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Benefits of EM technology in animal production
No full textBenefits of EM technology in animal productio
فوائد الزبادي
No full textفوائد الزباديعديد من الفوائد الطبيعية الصحية الهامة الموجودة في هذا الغذاء الخفيف واللذيذ وماخفي اعظم حتي إن العلماء باتو يعتقدون انه غذاء المستقب
الممـــيزات التشريحـــية للإبــــل
No full textالممـــيزات التشريحـــية للإبــــلكل هذه الصفات جعلت من الابل حيوان مميز قادر علي التاقلم مع بيئته القاسية ، محور هذه الاعضاء عن طريق سلوك معين ووظائف مختلفه تعينه علي البقاءعلي مر الدهور .
فهل يستطيع الإبل الاستمرار في مقاومة الظروف البيئية مستقبلا
الاســــــتــــــنـــــسـاخ
No full textالاســــــتــــــنـــــسـاخويتضح مما سبق إن التقدم العلمي في مجال استخدام التكنولوجيا الحيوية في التناسل يخطو خطوات واسعة يوما بعد يوم بهدف الوصول إلي أقصر وقت إلي زيادة الحيوانات الممتازة وراثيا لضمان الحصول منها علي أقصي إنتاجية ممكنة بأقل أعداد من الحيوانات مقارنة بالوسائل التقليدية المستخدمة في التحسين الوراثي كالانتخاب الوراث
MAINTENANCE AND CONTROL OF AN INDUSTRIAL ROBOT SERIES UNIMATE 2300
No full textOne of the great objectives of this project is to build a connection line between the
university and the important Industrial corporations in the Sudan. The project also
aims to get use of the unused robots by first applying all experiments and tests on one
of them; if the tests succeed they can be generalized to other robots. There is another
special aim of the project is that it provides a good chance to deal with work
environment.In 1997 the management of an industrial complex bought six industrial robots to be
used for carrying heavy loads on its various factories. They were secondhand and no
body knows how to operate them. Great efforts were done by the complex
maintenance engineers to repair these robots by contacting the manufacturer.
Unfortunately they made in USA, by UNIMATE Company and for politic reasons the
connection was cut.
The problem was to study how they work; it was a problem because there was only
one source for information, the attached manual. In addition to the manual you must
take a course in UNIMATE institute to be able to just operate the robot and carryout
the periodic maintenance. So, to repair the original system or change it you will face
many difficulties, starting from the spare parts until the required software.
Therefore, from the beginning our opinion was to change the old control system, in
spite of that we try to repair the old system but we failed.
The next step was to focus our efforts on operating the robot manually, new problems
appear here, the type and amount of the input signal and to which terminals it must be
supplied .All the work was done on one robot and we succeeded in operating it. A
manual control panel was designed
Finally a general design is introduced to the new control system in which we use the
microcontroller. We introduce both the structure of the new system and the algorithm
which can be used to program the microcontroller
Relaying Protocols
No full textthe project is Design code for amplify and forward Design code for decode and forward and Compare between above two method mentioned at the receiver side in message or simply signal to noise ratio (S/N) with different values of noise.Relay system can be described as node between source and destination processed received signal from source by enhancing it and forward it to destination. Numbers of relays systems in a path of signal depend on distance between source and destination and effect of that channel in signal. Relay system used in it different methods each method contains advantages and disadvantages, in this project used one relay system and methods used in it are amplify and forward (AF) which amplify digital signal received from source with specific gain and forward it to destination to demodulate it to get message without modulation, and the other method was decode and forward (DF) which demodulate the received signal from source and again modulate it and it forwarded to destination to do as before. Main goal of this project is to compare between above two methods which is better to reduce effect of channel more than other since this effect can't completely remove. Results of this compare have a great importance since these methods are equipment and it cost money so by know behavior of these methods against noise power money can be saved. Main goal of project achieved and results appear that method of decode and forward is better than method of amplify and forward for small values of noise power and at high values of noise power method of amplify and forward is better than method of decode and forward
LIGHTING AND EARTHING DESIGN ACCORDING TO IEEE80_2000 AND IEC 62305-2
No full textthe project objective to
1. Developing lightning risk assessment software to help the user assess the risk due
to all possible effects of lightning strikes to structures according to the risk
management method reported in IEC 62305-2.
2. Developing an effective design tool according to IEEE 80-2000 standard to help
designers model and build grounding systems that will ensure the performance of
power systems and safety of personnel.. Lightning is one of the most beautiful displays in nature but it can have
devastating results. Lightning can kill people, destroy properties and cause millions of
dollars of damage. Thus protection against this phenomenon is crucial for avoiding
such loss.
Absolute protection against lightning is impossible but through deployment
of a judicious combination of defenses, the lightning protection engineer can attempt
to mitigate the lightning consequences. The need for protection, the economic benefits
of installing protection measures and the selection of adequate protection measures
should be determined in terms of risk management.
The IEC 62305-2 standard presents a procedure to assess the risk due to all
possible effects of lightning flashes to structures. The risk management procedure
described in IEC 62305-2 is rather complicated. It would be useful for lightning
protection engineers to have a software tool to carry out this risk assessment.
