Cross section measurements of scale-model tactical targets by using 0.1 THz compact radar system

We present a new compact radar system to measure a terahertz radar cross section(RCS) of metal plates,trihedral corner reflectors,and an aircraft scaled model with a 0.1 THz continuous wave.We both numerically and experimentally investigate the terahertz RCS of the metal plates and trihedral corner reflectors.The numerical simulations are obtained by using commercial software,i.e.,computer simulation technology,which agree well with the experimental results.Then,the RCS of an aircraft scaled model is measured,and the experimental results are in good agreement with the physical characteristics of the scaled model.The effectiveness of our compact radar system is verified to get the RCS of complex targets,such as the scaled models of the tactical targets.

Sectional Dimensions Identification of Metal Profile by Image Processing

In steel plants, estimation of the production system characteristic is highly critical to adjust the system parameters for best efficiency. Although the system parameters may be tuned very well, due to the machine and human factors involved in the production line some deficiencies may occur in product. It is important to detect such problems as early as possible. Surface defects and dimensional deviations are the most important quality problems. In this study, it is aimed to develop an approach to measure the dimensions of metal profiles by obtaining images of them. This will be of use in detecting the deviations in dimensions. A platform was introduced to simulate the real-time environment and images were taken from the metal profile using 4 laser light sources. The shape of the material is generated by combining the images taken from different cameras. Real dimensions were obtained by using image processing and mathematical conversion operations on the images. The results obtained with small deviations from the real values showed that this method can be applied in a real-time production line.

Erratum to “Absolute Measurement of Cross Sections of ^(27)Al(n,α)^(24)Na and ^(56)Fe(n,p)^(56)Mn Reactions at E_n=14.6 MeV”

The publisher regrets that some misprints appeared in the formula for the correction factork on page 343.It is reprinted correctly as the following:k=n(1-e-λ（t1-t0）/n)/eλ（t1-t0）-1·(sum from i=1 to n Naieiλ（l1-l0）/n)/sum from i=1 to n Nai

RESEARCH ON THE ON-LINE MEASURING SYSTEM FOR THE MIDDLE-CONVEX AND VARYING ELLIPSE PISTON SKIRT

The middle convex and varying ellipse piston is th e key component of an internal combustion engine In general,the piston is mac hined by non circular section CNC lathe,but the measuring of piston profile is manipulated by off line Because the off line measuring reference is differen t from the machining reference,the measurement result is diverse from the act ual dimension A new method to measure the middle convex and varying ellipse p iston profile, which is known as on line measuring, is presented By using thi s kind of method,the high measurement accuracy can be gained,as well as meeting the production requirement.

Observation of e^(+)e^(-)→pppñπ-+c.c.

Using data taken at 29 center-of-mass energies between 4.16 and 4.70 GeV with the BESⅢdetector at the Beijing Electron Positron Collider corresponding to a total integrated luminosity of approximately 18.8 fb^(-1),the process e^(+)e^(-)→pppñπ+c.c.is observed for the first time with a statistical significance of 11.5σ.The average Born cross sections in the energy ranges of(4.160,4.380)GeV,(4.400,4.600)GeV and(4.610,4.700)GeV are measured to be(21.5±5.7±1.2)fb,(46.3±10.6±2.5)fb and(59.0±9.4±3.2)fb,respectively,where the first uncertainties are statistical and the second are systematic.The line shapes of the pñ and ppπ^(-)invariant mass spectra are consistent with phase space distributions,indicating that no hexaquark or di-baryon state is observed.