Search results

1 – 7 of 7
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 1 January 1992

J.F. BRUDNY, Ph. DELARUE and F. NOTELET

The torque harmonics generated by asynchronous machine slotting are essentially linked to air‐gap permeance variations due to the rotor rotation. These variations lead to machine…

43

Abstract

The torque harmonics generated by asynchronous machine slotting are essentially linked to air‐gap permeance variations due to the rotor rotation. These variations lead to machine inductance coefficient fluctuations which are at the begining of torque harmonics. So the problem consists to determine the permeance variation law as well as for its mean value that for its “harmonics”. The aim of this study is to end at analytical expressions which allow to calculate the torque harmonic magnitudes whatever the considered machine. In consequence the numerical methods (e.g. finite element method) are not appropriated because their implementation considering the rotation will be too long and, in the other hand, they only permit, from calculus results, to estimate this permeance variation law. To resolve this problem by analytical way this law must be characterized by a simple expression. That leads the authors to translate the complex phenomena, linked to the field line repartition in the slotting, by simple laws applied to a fictitious slot model. After presenting the selected model to characterize the slots, the authors introduce the angle per unit permeance notion which permits to make clear the air gap permeance variation law in function of rotor rotation. The experimental verifications which relate to inductance coefficients and torque harmonics permit to validate these permeance variation law and in consequence the selected fictitious slot model. The evolution of these quantities in function of the magnetic field magnitude inside the machine permits the authors to propose a fictitious slot model evolution law which can take the saturation into account.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 11 no. 1
Type: Research Article
ISSN: 0332-1649

Access Restricted. View access options
Article
Publication date: 1 April 1993

Emile‐Gaston Peeters

Reviews determining factors for cancer – both intrinsic(cellular oncogenes and growth factors) and extrinsic (viruses, soilcomposition, wastewater recycling, dietetic factors…

55

Abstract

Reviews determining factors for cancer – both intrinsic (cellular oncogenes and growth factors) and extrinsic (viruses, soil composition, wastewater recycling, dietetic factors and chemoprevention). Concludes that it should be possible progressively to eliminate the extrinsic factors from our ecosystems. Discusses geographic variations in cancer frequency, incidence among migrant populations, victims′ habits and occupational cancers.

Details

Environmental Management and Health, vol. 4 no. 4
Type: Research Article
ISSN: 0956-6163

Keywords

Access Restricted. View access options
Article
Publication date: 10 May 2022

Yi Jing Thun, See Wan Yan, Chin Ping Tan, Wen Xin Teoh and Xin Yue Gan

Prevention of chronic diseases by means of dietary modification can be achieved by consuming healthier foods with lower sugar content. However, reducing sugar content causes…

303

Abstract

Purpose

Prevention of chronic diseases by means of dietary modification can be achieved by consuming healthier foods with lower sugar content. However, reducing sugar content causes significant impact on the sensory quality and consumers’ acceptance towards local healthy products. This study aims to evaluate the effects of cross-modal interactions of Aroma-Taste-Texture (ATT) in yoghurt drink.

Design/methodology/approach

Fifteen sugar reduced yoghurt drinks [S, sugar percentage (0%, 2%, 4%); T, stevia dosage (0%, 0.01%, 0.02%); P, pectin dosage (0%, 0.3%, 0.6%)] based on ATT were evaluated by 300 consumer panellists on aroma, taste, texture and overall acceptability on a nine-point hedonic scale while sweetness intensity was measured using a seven-point just-about-right (JAR) scale. Interactions between ATT were determined.

Findings

Significant interaction was found between sugar and stevia, with F14 (4S0.02T0P) rated as sweeter than F4 (0S0.02T0P) (p = 0.003) and higher overall liking score than F11 (4S0T0P) (p = 0.001). Similarly, significant interaction was found between sugar and pectin, with F2 (0S0T0.6P) rated as significantly lower overall liking score and less sweet than F1 (0S0T0P) (p = 0.0001). Likewise, significant interaction was found between stevia and pectin, with F2 (0S0T0.6P) rated as significantly lower overall liking score and less sweet than F1 (0S0T0P) (p = 0.0001). Overall, F5 (0S0.02T0.6P) scored highest in overall liking and closest to the ideal sweetness (JAR = 4) indicating the possibility to apply 100% sugar replacement.

Originality/value

Application from the present study could be great potential solution in developing healthier range products while meeting consumer preference. The present study concluded that interactions of ATT of yoghurt drink will induce desirable changes in sensory and sweetness perception.

Details

Nutrition & Food Science , vol. 53 no. 1
Type: Research Article
ISSN: 0034-6659

Keywords

Access Restricted. View access options
Article
Publication date: 4 April 2016

Åsa Grytli Tveten and Torjus Folsland Bolkesjø

The purpose of this study is to analyze the power market and greenhouse gas (GHG) emission effects of the joint Norwegian–Swedish tradable green certificates (TGCs) market, which…

608

Abstract

Purpose

The purpose of this study is to analyze the power market and greenhouse gas (GHG) emission effects of the joint Norwegian–Swedish tradable green certificates (TGCs) market, which is established to support investments according to a 26.4 TWh increased annual renewable electricity generation (REG) by 2020.

Design/methodology/approach

The study applies an energy system model with high granularity in time and space, and detailed power system data for the Nordic countries, Germany, The Netherlands and UK.

Findings

The results show that the TGC scheme will cause a 8.7-9.3 /MWh reduction in average electricity prices in the Nordic countries. The price decrease will to a limited extent pass through to Germany, The Netherlands and UK. When assuming a low carbon price level, the new REG will reduce annual GHG emissions by 10.9 Mtonnes in 2020, primarily through substitution of German natural gas power. A sensitivity analysis shows that the GHG emission effect of the TGCs is highly sensitive to changes in the carbon price. Investment levels up to a 90 TWh increased REG per year are found to cause increasing GHG emission reductions.

