Relations among homogeneity, collapsibility and nonconfounding in distribution effects

In this paper, the concept of distribution effect is proposed without the causal diagram. Following the notation of Stone [11], we assume that the exposure treatment X is an unknown deterministic function of the confounder set Pa（X） and a random error ε. We discuss sufficient and necessary conditions for homogeneity, collapsibility and nonconfounding for distribution effects and discuss relations among them.

Particle Size Distribution,Powder Agglomerates and Their Effects on Sinterability of Ultrafine Alumina Powders

An intensive study of the particle size distribution of four commercial ultrafine alumina powders to obtain information about the powder agglomeration and relate them to the compactibility and the sinterability has been made.

Effects of Land-Sea Distribution, Topography and Diurnal Change on Summer Monsoon Modeling

The effects of the land-sea distribution, the topography and the diurnal change of the solar radiation on the summer monsoon modelings are studied by use of a coupled modeling system with a 5-layer primitive equation model of the atmosphere and a 2-layer soil or ocean thermodynamic model which are all solved in a zonal model domain between 60°S and 60°N. The results of numerical simulations show that the quasi-stationary patterns of the mean monsoon circulations are mainly affected by the land-sea distribution and the topography, the effect of the diurnal change is the secondary. However, the inclusion of the diurnal change into the model system may improve the intensity of the simulated monsoon circulation, it can influence the distributive pattern of precipitation to a larger extent,without the diurnal change precipitation in the interior of land would decrease and in the coastal regions it would increase.

Effect of Nickel Distributions Embedded in Amorphous Carbon Films on Transport Properties

Electrical properties of C/Ni films are studied using four mosaic targets made of pure graphite and stripes of nickel with the surface areas of 1.78,3.21,3.92 and 4.64%.The conductivity data in the temperature range of400-500 K shows the extended state conduction.The conductivity data in the temperature range of 150-300 K shows the multi-phonon hopping conduction.The Berthelot-type conduction dominates in the temperature range of 50-150 K.The conductivity of the films in the temperature range about 〈 50 K is described in terms of variable-range hopping conduction.In low temperatures,the localized density of state around Fermi level（F）for the film deposition with 3.92% nickel has a maximum value of about 56.2×10^（17）cm^（-3）eV^（-1） with the minimum average hopping distance of about 3.43 × 10^（-6） cm.

Effects of Distribution of Induced Defects on Positron Diffusion

The effects of distribution of induced defects on the positron diffusion was studied by using the point-source diffusion model and 6 function method.

Relativistic and distorted wave effects on Xe 4d electron momentum distributions

The relativistic and distorted wave effects are investigated for the electron momentum distributions of Xe 4d electrons.The theoretical results show good agreements with the experimental data measured previously with electron momentum spectroscopy. The distorted wave effect and the relativistic effect are found to play important roles in the low and high momentum regions, respectively.

The Effectiveness of Cyclic Blockwise Distribution

In spite of the wealth Of existing data distribution methods, most parallel programming languages support only some form of cyclic blockwise distribution. The main reason why only this single method is supported is that it is relatively simple to implement. However, it is as yet nuclear whether cyclic blockwise distribution is sufficiently powerful for a wide class of distribution problems. In this paper the method will be analysed, showing that for a wide range of problems it is indeed sufficient. It will also be shown in which cases cyclic blockwise distribution can be effected to fail. From this analysis, it is possible to formulate practical guidelines to assist Programmers in choosing the cycle frequency for cyclic blockwise distribution that leads to an optimal result.

Spatial Distribution Pattern of the Steppe Toad-headed Lizard(Phrynocephalus frontalis) and Its Influencing Factors

Spatial distribution patterns are associated with life history and behavioral adaptations of animals. For studying the spatial distribution pattern of the steppe toad-headed lizard(Phrynocephalus frontalis) and its influencing factors,we conducted experiments in Hunshandake Sandy Land in Inner Mongolia,China in July 2009. By calculating the clustered indices,we found that the lizard was aggregately distributed when the sampling quadrat was smaller than 10 m × 10 m,and uniformly distributed when it was greater than 10 m × 10 m. The Nearest Neighbor Rule showed a clustering distribution pattern for P. frontalis and the distribution pattern was quadrat-sampling dependent. Furthermore,the cluster was determined by environmental factors when the sampling quadrat was smaller than 20 m × 20 m,but it was determined by both environmental factors and characteristics of the lizard when it was larger than 20 m × 20 m. Our results suggested that the steppe toad-headed lizards tended to aggregate into suitable habitat patches in desert areas. Additionally,we discussed that the lizard aggregation could be potentially used as an indictor of movement of sand dunes.

