In order to solve frequently emerging food safety problems and adapt to the developing trends in the international food safety field, the Chinese government is establishing and developing food traceability systems. Wh...In order to solve frequently emerging food safety problems and adapt to the developing trends in the international food safety field, the Chinese government is establishing and developing food traceability systems. Whether or not food traceability sys- tems can guarantee food safety is a problem well worth discussing. Hence, we constructed a theoretical model to explore the effect of incentives in a food traceability system in order to improve food safety levels. The following results were obtained： enhancing the ef- fectiveness of a food traceability system, increasing the payment to farmers who supply safe agricultural products and strengthening the penalty for unsafe food supply actions are necessary conditions to improve the level of food safety. How to encourage farmers to use food traceability systems is another problem explored in our investigation. Based on a field survey on the willingness of vegetable growers to participate using a vegetable traceability system in Beijing, the first city in China to develop such a system, we used a de- scriptive statistics and a binary logistic regression model to investigate the factors which dominate the decision on the part of farmers to participate in a food safety system. The results indicate that i： younger farmers are more likely to get involved in a food traceability system than older farmers, ii： income from non-agricultural activities decreases the willingness of farmers to participate, iii： the high- er the cost-benefit ratio of growing vegetables, the more likely for farmers to engage in a food traceability system, iv： farmers with a great concern for food safety information have a high propensity to participate and v： increased penalties against unsafe food supply actions and high-risk expectation are adverse incentives. In contrast, high-price expectation is a positive incentive for farmers to par- ticipate, while agricultural training, government subsidies and being part of an industrial organization will significantly strengthen the confidence of farmers to participate in a food safety system.展开更多
To model the operation of food traceability, features of food supply chain are studied. The aim of the paper is to build an abstract model of food traceability, and to gain better understanding of food traceability an...To model the operation of food traceability, features of food supply chain are studied. The aim of the paper is to build an abstract model of food traceability, and to gain better understanding of food traceability and food safety. Based on the analysis of consumers＇ behavior of searching for traceability information, a finite state automaton for food traceability is presented by using automata theory. The states of the food supply chain are represented by a state transition diagram. The automaton in this paper simulates the entire food supply chain and provides a theoretical basis for the behavior description and structural design of a food traceability system.展开更多
Atom lithography with chromium can be utilized to fabricate a pitch standard, which is chrectly traceable to me wavelength of the laser standing waves. The result of a calibrated commercial AFM measurement demonstrate...Atom lithography with chromium can be utilized to fabricate a pitch standard, which is chrectly traceable to me wavelength of the laser standing waves. The result of a calibrated commercial AFM measurement demonstrates that the pitch standard is （212.8±0.1） nm with a peak-to-valley-height （PTVH） better than 20 nm. The measurement results show the high period accuracy of traceability with the standing laser wavelength （λ/2 = 212.78 nm）. The Cr nano-grating covers a 1000μm×500 μm area, with a PTVH better than 10 nm. The feature width broadening of the Cr nanostructure has been experimentally observed along the direction of the standing waves. The PTVH along the Gaussian laser direction is similar to a Gaussian distribution. Highly uniform periodic nanostructures with a big area at the millimeter scale, and the surface growth uniformity of the Cr nano-grating, show its great potential in the application of a traceable pitch standard at trans-scales.展开更多
The line width(often synonymously used for critical dimension,CD)is a crucial parameter in integrated circuits.To accurately control CD values in manufacturing,a reasonable CD reference material is required to calibra...The line width(often synonymously used for critical dimension,CD)is a crucial parameter in integrated circuits.To accurately control CD values in manufacturing,a reasonable CD reference material is required to calibrate the corresponding instruments.We develop a new reference material with nominal CDs of 160 nm,80 nm,and 40 nm.The line features are investigated based on the metrological scanning electron microscope which is developed by the National Institute of Metrology(NIM)in China.Also,we propose a new characterization method for the precise measurement of CD values.After filtering and leveling the intensity profiles,the line features are characterized by the combination model of the Gaussian and Lorentz functions.The left and right edges of CD are automatically extracted with the profile decomposition and k-means algorithm.Then the width of the two edges at the half intensity position is regarded as the standard CD value.Finally,the measurement results are evaluated in terms of the sample,instrument,algorithm,and repeatability.The experiments indicate efficiency of the proposed method which can be easily applied in practice to accurately characterize CDs.展开更多
