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This paper aims to address the numerical simulation of additive manufacturing (AM) processes. The numerical results are compared with the experimental campaign carried out at State Key Laboratory of Solidification Processing laboratories, where a laser solid forming machine, also referred to as laser engineered net shaping, is used to fabricate metal parts directly from computer-aided design models. Ti-6Al-4V metal powder is injected into the molten pool created by a focused, high-energy laser beam and a layer of added material is sinterized according to the laser scanning pattern specified by the user.

The numerical model adopts an apropos finite element (FE) activation technology, which reproduces the same scanning pattern set for the numerical control system of the AM machine. This consists of a complex sequence of polylines, used to define the contour of the component, and hatches patterns to fill the inner section. The full sequence is given through the common layer interface format, a standard format for different manufacturing processes such as rapid prototyping, shape metal deposition or machining processes, among others. The result is a layer-by-layer metal deposition which can be used to build-up complex structures for components such as turbine blades, aircraft stiffeners, cooling systems or medical implants, among others.

Ad hoc FE framework for the numerical simulation of the AM process by metal deposition is introduced. Description of the calibration procedure adopted is presented.

The objectives of this paper are twofold: firstly, this work is intended to calibrate the software for the numerical simulation of the AM process, to achieve high accuracy. Secondly, the sensitivity of the numerical model to the process parameters and modeling data is analyzed.

This paper aims to investigate the tribological behavior and online infrared spectra of three types of lubricating oils containing dinonyl diphenylamine (DNDA) antioxidant, which are mineral oil (MO), poly alpha olefin (PAO) and trimethylolpropane trioleate (TMPTO), during the friction process at high temperature (temperature rising at first and isothermal holding afterwards).

A platform of low speed four-ball tribometer equipped with a temperature controller combined with infrared spectrometer was established. MO, PAO and TMPTO base oils were mixed with 1.0 Wt.% DNDA antioxidant, coded as MO_a, PAO_a and TMPTO_a in sequence. The friction coefficient and online infrared spectra of the oils were tested during the friction process of temperature rising at first and isothermal holding afterwards, and the wear tracks of the upper balls were measured using a confocal scanning optical microscope.

The results indicated that the DNDA antioxidant was depleted to reduce the generation of alcohols and carbonyl products, and the depletion rate of DNDA followed the sequence of MO_a > PAO_a > TMPTO_a. In the temperature rising friction process, the critical transition of friction coefficient was confirmed. The addition of DNDA antioxidant reduced the temperature of the oils at the critical transition of friction coefficient, and the temperature followed the sequence of TMPTO_a > PAO_a > MO_a. After the critical transition, the friction coefficient was first increased and then declined to a steady value; the friction coefficient of MO_a increased and declined first, followed by PAO_a and TMPTO_a. In the steady stage of friction, there was no obvious effect of DNDA on the friction coefficient of the oils. Moreover, DNDA enhanced the wear properties of MO_a and PAO_a; no obvious improvement was revealed for the wear property of TMPTO_a.

The established platform of low speed four-ball tribometer combined with infrared spectrometer successfully realized online testing of the structure changes of lubricating oil during high temperature friction, which can give some reference on the oxidation and friction researches of lubricating oil.

This paper aims to investigate the thermal oxidation characteristics of the unsaturated bonds (C=C) of trimethylolpropane trioleate (TMPTO) and to reveal the high temperature oxidation decay mechanism of unsaturated esters and the nature of the anti-oxidation properties of the additives.

Using a DXR laser microscopic Raman spectrometer and Linkam FTIR600 temperature control platform, the isothermal oxidation experiments of TMPTO with or without 1.0 wt. % of different antioxidants were performed.

The results indicated that the Raman peaks of =C-H, C=C and -CH₂- weaken gradually with prolonged oxidation time, and the corresponding Raman intensities drop rapidly at higher temperatures. The aromatic amine antioxidant can decrease the attenuation of peak intensity, as it significantly reduces the rate constant of C=C thermal oxidation. The hindered phenolic antioxidant has a protective effect during the early stages of oxidation (induction period), but it may accelerate the oxidation of C=C afterwards.

