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Yuanfeng Zhu and Jun Meng
The purpose of this paper is to propose a physically plausible solution based on hybrid bounding volume (BV) hierarchy for real‐time collision detection (CD) and response between…
Abstract
Purpose
The purpose of this paper is to propose a physically plausible solution based on hybrid bounding volume (BV) hierarchy for real‐time collision detection (CD) and response between a deformable and a rigid object.
Design/methodology/approach
Hybrid BV can be used to build BV hierarchy for the deformable object. The overlapping tests based on separating axis theorem (SAT) can be used to deal with CD. The physics conception of restitution coefficient and other important forces can be used to more real collision response.
Findings
Many methods focus on a specific application, but none of them gives an approach to physically plausible, real‐time simulation of CD and response up to 10,000 of deforming primitives. The paper finds that hybrid BV AABB‐Sphere for deformable object could increase the efficiency for CD, and restitution coefficient and other important physical concepts could provide more real collision response.
Research limitations/implications
The paper does not deal with all types of CD, such as CD for two deformable objects.
Originality/value
Using AABB‐Sphere hybrid BV to build hierarchical BV tree for deformable object, and OBB‐Sphere hybrid BV for rigid object. Owing to the variety of hybrid BV structures, during different phases of CD, different overlapping tests are used to accelerate CD effectively. Using important physics conceptions provides a good solution to simulate more real collision response.
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Wei Li, Yang Zhang, Weidong Shi, Leilei Ji, Yongfei Yang and Yuanfeng Ping
This paper aims to study the transient flow characteristics in a mixed-flow pump during the start-up period.
Abstract
Purpose
This paper aims to study the transient flow characteristics in a mixed-flow pump during the start-up period.
Design/methodology/approach
In this study, numerical calculation of the internal flow field in a mixed-flow pump using the sliding mesh method was carried out. The regulation of the pressure, streamline and the relative speed during the start-up period was analyzed.
Findings
The trend of the simulated head is consistent with the experimental results, and the calculated head is around 0.3 m higher than the experimental head when the rotation speed reached the stable stage, indicating that the numerical method for the start-up process simulation of the mixed-flow pump has a high accuracy. At the beginning, the velocity inside the impeller changes little along the radius direction and the flow rate increases slowly during the start-up process. As the rotation speed reached the stable stage, the flow inside the impeller became steady, the vortex reduced and transient effects disappeared gradually.
Originality/value
The study results have significant value for revealing the internal unsteady flow characteristics of the mixed-flow pump and providing the reference for the design optimization of the mixed-flow pump.
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The Chinese civilization is an important part of the history of mankind. The purpose of this paper is to show that there are project management lessons to be learned from Chinese…
Abstract
Purpose
The Chinese civilization is an important part of the history of mankind. The purpose of this paper is to show that there are project management lessons to be learned from Chinese history, including that relating to the management of the building process in ancient China.
Design/methodology/approach
Through a review of the literature, this paper discusses the key management and economic practices in the building process of ancient China and highlights these practices from an important document, the Yingzao Fashi or (“Treatise on Architectural Methods”), that was compared with the modern‐day project management framework.
Findings
This paper explains the official systems instituted for public projects; the management of labour, design and planning of construction works; quantity surveying practices; the use, control and recycling of building materials; and inspection of building elements in ancient China.
Practical implications
The study suggests that lessons in the principles of construction project management in ancient China bear many similarities with the nine areas of modern‐day project management body of knowledge relating to integration, scope, time, cost, quality, human resource, communications, risk, and procurement management. An area for future research would be to compare the Yingzao Fashi with modern‐day codes of practice for building works to determine which of its “ancient” provisions relating to quality management are still relevant today.
Originality/value
It was found that much emphasis was placed by the ancient Chinese on the quality aspects of prominent building projects. This is one facet from which modern‐day project managers and clients can draw lessons.
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Yuanfeng Cai and Randall Shannon
The purpose of this paper is to identify underlying personal values that determine the mall shopping behaviour of Chinese consumers and to propose shopping intention as an…
Abstract
Purpose
The purpose of this paper is to identify underlying personal values that determine the mall shopping behaviour of Chinese consumers and to propose shopping intention as an additional mediator that enhances the value‐behaviour link.
Design/methodology/approach
A self‐administered web‐based survey with convenience sampling was used to collect the data. A structural equation modeling technique was used to test the proposed model.
Findings
Chinese mall shoppers' behaviours were found to be explained by value orientations which were both similar and different from their counterparts in the West. While Western mall shoppers are more likely to be directed by social affiliation and self‐actualising values in previous studies, Chinese mall shoppers are more likely to be influenced by self‐transcendence and self‐enhancement (similar to self‐actualising) values in the present study. Additionally, shopping intention was found to improve the predictive power of consumers' attitude toward mall attributes in terms of shopping frequency and money spent in the mall.
Research limitations/implications
The main limitation of this study is related to measurement error, derived from using simplified instruments to measure personal values. In addition, both personal values and attitudes are abstract constructs, which are difficult to measure; therefore this may also contribute to a larger error variance.
Practical implications
The results of this study are especially beneficial for mall developers and retailers for crafting effective positioning strategies and guiding their communication strategies in the China market.
