Judul: Study of simplicial complex and kth Betti number on coverage of indoor GSM signal booster network.
Abstrak: Sinyal perangkat mobile sering kali menghilang saat memasuki gedung beratap. Masalah tersebut dapat diatasi dengan menambahkan penguat sinyal di dalam gedung beratap. Tujuan penelitian ini ialah mengonstruksi cakupan jaringan penguat sinyal dalam suatu ruangan dengan konsep simplicial complex dan kth Betti number. Simplicial complex adalah objek amatan yang berada pada ruang topologi dan kth Betti number merupakan ciri atau karakteristik dari objek amatan yang berada pada ruang topologi. Dengan software Matlab R2008b yang terintegrasi JPlex dan Wolfram Mathematica7, cakupan jaringan penguat sinyal dalam suatu ruangan dapat dikonstruksi. Langkah-langkah yang dilakukan ialah: memasukkan koordinat titik, memberikan diameter cakupan jaringan penguat sinyal, dan menganalis koordinat titik dengan konsep simplicial complex dan kth Betti number. kth Betti number dari suatu simplicial complex dilambangkan dengan βk . Nilai β0 adalah jumlah unit yang terhubung dari suatu simplicial complex dan nilai β1 adalah jumlah lingkaran lubang dari suatu simplicial complex., The mobile devices signal often disappear when entering the building. The problem could be solved by equipping the building with a signal amplifier. The purpose of this study is to construct a network coverage signal booster in a room with the concept of simplicial complex and kth Betti number. Simplicial complex is observed objects in the topological space and the kth Betti number is a trait or characteristic of the observed objects in the topological space. Using integrated Matlab R2008 with JPlex and Wolfram Mathematica7, the network coverage in an indoor signal booster can be constructed. The performed steps are: enter the coordinates of points, give the diameter of network coverage signal amplifier, and analyze coordinates of points the concept of simplicial complex and kth Betti number. kth Betti number of a simplicial complex is denoted by βk. β0 denotes the number of connected units of a simplicial complex and β1 denotes the number of circular holes of a simplicial complex. Keywords: kth Betti number, simplicial complex, topology
Keyword: kth Betti number, simplicial complex, topologi

Judul: Analisis dan Evaluasi Infrastruktur Jaringan Nirkabel Berbasiskan Standar IEEE 802.11 (Studi Kasus di Institut Pertanian Bogor)
Abstrak: Infrastruktur jaringan wireless fidelity (WiFi) milik IPB belum dikelola secara optimal saat ini. Hal ini menyebabkan banyaknya interferensi antar perangkat WiFi sehingga area jangkauannya menjadi tidak optimal. Oleh karena itu, diperlukan sebuah rekomendasi rancangan infrastuktur WiFi yang dapat mengoptimalkan kinerja jaringan. Penelitian ini menggunakan dua model desain infrastruktur jaringan WiFi, yaitu model koneksi langsung dan model koneksi bridging/relaying. Pengujian dilakukan dengan menggunakan dua skenario aktivitas pengguna, yaitu diam dan bergerak untuk mengukur tiga variabel kinerja jaringan, yaitu latency, throughput, dan signal-to-noise ratio (SNR). Pada model koneksi langsung dengan skenario kondisi pengguna diam menghasilkan nilai kinerja latency rata-rata 2.5 ms dan model koneksi bridging/relay 165.4 ms. Untuk skenario kondisi pengguna bergerak pada koneksi langsung waktu perpindahan AP rata-rata 2.9 detik dan koneksi bridging/relay 6.2 detik. Sementara itu, untuk hasil pengujian throughput pada koneksi langsung memiliki nilai rata-rata 7.185 Mbps dan koneksi bridging/relay 1.364 Mbps. Dengan hasil yang didapatkan, maka kinerja yang terbaik adalah model koneksi langsung.
Keyword: bridging/relay, interferensi, nirkabel, roaming, WiFi

Judul: Mercury Toxicity and It’s Effect on Histopathology Change of Nile Tilapia (Oreochromis niloticus).
Abstrak: Nile tilapia (Oreochromis niloticus) is one of fish species that oportunity to contaminated with mercury. The effects of pollutants can damage living organisms organs and can cause death. The effects caused mercury had acute or chronic character. The aims of this study are to determine threshold and acute toxicity of mercury chloride (HgCl2) of Nile tilapia (Oreochromis niloticus), to assess the effect of mercury chloride (HgCl2) on several biometric parameters (survival, growth rate of average daily weighted, liver condition, bile and reproductive variability of Nile tilapia (Oreochromis niloticus), assess the level of damage to the histological structure of the gills, liver and kidney of Nile tilapia (Oreochromis niloticus) caused mercury chloride (HgCl2) exposure. This study was conducted from February to June 2013. Nile Tilapia (Oreochromis niloticus) were used in this study were female with average weight 20 grams or 11-13 cm length range. Toxicant materials used in this study was mercury chloride (HgCl2). Fish were reared in each aquarium 60x40x30 containing 48 liters of water. This study consists of three stages: a preliminary test, acute test, and sub-chronic test. To determine the changes in biometric condition of tilapia approximated by measuring the survival rate (SR), the growth rate of average daily weight , the content of mercury in the fish organs, hepatosomatic index (HSI), the relative bile volume (VER), gonadal soamtic index (IKG), fecundity and oocit diameter, tissue damage caused by mercury in fish organs by making histological preparations stained with hematoxylin and eosin. The median lethal concentration (96 hr, LC50) of Mercury Chloride was calculated as 1,64 mgL--1.The survival rate was highest in the control treatment (46,67 %) . Mercury chloride with concentration 0.196 mgL--1 show significant effect to changes HSI and relative bile volume, and oocyte diameter of Nile tilapia (p < 0,05). Mercury chloride with a concentration of 0,164 mgL-1 and 0,196 mgL-1 have not a significant effect on the growth rate of weight, gonadal somatic index and fecundity of Nile tilapia (p > 0,05). Mercury chloride cause damage to gills (hyperplasia, hypertrophy, proliferation and neukrosis), liver (hyperplasia, hemorhage, shrinkage of hepatocytes, proliferation and neukrosis) and kidney (hyperplasia, hemorrhage, shrinkage of the glomerulus, proliferation and neukrosis).
Keyword: Nile tilapia, Hepatosomatic indexs (HSI), histopathology