The purpose of substation grounding/earthing is to protect the equipment from
efeect of short circite and surges and lightning strikes and to protect the operating
persons in the substation. The substation earthing system is necessary for connecting
neutral points of transformers and generators to ground and also for connecting the
non current carrying metal parts such as structures, overhead shielding wires, tanks,
frames, etc. to earth. Earthing of surge is through the earthing system.
In this project we developed two software tools. One to perform the tedious
risk assessment as described in IEC 62305-2. The other is to assess the safety of the
ground grid design as described in IEEE80-2000 standard. Both of them were
developed using visual basic and they were proved to be reliable and intuitiv
SSL VPN Performance Evaluation
No full textThis project is to design SSL VPN between two computers using open
source called Openvpn and evaluate its performance, to give this more secure solution
good advance to replace most currently used solution IPsec VPN. We have been
successfully developed and implement our design and the performance of this SSL VPN
has been successfully tested.Virtual Private Networks (VPN) have become of increasing interest as technique to
connect remote networks and users, this interesting is exist by economic perspective
since the leased lines is not suitable solution economically to connect two far networks or
support remote access to network resources and where the internet access is spread
allover the world . However the VPN must secure enough since we use internet, which is
open to all users ,make it easy to hack private data so we must using high security
protocols , most recently VPN use IPsec tunneling protocol to give need security and
privacy to intranet and extranet VPN ,but is it the best solution ? A Secure Socket Layer
protocol is introduced to be new solution, but is SSL VPN degrades or increases the
network performance?
This gives rise to the need for studies about SSL VPN to know the effects of the
encryption of data and tunneling headers added to data be suitable for VPN on the
performance measures like transfer rate, throughput, jitter, packet loss and etc.
The purpose of this project is to design SSL VPN between two computers using open
source called Openvpn and evaluate its performance, to give this more secure solution
good advance to replace most currently used solution IPsec VPN. We have been
successfully developed and implement our design and the performance of this SSL VPN
has been successfully tested.
It‟s found that in general the performance is not effected or effects is not noted with
changing of encryption algorithm (each encryption algorithms has a different key size),
except when measure include the header bits added for tunneling (tunneling: making
VPN packet suitable with internet) like transfer rate and data access time of file which
degraded with large key sizes e.g. AES key size (256 bit). Also there is a big difference in
performance between encrypted data and unencrypted data.
And also as good edition to the project we make a simple test to measure RTT and
throughput on IPsec VPN give high values in RTT as suggested (around 7.24 ms)
WIRELESS ELECTRICAL ENERGY TRANSFER
No full textThis project discusses the possibility of
transferring electrical energy over mid-range distance
without wires ( wirelessly).This project discusses the possibility of
transferring electrical energy over mid-range distance
without wires ( wirelessly) , a theoretical and
numerical model is presented and it shows that via
Strongly Coupled Magnetic Resonances , wireless
power transfer can be achieved efficientl
Routing in multi-hop ad hoc networks
No full textThe objective of this project is to study and compare the performance of three routing
protocols for mobile ad hoc network environments. These three routing protocols which
are being investigated are Ad Hoc On-demand Distance Vector routing (AODV),
Dynamic Source Routing (DSR) and Destination-Sequenced Distance-Vector routing
(DSDV). The performance analysis will focus on network overhead, packet delivery ratio
in addition to average end to end communication delay.Ad-hoc networking is a concept in computer communications, which means that users wanting to communicate with each other form a temporary network, without any form of centralized administration. Each node participating in the network acts both as host and a router and must therefore to be willing to forward packets for other nodes. For this purpose, a routing protocol is needed.
An ad-hoc network has certain characteristics, which imposes new demands on the routing protocol. The most important characteristic is the dynamic topology, which is a consequence of node mobility. Nodes can change position quite frequently, which means that we need a routing protocol that quickly adapts to topology changes. The nodes in an ad-hoc network can consist of laptops and personal digital assistants and are often very limited in resources such as CPU capacity, storage capacity, battery power and bandwidth. This means that the routing protocol should try to minimize control traffic, such as periodic update messages
In this project three (3) such routing protocols were chosen for analysis and evaluation: Ad Hoc On-demand Distance Vector routing (AODV), Dynamic Source Routing (DSR) and Destination-Sequenced Distance Vector routing (DSDV).
Network simulator (NS-2) was used to simulate these protocols. The key performance indicators of the routing protocols were analyzed such as routing overhead generation, data delivery delay as well as packet delivery ratio. The mobility model considered in this project namely, Random Waypoint, can be applicable to networks such as conferences, shopping center, and emergency situations with people walking as nodes.
The performance of the routing protocols in varied mobility speed as well as loading conditions has been studied.
The results of the simulation provided valuable insights to the performance of the selected routing protocols. It gave a clear demonstration of the features of the three studied protocols. It show that in high mobility, the on-demand routing protocols perform better than the chosen proactive protocol DSDV. However, the results also indicate that in low mobility DSDV performs equally as good as reactive protocols