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Three experiments were conducted to determine the optimal dietary standardized ileal digestible (SID) Trp to Lys ratio (Trp:Lys) for grower-finisher pigs with body weight of 20–50 (Experiment (Exp.) 1), 50–80 (Exp. 2), and 80–110 kg (Exp. 3). A total of 4032 Duroc × Yorkshire × Landrace barrows and gilts were used in the experiments with a randomized complete blocked design. For each experiment, 1344 pigs were randomly assigned into 6 dietary treatments (SID Trp:Lys levels: 0.150, 0.165, 0.180, 0.195, 0.210, and 0.225) with 8 replicate pens per treatment (14 barrows and 14 gilts per pen). Synthetic Trp was used to adjust the dietary SID Trp:Lys, while the Lys content in all 6 diets remained fixed in each experiment. In Exp. 1, the average daily gain (ADG), average daily feed intake (ADFI), gain to feed ratio (G:F), and serum urea N (SUN) were increased quadratically (P

Earth satellites have observed continuous increasing vegetation growth during the past four decades, a phenomenon called Earth greening. Nearly all Earth System Models (ESMs) participated in Coupled Model Intercomparison Project (CMIP) for Intergovernmental Panel on Climate Change (IPCC) project a continuous greening of the planet during the 21st century. To investigate the hydrological feedback from projected Earth greening, we prescribed the increase in leaf area index (LAI) in the 21st century as projected by CMIP5 ESMs into a state-of-the-art ESM (IPSLCM), and simulated equilibrium climates for current CO2 and LAI, an increase of CO2 alone, an increase of LAI alone, and increases of both CO2 and LAI, respectively. We find that the greening simultaneously intensifies evapotranspiration and precipitation over land. In terms of soil moisture content, the spatial difference between the responses of evapotranspiration and precipitation causes a hydrological response of the "dry gets drier, wet gets wetter" (DDWW) paradigm. Increasing LAI significantly decreases soil moisture content over dry regions, including Western North America, Southern South America, East Siberia, Central Asia, South Asia, Northern China, Sahel, Southern Africa and Australia. Over wet regions particularly Amazon and Congo rainforests, the greening-induced increase of terrestrial evapotranspiration favors more convective precipitation, so that the new equilibrium does not decrease soil moisture content. The DDWW paradigm in terms of P-ET response does not hold over wet areas. To mitigate climate with forestry, policymakers should prevent degradation of existing forests, support afforestation over wet regions, and avoid planting trees in dry regions.

With the increasing penetration of distributed renewable resources (RES) and flexible loads, distribution networks are gradually developing into an active distribution network (ADN), which includes many microgrids (MGs). By considering the network structure, operational targets, and transactional relationship of the ADN, this paper proposes a “physical-transactional” scheme to promote RES consumption through specifically designed price mechanisms. The proposed price forming mechanisms consider the traditional transactions and incorporate the supply-demand ratio into the dynamic price forming process to better suit the highly penetrated renewable energy and small-scale local markets. Through this framework, each player can maximize his/her interest, such as system security, social welfare, the satisfaction of electricity consumption, etc., while renewable energy consumption and sharing can be maximumly promoted. The exponential penalty function-based decomposition and Lyapunov theory-based solution for the multilayer optimization model are employed to solve the inter-layer coordination and individual optimization simultaneously. Finally, a modified IEEE-69 system is taken as an example to verify that the proposed method. Our simulation shows that the proposed framework can promote renewable energy consumption and sharing and improve the social welfare of the ADN.

In this work, the effect of plastic deformation-induced martensite on the CE behavior of 304 SS was investigated by micro-area XRD, nano indentation and EBSD. Results indicated that the martensitic content initially displayed an increased trend and then decreased in the later stage. The formation of martensite was beneficial to the CE resistance of 304 SS in incubation and rising periods since the impact energy dissipation through martensitic transformation and the strengthening effect of martensite were dominant. However, it was no longer conductive to the CE resistance in stable period in virtue of the severely damaged surface and the markedly reduced plastic deformation ability. In addition, obvious grain refinement was observed in the CE surface layer, which should be correlated with the deformation twins cutting the original grains.

