Grain-yield prediction using remotely sensed data have been intensively studied in wheat and maize, but such information is limited in rice, barley, oats and soybeans. The present study proposes a new framework for rice-yield prediction, which eliminates the influence of the technology development, fertilizer application, and management improvement and can be used for the development and implementation of provincial rice-yield predictions. The technique requires the collection of remotely sensed data over an adequate time frame and a corresponding record of the region's crop yields. Longer normalized-difference-vegetation-index (NDVI) time series are preferable to shorter ones for the purposes of rice-yield prediction because the well-contrasted seasons in a longer time series provide the opportunity to build regression models with a wide application range. A regression analysis of the yield versus the year indicated an annual gain in the rice yield of 50 to 128 kg ha−1. Stepwise regression models for the remotely sensed rice-yield predictions have been developed for five typical rice-growing provinces in China. The prediction models for the remotely sensed rice yield indicated that the influences of the NDVIs on the rice yield were always positive. The association between the predicted and observed rice yields was highly significant without obvious outliers from 1982 to 2004. Independent validation found that the overall relative error is approximately 5.82%, and a majority of the relative errors were less than 5% in 2005 and 2006, depending on the study area. The proposed models can be used in an operational context to predict rice yields at the provincial level in China. The methodologies described in the present paper can be applied to any crop for which a sufficient time series of NDVI data and the corresponding historical yield information are available, as long as the historical yield increases significantly.

Motor vehicles are the major source of urban air pollution. The abatement of air pollutant emissions is an urgent task for environmental protection. This paper simulated the abatement for carbon monoxide (CO), volatile organic compounds (VOCs), nitrogen oxides (NO x ), and particular matter (PM) emissions from vehicles under four scenarios in the year 2015 in Hangzhou, China. It was found that the emissions of CO, VOCs, NO x , and PM from vehicles were 440.551, 23.079, 44.255, and 6.532 kt/a in 2010 in Hangzhou, respectively. The vehicle population will increase to over 1.2 million with a 60.7% growth rate until 2015 (estimated). Based on the scenario analysis, it was found that eliminating substandard vehicles and upgrading vehicle's standards could help reduce CO and VOCs effectively, while the expected abatement of NO x and PM would be offset by the rapid increase in the vehicle numbers. It was also found that integrated measurements, including eliminating substandard vehicles, upgrading vehicle standards, supplying low sulfur oil, and introducing alternative fuel vehicles could simultaneously reduce the four key pollutants. These integrated policies make it possible to reduce 250.197, 10.270, 1.791, and 0.335 kt/a CO, VOCs, NO x , and PM with 56.79%, 44.50%, 4.05%, and 5.14% decrease rates in 2015, respectively, when compared to those in 2010.

Fresh pork is a meat that many people choose to eat in daily lives, and it is becoming more important to devise a method for ensuring the quality and safety of fresh pork. Combined with the meat quality of the cold chain and the environmental information collection program, this study presents a QR code based tracing method for a quality tracing system. This method includes a correction recognition test for the final design of the QR code. The results show that QR code can store large amounts of traceability information, with strong error correction capability, and can provide a great advantage in scanning recognition. In the process of consumption, consumers can easily obtain fresh pork quality information by scanning the QR code with a mobile phone, rather than having to choose a piece of meat to purchase based only on a visual observation of the meat. Practical applications In this study, the design of the temperature acquisition scheme was verified in SMEs (small and medium enterprises), the results show that the data transmission is stable. The generated QR codes were tested in some supermarkets, have strong error correction capability, and can meet the retroactive requirements. According to this research, when the damage to the traceability barcode is beyond the range of 30% before the barcode enters circulation, the barcode needs to be reprinted.

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A portable and flexible self-powered biosensor based on ZnO nanowire arrays (ZnO NWs) and flexible PET substrate has been designed and fabricated for real-time monitoring in swimming. Based on the piezoelectric effect of polar ZnO NWs, the fabricated biosensor can work in both air and water without any external power supply. In addition, the biosensor can be easily attached to the surface of the skin to precisely monitor the motion state such as joint moving angle and frequency during swimming. The constant output piezoelectric signal in different relative humidity levels enables actual application in different sports, including swimming. Therefore, the biosensor can be utilized to monitor swimming strokes by attaching it on the surface of the skin. Finally, a wireless transmitting application is demonstrated by implanting the biosensor in vivo to detect angiogenesis. This portable and flexible self-powered biosensor system exhibits broad application prospects in sport monitoring, human–computer interaction and wireless sport big data.

Dry sliding wear tests were performed for 7075 Al alloy under a load of 25-250 N at 25-200°C. The wear behaviors and mechanisms under various testing conditions were explored. A mild-to-severe wear transition is noticed to occur with an increase in the load at 25-200°C. With the temperature increasing, the wear loss decreases constantly under the low load of less than 50 N. It can be suggested that the 7075 Al alloy presents a high wear resistance under a high ambient temperature and low load. Its high wear resistance is found to be attributed to the existence of mechanically mixing layer (MML). The predominant wear mechanism is adhesive and abrasive wear at room temperature. With the ambient temperature and load increasing, oxidative wear and plastic extrusive wear successively prevail due to thermal oxidation and softening of matrix.

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