The Riesz Decomposition of Set-Valued Superpramart

The paper proves the convergence theorem of set-valued Superpramart in the sense of weak convergence under the X* separable condition. Using support function and results about real-valued Superpramart, we give the Riesz decomposition of set-valued Superpramart.

Multi-factor high-order intuitionistic fuzzy timeseries forecasting model

Fuzzy sets theory cannot describe the neutrality degreeof data, which has largely limited the objectivity of fuzzy time seriesin uncertain data forecasting. With this regard, a multi-factor highorderintuitionistic fuzzy time series forecasting model is built. Inthe new model, a fuzzy clustering algorithm is used to get unequalintervals, and a more objective technique for ascertaining membershipand non-membership functions of the intuitionistic fuzzy setis proposed. On these bases, forecast rules based on multidimensionalintuitionistic fuzzy modus ponens inference are established.Finally, contrast experiments on the daily mean temperature ofBeijing are carried out, which show that the novel model has aclear advantage of improving the forecast accuracy.

A Ring Signature Based on LDGM Codes

McEliece cryptosystem is a public key cryptosystem that combines channel coding and encryption,and the oldest PKC that is conjectured to be postquantum secure.To decrease the key size of the original scheme,alternative codes have been adopted to replace Goppa codes.In this paper,we propose a ring signature using low-density generator-matrix codes.Our new scheme satisfies anonymity and existential unforgeability under chosen message attacks(EUFCMA).As for efficiency,the number of decoding operations has been reduced largely compared with ZLC ring signature,and the size of the public key is about 0.2%of the ZLC

Study on Surface Plotting Methods in Parts Plotting

According to the factors that confirm the shape of surface, it is classified into two categories： arc surface and curve surface The method to confirm the category of surfaces and the plotting methods are discussed in this paper, which provide guidance for parts plotting.

Formation and Movement of Groundwater in the Thick Loess-Palaeosol Sequences of the Chinese Loess Plateau

Permeability and water-bearing space are important hydrological characteristics of the loess strata. In this study a systematic experiment was conducted to measure the magnetic susceptibility, grain size, porosity, and infiltration rate of the loess and palaeosol layers on a loess tableland of the central Chinese Loess Plateau, in order to investigate the differences in hydrological conditions between the loess and palaeosol layers. The magnetic susceptibility of the loess layer was lower than that of the palaeosol layer, but the average quasi-steady infiltration rate was about 0.31 mm min^(-1) higher, the coarse silt and very fine sand contents were about7.1% greater, and the porosity was about 5.7% higher. These differences were mainly due to pedogenesis, which was affected by the Quaternary climate. The pedogenesis differences between the loess and palaeosol layers resulted in hydrological property differences in terms of permeability and water-bearing space. The loess layer had a higher permeability and more water-bearing space than the palaeosol layer, which meant that the loess layer is more likely to form aquifers and the palaeosol layer is more prone to form aquitards.The groundwater in the loess strata had a multilayered characteristic, which depended on the relative impermeability of palaeosol layer and the alternate deposition of loess-palaeosol layers. The hydrological characteristics of the loess strata demonstrated that the Quaternary climate had an important control function on the formation and movement of groundwater. This knowledge provides a reliable theoretical basis for water resource development and utilization on the Chinese Loess Plateau, and this study extends the application of Quaternary climate change theory to hydrological systems in loess deposits.

Discovery and study of silver sulfate mineral in S_5 from the eastern suburb of Xi'an

