保护藏书容易忽视的一个问题

图书的分类排架,优点大于缺点,为一般图书馆所采用,但有一个如何妥善处理图书开本大小不一的问题。我国一般用787×1092毫米纸,以这种纸型印刷的图书开本(见表一)可分为: 微型开本——书脊高度小于180毫米,即小于一般32开本的书籍;

21世纪:澳门之“门”往哪开?

国际微型都市——澳门就要回家了,回归后,中国社会主义“一国两制”管辖的资本主义澳门将何去何从?据统计:澳门,1997年自身常驻人口只有41.4128万人,而1997全年,来自世界各地的入境旅客竟高达500万人次以上,最高年份的入境旅客超过800万人次。一个以旅游、娱乐博彩为主业的澳门,一个袖珍、高度参与国际交换的都市。

Impacts of salinity parameterizations on temperature simulation over and in a hypersaline lake

In this paper,we introduced parameterizations of the salinity effects(on heat capacity,thermal conductivity,freezing point and saturated vapor pressure) in a lake scheme integrated in the Weather Research and Forecasting model coupled with the Community Land Model(WRF-CLM). This was done to improve temperature simulation over and in a saline lake and to test the contributions of salinity effects on various water properties via sensitivity experiments. The modified lake scheme consists of the lake module in the CLM model,which is the land component of the WRF-CLM model. The Great Salt Lake(GSL) in the USA was selected as the study area. The simulation was performed from September 3,2001 to September 30,2002. Our results show that the modif ied WRF-CLM model that includes the lake scheme considering salinity effects can reasonably simulate temperature over and in the GSL. This model had much greater accuracy than neglecting salinity effects,particularly in a very cold event when that effect alters the freezing point. The salinity effect on saturated vapor pressure can reduce latent heat flux over the lake and make it slightly warmer. The salinity effect on heat capacity can also make lake temperature prone to changes. However,the salinity effect on thermal conductivity was found insignificant in our simulations.

Adaptive neural network based sliding mode altitude control for a quadrotor UAV

Reasons and realities such as being non-linear of dynamical equations,being lightweight and unstable nature of quadrotor,along with internal and external disturbances and parametric uncertainties,have caused that the controller design for these quadrotors is considered the challenging issue of the day.In this work,an adaptive sliding mode controller based on neural network is proposed to control the altitude of a quadrotor.The error and error derivative of the altitude of a quadrotor are the inputs of neural network and altitude sliding surface variable is its output.Neural network estimates the sliding surface variable adaptively according to the conditions of quadrotor and sets the altitude of a quadrotor equal to the desired value.The proposed controller stability has been proven by Lyapunov theory and it is shown that all system states reach to sliding surface and are remaining in it.The superiority of the proposed control method has been proven by comparison and simulation results.

Peak Profile Analysis in High Field Asymmetric Wave Ion Mobility Spectrometry

High field asymmetric wave ion mobility spectrometry （FAIMS） is a powerful tool to detect and characterize gas-phase ions, while the unsolvable partial differential equation of ions moving in ion drift tube poses a big challenge to FAIMS spectral peak analysis. In this work, a universal and effective model of FAIMS spectral peak profile has been proposed by introducing ion trajectory and loss height. With this model, the influence of the structure of ion drift tube, dispersion voltages, compensation voltages, and carrier gas flow rate on the FAIMS spectral peak characteristics like peak shape, full width at half maximum and peak height is analyzed and discussed. The results show that the influence of different factors on the FAIMS spectral peak profile can be qualitatively described by the model which agrees with the experimental data.

