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Medical Image Segmentation by Active Contour Improvement
Abdelaziz Essadike,
Elhoussaine Ouabida,
Abdenbi Bouzid
Issue:
Volume 6, Issue 2, April 2017
Pages:
13-17
Received:
13 March 2017
Accepted:
22 March 2017
Published:
3 April 2017
Abstract: This paper introduces a new medical image segmentation approach based on active contour improvement. The boundaries in brain images are detected using an original technique of active contour improved by a Region of Interest (ROI) extraction. We compare the results of the proposed model to Chane-Vese active contour model and Caselles’s et al. Geodesic active contour model. Experimental results of brain boundary localization on a national center of Oncology’s database demonstrate the promising performance of this method.
Abstract: This paper introduces a new medical image segmentation approach based on active contour improvement. The boundaries in brain images are detected using an original technique of active contour improved by a Region of Interest (ROI) extraction. We compare the results of the proposed model to Chane-Vese active contour model and Caselles’s et al. Geodes...
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An Online Poultry Diseases Monitoring System for Nigeria
Moses Oyekunle Oyetunji,
Florence Alaba Oladeji,
Olorunjube James Falana,
Peter Adebayo Idowu
Issue:
Volume 6, Issue 2, April 2017
Pages:
18-28
Received:
21 March 2017
Accepted:
31 March 2017
Published:
24 April 2017
Abstract: Poultry disease statistics in Nigeria reveal a serious and growing problem with absolute fatality rate and casualty figure rising rapidly. A crucial goal of infectious disease surveillance is the early detection of epidemics, which is essential for disease control. The current system for monitoring poultry disease is based on conventional method using extension workers and confirmed case reports which has proved ineffective over the years. The poultry disease monitoring system aimed at assisting poultry farmers, healthcare officers and stakeholders alike to understand the distribution of poultry diseases and the state of poultry farms in Nigeria in order to ensure early detection and response during an outbreak. The system requirement was elicited from poultry farmers located within the south-western part of Nigeria using interviews while the requirements were designed using use-case diagrams for the representing data insertion and data query. The system was implemented using HTML, PHP and CSS while the database was implemented using MYSQL. In conclusion, the use of monitoring system would be of great importance in providing accurate, timely and detailed information about poultry disease in Nigeria. It will also help to alert disease control agencies about poultry related diseases in Nigeria.
Abstract: Poultry disease statistics in Nigeria reveal a serious and growing problem with absolute fatality rate and casualty figure rising rapidly. A crucial goal of infectious disease surveillance is the early detection of epidemics, which is essential for disease control. The current system for monitoring poultry disease is based on conventional method us...
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Shibuya Method and Modified ITU Knife Edge Diffraction Loss Model for Computing N Knife Edge Diffraction Loss
Kalu Okore Ama,
Constance Kalu,
Aneke Chikezie
Issue:
Volume 6, Issue 2, April 2017
Pages:
29-34
Received:
3 January 2017
Accepted:
10 January 2017
Published:
12 June 2017
Abstract: In this paper, algorithm for applying Shibuya multiple knife edge diffraction method and modified ITU-R P 526-13 knife edge diffraction loss approximation model are presented. Particularly, in this paper, algorithm for using the two models for computing N knife edge diffraction loss is presented. Requisite mathematical expressions for the computations are first presented before the algorithm is presented. Then sample 10 knife edge obstructions are used to demonstrate the application of the algorithm for C-band 6 GHz microwave link. The results showed that for the 10 knife edge obstructions spread over a path the maximum virtual hop single knife edge diffraction loss is 14.97452dB and it occurred in virtual hop j =6 which has the highest diffraction parameter of 1.027072 and the highest line of site (LOS) clearance height of 8.480769m. The minimum virtual hop single knife edge diffraction loss is 7.881902 dB and it occurred in virtual hop j =9 which has the lowest diffraction parameter of 0.114761 as well as the lowest LOS clearance height of 0.628571m. The algorithm is useful for development of automated multiple knife edge diffraction loss system based on Shibuya method and the modified ITU-R P 526-13 knife edge diffraction loss approximation model.