In order to establish the constitutive model to predict deformation behavior during quenching process, uniaxial tension behaviors of an as-quenched AA2219 sheet were investigated over a wide temperature range (298-773K) at different strain rates (0.001-1s-1) in quasi-static regime. The experimental results show that the flow stress is closely related to temperature and strain rate. The material exhibits negative strain rate sensitivity (SRS) that the flow stress decreases with increase of strain rate below a critical temperature of Tc. A model established by Kabirian et al. (Kabirian, F., Khan, A.S., Pandey, A. Int. J. Plast. 2014, 55) based on the KHL model considering the negative to positive SRS shows successful prediction of the flow stress in a temperature range of 296-473K. However, at higher temperatures (473-773K) the measured SRS deviates from the calculated values of Sigmoidal function given by Kabirianet al. with the increase of temperature. Therefore, in this paper, based on an extended Sigmoidal function and a proposed relation between flow stress and the coupling effects of strain and temperature, a modified Johnson-Cook model is proposed to describe the quasi-static stress-strain responses over a wider temperature range. Correlations using the modified model show good agreement with the experimental results.

Aluminum alloy thin sheets are widely used to produce light-weight high-strength components and the sheets are generally quenched before forming (Q-F) to improve the final mechanical properties of components. However, the distortion in quenching will significantly affect the quality and stability of the following forming process. In this study, the distortion behavior of 2219 aluminum alloy thin sheets and its forming mechanism in quenching process were investigated through experiments and finite element analysis (FEA). The results indicate that, the quenched thin sheets basically present three distortion modes, namely saddle-shape, shovel-shape and arch-shape. The distortion modes of the quenched thin sheets are determined by the bending modes of distortion zone which is the zone of the thin sheet near the water surface. When the bending mode is one-half sine wave, the quenching thin sheets always show saddle-shape. However, for the cases where the bending mode changes to three-half sine wave and the bending of distortion zone is suppressed, the quenching thin sheets show shovel-shaped and arch-shaped distortion modes, respectively. The reasons behind the variations of the bending mode are finally analyzed based on a buckling criterion under laterally constrained conditions. These results will provide an in-depth understanding of quenching distortion behavior and lay a basic guidance for controlling the distortion of thin sheets in quenching process.

In order to investigate the mechanism of thickness debit effect at different stress levels, creep tests of thin-walled Ni-based superalloys were conducted under three test conditions: 220 MPa, 275 MPa and 330 MPa at 980 °C. Results showed that the creep life reduced with the decrease of specimen thickness at 220 MPa and 275 MPa. At 330 MPa, this variation tendency was not so evident. Metallographic observations revealed that the specimen thickness and the external stress level affected the depth of γ' depleted region and the distribution of voids and cracks of the specimen. Thus, a phase-field model and a crack growth model were used to consider the influence of γ' depleted region and crack growth on life, respectively. It was found from the phase-field model that the existence of γ' depleted region led to more considerable plastic strain and equivalent stress in the normal γ/γ' phase region than that in the γ' depleted region. This phenomenon was more evident in the thin specimen at low stress level. At high stress level, the redistribution of the stress field was not so distinct due to the premature plastic deformation in the normal γ/γ' phase region. The crack growth models showed a shorter critical value of the crack length and faster crack propagation in the thin specimen. However, the increased external stress levels would decrease the disparity of cracks propagation between the thin and thick samples. Comprehensive consideration of the phase-field method and the crack growth model revealed the thickness debit effect at different stress levels.

