The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper, we implement a passive optical network (PON) using coherent source spatial multiplexed spectral amplitude coding (SM SAC) optical code division multiple access (OCDMA) scheme. By applying spatial multiplexing it was possible to reduce the beat noise, which is the main limiting factor of performance in coherent source SAC OCDMA system, which will lead to high speed PONs. Results showed...
This paper presents a method to measure the forearm's subcutaneous veins depth by using the theory of light propagation model. In this study, we proposed a practical method to measure the forearm's vein deep by designed an optical phantom and experiment setup to measure the diffuse reflectance (Rd). The Monte Carlo Multilayer (MCML) tool had been used to simulate the light migration into skin layer...
Wireless Sensor Networks (WSNs) are vulnerable to clone attacks as they are deployed in hostile and unattended environtments. Also due to the lack of physical tamper-resistance, an adversary can easily capture and compromise sensor nodes and after replicating them, he inserts arbitrary number of clones into network. As a result the adversary is able to mount a wide variety of internal attacks. Several...
Venipuncture as a mode of gaining intravenous access is a crucial practice in pre-surgical and conventional drug administering procedures. Biomedical engineering has focused on the automation and aid in these processes to promote and encourage non-invasive catheterization of patients. Indeed, medical personnel are highly challenged by the various patient's skin tones and topologies. This paper proposes...
Blood vessels detection is a common task performed in numerous medical procedures. During regular medical treatments venipuncture procedures are performed for invasive medication and blood sampling. Near infrared imaging technology can be used to visualize the subcutaneous veins in cases of difficult venous access. In this paper the methods for veins centerline detection and back projection is presented...
Advance biomedical engineering technologies are continuously changing the medical practices to improve medical care of patients nowadays. In this paper, we describe the concept used to prototype a device for needle insertion navigation during intravenous catheterization process via Near Infrared (NIR) imaging technique. A vein locator prototype using the NIR imaging technique and augmented reality...
In the matter of detecting clone attacks, we bring in a novel solution called Single Stage Memory Random Walk with Network Division (SSRAND) to circumvent the problems of simple random walk as exploited by both RAND and RAWL protocols. SSRAND combines the single stage memory random walk with network division for clone detection and simulation results verify that it not only reduces the communication...
Intensity noise (IN) or phase induced intensity noise (PIIN) is the key limiting factor of the performance in spectral amplitude coding optical code division multiple access (SAC OCDMA) systems. The PIIN can be mitigated in SAC OCDMA by splitting the signals and detecting each signal by a different photodiode if the independence between the split signals can be achieved. In this paper, we derive the...
An end-coupled line bandpass filter (BPF) is proposed and designed by placing defected ground structure (DGS) in the ground plane. DGS is used for its property of miniaturizing the size of microwave filter and also improving the mutual coupling between the resonators. The proposed dumbbell shaped DGS is used to tune the bandpass filter to 2.4 GHz with dimension of 44 mm × 18 mm. A wide tuning range...
Wireless Sensor Networks are vulnerable to node replication attacks due to deployment in unattended environments and the lack of physical tamper-resistance. An adversary can easily capture and compromise sensor nodes and after replicating them, he inserts arbitrary number of replicas into the network to mount a wide variety of internal attacks. In this paper we propose a novel distributed solution...
A stepped impedance resonator bandpass filter (SIR BPF) is proposed and designed by placing defected ground structure (DGS) in the ground plane. DGS is used for its property of miniaturizing the size of microwave filter and also improving the mutual coupling between the resonators. The proposed dumbbell shaped DGS is used to tune the bandpass filter to 2.4 GHz with dimension of 28 mm × 30 mm. A wide...
In this paper we validate through software simulation that a Gamma probability density function (pdf) can give a very good approximation of the detected intensity of the incoherent light source. We performed two experiments, in the first experiment the pdf of 0.25 nm optical signal is measured for different photo detector's electrical bandwidth. In the second experiment the eye diagram reading is...
This paper evaluates the performance of spatial multiplexing (SM) in beat noise mitigation in coherent spectral amplitude coding (SAC) OCDMA via the Optisystem software kit. We take into consideration two different laser source configurations; a centralized shared multi laser source and a precisely controlled multi laser source. For different performance merits, the results showed superiority of the...
We propose the use of a divided spectrum balanced detection (DSBD) to reduce the intensity noise in spectral amplitude coding (SAC) OCDMA systems. Simulation results show several order of magnitude improvements in bit error rate (BER) compared to the conventional balanced detection.
Intravenous (IV) catheterization is the most important phase in medical practices of daily life. It is hard to localize veins in patients who have deep veins, minor age or dark skin; hence multiple attempts become indispensable for proper catheterization in such cases. Near Infrared (NIR) Imaging allow to visualize the veins underneath the skin of persons having non-visibility of veins problem. This...
Maintaining coverage-aware connectivity is extremely crucial for successful operation of mobile actor/robot networks as mobile nodes have to collaborate on the data received from sensors and perform coordinated action. However, failure of a critical node (i.e., cut vertex) may introduce a coverage hole besides partitioning the network into disjoint segments, and thus disrupts the operation. Most of...
Cooperative spectrum sensing (CSS) is capable to improve the performance of signal detection. It is one solution to overcome fading, shadowing, and uncertainty noises. Unlike centralized networks, Secondary User (SU) in decentralized networks independently senses license channel without forwarding the sensing result to central coordinator. This paper investigates the performance of Decentralized Multiuser...
Defected ground structures (DGS) have known to be serving for the improvement in characteristics of many microwave circuits. Not only DGS has various advantages in the area of microwave power amplifier, Wilkinson power divider, microwave antennas, couplers etc, it is also used in the design of microwave filter to achieve stopband effects, slow-wave effects, frequency adjustment etc. A bandpass filter...
In this paper, we study the performance of the multi photodiode balanced detection (MPBD) scheme in phase induced intensity noise (PIIN) reduction for spectral amplitude coding Optical code division multiple access (SAC OCDMA) systems, when the PIIN is assumed to have a Gamma distribution. The PIIN is signal dependent source of noise which increases with signal power. The MPBD reduces the optical...
To provide seamless internet connectivity anywhere at any time to the mobile users, there is a strong demand for the integration of wireless access networks for all-IP based Next Generation Networks (NGNs). The major limitation of UMTS networks is that they do not efficiently serve indoor, small and densely populated areas, i.e., hotspots. On the other hand, such hotspots where bandwidth intensive...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.