Abstract: In this paper, algorithm for applying Shibuya multiple knife edge diffraction method and modified ITU-R P 526-13 knife edge diffraction loss approximation model are presented. Particularly, in this paper, algorithm for using the two models for computing N knife edge diffraction loss is presented. Requisite mathematical expressions for the computati...
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Determination of Rounded Edge Diffraction Loss for a Plateau Using Hacking Method
Victor Akpaiya Udom,
Kalu Constance,
Asuquo Ifiok Okon
Issue:
Volume 6, Issue 2, April 2017
Pages:
35-39
Received:
3 January 2017
Accepted:
18 January 2017
Published:
12 June 2017
Abstract: In this paper, Hacking rounded edge diffraction loss method is used to determine the diffraction loss over a plateau in the path of microwave signal in the GSM frequency band, 800 MHz to 2100 MHz. The computation is based on the path profile with path length of 4996.243 m and a plateau in the signal path. The plateau has maximum elevation of 268.9 m and it occurred at a distance of 3557.8 m from the transmitter. The line of sight clearance height is 45.747499 m and occultation distance is 1538.759 m. At 800 MHz, the diffraction loss is 55.25 dB whereas at 2100 MHz the diffraction loss is 71.713 dB. The result is useful for GSM network planning.
Abstract: In this paper, Hacking rounded edge diffraction loss method is used to determine the diffraction loss over a plateau in the path of microwave signal in the GSM frequency band, 800 MHz to 2100 MHz. The computation is based on the path profile with path length of 4996.243 m and a plateau in the signal path. The plateau has maximum elevation of 268.9 ...
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Algorithm for Computing N Knife Edge Diffraction Loss Using Epstein-Peterson Method
Wali Samuel,
Fidelis Osanebi Chucks Nwaduwa,
Trust Christopher Oguichen
Issue:
Volume 6, Issue 2, April 2017
Pages:
40-43
Received:
3 January 2017
Accepted:
18 January 2017
Published:
12 June 2017
Abstract: In this paper, algorithm for computing N knife edge diffraction loss using Epstein-Peterson method and International Telecommunication Union (ITU) knife edge diffraction loss approximation model is presented. Requisite mathematical expressions for the computations are first presented before the algorithm is presented. Then sample 10 knife edge obstructions are used to demonstrate the application of the algorithm for L-band 1 GHz microwave signal. The results showed that for the 10 knife edge obstructions spread over a path length of 36 km the maximum virtual hop single knife edge diffraction loss is 8.054711 dB and it occurred in virtual hop j =10 which has the highest diffraction parameter of 0.233333. However, the virtual hop j =10 has line of site (LOS) clearance height of 2.333333 m whereas the highest LOS clearance is 3.454545 m and it occurred in virtual hop j =6. The minimum virtual hop single knife edge diffraction loss is 6.109884 dB and it occurred in virtual hop j =3 which has the lowest diffraction parameter of 0.008909 as well as the lowest LOS clearance height of 0.142857 m. The algorithm is useful for development of automated multiple knife edge diffraction loss system based on Epstein-Peterson method and ITU knife edge diffraction loss approximation model.
Abstract: In this paper, algorithm for computing N knife edge diffraction loss using Epstein-Peterson method and International Telecommunication Union (ITU) knife edge diffraction loss approximation model is presented. Requisite mathematical expressions for the computations are first presented before the algorithm is presented. Then sample 10 knife edge obst...