ITER will be used to test tritium breeding module concepts, which will lead to the design of DEMO fusion reactor demonstrating tritium self-sufficiency and the extraction of high grade heat for electricity production. China plans to test the HCCB TBM modules during different operation phases. Related design and R&D activities for each TBM module with the auxiliary system are introduced. The helium-cooled ceramic breeder (HCCB) test blanket module (TBM) is the primary option of the Chinese TBM program. The preliminary conceptual design of CN HCCB TBM has been completed. A modified design to reduce the RAFM material mass to 1.3 ton has been carried out based on the ITER technical requirement. Basic characteristics and main design parameters of CN HCCB TBM are introduced briefly. The mock-up fabrication and component tests for Chinese test blanket module are being developed. Recent status of the components of CN HCCB TBM and fabrication technology development are also reported. The neutron multiplier Be pebbles, tritium breeder Li 4 SiO 4 pebbles, and structure material CLF-1 of ton-class are being prepared in laboratory scale. The fabrication of pebble bed container and experiment of tritium breeder pebble bed will be started soon. The fabrication technology development is proceeding as the large-scale mock-up fabrication enters into the R&D stage and demonstration tests toward TBM testing on ITER test port are being done as scheduled.

Upland cotton (Gossypium hirsutum L.) is an important cash crop that provides renewable natural fiber worldwide. Currently limited genetic base leads to a decrease in upland cotton genetic diversity. Multi-parent advance generation inter-cross (MAGIC) populations can be used to evaluate complex agronomic traits in crops. In this study, we developed an upland cotton MAGIC population. A total of 258 MAGIC population lines and their twelve founder lines were analyzed, using 432 pairs of simple sequence repeat (SSR) markers. Gene diversity indices and the polymorphism information content were calculated using polymorphism analyses. Our genotype analysis showed that 258 inbred lines could be divided into 158 genotypes. Among these, we identified 17 pairs of specific SSR primers on the A chromosome subgroups and 24 pairs of specific SSR primers on the B chromosome subgroups of upland cotton. These were related to 77 and 128 genotypes, respectively. Our results suggest that the upland cotton MAGIC population contained abundant genetic diversity and may provide enormous resources for future genetic breeding.

The helium-cooled ceramic breeder (HCCB) test blanket module (TBM) is the primary option of the Chinese TBM program. Current progress on the design and R&D for Chinese helium-cooled ceramic breeder TBM (CN HCCB TBM) in China is presented. The main updated design and related R&D of CN HCCB TBM are introduced briefly. The mock-up fabrication and component tests for Chinese test blanket module are being carried out. Recent status of the components and fabrication technology development is also reported. The neutron multiplier Be pebbles, tritium breeder Li4SiO4 pebbles, and structure material CFL-1 are being prepared in the laboratory scale. The fabrication of 1/3 sized mock-up and construction of a He test loop are being carried out. The key technology development is proceeding to the large scale mock-up fabrication and demonstration tests toward on ITER testing.

In order to avoid the limitations of traditional mechanism modeling method, a neural network (NN) model of variable - pitch wind turbine is built by the NN modeling method based on field data. Then considering that from wind turbine’s startup to grid integration, the generator speed must be controlled to rise to the synchronous speed smoothly and precisely, a neural network model predictive control (NNMPC) strategy based on the small-world optimization algorithm (SWOA) is proposed. Simulation results show that the strategy can forecast the change of generator rotational speed based on the wind speed disturbance, making the controller act ahead to eliminate the impact of system delay. Furthermore, the system output can track the reference trajectory well, making sure that the system can connect the electricity grid steadily.

