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Article
Publication date: 26 July 2012

Weihong Fan, Raymond G. Mueller, Weili Qiu and Michael J. Hozik

– The purpose of this study is to compare the different pesticides management practices and productions in three apple farms in the Northeastern US and Northern China.

Abstract

Purpose

The purpose of this study is to compare the different pesticides management practices and productions in three apple farms in the Northeastern US and Northern China.

Design/methodology/approach

Interviews and surveys were conducted in the three farms between the summer of 2010 and spring of 2011. Production, pesticide and fertilizer usage, and labor costs were calculated for comparison.

Findings

The conventional US apple grower manages his farm for maximum production and minimum labor costs. As a result, the farm achieved a high yield of 24.68 kg/dollar, but low health value for the highest amount of pesticide expenditure ($2.43 per 100 kg of apples). The organic apple farm aims at minimizing environmental impact and protecting consumers. Its yield was 14.22 kg/dollar with 15-30 percent greater labor costs. The health value of the apples improved with pesticide expenditure of $1.66 per 100 kg of apples. This farm uses only the least toxic pesticide certified by OMRI. The traditional apple farm in Northern China spent 1,365 hours/ha on bagging to protect consumers, comparing to only 252 hours/ha of total labor spent in the conventional apple farm. Annual production of the Chinese farm was 22,727 kg/ha, which was only 50 percent of the conventional apple production and 71 percent of the organic apple production.

Originality/value

The results reveal great potential for a much better economic and environmental effectiveness in the Chinese apple farm if they redirect labor from bagging to an effort for production and efficient management while still providing consumer protection.

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Article
Publication date: 7 November 2016

Hongbo Qiu, Wenfei Yu, Bingxia Tang, Weili Li, Cunxiang Yang and Yanfeng Wang

Taking a 2,000 r/min 10 kW permanent magnet motor as an example, the purpose of this paper is to study the influence of driving modes on the performance of permanent…

Abstract

Purpose

Taking a 2,000 r/min 10 kW permanent magnet motor as an example, the purpose of this paper is to study the influence of driving modes on the performance of permanent magnet motor at limit conditions, and researched the variation mechanism of motor performance influenced by different driving modes.

Design/methodology/approach

A two-dimensional electromagnetic field model of the permanent magnet motor was established, and a rectangular-wave driving circuit was built. By using the finite element method, the electromagnetic field, current, harmonic content and eddy current loss were calculated when the motor operated at rated load and limit load. On the basis of the motor loss calculation, the temperature field of the motor operating at rated condition and limit condition was researched, and the factors that influence motor limit overload capacity were analyzed. By analyzing the motor loss variation at different load conditions, the change mechanism of the motor temperature field was determined further. Combined with the related experiments, the correctness of the above analysis was verified.

Findings

Permanent magnet synchronous motor (PMSM) driven by sine wave is better compared with brushless direct current motor (BLDCM) driven by rectangular wave in reducing the magnetic field harmonics, motor losses and optimizing the temperature distribution in the motor. The method driven by sine wave could improve the motor output performance including the motor efficiency and the motor overload capacity. The winding temperature is the most important factor that limits the output capability of PMSM operating for a long time. However, because of the large rotor eddy current losses, the permanent magnet temperature is the most important factor that limits the output capability of BLDCM operating for a long time.

Practical implications

The influence of driving modes on the motor magnetic field, losses and temperature distribution, efficiency and overload capacity was determined, and the influence mechanism was also analyzed. Combined with the analysis of the electromagnetic and temperature fields, the advantages of different driving modes were presented. This study could provide an important basis for the design of permanent magnet motors with different driving modes, and it also provides reference for the application of permanent magnet motor.

Originality/value

This paper presents the influence of driving modes on permanent magnet motors. The limit output capacity of the motor with different driving modes was studied, and the key factors limiting the motor output capability were obtained.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 35 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

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Article
Publication date: 3 July 2017

Hongbo Qiu, Wenfei Yu, Shuai Yuan, Bingxia Tang and Cunxiang Yang

The impact of the loop current (LC) on the motor magnetic field in the analysis of the inter-turn short circuit (ITSC) fault is always ignored. This paper made a…

Abstract

Purpose

The impact of the loop current (LC) on the motor magnetic field in the analysis of the inter-turn short circuit (ITSC) fault is always ignored. This paper made a comparative study on the electromagnetic field of permanent magnet synchronous motors (PMSM). The purpose of this study is to explore the necessary of the LC existing in the fault analysis and the electromagnetic characteristics of the PMSM with the ITSC fault when taking into account the LC.

