Daniel Petrisor

Lane mark detection using Hough transform

A lane mark detection system is a driver assistance tool that automatically recognizes the lane mark painted on the road and the lane that he is travelling in. Such a system can warn the driver when has the tendency to move out from the lane, without being aware of it. This kind of system is a part of Advanced Driver Assistance Systems (ADAS), systems that has the goal to improve road safety. In this paper we propose an algorithm that automatically emphasizes the lane marks and recognizes them from digital images, by the use of Hough transform.

Detection and recognition of traffic signs using Gabor filters

The paper proposes a three steps algorithm that automatically detects, classifies and recognizes traffic signs from images taken from a car running along European road. Traffic signs are detected by analyzing the color information contained in the images using HSV color space. Detected signs are then classified using correlation with standard sign shapes. The recognition step uses the minimum distance classification based on calculating the Euclidean distance between two feature vectors composed using a Gabor filter with different parameters.

Algorithm for face and eye detection using colour segmentation and invariant features

The paper presents an algorithm designed to face and facial features (eyes, eyebrows) detection. First, human skin regions are segmented and processed by morphological operators to detect the human face. After the face has been detected, a series of parameters that will be taken into account by the eyes detection stage are calculated. The most important parameters are face orientation and distance between the eyes.

Virtual instrument developed for adcon weather station

This paper presents a virtual instrument for communication with a weather station that transmits information on measured environmental parameters using a radio telemetry units. The user interface is built in LabVIEW visual programming environment. This makes a PC serial or TCP/IP communication between a terminal and the central unit of the weather station, the information received is decoded and played back using the user interface program.

Programmable active filters based on digital potentiometers

The digital potentiometers are flexible devices allowing many of the applications of the mechanical trimming to be replaced by a solid state solution. In this paper, we address issues related to the use of the digital potentiometers in the active filter design, in order to implement programmable analog functions such as controlling the corner frequency and filter type. Also, we propose here a simple interfacing solution that allows for quickly configuring not only programmable filters, but other common circuits employing I2C digital potentiometers.

Pore water pressure sensor for landslide prediction

The paper presents a cost effective pore water pressure sensor (PWP) for landslide prediction, based on an integrated silicon pressure sensor. The sensor can be associated with a landslide sensor or can work independently. The aim of the landslide sensor is to detect the wetting condition and the tiny displacements of the ground. The pore water pressure has a simple construction, by measuring the pressure of the air in a small enclosure, air that is compressed by the water table. The pressure is measured with a silicon pressure sensor and it is converted in mm water column. Depending on the underground structure, many such sensors are necessary at different levels. The information is collected at the ground level via a serial point to multipoint network. The sensor has a low cost, fine accuracy, low power consumption and is easy to install.

Multiaxis inclinometer for in depth measurement of landslide movements

Purpose – The paper aims to present a device devoted to detect and measure earth displacements produced by landslides. This device is an inclinometer type geotechnical instrument. It is widely known that landslides are categorized among the most destructive disasters that yearly produce huge damages and even human lives losses. Design/methodology/approach – The principle of operation is based on measuring the deformation produced during soil layers sliding to a rod vertically mounted into the ground. The rod deformation is detected by highly sensitive strain gauges developed by authors using the stress impedance effect occurring in non-magnetostrictive magnetic amorphous microwires. The gauges are mounted in bridge configurations along the rod, beside the corresponding analogue and digital signal processing circuitry. Findings – The landslide transducer is able to calculate the displacement of the soil layers at different levels of depth and the direction of the landslide. It has been tested in laboratory...

Implementation of a landslide monitoring system as a wireless sensor network

Landslides have always been one of the most catastrophic natural phenomena. Continuous monitoring and warning as early as possible about the beginning of such a disaster may lead to avoidance of losses of human lives. With this aim, we have developed a monitoring system structured as a wireless sensor network equipped with very sensitive transducers, capable of measuring in real time the direction and magnitude of soil layers displacements with resolutions less than 1 mm. Beside the above two parameters, the system is able to estimate the degree of glide of the subsurface soil layers owed to its possibility of in-depth measurement. The transducer is conceived as an inclinometer possessing as sensitive elements highly sensitive strain gages developed by our team on the basis of magnetic effects occurring in amorphous magnetic microwires. More such transducers are mounted on a certain area known in advance as a landslide-prone and connected in a network able to wirelessly communicate and transmit on-line data to a monitoring center. Details related to network construction, as well as on the involved protocols are provided in the paper.

A study of changes in image contrast with various algorithms

The contrast enhancement is an important part of the image enhancement process. The visual details become more visible in an image with a high level of contrast. There are more techniques to improve a contrast image. In this paper we analyze the contrast modification by three main methods: the histogram equalization method, local histogram equalization (LHE) method and contrast limited adaptive histogram equalization (CLAHE) method. The degree of contrast enhancement is measured using the root-mean-square (RMS) parameter.

Landslide surveillance using a wireless measurement grid

This paper presents a wireless landslide measurement grid based on new type of transducers. Magnetic strain gauges are used as sensitive element for the transducer. Measurements regarding landslide displacement and orientation were done using strain gauges based on amorphous magnetic microwires (MAW). In order to identify small changes in the monitoring area, a grid of multiple measurement points is placed. Measurement nodes acquire modulus and direction of displacement vector reporting the data through serial communication to the central unit coordinator. A complex system that collects data from multiple locations is developed. Data is collected wirelessly by a central server. Evaluating the landslide acquired information, we have established a relationship between the system readings and the landslide movement.