The shape evolution and shape coexistence phenomena in neutron-rich nuclei at N ≈ 60 , including Kr, Sr, Zr, and Mo isotopes, are studied in the covariant density functional theory (DFT) with the new parameter set PC-PK1. Pairing correlations are treated using the BCS approximation with a separable pairing force. Sharp rising in the charge radii of Sr and Zr isotopes at N = 60 is observed and shown to be related to the rapid changing in nuclear shapes. The shape evolution is moderate in neighboring Kr and Mo isotopes. Similar as the results of previous Hartree–Fock–Bogoliubov (HFB) calculations with the Gogny force, triaxiality is observed in Mo isotopes and shown to be essential to reproduce quantitatively the corresponding charge radii. In addition, the coexistence of prolate and oblate shapes is found in both Sr 98 and Zr 100 . The observed oblate and prolate minima are related to the low single-particle energy level density around the Fermi surfaces of neutron and proton respectively. Furthermore, the 5-dimensional (5D) collective Hamiltonian determined by the calculations of the PC-PK1 energy functional is solved for Sr 98 and Zr 100 . The resultant excitation energy of 0 2 + state and E0 transition strength ρ 2 ( E 0 ; 0 2 + → 0 1 + ) are in rather good agreement with the data. It is found that the lower barrier height separating the two competing minima along the γ deformation in Zr 100 gives rise to the larger ρ 2 ( E 0 ; 0 2 + → 0 1 + ) than that in Sr 98 .

This paper presents a numerical simulation of damage evolution in multi-pass wire drawing process and its potential relevance to manufacturing design. The Gurson–Tvergaard–Needleman model (GTN model) is introduced to describe damage evolution in the drawn wire. Based on a three-dimensional model of the drawn wire generated through ABAQUS, the numerical analyses on damage behavior in multi-pass wire drawing are undertaken for the purpose of investigating the damage evolution during all phases of the process. Convergence problems in the process of simulation are discussed. The results illustrate the damage evolution of the drawn wire in each of the eight passes and the damage distribution along axial and circular directions. It turns out that the damage values continuously rise up with the increase of drawing passes and the damage evolution in the drawing process shows obvious nonlinear characteristic. The damage distribution along axial and circular directions agrees well with actual drawing situation. Wire breakage is expected to occur in those areas of the drawn wire where fractures most possibly initiate. Furthermore, the numerical analyses contribute a new approach for the optimization of the drawing parameters. Based on the principle of least damage accumulation in the drawing process, the optimal area reduction is chosen and selection of material processes is proposed. The currently standard 8-pass wire drawing process can be potentially optimized by a proposed 7-pass wire drawing process.

Current progress on the design and R&D of Chinese helium-cooled solid breeder test blanket module, CN HCSB TBM is presented. The updated design on structural, neutronics, thermal-hydraulics and safety analysis has been completed. In order to accommodate the HCSB TBM ancillary system, the design and necessary R&Ds corresponding sub-systems have being developed. Current status on the development of function materials, structure material and the helium test loop are also presented. The Chinese low-activation ferritic/martensitic steels CLF-1, which is the structural material for the HCSB TBM is being manufactured by industry. The neutron multiplier Be and tritium breeder Li4SiO4 pebbles are being prepared in laboratory scale.

The smooth ultra-nanocrystalline diamond (UNCD) films were prepared by microwave plasma chemical vapor deposition (MWCVD) using argon-rich CH 4 /H 2 /Ar plasmas with varying argon concentration from 96% to 98% and negative bias voltage from 0 to −150 V. The influences of argon concentration and negative bias voltage on the microstructure, morphology and phase composition of the deposited UNCD films are investigated by using scanning electron microscopy (SEM), X-ray diffraction (XRD), atom force microscopy (AFM), and visible and UV Raman spectroscopy. It was found that the introduction of argon in the plasma caused the grain size and surface roughness decrease. The RMS surface roughness of 9.6 nm (10 micron square area) and grain size of about 5.7 nm of smooth UNCD films were achieved on Si(100) substrate. Detailed experimental results and mechanisms for UNCD film deposition in argon-based plasma are discussed. The deposited highly smooth UNCD film is also expected to be applicable in medical implants, surface acoustic wave (SAW) devices and micro-electromechanical systems (MEMS).

