વિજ્ઞાન અને ટેકનોલોજિના અધયાપન માટે કમ્પ્યૂટર એઈડેડ ઇન્સ્ટ્રકશન (CAD) કાર્યક્રમ, વર્કકાર્ડ અને જૂથ અધ્યાપન પધ્ધતિની અસરકારકતા

આજના યુગને માહિતી અને પ્રત્યાપનના યુગથી ઓળખાય છે. જીવનના તમામ ક્ષેત્રે પહેલાં કરતાં વધુ માહિતી પ્રાપ્ય બની છે. આની અસર શિક્ષણના ક્ષેત્રે પણ જોવા મળે છે. શિક્ષણની પ્રક્રિયામાં વિદ્યાર્થી જેટલો સક્રિય રહે તેટલું અધ્યયન તેજસ્વી અને અસરકારક બને છે અને વિદ્યાર્થીની આંતરિક શક્તિ વિકસે છે. સ્વ-અધ્યયનની જુદી-જુદી પ્રયુક્તિઓ વિદ્યાર્થીઓમાં રહેલા વૈયક્તિક તફાવતોને ધ્યાનમાં રાખીને સ્વ-ગતિએ આગળ વધવાની પ્રેરણા પૂરી પાડે છે. વિજ્ઞાન અને ટેકનોલોજિ એવો વિષય છે કે જેમાં શિક્ષણને વધુ રસપ્રદ બનાવવા માટે વિવિધ શૈક્ષણિક સાધનો અને પધ્ધતિઓનો ઉપયોગ થઈ શકે છે. પ્રયોજક પ્રાણીશાસ્ત્રના અનુસ્નાતક હોવાથી આ વિષય પ્રત્યે વધુ લગાવ હોય એ સ્વાભાવિક છે. શિક્ષણને વધુ રસપ્રદ બનાવવા તેમજ વિદ્યાર્થીઓ સ્વ-ગતિએ આગળ વધે એ માટે કમ્પ્યૂટર એઈડેડ ઇન્સ્ટ્રકશન (CAD) કાર્યક્રમ, વર્કકાર્ડ અને જૂથ અધ્યાપનની અસરકારકતા શૈક્ષણિક સિધ્ધિના સંદર્ભમાં ચકાસવા પ્રસ્તુત અભ્યાસ હાથ ધર્યો હતો

PCA based components selection criteria for computationally efficient Physical Layer Key Generation (PLKG) system

Data security is one of the prime concerns in wireless networks. PLKG has been emerging as an attractive alternative to traditional cryptographic techniques. PLKG is more computationally efficient than cryptography. Moreover, PLKG using Principal component analysis (PCA) as pre-processing may further save computations. This paper proposes three mechanisms to select components of PCA which are based on Information content, Mean and Histfit. Bit Disagreement Rate (BDR) is compared for each mechanism. Histfit based method is found to be best. Since only two components are supposed to be processed for key generation, it is computationally efficient/ power efficient too

PCA Based Components Selection Criteria for Computationally Efficient Physical Layer Key Generation (PLKG) System

Data security is one of the prime concerns in wireless networks. PLKG has been emerging as an attractive alternative to traditional cryptographic techniques. PLKG is more computationally efficient than cryptography. Moreover, PLKG using Principal component analysis (PCA) as pre-processing may further save computations. This paper proposes three mechanisms to select components of PCA which are based on Information content, Mean and Histfit. Bit Disagreement Rate (BDR) is compared for each mechanism. Histfit based method is found to be best. Since only two components are supposed to be processed for key generation, it is computationally efficient/ power efficient too

Collision Resolution Schemes with Nonoverlapped Contention Slots for Heterogeneous and Homogeneous WLANs

CSMA/CA-based DCF of 802.11 MAC layer employs a best-effort delivery model, in which stations compete for channel access with the same priority. In a heterogeneous network, providing different priorities to different applications for required quality of service is a challenging task, since heterogeneous conditions result in unfairness among stations and degradation in the throughput. This paper proposes a class of collision resolution schemes for 802.11 having contention window control with nonoverlapped contention slots. In the first scheme, window ranges of two consecutive stages are nonoverlapped, and it is called nonoverlapped contention slots (NOCS) scheme. In the other scheme, termed as NOCS-offset, an offset is introduced between window ranges of two stages. Selection of a random value by a station for its contention with discontinuous distribution results in reduced probability of collision. Analytical and simulation results show that the proposed scheme exhibits higher throughput and fairness with reduced delay and collision probability in homogeneous and heterogeneous networks. Performance of the proposed scheme is evaluated for mix traffic and high data rate environment with advanced back-off management techniques to meet the requirements of the present applications

Collision Resolution Schemes with Nonoverlapped Contention Slots for Heterogeneous and Homogeneous WLANs

CSMA/CA-based DCF of 802.11 MAC layer employs a best-effort delivery model, in which stations compete for channel access with the same priority. In a heterogeneous network, providing different priorities to different applications for required quality of service is a challenging task, since heterogeneous conditions result in unfairness among stations and degradation in the throughput. This paper proposes a class of collision resolution schemes for 802.11 having contention window control with nonoverlapped contention slots. In the first scheme, window ranges of two consecutive stages are nonoverlapped, and it is called nonoverlapped contention slots (NOCS) scheme. In the other scheme, termed as NOCS-offset, an offset is introduced between window ranges of two stages. Selection of a random value by a station for its contention with discontinuous distribution results in reduced probability of collision. Analytical and simulation results show that the proposed scheme exhibits higher throughput and fairness with reduced delay and collision probability in homogeneous and heterogeneous networks. Performance of the proposed scheme is evaluated for mix traffic and high data rate environment with advanced back-off management techniques to meet the requirements of the present applications

Energy Efficient Rate Adaptation Algorithm for FiWi Access Network

Abstract Similar to any telecommunication network, energy efficiency is a desirable feature for fiber wireless (FiWi) access networks. These networks have optical back end and wireless front end. Both ends may contribute for energy efficiency. This work focuses on front end of FiWi access network, which is IEEE 802.11a wireless local area network (WLAN). For energy saving WLAN uses power saving mode (PSM), in which sleeping opportunity of a station is increased. During sleep time, station remains switched off and results in reduction in energy required. However, it is also observed that during active period of transmission considerable energy is consumed, which is the function of rate of data transmission. More data rate results in more active energy consumption but less transmission delay and vice versa. In order to reduce active and hence total energy consumption, we tried to transmit the data at lower data rate, while maintaining transmission delay in tolerable limit. This paper presents an Energy Efficient Rate Adaptation Algorithm (EERAA) for the front end of fiber wireless access networks. Simulation results compare the energy efficiency and transmission delay of EERAA and various existing fixed data rate schemes. Proposed scheme offers good trade-off between energy efficiency and transmission delay

Computation of Various QoS Parameters for FiWi Access Network

AbstractFiber wireless (FiWi) access network is one of the broad band access networks used to support multimedia applications and interactive services. However minimum QoS needs to be maintained by the network. In this paper a method has been proposed to compute the various network parameters such as packet delivery ratio (PDR), average delay and network throughput for a FiWi network, to ensure minimum QoS. This approach may be proved very useful in computing these parameters comprehensively for any algorithm related with research issues of FiWi network like ONU placement, survivability, energy efficient algorithms etc