Range-Based Localization in Wireless Networks Using Density-Based Outlier Detection

Node localization is commonly employed in wireless networks. For example, it is used to improve routing and enhance security. Localization algorithms can be classified as range-free or range-based. Range-based algorithms use location metrics such as ToA, TDoA, RSS, and AoA to estimate the distance between two nodes. Proximity sensing between nodes is typically the basis for range-free algorithms. A tradeoff exists since range-based algorithms are more accurate but also more complex. However, in applications such as target tracking, localization accuracy is very important. In this paper, we propose a new range-based algorithm which is based on the density-based outlier detection algorithm (DBOD) from data mining. It requires selection of the K-nearest neighbours (KNN). DBOD assigns density values to each point used in the location estimation. The mean of these densities is calculated and those points having a density larger than the mean are kept as candidate points. Different performance measures are used to compare our approach with the linear least squares (LLS) and weighted linear least squares based on singular value decomposition (WLS-SVD) algorithms. It is shown that the proposed algorithm performs better than these algorithms even when the anchor geometry about an unlocalized node is poor.

Model-Based Split-Range Algorithm for the Temperature Control of a Batch Reactor

In the manufacturing processes of high value-added products in the pharmaceutical, fine chemical polymer and food industry, insufficient control might produce off-grade products. This can cause significant financial losses, or in the pharmaceutical industry, it can result in an unusable batch. In these industries, batch reactors are commonly used, the control of which is essentially a problem of temperature control. In the industry, an increasing number of heating-cooling systems utilising three different temperature levels can be found, which are advantageous from an economic point of view. However, it makes the control more complicated. This paper presents a split-range designing technique using the model of the controlled system with the aim to design a split-range algorithm more specific to the actual sys- tem. The algorithm described provides high control performance when using it with classical PID-based cascade temperature control of jacketed batch reactors;however, it can be used with or as part of other types of controllers, for ex- ample, model-based temperature controllers. The algorithm can be used in the case of systems where only two as well as where three temperature levels are used for temperature control. Besides the switching between the modes of opera- tion and calculating the value of the manipulated variable, one of the most important functions of the split-range algo- rithm is to keep the sign of the gain of the controlled system unchanged. However, with a more system-specific split-range solution, not only can the sign of the gain be kept unchanged, but the gain can also be constant or less de- pendent on the state of the system. Using this solution, the design of the PID controller becomes simpler and can be implemented in existing systems without serious changes.

The Equilibrium Range of Wind Wave Spectra: an Explanation Based on White Noise

Laboratory experiments and field observations show that the equilibrium range of wind wave spectra presents a – 4 power law when it is scaled properly. This feature has been attributed to energy balance in spectral space by many researchers. In this paper we point out that white noise on an oscillation system can also lead to a similar inverse power law in the corresponding displacement spectrum, implying that the – 4 power law for the equilibrium range of wind wave spectra may probably only reflect the randomicity of the wind waves rather than any other dynamical processes in physical space. This explanation may shed light on the mechanism of other physical processes with spectra also showing an inverse power law, such as isotropic turbulence, internal waves, etc.

Source Range Estimation Based on Pulse Waveform Matching in a Slope Environment

An approach of source range estimation in an ocean environment with sloping bottom is presented. The approach is based on pulse waveform correlation matching between the received and simulated signals. An acoustic prop- agation experiment is carried out in a slope environment. The pulse signal is received by the vertical line array, and the depth structure can be obtained. For the experimental data, the depth structures of pulse waveforms are different, which depends on the source range. For a source with unknown range, the depth structure of pulse waveform can be first obtained from the experimental data. Next, the depth structures of pulse waveforms in dif- ferent ranges are numerically calculated. After the process of correlating the experimental and simulated signals, the range corresponding to the maximum value of the correlation coefficient is the estimated source range. For the explosive sources in the experiment with two depths, the mean relative errors of range estimation are both less than 7%.