The hot working characteristics of delta phase in the delta-processed Inconel 718 alloy during isothermal compression deformation attemperature of 950 degrees C and strain rate of 0.005 s(-1), were studied by using optical microscope, scanning electron microscope and quantitative X-ray diffraction technique. The results showed that the dissolution of plate-like delta phase and the precipitation of spherical 8 phase particles coexisted during the deformation, and the content of delta phase decreased from 7.05 wt.% to 5.14 wt.%. As a result of deformation breakage and dissolution breakage, the plate-like delta phase was spheroidized and transferred to spherical delta phase particles. In the center with largest strain, the plate-like delta phase disappeared and spherical delta phase appeared in the interior of grains and grain boundaries. (C) 2009 Elsevier Inc. All rights reserved.

Two actively cooled mock-ups with 2 mm thick tungsten armor joined to chromium copper alloy by explosive welding were developed, tested and analyzed in ASIPP of China. The heat load limit of the mock-up is 7 MW/m 2 , and delamination was observed along the W/Cu interface. The mock-ups can withstand the maximum heat flux of 6 MW/m 2 . SEM investigations showed that some cracks and failures appeared in filler materials and at copper/filler interface, but intactness was found at tungsten/filler interface. Numerical simulations indicated that if the distance decreases between the vertex of channel and the interface, the mock-up had the better structure reliability due to the reduction of temperature and stress. Under 4 MW/m 2 heat flux, the mock-up showed good heat transfer capabilities and high joint reliabilities. All these results demonstrate the explosive joining is also an alternative way to realize the W/Cu joint for the plasma facing components.

The beneficial effects of boron addition on microstructure transformations and mechanical properties of γ-TiAl alloys were investigated. Two growth mechanisms of boride (TiB2) in γ-TiAl alloy were confirmed, the curved flaky borides are products of irregular eutectic reaction growing coupled with matrix, while some faceted blocky borides in boron-rich alloy are primary TiB2 phase growing directly in melt. The core of flaky TiB2 is ultra-fine B2 phase and there has an orientation relationship [1210] TiB2//[001]B2, (1010) //(010)B2. In addition to the well-known grain refinement effect, boron addition can suppress the formation of metastable feathery and Widmastätten structure and broadens cooling-rate-range for the formation of fully lamellar structure, consequently, it improves thermal stability of the lamellar structure and accordingly prolongs the creep rupture life significantly. Another beneficial effect of boron addition is that boride can restrain discontinuous coarsening on lamellar grain boundary by pinning action and accelerates recrystallization of γ grain by introducing TiB2/matrix interfaces as nuclear sites during homogeneous treatment at 1150°C. Therefore, compared with boron-free alloy more homogeneous and refined near γ microstructure can be obtained in boron modified alloy.

The morphology and grain orientation of the surface and the cross section of CVD W coating on a single crystal Mo rod with an axial direction of 〈1 1 1〉 have been characterized by SEM and EBSD. An obvious preferred orientation growth has been found in the W coating. About 80% surface area of the W coating is covered by W grains with a normal direction within 10° around 〈1 0 1〉. A strong {1 0 1}〈1 1 1〉 texture has also been observed in the W coating. EBSD studies suggest that a combination of the Mo matrix introducing growth mechanism and the competing growth mechanism should be responsible for the preferred growth and texture formation.

Preliminary design and analysis for China helium-cooled solid breeder (CH HC-SB) test blanket module (TBM) for testing in ITER device have been carried out recently. In this paper, the design description, the performance analysis and the related ancillary systems for CH TBM are given. The key features of the design are based upon the breeder-outside-tube (BOT) concept, on the use of solid breeder ceramic material, of helium as coolant and tritium purge gas, of ferrite–martensite steel as structural material and of beryllium as neutron multiplier. Results show that the proposed TBM concept has the advantages of higher tritium breeding ratio (TBR), simple structure design and engineering feasibility.

