Performance of the Public Electric Power Industry: Evidence from Pakistan

The study investigates the performance of electric power sector of Pakistan at the firm level, as well as the sector as a whole. It identifies and attempts to quantify the extent of inefficiencies. Since either physical or financial or productivity indicators alone are not able to explain the duality of public infrastructure purposes and the complexity of their multi-dimensional goals, a set of relevant physical, financial, and productivity indicators have been used in evaluating the performance of this sector. Further, a Cobb- Douglas production function has also been used to calculate the trend in the growth of total factor productivity. Economies of scale have also been studied in the case of electric power generation.

Cooperative subcarrier sensing using antenna diversity based weighted virtual sub clustering

The idea of cooperation and the clustering amongst cognitive radios (CRs) has recently been focus of attention of research community, owing to its potential to improve performance of spectrum sensing (SS) schemes. This focus has led to the paradigm of cluster based cooperative spectrum sensing (CBCSS). In perspective of high date rate 4th generation wireless systems, which are characterized by orthogonal frequency division multiplexing (OFDM) and spatial diversity, there is a need to devise effective SS strategies. A novel CBCSS scheme is proposed for OFDM subcarrier detection in order to enable the non-contiguous OFDM (NC-OFDM) at the physical layer of CRs for efficient utilization of spectrum holes. Proposed scheme is based on the energy detection in MIMO CR network, using equal gain combiner as diversity combining technique, hard combining (AND, OR and Majority) rule as data fusion technique and antenna diversity based weighted clustering as virtual sub clustering algorithm. Results of proposed CBCSS are compared with conventional CBCSS scheme for AND, OR and Majority data fusion rules. Moreover the effects of antenna diversity, cooperation and cooperating clusters are also discussed

Sustainability Of Markhor Trophy Hunting Programme In District Kohistan Pakistan

Trophy hunting is a form of sport hunting that has been practiced since hunting gatherer period. Usually, animals hunted as trophies have large weapons such as horns, antlers or tusks. Therefore, trophy animals are mostly males, and the animals most frequently considered as trophy species are ungulates. In 1983 the Wildlife Department of the Khyber Pakhtunkhwa province in Pakistan began the Chitral Conservation Hunting Programme, a trophy hunting programme for makhor (Capra falconeri cashmiriensis). Pemburuan trofi merupakan suatu bentuk sukan pemburuan yang diamalkan sejak berzaman lamanya. Biasanya, haiwan yang diburu sebagai trofi mempunyai tanduk atau gading, dan kebanyakannya adalah jantan. Pada tahun 1983, Jabatan Hidupan Liar Khyber, Wilayah Pakhtunkhwa, Pakistan memulakan Chitral Conservation Hunting Programme, iaitu suatu program pemburuan trofi bagi markhor (Capra falconeri cashmiriensis)

Peak to average power ratio based spatial spectrum sensing for cognitive radio systems

The recent convergence of wireless standards for incorporation of spatial dimension in wireless systems has made spatial spectrum sensing based on Peak to Average Power Ratio (PAPR) of the received signal, a promising approach. This added dimension is principally exploited for stream multiplexing, user multiplexing and spatial diversity. Considering such a wireless environment for primary users, we propose an algorithm for spectrum sensing by secondary users which are also equipped with multiple antennas. The proposed spatial spectrum sensing algorithm is based on the PAPR of the spatially received signals. Simulation results show the improved performance once the information regarding spatial diversity of the primary users is incorporated in the proposed algorithm. Moreover, through simulations a better performance is achieved by using different diversity schemes and different parameters like sensing time and scanning interval

Cluster-based cooperative subcarrier sensing using antenna diversity-based weighted data fusion

Cooperative spectrum sensing (CSS) is used in cognitive radio (CR) networks to improve the spectrum sensing performance in shadow fading environments. Moreover, clustering in CR networks is used to reduce reporting time and bandwidth overhead during CSS. Thus, cluster-based cooperative spectrum sensing (CBCSS) has manifested satisfactory spectrum sensing results in harsh environments under processing constraints. On the other hand, the antenna diversity of multiple input multiple output CR systems can be exploited to further improve the spectrum sensing performance. This paper presents the CBCSS performance in a CR network which is comprised of single- as well as multiple-antenna CR systems. We give theoretical analysis of CBCSS for orthogonal frequency division multiplexing signal sensing and propose a novel fusion scheme at the fusion center which takes into account the receiver antenna diversity of the CRs present in the network. We introduce the concept of weighted data fusion in which the sensing results of different CRs are weighted proportional to the number of receiving antennas they are equipped with. Thus, the receiver diversity is used to the advantage of improving spectrum sensing performance in a CR cluster. Simulation results show that the proposed scheme outperforms the conventional CBCSS scheme

