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Article
Publication date: 30 January 2007

This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/17488840610639681. When citing the…

290

Abstract

This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/17488840610639681. When citing the article, please cite: Xiujie Jiang, Huixian Sun, Xiaomin Chen, Zhihua Wang, Li Zhang, Daxing Wang, (2006), “Utilization of a COTS component in temperature measurement system for microgravity fluid experiment on SZ-4 spaceship”, Aircraft Engineering and Aerospace Technology, Vol. 78 Iss: 1, pp. 45 - 49.

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 1
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 January 2006

Xiujie Jiang, Huixian Sun, Xiaomin Chen, Zhihua Wang, Li Zhang and Daxing Wang

This paper presents a new multi‐channel temperature measurement system (MCTMS) with small size, light weight and low power consumption for the microgravity fluid experiment of…

Abstract

Purpose

This paper presents a new multi‐channel temperature measurement system (MCTMS) with small size, light weight and low power consumption for the microgravity fluid experiment of drop Marangoni migration on SZ‐4 spaceship, a test module of the manned space mission of China.

Design/methodology/approach

The MCTMS, with a commercial‐off‐the‐shelf (COTS) component monolithic thermocouple amplifier with cold junction compensation AD595, is designed to measure temperature gradient field of up to 6 type T thermocouples Cu‐Constantan for microgravity fluid experiment. Through an analog multiplexer, the very small signal amplitude of the six‐channel temperatures can be acquired and amplified by the same monolithic thermocouple amplifier to retain the consistency of the six channels. A fully mission analysis and evaluation on the COTS component was taken into account before it was used in the thermal and radiation environment of space.

Findings

Using the COTS component in space can increase the system performance and considerably reduce the size, weight, power consumption and the overall complexity of the system. The measurement resolution of the MCTMS reaches 0.1°C because of the utilization of the COTS with high performance. In addition, the transfer function of the AD595 was deduced for type T thermocouples.

Originality/value

This paper suggests an easy way of measuring temperature for microgravity fluid experiment on spacecraft. Using a COTS component on spacecraft, also, is a new practical case study, which is more suitable for on‐board implementation. The MCTMS, presented in this work, has run in‐orbit successfully on SZ‐4 spaceship and the experiment result in space is reported.

Details

Aircraft Engineering and Aerospace Technology, vol. 78 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 14 March 2023

Florin Aliu, Isa Mulaj and Simona Hašková

The Russian invasion of Ukraine generated unprecedented panic in the European financial system. As expected, the European Union (EU) felt most of the negative effects of the war…

Abstract

Purpose

The Russian invasion of Ukraine generated unprecedented panic in the European financial system. As expected, the European Union (EU) felt most of the negative effects of the war due to geographical proximity to Ukraine and energy dependence on Russia. This study aims to investigate the influence of Brent crude oil (BCO), Dutch Title Transfer Facility Natural Gas, and CBOE Volatility Index (VIX) on Deutscher Aktien Index (DAX), Austrian Traded Index (ATX) and Milano Indice di Borsa (FTSEMIB). The German, Austrian and Italian equity indexes were chosen due to the heavy dependence of these countries on Russian gas and oil.

Design/methodology/approach

The data cover the period from November 24, 2021, to June 24, 2022, including five months of the Russia–Ukraine war. To generate the intended results, vector autoregressive, structural vector autoregressive, vector error correction model, Johansen test and Granger causality test were used.

Findings

The results highlight that natural gas and the VIX carried negative effects on DAX, ATX and FTSEMIB. The BCO was expected to have influenced three selected equity indexes, while the results suggest that it was priced only in ATX.

Originality/value

This research provides modest evidence for the policymakers on the systemic risk that Russian gas has for the EU equity markets. From a managerial perspective, changes in oil and gas prices are a permanently integral part of portfolio risk analysis.

