Effective maintenance enabled by the use of witness simulation in a Libyan cement factory
Conference paper

This paper presents a new approach using Witness Simulation in combating issues related to maintenance within the existing manufacturing facility. Currently, maintenance is a key issue as many machines breakdown due to every day wear and tear as well as the age of the machine itself. This causes bottlenecks within the entire production system as the schedules of production is disturbed and further backlogs are developed. Also, when machines breakdown there seems to be very little communication from one end to another ie parts are needed for the repair of many of the machines, for example, it is very common for the rotary kiln to come to a halt due to increased temperature and different quantities of a mixture of materials. In order to fix the problem and move back on schedule the maintenance team uses certain materials ie same materials, all the time. However, due to not having an adequate stock control system and the lack of communication many a times, parts are not readily available and hence the team wait further until parts arrive at the facility. This paper will demonstrate how all of the above problem areas can be adhered to via the use of adopting a simple automated response system using Witness Simulation. The demonstration will be based on a single machine for testing purposes to ensure efficiency that can later be applied to the entire system as a whole.

Elbahlul Mussa Alghadafi Abogrean, (01-2012), International Journal of Advances in Management and Economics: International Journal of Advances in Management and Economics, 138-147

Application of the Bayesian network to machine breakdowns using witness simulation
Conference paper

This paper explores the use of Bayesian network modeling of machine breakdowns within a cement manufacturing plant. The Bayesian network modeling is introduced using Hugin software and then implemented into a Witness Simulation model using historical data, expert knowledge and opinions. The models simulate 3 parameters of the machine based on life consumption and usage of each parameter, the developed Witness model produces a probability failure rate based on these parameter usages. The failure probability developed by Witness is implemented using the Chain Rule; this is compared with the probability for failure based on the Bayesian network model. This enables the user to see the probability of failure developed by the implementation of the chain rule and Witness based on the parameter usage, on a live streaming fashion as the model is running. This can be used as a decision making tool for management to consider machine maintenance affectively based on parameter usage.

Elbahlul Mussa Alghadafi Abogrean, (01-2012), Proceedings of the World Congress on Engineering: Proceedings of the World Congress on Engineering, 1-6

Stochastic Simulation of Machine Breakdowns
Journal Article

This paper explores the value of stochastic simulation as a tool for predicting current or future reliability of machinery, it helps to understand machine failures by using confidence levels developed through replications and exploring the changes that occur. A stochastic simulation model has been constructed representing a crusher machine with in a cement manufacturing plant. The crusher machine has three parameters; namely those are drill head, dusting and lubrication. The consumption of these parameters results in the development of a probability of failure for the machine using Bayes theory.

Elbahlul M. Alghadafi Abogrean, (01-2012), Macrothink Institute: Journal of Public Administration and Governance, 1 (2), 95-104

Synthesis of marine Derived 3-alkylpyridinium alkaloids with potent antiprotozoal activity
Journal Article

Given the pressing need for new antiprotozoal drugs without cross-resistance with current (failing) chemotherapy, we have explored 3-tridecylpyridinium alkaloids (3TPAs), derivatives of viscosamine, as antiparasitic agents. We have developed a simple synthetic route toward viscosamine and related cyclic and linear monomers and oligomers. Evaluation for cytotoxicity on the protozoan parasites Trypanosoma brucei, Leishmania spp., and Plasmodium falciparum revealed several 3TPAs with antiprotozoal activity in the nanomolar range. Their promising selectivity index in vitro prompted us to study the dynamics of cytotoxicity on trypanosomes in more detail. Parasites were killed relatively slowly at therapeutically safe concentrations, in a process that did not target the cell cycle. Clearance of T. brucei cultures was observed at drug concentrations of 1–10 μM.

Juma Ahmed Mohamed Ali, (10-2011), United States of America: American Chemical Society medicinal chemistry letters Medicinal chemistry letters, 12 (2), 901-906

Properties enhancement of Al-Zn-Mg alloy by retrogression and re-aging heat treatment
Journal Article

The higher strength 7xxx aluminum alloys exhibited low resistance to stress corrosion cracking (SCC) when aged to the peak hardness (T6 temper). The overaged alloys (T7 temper) developed to enhance the SCC with loss in the strength of the alloy. Recently, retrogression and re-aging (RRA) heat treatments are used for improving the SCC behavior for alloys in T6 tempers such as 7075, 7475 and 8090. In this study, an application of retrogression and re-aging heat treatment processes are carried out to enhance toughness properties of the 7079-T651 aluminum alloy, while maintaining the higher strength of T651-temper. The results of charpy impact energy and electrical conductivity tests show a significantly increases in absorbed energy and electrical conductivity values, when the alloys are exposed to various retrogression temperatures (190, 200, 210°C) and times (20, 40, 60 minutes), and then re-aged at 160°C for 18 hours.

