The problem of cyclic variation has been an interesting area of research and has been investigated by many researchers. It is more severe in the case of two‐stroke engines…
Abstract
Purpose
The problem of cyclic variation has been an interesting area of research and has been investigated by many researchers. It is more severe in the case of two‐stroke engines compared with four‐stroke engines. One of the reasons for these cycle‐to‐cycle variations is the variations in the air‐fuel ratios of individual cycles and, if these values of individual cycle air‐fuel ratios are available by some means, they can be used for controlling the cyclic variations. The purpose of this paper is to find a technique to predict the air‐fuel ratio of the individual cycles and use the same for reducing cyclic variations.
Design/methodology/approach
In this work, a neuro‐fuzzy model was developed using MATLAB software to compute the air‐fuel ratio of the individual cycles based on the relationship between the air‐fuel ratio and the combustion parameters such as those indicating mean effective pressure (IMEP), crank angle occurrence of peak pressure, and angles of different percentages of heat releases. In‐cylinder pressure traces of 1,000 continuous cycles were measured using a Personal Computer (PC)‐based data acquisition system and an investigation was carried out. The readings were taken for two modes of operations, namely gasoline carburetion and electronic gasoline injection. The engine was loaded by an eddy current dynamometer. The air‐fuel ratio was varied from rich to lean by adjusting the fuel quantity in the carburetion mode and adjusting the pulse width (measure of quantity of fuel to be injected) in the injection mode, at constant throttle. The cyclic variation was identified by the variations in the peak pressures and IMEPs of the individual cycles. The stored data were given as input to the developed neuro‐fuzzy model and, using SIMULINK, the air‐fuel ratios of individual cycles were obtained. These predicted values are fed to the electronic control module (ECM) (meant for injecting the fuel) for refining the pulse width to get cyclic variations reduced.
Findings
Results show that cyclic variation increases when the mixture becomes lean. It was also found that cyclic variation in an injected engine was less in comparison with the carbureted engine, as the precise control of air‐fuel mixture was possible in the case of the injected engine.
Research limitations/implications
The technique used in this work may be modified to give more precise pulse width by incorporating various other parameters like exhaust temperature, etc. Future research may be focused to incorporate this system in a moving vehicle to get more fuel efficiency and fewer emissions.
Practical implications
The design of vehicle and engine should be slightly modified to incorporate the ECM and various sensors.
Originality/value
The originality in this paper is that a new technique was developed to find the air‐fuel ratio of individual cycles. This will be useful for the engine manufacturers and for those researchers doing research on the engine side.
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Junying Liu, Zhipeng Cui, Yingbin Feng, Srinath Perera and Jie Han
Cultural differences have been frequently cited as a major source of risks for international joint ventures (IJVs). Cultural differences may cause extensive conflicts in…
Abstract
Purpose
Cultural differences have been frequently cited as a major source of risks for international joint ventures (IJVs). Cultural differences may cause extensive conflicts in technology, norms and emotion among the international joint venture (IJV) partners. The purpose of this study is to explore the interactive effects of national culture differences (NCDs) and conflict management approaches on the performance of international construction joint ventures (ICJV).
Design/methodology/approach
Data were collected using a questionnaire survey method with 143 valid responses. Partial least squares structural equation modeling (PLS-SEM) was used to test the research hypotheses.
Findings
It was found that ICJV performance declined with a high degree of NCDs. The negative effect of NCDs on ICJV performance was mitigated by adopting the cooperative conflict management approach; while it was aggravated by adopting the competitive conflict management approach. The findings may provide an alternative way (i.e. adopting the cooperative conflict management approach rather than avoiding or competitive approaches) to address the cultural conflicts in the multicultural project management teams.
Practical implications
Firstly, as NCD negatively impacts performance of ICJVs, project managers should pay attention to cultural issues and learn how to manage them; Secondly, as cooperative and competitive conflict management approaches have different moderating effects on the relationship between NCD and ICJV performance, project managers must choose appropriate conflict management styles in multination teams. Thirdly, as the avoiding approach has no significant moderating effect on the negative relationship between NCD and ICJV performance, it is important for Chinese partners not to employ avoiding approach to deal with conflicts in ICJV.
Originality/value
This study uniquely adds to the literature on cultural issues in managing ICJVs by integrating the moderating effects of conflict management approaches. The interactive effects of conflict management approaches and national cultural differences on ICJV project performance may contribute to the theories regarding conflict management theory in the context of cross-cultural management.
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Isil Yazar, Tolga Yasa and Emre Kiyak
An aircraft engine control system consists of a large scale of control parameters and variables because of the complex structure of aero-engine. Monitoring and adjusting control…
Abstract
Purpose
An aircraft engine control system consists of a large scale of control parameters and variables because of the complex structure of aero-engine. Monitoring and adjusting control variables and parameters such as detecting, isolating and reconfiguring the system faults/failures depend on the controller design. Developing a robust controller is based on an accurate mathematical model.