Details

Studies in Economics and Finance, vol. 40 no. 3
Type: Research Article
ISSN: 1086-7376

Keywords

Article
Publication date: 19 July 2021

Taicir Mezghani, Fatma Ben Hamadou and Mouna Boujelbène Abbes

The aim of this study was to investigate the dynamic network connectedness between stock markets and commodity futures and its implications on hedging strategies. Specifically…

Abstract

Purpose

The aim of this study was to investigate the dynamic network connectedness between stock markets and commodity futures and its implications on hedging strategies. Specifically, the authors studied the impact of the 2014 oil price drop and coronavirus disease 2019 (COVID-19) pandemic on risk spillovers and portfolio allocation among stock markets (United States (SP500), China (SSEC), Japan (Nikkei 225), France (CAC40) and Germany (DAX)) and commodities (oil and gold).

Design/methodology/approach

In this study, the authors used the Baba, Engle, Kraft and Kroner–generalized autoregressive conditional heteroskedasticity (BEKK–GARCH) model to estimate shock transmission among the five financial markets and the two commodities. The authors rely on Diebold and Yılmaz (2014, 2015) methodology to construct network-associated measures.

Findings

Relying on the BEKK–GARCH, the authors found that the recent health crisis of COVID-19 intensified the volatility spillovers among stock markets and commodities. Using the dynamic network connectedness, the authors showed that at the 2014 oil price drop and the COVID-19 pandemic shock, the Nikkei225 moderated the transmission of volatility to the majority of markets. During the COVID-19 pandemic, the commodity markets are a net receiver of volatility shocks from stock markets. In addition, the SP500 stock market dominates the network connectedness dynamic during the COVID-19 pandemic, while DAX index is the weakest risk transmitter. Regarding the portfolio allocation and hedging strategies, the study showed that the oil market is the most vulnerable and risky as it was heavily affected by the two crises. The results show that gold is a hedging tool during turmoil periods.

Originality/value

This study contributes to knowledge in this area by improving our understanding of the influence of fluctuations in oil prices on the dynamics of the volatility connection between stock markets and commodities during the COVID-19 pandemic shock. The study’s findings provide more implications regarding portfolio management and hedging strategies that could help investors optimize their portfolios.

Details

Asia-Pacific Journal of Business Administration, vol. 13 no. 4
Type: Research Article
ISSN: 1757-4323

Keywords

Article
Publication date: 12 January 2023

Shaoyi Liu, Songjie Yao, Song Xue, Benben Wang, Hui Jin, Chenghui Pan, Yinwei Zhang, Yijiang Zhou, Rui Zeng, Lihao Ping, Zhixian Min, Daxing Zhang and Congsi Wang

Surface mount technology (SMT) is widely used and plays an important role in electronic equipment. The purpose of this paper is to reveal the effects of interface cracks on the…

Abstract

Purpose

Surface mount technology (SMT) is widely used and plays an important role in electronic equipment. The purpose of this paper is to reveal the effects of interface cracks on the fatigue life of SMT solder joint under service load and to provide some valuable reference information for improving service reliability of SMT packages.

Design/methodology/approach

A 3D geometric model of SMT package is established. The mechanical properties of SMT solder joint under thermal cycling load and random vibration load were solved by 3D finite element analysis. The fatigue life of SMT solder joint under different loads can be calculated by using the modified Coffin–Manson model and high-cycle fatigue model.

Findings

The results revealed that cracks at different locations and propagation directions have different effect on the fatigue life of the SMT solder joint. From the location of the cracks, Crack 1 has the most significant impact on the thermal fatigue life of the solder joint. Under the same thermal cycling conditions, its life has decreased by 46.98%, followed by Crack 2, Crack 4 and Crack 3. On the other hand, under the same random vibration load, Crack 4 has the most significant impact on the solder joint fatigue life, reducing its life by 81.39%, followed by Crack 1, Crack 3 and Crack 2. From the crack propagation direction, with the increase of crack depth, the thermal fatigue life of the SMT solder joint decreases sharply at first and then continues to decline almost linearly. The random vibration fatigue life of the solder joint decreases continuously with the increase of crack depth. From the crack depth of 0.01 mm to 0.05 mm, the random vibration fatigue life decreases by 86.75%. When the crack width increases, the thermal and random vibration fatigue life of the solder joint decreases almost linearly.

Originality/value

This paper investigates the effects of interface cracks on the fatigue life and provides useful information on the reliability of SMT packages.

