Search results

Smart contracts are written in high-level programming languages, compiled into Ethereum Virtual Machine (EVM) bytecode, deployed onto blockchain systems and called with the corresponding address by transactions. The deployed smart contracts are immutable, even if there are bugs or vulnerabilities. Therefore, it is critical to verify smart contracts before deployment. This paper aims to help developers effectively and efficiently locate potential defects in smart contracts.

GethReplayer, a smart contract testing method based on transaction replay, is proposed. It constructs a parallel transaction execution environment with two virtual machines to compare the execution results. It uses the real existing transaction data on Ethereum and the source code of the tested smart contacts as inputs, conditionally substitutes the bytecode of the tested smart contract input into the testing EVM, and then monitors the environmental information to check the correctness of the contract.

Experiments verified that the proposed method is effective in smart contract testing. Virtual environmental information has a significant effect on the success of transaction replay, which is the basis for the performance of the method. The efficiency of error locating was approximately 14 times faster with the proposed method than without. In addition, the proposed method supports gas consumption analysis.

This paper addresses the difficulty that developers encounter in testing smart contracts before deployment and focuses on helping develop smart contracts with as few defects as possible. GethReplayer is expected to be an alternative solution for smart contract testing and provide inspiration for further research.

This chapter explores blockchain's five key elements ‒ distribution, encryption, immutability, tokenization, and decentralization. It also examines blockchain's potential to revolutionize today's businesses by looking at the efficiency and transparency blockchain brings to business processes. In addition, the chapter discusses the added benefits of traceability and potentially decreasing long-term costs before reviewing some of the known technical challenges blockchain faces today especially pertaining to commercial and enterprise adoption. Limited block size and low-transaction rates potentially inhibit blockchain's ability to scale to meet the needs of current and future enterprises. The lack of blockchain standards, along with creating multiple blockchains, complicates interoperability between the various blockchain platforms. The chapter concludes by offering potential solutions to blockchain's current technical challenges and how enterprises might adapt blockchain in the future.

The purpose of this paper is to examine the role and importance of trust in a type of Chinese farmer cooperative organization called “Farm Bases” (FBs), considering the extent to which trust affects their performance and how the relationship between trust and FB performance is affected by perceptions of risk and uncertainty and other considerations.

The authors interviewed a random sample of 355 farmers, most of whom are from 42 different FBs in China. The authors operationalized organizational trust by assessing the perception of trustworthiness and competence that farmers have in FB managers. The authors conducted a regression analysis of the data to answer the research questions.

The findings support a nuanced role of trust for performance measures of FBs. Trust matters but in limited and specific contexts. Specifically, trust does not correlate with the marketing volume of Chinese FBs and only weakly correlates with FB compliance of production standards.

FBs play an essential role in China’s agribusiness policies and are pervasive in Chinese business practices. Very little research has been conducted on Chinese FBs and of the role of trust in organizational performance.

This paper aims to explore the relationship between prudence in risk attitudes and patience of time preference of Chinese apple growers regarding off-farm cold storage of production and marketing in non-harvest seasons. The authors also consider the effect of farmer participation in cooperative-like organizations known as Farm Bases (FBs).

The authors use multiple list methods and elicitation strategies to measure Chinese apple farmers' risk attitudes and time preferences. Because these farmers can either sell their apples immediately to supermarkets or intermediaries or place them in storage, the authors assess correlations between their storage decisions and their preferences regarding risk and time. The authors also differentiate risks involving gains and losses and empirically examine individual risk attitudes in different scenarios.

Marketing decisions are moderately associated with risk attitudes but not time preference. Farmers with memberships in local farmer cooperatives are likely to speculate more in cold storage. Thus, risk aversion behavioral and psychological motives affect farmers' decision-making of cold storage and intertemporal marketing activities. However, membership in cooperatives does not always result in improved income and welfare for farmers.

The research confirms that behavioral factors may strongly drive vulnerable smallholder farmers to speculate into storage even under seasonal and uncertain marketing volatility. There is the need to think deeper about the rationale of promoting cooperatives and other agricultural forms, because imposing these without careful consideration can have negative impacts.

