Performance Analysis of Best Relaying Protocol Selection with Interferences at Relays

In this paper, we investigate the performance of selecting the best protocol between amplify and forward (AF) and decode and forward (DF) in multiple relay networks with multiple interferences at relays. In the selection scheme, the best protocol between AF and DF is selected depending on the comparisons of signal-to-interference and noise ratio (SINR) for all source-relay links. All relays measure the received SINR to decide forwarding signal or not. When SINR is above a certain threshold then DF is used otherwise AF is used. Particularly, we develop an accurate mathematical model for best relaying protocol by considering the effect of interferences to our scheme. Firstly, we derive the asymptotic closed form expression for the symbol error rate (SER) for the system under study. Also we derive an upper and lower bound of symbol error rate and show how they were tight with exact SER. Furthermore an approximate expression for the outage probability is derived. Numerical results are finally presented to validate the theoretical analysis with a different number of relays

PERBEDAAN UKURAN SERO TANCAP TERHADAP HASIL TANGKAPAN DI PERAIRAN KAITETU, MALUKU TENGAH

Sero tancap merupakan alat tangkap tradisional terbuat dari bambu dan kayu. Alat tangkap sero tancap tergolong dalam trap dengan memanfaatkan tingkah laku ikan yaitu feeding migration, spawning migration  dan hal-hal lain seperti adanya periode pasang surut. Sero tancap pada kondisi perairan seperti di depan ekosistem mangrove, padang lamun, terumbu karang, dan perairan pesisir memiliki topografi dan isodepth yang khas. Perbedaan ukuran sero dan karaketeristik perairan mengindikasikan perbedaan hasil tangkapan. Tujuan Penelitian untuk mengetahui karakteristik kedalaman perairan diareal sero tancap dan perbedaan hasil tangkapan di Perairan Kaitetu. Pengukuran kedalaman perairan di areal kedua sero dengan metode zig zag dengan menggunakan perahu motor tempel setiap 30 detik dengan memotret data kedalaman (feet) dan posisi pada display fish finder dan GPS. Selanjutnya dianalisis dengan menggunakan software surfer 8 berbasis Windows untuk membuat kontur isodepth. Perbedaan hasil tangkapan digunakan analisis non parametric (Uji Kruskal Wallis). Hasil penelitian menujukkan bahwa perbedaan dimensi ukuran sero tancap disebabkan karena isodepth lebih berhimpit pada areal pemasangan sero tancap 2 yang lebih kecil ukurannya pada kedalaman  5-10 meter daripada sero tancap 1 pada kedalaman 0-10 meter. Hasil uji Kruskal Wallis menunjukkan tidak terdapat perbedaan hasil tangkapan pada kedua sero tancap

Modelling relationship between rainfall variability and millet (Pennisetum americanum L.) and sorghum (Sorghum bicolor L. Moench.) yields in the Sudan savanna ecological zone of Nigeria

This study models the relationship between rainfall variability parameters and millet (Pennisetum americanum L.) and sorghum (Sorghum bicolor L. Moench.) yields in the Sudan Savanna ecological zone of Nigeria. Daily rainfall data recorded by the nearby stations for the period between 1981 and 2010 as well as millet and sorghum yield data were used as inputs in the model. It attempts to develop model for predicting millet and sorghum yields based on rainfall variables. The analytical tools used in developing and testing the model performance include ogive of cumulative pentad rainfall, product-moment correlation coefficient (r), stepwise multiple regression analysis and coefficient of determination (R2). The study produced four yield forecast models; three for millet at Kano, Katsina and Potiskum and the last for sorghum at Potiskum. Model accounted for 61.7% of variation in millet yield due to total annual rainfall and 68.1% in sorghum yield due to total rainfall in may assume the best-fitted yield forecast models. The unaccounted variation of 38.3% in millet yield and 31.9% in sorghum indicate other factors could influence the yield variability of the two crops. It is recommended that based on holding annual and may totals rainfall constant, the two best-fitted crop yield models should be used for planning and forecasting the yield of millet and sorghum in the study area. Key words: modelling, rainfall, yields, millet, sorghu