Visual Passive Ranging Method Based on Re-entrant Coaxial Optical Path and Experimental Verification

To overcome the shortcomings of the traditional passive ranging technology based on image, such as poor ranging accuracy, low reliability and complex system, a new visual passive ranging method based on re-entrant coaxial optical path is presented. The target image is obtained using double cameras with coaxial optical path. Since there is imaging optical path difference between the cameras, the images are different. In comparison of the image differences, the target range could be reversed. The principle of the ranging method and the ranging model are described. The relationship among parameters in the ranging process is analyzed quantitatively. Meanwhile,the system composition and technical realization scheme are also presented. Also, the principle of the method is verified by the equivalent experiment. The experimental results show that the design scheme is correct and feasible with good robustness. Generally, the ranging error is less than 10% with good convergence. The optical path is designed in a re-entrant mode to reduce the volume and weight of the system. Through the coaxial design,the visual passive range of the targets with any posture can be obtained in real time. The system can be widely used in electro-optical countermeasure and concealed photoelectric detection.

On the potential to predetermine dominant tree species based on sparse-density airborne laser scanning data for improving subsequent predictions of species-specific timber volumes

Background： Tree species recognition is the main bottleneck in remote sensing based inventories aiming to produce an input for species-specific growth and yield models. We hypothesized that a stratification of the target data according to the dominant species could improve the subsequent predictions of species-specific attributes in particular in study areas strongly dominated by certain species. Methods： We tested this hypothesis and an operational potential to improve the predictions of timber volumes, stratified to Scots pine, Norway spruce and deciduous trees, in a conifer forest dominated by the pine species. We derived predictor features from airborne laser scanning （ALS） data and used Most Similar Neighbor （MSN） and Seemingly Unrelated Regression （SUR） as examples of non-parametric and parametric prediction methods, respectively Results： The relationships between the ALS features and the volumes of the aforementioned species were considerably different depending on the dominant species. Incorporating the observed dominant species inthe predictions improved the root mean squared errors by 13.3-16.4 % and 12.6-28.9 % based on MSN and SUR, respectively, depending on the species. Predicting the dominant species based on a linear discriminant analysis had an overall accuracy of only 76 % at best, which degraded the accuracies of the predicted volumes. Consequently, the predictions that did not consider the dominant species were more accurate than those refined with the predicted species. The MSN method gave slightly better results than models fitted with SUR. Conclusions： According to our results, incorporating information on the dominant species has a clear potential to improve the subsequent predictions of species-specific forest attributes. Determining the dominant species based solely on ALS data is deemed challenging, but important in particular in areas where the species composition is otherwise seemingly homogeneous except being dominated by certain species.

A 330-500 GHz Zero-Biased Broadband Tripler Based on Terahertz Monolithic Integrated Circuits

A 330-500 GHz zero-biased broadband monolithic integrated tripler is reported. The measured results show that the maximum efficiency and the maximum output power are 2% and 194μW at 348 GHz. The saturation characteristic test shows that the output i dB compression point is about -8.5 dBm at 334 GHz and the maximum efficiency is obtained at the point, which is slightly below the 1 dB compression point. Compared with the conventional hybrid integrated circuit, a major advantage of the monolithic integrated circuit is the significant improvement of reliability and consistency. In this work, a terahertz monolithic frequency multiplier at this band is designed and fabricated.

Time-optimal rendezvous transfer trajectory for restricted cone-angle range solar sails

The advantage of solar sails in deep space exploration is that no fuel consumption is required. The heliocentric distance is one factor influencing the solar radiation pressure force exerted on solar sails. In addition, the solar radiation pressure force is also related to the solar sail orientation with respect to the sunlight direction. For an ideal flat solar sail, the cone angle between the sail normal and the sunlight direction determines the magnitude and direction of solar radiation pressure force. In general, the cone angle can change from 0° to 90°. However, in practical applications, a large cone angle may reduce the efficiency of solar radiation pressure force and there is a strict requirement on the attitude control. Usually, the cone angle range is restricted less more than an acute angle （for example, not more than 40°） in engineering practice. In this paper, the time-optimal transfer trajectory is designed over a restricted range of the cone angle, and an indirect method is used to solve the two point boundary value problem associated to the optimal control problem. Relevant numerical examples are provided to compare with the case of an unrestricted case, and the effects of different maximum restricted cone angles are discussed. The results indicate that （1） for the condition of a restricted cone-angle range the transfer time is longer than that for the unrestricted case and （2） the optimal transfer time increases as the maximum restricted cone angle decreases.