Hassan Ramadan Faraj Zaid, (10-2011), Belgrade-Serbia: Journal Of Mining and Metallurgy, 47 (1), 31-35

EXISTENCE OF POSITIVE CONTINUOUS SOLUTION OF A QUADRATIC INTEGRAL EQUATION OF FRACTIONAL ORDERS
Journal Article

We are concerned here with the existence of at least one positive

continuous solution of the quadratic integral equation of fractional orders

x(t) = a(t) + Iαf(t; x(t)) · Iβg(t; x(t)); α; β 2 (0; 1]:

The maximal and minimal solutions are also proved. Some applications are

given.

Fatma Farag Said Omar, , A. M. A. EL-SAYED, , M. SH. MOHAMED, (07-2011), Journal of Fractional Calculus and Applications: تم أختياره, 9 (1), 1-7

New Approach of Encrypting Embedded Data in H.264 Compressed Video
Journal Article

Digital video steganography has attracted a great deal of research interest in the recent few years in applications. In this paper, we propose a method to embed and encrypt messages into video sequences by using steganography technique Based on the H.264 video coding standard. The system implemented in this work provides robust H.264 video compression constant, without significantly affecting the overall bit rate and quality of the video stream. The results indicate that the algorithm can be implemented steganography fast and efficiently and effect vision and peak signal to noise ratio (PSNR) of video sequences are almost unaffected after decoding.

Tarik Idbeaa, (05-2011), Trans Tech Publications, Switzerland: Advanced Materials Research, 1 (230), 346-351

The Efficiency of Data Hiding by Manipulating the DPCM Macroblocks in Compressed Video
Journal Article

Steganography is the idea of embedding a secret data in different media and has become an important regulation of methods of data integration. Although the still images are generally applied in the past, is very popular in recent years for the video. The techniques of video data hiding in recent year’s emphasis on the features generated by the video compression standard, a safer method for steganography uses MPEG-4/H.264 Bit Plane Complexity Segmentation (BPCS) algorithm is proposed in this approach. The reason for choosing such a video coverage is the enormous amount of data that can be hidden in each frame of MPEG-4 video. In other words, MPEG-4 has three types of images: I-frame, B, and P frames. Unlike other techniques used to hide data, such as the LSB algorithm, PBCS can achieve better results in both mathematics expression and human vision. In this paper, data is embedded in the videos of the I-frame until the BPCS can reach high levels of integration with low distortion based on the theory that regions of low noise-levels as in a picture can be replaced by noise without a significant loss of image quality. This approach invents data hidden in high-security environments. Experimental results show the success of hidden data in the selected and extracted data from the sequence of frames and also indicate the effectiveness of the implementation plan of steganography compressed video with high security features.

Tarik Idbeaa, (05-2011), Trans Tech Publications, Switzerland: Advanced Materials Research, 1 (230), 69-74

Conserved, Highly Specialized Olfactory Receptor Neurons for Food Compounds in 2 Congeneric Scarab Beetles, Pachnoda interrupta and Pachnoda marginata
Journal Article

Few studies have systematically addressed evolutionary changes in olfactory neuron assemblies, either by genetic drift or as an

adaptation to specific odor environments. We have studied the sense of olfaction in 2 congeneric scarab beetles, Pachnoda

interrupta Olivier and Pachnoda marginata Drury (Coleoptera: Scarabaeidae: Cetoniinae), which are both opportunistic

polyphages, feeding mainly on fruit and flowers. The 2 species occur in dissimilar habitats: P. interrupta is found in dry

savannah, and P. marginata in tropical parts of equatorial Africa. To study how these species may have adapted their sense of

olfaction to their odor environments, we utilized single-unit electrophysiology on olfactory sensilla with a wide selection of

food-related compounds. Despite the differences in habitat, we found that the species shared most of the physiological types

of olfactory receptor neurons (ORNs) encountered, although their proportions frequently varied between the species. The high

degree of conservation in olfaction between the species implies that a similar sensory strategy is efficient for food search in

both habitats. However, shifts in proportions of receptor neuron classes, and slight shifts in response profiles and/or presence

of some ORN classes unique to either species, may reflect adaptation to a different set of hosts.

Key words: comparative study, electrophysiology, olfaction, polyphagous herbivore, single sensillum recordings

Hamida Shaban Omar Khbaish, (03-2011), Chem. Senses: Chem. Senses, -36 (36), 499-513

• بحث بعنوان " جيومورفولوجية الجبل الغربي" مجلة الجمعية الجغرافية الليبية – الزاوية، العدد الأول، 2009م.
مقال في مجلة علمية


نوري أبوفائد احمد العيساوي، (01-2011)، جامعة طرابلس: مجلة الفكر، 1 (1)، 294-317

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