A novel low-voltage high precision current reference based on subthreshold MOSFETs

A novel topology low-voltage high precision current reference based on subthreshold Metal-Oxide-Semiconductor Field Effect Transistors （MOSFETs） is presented. The circuit achieves a temperature-independent reference current by a proper combination current of two first-order temperature-compensation current references, which exploit the temperature characteristics of integrated poly2 resistors and the 1- V transconductance characteristics of MOSFET operating in the subthreshold region. The circuit, designed with the 1 st silicon 0.35 μm standard CMOS logic process technology, exhibits a stable current of about 2.25 μA with much low temperature coefficient of 3 × 10^-4μA/℃ in the temperature range of-40-150 ℃ at 1 V supply voltage, and also achieves a better power supply rejection ratio （PSRR） over a broad frequency. The PSRR is about -78 dB at DC and remains -42 dB at the frequency higher than 10 MHz. The maximal process error is about 6,7% based on the Monte Carlo simulation. So it has good process compatibility.

Morphological parameters of both surfaces of coupled joint

Twenty one joints were made with Brazilian tests and each surface was scanned by the Talysurf CLI 2000. Morphological characteristics of joint surface were quantified by statistical and textural parameters. By the contrast of these parameters between both sides of each coupled joint, the following conclusions are drawn. The upper and lower surfaces of coupled joints have approximately equal values of Sp（maximum height of joint surface）, Sa（arithmetic mean height of joint surface） and Sq（root mean square height of joint surface）, but the Ssk（skewness of the height distribution of joint surface） values of the two surfaces of a coupled joint are different, one is positive while the other is negative. The Saj（auto-correlation length） parameter values of both surfaces of each coupled joint are quite close, and the S^（texture aspect ratio） values have the same situation to the Sal parameter, but the same parameters of different surfaces have big differences which illustrates its own characteristics of each joint. The two surfaces of each coupled joint have similar values of θp （mean profile angle） which can be used to deduce the value of θp each other.

ZMP-based Gait Optimization of the Biped Robot

The gait of the biped robot is described using six parameters such as stature,velocity,length of the step,etc.The algorithm of the Newton-Euler is actualized by object-oriented idea,and then the zero moment point (ZMP) of the dynamically walking biped is calculated.Finally,the gait of biped is optimized using gene algorithm,and the optimized result prove the correctness of the algorithm.

Analysis on a Set of 12-parameter Rectangular Plate Element with High Accuracy

It is proved that the so-called a set of 12-parameter rectangular plate elements with high accuracy constructed by using double set parameter method and undetermined method are, in fact, the same one; the real shape function space is nothing but the Adini＇s element＇s, which has nothing to do with the other high degree terms and leads to a new method for constructing the high accuracy plate elements. This fact has never been seen for other conventional and unconventional, conforming and nonconforming rectangular plate elements, such as Quasi-conforming elements, generalized conforming elements and other double set parameter finite elements. Moreover, such kind of rectangular elements can not be constructed by the conventional finite element methods.

The Domino Effect

A row of dominoes which stand on edge will undergo a cascade when the first domino is tipped. First domino strokes the next and the wave of falling dominoes propagates. The purpose of this work is to investigate wave speed dependence on various domino parameters as the number of elements and the distance between dominoes and their dimensions. Theoretical examination of falling dominoes process is to create the mathematical model of the process and compare between the calculations and experimental results. An experiment with using of the speed camera was made. The dominoes of three different types of material were used. For theoretical investigation of the problem, the model [1] was used. The program for computer calculations was written. Time of a dominoes row falling was calculated without taking friction between neighbours. The calculation results show that the speed of falling dominoes reaches its constant value. This stable velocity depends on the geometric parameters of dominoes and the surface friction between dominoes but does not depend on the mass of dominoes.

Study of front bumper process on the basis of hot stamping

The fitting method is used for obtaining the constitutive relation of ultra-high strength steel in this paper. At the same time, the forming limit of material is researched under different de/brmation conditions. Through experiments, the paper obtains stress-strain curve under different deformation temperatures and strain rates. On the basis of experimental data, the constitutive relation model is established which can reflect the de- fomlation capacity of ultra-high strength steel during process of hot stamping. Combining with finite element simulation results of hot stamping by the commercial software AUTOFORM, transfer path of load and matching law of strength, the paper determines the design criteria and forming process requirements of parts manufactured by hot stamping. Through setting different process parameters, such as punch velocity and friction coefficient, and blank shape, the paper finds that process parameters and blank shape have an essential effect on the quality of parts.

