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Structure, Coordination, Sensing and Allocation in Cognitive Radio Vanets

Thesis Info

Access Option

External Link

Author

Shahid Hussain Abbassi

Program

PhD

Institute

Air University

City

Islamabad

Province

Islamabad.

Country

Pakistan

Thesis Completing Year

2016

Thesis Completion Status

Completed

Subject

Applied Sciences

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/7543/1/Shahid_Hussain_Abbassi_Electrical_Eng_HSR_2016_Air_Univ_09.08.2016.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727249965

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With the increase in population, vehicle traffic has also increased on roads. This has caused an increase in accidents, due to which thousands of people lose their lives and millions get injured annually. Hence, a foolproof and secure Vehicular Ad-hoc Network (VANET) structure is required to reduce the number of accidents considerably. Pre-danger information must be communicated in real-time, in order to implement preventive measures to avoid accidents. VANETs are specially designed in order to communicate information about hazards. The protocol DSRC/WAVE/IEEE802.11p is proposed for VANETs, but it may not be enough to cope with increasing network traffic, especially emergency messages. Hence the use of cognitive Radio (CR) technology has been introduced. A lot of methods for coordination and channel allocation in the context of VANETs are being introduced. As such, the need of a framework to reliably compare the relative performances of different channel sensing, allocation and coordination schemes which take into account the movement of vehicles is felt. Different techniques like Independent Spectrum sensing and various forms of Cooperative techniques have been proposed in the near past. In this dissertation, a VANET structure has been proposed for highways and urban environments. In the Highway model, separate Road Side Units have been provided for the traffic on each side. In this way group formation for localized traffic will be easy on highways. Simulation results show that by using the proposed model, average throughput and end-to-end delay have improved considerably, while packet loss has also been reduced. We also propose an efficient spectrum sensing mechanism for sensing and sharing the CR spectrum by mobile vehicles, which combines best of stand-alone sensing and cooperative sensing techniques. The proposed mechanism not only improves the probability of correct detection, but also almost eliminates the probability of misdetection. Then we have introduced a framework that can be used to define and compare such schemes in a variety of scenarios. Simulation results clearly show the robustness of our technique by almost eliminating the misdetections and reducing to a great extent the false alarms. Afterwards we have proposed a sensing technique which prepares a database for small road segments, time slots for the hours of the day and different frequencies of the spectrum based on the sensing of vehicles throughout the day. Based on this database, the future utilization of the spectrum is proposed. Simulations and results clearly indicate the success and usefulness of our proposed technique. In the end we have proposed a model based on fuzzy logic for the allocation of different types of TV channels having different ON/OFF timings in different hours of the day taking time, vehicle speed, message priority and CR channel sensing results as input. The simulations performed show the utilization of every type of channel in speed versus time and message priority versus time. These results can be utilized well for the allocation patterns of CR channels.
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زلزلہ اور ہم

زلزلہ اور ہم
نحمدہ ونصلی علی رسولہ الکریم امّا بعد فاعوذ بااللہ من الشیطن الرجیم
بسم اللہ الرحمن الرحیم
صدرِذی وقار اور میرے ہم مکتب ساتھیو!
آج مجھے جس موضوع پر لب کشائی کرنی ہے وہ ہے:’’زلزلہ اور ہم‘‘
موضوع بہت طویل ہے اور وقت قلیل ، لیکن مجھے اس مختصر سے وقت میں مذکور ہ عنوان پر اپنے خیالات کا اظہار کرنا ہے۔
معزز سامعین!
زلزلے کے بارے میں مختلف قوموں کے مختلف نظریات ہیں یونانی قوم میں زلزلے کے بارے میں یہ تصور تھا کہ یہ عظیم سمندری اشتعال کا نتیجہ ہوتے ہیں ،میکسیکن ، و یکیورس ، کیلی فورنیا کے قبائل کا عقیدہ تھا کہ ایل ڈیبلو نامی انڈین خدا نے زمین کے ایک بڑے خطے کو کاٹ کر اپنے لئے مختص کر لیا، منگولیا چین کے باسیوں کا عقیدہ تھا کہ بڑے مینڈک نے اپنی پیٹھ پر دنیا کو اُٹھایا ہوا ہے جب وقتاًفوقتاً مینڈک اپنے جسم کو حرکت دیتا ہے تو زلزلے آتے ہیں، سائنس کا نقطہ نظر یہ ہے کہ ہزاروں بلکہ لاکھوں سال سے جاری زمین کے اندر مختلف قسم کی تبدیلیاں ، سمندری چٹانوں کی توڑ پھوڑ فالٹ کی صورت اختیار کر جاتی ہیں زمین کی تین سطحوں میں سے پہلی سطح کرسٹ ، دوسری مینٹل اور تیسری کور کہلاتی ہے۔ مینٹل سیمی لیکوڈ ہوتی ہے، کرسٹ اس پر تیرتی ہے جب کہ کورز مین کا درمیانی حصہ ہوتا ہے جب اندرونی چٹانیں ٹوٹتی ہیں تو ان تبدیلیوں سے پیدا ہونے والے دباؤ کو یہ غیر متوقع انداز میں خارج کرتی ہیں تو اس کی وجہ سے زمین کی اندرونی تہوں میں اضطرابی تخریب پیدا ہو جاتی ہے بعض اوقات کوئی ایک تہہ اس دباؤ کی وجہ سے ٹوٹ بھی جاتی ہے اور زمین کی بالائی سطح پرخارج شدہ توانائی شد ید جھٹکوں کا باعث بنتی...