Do risk and time preferences affect the decision of farmers to utilize storage facilities? This question is important because it is not clear if and how risk preferences affect the tradeoff between consuming today and saving for tomorrow, especially for farmers in developing countries.

The purpose of this paper is to systematically review the published slicing methods for additive manufacturing (AM), especially the multi-direction and non-layerwise slicing methods, which are particularly suitable for the directed energy deposition (DED) process to improve the surface quality and eliminate the usage of support structures.

In this paper, the published slicing methods are clarified into three categories: the traditional slicing methods (e.g. the basic and adaptive slicing methods) performed in the powder bed fusion (PBF) system, the multi-direction slicing methods and non-layerwise slicing methods used in DED systems. The traditional slicing methods are reviewed only briefly because a review article already exists for them, and the latter two slicing methods are reviewed comprehensively with further discussion and outlook.

A few traditional slicing approaches were developed in the literature, including basic and adaptive slicing methods. These methods are efficient and robust when they are performed in the PBF system. However, they are retarded in the DED process because costly support structures are required to sustain overhanging parts and their surface quality and contour accuracy are not satisfactory. This limitation has led to the development of various multi-direction and non-layerwise slicing methods to improve the surface quality and enable the production of overhangs with minimum supports.

An original review of the AM slicing methods is provided in this paper. For the traditional slicing methods and the multi-direction and non-layerwise slicing method, the published slicing strategies are discussed and compared. Recommendations for future slicing work are also provided.

The performance of the first batch of listed companies since the restart of new initial public offerings (IPOs) in January 2014 and their accounting information face repeated and volatile questioning from different sides. This paper aims to take Guirenniao (China) Co. Ltd. (GRN for short), one of the first batch of listed companies in 2014 that suffered performance decline, as an example to analyze how it managed earnings before IPO.

This paper examines earnings management signs that exist in GRN through analysis of its financial statements compared to those of its industry peers. This paper then uses the modified Jones model to detect its accrual earnings management and build three models, which are abnormal levels of cash flows from operations, abnormal production costs and abnormal discretionary expenses, to detect real earnings management.

This paper finds that GRN managed earnings through accrual and real activities in 2012 and 2013. Finally, this paper provides evidence on the specific methods of earnings management, which are easing credit policy to recognize revenue in advance, abnormal expansion, decreasing costs and connected transactions.

This paper examines earnings management signs exist in GRN through analysis of its financial statements comparing to those of its industry peers. This paper then uses the modified Jones Model to detect its accrual earnings management and build three models which are abnormal levels of cash flows from operations, abnormal production costs and abnormal discretionary expenses to detect real earnings management.

The purpose of this paper is to reveal the distributional characteristics and evolutional patterns in source periodicals, topics, authors, funding, and institutes of research papers in Chinese Agricultural Economics so as to understand the current situations and developmental tendency of Chinese agricultural economics research over the past decade.

Using the citation analysis method, this paper analyzed the distributional characteristics and evolution of source periodicals, fields, authors and topics of 2,203 highly cited journal papers from the database of China National Knowledge Infrastructure (CNKI) and 189 cited journal papers from database of Social Sciences Citation Index (SSCI) in agricultural economics first-authored by Chinese scholars from 2006 to 2015.

First, over the past decade, agricultural economics research in China has seen a rapid development. Specially, 103 scholars and 42 institutes have played key roles in the development, and 12 Chinese periodicals and 3 international journals have been the most influential outlets. Second, the coverage of the topics in Chinese agricultural economics research is broad and has expanded over the past decade. The rural land issue has been the most popular topic, while the issues regarding rural institutional arrangements and industrialization in rural areas have been explored extensively. However, issues in other fields, such as agricultural markets and trade, rural labor, food safety, etc. have to be further studied. Third, the improvements of economic theory and quantitative analytic techniques, the supports from research funding, and an increase in the collaboration between Chinese scholars and those from other countries have made great contribution to the rapid development of Chinese agricultural economics research over the past decade.

