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The high resolution range profile can be obtained through coherent pulse compression processing in every coherent processing interval (CPI) for stepped frequency radars (SFR). The radar observation time can be divided into multiple CPIs. By utilising the temporal information inherent to a sequence of these range profiles, a time-range image containing the target motion information can be synthesised...
In this work, Er3+ doped and Er3+/Yb3+ co-doped glass ceramics in the GeS2 - Ga2S3 - CsCl system were prepared. The photoluminescence efficiency of the material depends largely on the local environment of the rare earth ions. It is particularly strong if the rare earth ions are situated inside crystals. By applying appropriate heat treatments to some glass compositions, it is possible to generate...
One of the privacy threats recognized in the use of LBS is represented by an adversary having information about the presence of individuals in certain locations, and using this information together with an (anonymous) LBS request to re-identify the issuer of the request associating her to the requested service. Several papers have proposed techniques to prevent this, assuming that the use of the service...
Proximity based services are location based services (LBS) in which the service adaptation depends on the comparison between a given threshold value and the distance between a user and other (possibly moving) entities. While privacy preservation in LBS has lately received much attention, very limited work has been done on privacy-aware proximity based services. This paper describes the main privacy...
Protecting privacy of mobile users of location-based services is a currently interesting research problem. Most protection techniques can be categorized into either those providing location privacy or those guaranteeing k-anonymity. A mobile user (i) has location privacy if, when he makes an LBS request, adversaries cannot tell his location precise enough to cause privacy concerns, and (ii) has k-anonymity...
Laser non-contact precision measuring method of CNC machine tools under the high feed rate condition was put forward. The method combines the laser interferometer with the measurement principle of the double ball bar (DBB), and can measure the machine tool precision under the high feed rate condition. Two laser interferometers used as measuring the displacements and feed rate data along circular interpolation...
A deception jamming method is proposed, which can be used by a team of UAVs to deceive air defense radar network. To make the phantom tracks undistinguishable from the tracks of the true targets, the position geometry of radars and UAVs was studied, and the analytical expression of relationships between the motion of the UAVs and that of the phantom tracks have been derived, which can be used to precisely...
Processing parameters for an optimized fabrication of micro structures with dimensions ranging from 20 mum to 4 mm channel width and up to 2 mm height providing height/width aspect ratios of 10/1 have been investigated for 3 different LTCC-tapes (low temperature co-fired ceramics). The fabrication process is based on an optimized NdYAG-laser machining process and an adapted isostatic single step lamination...
A decision guidance management system (DGMS) is a productivity platform for fast development of applications that require a closed-loop data acquisition, learning, prediction, and decision optimization. This paper introduces the DGMS concept, and the first DGMS data model with its query language, DG-SQL. The DGMS data model is an extension of the relational model with probability distributions over...
In stream join processing with limited memory, uniform random sampling is useful for approximate query evaluation. In this paper, we address the problem of reservoir sampling over memory-limited stream joins. We present two sampling algorithms, reservoir join-sampling (RJS) and progressive reservoir join-sampling (PRJS). RJS is designed straightforwardly by using a fixed-size reservoir sampling on...
Reservoir sampling is a well-known technique for sequential random sampling over data streams. Conventional reservoir sampling assumes a fixed-size reservoir. There are situations, however, in which it is necessary and/or advantageous to adaptively adjust the size of a reservoir in the middle of sampling due to changes in data characteristics and/or application behavior. This paper studies adaptive...
Nowadays, wireless sensor networks have been widely used in many monitoring applications. Due to the low quality of sensors and random effects of the environments, however, it is well known that the collected sensor data are noisy. Therefore, it is very critical to clean the sensor data before using them to answer queries or conduct data analysis. Popular data cleaning approaches, such as the moving...
A general consensus is that the proliferation of location- aware devices will result in a diffusion of location-based services. Privacy preservation is a challenging research issue for this kind of service. A possible solution consists of ensuring users' anonymity, i.e., ensuring that the user issuing a request is indistinguishable, among a group of users, by any attacker who has access to the service...
In this paper we extend the notion of k-anonymity in the context of databases with timestamped information in order to naturally define k-anonymous views of temporal data. We also investigate the problem of obtaining these views. We show that known generalization techniques, despite being applicable under certain conditions, have some limitations, and propose a new generalization algorithm based on...
The number of active sensors in a wireless sensor network has been proposed as a measure, albeit limited, for quality of service (QoS) for it dictates the spatial resolution of the sensed parameters. In very large sensor network applications, the number of sensor nodes deployed may exceed the number required to provide the desired resolution. Herein we propose a method, dubbed predictive QoS control...
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