Psychosocial Nurturing of Children in Islam

Psychosocial nurturing of children is linked with Parenting and personality development theories and child development theories too report evidences of influences of parenting on children nurturing. The purpose of this paper is to explore existing parenting styles in current literature and how these parenting styles influence upon and form the personality of the children in their early years. The paper aims to examine parenting with reference to authoritarian parenting, authoritative parenting, permissive parenting and uninvolved parenting. It discussed the expectations and responsiveness of the parents which determine their behavior and style. Through parenting, psychosocial nurturing of the children is determined and it was explained in existing literature and analyzed in Islamic teachings. The study followed a critical interpretivist method which examined the literature and conducted content analysis. The study examines the parenting concept and parenting style in Islamic teachings. Islam lays special emphasis on communication and attitude of the parents towards their children particularly in early childhood. Parenting style in Islamic teaching displays a loving and guiding mode. It is less demanding and more responsive in early years. Parenting in Islamic teaching encourages developing tolerance, harmony and peace. It shows flexibility to accept children’s dispositions and tries to discipline their inner faculties. Islamic teachings expect from parents to be responsive with love and passion. It gives children freedom to talk, walk, think and act in a carefree environment where they can become socially and emotionally strong. Parenting in Islam accepts children’s interests and attitudes with positive responses and respects their rights with warmth and love. It particularly develops moral awareness so that children can distinguish between right and wrong and also understand that they need to abide by rules and regulations. Lastly literature also reports that parenting in Islam does not allow any sort of harassment, coercion, frightening and unjust environment for the little angels.

An Investigation in to the Causes of Slow Diffusion of Tube Well Irrigation Technology in Nwfp-Pakistan

Irrigation is one of the most important ingredients of the Green Revolution technology, which took place in early 70’s. With out irrigation water, desirable results, of the new agricultural technology cannot be achieved. NWFP is mainly a mountainous region and its agriculture is characterized by low yield per unit and poor application of required inputs. About 54% of the total cultivated land still depends on rainfall which is scantly. Keeping in view the wide scope and importance of irrigation for enhancing agricultural output the present study was initiated. The study aims to analyze the existing situation of tube well irrigation and to pinpoint the main causes of slow diffusion of tube well technology in NWFP. Moreover, an attempt was also made to examine the role of extension agent in the adoption and diffusion of tube well technology. This study was based on primary as well as secondary data. The universe of the study consisted of the whole NWFP. Multistage sampling method was used to select a required sample, from four districts randomly selected. The number of respondents interviewed from district Charsada were 92, from DIK 70, from Malakand 68, and 61 respondents from district Nowshera, hence the total sample size was 291. The selected respondents were grouped into three categories namely small (146), medium (81) and large (64). The average size of land holding was 8 acres for small, 16 for medium and 92 acres for large farmers. Fragmentation seriously constrained tube well installation in the study area. The rate of tube well installation was less than 10 per year on average, thus there is clear justification and wide scope for future expansion if tube wells in the study area. Tube well irrigation not only enhances agricultural productivity, but socio-economic condition of the farmers was also improved. The role of government and NGO’s remained insignificant, because 288 respondents installed tube wells by themselves. The soil of the study area was found suitable for tube well installation. Moreover, water table was cost effective for the respondents in the study area. The discharge capacity of tube wells in the study area ranged from 2” to 4”. Majority of the respondents (96%) did not test the quality of water and soil. The overwhelming majority of the respondents (266) could not get loan. Extension services were heavily criticized and their role in the adoption and diffusion was negligible. The linkages among farmers, extension workers, and research institutes remained weak and poor. Small farmers were more prone to operational problems. The main operational problems were lack of spare parts, shortage of power, lack of skilled labour, and frequent load shedding of electricity. Almost all the sample respondents reported inadequate and untimely availability of inputs. The main factors responsible for late adoption and slow diffusion of tube well technology are; size of land holding, poor financial condition, lack of technical know how, topography, lack of power supply (electricity/diesel), inefficient and ineffective extension staff, imperfect market and policy negligence of the government. As a policy matter farmers (particularly small farmers) need to be encouraged to install tube wells, through the provision of soft loans and technical assistance.