Improved high-frequency equivalent circuit model based on distributed effects for SiGe HBTs with CBE layout

In this paper, we present an improved high-frequency equivalent circuit for SiGe heterojunction bipolar transistors（HBTs） with a CBE layout, where we consider the distributed effects along the base region. The actual device structure is divided into three parts： a link base region under a spacer oxide, an intrinsic transistor region under the emitter window,and an extrinsic base region. Each region is considered as a two-port network, and is composed of a distributed resistance and capacitance. We solve the admittance parameters by solving the transmission-line equation. Then, we obtain the smallsignal equivalent circuit depending on the reasonable approximations. Unlike previous compact models, in our proposed model, we introduce an additional internal base node, and the intrinsic base resistance is shifted into this internal base node,which can theoretically explain the anomalous change in the intrinsic bias-dependent collector resistance in the conventional compact model.

Analysis of the negative effects of groundwater exploitation on geological environment in Asia

This paper summarizes the negative effects on geological environment caused by groundwater exploitation and its distribution. There are seven main types of the geological environment negative effects, which are generally as follows:(1) Constant decrease of groundwater level is mainly distributed in China(East Asia), India(South Asia), Tajikistan(Central Asia) and Saudi Arabia(West Asia);(2) land subsidence occurs mainly in eastern plains of East Asia and west Siberian Plain of North Asia;(3) seawater intrusion occurs mainly in China, Japan and South Korea in East Asia, Philippines and Indonesia in Southeast Asia, the Indian coastal areas in South Asia;(4) groundwater level decline caused by groundwater exploitation in oil fields;(5) mining collapse is mainly in 50° to 70° north latitude band;(6) the total area of karst collapse in China of East Asia is as much as 197.05 km^2; and(7) ground fracture is mainly distributed in the North China Plain, Fenwei Plain and the Yangtze River Delta. Asia can be divided into 6 zones in terms of the geological environment negative effect caused by groundwater exploitation. According to analysis, with the increasing intensity of human activities, geological environment issues become more and more serious, therefore it is vital to control the human activities within the scope of 5× 10~5 people/km^2 to 9.9× 10~5 people/km^2 for the effective control of the size of the affected area by geological environment problems.

Why are There Indica Type and Japonica Type in Rice?——History of the Studies and a View for Origin of Two Types

On the bases of archaeological discoveries, the earliest domestication of rice has been confirmed in the middle and lower Changjiang River basin, while in the region wild rice populations are found in shallow swamps under a climate with freezing winter cold. These findings lead us to-examine the past ideas about domestication and differentiation of rice. Historically, in 1930s two sub-species, indica and japonica, were proposed on the basis of sterility in F1 hybrids between them. Soon after that, the two types were classified by the associations of a number of genetically independent traits. The characteristic associations of traits have been explained by the hybrid sterility or reproductive barriers which were assumed to comprise a set of duplicate recessive lethal genes and to be an inner genetic mechanism to lead to the varietal differentiations In 1980s, the hybrid sterility between Indica and Japonica types was analyzed, and Indica, Japonica, and wide-compatibility type which gives fertile hybrids when cross to Indica and Japonica types, are proved to contain an allele, S5＇, S5＇ and S5^n, respectively at a locus on chromosome 6. And those gametes having Sj allele are found to be partially aborted in the hybrid genotypes of S5＇/S5＇ while no gamete abortion occurs in S5＇/S5^n and S5＇/S5^n genotypes. Since then, the gene S5^n has been used in hybrid rice breeding to obtain fertile and vigorous hybrids between subspecies, and the long-disputed problem of hybrid sterility has been solved. Also in such studies the characteristic association of traits found in each of vadetal groups is better explained by founder effects. On the other hand, a large number of native cultivars of rice were surveyed with enzyme polymorphism in 1980s and later with molecular markers. As a result, profound genetic diversity is found in cultivated rice as well as in wild rice. These findings seem to lead us to the idea of multiple independent domestications of rice. However, before reaching such a conclusion, at least two factors, i.e., long-distance-dissemination of some genotypes and the possibilities of introgression by local wild rice to primitive cultivars need to be examined. Taking the two factors as well as the historical events into consideration, it is considered here that the perennial japonica cultivars which are close to wild rice in the Changjiang River basin were disseminated to East India through Assam or along the Bengal Bay, where they were transformed under the introgressions of local wild rice and formed a secondary center, from which some genotypes seem to be disseminated to colonies in Southeast Asia under the influence of Hinduism. Later some of the genotypes were introduced into China and constituted so called Indica type. This may be a reasonable picture for the varietal differentiation.