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Determination of the Minimum Antenna Mast Height with Nonzero Path Inclination: Method II
Fidelis Osanebi Chucks Nwaduwa,
Wali Samuel,
Elsie Chidinma Anderson
Issue:
Volume 6, Issue 2, April 2017
Pages:
44-48
Received:
3 January 2017
Accepted:
18 January 2017
Published:
12 June 2017
Abstract: In this paper, a second method for the determination of the minimum antenna mast height for line of site wireless communication link with nonzero path inclination and with known height of one of the antennas is presented. In the first method,(not presented here), none of the antenna height is known. In this second paper, the height of one of the antenna is known, particularly, the antenna that is above the maximum obstruction height. This places further constraint in the determination of the minimum antenna mast height for the lower antenna. In this paper, both the mathematical models and the algorithm are presented along with sample numerical example using path profile data for a 3 GHz microwave communication link with path length of 38.8876 km. The know antenna height is 20 m above the maximum height of the tip of the obstruction which is found to be 146.62 m at a distance of 14306.98 m from the transmitter. From the result, the receiver antenna height is 166.6 m and transmitter antenna height is 135.35 m whereas, the transmitter antenna mast height is 45.51 m while the receiver antenna mast height is 117.1 m the path inclination is 0.804. The ideas presented in this paper are particularly useful when a line of sight link is to be extended from an existing transmitting point.
Abstract: In this paper, a second method for the determination of the minimum antenna mast height for line of site wireless communication link with nonzero path inclination and with known height of one of the antennas is presented. In the first method,(not presented here), none of the antenna height is known. In this second paper, the height of one of the an...
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Evaluation of the Effect of Radius of Curvature on the Rounded Edge Diffraction Loss Computed by Hacking Method for a Plateau
Swinton C. Nwokonko,
Ikechukwu H. Ezeh,
Vital K. Onwuzuruike
Issue:
Volume 6, Issue 2, April 2017
Pages:
49-55
Received:
8 January 2017
Accepted:
18 January 2017
Published:
12 June 2017
Abstract: In this paper, the effect of the radius of curvature on the diffraction loss of rounded edge obstruction is presented. The study is conducted for C-band microwave link with a plateau in its path. The plateau has flat to that spans about 1922 m. Two different approaches are used to determine the radius of curvature of the rounded edged fitted to the plateau top. Among the two methods employed, the ITU-R 526-13 method overestimated the radius (about 12,374,693.37 m) as against 59,031.42 m estimated by the second method at the same C-band frequency of 4 GHz. Also, high radius of curvature by the ITU-R 526-13 method gave very high diffraction loss value for the plateau. Furthermore, with the ITU-R 526-13 method, the radius of curvature does increase with increase in frequency. In all, the results indicate that the ITU-R 526-13 method is not particularly suitable for estimating the radius of curvature for the rounded edge when applied to a plateau. In addition, a more accurate method is required to estimate the radius of curvature for computing rounded edge diffraction loss.
Abstract: In this paper, the effect of the radius of curvature on the diffraction loss of rounded edge obstruction is presented. The study is conducted for C-band microwave link with a plateau in its path. The plateau has flat to that spans about 1922 m. Two different approaches are used to determine the radius of curvature of the rounded edged fitted to the...
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Determination of Diffraction Loss over Isolated Doubled Edged Hill Using the ITU-R P.526-13 Method for Rounded Edge Diffraction
Ogungbemi Emmanuel Oluropo,
Ikechukwu H. Ezeh,
Chibuzo Promise Nkwocha
Issue:
Volume 6, Issue 2, April 2017
Pages:
56-60
Received:
8 January 2017
Accepted:
18 January 2017
Published:
12 June 2017
Abstract: In this paper, Recommendation ITU-R P.526-13 rounded edge diffraction loss method is used to determine the diffraction loss over a double edged hilltop in the path of 6 GHz C-band microwave signal. The computation is based on the path profile with path length of 6188.665 m. The path profile has maximum elevation of 412.75 m and it occurred at a distance of 2877.3 m from the transmitter. The line of sight clearance height is 35.393521m and occultation distance is 532.203m. The diffraction loss computed for the double edged hilltop using the Recommendation ITU-R P.526-13 model is 42.563065 dB.
Abstract: In this paper, Recommendation ITU-R P.526-13 rounded edge diffraction loss method is used to determine the diffraction loss over a double edged hilltop in the path of 6 GHz C-band microwave signal. The computation is based on the path profile with path length of 6188.665 m. The path profile has maximum elevation of 412.75 m and it occurred at a dis...
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