Originality/value
The proposed model makes a theoretical contribution by testing a Western theory in a non‐Western context. In addition, the proposed model helps researchers better understand the value‐behaviour relationship in a more comprehensive framework.
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Hakan Hafizoglu, Huseyin Emrah Konokman, Latif Kesemen and Ali Kursat Atay
This paper aims to investigate the effects of fragment impacts to shaped charge warheads in terms of shaped charge jet formation geometries and penetration performances.
Abstract
Purpose
This paper aims to investigate the effects of fragment impacts to shaped charge warheads in terms of shaped charge jet formation geometries and penetration performances.
Design/methodology/approach
In experimental process, a fragment was accelerated to a shaped charge warhead by means of a powder gun to a velocity more than 1,000 m/s, and this impact led to conical damage in the explosive of the warhead. Deformation on the warhead was visualized using X-ray technique to observe holes generated during fragment impact. Penetration test was performed against AISI 1040 steel plates with the damaged shaped charge warhead. Penetration performance of shaped charge jet, which deviated from the symmetry axis, was simulated by using SPEED software with 3-D Eulerian method to validate the numerical modelling method by comparing penetration test and simulation results of damaged warhead.
Findings
Simulation and test results showed good correlation for the warhead in terms of penetration depth and hole geometry at the impact surface of steel plates. In addition, the effects of the numbers and the geometries of fragment holes on shaped charge jet penetration performances were investigated with validated numerical methods. Simulation results showed that the increase in the number of fragment holes in the explosive of the warhead led to particulation of shaped charge jet that diminished penetration depth in the target plate. Additionally, simulation results also showed that the fragment hole geometry in the explosive after different fragment impact angles affected the amount of jet deviation from the symmetry axis as well as penetration depth in the target plate.
Practical implications
The results obtained from the current study revealed that fragment impact angle and different number of fragment impact reduced the penetration performance of shaped charge warhead by influencing the symmetry of shaped charge jet negatively.
Originality/value
The current study fulfils the need to investigate how fragment impact on the shaped charge warhead affect the formation symmetry of shaped charge jet as well as penetration performance by experimental and numerical methods. Penetration performance result of asymmetric jet is compared by experimental and numerical studies. A detailed methodology on numerically modelling of the effect of fragment impact angle and number of fragment impact on shaped charge jet performance is given in this study.
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Wei Li, Yuxin Huang, Leilei Ji, Lingling Ma and Ramesh Agarwal
The purpose of this study is to explore the transient characteristics of mixed-flow pumps during startup process.
Abstract
Purpose
The purpose of this study is to explore the transient characteristics of mixed-flow pumps during startup process.
Design/methodology/approach
This study uses a full-flow field transient calculation method of mixed-flow pump based on a closed-loop model.
Findings
The findings show the hydraulic losses and internal flow characteristics of the piping system during the start-up process.
Research limitations/implications
Large computational cost.
Practical implications
Improve the accuracy of current numerical simulation results in transient process of mixed-flow pump.
Originality/value
Simplify the setting of boundary conditions in the transient calculation.
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Verona Ramas Joseph and Nur Kamaliah Mustaffa
The demand to reduce carbon emissions has become an increasingly important social factor due to the unprecedented impacts of climate change. However, most existing publications…
Abstract
Purpose
The demand to reduce carbon emissions has become an increasingly important social factor due to the unprecedented impacts of climate change. However, most existing publications have focused on minimizing emissions during the operational phase of buildings. At the same time, there is a lack of comprehensive research conducted on carbon emissions, specifically during the construction phase. The purpose of this paper is to identify, review and classify current practices related to carbon emissions management in construction operations to gain greater insight into how to reduce and mitigate emissions and achieve more sustainable solutions.
Design/methodology/approach
This study reviewed the published literature on carbon emissions from construction. A total of 198 bibliographic records were extracted from the Scopus collection database and analyzed using Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). PRISMA is used as a basis for reporting possible trends, research methods and strategies used in published literatures. A total of 99 papers related to carbon emissions in the construction operations were further reviewed and analyzed. This review paper draws on existing research and identifies current carbon management patterns in construction projects.
Findings
Data indicated an upward trend in the number of publications in carbon emissions research during the last few years, particularly in 2015, 2017 and 2019. The most significant contributions to the domain were reported from China, Europe and the USA. This paper found that most studies conduct the Life Cycle Assessment (LCA) method to estimate carbon emissions. This paper found that the primary studies have focused on construction machinery and equipment emissions. The strategies such as establishing uniform standards for carbon emissions policies and regulations, equipment and logistic planning and low carbon design material will potentially impact carbon emissions reductions.
Practical implications
This paper provides information that will be beneficial for the construction industry to design and manage construction operations. It will also be of interest to those looking to reduce or manage construction emissions.
Originality/value
Although there is a diversity of current thinking related to the practical estimation and management of carbon emissions in construction projects, there is no consolidated set of keys of standardized carbon emissions management in practice. By assessing the existing paradigms of carbon assessment methods and tactics in the construction industry, this study contributed to the existing knowledge base by providing insights into current techniques in the construction sector for monitoring and mitigating emissions.