Polymerization of Norbornene via an Iron-Based Complex/MAO Catalytic System

Polynorbornenes were synthesized in the presence of an iron based catalyst, 2,6-bis[1-(2,6-diisopropyl-phenylimino)ethyl]pyridine iron(Ⅱ) dichloride. The FTIR, 1H NMR and 13C NMR analysis results revealed that the structure of the obtained polynorbornenes consisted of vinyl addition polymer substructures without any ring-opening structures. The polymers were amorphous with a short-range order, displayed in the WAXD(wide angle X-ray diffraction) diagrams. The glass transition temperatures ranged from 200 to 400 ℃. The effects of the polymerization reaction conditions, such as Al/Fe molar ratio and toluene/CH_2Cl_2 volume ratio, on the activity, intrinsic viscosity and T_g were also studied.

Decreasing trend in prostate cancer with high serum prostate-specific antigen levels detected at first prostate-specific antigen-based population screening in Japan

To clarify the recent trends in prostate-specific antigen （PSA） distribution in men in Japan, we analyzed the PSA distributions of men undergoing PSA-based population screening. We summarized the annual individual data of PSA-based population screening in Kanazawa, Japan, from 2000 to 2011, and analyzed baseline serum PSA values of the participants at the first population screening. Serum PSA distributions were estimated in all participants and those excluding prostate cancer patients according to age. From 2000 to 2011, 19 620 men participated aged 54-69 years old in this screening program. Mean baseline serum PSA level of all participants at the first screening was 2.64 ng m1-1 in 2000, and gradually decreased to approximately 1.30 ng ml-I in 2006. That of participants excluding prostate cancer patients was 1.46 ng m1-1 in 2000, and there was no remarkable change during the study period. The 95t＂ percentiles in the participants excluding prostate cancer patients detected at the first population screening of men aged 54-59, 60-64, and 65-69 years old were 2.90, 3.60, and 4.50 ng m1-1, respectively. After the commencement of population screening, the proportion of prostate cancer patients with high serum PSA levels decreased. However, there were no changes in serum PSA levels in men without prostate cancer. Age-specific PSA reference level of men without prostate cancer in Japan was similar to that in China and Korea.

SELECTING CLUSTER MODEL IN Sn - BASED SOLDER ALLOY DESIGN WITH DV - X_α CALCULATION METHOD

Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in which different cluster models were adopted to calculate electron structure.It is proved that some regulations must be taken into ac- count in order to carry out alloy design calculation successfully,which are described in this paper in detail.

Preparation and the Pore Structure of Viscose-based Activated Carbon Fibers Treated with Pretreatment Reagents

The viscose rayon was pretreated with four different pre-treatment reagents respectively, and the preparation ofactivated carbon fibers (ACF) was performed undersame carbonizing and activating conditions. The poresize distribution, the specific surface area, and the porestructure parameter of these viscose - based ACF werestudied by using quartz spring balance BET- weightmethod. The experiment result indicates that the poresize distribution and the pore structure parameter ofACF is varied by using different pretreatment reagents.

GRAPHICAL COMPUTING METHOD ON FOUR-BAR LINKAGE(1)——Inflexion Circle,Focal Axis,Ball's Point,Centering-point Curve and Circling-point Curve For Four ISPs,Coupler Curves Based on Ball's Points——

By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we make aspecial study about centering- point curve and circling- point curve and couplercurves based on Ball’s points.

WAVELET-BASED ESTIMATORS OF MEAN REGRESSION FUNCTION WITH LONG MEMORY DATA

This paper provides an asymptotic expansion for the mean integrated squared error （MISE） of nonlinear wavelet-based mean regression function estimators with long memory data. This MISE expansion, when the underlying mean regression function is only piecewise smooth, is the same as analogous expansion for the kernel estimators.However, for the kernel estimators, this MISE expansion generally fails if the additional smoothness assumption is absent.

Lagrangian formulation of continuum with internal long-range interactions

Based on a new definition of nonlocal variable,this paper establishes the Lagrangian formulation for continuum with internal long-range interactions.Distinguished from the existing theories,the nonlocal term in the Lagrangian formulation automatically satisfies the zero mean condition determined by the action and reaction law.By this formulation,elastic wave in a rod with the internal long-range interactions is investigated.The dispersion of the elastic wave is predicted.

