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Article
Publication date: 8 February 2016

Jingsen Zhang, Jing Zhang and Yanchao Zhai

This paper aims to elucidate the geochemical characteristics of the hydrothermally altered rocks with gold mineralization and the elemental transfers in hydrothermal alteration…

Abstract

Purpose

This paper aims to elucidate the geochemical characteristics of the hydrothermally altered rocks with gold mineralization and the elemental transfers in hydrothermal alteration hosted in alkaline complex in Hongshan area, Taihang Orogen, North China, and preliminarily discuss the relationship between the gold mineralization and the hydrothermal alteration.

Design/methodology/approach

Based on detailed field investigation, sampling and petrographical observation, major oxides and trace elements of nine rock samples are analyzed, and the method of mass balance equation is used in calculation of the elemental transfer.

Findings

Three alteration stages in the Hongshan area are identified, which are the early, main and late alterations. The early one is characteristic of extensive pyritization in the complex, which is related to the mantle-derived magmas and occurs before gold mineralization. The main one is characterized by developing a great deal of altered rock in fracture zones with the gain of many elements and the loss of a few elements. The late one is dominated by limonitization, that is limonite replacing the early pyrite or Fe2O3 replacing FeO in rocks. In the main alteration, the altered rocks obviously gain fluid component (LOI, i.e. loss on ignition) and elements such as V, As, Rb, Au, La, Ce and Nd and total rare earth elements (REEs). Elements such as K, Fe, Cu, Zn, Y, Mo, Sb, W, Re and U are gained in some altered rocks. Na and Sr are lost in all altered rocks, and Th and Bi are lost in some ones in the meantime. The following elements: Si, Mg, Mn, Ca, Li, Sc, Cr, Co, Ni, Zr, Ag, Ba and Hg show either gain or loss in different altered rocks. Au is notably enriched in the hydrothermal alteration. The elemental gain or loss in the altered rocks indicates that the main mineralization develops extensive de-alkalinization, local potassic metasomatism, silicification or desilicification.

Details

World Journal of Engineering, vol. 13 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 March 1989

D.E. Riemer

This paper introduces thermal‐stress analysis methods which follow electrical engineering procedures. The spring constant or c‐value is found to be related to the electrical…

Abstract

This paper introduces thermal‐stress analysis methods which follow electrical engineering procedures. The spring constant or c‐value is found to be related to the electrical impedance, combining dimensions and material characteristics in a performance parameter which simplifies calculations. Voltage is used to represent thermal deformation, and thermal forces are modelled as currents. Relationships equivalent to Ohm's Law are applied to calculate thermal stresses in leads or traces of surface‐mount assemblies. The thermal performance of laminates, e.g., thermal expansion coefficients of interconnect boards with a restraining core, and the thermal stresses in the bonded layers, are derived from the analysis of an electrical network which represents the composite structure. The method provides visual concepts which facilitate a first‐order solution of engineering problems related to thermal stress.

Details

Soldering & Surface Mount Technology, vol. 1 no. 3
Type: Research Article
ISSN: 0954-0911

Article
Publication date: 1 February 1977

A decision to publish what appears to be the manual of instructions used by indexers to Food Science and Technology Abstracts implies that it is a well tried document which works…

Abstract

A decision to publish what appears to be the manual of instructions used by indexers to Food Science and Technology Abstracts implies that it is a well tried document which works in practice. It does not make easy reading, and personal guidance and instruction on its application to a wide range of actual works would be helpful before it could be easily used in practice. Some examples are provided on left hand pages to illustrate the points made on the right, but a wider range, including more of the difficult borderline cases, is required to ensure proficiency in the system. Where no examples are appropriate, the left hand pages are filled by computer graphics which are perhaps the most attractive features of the book and which may in future years find their way into the folders of miscellaneous prints in second hand book shops.

Details

Program, vol. 11 no. 2
Type: Research Article
ISSN: 0033-0337

Book part
Publication date: 12 July 2021

Dhinesh Sugumaran, Kogila Vani Annammala, Abdull Rahim Mohd Yusoff, Zulkifli Yusop, Nur Athirah Mohamad and Anand Nainar

Southeast Asia has been actively undergoing land conversion into agricultural lands over past few decades. This creates the challenges to the nation in dealing with the non-point…

Abstract

Southeast Asia has been actively undergoing land conversion into agricultural lands over past few decades. This creates the challenges to the nation in dealing with the non-point source pollutants in many fluvial systems, thus requiring an effective approach in sediment source apportionment for an appropriate target mitigation procedure. The trace element property from different source points was used for catchment classification of Galas River. Sediment sample collection was carried out at the sources and sink areas of the catchment system. Fine sediment was analysed using X-ray fluorescence to obtain elemental composition followed by the statistical test and numerical model. Out of 83 elements, 12 elements (Mn, Ca, Cr, Ga, Dy Hf, Y, V, Th, Pb, Zn and Sr) have been selected as best tracer signatures. The solver model has indicated Pergau River as the major sediment contributor to this large catchment system. The model output could directly be proportional with the land-use practice, indicating excessive terrestrial alteration has taken place within the sites for agricultural plantation purposes. Thus, this highly recommends for the decision-making use to the targeted areas to overcome the serious sedimentation issues caused by the tillage operation in affected stream points and to improve the watershed quality.

