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Article
Publication date: 17 October 2008

Kong Yushou, Ji Lingling, Wang Changyu, Li Liguo and Zeng Liming

To forecast the path of tropic cyclones by using a non‐linear statistical forecasting technique – the method of successive analogy.

1279

Abstract

Purpose

To forecast the path of tropic cyclones by using a non‐linear statistical forecasting technique – the method of successive analogy.

Design/methodology/approach

Non‐linear statistical forecasting models can describe the non‐linear relationship between the factors and the forecasting objects and the real atmospheric movement more accurately, so they usually have stronger forecasting capability. In practice, however, it is shown that the relationships between predictors and predictands sometimes are so complex that it is very difficult or even impossible to establish the kind of non‐linear mathematical model. Therefore, it is an important topic for atmospheric science to solve non‐linear prediction problem of atmospheric systems by using the non‐function model approach.

Findings

The objective and quantitative prediction of tropical cyclone moving path can be given by using the method of successive analogy, a non‐linear forecasting technique, and calculating the similarity parameters between the grayscale field and the height field.

Research limitations/implications

Further experiments are needed to verify this technique.

Practical implications

A very useful technique for solving non‐linear problem.

Originality/value

Illustrates the new technique of solving non‐linear statistic problem and its application.

Details

Kybernetes, vol. 37 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

Open Access
Article
Publication date: 19 March 2024

Feng Chen, Zhongjin Wang, Dong Zhang and Shuai Zeng

Explore the development trend of chemically-improved soil in railway engineering.

Abstract

Purpose

Explore the development trend of chemically-improved soil in railway engineering.

Design/methodology/approach

In this paper, the technical standards home and abroad were analyzed. Laboratory test, field test and monitoring were carried out.

Findings

The performance design system of the chemically-improved soil should be established.

Originality/value

On the basis of the performance design, the test methods and standards for various properties of chemically-improved soil should be established to evaluate the improvement effect and control the engineering quality.

Details

Railway Sciences, vol. 3 no. 2
Type: Research Article
ISSN: 2755-0907

Keywords

Article
Publication date: 1 January 2024

Shi Chen, Zhiyong Han, Qiang Zeng, Bing Wang, Liming Wang, Liuyang Guo and Yimin Shao

Hydro-viscous drive (HVD) clutches are widely used in equipment requiring soft start, such as fans and pumps, to transmit torque and adjust speed by changing the gap distance…

104

Abstract

Purpose

Hydro-viscous drive (HVD) clutches are widely used in equipment requiring soft start, such as fans and pumps, to transmit torque and adjust speed by changing the gap distance between friction pairs. This paper aims to propose a novel two-parameter evaluation method for HVD during the mixed lubrication stage. The objective is to develop an effective model that establishes the relationship between these parameters and the actual surface topography.

Design/methodology/approach

In the presented methods, the fractal features of the real manufacturing surface are calculated based on the power spectrum function by the ultra-depth three-dimensional microscope. After that, the hybrid friction model of the friction plate is established based on mixed elasto-hydrodynamic lubrication theory, boundary friction model and fractal theory. Then the torque and load bearing characteristics of the clutch are obtained, and the influences of the surface fractal features are investigated and discussed. Finally, the Weierstrass–Mandelbrot function is adopted for the surface topography characterization and evaluation.

Findings

The results indicate that the proposed method exhibits good accuracy, while the speed difference between the friction pair exceeds 2,500 rpm. It is concluded that this paper proposed a way to evaluate the torque and loading capacity of HVD considering the real manufacturing surface topography and is helpful for surface optimization.

Originality/value

The originality and value of this study lie in its development of a novel torque and load bearing capacity evaluation method for HVD in mixed lubrication stage, considering manufacturing surface topography and describing the real manufacturing surface.

Details

Industrial Lubrication and Tribology, vol. 76 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 19 February 2024

Xiang Shen, Kai Zeng, Liming Yang, Chengyong Zhu and Laurent Dala

This paper aims to study passive control techniques for transonic flow over a backward-facing step (BFS) using square-lobed trailing edges. The study investigates the efficacy of…

Abstract

Purpose

This paper aims to study passive control techniques for transonic flow over a backward-facing step (BFS) using square-lobed trailing edges. The study investigates the efficacy of upward and downward lobe patterns, different lobe widths and deflection angles on flow separation, aiming for a deeper understanding of the flow physics behind the passive flow control system.

Design/methodology/approach

Large Eddy Simulation and Reynolds-averaged Navier–Stokes were used to evaluate the results of the study. The research explores the impact of upward and downward patterns of lobes on flow separation through the effects of different lobe widths and deflection angles. Numerical methods are used to analyse the behaviour of transonic flow over BFS and compared it to existing experimental results.