Theory and Application of Natural-Based Wavelet Method

Wavelet method is often used in analyzing trend and period of time sequence. When using wavelet method one serious problem is different chosen wavelet basis and scale would lead to different results. Sometimes, the results vary greatly. To overcome this problem and to improve the accuracy and efficiency, a new method denoted by Natural-based Wavelet Method is introduced and extended. It can be proved that the proposed method in fact is a special class of discrete wavelet. At first, two numerical examples are designed to show the capacity of the novel method. Second, this method is applied to a precipitation series. According to wavelet analysis and short-range precipitation prediction, this precipitation exists a faintly increasing trend. Through the analysis, the studied precipitation has two major periods: 11 and 41 years. The results validate that the Natural-based Wavelet Method used in application of multi-complicated observed data is suitable. It is easy to write the source code of the proposed method. When new information appears, new information can be easily added into the original sequence, this is another advantage of the proposed method.

Half space object classification via incident angle based fusion of radar and infrared sensors

In this paper,we introduce an incident angle based fusion method for radar and infrared sensors to improve the recognition rate of complex targets under half space scenarios,e.g.,vehicles on the ground in this paper.For radar sensors,convolutional operation is introduced into the autoencoder,a“winner-take-all(WTA)”convolutional autoencoder(CAE)is used to improve the recognition rate of the radar high resolution range profile(HRRP).Moreover,different from the free space,the HRRP in half space is more complex.In order to get closer to the real situation,the half space HRRP is simulated as the dataset.The recognition rate has a growth more than 7%com-pared with the traditional CAE or denoised sparse autoencoder(DSAE).For infrared sensor,a convolutional neural network(CNN)is used for infrared image recognition.Finally,we com-bine the two results with the Dempster-Shafer(D-S)evidence theory,and the discounting operation is introduced in the fusion to improve the recognition rate.The recognition rate after fusion has a growth more than 7%compared with a single sensor.After the discounting operation,the accuracy rate has been improved by 1.5%,which validates the effectiveness of the proposed method.

Comparison of Indoor Localization Systems Based on Wireless Communications

Localization using a Wireless Sensor Network (WSN) has become a field of interest for researchers in the past years. This information is expected to aid in routing, systems maintenance and health monitoring. For example, many projects aiming to monitor the elderly at home include a personal area network (PAN) which can provide current location of the patient to the medical staff. This article presents an overview of the current trends in this domain. We introduce the mathematical tools used to determine position then we introduce a selection of range-free and range-based proposals. Finally, we provide a comparison of these techniques and suggest possible areas of improvement.

Measurement on soil deformation caused by expanded-base pile in transparent soil using particle image velocimetry (PIV)

A new small-scale geotechnical physical model in 1-g and unconfined condition, combining the transparent soil, close-range photogrammetry and particle image velocimetry(PIV), was employed, which provides a non-intrusively internal deformation measurement approach to monitor the internal deformation of soil caused by expanded-base pile jacking with casing. The transparent soil was made of fused quartz and its refractive index matched blended oil, adding reflective particles(glass beads). Closerange photogrammetry was employed to record the images of the process of casing jacking and extraction in transparent soil, allowing the use of Matlab-based Geo-PIV to figure out the displacement field converted from image space to object space. Analysis of test results indicates that the maximum displacement caused by casing jacking for expandedconical-base pile is decreased by 29% compared with that for expanded-flat-base pile. The main movement happens at the early stage of casing extraction. The maximum displacement caused by casing extraction for the conical base is about 43% of that for the flatbase, while the affected zone caused by casing extraction for the conical base accounts for about 1/3 of that for the flat base. The contraction for horizontal displacements tends to decrease with the depth increasing. By contrast, the contraction under pile base decreases with the increasing of displacement. The displacements generated by jacking a conventional pile having a diameter equal to the casing diameter of the expanded-base pile were comparable to the net displacement taking place due to expanded-base pile installation for the conical base pile.

NEW SOLID BASE DERIVED FROM AIPO4-5 SUPPORTED KF

Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm- band of bidentate carbonate in CO2 adsorption.After pre-treated above 823K. 5%KF/AlPO4-5exhibited basic catalytic activity in the isomerization of butenes at 273K. and the activity increasedwith the pre-treatment temperature up to 923K.