Genetic parameters for udder morphology traits either subjectively assessed or exactly measured, and a combination of both sets of traits were estimated using multi-trait animal model and algorithm REML （program VCE ...Genetic parameters for udder morphology traits either subjectively assessed or exactly measured, and a combination of both sets of traits were estimated using multi-trait animal model and algorithm REML （program VCE 4.0）. Purebred Tsigai and Improved Valaehian breeds, and crossbreds with Lacaune and East Friesian were studied. Subjectively assessed traits included udder depth （UD）, cistern depth （CD）, teat placement （TP）, teat size （TS）, udder cleft （UC）, udder attachment （UA） and udder shape （US）. Exact measurements included udder length （UL）, udder width （UW）, udder depth （UDEx）, cistern depth （CDEx）, teat length （TL） and teat angle （TA）. Heritabilities estimated for subjectively assessed traits were lower than those estimated for exact measurements and ranged from 0.090 （UA） to 0.294 （CD）. Heritabilities estimated for exact measurements ranged from 0.102 （UW） to 0.448 （CDEx）. In simultaneous evaluation of four subjectively assessed traits and corresponding exact measurements, heritabilities remained almost the same. High genetic correlations （0.855 to 0.937） between UD and UDEx, CD and CDEx, TS and TL and between TP and TA were found. These findings allow presuming that genetic evaluation based on subjectively assessed traits could become an effective tool in selection programs aimed at improvement of udder morphology in dairy ewes.展开更多
Windbelt generators have been proposed as small, green power sources for battery charging applications. Some of the reported results lack detailed information about how key parameters influence the output power of the...Windbelt generators have been proposed as small, green power sources for battery charging applications. Some of the reported results lack detailed information about how key parameters influence the output power of the generator. In this work, we built prototypes with different architectures to study the voltage generation and power delivery as functions of belt tension, length, and electrical load at various wind speeds. We also studied the maximum power delivery conditions before the breakdown of the belt oscillation occurs. Our results are obtained from windbelt generators with two types of architectures： a conventional design with an adjustable belt that uses weight for tension control, and a revised design with a belt oscillation perpendicular to the coil axis. We have concluded that the breakdown of the belt oscillation at lower output resistances is a primary bottleneck that will limit windbelt systems to only very low power applications.展开更多
This paper establishes a new framework for modeling electrical cyber-physical systems(ECPSs),integrating both power grids and communication networks. To model the communication network associated with a power transmis...This paper establishes a new framework for modeling electrical cyber-physical systems(ECPSs),integrating both power grids and communication networks. To model the communication network associated with a power transmission grid, we use a mesh network that considers the features of power transmission grids such as high-voltage levels, long-transmission distances, and equal importance of each node. Moreover, bidirectional links including data uploading channels and command downloading channels are assumed to connect every node in the communication network and a corresponding physical node in the transmission grid. Based on this model,the fragility of an ECPS is analyzed under various cyber attacks including denial-of-service(Do S) attacks, replay attacks, and false data injection attacks. Control strategies such as load shedding and relay protection are also verified using this model against these attacks.展开更多
文摘Genetic parameters for udder morphology traits either subjectively assessed or exactly measured, and a combination of both sets of traits were estimated using multi-trait animal model and algorithm REML （program VCE 4.0）. Purebred Tsigai and Improved Valaehian breeds, and crossbreds with Lacaune and East Friesian were studied. Subjectively assessed traits included udder depth （UD）, cistern depth （CD）, teat placement （TP）, teat size （TS）, udder cleft （UC）, udder attachment （UA） and udder shape （US）. Exact measurements included udder length （UL）, udder width （UW）, udder depth （UDEx）, cistern depth （CDEx）, teat length （TL） and teat angle （TA）. Heritabilities estimated for subjectively assessed traits were lower than those estimated for exact measurements and ranged from 0.090 （UA） to 0.294 （CD）. Heritabilities estimated for exact measurements ranged from 0.102 （UW） to 0.448 （CDEx）. In simultaneous evaluation of four subjectively assessed traits and corresponding exact measurements, heritabilities remained almost the same. High genetic correlations （0.855 to 0.937） between UD and UDEx, CD and CDEx, TS and TL and between TP and TA were found. These findings allow presuming that genetic evaluation based on subjectively assessed traits could become an effective tool in selection programs aimed at improvement of udder morphology in dairy ewes.
文摘Windbelt generators have been proposed as small, green power sources for battery charging applications. Some of the reported results lack detailed information about how key parameters influence the output power of the generator. In this work, we built prototypes with different architectures to study the voltage generation and power delivery as functions of belt tension, length, and electrical load at various wind speeds. We also studied the maximum power delivery conditions before the breakdown of the belt oscillation occurs. Our results are obtained from windbelt generators with two types of architectures： a conventional design with an adjustable belt that uses weight for tension control, and a revised design with a belt oscillation perpendicular to the coil axis. We have concluded that the breakdown of the belt oscillation at lower output resistances is a primary bottleneck that will limit windbelt systems to only very low power applications.
基金Project supported by the National Basic Research Program(863)of China(No.2015AA05002)the National Natural Science Foundation of China(No.61471328)the Science and Technology Project of State Grid,China(No.XXB17201400056)
文摘This paper establishes a new framework for modeling electrical cyber-physical systems(ECPSs),integrating both power grids and communication networks. To model the communication network associated with a power transmission grid, we use a mesh network that considers the features of power transmission grids such as high-voltage levels, long-transmission distances, and equal importance of each node. Moreover, bidirectional links including data uploading channels and command downloading channels are assumed to connect every node in the communication network and a corresponding physical node in the transmission grid. Based on this model,the fragility of an ECPS is analyzed under various cyber attacks including denial-of-service(Do S) attacks, replay attacks, and false data injection attacks. Control strategies such as load shedding and relay protection are also verified using this model against these attacks.