Details

Microelectronics International, vol. 40 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Book part
Publication date: 12 March 2020

Giorgio Mion and Cristian R. Loza Adaui

Public-interest entities – among which are listed companies – are obliged to publish nonfinancial disclosure in some countries and regions. The European Commission established…

Abstract

Public-interest entities – among which are listed companies – are obliged to publish nonfinancial disclosure in some countries and regions. The European Commission established mandatory nonfinancial disclosure by Directive 2014/95/EU. While a large body of literature was developed on sustainability reporting quality (SRQ) in voluntary context, evidence about the effect of mandatory nonfinancial disclosure on SRQ is controversial and previous experiences worldwide did not make clear if obligatoriness improves SRQ. This chapter aims to bridge the gap of empirical evidence about this phenomenon in European countries, focusing on first implementation of new legislation by Italian and German companies. The research has an explorative character and it adopts content analysis methods performed on sustainability reporting practices of companies listed in FTSE-MIB and DAX 30. The analysis aims to understand if obligatoriness affects SRQ, causes some changes in reporting practices such as harmonizing Italian and German ones by performing a cross-country comparison. The findings suggest that obligatoriness improves reporting quality and, above all, it fills the gap between different countries by fostering the adoption of international guidelines and the consequent introduction of some content, such as materiality analysis and quantitative measures of social and environmental performance.

Details

Non-Financial Disclosure and Integrated Reporting: Practices and Critical Issues
Type: Book
ISBN: 978-1-83867-964-4

Keywords

Article
Publication date: 8 August 2022

Mohammad Shahid, Zubair Ashraf, Mohd Shamim and Mohd Shamim Ansari

Optimum utilization of investments has always been considered one of the most crucial aspects of capital markets. Investment into various securities is the subject of portfolio…

Abstract

Purpose

Optimum utilization of investments has always been considered one of the most crucial aspects of capital markets. Investment into various securities is the subject of portfolio optimization intent to maximize return at minimum risk. In this series, a population-based evolutionary approach, stochastic fractal search (SFS), is derived from the natural growth phenomenon. This study aims to develop portfolio selection model using SFS approach to construct an efficient portfolio by optimizing the Sharpe ratio with risk budgeting constraints.

Design/methodology/approach

This paper proposes a constrained portfolio optimization model using the SFS approach with risk-budgeting constraints. SFS is an evolutionary method inspired by the natural growth process which has been modeled using the fractal theory. Experimental analysis has been conducted to determine the effectiveness of the proposed model by making comparisons with state-of-the-art from domain such as genetic algorithm, particle swarm optimization, simulated annealing and differential evolution. The real datasets of the Indian stock exchanges and datasets of global stock exchanges such as Nikkei 225, DAX 100, FTSE 100, Hang Seng31 and S&P 100 have been taken in the study.

Findings

The study confirms the better performance of the SFS model among its peers. Also, statistical analysis has been done using SPSS 20 to confirm the hypothesis developed in the experimental analysis.

Originality/value

In the recent past, researchers have already proposed a significant number of models to solve portfolio selection problems using the meta-heuristic approach. However, this is the first attempt to apply the SFS optimization approach to the problem.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 16 no. 2
Type: Research Article
ISSN: 1756-378X

Keywords

Article
Publication date: 11 May 2010

Qiao Zhang and Ke Wang

The purpose of this paper is to assess the production risk for winter wheat producers in Beijing, China, particularly in its 13 districts.

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Abstract

Purpose

The purpose of this paper is to assess the production risk for winter wheat producers in Beijing, China, particularly in its 13 districts.

Design/methodology/approach

A parametric approach is used to model wheat‐yield distribution for samples and the Kolmogorov‐Smirnov test is used to choose the most appropriate yield distribution. Parameters of the special yield distribution are estimated through the maximum likelihood estimation approach.

Findings

The Burr distribution is found to be the most appropriate parametric distribution to model winter wheat‐production risks for the districts of Beijing, except in the districts of Fengtai and Shunyi. Findings also show that the Johnson family distribution is the most appropriate model for these two districts (SB for the Fengtai District and SU for the Shunyi District). The wheat‐production loss ratios of the Beijing districts are between 6 and 15 percent, which is considered medium range in most regions. The highest production risks are located in the Western regions of Beijing (Mentougou and Fengtai) while the lowest production risk is located in the Southeastern region of Beijing (Daxing District).

