基于SCP范式的我国农业产业化分析

以产业组织理论的SCP范式为出发点,分析了我国农业市场结构、行为、绩效的特点,说明在农业产业化过程中,我国农业发展存在集中度过低、产品差异化程度低、劳动力过剩、农业利润率和产业贡献率不足、农户难以适应市场竞争等问题,并为解决这些问题提供了一些政策性建议：加强经营主体联合,发展农村合作组织;促进土地流转,明晰产权制度;加快剩余劳动力转移,降低退出壁垒;加大科技投入,提高科技进步贡献率;改善流通渠道,增强农业竞争力。     

麦长管蚜在不同物候期的3个小麦品种上取食行为的研究

采用刺吸电位(EPG)技术对麦长管蚜在不同物候期的3种不同抗蚜性小麦品种上的取食行为进行了研究.研究发现:麦长管蚜在不同生育期小麦上取食行为差异较大,说明小麦抗性随小麦生长发育有所变化,普遍以穗期抗蚜性最高.其次,根据相关波形出现的频次与时间,可以判断出小麦品种抗蚜机制类型,供试的3种小麦品种的抗蚜机制有所不同:既有以物理抗性为主的品种,也有生化抗性为主的品种.研究结果还表明,小麦对麦长管蚜的生化抗性效果要优于物理抗性.     

鄱阳湖生态经济区农户土地流转行为的实证研究——基于273户农户的调研

为了探讨鄱阳湖生态经济区农地流转的影响因素及其影响机理,笔者以该区273户农户调查数据为基础,利用Logistic模型对农户土地流入和流出的影响因素进行分析。结果表明：（1）户主年龄、户主文化、非农收入比重、农田面积、水利设施年代、有合作组织、是否雇工和补贴政策认知与农户土地流入呈显著的正相关,家庭劳动力、规模认知和借贷难易度与农户土地流入呈显著的负相关,而土地平整状况、水利设施年代、补贴政策认知和销售方式与农户土地流入无关;（2）与农户土地流出呈显著正相关的因素有户主年龄、户主文化、家庭劳动力、非农收入比重、有合作组织和规模认知,水利设施年代、补贴政策认知和销售方式与农户土地流出呈显著的负相关,而农田面积、土地平整状况和是否雇工与农户土地流出无关。农户户主特征及家庭特征对土地流入或流出的决策均有重要的影响,需要引起特别关注。     

Reliability Analysis of Reinforced Concrete Beams Strengthened with CFRP Sheets

The uniaxial load tests were conducted to investigate the material behavior of CFRP sheets. The results show that the probability distribution of CFRP tensile strength can be described by the three-parameter Weibull distribution. The design formulae for determining flexural capacity of reinforced concrete strengthened with CFRP sheet are proposed. The Monte Carlo procedure was applied to simulate the flexural capacity of reinforced concrete strengthened with CFRP sheet. By using the JC method, the reliability index was calculated based on the statistics of flexural capacity and load effect. After the analysis of the effect of the partial factor of CFRP sheet on the reliability index, the results reveal that the reliability index of all design points are the most close to target reliability index overall when the partial factor of CFRP sheet is 1.25,and in this condition the reliability index of three flexural failure modes achieve the target reliability index respectively. Therefore, the partial factor is suggested to be 1.25, which meets the requirement of reliability design.     

中国大螟研究历史、现状与展望

为了深入研究大螟发生特点、探索其危害规律,提出合理有效的防治手段,有效防控大螟危害,笔者以近50年来中国的大螟研究为基础,综述了大螟生物学、生态学、为害特点、防治技术、人工饲养技术、抗药性和毒理以及预测预报等方面取得的进展,并提出了未来大螟研究的方向。     

Acoustic monitoring system to quantify ingestive behavior of free-grazing cattle

Estimating forage intake by free-grazing livestock is difficult and expensive. Previous approaches include behavioral observation, ratio techniques using indigestible markers, mechanical recording of ingestive jaw motion, and acoustic recording of ingestive behaviors. Acoustic recording shows great potential but has been limited by the difficulty and time required to manually identify and classify ingestive events. We present an acoustic recording and analysis system that automatically detects, classifies, and quantifies ingestive events in free-grazing beef cattle. The system utilizes a wide-frequency acoustic microphone close to the animal's mouth, mathematical signal analysis to detect and measure ingestive events, and streaming data analysis capable of handling an unlimited amount of data. Analysis parameters can be reconfigured for different animals, forages and other changing conditions. The system measures the acoustic parameters of ingestive events, such as duration, amplitude, spectrum and energy, which can support further event classification and become the inputs to a forage intake model. We validated our detection and classification technique against the results of trained human observers based on field studies with grazing steer. The software detected 95% of manually identified bites in an event-by-event comparison. Field observations and sound attenuation analysis indicate that sounds from adjacent livestock and ambient pastoral environments have an insignificant effect upon the integrity of the recorded acoustic data set. We conclude that wideband acoustic analysis allows us to identify ingestive events accurately and automatically over extended periods of time.     

A real-time automated system for monitoring individual feed intake and body weight of group housed turkeys

Feed conversion is an important production trait in turkey breeding; the measurement of an individual bird's feed efficiency is important in identifying the most genetically superior individual. The development of a real-time automated feed intake and body weight monitoring system is described in this paper. The system integrated multiple feed and body weight weighing stations consisting of electronic scales, radio frequency identification (RFID) devices and data communication modules. A distributed and client-server-based system architecture with multi-threading software design was developed. This system architecture allowed for a real-time data acquisition capability when a large number of stations were required. A structured query language (SQL) database management system was developed to record and manage the dynamic feed intake and body weight gain data of individual birds. The developed system also offers a powerful research tool for studying poultry feeding behavior under group housing conditions.     

农村社区青少年越轨行为的预防与控制模式探析

针对当前农村青少年的灰恶化局面,分析了传统农村社区青少年越轨行为的预防与控制模式的建构逻辑、维系与再生产,构建了以民主与法制为基础．社区、家庭和各种农村青少年接纳组织相互协作的新型农村社区青少年越轨行为的预防与控制模式。     

甲壳素对铜的吸附性能研究

研究了甲壳素吸附铜离子的过程。结果表明：甲壳素对铜离子的吸附在pH=4．46时最佳,在298K下测得静态饱和吸附容量为317．2mg／g（树脂）。用1．0mol／LHCl可洗脱,洗脱率达97．4％;测得表观速率常数k298=1．34×10-4/s;表观活化能Ea=26．1kJ／mol;等温吸附服从Freundlich经验式;吸附热力学参数△H=11-3kJ／mol,△S=42．6J／（mol·K）,AG=-1．4kJ／mol。     

中小城市乡村旅游行为轨迹机理比较研究——以莆田市滨海与森林公园所在乡（镇）为例

在实地问卷调研和专家访谈的基础上,以福建省莆田市滨海乡（镇）、森林公园为研究区域,对调查样本人口学特征进行对比分析后,从旅游信息的收集与处理、旅游动机的激发、旅游目的地的选择、旅游消费水平与偏好、出游方式和频率、游客亲疏度和客源地等方面比较中小城市乡村旅游的游客行为轨迹机理,为乡村旅游深度开发、目标定位、旅游营销等提供决策依据。