The effect of 0.2 at.% boron addition on phase transformation of Ti–47.5Al–2Cr–2Nb alloy during cooling from the α single phase field was investigated. The room and elevated-temperature tensile properties, creep rupture properties of the boron-free alloy and the boron-modified alloy were compared. The results indicate a very strong effect of boron addition on α to γ phase transformation during continuous cooling at various rates. During air cooling and oil quenching, a large number of Widmanstatten colonies and feathery colonies form in the boron-free alloy, while in the boron-modified alloy there forms a fully lamellar microstructure without Widmanstatten and feathery colonies. A water quenched microstructure in the boron-free alloy consists of about 50 vol% massive transformed region and 50 vol% featureless untransformed region, whereas a 100 vol% massive transformed microstructure is formed in the boron-modified alloy during water quenching process. Due to the effect of boron addition on promoting the formation of fully lamellar microstructure during air cooling and oil quenching, the 760 °C/275 MPa creep rupture life of the boron-modified alloy is two times longer than that of the boron-free alloy when they are cooled from the α single phase field at the same cooling rates. In addition, the boron addition raises the yield strength at room and elevated-temperatures and improves the ductility at room temperature.

Grid-connected and island control of parallel inverters used in micro grid based on a variety of micro-source were introduced in this paper. Micro-grid in the connected mode should be able to operate automatically with the grid frequency and output high quality electricity in PQ control, and in island mode it can realize load power sharing of the parallel DGs in Droop control (1). Simultaneously, it should also ensure the stability of the load voltage and frequency in island mode with the droop-based controller which can make the micro-grid smoothly switching between the two operation modes. Finally, simulation of two inverters in the connected mode and island mode was introduced in MATLAB / SIMULINK; the simulation results show the effect of droop control and the load-sharing function. The results also indicate the feasibility and correctness of the control strategy.

In the surface stress detection system of the mine hoist machine drum, the wireless sensor nodes placed on the drum need to be powered by a battery. Since the sampling frequency is high and the wireless transmitting and receiving data is enormous, the battery needs to be replaced very frequently. To solve this problem, this paper designed wind-induced piezoelectric energy harvestingx8 device for wireless sensor node on the drum of mine hoist, which can charge the battery by obtaining the energy from the environment. In this paper, the structure of the energy harvesting device was introduced, the working principle of wind-induced piezoelectric energy harvesting device on the drum surface of the mine hoist was analyzed, and the piezoelectric bimorph cantilever beam energy harvesting circuit with ultra-low loss characteristics was designed. Based on these, we conducted several experiments with the wind- induced piezoelectric energy harvesting device. The result indicates that the final storage voltage can reach 4.4V at both ends of C3 in the piezoelectric energy harvesting circuit, which means it is able to charge the lithium ion battery.

Technology forecasting plays a fatal role for enterprise survival and development. Technology maturity of thermostat is predicted with the TMMS and patent data algorithms. Radar plot is drawn to indicate the evolutionary potential for the further improvements of thermostat. It is pointed out that thermostat will be getting more dynamic and smaller with the help of radar plot. KEYWORD: radar plot; thermostat; technology forecasting

The tungsten–rhenium couple was prepared by using glow plasma physical vapor deposition (PVD) on the isotropic fine grained graphite (IG) substrates. Diffusion anneals of the tungsten–rhenium couple were conducted at the temperature from 1100 °C to 1400 °C to investigate the inter-diffusion behaviors. The results showed that the thickness of the inter-diffusion zone increased with increasing annealing temperature. The relationship between the inter-diffusion coefficient and the annealing temperature accorded with the Arrhenius manner. The value of inter-diffusion activation energies was 189 kJ/mole (1.96 eV). The service time of tungsten–rhenium multilayer diffusion barrier was limited by the inter-diffusion for rhenium and tungsten rather than the diffusion of carbon in rhenium.