Findings

The square-lobed trailing edges significantly enhance the reduction of mean reattachment length by up to 80%. At Ma = 0.8, the up-downward configuration demonstrates increased effectiveness in reducing the root mean square of pressure fluctuations at a proximity of 5-step height in the wake region, with a reduction of 50%, while the flat-downward configuration proves to be more efficient in reducing the root mean square of pressure fluctuations at a proximity of 1-step height in the near wake region, achieving a reduction of 71%. Furthermore, the study shows that the up-downward configuration triggers early spanwise velocity fluctuations, whereas the standalone flat-downward configuration displays less intense crosswise velocity fluctuations within the wake region.

Practical implications

The findings demonstrate the effectiveness of square-lobed trailing edges as passive control techniques, showing significant implications for improving efficiency, performance and safety of the design in aerospace and industrial systems.

Originality/value

This paper demonstrates that the square-lobed trailing edges are effective in reducing the mean reattachment length and pressure fluctuations in transonic conditions. The study evaluates the efficacy of different configurations, deflection angles and lobe widths on flow and provides insights into the flow physics of passive flow control systems.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 8 September 2022

Johnny Kwok Wai Wong, Mojtaba Maghrebi, Alireza Ahmadian Fard Fini, Mohammad Amin Alizadeh Golestani, Mahdi Ahmadnia and Michael Er

Images taken from construction site interiors often suffer from low illumination and poor natural colors, which restrict their application for high-level site management purposes…

Abstract

Purpose

Images taken from construction site interiors often suffer from low illumination and poor natural colors, which restrict their application for high-level site management purposes. The state-of-the-art low-light image enhancement method provides promising image enhancement results. However, they generally require a longer execution time to complete the enhancement. This study aims to develop a refined image enhancement approach to improve execution efficiency and performance accuracy.

Design/methodology/approach

To develop the refined illumination enhancement algorithm named enhanced illumination quality (EIQ), a quadratic expression was first added to the initial illumination map. Subsequently, an adjusted weight matrix was added to improve the smoothness of the illumination map. A coordinated descent optimization algorithm was then applied to minimize the processing time. Gamma correction was also applied to further enhance the illumination map. Finally, a frame comparing and averaging method was used to identify interior site progress.

Findings

The proposed refined approach took around 4.36–4.52 s to achieve the expected results while outperforming the current low-light image enhancement method. EIQ demonstrated a lower lightness-order error and provided higher object resolution in enhanced images. EIQ also has a higher structural similarity index and peak-signal-to-noise ratio, which indicated better image reconstruction performance.

Originality/value

The proposed approach provides an alternative to shorten the execution time, improve equalization of the illumination map and provide a better image reconstruction. The approach could be applied to low-light video enhancement tasks and other dark or poor jobsite images for object detection processes.

Details

Construction Innovation , vol. 24 no. 2
Type: Research Article
ISSN: 1471-4175

Keywords

Book part
Publication date: 30 November 2020

Aysen Ercan İştin

The discovery of internet technologies which is one of the most important developments of the twenty-first century has enabled individuals and institutions to overcome…

Abstract

The discovery of internet technologies which is one of the most important developments of the twenty-first century has enabled individuals and institutions to overcome geographical and time constraints creating fundamental changes in communication. As a result, online communities have enabled people to meet the internet for various reasons such as seeking and sharing information, discuss community issues and ask questions; and online communities have also enabled businesses and consumers to connect with each other at any time. Especially the emergence of Internet-based social media technologies such as blogs, virtual communities, wikis, social networks, YouTube, Facebook and Instagram provides tourists to share their travel experiences. Information shared on social media sites is considered to be an important source of information that can help tourists’ travel plan and may even influence the travel decisions of potential tourists. In this context, the concept of social media in tourism businesses has been examined in the research. Within the framework of the research, it has been observed that social media has influenced the tourists’ behavior regarding travel motivations in the context of various motivations (having information about destinations, hotels, services of hotels, wondering about consumers’ experiences who were in touristic consumption before, etc.). It is also among other findings that social media has increased the overtourism crisis.

Details

The Emerald Handbook of ICT in Tourism and Hospitality
Type: Book
ISBN: 978-1-83982-689-4

Keywords

Open Access
Article
Publication date: 1 April 2021

Xinyi Hong, Chenguang Li, Junfei Bai, Zhifeng Gao and Liming Wang

Following the standard practice of using nutrition claims to denote food functionality, this study empirically explores Chinese consumers’ willingness-to-pay for functional…

2125

Abstract

Purpose

Following the standard practice of using nutrition claims to denote food functionality, this study empirically explores Chinese consumers’ willingness-to-pay for functional processed meat products by using three nutrition claims (namely “increased calcium,” “containing omega-3”, and “reduced salt”) made on pork sausages. It also aims to outline the typical characteristics of Chinese consumer segments based on preferences.

Design/methodology/approach

A choice-based choice experiment is utilized to investigate Chinese consumers’ valuation on attributes of interest regarding functional sausage products. First-hand data was collected in the two cities of Xi'an and Beijing.

Findings

There are market potentials for domestic and/or imported functional processed meat products among Chinese consumers. Nutrition claims made on pork sausages are appealing to Chinese consumers, and therefore, monetarily rewarded by them. Being imported from a more developed country of origin could both positively and negatively impact consumers’ WTP for nutrition claims made on pork sausages. Furthermore, specific functional modification strategies should be taken into account when addressing different segments of the Chinese market. In addition, regional impacts between Xi'an and Beijing are implied in terms of consumers’ valuation for functional pork sausages.

