Parametric Study of Vertical Ground Loop Heat Exchangers for Ground Source Heat Pump Systems

We report on a numerical study conducted to investigate the effect of various parameters on the heat exchange inside a vertical ground loop heat exchanger (VGLHE) for a ground-source heat pump (GSHP) system. The simulations were conducted for three piping configurations of the ground loop which were U-Tube, Concentric pipes and Spiral. The results show a linear temperature rise along the pipe length for the U-Tube configuration. The Concentric pipes configuration shows two distinct linear trends for the temperature rise; a slow temperature rise during the downward flow through the inner pipe and a higher temperature rise during the upflow through the annulus. The Spiral configuration shows a steeper slope for the temperature rise in the spiral section and almost a flat slope for the temperature rise in the straight vertical section of the pipe. The research also examines a simulation case of integrating a VGLHE inside of a micro-pile foundation system

On Overall Heat Transfer Coefficient in EOR Injection Wellbore

Heat losses in oil wells can be very significant, especially when comes to EOR Steam injection wells. the loss of thermal energy through the well completion is unavoidable, However , the knowledge of the amount of heat loss is important and can only done if the value of overall heat transfer coefficient is known. This study aims to calculate the overall heat transfer coefficient and analyze the effect of changing completion design and other parameters inside the well to study the effect of different completion and surface components on the overall heat transfer coefficien

Energy Transfer and Coherence in Coupled Oscillators with Delayed Coupling: A Classical Picture for Two-Level Systems

The Frimmer-Novotny model to simulate two-level systems by coupled oscillators is extended by incorporating a constant time delay in the coupling. The effects of the introduced delay on system dynamics and two-level modeling are then investigated and found substantial. Mathematically, introducing a delay converts the dynamical system from a finite one into an infinite-dimensional system. The resulted system of delay differential equations is solved using the Krylov method with Chebyshev interpolation and post-processing refinement. The calculations and analyses reveal the critical role that a delay can play. It has oscillatory effects as the main dynamical eigenmodes move around a circle with a radius proportional to the coupling strength and an angle linear with the delay. This alteration governs the energy transfer dynamics and coherence. Accordingly, both, the delay and the coupling strength dictate the stability of the system. The delay is the main related parameter as for certain intervals of it, the system remains stable regardless of the coupling. A significant effect occurs when one of the main modes crosses the imaginary axis, where it becomes pure imaginary and dampingless. Thus, the two states energies can live and be exchanged for an extremely long time. Furthermore, it is found that the delay alters both the splitting and the linewidth in a way further influencing the energy transfer and coherence. It is found also that the delay should not be large to have significant effect. For example, for an optical system with 500 nm wavelength, the critical delay can be in tens of attoseconds

Investigating the impact of food tourism vlogger entrepreneurs' language characteristics on audiences' attitude and behaviours

Purpose Despite entrepreneurial linguistic style gaining increased attention in entrepreneurship studies, the field for digital vlogger entrepreneurs still lacks a comprehensive understanding of how linguistic patterns enhance audiences attitude and behaviour. This study aims to propose a conceptual model of “language-mental imagery-attitude-behaviour model” that leads to the examination of rich sensory language style of food travel vlogger entrepreneurs and its persuasive effect on audiences' attitude and behavioural intention. Design/methodology/approach The present study utilises a stimulus-based survey method that involves a sensory-rich vlog script extracted from a high social media engagement authentic vlog. Data are collected through an online questionnaire distributed to a sample of 355 participants via the Amazon Turk mechanism. The study employs confirmatory factor analysis and structural equation modelling to test the proposed hypotheses, with the aim of contributing to the advancement of theories of embodied cognition in entrepreneurial language by examining the attitudes and behaviours of audiences exposed to sensory-rich language. The findings of this research provide valuable insights into the effects of sensory-rich language on audience responses and can inform future research on the role of embodied cognition in entrepreneurial communication. Findings The findings demonstrate that vlogger entrepreneurial sensory-rich linguistic communication style positively influence audiences' attitude, behavioural involvement with food and intention to taste. Visit intention will be enhanced via the mediating effects of attitude, behavioural involvement with food and intention to taste. Practical implications This research highlights the significance of sensory-rich language for vlogger entrepreneurs in entrepreneurial communication, digital storytelling and for destination marketing enterprises in creating a digital sensory engagement marketing strategy. Originality/value The study contributes to the literature by elucidating the theories of embodied cognition in entrepreneurial communication. By examining the relationships between vlogger communication evoked mental imagery, audiences attitude and behaviours, this study provides novel insights into the effectiveness of sensory-rich language in vlogger entrepreneurial communication and its impact on audience engagement. These findings have important implications for communication scholars and practitioners alike, shedding light on the role of embodied cognition in entrepreneurial language and the potential of sensory-rich language to enhance audience engagement

Observations of indirect exciton trapping in one- and two-dimensional magnetic lattices

A simple method to create and control magnetic potentials onto coupled quantum wells is demonstrated for indirect-exciton magnetic confinement. Localized inhomogeneous magnetic potentials with periodically distributed local minima and maxima, known as magnetic lattices, are projected into the plane of the coupled quantum wells and used for the spatially distributed two-dimensional indirect-exciton trapping, in which case localized indirect-excitons are observed. The indirect-exciton trapping mechanism is examined by controlling external magnetic field bias resulting in a shift of the localized excitonic lattice

A Language and Preprocessor for User-Controlled Generation of Synthetic Programs

We describe Genesis, a language for the generation of synthetic programs. The language allows users to annotate a template program to customize its code using statistical distributions and to generate program instances based on those distributions. This effectively allows users to generate programs whose characteristics vary in a statistically controlled fashion, thus improving upon existing program generators and alleviating the difficulties associated with ad hoc methods of program generation. We describe the language constructs, a prototype preprocessor for the language, and five case studies that show the ability of Genesis to express a range of programs. We evaluate the preprocessor’s performance and the statistical quality of the samples it generates. We thereby show that Genesis is a useful tool that eases the expression and creation of large and diverse program sets

Investigating the Effects of Trees and Butterfly Barriers on the Performance of Optimistic GVT Algorithm

The final publication is available at www.springerlink.comThere is two approaches for handling timing constraints in a heterogeneous network; conservatives and optimistic algorithms. In optimistic algorithms, time constraints are allowed to be violated with the help of a time wrap algorithm. Global Virtue Time (GVT) is a necessary mechanism for implementing time wrap algorithm. Mattern [2] has introduced an algorithm for GVT based computation using a ring structure. which showed high latency. The performance of this optimistic algorithm is optimal since it gives accurate GVT approximation. However, this accurate GVT approximation comes at the expense of high GVT latency. Since this resultant GVT latency is not only high but may vary, the multiple processors involve in communication remain idle during that period of time. Consequently, the overall throughput of a parallel and distributed simulation system degrades significantly In this paper, we discuss the potential use of trees and (or) butterflies structures instead of the ring structure. We present our analysis to show the effect of these new mechanisms on the latency of the system.http://link.springer.com/chapter/10.1007%2F978-90-481-3660-5_7