The paleosol samples from the fifth layer of the loess profile at Renjiapo in the eastern suburb of Xi'an are observed and analyzed using electron microscope and energy spectrum. Minerals such as AgSO4 and molybdenum, which are rare to find and can indicate typical dry climate environment, are found in this layer of paleosol. Secondary mineral is usually granular form of ellipsoidal and crystallization, and has the characteristics of chemical precipitating crystallization of apertures and fracture. Molybdenum minerals have the characteristics of colloidal substances. There are two kinds of secondary minerals. One is silver sulfate mineral and the other is silver oxide mineral. The movement of secondary silver, molybdenum and cobalt minerals, new clay mineral, Fe2O3 and Al2O3 indicates that S5 has experienced strong chemical weathering and mineral dissolution during its development. Silver, molybdenum, and cobalt can be released from primary minerals. During that period, the precipitation was abundant in Xi'an where soil reached an acidity stage of chemical weathering. At the later development stage of paleosol in the lowest part of S5, warm and wet monsoon climate had changed to dry and non-monsoon climate. In the period of the formation of AgSO4, which is easier to dissolve than CaSO4, a dry and non-monsoon climate was present in the Guanzhong Plain. Strong evaporation resulted in the accumulation of SO42-in the soil water solution and the formation of AgSO4. At that time, summer monsoon of East Asia was weak and did not cross Qinling Mountains to reach Guanzhong Plain. And at that time, the precipitation in Xi'an was less than 300 mm, and it was drier then in Xi'an than at present in Lanzhou.

Indoor massive multiple-input multiple-output channel characterization and performance evaluation

We present a measurement campaign to characterize an indoor massive multiple-input multiple-output (MIMO) channel system, using a 64-element virtual linear array, a 64-element virtual planar array, and a 128-element virtual planar array. The array topologies are generated using a 3D mechanical turntable. The measurements are conducted at 2, 4, 6, 11, 15, and 22 GHz, with a large bandwidth of 200 MHz. Both line-of-sight (LOS) and non-LOS (NLOS) propagation scenarios are considered. The typical channel parameters are extracted, including path loss,shadow fading, power delay profile, and root mean square (RMS) delay spread. The frequency dependence of these channel parameters is analyzed. The correlation between shadow fading and RMS delay spread is discussed. In addition, the performance of the standard linear precoder—the matched filter, which can be used for intersymbol interference (ISI) mitigation by shortening the RMS delay spread, is investigated. Other performance measures,such as entropy capacity, Demmel condition number, and channel ellipticity, are analyzed. The measured channels,which are in a rich-scattering indoor environment, are found to achieve a performance close to that in independent and identically distributed Rayleigh channels even in an LOS scenario.

An Efficient Location Privacy Protection Scheme Based on the Chinese Remainder Theorem

Traditional k-anonymity schemes cannot protect a user＇s privacy perfectly in big data and mobile network environments. In fact, existing k-anonymity schemes only protect location in datasets with small granularity. But in larger granularity datasets, a user＇s geographical region-location is always exposed in realizations of k-anonymity because of interaction with neighboring nodes. And if a user could not find enough adjacent access points, most existing schemes would be invalid. How to protect location information has become an important issue. But it has not attracted much attention. To solve this problem, two location-privacy protection models are proposed. Then a new generalized k-anonymity Location Privacy Protection Scheme based on the Chinese Remainder Theorem （LPSS-CRT） in Location-Based Services （LBSs） is proposed. We prove that it can guarantee that users can access LBSs without leaking their region-location information, which means the scheme can achieve perfect anonymity. Analysis shows that LPPS-CRT is more secure in protecting location privacy, including region information, and is more efficient, than similar schemes. It is suitable for dynamic environments for different users＇ privacy protection requests.

A constant loop bandwidth fractional-N frequency synthesizer for GNSS receivers

A constant loop bandwidth fractionalN frequency synthesizer for portable civilian global navigation satellite system （GNSS） receivers implemented in a 130 nm 1P6M CMOS process is introduced. Via discrete work ing regions, the LCVCO obtains a wide tuning range with a simple structure and small VCO gain. Spur suppression technology is proposed to minimize the phase offset introduced by PFD and charge pumps. The optimized band width is maintained by an auto loop calibration module to adjust the charge pump current when the PLL output frequency changes or the temperature varies. Measurement results show that this synthesizer attains an inband phase noise lower than 93 dBc at a 10 kHz offset and a spur less than 70 dBc; the bandwidth varies by 4 3% for all the GNSS signals. The whole synthesizer consumes 4.5 mA current from a 1 V supply, and its area （without the LO tested buffer） is 0.5 mm2.