Assessment of Heat Transfer Effectiveness: Application to Shell Bitumen Plant, Takoradi, Ghana

Author(s):  
Anthony Simons ◽  
Solomon Nunoo

At Shell Bitumen Plant, Takoradi, Beverley Thermal Fluid Heater (BTFH) generates heat energy to heat thermal fluid (Thermia B) which flows through heat exchanger and then heats bitumen which is to be maintained at temperature range of 140 °C to 160 °C before it is discharged. High rate of heat losses have been observed and in order to maintain the temperature range of bitumen at (140 °C to 160 °C), a lot of heat energy is needed to be generated which means higher fuel consumption for BTFH. Industrial fuel oil is used to fuel the BTFH. This paper assesses the existing insulation system on the plant and seeks to improve on it so as to cut down heat losses. Consequently, the work looked at the estimation of heat losses, selection of materials for heat transfer and lagging purposes. In this wise, the existing laggings were modified by introducing fibreglass between the asbestos and masonry and thus reducing the current heat lost by 78%. Heat from the exhaust gas which would have otherwise, gone wasted, was utilised by redesigning the chimney and this yielded 0.868 kW of heat energy to aid the heating of the bitumen. In the face of rising cost of fuel and taking cognizance of the fact that cheaper natural gas and liquefied petroleum gas could be produced in Ghana, it is recommended that the heater should be fueled by either of these gases.

2020 ◽  
Vol 2020 (4) ◽  
pp. 60-67
Author(s):  
Boris Pruss ◽  
Viktor Romanov ◽  
Yaroslav Prozorov ◽  
Olga Pleskacheva

The paper presents the theory of calculating heat loss through the fences of timber drying chambers. The software for computer modeling of the process of transferring heat energy through the fences of the drying chamber, consisting of various heat-insulating materials, for calculating heat losses during drying of sawn timber is described. The efficiency of the use of modern heat-insulating materials to reduce heat losses during drying of sawn timber has been experimentally confirmed.


Homeopathy ◽  
2020 ◽  
Vol 109 (04) ◽  
pp. 191-197
Author(s):  
Chetna Deep Lamba ◽  
Vishwa Kumar Gupta ◽  
Robbert van Haselen ◽  
Lex Rutten ◽  
Nidhi Mahajan ◽  
...  

Abstract Objectives The objective of this study was to establish the reliability and content validity of the “Modified Naranjo Criteria for Homeopathy—Causal Attribution Inventory” as a tool for attributing a causal relationship between the homeopathic intervention and outcome in clinical case reports. Methods Purposive sampling was adopted for the selection of information-rich case reports using pre-defined criteria. Eligible case reports had to fulfil a minimum of nine items of the CARE Clinical Case Reporting Guideline checklist and a minimum of three of the homeopathic HOM-CASE CARE extension items. The Modified Naranjo Criteria for Homeopathy Inventory consists of 10 domains. Inter-rater agreement in the scoring of these domains was determined by calculating the percentage agreement and kappa (κ) values. A κ greater than 0.4, indicating fair agreement between raters, in conjunction with the absence of concerns regarding the face validity, was taken to indicate the validity of a given domain. Each domain was assessed by four raters for the selected case reports. Results Sixty case reports met the inclusion criteria. Inter-rater agreement/concordance per domain was “perfect” for domains 1 (100%, κ = 1.00) and 2 (100%, κ = 1.00); “almost perfect” for domain 8 (97.5%, κ = 0.86); “substantial” for domains 3 (96.7%, κ = 0.80) and 5 (91.1%, κ = 0.70); “moderate” for domains 4 (83.3%, κ = 0.60), 7 (67.8%, κ = 0.46) and 9 (99.2%, κ = 0.50); and “fair” for domain 10 (56.1%, κ = 0.38). For domains 6A (46.7%, κ = 0.03) and 6B (50.3%, κ = 0.18), there was “slight agreement” only. Thus, the validity of the Modified Naranjo Criteria for Homeopathy tool was established for each of its domains, except for the two that pertain to direction of cure (domains 6A and 6B). Conclusion The Modified Naranjo Criteria for Homeopathy—Causal Attribution Inventory was identified as a valid tool for assessing the likelihood of a causal relationship between a homeopathic intervention and clinical outcome. Improved wordings for several criteria have been proposed for the assessment tool, under the new acronym “MONARCH”. Further assessment of two MONARCH domains is required.