Details

Water Management and Sustainability in Asia
Type: Book
ISBN: 978-1-80071-114-3

Keywords

Article
Publication date: 2 April 2024

Chenyu Zhang, Hongtao Xu and Yaodong Da

Thermal protection of a flange is critical for preventing tower icing and collapse of wind turbines (WTs) in extremely cold weather. This study aims to develop a novel thermal…

22

Abstract

Purpose

Thermal protection of a flange is critical for preventing tower icing and collapse of wind turbines (WTs) in extremely cold weather. This study aims to develop a novel thermal protection system for the WTs flanges using an electrical heat-tracing element.

Design/methodology/approach

A three-dimensional model and the Poly-Hexacore mesh structure are used, and the fluid-solid coupling method was validated and then deployed to analyze the heat transfer and convection process. Intra-volumetric heat sources are applied to represent the heat generated by the heating element, and the dynamic boundary conditions are considered. The steady temperature and temperature uniformity of the flange are the assessment criteria for the thermal protection performance of the heating element.

Findings

Enlarging the heating area and increasing the heating power improved the flange's temperature and temperature uniformity. A heating power of 4.9 kW was suitable for engineering applications with the lowest temperature nonuniformity. Compared with continuous heating, the increased temperature nonuniformity was buffered, and the electrical power consumption was reduced by half using pulse heating. Pulse heating time intervals of 1, 3 and 4 h were determined for the spring, autumn and winter, respectively.

Originality/value

The originality of this study is to propose a novel electrical heat-tracing thermal protection system for the WTs flanges. The effect of different arrangements, heating powers and heating strategies was studied, by which the theoretical basis is provided for a stable and long-term utilization of the WT flange.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 7 June 2011

Melissa Cheung and Jan Hidders

This paper aims to present how iterative round‐trip modelling between two different business process modelling tools can be enabled on a conceptual level. Iterative round‐trip…

1886

Abstract

Purpose

This paper aims to present how iterative round‐trip modelling between two different business process modelling tools can be enabled on a conceptual level. Iterative round‐trip modelling addresses model transformations between high‐level business and executable process models, and how to maintain these transformations in change time. Currently, the development of these process models is supported by different tools. To the authors' best knowledge, no coherent collaborative tool environment exists that supports iterative round‐trip modelling.

Design/methodology/approach

This paper is primarily based on a literature review of state‐of‐the‐art business to IT transformations regarding business process modelling. The architecture of integrated information systems (ARIS) and Cordys tools are used as an example case in this research. ARIS is a business process analysis (BPA) tool suited for analyzing and designing business processes, while the execution and monitoring of these processes is allowed by Cordys, a business process management suite (BPMS). The theory is used for transforming between ARIS event‐driven process chains from the business perspective and business process modelling notation in Cordys from the IT perspective.

Findings

A conceptual framework is proposed to couple a BPA and BPMS tool for round‐trip business process modelling. The framework utilizes concepts from the model‐driven architecture for structurally addressing interoperability and model transformations. Ensuring iterative development with two tools requires traceability of model transformations.

Practical implications

In many organizations, BPA and BPMS tools are used for business process modelling. These are in practice often two different worlds, while they concern around the same business processes. Maintaining multiple versions of the same process models across two tools is a considerable task, as they often are subject to design changes. Interoperability between a BPA and BPMS tool will minimize redundant activities, and reduce business to IT deployment time.

Originality/value

This research provides a theoretical base for coupling a BPA and BPMS tool regarding iterative round‐trip modelling. It provides an overview of the current state‐of‐the‐art literature of business process modelling transformations, and what is necessary for maintaining interoperability between tools. The findings indicate what is expected in tool support for iterative development in business process modelling from analysis and design to execution.