Atomic force microscopy study on microstructure of various ranks of coals

As a new technology, Atomil Force Microscopy （AFM） is being used in the research of microscopic structure on coal surface in recent years. By this technology, we can observe the nanoscale pore and crack shape of coal surface, and measure some structural parameters. Different metamorphic grades produce different feature of surface microscopic structure of coal. This paper analyzes the surface microscopic structure of different metamorphic grade coal by AFM. The results show that the coal surface microstructure has a trend from rough to smooth with the increasing of metamorphic grade. The low rank coals contain large or medium pores and the high rank coals contain micro pores. The values of surface morphology characteristic parameters （Sq and Sa） nonlinearly decrease with the increasing coal rank. That is, the coal surface becomes smoother during coalification.

A topographic parameter inversion method based on laser altimetry

A topographic parameter inversion method based on laser altimetry is developed in this paper, which can be used to deduce the surface vertical profile and retrieve the topographic parameters within the laser footprints by analyzing and simulating return waveforms. This method comprises three steps. The first step is to build the numerical models for the whole measuring procedure of laser altimetry, construct digital elevation models for surfaces with different topographic parameters, and calculate return waveforms. The second step is to analyze the simulated return waveforms to obtain their characteristics parameters, summarize the effects of the topographic parameter variations on the characteristic parameters of simulated return waveforms, and analyze the observed return waveforms of laser altimeters to acquire their characteristic parameters at the same time. The last step is to match the characteristic parameters of the simulated and observed return waveforms, and deduce the topographic parameters within the laser footprint. This method can be used to retrieve the topographic parameters within the laser footprint from the observed return waveforms of spaceborne laser altimeters and to get knowledge about the surface altitude distribution within the laser footprint other than only getting the height of the surface encountered firstly by the laser beam, which extends laser altimeters' function and makes them more like radars.

nuclear reaction models and methods fusion reactions

The behaviors of barrier characteristics are analyzed for spherical-oblate systems over different configurations of colliding nuclei. For this purpose, we have extended our previous study [Phys. Rev. C 89（2014） 054607], it is devoted to optimum ＂cold＂ and ＂hot＂ configuration] to analyze the same reaction systems in various configurations.The investigation on some chosen systems reveals that the barrier height and its position can be parameterized in times of the different orientations.

A common origin of muon g-2 anomaly,Galaxy Center GeV excess and AMS-02 anti-proton excess in the NMSSM

The supersymmetric model is one of the most attractive extensions of the Standard Model of particle physics.In light of the most recently reported anomaly of the muon g-2 measurement by the FermiLab E989 experiment,and the excesses of gamma rays at the Galactic center observed by Fermi-LAT space telescope,as well as the antiproton excess observed by the Alpha Magnetic Spectrometer,we propose to account for all these anomalies or excesses in the Next-to-Minimal Supersymmetric Standard Model(NMSSM).Considering various experimental constraints including the Higgs mass,B-physics,collider data,dark matter relic density and direct detections,we find that a~60 GeV bino-like neutralino is able to successfully explain all these observations.Our scenario can be sensitively probed by future direct detection experiments.

Analysis and optimum design of rider-bicycle mechanisms:Design of bicycle parameters for a specified rider

Optimum design of rider-bicycle mechanisms is very important for customizing bicycles and plays a crucial role in the improvement of athletes' performances and in protection of the riders.Since the birth of the first bicycle,people have been keeping optimizing bicycles with respect to physical conditions of human.In modern design,the basic structure of a bicycle has been formulized,while many geographic parameters remain uncertain.In this paper,the bicycle and the human body are considered as a kinematic mechanism,called rider-bicycle mechanism.The optimum design is implemented from the perspective of mechanism.Effort-saving and comfortableness are considered at the same time.The corresponding performance charts are drawn and the relationship between the performances and parameters of seat height,crank length and body parameters are discussed.By using these charts,the optimal design method of bicycle's parameters for a specified person is then founded.Optimum solutions to get suitable seat height and crank length for a person are obtained accordingly.The research is of significance for customizing bicycles and design of bicycle robot.

