Noise uncertainty effect on multi-channel cognitive radio networks

Achieving high throughput is the most important goal of cognitive radio networks. The main process in cognitive radio is spectrum sensing that targets getting vacant channels. There are many sensing methods like matched filter, feature detection, interference temperature and energy detection which is employed in the proposed system; however, energy detection suffers from noise uncertainty. In this paper a study of throughput under noise fluctuation effect is introduced. The work in this paper proposes multi-channel system; the overall multi-channel throughput is studied under noise fluctuation effect. In addition, the proficiency of the network has been examined under different number of channels and sensing time with noise uncertainty

Karakteristik Bakteri Pereduksi Merkuri (Escherichia Coli) Diisolasi dari Perairan Pantai Teluk Manado

In the environment like seawater, mercury can be oxidized by some bacteria, such as Thiobacillus, to produce Hg ions which are soluble in water and toxic to marine organisms, such as bacteria, algae, and so on. On the other hand, the occurrence of Pseudomonas, as E. coli, is believed can reduce the number of Hg ions in the environment. An experiment was conducted to count total coliform and total E. coli, to isolate, to identify E. coli isolated from Manado Bay seawater, and to determine the ability of E. coli isolates to do reduction and or oxidation of mercury ions. Seawater samples were collected from the reclamation area, especially close to Tondano River, Sario River and Bahu River around Manado Bay. As a control, some water samples were taken from Bunaken Island waters at Liang and Muka Kampung area. An amount of 500 ml water samples was taken from the sampling site and placed into container, then brought to the laboratory for further analysis, such as total coliform, total E. coli. In addition, some biochemical tests were also carried out in order to identify the isolate. The results showed that nearly all isolates of E. coli (83.3%) exhibited their ability in mercury ions oxidation, while the isolates that can reduce ion mercury were 13.3% only. The highest Hg-ions reduction was influenced by the characteristic of isolates, and mercury ions oxidation was also dependent upon the strain type

Teacher characteristics and effective teaching among secondary school teachers in calabar education zone, cross river state nigeria

The study examined the influence of teacher characteristics (teacher qualification and year of teaching experience) on effective teaching among secondary school social studies teachers in Calabar education zone of Cross River State Nigeria. To achieve this objective, two hypotheses were formulated and tested. The survey research design was adopted for the study. The sample consist of One hundred and sixty-four (164) teachers in sixty (60) secondary schools in the zone. One structured questionnaire titled “Teacher Characteristics and Effective Teaching Questionnaire’’ (TCETQ) was developed by the researcher and validated by experts in Sociology of Education and in measurement/Evaluation, it had a reliability coefficient of .75 & .92 developed using split half reliability method. One-way analysis of variance (ANOVA) was the statistical tool used to test the hypotheses at 0.05 level of significance. The result of the analysis revealed that teachers’ qualification and year of experience significantly influence effective teaching. Based on the findings, it was recommended among others that teachers should be encouraged to frequently go for professional development long and short term courses in order to acquire knowledge that can facilitate delivery and those who have spent more years should see the need to give room for mentor-mentee relationship for the betterment of the system. &nbsp

The Application Concentration Addition of Skim Milk to Soy Milk Kefir

Soy milk is a product processed soybean extract that resembles cow's milk. High protein content makes soy milk as highly nutritious vegetable milk. But the beany flavor of the resulting lead soy milk consumption levels are relatively low. One way of improving the quality of soy milk with a probiotic drink that process into soy milk kefir. The purpose of this study to determine the effect of the concentration of skim milk to soy milk kefir quality, namely in terms of the physical and chemical properties, microbiological and organoleptic. The study was conducted in two stages: determining the length of fermentation and then proceed with the manufacture of soy milk with the addition of different concentrations of skim milk of four treatments that control, the addition of skim milk concentration 0%, 4% and 8%. This research using completely randomized design (CRD). The result showed the addition of skim milk concentration effect on total of bacteria acid lactic (BAL), total yeast, colour, and flavor of soy milk kefir. The addition of skim milk concentration causes an increase in total BAL, total yeast and pH. For organoleptic show that the colour and flavor of soy milk kefir with a concentration of 8% skim milk is preferred compared with the three other treatments

Komposisi Kimia, Senyawa Bioaktif Dan Ankga Lempeng Total Pada Rumput Laut Gracillaria Edulis