Process parameters influence on zone refining and thermodynamics analysis of 1,2-diphenylethane

Effective distribution coefficients of 9 impurities in 1,2-diphenylethane have been calculated by directional crystallization under different ambient frozen temperature.The effect of varied zone size,temperature difference between the melt and ambient frozen environment,number of zone on purity of 1,2-diphenylethane have been also investigated during the process of zone refining.The results indicate that the product purity in the intermediate purified region with varied zone size is higher 0.04%–0.2%than that with constant zone size.The product purity increases with temperature difference between the melt and ambient frozen environment.The appropriate temperature difference is adopted 50°C.The product purity in the intermediate region of sample bar with 2 molten zones is higher 0.05%–0.43%than that with 1 molten zone.In addition,the change of enthalpy and entropy between impurities and 1,2-diphenylethane have been determined.

High-speed and high-performance polarization-based quantum key distribution system without side channel effects caused by multiple lasers

Side channel effects such as temporal disparity and intensity fluctuation of the photon pulses caused by random bit generation with multiple laser diodes in high-speed polarization-based BB84 quantum key distribution(QKD) systems can be eliminated by increasing the DC bias current condition. However, background photons caused by the spontaneous emission process under high DC bias current degrade the performance of QKD systems. In this study, we investigated the effects of spontaneously emitted photons on the system performance in a high-speed QKD system at a clock rate of 400 MHz. Also, we show further improvements in the system performance without side channel effects by utilizing the temporal filtering technique with real-time fieldprogrammable gate array signal processing.

Investigation of magnetization reversal process in pinned CoFeB thin film by in-situ Lorentz TEM

Exchange bias effect has been widely employed for various magnetic devices.The experimentally reported magnitude of exchange bias field is often smaller than that predicted theoretically,which is considered to be due to the partly pinned spins of ferromagnetic layer by antiferromagnetic layer.However,mapping the distribution of pinned spins is challenging.In this work,we directly image the reverse domain nucleation and domain wall movement process in the exchange biased Co Fe B/Ir Mn bilayers by Lorentz transmission electron microscopy.From the in-situ experiments,we obtain the distribution mapping of the pinning strength,showing that only 1/6 of the ferromagnetic layer at the interface is strongly pinned by the antiferromagnetic layer.Our results prove the existence of an inhomogeneous pinning effect in exchange bias systems.

Maintenance Management Research of a Large-span Continuous Rigid Frame Bridge Based on Reliability Assessment by Using Strain Monitored Data

When the bridge components needing maintenance are the world problem at present,and the health monitoring system is considered to be a very help­ful tool for solving this problem.In this paper,a large number of strain data acquired from the structural health monitoring system(SHMS)installed on a continuous rigid frame bridge are adopted to do reliability assessment.Firstly,a calculation method of punctiform time-dependent reliability is proposed based on the basic reliability theory,and introduced how to cal­culate reliability of the bridge by using the stress data transformed from the strain data.Secondly,combined with“Three Sigma”principle and the basic pressure safety reserve requirement,the critical load effects distribu­tion function of the bridge is defined,and then the maintenance reliability threshold for controlling the unfavorable load state which appears in the early operation stage of this type bridge is suggested,and then the combi­nation of bridge maintenance management and health monitoring system is realized.Finally,the transformed stress distribution certifies that the load effects of concrete bridges practically have a normal distribution;as for the concrete continuous rigid frame bridge with C50 strength grade concrete,the retrofit reliability threshold should be valued at 6.13.The methodology suggested in this article can help bridge engineers do effective maintenance of bridges,which can effectively extend the service life of the bridge and bring better economic and social benefits.

