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: Regresi Terboboti Geografis dengan Fungsi Pembobot Kernel Gaussian pada Kekuatan Sinyal Seluler
Abstrak: Kekuatan sinyal jaringan seluler dapat dipengaruhi oleh lokasi sehingga penelitian yang berkaitan dengan kekuatan sinyal membutuhkan informasi berupa lokasi pengamatan dan teknik analisis yang memperhatikan aspek spasial. Analisis regresi spasial memperhitungkan faktor lokasi dalam memodelkan hubungan antara peubah penjelas dengan peubah respon. Salah satu metode analisis regresi spasial adalah Regresi Terboboti Geografis (RTG). Metode ini memanfaatkan faktor lokasi sebagai matriks pembobot yang dibentuk menggunakan fungsi pembobot. Analisis RTG dengan fungsi pembobot kernel Gaussian menghasilkan model yang lebih baik dari model regresi Metode Kuadrat Terkecil. Model yang dihasilkan RTG berupa model lokal dengan penduga parameter yang berbeda-beda pada setiap titik amatan. Penggerombolan titik amatan dilakukan untuk meringkas hasil RTG. Jumlah gerombol optimal pada penggerombolan berdasarkan koefisien penduga parameter adalah lima gerombol sedangkan pada penggerombolan berdasarkan nilai-p hasil uji-t sebanyak empat gerombol.
Keyword: analisis gerombol, kernel gaussian, regresi terboboti geografis

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