Optimalisasi Jaringan Wireless Menggunakan Quality of Serfice (QoS) dan Algoritma Hierarchical Token Bucket (HTB)

Masalah kualitas layanan menjadi salah satu aspek penting dari sebuah jaringan computer. Pada jaringan di laboratorium riset UAD ditemukan beberapa masalah antara lain lambat nya kecepatan browsing, tetapi ada juga mahasiswa yang lancar dan cepat sekali ketika melakukan browsing. Pengaturan bandwidth masih menggunakan antrian FIFO. Berdasarkan permasalahan  tersebut, perlu dibangun sistem yang dapat memberikan kualitas layanan yang baik, dengan tetap meminimalisir penggunaan bandwidth. Tahapan dalam penelitian ini terbagi menjadi beberapa langkah yang terdiri dari pengumpulan data, analisis kondisi saat ini, perancangan arsitektur firewall, implementasi, pengujian dan rekomendasi. Tahapan pembangunan sistem terdiri dari perancangan topologi jaringan yang digunakan, konfigurasi awal jaringan yang meliputi konfigurasi interfaces, dhcp server, Ip Forwarding, NAT, DNS dan konfigurasi hotspot, perancangan Quality of Service (QoS) menggunakan metode Hierarchical Token Bucket (HTB). Pengujian sistem dilakukan dengan uji kelayakan pada saat sebelum dan sesudah diterapkannya metode Hierarchical Token Bucket (HTB) . Pengujian yang dilakukan pada sistem ini menggunakan uji kelayakan pada keadaan sebelum dan sesudah diterapkannya sistem. Adapun dari hasil data yang didapat adalah Throughput 128Kb/s kategori bagus, Delay 50 m/s kategori sangat bagus, Packet loss 2% kategori sangat bagus dan Jitter 6,4 sangat bagus. Kesimpulan yang didapat dari hasil pengujian bahwa penerapan Quality of Service (QoS) dan Hierarchical Token Bucket (HTB) mampu memberikan kualitas layanan yang baik dan pemakaian bandwidth sesuai dengan pengaturan yang di tetapkan, sehingga mengurangi pemborosan bandwidth

Prediction of heat transfer performance of CuO/water nanofluids flow in spirally corrugated helically coiled heat exchanger using fuzzy logic technique

This paper presents the fuzzy logic expert system (FLES) for heat transfer performance investigation in helically coiled heat exchanger with spirally corrugated wall operated with water and CuO/water nanofluids. Compared with traditional logic model, fuzzy logic is more efficient in connecting the multiple units to a single output and is invaluable supplements to classical hard computing techniques. Hence, the main objective of this analysis is to investigate the relationship between heat exchanger working parameters and performance characteristics, and to determine how fuzzy logic expert system plays a significant role in prediction of heat transfer performance. Analytical values are taken in helically coiled heat exchanger with spirally corrugated wall operated with water and CuO/water nanofluids for investigation of heat transfer performance. The heat transfer coefficients of CuO/water nanofluids significantly increased about 5.90-14.24 with the increase of volume concentrations compared to water and while the values of the friction factor decreased with the increase in volume flow rate and volume concentration by using nanofluid instead of water. A fuzzy logic expert system model has developed for the prediction of heat transfer coefficient and friction factor. Verification of the developed fuzzy logic model was carried out through various numerical error criteria. For all parameters, the relative error of predicted values are found to be less than and/or slightly above the acceptable limit (5). The goodnesses of fit of the prediction values from the fuzzy logic expert system model are found to be close to 1.0 as expected, and hence demonstrated the good performance of the developed system. © 2014 Elsevier Ltd

Toxoplasmosis: prevalence and risk factors

A total of 200 pregnant women were recruited in this cross-sectional study. The overall seroprevalence of toxoplasmosis in pregnant women was found to be 49, in which 39, 4 and 6 for anti-Toxoplasma IgG, IgM and both anti-Toxoplasma IgG and IgM antibodies, respectively. We found the differences in Toxoplasma seroprevalence rates among the races were significant: the highest rate was in the Malays (55.7), followed by the Indian (55.3) and the Chinese (19.4) (-0.05) populations. An increase in Toxoplasma seroprevalence with increasing parity was detected (-0.05). Women with no children had a prevalence of 39.7, while women with one or more than two children had a prevalence of 44.2 and 62.9, respectively. In this study, there was no significant association between Toxoplasma seroprevalence and various possible risk factors in pregnant women (P�>�0.05). When multivariate analysis was performed, no significant association between Toxoplasma seroprevalence and history of contact with cats, consumption of undercooked meat and blood transfusion was found (P�>�0.05). We did not find any newly diagnosed cases of acute acquired toxoplasmosis in pregnancy during the study period. Read More: http://informahealthcare.com/doi/abs/10.1080/0144361031000160437

Toxoplasmosis: prevalence and risk factors

The gene encoding the excretory-secretory antigen TES-120 of dog ascarid worm Toxocara canis was cloned into the bacterium Escherichia coli. The specificity of the recombinant TES- 120 antigen produced by the bacterium was investigated.A total of 45 human serum samples from patients infected with different helminthes and protozoa, including 8 cases of toxocariasis, were tested against the recombinant antigens in immunoblot assays. The results from the assays revealed that the recombinant TES-120 antigen reacted with sera from toxocariasis patients only. This highly specific recombinant TES-120 antigen can potentially be used for the development of an inexpensive serodiagnostic assay for human toxocariasis

Preliminary Studies on Antimicrobial Activity of Extracts from Aloe Vera Leaf, Citrus Hystrix Leaf, Zingiber Officinale and Sabah Snake Grass Against Bacillus Subtilis

Herbal plants have several potential antimicrobial activities either as antifungal or antibacterial to fight against the disease and pathogen that attack the plants. The extractions of the Aloe vera leaf, Citrus hystrix leaf, Zingiber officinale rhizome and Sabah snake grass were selected in this study to fight against Bacillus subtilis. B. subtilis is a Gram-positive bacterium, rodshaped and catalase-positive that lives on decayed organic material. It is known as Gram-positive bacteria because of its thick peptidoglycan and would appear purple when subjected to Gram test. This species is commonly found in the upper layers of the soil, in meat or vegetables, in pastry, cooked meat, in bread or poultry products. The extracts of Sabah Snake Grass found to be most effective than A.vera leaf, Z. officinale, and C. hystrix against the B. subtilis

Preliminary Studies on Antimicrobial Activity of Extracts from Aloe Vera Leaf, Citrus Hystrix Leaf, Zingiber Officinale and Sabah Snake Grass Against Bacillus Subtilis

Herbal plants have several potential antimicrobial activities either as antifungal or antibacterial to fight against the disease and pathogen that attack the plants. The extractions of the Aloe vera leaf, Citrus hystrix leaf, Zingiber officinale rhizome and Sabah snake grass were selected in this study to fight against Bacillus subtilis. B. subtilis is a Gram-positive bacterium, rodshaped and catalase-positive that lives on decayed organic material. It is known as Gram-positive bacteria because of its thick peptidoglycan and would appear purple when subjected to Gram test. This species is commonly found in the upper layers of the soil, in meat or vegetables, in pastry, cooked meat, in bread or poultry products. The extracts of Sabah Snake Grass found to be most effective than A.vera leaf, Z. officinale, and C. hystrix against the B. subtilis