Article
Publication date: 15 May 2017

Matevz Juvancic and Spela Verovsek

Spatial identity is an important constituent of general cultural identity in that it provides its share of continuity, sustainability, character and inertia. The purpose of this…

Abstract

Purpose

Spatial identity is an important constituent of general cultural identity in that it provides its share of continuity, sustainability, character and inertia. The purpose of this paper is to trace spatial identity’s formulation, reflection and perception within the mainstream media. The authors are particularly interested in spatial identity’s general aspect, consisting of architectural and other elements that give spatial character to places, making them both common and recognisable at the same time. The proposed spatial identity presence index is one of the indicators through which stakeholders in cultural heritage management could monitor, and even manage, the public perception of built heritage’s wider context.

Design/methodology/approach

The research seeks wider relevance through the development of new methodology that combines web search services, visual data quantification, and data mining methods, and compares this with expert opinion. The research methodology is showcased and established in terms of the connection between the fundamental work in relation to Slovenian architectural landscapes from the pre-internet era and spatial identity’s web reflection as broadcast and collectively co-shaped by the internet-permeated society more than 20 years after the internet’s inception.

Findings

The findings indicate that results based on expert opinion and results acquired by counting spatial character carrier elements are aligned.

Originality/value

The introduced index of web-sourced spatial identity presence measures web-projected spatial characteristics in selected settlements. It is applicable in similar cases where the existing body of work on local spatial identity allows it, and can be used for comparative purposes. It also has social, economic and political connotations.

Details

Journal of Cultural Heritage Management and Sustainable Development, vol. 7 no. 2
Type: Research Article
ISSN: 2044-1266

Keywords

Article
Publication date: 25 May 2021

Niki Glaveli, Fotios Vouzas and Myrsine Roumeliotou

The current study provides insights on the application of critical soft TQM practices in primary and secondary education and their impact on teachers' job satisfaction (TJS).

Abstract

Purpose

The current study provides insights on the application of critical soft TQM practices in primary and secondary education and their impact on teachers' job satisfaction (TJS).

Design/methodology/approach

Based on a review of the literature related to TQM application in primary and secondary education, six soft TQM elements were traced as critical to the success of TQM implementation in the school environment: participation/involvement in continuous improvement, teamwork, empowerment, appraisal systems/recognition and reward for quality, training and development (T&D) and leadership (vision/commitment to quality culture). Moreover, their relationship to JS was theoretically founded and empirically tested. An online questionnaire was used as the research instrument. The participants were 200 primary and secondary public school teachers working in urban, semi urban and rural regions of Greece. After assessing the validity and reliability of the measurement scales, multiple regression analysis was applied to test the hypothesized relationships.

Findings

The research findings revealed that leadership and empowerment are the most highly implemented TQM practices in primary and secondary education. Moreover, participation/involvement, appraisal systems/recognition and rewards and leadership were the TQM elements that had a positive association with TJS.

Practical implications

The outcomes of the study are of help to school principals and policy-makers in order to design and implement TQM policies that advance the quality of teaching and the effectiveness of processes in the primary and secondary education system, as well as to satisfy and motivate teachers for continuous improvement.

Originality/value

This was, to the best of our knowledge, the first study that has explored the impact of soft TQM elements on TJS.

Details

The TQM Journal, vol. 34 no. 5
Type: Research Article
ISSN: 1754-2731

Keywords

Content available
Article
Publication date: 1 December 2005

58

Abstract

Details

International Journal of Sustainability in Higher Education, vol. 6 no. 4
Type: Research Article
ISSN: 1467-6370

Article
Publication date: 1 February 1989

M.J. LE BAS and J. DURHAM

Scientific research is producing ever‐increasing amounts of quantitative data worthy of communication to scholars, but more than can be accommodated in refereed publications even…

Abstract

Scientific research is producing ever‐increasing amounts of quantitative data worthy of communication to scholars, but more than can be accommodated in refereed publications even though the number of journals is itself increasing. In the last twenty years, the quantity of geochemical analytical data produced world‐wide has increased a hundredfold or more. Geochemical and petrological journals nowadays rarely publish the complete sets of data; instead, only selected representative data are published and the remainder may or may not be put into supplementary publications. In the last five years, a scheme has been set up in the UK which co‐ordinates geochemical publications with a growing computerised geochemical data bank. The data bank comprises not only the geochemical analytical data actually printed on the journal pages but also the remainder of the data set pertaining to the published paper which could not be printed for lack of space. In collaboration with the journal editor, the data are collected into the data bank at the same time as the author is submitting his or her paper for publication. The author enters the data in a standard format and sends them as hard copy or in machine‐readable form to the data bank editor. The editor verifies the data and passes them for archiving to the National Geochemical Data Bank manager of the British Geological Survey whence they can be retrieved. The data are also relayed to the World Data Center for storage and further distribution.

Details

Journal of Documentation, vol. 45 no. 2
Type: Research Article
ISSN: 0022-0418

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