Research on the structure changes of synthetic esters during oxidation by Raman spectroscopy will be of great importance in promoting the use of Raman spectroscopy to analyze the oxidation of lubricants.

The 2019 novel coronavirus (COVID-19) pandemic has affected many countries around the world. Due to the debate on the source of the outbreak, wildlife meat consumption has gained international attention and become an area that requires further exploration. The purpose of this research is to explore the differences in game consumption motivations and behaviours among populations in northern and southern China.

An online survey on wild meat awareness with (potential) game consumers across the country as target groups was conducted.

Results from this study showed that consumers in the southern region have a preference for wildlife. This preference was determined by factors such as natural environment, history and culture and the level of economic development. However, there was no significant difference in the frequency of game consumption between the north and south since game meat is not a major component of the daily diet.

The government should consider banning this trade permanently to prevent future disease outbreaks caused by wildlife-to-human transmissions.

The consumption of game meat is regional, but the animals in game trades live across a wider area, and thus, game trades have a global influence on ecological systems and human health. Therefore, this epidemic is also a global concern, which might lead people to display a highly negative attitude towards consuming game meat.

It is challenging to derive an appropriate tolerance relation for tolerance rough set-based classifiers (TRSCs). The traditional tolerance rough set employs a simple distance function to determine the tolerance relation. However, such a simple function does not take into account criterion weights and the interaction among criteria. Further, the traditional tolerance relation ignores interdependencies concerning direct and indirect influences among patterns. This study aimed to incorporate interaction and interdependencies into the tolerance relation to develop non-additive grey TRSCs (NG-TRSCs).

For pattern classification, this study applied non-additive grey relational analysis (GRA) and the decision-making trial and evaluation laboratory (DEMATEL) technique to solve problems arising from interaction and interdependencies, respectively.

The classification accuracy rates derived from the proposed NG-TRSC were compared to those of other TRSCs with distinctive features. The results showed that the proposed classifier was superior to the other TRSCs considered.

In addition to pattern classification, the proposed non-additive grey DEMATEL can further benefit the applications for managerial decision-making because it simplifies the operations for decision-makers and enhances the applicability of DEMATEL.

This paper contributes to the field by proposing the non-additive grey tolerance rough set (NG-TRS) for pattern classification. The proposed NG-TRSC can be constructed by integrating the non-additive GRA with DEMATEL by using a genetic algorithm to determine the relevant parameters.

Given the important role of knowledge resource for organizational innovation, the purpose of this study is to examine the mediating mechanism of knowledge management capability (KMC) and the moderating role of knowledge-centered culture (KCC) in the relationship between human resource management (HRM) and firms’ innovation capabilities.

Analysis of moment structures and structural equation modeling are applied to examine the correlation among the constructs based on the survey data collected from 135 manufacturing firms.

The empirical findings reveal that KMC positively mediates the relationship between HRM practices and innovation capability. Especially, KCC of organization significantly fosters the impacts of HRM practices on KMC and aspects of innovation capability, namely, exploitative and exploratory innovation.

Chinese firms should invest in HRM practices and KMC to improve their innovation capabilities. In addition, developing KCC is suitable for Chinese firms to foster the effects of HRM practice on innovation capability.

By investigating the different moderated-mediation mechanisms, the paper has significantly contributed to advancing the body of knowledge of innovation theory and providing deeper insights on the correlation between HRM practices and firm’s capability for ambidextrous innovations.

This paper aims to further develop stator permanent magnet (PM) type memory machines by providing generalized design guidelines for double-stator memory machines (DSMMs) with hybrid PMs. This paper discusses the design experience of DSMMs and presents a comparative study of radial magnetization (RM) and circumferential magnetization (CM) types.

It begins with an introduction to RM and CM operating principles and magnetization mechanisms. Then, a comparative study is conducted for one of the RM-DSMM rotor pole pairs, inner and outer stator clamping angles and low coercive force PMs thickness. Finally, the two machines’ finite element simulation performance is compared. The validity of the proposed machine structure is demonstrated.

In this paper, the double-stator structure is extended to parallel hybrid PM memory machines, and two novel DSMMs with RM and CM configurations are proposed. Two types of DSMMs have PMs and magnetizing windings on the inner stator and armature windings on the outer stator. The main difference between the two is the arrangement of PMs on the inner stator.