基金supported by the Program of the National Natural Science Foundation of China(Grant No.70873124)the Specialized Research Fund for the Doctoral Program of Higher Education(Grant No.20070019018)the Philosophy and Social Science Planning Project of Beijing(07BeJG194)
文摘In order to solve frequently emerging food safety problems and adapt to the developing trends in the international food safety field, the Chinese government is establishing and developing food traceability systems. Whether or not food traceability sys- tems can guarantee food safety is a problem well worth discussing. Hence, we constructed a theoretical model to explore the effect of incentives in a food traceability system in order to improve food safety levels. The following results were obtained： enhancing the ef- fectiveness of a food traceability system, increasing the payment to farmers who supply safe agricultural products and strengthening the penalty for unsafe food supply actions are necessary conditions to improve the level of food safety. How to encourage farmers to use food traceability systems is another problem explored in our investigation. Based on a field survey on the willingness of vegetable growers to participate using a vegetable traceability system in Beijing, the first city in China to develop such a system, we used a de- scriptive statistics and a binary logistic regression model to investigate the factors which dominate the decision on the part of farmers to participate in a food safety system. The results indicate that i： younger farmers are more likely to get involved in a food traceability system than older farmers, ii： income from non-agricultural activities decreases the willingness of farmers to participate, iii： the high- er the cost-benefit ratio of growing vegetables, the more likely for farmers to engage in a food traceability system, iv： farmers with a great concern for food safety information have a high propensity to participate and v： increased penalties against unsafe food supply actions and high-risk expectation are adverse incentives. In contrast, high-price expectation is a positive incentive for farmers to par- ticipate, while agricultural training, government subsidies and being part of an industrial organization will significantly strengthen the confidence of farmers to participate in a food safety system.
基金supported by the Science and Technology Public Projects of Sichuan under Grant No. 07GF001-0032010 Ministry of Science and Technology Innovation Fund for SMEs under Grant No. 10C26225123015
文摘To model the operation of food traceability, features of food supply chain are studied. The aim of the paper is to build an abstract model of food traceability, and to gain better understanding of food traceability and food safety. Based on the analysis of consumers＇ behavior of searching for traceability information, a finite state automaton for food traceability is presented by using automata theory. The states of the food supply chain are represented by a state transition diagram. The automaton in this paper simulates the entire food supply chain and provides a theoretical basis for the behavior description and structural design of a food traceability system.
基金supported by the Major Research Plan of the National Natural Science Foundation of China(Grant No.91123022)the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.10804084)
文摘Atom lithography with chromium can be utilized to fabricate a pitch standard, which is chrectly traceable to me wavelength of the laser standing waves. The result of a calibrated commercial AFM measurement demonstrates that the pitch standard is （212.8±0.1） nm with a peak-to-valley-height （PTVH） better than 20 nm. The measurement results show the high period accuracy of traceability with the standing laser wavelength （λ/2 = 212.78 nm）. The Cr nano-grating covers a 1000μm×500 μm area, with a PTVH better than 10 nm. The feature width broadening of the Cr nanostructure has been experimentally observed along the direction of the standing waves. The PTVH along the Gaussian laser direction is similar to a Gaussian distribution. Highly uniform periodic nanostructures with a big area at the millimeter scale, and the surface growth uniformity of the Cr nano-grating, show its great potential in the application of a traceable pitch standard at trans-scales.
基金supported by the National Key Research and Development Program of China(Grant No.2020YFF0218403)the Basic Scientific Research Operating Fund of NIM(Grant No.AKYZD2007-1)。
文摘The line width(often synonymously used for critical dimension,CD)is a crucial parameter in integrated circuits.To accurately control CD values in manufacturing,a reasonable CD reference material is required to calibrate the corresponding instruments.We develop a new reference material with nominal CDs of 160 nm,80 nm,and 40 nm.The line features are investigated based on the metrological scanning electron microscope which is developed by the National Institute of Metrology(NIM)in China.Also,we propose a new characterization method for the precise measurement of CD values.After filtering and leveling the intensity profiles,the line features are characterized by the combination model of the Gaussian and Lorentz functions.The left and right edges of CD are automatically extracted with the profile decomposition and k-means algorithm.Then the width of the two edges at the half intensity position is regarded as the standard CD value.Finally,the measurement results are evaluated in terms of the sample,instrument,algorithm,and repeatability.The experiments indicate efficiency of the proposed method which can be easily applied in practice to accurately characterize CDs.
