques were applied to attain experts’ opinion in support of probable resolution of poverty. Government officials, Non-government executives, University academics, and social & political personalities are considered as scholars. The scholars think that limitation of job is the fundamental cause of poverty that is why the poor are bound to live in vulnerable unhygienic places where inadequate services are prevailing. They also argued that by providing home-based work and especial training that will help them to get job for income generation, the poverty problems could be reduced. As well community-based management similar to labor intensive low-cost housing factory and sanitation plant will also been lead to decrease poverty. To avoid hypothetical discover, the study analyzed poverty alleviation activities of UNDP/GOB project. The UNDP/GOB project entitled ‘Local Partnerships for Urban Poverty Alleviation’ is one of the biggest urban poverty alleviating projects in Bangladesh. There are many successful activities of this project such as community-based micro-credit, sanitation as well as drinking water has been highlighted. The study was undertaken by acquiring primary data from the field survey that employed a structure questionnaire and gathered information emphasis on poverty. Heads of poor households or a member behalf of HH, were used as respondents.

Sensor Fusion and Non-linear MPC controller development studies for Intelligent Autonomous vehicular systems

The demand for safety and fuel efficiency on ground vehicles and advancement in embedded systems created the opportunity to develop Autonomous controller. The present thesis work is three fold and it encompasses all elements that are required to prototype the autonomous intelligent system including simulation, state handling and real time implementation. The Autonomous vehicle operation is mainly dependent upon accurate state estimation and thus a major concern of implementing the autonomous navigation is obtaining robust and accurate data from sensors. This is especially true, in case of Inertial Measurement Unit (IMU) sensor data. The IMU consists of a 3-axis gyro, 3-axis accelerometer, and 3-axis magnetometer. The IMU provides vehicle orientation in 3D space in terms of yaw, roll and pitch. Out of which, yaw is a major parameter to control the ground vehicle’s lateral position during navigation. The accelerometer is responsible for attitude (roll-pitch) estimates and magnetometer is responsible for yaw estimates. However, the magnetometer is prone to environmental magnetic disturbances which induce errors in the measurement. The initial work focuses on alleviating magnetic disturbances for ground vehicles by fusing the vehicle kinematics information with IMU senor in an Extended Kalman filter (EKF) with the vehicle orientation represented using Quaternions. The previous studies covers the handling of sensor noise data for vehicle yaw estimations and the same approach can be applied for additional sensors used in the work. However, it is important to develop simulations to analyze the autonomous navigation for various road, obstacles and grade conditions. These simulations serve base platform for real time implementation and provide the opportunity to implement it on real road vehicular application and leads to prototype the controller. Therefore, the next section deals with simulations that focuses on developing Non-linear Model Predictive controller for high speed off-road autonomous vehicle, which avoids undesirable conditions including stationary obstacles, moving obstacles and steep regions while maintaining the vehicle safety from rollover. The NMPC controller is developed using CasADi tools in MATLAB environment. As mentioned, the above two sections provide base platform for real time implementation and the final section uses these techniques for developing intelligent autonomous vehicular system that would track the given path and avoid static obstacles by rejecting the considerable environmental disturbance in the given path. The Linear Quadratic Gaussian (LQG) is developed for the present application, The model developed in the LQG controller is a kinematic bicycle model, that mimics 1/5th scale truck and cubic spline has been used to connect and generate the continuous target path

WA Agricultural Growth and the State Economy Research Report Volume 1

The impact of state and national policies on the Western Australian (WA) agriculture can not be assessed realistically unless the distinctive characteristics of WA agriculture are taken into account. The objective of this paper is to develop and document an economic information base for WA agriculture by identifying and exploring the main characteristics of its production systems. The study reveals that agriculture plays a more important role in WA than in the rest of Australia (ROA). The share of WA in the national gross value of agricultural production and exports is much higher than her share in the national gross domestic product. The structure of agriculture in terms of product mix is different for WA than for other states in Australia. The farm structure and the overall farming practices in WA are also different from the ROA. The production concentration and product-mix of WA agriculture seem to be very much influenced by the rainfall patterns and topographic conditions

The acquisition and use of information to make investment decisions: a study of financial analysts in China

This study draws upon semi-structured interviews with 23 Chinese financial analysts (Beijing, Shanghai) to examine how they improve their information comprehension through private information search and use such information to evaluate company value. Despite working in state-owned institutions, Chinese financial analysts claim that their analytical framework is similar to their counterparty in the Western setting. However, our results indicate that Chinese analyst's analytical practice is considerably influenced by the specific characteristics of the Chinese listed company both in information acquisition and usage. Private meetings are regarded as a 'value added' information source providing price-sensitive information including product cost structure and possible assets injection from the listed company principle shareholders

Antecedents and consequences of online customer satisfaction: A holistic process perspective

This paper examines the determinants and consequences of online customer satisfaction by considering the entire online shopping experience, based on data collected from our survey of UK consumers in 2016. We found evidence that post online purchase experiences including experiences with order fulfilment, ease of return and responsiveness of customer service are the most significant contributors to online customer satisfaction. Security assurance, customisation, ease of use, product information and ease of check-out, all have significant impact but at much lower levels. The effect of website appearance on customer satisfaction is not significant. Our findings show that online customer satisfaction leads to repurchase intention, and a likelihood of making positive recommendations to others, but not willingness to pay more. We also found the effects of product information, customisation, order fulfilment and responsiveness of customer service on customer satisfaction are stronger for experience products than search products, while there is no significant difference in the effects of other determinants for search products and experience products. Several theoretical and managerial implications are provided, based on our findings