Research limitations/implications

Limitations in the current study are mainly two folds. First, the WTP estimation magnitudes are subject to a hypothetical bias by using a stated preference approach. Second, this study only focuses on pork sausages to explore consumers’ perceptions and selects three nutrition claims among many other relevant options.

Practical implications

Implications are provided for meat marketers and for Chinese official food policymakers, such that promoting meat products with a nutrition claim is an attractive marketing strategy for foreign food manufacturers in China, and more reformulated meat products with better nutritional compositions should be allowed in the Chinese market.

Originality/value

To the best of the author’s knowledge, this research is the first to fill in the literature blank on investigating the consumers’ valuation for functional meat in the emerging market of China. Because when taking Chinese consumers as a target market and evaluating their perceptions of food quality-related labeling and certifications, the existing literature is mainly limited to topics of product safety, organic/green products, and geographical origins. However, nutrition claims, as marketable credence attributes that associate closely to the main characteristics of the functional food products, have been explored to a much lesser extent among Chinese consumers.

Details

China Agricultural Economic Review, vol. 13 no. 2
Type: Research Article
ISSN: 1756-137X

Keywords

Article
Publication date: 8 February 2011

Xun Wang, Yongchang Liu, Liming Yu, Zhizhong Dong and Zhiming Gao

The purpose of this paper is to study the relationship between microstructure and mechanical properties of Sn‐4.0Bi‐3.7Ag‐0.9Zn (in wt%) solder, and the structural evolution of…

Abstract

Purpose

The purpose of this paper is to study the relationship between microstructure and mechanical properties of Sn‐4.0Bi‐3.7Ag‐0.9Zn (in wt%) solder, and the structural evolution of the soldered interfaces.

Design/methodology/approach

The solder was prepared by a vacuum arc furnace. Scanning electron microscopy (SEM) and X‐ray diffraction were used to identify the microstructure and composition. The melting temperature, microhardness and tensile strength were measured. Solder joints were prepared by reflowing at 250°C for 1 min in a vacuum oven and the soldered interfaces were observed by using SEM.

Findings

The microstructure of the slowly cooled Sn‐4.0Bi‐3.7Ag‐0.9Zn specimen is composed of bulk Ag3Sn, AgZn intermetallic compounds (IMCs), Bi precipitates and a β‐Sn phase. The developed solder exhibits good comprehensive properties, such as low‐melting temperature, high microhardness and ultimate tensile strength. A complicated IMC layer forms at the interface with Cu pads and it turns into a thinner Ni3Sn4 layer with Ni/Cu substrates.

Originality/value

The paper shows how a high performance, lead‐free solder was developed.

Details

Soldering & Surface Mount Technology, vol. 23 no. 1
Type: Research Article
ISSN: 0954-0911

Keywords

Book part
Publication date: 5 June 2023

Shima Yazdani and Esmail Lakzian

Currently, waste is regarded as a symptom of inefficiency. The generation of waste is a human activity, not a natural one. Currently, landfilling and incinerating wastes are…

Abstract

Currently, waste is regarded as a symptom of inefficiency. The generation of waste is a human activity, not a natural one. Currently, landfilling and incinerating wastes are common waste management techniques; but the use of these methods, in addition to wasting raw materials, causes damage to the environment, water, soil, and air. In the new concept of “Zero Waste” (ZW), waste is considered a valuable resource. A vital component of the methodology includes creating and managing items and procedures that limit the waste volume and toxicity and preserve and recover all resources rather than burning or burying them. With ZW, the end of one product becomes the beginning of another, unlike a linear system where waste is generated from product consumption. A scientific treatment technique, resource recovery, and reverse logistics may enable the waste from one product to become raw material for another, regardless of whether it is municipal, industrial, agricultural, biomedical, construction, or demolition. This chapter discusses the concept of zero landfills and zero waste and related initiatives and ideas; it also looks at potential obstacles to put the ZW concept into reality. Several methods are presented to investigate and evaluate efficient resource utilization for maximum recycling efficiency, economic improvement through resource minimization, and mandatory refuse collection. One of the most practical and used approaches is the Life Cycle Assessment (LCA) approach, which is based on green engineering and the cradle-to-cradle principle; the LCA technique is used in most current research, allowing for a complete investigation of possible environmental repercussions. This approach considers the entire life cycle of a product, including the origin of raw materials, manufacturing, transportation, usage, and final disposal, or recycling. Using a life cycle perspective, all stakeholders (product designers, service providers, political and legislative agencies, and consumers) may make environmentally sound and long-term decisions.

Details

Pragmatic Engineering and Lifestyle
Type: Book
ISBN: 978-1-80262-997-2

Keywords

Article
Publication date: 1 August 1999

Jaroslav Mackerle

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper…

2620

Abstract

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Details

Engineering Computations, vol. 16 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

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