On the Construction of d-Continuous, Modules

In this paper we introduce and study the notion of dual Continuous (d-Continuous) modules,A decomposition theorem for a d-continuous modules is proved.this generalizes all known decomposition theorens for quasi-projective modules.

SL(3,p^n)(p≥7)的第一Cartan不变量

一般性地计算了ｐ≥７时李型有限群ＳＬ（３，ｐｎ）的第一Ｃａｒｔａｎ不变量Ｃ（ｎ）００以及射影不可分解模Ｕｎ（０）的维数ｄｉｍＵｎ（０）。

Strongly Ding projective modules with respect to a semidualizing module

This paper is a study of strongly Ding projective modules with respect to a semidualizing module. The class of strongly Ding flat modules with respect to a semidualizing module is also investigated, and the relationship between strongly Ding projective modules and strongly Ding flat modules with respect to a semidualizing module is characterized.Some well-known results on strongly Ding projective modules, n-strongly Ding projective modules and strongly D_C-projective modules are generalized and unified.

A Significant Look at the Effects of Persian Gulf Environmental Conditions on Sound Scattering Based on Small Perturbation Method

The main goal of this paper is to investigate sound scattering from the sea surface, by Kuo＇s small perturbation method （SPM）, in the Persian Gulf＇s environmental conditions. Accordingly the SPM method is reviewed, then it is demonstrated how it can accurately model sound scattering from the sea surface. Since in Kuo＇s approach, the effects of surface roughness and sub-surface bubble plumes on incident sounds can be studied separately, it is possible to investigate the importance of each mechanism in various scattering regimes. To conduct this study, wind and wave information reported by Arzanah station as well as some numerical atmospheric models for the Persian Gulf are presented and applied to examine sound scattering from the sea surface in the Persian Gulf region. Plots of scattering strength by Kuo＇s SPM method versus grazing angle for various frequencies, wave heights, and wind speeds are presented. The calculated scattering strength by the SPM method for various frequencies and wind speeds are compared against the results of critical sea tests 7 （CST-7）. The favorable agreement achieved for sound scattering in the Persian Gulf region is indicative of the fact that the SPM method can quite accurately model and predict sound scattering from the sea surface.

Lossless Digital Watermarking Scheme for Image Maps

A lossless digital watermarking scheme,which was zero- perturbation on the content and graphics for the digital image maps,is proposed.During the simulation,the scheme has been utilized to model the copyright protection program as a commerce application.Compared to the traditional digital watermarking schemes,our scheme operates in redundancy areas of maps and is scalable to topology changes.Experimental results show that,with respect to the geometric attacks and image transformed,the performance of our scheme is better than the classical algorithms based space or frequency domain with much lower complexity..

Accelerating Life Test Scheme and Modeling Method for Machinegun

There is a pressing need for improving the current whole life shooting method in order to reduce ammunition consumption in the firearms lifetime test. The influencing factors, the characterization parameters and the correlation analysis result of lifetime were considered. Accelerating life test and measuring scheme for machinegun were designed systematically by applying such theoretical methods as accelerating test, uniform design and lifetime model. As result, it provides a more scientific and reasonable accelerating life test scheme and proposes methods on modeling lifetime, optimizing model and characterizing lifetime. The conclusion can be used in preparing accelerating life test scheme and lifetime model for machinegun.

A Note on Perfect Rings

对于交换环R,Chase[1]证明:对任意集A,若R^A是射影模,则R是一个Artin环.而对非交换环,有例子说明,此结论不成立.本文讨论了对什么环,当R是射影模时,R是一个Artin环.

Gorenstein projective modules and Frobenius extensions

We prove that for a Frobenius extension, if a module over the extension ring is Gorenstein projective,then its underlying module over the base ring is Gorenstein projective; the converse holds if the frobenius extension is either left-Gorenstein or separable(e.g., the integral group ring extension ZZG).Moreover, for the Frobenius extension RA = R[x]/(x^2), we show that: a graded A-module is Gorenstein projective in GrMod(A), if and only if its ungraded A-module is Gorenstein projective, if and only if its underlying R-module is Gorenstein projective. It immediately follows that an R-complex is Gorenstein projective if and only if all its items are Gorenstein projective R-modules.