Preparation of Heavily Te-doped GaSb Single Crystal

Based on comparison of the single crystal growth from several Czochralski techniques,it showed that the most advantageous method for GaSb growth seems to be LEC pulling method.Highly Te doped GaSb single crystals can be prepared on small scale with good reproducibility by using special filtering technology.Using the Te concentrations calculated from the Hall measurement,the distribution coefficient of tellurium in GaSb was estimated to be about 0.38 under our growth conditions.The etch pit density (EPD) examination in <100> GaSb showed that the profile of EPD is of W shape in growth plane and the value of average EPD is about 1.0×10 -3 cm -2 along growth direction.

Definition and expression of non-symmetric physical properties in space for uniaxial crystals

The anisotropic physical property is the most noteworthy feature of crystals.In this paper,the subscript change method is used to analyze the sign changes of different tensors describing physical properties in uniaxial crystals.The distribution of some physical properties in special point groups exhibits non-symmetry in eight quadrants,which should attract the attention of crystal research.The difference between the crystallographic and physical coordinate systems and the lack of crystal symmetry operations are considered to be the origins of the non-symmetry.To avoid ambiguities and difficulties in characterizing and applying crystal physical properties,eight quadrants in space should be clarified.Hence,we proposed the use of piezoelectric properties to define the positive direction of the optical coordinate axis prior to the research and applications of optical properties.

WIND SPEED DISTRIBUTION REGULARITY AND WIND REDUCTION EFFECT OF SHELTER NET

Wind speed distribution regularities in a shelter mesh (S. M.) have been deduced from the wind speed distribution in the sheltered area of a single shelter beh (S. B.).The components of a wind vector in a mesh follow the error function distribution model or the logarithmic model of 2-variable power function.The wind vector itself follows the vector composition model of these models.We can calculate the wind speed distribution and wind reduction effect of a mesh under the conditions of any shelter-belt characteristics, any size and shape of a mesh and any wind inclination angle with this model. The results of our field model experiment are in better agreement with the theoretically calculated results.

Effect of standing-wave field distribution on femosecond laser-induced damage of HfO_2/SiO_2 mirror coating

Single-pulse and multi-pulse damage behaviors of ＂standard＂ （with A/4 stack structure） and ＂modified＂ （with reduced standing-wave field） HfO2/SiO2 mirror coatings are investigated using a commercial 50-fs, 800-nm Ti：sapphire laser system. Precise morphologies of damaged sites display strikingly different features when the samples are subjected to various number of incident pulses, which are explained reasonably by the standing-wave field distribution within the coatings. Meanwhile, the single-pulse laser-induced damage threshold of the ＂standard＂ mirror is improved by about 14% while suppressing the normalized electric field intensity at the outmost interface of the HfO2 and SiO2 layers by 37%. To discuss the damage mechanism, a theoretical model based on photoionization, avalanche ionization, and decays of electrons is adopted to simulate the evolution curves of the conduction-band electron densitv during r^ulse dHratian.

Minimization of Stock Weight during Close-Die Forging of a Spindle

In this paper, Finite Element method and full-scale experiments have been used to study a hot forging method for fabrication of a spindle using reduced initial stock size. The forging sequence is carried out in two stages. In the first stage, the hot rolled cylindrical billet is pre-formed and pierced in a closed die using a spherical nosed punch to within 20 mm of its base. This process of piercing or impact extrusion leads to high strains within the work piece but requires high press loads. In the second stage, the resulting cylinder is placed in a die with a flange chamber and upset forged to form a flange. The stock mass is optimized for complete die filling. Process parameters such as effective strain distribution, material flow and forging load in different stages of the process are analyzed. It is concluded from the simulations that minor modifications of piercing punch geometry to reduce contact between the punch and emerging vertical walls of the cylinder appreciably reduces the piercing load. In the flange chamber, a die surfaces angle of 52° instead of 45° is proposed to ensure effective material flow and exert sufficient tool pressure to achieve complete cavity filling. In order to achieve better compression, it is also proposed to shorten both the length of the inserted punch and the die “tongues” by a few mm.