Defects of doped and neutron-irradiated TiAl alloys were investigated using positron annihilation lifetime and coincidence doppler broadening spectroscopies. In doped alloys, niobium additions replaced some atoms in the lattice, which maintains the ordered structure as undoped, while silicon additions induced Ti vacancies. After neutron irradiation, a number of vacancy-type defects were introduced, including some large vacancies, which can be congregated and hardly be eliminated by annealing at temperature above 1000 K. The vacancy-type defects in (Ti 51 Al 49 ) 98 Si 2 began to migrate at 452 K, which is lower than in Ti 51 Al 49 alloy. This probably resulted from vacancies induced by the addition of silicon, which facilitated atom migration and decreased initial recovery temperature.

From a comparison between the ILS interannual polar motion and that calculated from the ILS latitude data but with different combinations of the ILS stations, the ILS polar motion has been studied at interannual time scales. It has been concluded that the interannual polar motion reduced from the ILS observations is influenced by an unknown phenomenon of the Earth; the obtained polar motion is reflecting, at interannual time scales, the real motion of the pole at certain epochs only.

In this article, the BEM solution of the diffusion equation with a moving boundary is discussed. It is shown that the analytical time integration both for the 0- and 1-order modes lead to a special exponent–integral function and the reference time parameter τ will be important to the computational efficiency. In this article, the local time-dependent solution is used so that a series matrix computation can be reduced. Hence a new time marching scheme which is suitable to a moving boundary case is presented with some successful numerical tests.

Since nanocrystalline materials were first proposed by Gleiter et al. and as a result of their attractive properties, nanocrystalline materials of numerous compositions and structures have been prepared by different techniques among which mechanical attrition (MA) is an easy and effective method. In recent years synthesis of nanocrystalline composites, or nanophase composites have been studied extensively. The main methods used to synthesize nanophase composites by MA are mainly alloy power and ceramic powder together to form homogeneously distributed nanocrystalline metal/ceramic composites and milling element powders under atmosphere or medium to form metal/ceramic composites by reaction between elements and medium. Actually MA of immiscible systems may lead to the formation of a nanophase composite if two components can hardly dissolve into each other. In this paper mechanical alloying is studied for the immiscible Pb-Al and Fe-Cu systems.

Adaptive multiple subtraction based on blind 2D convolved mixtures separation exploits non-Gaussian maximization constraint on primaries to estimate the 2D matching filter. The 2D filter looks like a dip filter. However, there exist spurious or noisy filter impulse causing residual multiples or distorted primaries. Given the filter’s coefficients satisfy non-Gaussian distribution, we introduce the non-Gaussian maximization constraint of filters into the blind 2D convolved mixtures separation based method. The iterative reweighted least squares (IRLS) algorithm is used to estimate the 2D matching filter. Since the proposed method estimates the 2D matching filter with less noisy filter impulse, it can better remove residual multiples and preserve primaries compared with the blind 2D convolved mixtures separation based method and traditional least squares method.

In this paper, we propose an automatic approach for diffracted seismic noise (DSN) localization. In the proposed method, the apexes of the potential DSNs in each shot are first recognized to calculate their locations, respectively. After that, all these potential DSNs recognized in one seismic line are used together to improve the location estimations further, according to their locations distribution. By supposing that the location of one DSN is fixed or slowly changed during the seismic data acquisition, for a true DSN, its location estimates obtained from different shot gathers should focus together. Therefore, a clustering algorithm is applied to obtaining the location estimations of the final DSNs and removing the false recognized DSNs at the same time. After the DSNs are localized, they are flattened along their trajectories and extracted by multi-channel filters, as do the other existed methods. A real 3D marine data example demonstrates that the proposed method obtains some promising results.

The Beijing Spectrometer (BES) is a general purpose solenoidal detector at the Beijing Electron Positron Collider (BEPC). It is designed to study exclusive final states in e + e − annihilations at the center of mass energy from 3.0 to 5.6 GeV. This requires large solid angle coverage combined with good charged particle momentum resolution, good particle identification and high photon detection efficiency at low energies. In this paper we describe the construction and the performance of BES detector.