Modeling of Thermal Properties of Thermal Insulation Layered with Transparent,Opaque and Reflective Film

The popular and effective food preservation technology based on refrigeration is not sufficient for high-quality products while undergoing logistic operations(transport and retail). One of the basic factors that affects the quality of chilled and frozen food products during storage and transport is packaging. A protective function of packaging strongly depends on the material used and its composition. There are different kinds of thermal insulation used for food packaging. One of them, proposed by the authors is a multilayer structure of insulation made of rectangular air cells. The insulation can be prepared by means of plastic film featuring various properties. The paper presents how to improve an effective material designed for food freezing and transport aiming to enhance its thermal resistance through the application of different transparency, reflectivity and emissivity of the film. Mathematical model based on heat exchange equations, including conduction, convection and radiation throughout a number of parallel internal sheets of film of multilayer structures was proposed. Thermal properties depending on different transparency, reflectivity and emissivity of the film were analyzed. The model was verified experimentally showing its compatibility and obtaining a significant influence of thermal resistance according to the type of film used to make air structures, the number and thickness of its layers as well as the gaps between internal folds. For multi-layer insulation designed for the insulation of packed frozen food in the shape of a rectangle, it was recommended to apply film transmittance as small as possible for the internal parts of the structure.

Morphism Categories of Gorenstein-projective Modules

Let A be an algebra of finite Cohen-Macaulay type and F its Cohen-Macaulay Auslander algebra. We are going to characterize the morphism category Mor（∧-Gproj） of Gorenstein-projective ∧-modules in terms of the module category F-mod by a categorical equivalence. Based on this, we obtain that some factor category of the epimorphism category Epi（∧-Gproj） is a Frobenius category, and also, we clarify the relations among Mor（∧-Gproj）, Mor（T2（∧）-Gproj） and Mor（△-Gproj）, where T2（∧） and △ are respectively the lower triangular matrix algebra and the Morita ring closely related to ∧.

The numerical simulation of caesium-137 transportation in oceanand the assessment of its radioactive impacts after Fukushima NPP release

After the damage of Fukushima Daiichi Nuclear Power Plant, a great number of radioactive materials were released into the Pacific Ocean. Therefore, it is necessary to research on the temporal and spatial distribution of these radionuclides. We use Princeton Ocean Model to simulate the circulation of the coast water of Fukushima NPP and obtain the concentration of caesium-137 by solving the diffusion equations. We employ the Monte Carlo N-particle(MCNP) code to assess the external doses caused by these contaminated sea water. To improve the efficiency and effectiveness of volume source in MCNP code, we establish a transformation method between spot source and volume source, and determine an appropriate range of volume source. Finally, we calculate the absorbed doses of every organ/tissue and the effective dose of a human body.

Hypergeometric equations and weighted projective spaces

We compute the Hodge numbers of the polarised(pure) variation of Hodge structure V = grn-1WRn-1f!Z of the Landau-Ginzburg model f:Y → C mirror-dual to a weighted projective space wPn in terms of a variant of Reid's age function of the anticanonical cone over wPn.This implies,for instance,that wPn has canonical singularities if and only if hn-1,0V = 1.We state a conjectural formula for the Hodge numbers of general hypergeometric variations.We show that a general fibre of the Landau-Ginzburg model is birational to a Calabi-Yau variety if and only if a general anticanonical section of wP is Calabi-Yau.We analyse the 104 weighted 3-spaces with canonical singularities,and show that a general anticanonical section is not a K3 surface exactly in those 9 cases where a generic fibre of the Landau-Ginzburg model is an elliptic surface of Kodaira dimension 1.