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While an appropriate feed intake is crucial for the reproductive performance of sows, there is a lack of recommendations currently for feed allowance of Guangdong Small-ear Spotted gilts during gestation. The effects of 2 different feeding patterns during gestation on the reproductive performance of Guangdong Small-ear Spotted gilts were investigated by assigning 80 gilts to 2 feeding pattern groups with a randomized complete block design in accordance with initial body weight and back fat thickness, followed by treatment with an incremental feeding pattern (IFP) and a concaved feeding pattern, respectively, with no difference in total feed intake. The IFP group showed a significant decrease in the stillbirth rate (P < 0.05) and an upward trend in piglet mean birth weight (P = 0.06). Furthermore, the IFP group exhibited an increase in the weights of stomach, supraspinatus tendon, triceps, and psoas minor in neonatal piglets (P < 0.05). Overall, the results of the present investigation showed that IFP could significantly reduce the stillbirth rate of Guangdong Small-ear Spotted gilts and increase the muscle weight of progeny.

KEYWORD: partial discharge; online monitoring; onsite detection; HFCT; frequency characteristics ABSTRACT: In the contribution, the equivalent circuit model of high frequency current transform- ers (HFCT), used for partial discharge online monitoring or onsite detecting, is established. Next, the major parameters of HFCT are derived and the influences on amplitude-fre quency and phase- frequency characteristics are discussed. In the end, an optimized design for HFCT is proposed.

It’s the consistency, safety and sustainability of public policy that to some extent determines the effectiveness of policy implementation. This paper focuses on whether we can use formal verification methods to verify the policy implementation consistent with their objectives. Based on a number of policy refinement methods, this paper uses ontology language OWL to break the objectives of public policy into several objects which can be represented by linear temporal logic in the second step for their logical reasons. At last model checking technology is applied to an example to verify the entire process. Then we give the performance analysis of the method and prospects. Keywords-public policy; refinement; OWL; LTL; model checking

Both theoretical and experimental studies of the substrate effect on the thermal behavior of a PbTiO/sub 3/ infrared (IR) sensor have been reported. With active cantilever dimensions of 200/spl times/100/spl times/5 /spl mu/m/sup 3/ formed by etching processes, the pyroelectric micro-electro-mechanical system (pyro/MEMS) structure exhibits a much superior performance to that of a traditional IR-sensing bulk structure under the 800-/spl mu/W incident optical light with wavelength of 970 nm. Two-order improvement in current responsivity is obtained for the pyro/MEMS structure. This shows the substrate effect on the performance of a pyro/MEMS IR sensor is very significant. A simple model has also been proposed to illustrate the substrate effect more comprehensively.

Environmental embrittlement has been demonstrated to be the major cause for brittle fracture and poor ductility at ambient temperature of a number of intermetallic compounds. The kinetics for surface reaction of Fe{sub 3}Al with water vapor and oxygen were studied in this paper using Auger electron spectroscopy (AES). The oxides formed after exposure were analyzed using X-ray photo-electron spectroscopy (XPS). The results obtained were used to explain the different mechanical properties of Fe{sub 3}Al and other intermetallic compounds in various environments.

Cylindrical gel phantoms of 2% agarose concentration were used as wall-less phantoms of arbitrary shape for calibration purposes in non-destructive measurements of bone mineral and heavy metal concentration using XRF. The counts of the coherently and incoherently scattered photons with no sample present should be subtracted as “background” to get a linear relationship between the ratio of the coherently and incoherently scattered photons and the bone mineral concentration for phantoms of arbitrary diameters.

High-power light-emitting diodes (LEDs) modules encapsulated with different lens shapes after a thermal-aging test were studied experimentally and numerically. Samples from different manufacturers were aged at 65, 85, and 95degC under a constant driving current of 350 mA. The results showed that the optical power of the LED modules at the two view angles of plusmn (45deg~75deg) decreased more than the other view angles as the aging time increased. This was due to the reduction of radiation pattern from the corner effect of lens shape, resulted in lower output power. The simulation of the corner effect of lens shape is in good agreement with the experiment result. Results also showed that the center wavelength of the LED spectrum shift 5 nm after thermal aging 600 hours at 95degC because of degradation the lens material. The key module package related failure modes under thermal-aging may be due to the corner effect of lens shape and the degradation of the lens material. Therefore, improving the lens structure and lens material is essential to extend the operating life of the phosphor-based white LEDs modules.

High-power LED modules encapsulated with different lens shapes after a thermal-aging test were studied experimentally and numerically. Samples from different manufacturers were aged at 80, 100, and 120degC under a constant driving voltage of 3.2 V. The results showed that the LED modules encapsulated with a hemispherical-shaped plastic lens exhibited a better lifetime due to their better thermal dissipation than those with cylindrical- or elliptical-shaped plastic lenses. Results also showed that the optical power of the LED modules increased after removing the plastic lens, because the degradation of the material of the plastic lens decreased the amount of light. The key module package related failure modes under thermal-aging were identified as the degradation of the plastic lens and lens material. A finite-element method (FEM) showed that the thermal and major principle stress distributions of the LED modules were significantly dependent on the aging temperature. Both experimental and FEM simulated results clearly indicated that a uniformly thermal dissipation to minimize the thermal effect along the thermal path from the LED chip to the plastic lens is essential to extend the operating life of high-power LED modules.

A new perfusion-based micro three-dimensional (3-D) cell culture platform using enabling microfluidic technology is reported in this study. The platform provides the features of homogenous and well-defined culture environments, efficient medium delivery and "smart cells/agarose (scaffold) loading mechanism", allowing realization of more precise and high-throughput 3-D cell culture-based assay or testing.

This study presents a new chip capable of automating the cell culture process by using microfluidic technology. This microfluidic cell culture system comprising of microheaters, a micro temperature sensor, micropumps, microvalves, microchannels, a cell culture area and several reservoirs was fabricated by using micro-electro-mechanical-systems (MEMS) fabrication processes. Manual cell culture processes can be performed on this chip without using incubators. A typical cell culturing process for human lung cancer cells (A549) was successfully performed to demonstrate the capability of the developed microfluidic system. This automatic cell culturing system can be eventually integrated with subsequent microfluidic modules for cell purification, collection, counting and lysis to form a cell-based micro-total-analysis-system.