Design/methodology/approach
In this study, a small-scale turboprop engine is modeled. Simulation is carried out on MATLAB/Simulink for design and off-design operating conditions. Both steady-state and transient conditions (from idle to maximum thrust levels) are tested. The performance parameters of compressor and turbine components are predicted via trained Neuro-Fuzzy model (ANFIS) based on component maps. Temperature, rotational speed, mass flow, pressure and other parameters are generated by using thermodynamic formulas and conservation laws. Considering these calculated values, error calculations are made and compared with the cycle data of the engine at the related simulation conditions.
Findings
Simulation results show that the designed engine model’s simulation values have acceptable accuracy for both design and off-design conditions from idle to maximum power operating envelope considering cycle data. The designed engine model can be adapted to other types of gas turbine engines.
Originality/value
Different from other literature studies, in this work, a small-scale turboprop engine is modeled. Furthermore, for performance prediction of compressor and turbine components, ANFIS structure is applied.
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The paper is a review of current research on phytochemicals and how they may alleviate type 2 diabetes by improving insulin activity in the body.
Abstract
Purpose
The paper is a review of current research on phytochemicals and how they may alleviate type 2 diabetes by improving insulin activity in the body.
Design/methodology/approach
Literature searches were conducted to find a link between common household spices and type 2 diabetes. Only common household spices were researched so that any link found between spices and type 2 diabetes could lead to practical home‐based recommendations for changes in a person's diet.
Findings
Cinnamon, garlic, ginger, basil, oregano, nutmeg, tea, bay leaf, allspice, curry, and others were found to play a role in lowering blood glucose, increasing insulin sensitivity, and increasing glucose synthesis in response to food intake. In addition, these spices may improve blood circulation, decrease platelet aggregation, lower blood pressure, and act as blood vessel protectants, ameliorating the cardiovascular disease often associated with type 2 diabetes. To gain these benefits, only average amounts commonly used in foods are necessary, such as amounts usually sprinkled in foods or amounts used in recipes. At high concentrated doses, the advantages to utilizing spices may be inhibited.
Originality/value
The findings that phytochemicals in common household spices can improve insulin activity in the body present a more natural way to possibly treat and prevent type 2 diabetes.
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Hui Li, Lei Xu and Youqing Fan
The purpose of this paper is to explore mechanisms of cultural distance in the base of Chinese Service Multi-National Enterprise (MNE) settings. When attempting to enter overseas…
Abstract
Purpose
The purpose of this paper is to explore mechanisms of cultural distance in the base of Chinese Service Multi-National Enterprise (MNE) settings. When attempting to enter overseas markets, many service MNEs face challenges caused by the cultural distance between the home and host countries. Culture distance attracts much attention in academia and industry. However, there are few empirical works to examine how cultural distance affects customer orientation strategies in a global supply chain. This paper aims to answer the following research question: How is the effect of cultural distance on customer acquisition and customer retention strategies, and the effect of customer orientation strategies on the performance of service-oriented MNEs controlled by Chinese capital along the Belt and Road Initiative?
Design/methodology/approach
This paper examines the effect of cultural distance on the customer acquisition strategy and customer retention strategy, and the effect of customer orientation strategies on the performance of Chinese Service MNEs. A large-scale empirical study of Chinese Service MNEs operating in overseas markets is performed and questionnaires were distributed and collected. This paper uses Hofstede's method (Hofstede, 2010), Schwartz's method (Schwartz, 2003) and House et al.'s method (House et al., 2004) to calculate cultural distance. By using each kind of method, this study calculates the absolute culture distance and relative culture distance respectively.
Findings
The results suggest that cultural distance negatively affects customer orientation strategy, customer acquisition strategy positively affects performance and the interaction of customer acquisition and customer retention positively affects performance.
Research limitations/implications
This study aims to contribute to the existing literature with a more fine-grained understanding of the inclusion of customer orientation strategy of Chinese Service MNEs in global supply chains.
Practical implications
The findings outline several important implications that Chinese Service MNEs seeking to expand to overseas markets.
Originality/value
This paper contributes a novel, combined perspective of culture distance and customer orientation strategy.
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Ida Papallo, Domenico Solari, Ilaria Onofrio, Lorenzo Ugga, Renato Cuocolo, Massimo Martorelli, Teresa Russo, Ilaria Bove, Luigi Maria Cavallo and Antonio Gloria
This study aims to integrate design methods and additive manufacturing with the use of a thermoplastic elastomer certified for medical use and reverse engineering towards a new…
Abstract
Purpose
This study aims to integrate design methods and additive manufacturing with the use of a thermoplastic elastomer certified for medical use and reverse engineering towards a new concept of a customized buttress model with optimized features for the reconstruction of the osteo-dural opening after endoscopic endonasal transtuberculum-transplanum approach.