Conventional stator PM memory machines have geometrical space conflicts between the PM and armature windings. The proposed double-stator structure can alleviate these conflicts and increase the torque density accordingly. In addition, this paper contributes to comparing the arrangement of hybrid PMs for DSMMs.

This study clarifies how intra-organizational social capital (IOSC) and unit-organizational ambidexterity (UOA), using resource-based view and dynamic capability theory, together support organizational value creation. While there is research in strategic human resource management (SHRM) exploring the role of resources and its uses, there remains limited understanding of how resources are linked and their effective utilization in the service sector. This study aims to examine the mediating process linking employee-experienced service-oriented high-performance work systems (SHPWS) experienced by employees and service performance by integrating IOSC and UOA.

This study uses time lagged data from managers and employees of different branches of Chinese state-owned banks. To test the proposed hypotheses, path analysis was applied.

The path analysis results reveal that employee-experienced SHPWS is an important antecedent of service performance. Moreover, IOSC (as resources) and UOA (uses) strongly mediate the theorized relationship.

This study attempts to refine theory and practice with clearer, more insightful and coherent means to better understand and help unpack the ‘black box’ between SHPWS-performance relationships through a new linkage model.

China is a critical factor for constructing an all-round well-off society. Infrastructure construction, especially high-grade highways, in the western area is an essential component of the strategy for large-scale development of west China. It is crucial to evaluate investment projects for high-grade highways and select the best one. Testing investment projects and selecting the best one can be recognized as a multicriteria decision-making (MCDM) problem. In this process, decision-makers (DMs) usually face with uncertain information because of complicated decision environment or their limited knowledge.

A new Evaluation based on the Distance from Average Solution (EDAS) for PFS based on the DEMATEL is proposed: The authors offer a new score function and prove some properties for the score function. They put forward a novel Decision-making Trial and Evaluation Laboratory (DEMATEL) method for PFS to analyze the relations of criteria and get criteria weights. Considering the bounded rationality of DM, the authors propose a new EDAS method for PFS based on prospect theory. They apply their proposed approach to a western city's actual case in selecting a suitable project for building a high-grade highway.

By comparison, the authors can observe that our method has some traits: (1) considering bounded rationality of DM; (2) fewer computation; (3) having the ability to obtain the relation of criteria and finding the critical factor in the decision system.

In this paper, the authors propose a new EDAS method for PFS based on the DEMATEL technique. They transform PFS into crisp numbers by their proposed new score function for PFN to make the decision process more convenient. Then, the authors use the DEMATEL method to obtain the relationship between criteria and criteria weights. Furthermore, they propose a new EDAS method for PFS based on DEMATEL to reduce the computational complexity. Finally, they apply our method to a real case and compare our method with two traditional methods.

This study aims to identify key supply chain challenges and opportunities of the case of Hong Kong toy manufacturing company during the COVID-19 outbreak and develop a comprehensive structural relationship to rank them.

In this study, a toy model company in Hong Kong is considered to discuss about what challenges and opportunities have the biggest impacts on non-necessary goods companies and how to deal with different impacts on entire supply chain flow disruption during COVID-19. A semi-structured interview with five decision-makers from the company was made to give key challenges and opportunities scores. The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) technique is used to establish the model and rank them afterward to overcome the challenges.

From the data analysis and results, “salary of employee” and “inconvenient transportation” have emerged as top and bottom key challenges respectively. The sequence of organized challenges in the list needs to mitigate one by one in this order to improve the supply chain performance. The “client's orders’ frequency, customer management” and “supplier/partner relationship management” are identified as the top and bottom respectively to develop the opportunities.

These key challenges and opportunities are identified as contributing attributes and provide the way to measure to improve production, profits and sustainable growth of the toy manufacturing company during a pandemic. Moreover, it helps to improve the distribution level and good planning with appropriate decision making to manage the supply chain performance considering humanitarian aspects during a pandemic outbreak.

The novelty of this study is to identify the key supply chain challenges and opportunities measured by the TOPSIS method to rank them and consider the case of a Hong Kong toy manufacturing company as a case-based approach to measuring its performance during the COVID-19 outbreak.