Originality/value

The study results signal the importance of taking the TGC policy into account in decision-making processes in the Northern European power system, in particular for market actors in the Nordic area. The authors conclude that the Nordic countries potentially can play a vital role in a future Northern European low carbon power system through export of green balancing power, substitution of thermal power and reduced GHG emissions from the Northern European power sector.

Details

International Journal of Energy Sector Management, vol. 10 no. 1
Type: Research Article
ISSN: 1750-6220

Keywords

Available. Open Access. Open Access
Article
Publication date: 30 October 2020

Juliana Chini, Eduardo Eugênio Spers, Hermes Moretti Ribeiro da Silva and Mirella Cais Jejcic de Oliveira

This study aims to identify the marginal impact of introducing a signal attribute of pasture-raised beef on consumer willingness to pay (WTP) for other independent attributes.

2991

Abstract

Purpose

This study aims to identify the marginal impact of introducing a signal attribute of pasture-raised beef on consumer willingness to pay (WTP) for other independent attributes.

Design/methodology/approach

The study is divided into two steps. The first, qualitative, consisted of investigating the values consumers have regarding beef production. To this end, 52 interviews with Brazilian and US consumers were conducted using laddering. In the second, quantitative, six experiments, (face to face and online) with 267 consumers of beef were performed.

Findings

As a result, the main value found for the Brazilians was security, while for the Americans was self-direction. For consumers, the WTP for animal welfare was the most important in the choice experiments where this information was present.

Originality/value

These findings offer an alternate beef differentiation, enabling it to be sold with higher added value by integrating these.

Details

RAUSP Management Journal, vol. 55 no. 4
Type: Research Article
ISSN: 2531-0488

Keywords

Access Restricted. View access options
Article
Publication date: 7 April 2023

Pedro Bento, Sílvio Mariano, Pedro Carvalho, Maria do Rosário Calado and José Pombo

This study is a targeted review of some of the major changes in European regulation that guided energy policy decisions in the Iberian Peninsula and how they may have aggravated…

105

Abstract

Purpose

This study is a targeted review of some of the major changes in European regulation that guided energy policy decisions in the Iberian Peninsula and how they may have aggravated the problem of lack of flexibility. This study aims to assess some of the proposed short-term solutions to address this issue considering the underlying root causes and suggests a different course of action, that in turn, could help alleviate future market strains.

Design/methodology/approach

The evolution of the most important (macro) energy and price-related variables in both Portugal and Spain is assessed using market and grid operator data. In addition, the authors present critical viewpoints on some of the most recent EU and national regulation changes (official document analysis).

Findings

The Iberian energy policy and regulatory agenda has successfully promoted a rapid adoption of renewables (main goal), although with insufficient diversification of generation technologies. The compulsory closings of thermal plants and an increased tax (mainly carbon) added pressure toward more environmentally friendly thermal power plants. However, inevitably, this curbed the bidding price competitiveness of these producers in an already challenging market framework. Moving forward, decisions must be based on “a bigger picture” that does not neglect system flexibility and security of supply and understands the specificities of the Iberian market and its generation portfolio.

Originality/value

This work provides an original account of unprecedented spikes in energy prices in 2021, specifically in the Iberian electricity market. This acute situation worries consumers, industry and governments. Underlining the instability of the market prices, for the first time, this study discusses how some of the most important regulatory changes, and their perception and absorption by involved parties, contributed to the current environment. In addition, this study stresses that if flexibility is overlooked, the overall purpose of having an affordable and reliable system is at risk.

Details

International Journal of Energy Sector Management, vol. 18 no. 2
Type: Research Article
ISSN: 1750-6220

Keywords

Access Restricted. View access options
Article
Publication date: 21 March 2016

Samaneh Matindoust, Majid Baghaei-Nejad, Mohammad Hadi Shahrokh Abadi, Zhuo Zou and Li-Rong Zheng

This paper aims to study different possibilities for implementing easy-to-use and cost-effective micro-systems to detect and trace expelled gases from rotten food. The paper…

7174

Abstract

Purpose

This paper aims to study different possibilities for implementing easy-to-use and cost-effective micro-systems to detect and trace expelled gases from rotten food. The paper covers various radio-frequency identification (RFID) technologies and gas sensors as the two promoting feasibilities for the tracing of packaged food. Monitoring and maintaining quality and safety of food in transport and storage from producer to consumer are the most important concerns in food industry. Many toxin gases, even in parts per billion ranges, are produced from corrupted and rotten food and can endanger the consumers’ health. To overcome the issues, intelligent traceability of food products, specifically the packaged ones, in terms of temperature, humidity, atmospheric conditions, etc., has been paid attention to by many researchers.

Design/methodology/approach

Food poisoning is a serious problem that affects thousands of people every year. Poisoning food must be recognized early to prevent a serious health problem.

Contaminated food is usually detectable by odor. A small gas sensors and low-cost tailored to the type of food packaging and a communication device for transmitting alarm output to the consumer are key factors in achieving intelligent packaging.

Findings

Conducting polymer composite, intrinsically conducting polymer and metal oxide conductivity gas sensors, metal–oxide–semiconductor field-effect transistor (MOSFET) gas sensors offer excellent discrimination and lead the way for a new generation of “smart sensors” which will mould the future commercial markets for gas sensors.

Originality/value

Small size, low power consumption, short response time, wide operating temperature, high efficiency and small area are most important features of introduced system for using in package food.

Details

Sensor Review, vol. 36 no. 2
Type: Research Article
ISSN: 0260-2288

Keywords

1 – 7 of 7
Per page
102050