Design/methodology/approach

Based on the finite element method (FEM), the fault model was established, and the magnetic density of the fault condition was analyzed. The induced electromotive force (EMF) and the LC of the short circuit ring were studied. The three-phase induced EMF and the unbalance of the three-phase current under the fault condition were studied. Finally, a prototype test platform was built to obtain the data of the fault.

Findings

The influence of the fault on the magnetic density was obtained. The current phase lag when the ITSC fault occurs causes the magnetic enhancement of the armature reaction. The mechanism that LC hinders the flux change was revealed. The influence of the fault on the three-phase-induced EMF symmetry, the three-phase current balance and the loss was obtained.

Originality/value

The value of the LC in the short circuit ring and the influence of it on the motor electromagnetic field were obtained. On the basis of the electromagnetic field calculation model, the sensitivity of the LC to the magnetic density, induced EMF, current and loss were analyzed.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

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Article
Publication date: 12 February 2018

Abdulmannan Fadel, Andrew Plunkett, Weili Li, Yazan Ranneh, Vivian Elewosi Tessu Gyamfi, Yasser Salmon, Rosemarie Roma Nyaranga and Jason Ashworth

The purpose of this study is to discuss recent research on arabinoxylans from rice bran and wheat byproducts and their immunomodulatory potentials. Also, a potential…

Abstract

Purpose

The purpose of this study is to discuss recent research on arabinoxylans from rice bran and wheat byproducts and their immunomodulatory potentials. Also, a potential receptor for arabinoxylans is proposed in relation to arabinoxylans structure.

Design/methodology/approach

This review summarises recent publications on arabinoxylans from rice bran and wheat, classification of arabinoxylans, a brief background on their method of extraction and their immunomodulatory potentials as they induce pro-inflammatory response in vitro, in vivo and in humans. The mechanism of action in which arabinoxylans modulate the immune activity is yet to be discovered, However, the authors have proposed a potential receptor for arabinoxylans in relation to arabinoxylans structure and molecular weight.

Findings

The effects of arabinoxylans from rice bran and wheat on the immune response was found to cause a pro-inflammatory response in vitro, in vivo and in humans. Also, the immune response depends on arabinoxylans structure, the degree of branching and origin.

Originality/value

This review paper focuses on the effects of arabinoxylans from rice bran and wheat on immunomodulatory potentials in vitro, in vivo and in humans. A new mechanism of action has been proposed based on the literature and via linking between arabinoxylans and lipopolysaccharide structure, molecular weight and suggested proposed receptor, which might be activated via both of them.

Details

Nutrition & Food Science, vol. 48 no. 1
Type: Research Article
ISSN: 0034-6659

Keywords

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Book part
Publication date: 9 October 2020

Ali C. Akyol

Abstract

Details

Corporate Fraud Exposed
Type: Book
ISBN: 978-1-78973-418-8

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Article
Publication date: 9 May 2020

João L.F.R. Fragoso, Rúben M.T. Peixinho, Luís M.S. Coelho and Inna C.S. Paiva

The purpose of this paper is to discuss the most relevant issues related to the impact of financial restatements in the dynamics of financial markets and identify several…

Abstract

Purpose

The purpose of this paper is to discuss the most relevant issues related to the impact of financial restatements in the dynamics of financial markets and identify several research gaps to be investigated in future research.

Design/methodology/approach

The methodology is based on a systematic review of the literature described by Tranfield et al. (2003). The final sample includes 47 academic papers published from 1996 to 2019.

Findings

Papers in this domain discuss three main topics: how the market prices the announcement of a financial restatement; how financial restatements affect the announcing firm’s cost of capital and how financial restatements affect firms’ reputation. There are several issues to explore in future research, including whether financial restatements affect the dynamics of financial markets in Europe, whether the market fully and promptly assimilates the information content of a restatement, the role of financial analysts’ information disclosures in this process or how regulators may improve the way they provide investors with timely information about firms’ restating problems.

Research limitations/implications

There is always some degree of subjectivity in the definition of the keywords, search strings and selection criteria in a systematic review. These are all important aspects, as they delimitate the scope of the study and define the sample of papers to be reviewed.

Practical implications

The answers to the research questions identified in this paper may provide regulators with information to improve financial accounting and reporting standards and strengthen investors’ confidence in accounting information and the dynamics of financial markets.

Originality/value

This paper systematically reviews the relevant literature exploring the connection between financial restatements and the dynamics of financial markets. It contributes to the academic community by identifying several research questions that may impact the theory and practice related to accounting quality and capital markets.

Details

Meditari Accountancy Research, vol. 28 no. 6
Type: Research Article
ISSN: 2049-372X

Keywords

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