Bayesian compressive sensing framework for spectrum reconstruction in Rayleigh fading channels

Compressive sensing (CS) is a novel digital signal processing technique that has found great interest in many applications including communication theory and wireless communications. In wireless communications, CS is particularly suitable for its application in the area of spectrum sensing for cognitive radios, where the complete spectrum under observation, with many spectral holes, can be modeled as a sparse wide-band signal in the frequency domain. Considering the initial works performed to exploit the benefits of Bayesian CS in spectrum sensing, the fading characteristic of wireless communications has not been considered yet to a great extent, although it is an inherent feature for all sorts of wireless communications and it must be considered for the design of any practically viable wireless system. In this paper, we extend the Bayesian CS framework for the recovery of a sparse signal, whose nonzero coefficients follow a Rayleigh distribution. It is then demonstrated via simulations that mean square error significantly improves when appropriate prior distribution is used for the faded signal coefficients and thus, in turns, the spectrum reconstruction improves. Different parameters of the system model, e.g., sparsity level and number of measurements, are then varied to show the consistency of the results for different cases

Peak to average power ratio reduction in NC–OFDM systems

Non contiguous orthogonal frequency division multiplexing (NC-OFDM) is an efficient and adaptable multicarrier modulation scheme to be used in cognitive radio communications. However like OFDM, NC-OFDM also suffers from the main drawback of high peak to average power ratio (PAPR). In this paper PAPR has been reduced by employing three different trigonometric transforms. Discrete cosine transform (DCT), discrete sine transform (DST) and fractional fourier transform (FRFT) has been combined with conventional selected level mapping (SLM) technique to reduce the PAPR of both OFDM and NC-OFDM based systems. The method combines all the transforms with SLM in different ways. Transforms DCT, DST and FRFT have been applied before the SLM block or inside the SLM block before IFFT. Simulation results show the comparative analysis of all the transforms using SLM in case of both OFDM and NC-OFDM based systems

Katma değer vergisinin kuzey kıbrıs ekonomisi üzerine etkisi: kısa dönem değerlendirmesi

Value added tax was introduced in North Cyprus in 1996 to increase public revenue as well as to harmonize with Turkey and EU member countries. It is however evident that the budget deficit has rather increased after the introduction of VAT. The literature argues that VAT not only has potential to generate enough revenue to reduce the budget deficit but also encourages savings and investments. The question is why could North Cyprus not achieve these objectives? The present study was designed to answer this question. It evaluates the impact of VAT on the North Cyprus economy by using several macroeconomic variables such as total consumption, total domestic savings, public, private and total investments, government purchases, exports and imports. The impact of VAT has been studied through simple regression techniques with dummy variable for policy change.Gerek kamu gelirlerinin artırılması, gerekse Türkiye ile AB’ye üye ülkeler ile uyumun sağlanması amacıyla, 1996 yılında Kuzey Kıbrıs’ta KDV uygulaması başlatılmıştır. Ancak, bu uygulama sonrasında, diğer bir deyişle KDV uygulamasından sonra dahi, bütçe açığında artış gözlenmiştir. Literatür araştırmalarından da ortaya konduğu üzere, KDV yalnızca bütçe açığını azaltacak düzeyde bir gelir artışı sağlamakla kalmayıp, aynı zamanda gerek tasarrufu gerekse yatırımları teşvik etmektedir. Bu konuda akla gelen soru ise, Kuzey Kıbrıs’ta neden bu hedeflere ulaşılamadığıdır. Mevcut çalışma ise, bu soruya bir yanıt almak üzere tasarlanmıştır. Yine bu bağlamda, anılan çalışma toplam tüketim, toplam tasarruflar, kamu, özel ve toplam yatırımlar, kamu alımları, ihracat ve ithalat gibi çeşitli makro ekonomik değişkenleri kullanarak KDV’nin Kuzey Kıbrıs ekonomisi üzerindeki etkilerini değerlendirmektedir. Böylece, KDV’nin etkisi politika değişimi için dummy değişken içeren basit regresyon tekniği ile incelenmiştir