A Perspective on Organic Agriculture in China - Opportunities and Challenges

With the rapid development of international production and trade in organic food, organic agriculture is also boosting in China. The milestone of Chinese organic agri-culture was set in 1990 with the first export of a certified organic product (tea) from Lin’an county of Zhejiang Province, China, which marked the launch of organic pro-duction in China. By the end of 2005, there had been about 4.384 million ha organic land, including 1.694 million ha organic, 0.61 million ha conversion as well as 2.08 million ha collection area, about half of which is certified area. About 4.93 million tons organic products and nearly 1600 projects had been certified with 300~400 varieties. According to the above data, now China ranks the 3rd largest country of organic production in the world. In China, organic development mostly is export oriented, the export products include beans, rice, tea, mushroom, vegetable, processed oil and herbs, etc. According to the certifying body COFCC of Ministry of Agriculture (MOA), the value of exported organic products increased from 0.3 million USD in 1995 to 0.35 billion USD at the end of the year 2004. Chinese domestic organic market started from 2000. Presently, most of the products sold in domestic markets are certified by COFCC and OFDC in some largest cities such as Beijing, Shanghai, Guangzhou, Nanjing and Shenzhen, etc. The price of the organic products is often up to 3 times the price of conventional products. Average organic food consumption accounts for 0.08% of the conventional food (LI 2006)

Crime Analysis of Chicago

Security status in the place where we are live is one of the most important concerns for every individual. As most people may know, to evaluate the security status, criminal rate cannot be overlooked. Many factors can influence the occurrence of crimes including time, places, the construction of population, educational level, income level and so on. Nowadays, using modern technology such as Hadoop to process large volume of crime dataset, analyze the relationship between crime rate and the related factors and predict the happen of crime are getting more and more popular. In this project, using Hadoop ecosystem and related technologies, we choose crimes dataset of Chicago from 2001 to present to analyze the relationships between the occurrence of crimes and several key factors

Simulation of the Superheated Water Expansion Process in a Cylinder with Moving Piston

The Trilateral cycle has attracted more and more attentions because of its better temperature profiles matching in the heater compared to conventional heat recovery cycles, such as the Organic Rankine Cycle and the Kalina Cycle. However, the actual fundamentals of the two-phase expansion process have not been clarified, especially, the evolution mechanisms of the evaporating rate and the degree of superheat during the expansion process are indistinct. In the present study, two-phase expansion process of superheated water in a cylinder with moving piston was analyzed. A model was proposed to calculate the evaporating rate and the degree of superheat of liquid water. A semiempirical Nusselt number was adopted to solve the energy conservation equations. It was shown that the degree of superheat of liquid water was increased rapidly to the maximum at the beginning of the expansion process and then was decreased continuously. The degree of superheat was almost equal to 0 at the end of the expansion process. The simulation results also showed a complex evolution profile of the evaporating rate during the expansion process. As a whole, the evaporating rate was increased from 0 to the maximum, and then it was decreased to 0 at the end of the expansion process. This situation is similar to the experimental results in the published literature. The evaporating rate appeared a transient dropping process at the beginning of the expansion. It was considered that this result was associated with the rapid decline of the degree of superheat. Meanwhile, there were two or three significant inflection points on the evolution profile. From the model prediction, it was concluded that the evaporating rate may be related to the degree of superheat of liquid water, the piston velocity and the mass of liquid water in the cylinder

Positive radial solutions for a class of quasilinear Schrödinger equations in R3

This paper is concerned with the following quasilinear Schrödinger equations of the form: −∆u − u∆(u 2 ) + u = |u| p−2u, x ∈ R 3 where p ∈ (2, 12). By making use of the constrained minimization method on a special manifold, we prove that the existence of positive radial solutions of the above problem for any p ∈ (2, 12)