Relative Efficiency of Selection Methods for Profit in Dairy Cows

Selection singly on milk yield and calculated profitability traits, selection indexes, and regression indexes were compared for the relative gains in expected profit to 72 mo of age or life time profit. Indexes consisted of five traits of the first lactation: milk, fat percent, days in milk, number of breedings, and age at first calving. The study was on 1806 Holstein cows sired by 404 bulls in 38 California herds. Genetic gain in total profit was 13 to 14% greater when selection was on estimated profit to 41 mo than on milk yield to 305 days in the first lactation. Selection on traits of estimated profit on three bases, to 305 days in first lactation, to end of first lactation, and to 41 mo of age was 2 to 14% more efficient for genetic gain in total profit than selection on corresponding traits of milk yield or selection indexes. Regression indexes were 3 to 19% more efficient than selection indexes for predicting subsequent cumulative profit. In contrast, selection indexes were 6 to 20% more efficient than regression indexes for genetic gain in total profit. Heritabilities for estimated profit and traits of milk yield in the first lactation ranged from .26 to .49 for cows with two or more calvings. Heritabilities for profit to end of first lactation and to 41 mo of age exceeded comparable milk yield traits by 15 to 27%. The economic value of a 1-mo decrease in age at first calving was equivalent to an increase of 138 kg milk yield to the end of the first lactation for gain in total profit to 72 mo of age. Similarly, the genetic effects, or relative selection value, of a 1-mo decrease in age at first calving is valued at approximately 471 kg milk.     

NONLINEAR VISCOELASTIC MODEL CONTAINING A YIELD ELEMENT FOR MODELING A FOOD MATERIAL1

A series-parallel model is introduced in which a yield element is incorporated in the parallel branch. Before the yield stress is reached, the stress-strain behavior is determined by the series branch to exhibit the linear uiscoelasticity of the material. When the yield stress is reached, the stress in the model which was sustained by the yield element is suddenly transferred to the spring and dashpot in parallel. As a consequence, a stress rate discontinuity was created. It is this feature which makes possible the simulation of the yield behavior of the food material. Data from Instron tests on American cheese are used to illustrate the model.     

The Ga−Sb (Gallium-Antimony) system

R. C. Sharma was Visiting Assistant Professor (1984–1986)     

Self-aligned inversion n-channel In0.2Ga0.8As/GaAs metal–oxide–semiconductor field-effect-transistors with TiN gate and Ga2O3(Gd2O3) dielectric

A self-aligned process for fabricating inversion n-channel metal–oxide–semiconductor field-effect-transistors (MOSFET’s) of strained In_0.2Ga_0.8As on GaAs using TiN as gate metal and Ga₂O₃(Gd₂O₃) as high κ gate dielectric has been developed. A MOSFET with a 4 μm gate length and a 100 μm gate width exhibits a drain current of 1.5 mA/mm at V_g = 4 V and V_d = 2 V, a low gate leakage of <10^?7 A/cm² at 1 MV/cm, an extrinsic transconductance of 1.7 mS/mm at V_g = 3 V, V_d = 2 V, and an on/off ratio of ～10⁵ in drain current. For comparison, a TiN/Ga₂O₃(Gd₂O₃)/In_0.2Ga_0.8As MOS diode after rapid thermal annealing (RTA) to high temperatures of 750 °C exhibits excellent electrical and structural performances: a low leakage current density of 10^?8–10^?9 A/cm², well-behaved capacitance–voltage (C–V) characteristics giving a high dielectric constant of ～16 and a low interfacial density of state of ～(2～6) × 10¹¹ cm^?2 eV^?1, and an atomically sharp smooth Ga₂O₃(Gd₂O₃)/In_0.2Ga_0.8As interface.     

Capturing device mismatch in analog and mixed-signal designs

As feature size goes below 70 nm, process variation introduced device mismatch may cause over 40% performance variations and circuit failures especially for analog/mixed-signal designs. The location dependent correlations among devices and the large number of devices in some practical designs make it difficult to predict performance corners accurately and efficiently. This paper aims to provide an overview of possible methodologies and approaches that model and analyze device mismatch. In particular, the paper describes a new finite point device modeling technique that can speed up the analysis procedure, a new parametric reduction method and a novel Chebyshev Affine Arithmetic (CAA) based performance bound estimation approach.     