Originality/value

To generate an objective yield trend and an accurate production risk assessment, linear moving average, instead of linear (or quadratic) regression, is used in this paper.

Details

China Agricultural Economic Review, vol. 2 no. 2
Type: Research Article
ISSN: 1756-137X

Keywords

Article
Publication date: 20 July 2012

David B. Heinz and Matthias Tomenendal

There is a stream of literature highlighting the enormous growth potential of emerging markets. This literature forms the basis for strategic investment decisions made by…

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Abstract

Purpose

There is a stream of literature highlighting the enormous growth potential of emerging markets. This literature forms the basis for strategic investment decisions made by multinational corporations (MNCs). Seeking to question the findings of this literature, this paper aims to undertake a comparison of the BRIC countries with that of Germany as a representative mature market to put into perspective the short to medium‐term market potential of BRIC markets.

Design/methodology/approach

An analysis of the geographical investment priorities of 25 DAX multinationals operating in the real economy and a statistical comparison of market size and growth between BRIC countries and Germany are undertaken.

Findings

While the majority of the DAX companies examined focused their strategic investment priorities on emerging markets, the short‐ to mid‐term revenue potential of the BRIC countries – currently the most important emerging markets – are expected to be lower in absolute terms than those for mature markets such as Germany. This holds true on several levels of granularity, such as GPD per capita, size and growth of high‐income market segments.

Research limitations/implications

The considerable “hype” surrounding focusing investment on emerging markets needs closer scrutiny. Further research is required to subject the reasons behind the strategic investments of MNCs in BRIC countries to more detailed analysis. This encompasses, for example, a closer consideration of the extent to which messages from the company reports might not reflect true strategic priorities but rather represent a means of public relations or tactical ploys. Next, the impact of real long‐term expectations and potential bandwagon effects require further study. Finally, a comprehensive theoretical model placing emerging market growth into a broader perspective has yet to be developed.

Practical implications

Decision makers in business, government and NGOs should not be misled by the “hype” surrounding emerging markets. In many industries, BRIC countries do and will provide smaller markets when compared to mature markets like Germany.

Originality/value

Direct comparison of market growth in the BRIC countries and that in Germany reveals greater short‐ to medium‐term absolute growth potential in Germany, a fact often ignored by current literature on international growth strategies and not reflected in the growth priorities published by German DAX companies.

Details

Critical perspectives on international business, vol. 8 no. 3
Type: Research Article
ISSN: 1742-2043

Keywords

Article
Publication date: 14 June 2022

Jingqi Zhang, Hui Zhao, Zhijie Li and Ziliang Guo

The purpose of this paper is to evaluate green buildings from the angle of greenness and improve the evaluation system. And the matter-element extension method is used to evaluate…

Abstract

Purpose

The purpose of this paper is to evaluate green buildings from the angle of greenness and improve the evaluation system. And the matter-element extension method is used to evaluate the greenness of green buildings, in order to provide useful references for the evaluation system of green buildings.

Design/methodology/approach

First, this paper studies the aspects of safety and durability, health and comfort, living convenience, resource-saving, environmental liability and ecological quality, etc. For the first time, carbon emission is included in the evaluation system, 18 key evaluation indexes are determined by using the Delphi method, and the green building evaluation index system is established. Then, the combined weight method is proposed to determine the weight of each evaluation index, and the greenness evaluation model of green building is established with the matter-element extension method. Finally, taking Beijing Daxing International Airport as an example, the evaluation model of green building greenness was established to evaluate the building.

Findings

In this paper, the greenness evaluation model of green building established by the matter-element extension method solves the problem of incompatibility between qualitative and quantitative material elements in multi-factor evaluation. It makes the evaluation indexes more accurate and objective relative to the affiliation calculation of the evaluation set and improves the scientific, accuracy and reliability of the evaluation model.

Originality/value

In this paper, for the first time, carbon emission-related indicators are included in the green building evaluation system, which makes the evaluation system more perfect. In addition, a more scientific extension matter-element method is used to evaluate the greenness of green buildings, breaking the previous rough star evaluation method.

Details

Kybernetes, vol. 52 no. 10
Type: Research Article
ISSN: 0368-492X

Keywords

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