Leadership ◽  
2021 ◽  
pp. 174271502199649
Author(s):  
Dag Jansson ◽  
Erik Døving ◽  
Beate Elstad

The notion of leadership competencies is a much-debated issue. In this article, we propose that how the leader makes sense of his or her competencies is key to leadership practice. Specifically, we look at how leaders reconcile discrepancies between the self-perceived proficiency of various competencies and their corresponding importance. Empirically, we study leaders within the music domain – how choral conductors make sense of their competencies in the shaping of their professional practice. We investigated how choral leaders in Scandinavia ( N = 638) made sense of their competencies in the face of demands in their working situations. A mixed methodology was used, comprising a quantitative survey with qualitative comments and in-depth interviews with a selection of the respondents. The results show that when choral leaders shape their practice, they frequently face competency gaps that compel them to act or adjust their identity. The key to this sensemaking process is how they move competency elements they master to the foreground and wanting elements to the background. The concept of ‘sensemaking affordance’ is introduced to account for how various leader competency categories are negotiated to safeguard overall efficacy.


2021 ◽  
Vol 502 (2) ◽  
pp. 2513-2517
Author(s):  
Stavros Akras ◽  
Denise R Gonçalves ◽  
Alvaro Alvarez-Candal ◽  
Claudio B Pereira

ABSTRACT We report the validation of a recently proposed infrared (IR) selection criterion for symbiotic stars (SySts). Spectroscopic data were obtained for seven candidates, selected from the SySt candidates of Akras et al. by employing the new supplementary IR selection criterion for SySts in the VST/OmegaCAM Photometric H-Alpha Survey. Five of them turned out to be genuine SySts after the detection of H α, He ii, and [O iii] emission lines as well as TiO molecular bands. The characteristic O vi Raman-scattered line is also detected in one of these SySts. According to their IR colours and optical spectra, all five newly discovered SySts are classified as S-type. The high rate of true SySts detections of this work demonstrates that the combination of the H α emission and the new IR criterion improves the selection of target lists for follow-up observations by minimizing the number of contaminants and optimizing the observing time.


2021 ◽  
Vol 11 (4) ◽  
pp. 1428
Author(s):  
Haopeng Wu ◽  
Zhiying Lu ◽  
Jianfeng Zhang ◽  
Xin Li ◽  
Mingyue Zhao ◽  
...  

This paper addresses the problem of Facial Expression Recognition (FER), focusing on unobvious facial movements. Traditional methods often cause overfitting problems or incomplete information due to insufficient data and manual selection of features. Instead, our proposed network, which is called the Multi-features Cooperative Deep Convolutional Network (MC-DCN), maintains focus on the overall feature of the face and the trend of key parts. The processing of video data is the first stage. The method of ensemble of regression trees (ERT) is used to obtain the overall contour of the face. Then, the attention model is used to pick up the parts of face that are more susceptible to expressions. Under the combined effect of these two methods, the image which can be called a local feature map is obtained. After that, the video data are sent to MC-DCN, containing parallel sub-networks. While the overall spatiotemporal characteristics of facial expressions are obtained through the sequence of images, the selection of keys parts can better learn the changes in facial expressions brought about by subtle facial movements. By combining local features and global features, the proposed method can acquire more information, leading to better performance. The experimental results show that MC-DCN can achieve recognition rates of 95%, 78.6% and 78.3% on the three datasets SAVEE, MMI, and edited GEMEP, respectively.


2016 ◽  
Vol 04 (03) ◽  
pp. 156-164
Author(s):  
Deepak Bansal ◽  
Shruti Sharma ◽  
Manjit Kumar ◽  
Amrit Khosla

AbstractAn altered facial appearance is more difficult to face, than problems related to ill-fitting denture or eating. The selection of maxillary anterior teeth for complete denture has long posed problem in clinical practice and a controversy about the best method to employ still exists. An attempt is made in the present study to clinically correlate the face form with maxillary central incisor tooth form in males and females of Davangere population. In 1914, Leon William's projected the “the form method” where he classified facial forms as square, tapering, and ovoid. Maxillary central incisors were selected according to the facial forms.Of total 100 subjects four different tooth forms and face forms were evaluated. They are: square, ovoid, square-tapered, tapered. No significant correlation existed between face form in male and females. Females exhibited greater correlation between face forms and inverted tooth form but that correlation is not sufficient to serve as a guide for selection of anterior teeth.


2012 ◽  
Vol 532-533 ◽  
pp. 417-421
Author(s):  
Chang Li Song ◽  
Jing Ji

In order to improve the pipe dissipating area, a kind of new pipe with grid plate is proposed in this paper. Based on the basic principle of heat transfer and energy conservation law, by finite element software ANSYS the simulation analysis of the steady-state heat transfer of the new pipeline is carried out, process of ANSYS modeling, loading and solving is introduced in detail, the distribution of temperature and stress for pipe with a grid plate is given, these can provide the foundation for the selection of the optimal diameter of the grid plate and transient heat transfer analysis of pipe.


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