Dual Partial Dye Doping for Chromaticity Tuning and Performance Enhancement of White OLEDs

In general, a guest dopant is doped into a single host matrix for white-light emission with two complementary colors. In this work, however, we have fabricated a white organic light-emitting diode (WOLED) based on dual partial dye doping in which a guest dopant is partially doped into two different host emitters; namely, orange-red emitting 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminos-tyryl)-4H-pyran (DCM) is partially doped into both blue-emitting 4, 4'-bis(2,2'-diphenylvinyl)-1,1'-biphenyl (DPVBi) and green-emitting Tris-(8-hydroxyquinoline) aluminum (Alq₃). We demonstrate that dual partial dye doping allows us to finely tune the Commission Internationale d'Eclairage (CIE) chromaticity coordinates to the equienergy white point (x = 0.33, y = 0.33). In addition, it enhances device performance further, compared to WOLEDs based on DCM partially doped into a single host matrix (either DPVBi or Alq₃). Moreover, the dual partial doping scheme is shown to provide a way of suppressing the self-quenching effect (singlet-singlet annihilation). For a systematic study, we have implemented a comprehensive numerical model and performed simulations of the OLED structure, providing a clear understanding with regard to the underlying physics of OLEDs. We also carry out an investigation of the effects of key design parameters such as the doped layer position and thickness and dye.     

Effect of Al Composition and Gate Recess on Power Performance of AlGaN/GaN High-Electron Mobility Transistors

AlGaN/GaN high-electron mobility transistors with different Al compositions and barrier thicknesses were compared. The samples with higher Al composition and similar 2D electron gas density showed higher gate leakage, utilizing a slant field plate gate process. By applying a gate recess etch and a slant field plate gate process, gate leakage was improved to a similar level for all the devices, and the power density and PAE were much improved.     

Investigation of the Interfaces in Ni-FUSI/Hf-Based/Si and Ni-FUSI/SiO<Subscript>2</Subscript>/Si Stacks by Physical and Electrical Characterization Techniques

The combination of full Ni silicidation (Ni-FUSI) gate electrodes and hafnium-based high-k gate dielectrics is one of the most promising replacements for poly-Si/SiO₂/Si gate stacks for the future complementary metal–oxide–semiconductor (CMOS) sub-45-nm technology node. The key challenges to successfully adopting the Ni-FUSI/high-k dielectric/Si gate stack for advanced CMOS technology are mostly due to the interfacial properties. The origins of the electrical and physical characteristics of the Ni-FUSI/dielectric oxide interface and dielectric oxide/bulk interface were studied in detail. We found that Ni-FUSI undergoes a phase transformation during silicide formation, which depends more on annealing temperature than on the underlying gate dielectric material. The correlations of Ni–Si phase transformations with their electrical and physical changes were established by sheet resistance measurements, x-ray diffraction (XRD), atomic force microscopy (AFM), and x-ray photoelectron spectroscopy (XPS) analyses. The leakage current density–voltage (J–V) and capacitance–voltage (C–V) measurement techniques were employed to study the dielectric oxide/Si interface. The effects of the postdeposition annealing (PDA) treatment on the interface charges of dielectric oxides were studied. We found that the PDA can effectively reduce the trapping density and leakage current and eliminate hysteresis in the C–V curves. In addition, the changes in chemical bonding features at HfO₂/Si and HfSiO/Si interfaces due to PDA treatment were evaluated by XPS measurements. XPS analysis provides a better interpretation of the electrical outcomes. As a result, HfSiO films exhibited superior performance in terms of thermal stability and electrical characteristics.     

Dominant mechanisms of transient-radiation upset in CMOS RAM VLSI circuits realized in SOS technology

The dominant mechanisms are analyzed of transient-radiation upset in CMOS RAM VLSI circuits realized in SOS technology. Data reliability under transient irradiation is discussed in relation to photocurrents, rail-span collapse, and the circuit and layout design of memory cells. The response is simulated of SOS integrated resistors to transient radiation. Optimal parameter values are thus determined for the resistor used in the RC network of a memory cell. It is found that the data reliability of the memory circuits considered is affected by the cross coupling of memory cells sharing a read/write line. The lifetime of radiation-induced charge carriers is estimated by experiment and computer simulation.