This paper is an original work that identifies the most influential journal papers including highly cited journal papers from CNKI and cited journal papers from SSCI, using citation frequency and standard Essential Science Indicators method. This is a contribution relative to the methods used by previous studies, which did not account for frequency of citation of a paper. Moreover, this study is based on data from two databases, CNKI and SSCI, suggesting that the coverage of sample papers is broader compared to those of previous studies.

Internationally, microfinance run by non-governmental organizations (NGOs) is often considered an important approach to meeting the credit demand of rural households, particularly among the poor. However, the perceived competitions with formal financial institutions and concerns about financial risks in the rural economy have impeded the development of microfinance by NGOs in China. Despite these concerns about NGO microfinance, little empirical evidence has been brought to prove them. The purpose of this paper is to provide empirical evidence of the relationship between NGO microfinance and farmers’ demand for formal and informal credit in rural China.

The study is based on a household longitudinal data set consisting of 749 households from 40 microfinance villages in rural China. This study draws evidence from China's largest NGO microfinance. Out of the five county branches where China Foundation for Poverty Alleviation has launched institutionalized microfinance since 2006, the authors selected two of them. A random sampling approach was applied in surveying villages and households. In an effort to create impact assessments, the authors surveyed the detailed information on household characteristics and credit access during the period 2006-2009. A panel data is thus structured for the analysis.

The authors found that the demand for credit in rural China is immense and rising, as formal financial institutions have gradually moved away from less developed regions in rural areas. In its place, informal lending has become a primary source of credit for the poor. However, where NGO microfinance has become available, both formal and informal credit has slowed down. The development and expansion of NGO microfinance did stand up as a substitution for institutional lenders and informal financial networks.

The findings have profound policy implications. First, since the development of NGO microfinance fill the demand for credit in rural China and poses low financial risk, the intellectual bias against NGO microfinance is unwarranted. In particular, the regulations that hamper the development of NGO microfinance should be corrected. Second, informal networks do not appear to be costless. Where NGO microfinance can substitute for them, it can mitigate the financial stresses related to the informal credit market.

The purpose of this paper is to analyze the impact of structural changes in hog production manure management practices.

The data used in this study are obtained from a large-scale nationwide hog producers’ survey in rural China conducted by the Center for Chinese Agricultural Policy, Chinese Academy of Sciences, in 2010. A descriptive analysis between hog manure management and its main determinants was conducted. Based on the collected data, an econometric model on the determinants of hog manure management was constructed and used for analysis.

The results of this study suggest that the scale of hog production has an important impact on the pattern of hog manure management. Moreover, the results from descriptive statistics and multivariate estimation suggest that smaller hog producers are more likely to apply hog manure to their own lands, while larger hog producers are more likely to sell the manure or find other ways to dispose of it.

This study contributes to the existing literature by examining the impact of structural changes in hog production on hog manure management and the environment.

The blockchain-based digital twin has been recognized as a prominent technological ecosystem featuring synergies with both established and emergent information management practice. The purpose of this research is to explore the applicability, interoperability and integrability of a blockchain-based digital twin for asset life cycle management and develop a model of framework which positions the digital twin within a broader context of current management practice and technological availability.

A systematic literature review was performed to map use cases of digital twin, IoT, blockchain and smart contract technologies. Surveys of industry professionals and analyses were conducted focussing on the mapped use cases' life cycle–centric applicability, interoperability and integrability with current asset life cycle management practice, exploring decision support capabilities and industry insights. Lastly, a model of framework was developed based on the use case, interoperability and integrability findings.

The results support approaching digitization initiatives with blockchain-based digital twins and the positioning of the concept as both a strategic tool and a multifunctional on-field support application. Integrability enablers include progression towards BIM level 3, decentralized program hubs, modular cross-technological platform interfaces, as well as mergeable and scalable blockchains.

Knowledge of use cases help highlight the functionality of an integrated technological ecosystem and its connection to comprehensive sets of asset life cycle management aspects. Exploring integrability enablers contribute to the development of management practice and solution development as user expectations and technological prerequisites are interlinked.

The research explores asset life cycle management use cases, interoperability and integrability enablers of blockchain-based digital twins and positions the technological ecosystem within current practice and technological availability.