Pilot Symbol Assisted Hybrid Detection for OFDM‐Based Spatial Multiplexing Systems

In this paper, we provide a new detection scheme for a pilot symbol assisted interference nulling and cancellation operation to reduce unexpected effects owing to parallel transmission in orthogonal frequency division multiplexing (OFDM)‐based spatial multiplexing systems. We have shown that the investigated OFDM vertical Bell laboratories layered space time (VBLAST) detection based on hybrid processing performs better than ordinary OFDM‐VBLAST detections based on serial processing and parallel processing, respectively.     

Analysis and Optimization of Passive Intermodulation in Microwave Coaxial Cavity Filters

We studied how the passive intermodulation (PIM) power arising in air cavity filters could be calculated and how the design of the filter could be optimized in order to reduce the amplitude of the PIM signal. To do this, using simulated results, we optimized the various parameters of a filter. PIM in an air cavity filter depends on the power dissipated in its cavities. A reduction of this power loss therefore decreases the PIM power in the air cavity filter. Our experimental results confirm that it is possible to design and produce air cavity filters that generate low PIM signals.     

Numerical analysis of optimum timer value for time-based locationregistration scheme

In this letter, we analyze a time-based update method in location management and calculate the optimal time-interval. We obtain the probability that a mobile terminal (MT) is j rings away from the center cell. And using these values, an exact analysis is made for the time-based location management cost. From the result, when the time-based method is applied to location update, we can get the optimal time-interval which minimizes the location management cost     

对三孔隙度交会图法进行测井曲线标准化的改进

由于三孔隙度交会图法不能解决欠压实、疏松岩性地层的测井曲线标准化问题,所以对其进行了改进。根据 东营凹陷一些关键井的测井资料,讨论了在测井井眼条件良好时选取纯砂岩、纯水层用交会图法进行测井曲线标 准化的方法,即引入声波地层因素公式后,欠压实的高孔隙地层的声波时差与补偿中子、声波时差与密度的关系均 为非线性关系,应用新的关系对三孔隙度资料进行测井曲线标准化。改进后的方法已得到东营凹陷13口探井资 料的验证是可行的。     

“Multipoint Force Feedback” Leveling of Massively Parallel Tip Arrays in Scanning Probe Lithography

Nanoscale patterning with massively parallel 2D array tips is of significant interest in scanning probe lithography. A challenging task for tip‐based large area nanolithography is maintaining parallel tip arrays at the same contact point with a sample substrate in order to pattern a uniform array. Here, polymer pen lithography is demonstrated with a novel leveling method to account for the magnitude and direction of the total applied force of tip arrays by a multipoint force sensing structure integrated into the tip holder. This high‐precision approach results in a 0.001° slope of feature edge length variation over 1 cm wide tip arrays. The position sensitive leveling operates in a fully automated manner and is applicable to recently developed scanning probe lithography techniques of various kinds which can enable “desktop nanofabrication.”     

A new approach for preparation of oil-soluble bimetallic dispersed catalyst from layered ammonium nickel molybdate

A new route via the coating of layered ammonium nickel molybdate with oleic acid was developed to prepare an oil-soluble bimetallic dispersed catalyst for the hydrocracking reaction of heavy oil. The layered ammonium nickel molybdate, termed Ni-LTM precursor, was synthesized by precipitation, and the NiMo oleate complex was prepared with the oleic acid serving as an organic ligand. The prepared materials were characterized with X-ray diffraction, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. It was found that the oleic acid is chemisorbed as a carboxylate onto the Ni-LTM nanoparticles, specifically on Ni-O bond. Also, the catalytic activities were compared between the NiMo oleate complex and other ordinary monometallic dispersed catalysts. The NiMo oleate complex showed excellent catalytic activity, demonstrating its potential to be applied as a novel dispersed catalyst.     

Switching-mode dependence of inductive noise in VLSI power bus lines

The switching-mode dependence of inductive noise on the power bus lines has been investigated. As the maximum operation frequency of the very large-scale integration is determined by the slowest response in the critical path, suppression of inductive noise in power lines is crucial. Circuits with 50% duty cycle are almost free of inductive noise. Contrarily, the low duty cycle circuits are highly subject to the inductive noise thus the decoupling capacitor needs to be carefully implemented, considering the line inductance and effective frequency. The conventional "10/spl times/ of switching-capacitor" rule-of-thumb is not applicable to decoupling capacitor implementation and can cause worse inductive noise than a "no capacitor" situation.     

A novel retrieval approach reflecting variability of syntactic phrase representation

In this paper, we introduce variability of syntactic phrases and propose a new retrieval approach reflecting the variability of syntactic phrase representation. With variability measure of a phrase, we can estimate how likely a phrase in a given query would appear in relevant documents and control the impact of syntactic phrases in a retrieval model. Various experimental results over different types of queries and document collections show that our retrieval model based on variability of syntactic phrases is very effective in terms of retrieval performance, especially for long natural language queries.