This study was conducted to determine the proximate composition, bioactive compound and total plate count (TPC) in Gracilaria edulis seaweed. This research used descriptive explorative method. The results showed the average value of moisture content (77.7%); protein content (39.4%); fat content (8.1%); carbohydrates by difference (71.7%); ash content (20.7%) and very low bacterial count. Phytochemical test results show this seaweed contains alkaloids, saponins, flavonoids, and triterpenoids compounds. Penelitian ini dilakukan untuk mengetahui komposisi proksimat, senyawa bioaktif dan angka lempeng total (ALT) pada rumput laut Gracilaria edulis. Penelitian ini menggunakan metode penelitian deskriptif eksploratif. Hasil penelitian menunjukkan nilai rata-rata kadar air (77,7%); protein (39,4%); kadar lemak (8,1%); karbohidrat (71,7%); kadar abu (20,7%) dan jumlah bakteri yang sangat rendah. Hasil uji fitokimia menunjukkan rumput laut ini mengandung senyawa alkaloid, saponin, flavonoid, dan triterpenoid

Demographic factors and teachers’ effectiveness among secondary school teachers in calabar education zone cross river state, nigeria

The article aims to discuss teaching effectiveness in relation to teacher demographic factors like teachers’ age and teachers’ gender among Secondary School teachers in Calabar Education Zone of Cross River State, Nigeria. To achieve this aim, two hypotheses were stated and tested. These variables have important role to evaluate teachers’ effectiveness as scholarly proven through literatures. The descriptive survey design was adopted for use. The sample consist of one hundred and sixty-four (164) teachers and three hundred and twenty-eight (328) student from the Calabar Education Zone. Teachers’ Demographic Factors Questionnaire (TDFQ) and Teaching Effectiveness Questionnaire (TEQ) were developed by the researcher and validated by experts in Sociology of Education and Test/Measurement. The descriptive statistics, one-way analysis of variance, a post-hoc scheffe & independent t-test were used. The result revealed that teachers’ age and gender significantly influence teaching effectiveness. Based on the findings, it is recommended among others that Government should see teachers age as an asset thereby put in more resources to train them so that they will be of benefit to the students and the society at large

Profile of Mangrove Ecosystem in Bahoi Village North Minahasa Regency

This study was carried out in mangrove forest of Bahoi, Likupang district, North Minahasa regency. It was aimed at knowing the ecological condition of the mangrove forest. Study stations were selected by determining representatives from each zonation and site condition. Results showed that mangrove species in Bahoi was dominated by Rhizophora mucronata, R. apiculata, Bruguiera gymnorrhiza, B. cylindrical, and Sonneratia alba, with the highest density in station 1 shown by Rhizophora apiculata, 0.65 ind/m2, then station 2 and 3 by R. Mucronata, 0.93 and 0,63 ind/m2, respectively. The highest total density was recorded in station 2, 1.85 ind/40 m2, then station 1, 1.78 ind/40 m2, and station 3, 1.35 ind/40 m2, respectively. As conclusion, the ecological condition of mangrove ecosystem in Bahoi was categorized as good, and aware to be beneficial for the local community in ecological function as abrasion prevention and living environment of the aquatic biota and in economic function from ecotourism aspect, so that it was right to be managed in the form of ecotourism management

Profil Ekosistem Mangrove Di Desa BAHOI Kabupaten Minahasa Utara (Profile of Mangrove Ecosystem in Bahoi Village North Minahasa Regency)

This study was carried out in mangrove forest of Bahoi, Likupang district, North Minahasa regency. It was aimed at knowing the ecological condition of the mangrove forest. Study stations were selected by determining representatives from each zonation and site condition. Results showed that mangrove species in Bahoi was dominated by Rhizophora mucronata, R. apiculata, Bruguiera gymnorrhiza, B. cylindrical, and Sonneratia alba, with the highest density in station 1 shown by Rhizophora apiculata, 0.65 ind/m2, then station 2 and 3 by R. Mucronata, 0.93 and 0,63 ind/m2, respectively. The highest total density was recorded in station 2, 1.85 ind/40 m2, then station 1, 1.78 ind/40 m2, and station 3, 1.35 ind/40 m2, respectively. As conclusion, the ecological condition of mangrove ecosystem in Bahoi was categorized as good, and aware to be beneficial for the local community in ecological function as abrasion prevention and living environment of the aquatic biota and in economic function from ecotourism aspect, so that it was right to be managed in the form of ecotourism management