Design/methodology/approach
Additive manufacturing allows making of cost-effective and useable devices with tailored properties for biomedical applications. The endoscopic endonasal approach to the suprasellar area enables the management of different intradural tumours, and the craniectomy at the skull base is generally wide and irregular. Defining an optimal strategy for osteodural defect closure at the preoperative stage represents a significant challenge.
Findings
Using the results obtained from a computed tomography analysis, skull base defects were designed to plan the surgical approach. Several concepts of customized buttress models were first built up, initially focusing on thin, flexible edges characterized by different thicknesses. Finite element analyses and design optimization allowed us to achieve the optimal design solution with improved compliance/flexibility for easy intranasal manoeuvrability, maintaining an adequate mechanical stability. As the thickness of the edges decreased, an increase of strain energy values was found (i.e. 1.2 mJ – Model A, 1.7 mJ – Model B, 2.3 mJ – Model C, 4.3 mJ – Model D). However, a further optimization (Model E) led to a significant increase of the compliance (strain energy of 14.1 mJ).
Originality/value
The results obtained from clinical evaluations demonstrated the feasibility of the proposed technical solutions, improving surgery effectiveness.
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Rishika Nayyar, Jaydeep Mukherjee and Sumati Varma
The purpose of the paper is to examine the role of institutional distance as a determinant of outward foreign direct investment (OFDI) from India. The study combines a nuanced…
Abstract
Purpose
The purpose of the paper is to examine the role of institutional distance as a determinant of outward foreign direct investment (OFDI) from India. The study combines a nuanced view of institutional distance, with traditional location factors to analyze Indian OFDI flows to developed and emerging economies (EEs) during the period 2009 to 2017.
Design/methodology/approach
The paper employs fixed effects panel regression model on an unbalanced panel data set.
Findings
The findings suggest that India's OFDI is undeterred by the isomorphic pressures caused by regulatory and normative institutional distance, but cognitive institutional distance acts as a deterrent in developed economies. Indian MNEs engage in institutional arbitrage as they simultaneously engage in strategies of institutional escapism and institutional exploitation. The study also finds that emerging economies have emerged as an important destination for strategic asset seeking FDI, in addition to developed economies.
Practical implications
The findings of the study present important implications for policymakers and corporate managers. For policymakers, the study points toward the need for improving the general business environment at home to prevent escapist OFDI and trade enhancement as a tool to overcome cognitive barriers and behavioristic stereotypes. For corporate managers, the study's findings underline the importance of adopting different strategies for dealing with different isomorphic pressures in developed and emerging economies.
Originality/value
The study adds value to the sparse literature using the IBV in the emerging markets context, to supplement and enrich existing theoretical frameworks. It is a pioneering study in its use of institutional distance as an explanatory factor for Indian OFDI and provides evidence of institutional arbitrage.
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Munwar Hussain Pahi, Waheed Ali Umrani, Abdul Waheed Siyal, Umair Ahmed and Said Al Riyami
The present study attempts to extend our understanding of the application of self-determination theory. The study examines the mediating role of self-efficacy and self-esteem in…
Abstract
Purpose
The present study attempts to extend our understanding of the application of self-determination theory. The study examines the mediating role of self-efficacy and self-esteem in the relationship between family motivation and academic performance.
Design/methodology/approach
Through adopting a survey questionnaire, we collected 329 responses from management educators (faculty members teaching in business schools) from various universities.
Findings
The data were analyzed using the partial least square structural equation modeling technique. All the hypothesized relationships found empirical support, indicating that family motivation is directly related to academic performance. Furthermore, self-efficacy and self-esteem mediate this direct relationship.
Originality/value
The paper forwards robust theoretical and practical implications and underlines important directions for future researchers. The study makes novel contributions to relationships inviting for empirical attention.
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Advanced big data analysis and machine learning methods are concurrently used to unleash the value of the data generated by government hotline and help devise intelligent…
Abstract
Purpose
Advanced big data analysis and machine learning methods are concurrently used to unleash the value of the data generated by government hotline and help devise intelligent applications including automated process management, standard construction and more accurate dispatched orders to build high-quality government service platforms as more widely data-driven methods are in the process.
Design/methodology/approach
In this study, based on the influence of the record specifications of texts related to work orders generated by the government hotline, machine learning tools are implemented and compared to optimize classify dispatching tasks by performing exploratory studies on the hotline work order text, including linguistics analysis of text feature processing, new word discovery, text clustering and text classification.
Findings
The complexity of the content of the work order is reduced by applying more standardized writing specifications based on combining text grammar numerical features. So, order dispatch success prediction accuracy rate reaches 89.6 per cent after running the LSTM model.
Originality/value
The proposed method can help improve the current dispatching processes run by the government hotline, better guide staff to standardize the writing format of work orders, improve the accuracy of order dispatching and provide innovative support to the current mechanism.