TINGKAH LAKU IKAN BUBARA (Caranx ignobilis) TERHADAP LAMA WAKTU PERENDAMAN UMPAN

Umpan merupakan faktor penting pada perikanan pancing. Pemahaman tingkah laku dan respon makan ikan menjadi bagian penting untuk mengetahui efektivitas penggunaan umpan. Tujuan penelitian yaitu mendeskripsikani pola reaksi ikan kuwe (C ignobilis) terhadap perlakuan umpan, dan menganalisis pengaruh lama waktu perendaman umpan dan waktu pengamatan terhadap respon C ignobilis. Penelitian dilakukan dengan metode percobaan. Umpan yang digunakan adalah potongan daging ikan cakalang. Sampel ikan C ignobilis sebanyak 5 ekor (TL 29-30 cm). Data penelitian meliputi waktu respons makan ikan terhadap umpan masing-masing adalah umpan tidak di rendam, umpan direndam 1 jam dan (C) umpan direndam 2 jam yang dilakukan secara acak pada pagi hari (jam 07.30-09.30) dan malam hari (jam 21.00-23.00). Hasil penelitian menunjukkan bahwa ada tiga fase dalam proses C ignobilis memangsa umpan meliputi fase appearance, approach, dan attack. Respons makan C ignobilis terhadap potongan umpan cakalang secara parsial pada pagi hari dan malam hari tidak berbeda (P>0,05). Terdapat perbedaan respons makan C ignobilis lebih cepat pada kondisi waktu pagi hari dibandingkan pada malam hari (P<0,05)

Evaluation of different feeding frequencies on growth performance and feed utilization of Clarias gariepinus (Burchell, 1822). Fingerlings

The experiment was conducted to assess the growth performance and feed utilization of Clarias gariepinus under the feeding frequencies of T1 (twice/day), T2 (thrice/day), and T3 (four times/day) at 3% BWD per day over a period of 56 days. A total of 180 fingerlings with average weight of 2.39±0.19g and average length of 5.02±1.04cm were stocked at 15 fish per plastic container of 35 litres capacity. The highest weight gain recorded at the end of the experiment was 7.39±0.19g in (T3) and the lowest was 5.35±0.31g in (T1). The highest specific growth rate (SGR%) value of 1.19±0.02 was recorded in (T3) and the lowest 1.01±0.03 was recorded in (T1). T3 recorded the highest FCR value of 1.88±1.37, while the lowest value of 8.34±2.12 was obtained in (T1). Therefore, Treatment 3 yielded the best performance in terms of WG, SGR, and FCR and can be recommended for enhanced growth performance and optimum feed utilization.Keywords; Fingerlings, feeding, frequency, growth, performance, utilization

Assessment of Nutritional Status and Knowledge of Students from Selected Secondary Schools in Sokoto Metropolis, Sokoto State, Nigeria

The significance of improving nutrition knowledge in order to have a positive influence on food choices and health should not be underestimated. This study assessed the nutritional status and knowledge of school children attending selected secondary schools in Sokoto metropolis. The study population was purposively drawn from secondary school students in Nigeria attending Federal Government College and State Government-owned schools. Four secondary schools were used for the study: Federal Government College (FGC), Sani Dingyadi Secondary School (SDUSS), Nagarta Secondary School (NSS) and Army Day Secondary School (ADSS). A sample of 240 school students, aged 10 to 25 years participated in the study. The measuring instruments included a questionnaire to determine the nutrition knowledge of the students. Anthropometric measurements included weight, height and mid-upper arm circumference, measured using standard methodologies. The mean age recorded for male and female students were 18.0±1.90 and 15.7±1.20 years, respectively. The result showed that 27.9% were underweight, 7.5% overweight and 64.6% had normal BMI status. Nutritional status was significantly related with sex (χ2 = 16.169, p<0.05) but not with age (χ2 = 1.368, p>0.05). The prevalence of underweight was higher among the males (33.9%) compared to the females (13.9%), while more females were overweight (15.3%) compared to the males (4.2%). Seventy one percent performed poorly in the nutrition knowledge assessment rating. The overall performance of the female students was significantly higher (χ2 = 46.386; P<0.05) than their male counterparts. Furthermore, 5, 12 and 12% had excellent, very good and good nutrition knowledge, respectively, while 33% and 38% had fair and poor nutrition knowledge, respectively. The results further revealed that the students were deficient in knowledge and understanding of the facts about energy and nutritive values of foods. Therefore, adequate nutrition education is needed at the secondary school level; this will enable the students to make good food choices and positively influence their eating habits thereby ensuring better nutritional status.Keywords: malnutrition, knowledge, school, anthropometry, Sokot