What can we learn from the tension between PLANCK and BICEP2 data?

Recently BICEP2 collaboration has announced the detection of the primordial gravitational waves at high confidence level. In light of the results of B-modes power spectrum from BICEP2 and using the based ACDM, a constraint on the tensor-to-scalar ratio r = 0.20-0.05＋0.07 （68% C.L.） can be obtained, however, this result is in apparent tension with the limit on standard inflation models from the recent PLANCK measurement, r 〈 0.11 （95% C.L.）. Herein we review the recent progress on the cosmological studies after BICEP2 and discuss on different ways of reconciling the tension between PLANCK and BICEP2 data. We will discuss possible modifications on the standard cosmological model, such as including the running of scalar spectral index or other cosmological parameters correlated with inflationary cosmological parameters, or tilting the primordial power spectrum at large scales by introducing a cut off which can be predicted by bouncing cosmology. We will also comment on another possibility of generating extra B-modes of CMB polarization, namely by a non-zero polarization rotation angle during its transferring from the last scattering surface.

Gauss-Bonnet as Effective Cosmological Constant

It is known that Gauss-Bonnet terms in higher dimensional gravity can produce an effective cosmological constant.We add extra examples to this picture by presenting explicitly two branches of accelerating vacuum solutions to the Einstein-Gauss-Bonnet gravities with a bare cosmological constant in 5 and 6 dimensions.Both branches of solutions are of constant curvature and the effective cosmological constants are independent of the acceleration parameter.One branch(the "-" branch) of the solutions is well defined in the limit when the Gauss-Bonnet parameter approaches zero,in which case the effective cosmological constant becomes identical with the bare value,while the other(i.e.the "+") branch is singular in the same limit,and beyond this singular limit,the effective cosmological constant is inversely proportional to the Gauss-Bonnet parameter with a negative constant of proportionality when the bare value vanishes.

Interspecific comparison of the flight performance between sparrowhawks and common buzzards migrating at the Falsterbo peninsula： A radar study

In order to compare the two species＇ flight performance over the exposed and windy Falsterbo Peninsula, where thermal conditions seldomly are very favorable, we used tracking radar to study flight parameters of sparrowhawks Accipiter ni- sus and common buzzards Buteo buteo during autumn migration. The results showed a clear difference between sparrowhawks and common buzzards in their flight altitudes and speeds, and in the wind conditions they encountered. Common buzzards had higher flight altitudes and were more selective of wind. Flight altitude was negatively related to the wind speed, which was most pronounced for common buzzards. Sparrowhawks had higher mean air- and cross-country speeds than common buzzards. Air- speed was negatively related, whereas ground and cross-country speeds were positively related to the tailwind component for both raptors. The differences between sparrowhawks and buzzards could to a large degree be explained by a larger dependence on thermal soaring among the common buzzards; a strategy associated with selectivity for favourable thermal and wind conditions during migratory flight. An additional important explanation for the interspecific differences was the habit of the sparrowhawks to combine migratory flight with hunting for prey, which makes it prone to fly at lower altitudes and use flapping flight to a much larger degree than common buzzards which do not forage during their migratory passage of the Falsterbo Peninsula [Current Zoo- logy 60（5）： 670-679, 2014].

Parameters optimization of π-phase-shifted long-period fiber grating for gas sensing

The gas-sensitive film coated π-phase-shifted long-period fiber grating(LPFG),consisting of two same long-period fiber gratings cascaded by a regular fiber with length of half of the grating period,is proposed for gas sensing.The sensitivity of the sensor is defined by the change rate of the transmission at specific wavelength with respect to the film refractive index.The qualitative and numerical analyses show that to get a high sensitivity,the optimal coupling strength of each long-period fiber grating is √2 π/4.With this coupling strength,the longer the grating is,the higher sensitivity the sensor has.By choosing appropriate grating period,a high sensitivity for the film with a certain refractive index and thickness can be attained.