Evaluation of Sheanut Shell-Reinforced Automotive Brake Pad

For over a century now, asbestos has been used as friction material in the manufacture of brake pads but its use is currently been avoided due to its carcinogenic nature and potential to cause cancer. This study is focused on development of a new brake pad using sheanut shell (SNS) which is an eco-friendly material as the reinforcement and epoxy resin as the binder. Other constituents used are calcium carbonate (CaCO3), graphite and aluminium oxide (Al2O3). Five compositions were formulated with the epoxy resin and reinforcement varied at interval of 5 wt% while CaCO3, graphite and Al2O3 remain constant at 30, 10 and 10 wt% respectively. The developed brake pads were subjected to compressive, abrasive and water absorption tests while their densities were also measured. The results showed that the compressive strength, abrasive strength and the density of the samples decreased as the reinforcement content increased while the water absorption rate increased as the reinforcement content increased. The value of the compressive strength ranged from 64.88 – 93.04Mpa, wear rate from 3.13 – 6.25mg/m, water absorption from 0.899 – 2.722% and density from 0.764 – 1.487g/m3. The result of this research indicates that SNS particles can be used as a replacement for asbestos in brake pad production

Prevalence of malaria and geohelminth co-infection among antenatal women at the Federal Medical Centre and Specialist Hospital, Yola, Adamawa Sate, Nigeria

Malaria and geohelminths are known to be associated with pregnancy within all age groups. The objective of this study was to determine the prevalence of malaria and geohelminths co-infection among pregnant women. The study was conducted on 252 pregnant women who came for antenatal visits at Federal Medical Center and Specialist Hospital within Yola metropolis from July to November 2015. Socio-demographic information of the pregnant women was collected. Capillary blood from finger prick was used for malaria screening by microscopy. Geohelminths were determined by stool examination using wet mount and formal ether concentration techniques. Malaria, geohelminths and co-infecion had 20.2%, 21.4%, and 6.3% prevalence, respectively. Those within 20-24 and 25-29year age group had high rate of coinfection of 2.4% each. The results show no association between age and coinfection p<0.05. Malaria was significant in this study at p<0.05. The result show relatively low rate of coinfection of malaria and geohelminths prevalence.Keywords: Prevalence, Malaria, Geohelminths, Coinfection, Hospital, Yol

Physical properties of the Schur complement of local covariance matrices

General properties of global covariance matrices representing bipartite Gaussian states can be decomposed into properties of local covariance matrices and their Schur complements. We demonstrate that given a bipartite Gaussian state $\rho_{12}$ described by a $4\times 4$ covariance matrix \textbf{V}, the Schur complement of a local covariance submatrix $\textbf{V}_1$ of it can be interpreted as a new covariance matrix representing a Gaussian operator of party 1 conditioned to local parity measurements on party 2. The connection with a partial parity measurement over a bipartite quantum state and the determination of the reduced Wigner function is given and an operational process of parity measurement is developed. Generalization of this procedure to a $n$-partite Gaussian state is given and it is demonstrated that the $n-1$ system state conditioned to a partial parity projection is given by a covariance matrix such as its $2 \times 2$ block elements are Schur complements of special local matrices.Comment: 10 pages. Replaced with final published versio

Negative imaginary theorem with an application to robust control of a crane system

This paper presents an integral sliding mode (ISM) control for a case of negative imaginary (NI) systems. A gantry crane system (GCS) is considered in this work. ISM is a nonlinear control method introducing significant properties of precision, robustness, stress-free tuning and implementation. The GCS model considered in this work is derived based on the x direction and sway motion of the payload. The GCS is a negative imaginary (NI) system with a single pole at the origin. ISM consist of two blocks; the inner block made up of a pole placement controller (NI controller), designed using linear matrix inequality for robustness and outer block made up of sliding mode control to reject disturbances. The ISM is designed to control position tracking and anti-swing payload motion. The robustness of the control scheme is tested with an input disturbance of a sine wave signal. The simulation results show the effectiveness of the control scheme