A fractal LTB model cannot explain Dark Energy

We revisited the problem of describing, on average, a fractal distribution of matter using a Lemaitre-Tolman-Bondi (LTB) solution. Here we study the fractal structure of our local universe having a fractal dimension and a scale transition. We test our model with the latest type Ia supernova data, the Pantheon compilation, and discuss problems and possible improvements for it, concluding that a fractal transition in LTB cosmology cannot be used to explain the effects of dark energy but it can be useful to study structures at low scales

Aplikasi Mobile Sql Untuk Administrasi Basisdata Postgresql Memanfaatkan Java Servlet

Since a database administrator is not always be in a fix place, we need something that make it possible for the administrator to manage the database anywhere. A Mobile SQL technology is flexible enough for an administrator to do this maintenance job immediately, such as for query operation, and database recovery. Our goal is to develop such application using Java ME and Servlet technology, thus making it runs on every mobile device that has MIDP 2.0, CLDC 1.1, and GPRS enabled device. While on a server computer, it needs web server and a DBMS. For this purpose, an object-oriented DBMS Postgre has been choosen. The main features of this application are: executing SQL queries; creating tables and users; making database backup and recovery; creating and executing SQL procedural language – PL/pgSQL; and sending a log through email. This application will also notify another adminstrator through email for any changes that has been made in the databas

The potential for high performance HgCdTe arrays at 4 microns

The potential of existing technology at Rockwell International in terms of the goals for astronomical detector arrays in the 3 to 5 micron interval is evaluated. Measurements have been obtained for a number of samples of HgCdTe diodes manufactured by Rockwell International. All the diodes reported on here had cutoff wavelengths at high temperatures of 4.6 to 4.7 microns. Although no confirming measurements were made, the cutoff wavelength is expected to move to 5 microns or beyond at the low temperatures of our tests. Diode sizes ranged from 20 to 150 microns. The test program yielded full diode curves and relative response at 3.4 microns for the sample diodes as a function of temperature. Dark currents are quoted below as the current passing through the diode with a back bias of 50 mV. The various diode types showed a wide range of behavior, both with regard to dark current and responsibility. The test results for one of the best diode types are illustrated. This detector has a size of 148 microns and a cutoff wavelength of 4.61 microns

Kegunaan Panel Sentuh Aplikasi Ponsel Cerdas Untuk Pengguna Lanjut Usia

Peningkatan populasi orang lanjut usia di dunia telah disadari oleh beberapa pihak, khususnya pemerintah negara maju sperti Amerika Serikat, Inggris, dan negara Eropa. Dengan banyaknya keterbatasan yang dimiliki oleh orang lanjut usia, maka teknologi informasi mempunyai peran krusial untuk membantu agar mereka dapat hidup lebih mandiri. Beberapa pengembang aplikasi ponsel cerdas sudah membuat aplikasi dengan tema kesehatan, keamanan, komunikasi, dan hiburan yang salh satu target penggunanya adalah orang lanjut usia. Masalah yang muncul adalah banyak aplikasi yang dibuat tidak cocok untuk pengguna lanjut usia karena keterbatasan fisik yang ada. Uji coba dilakukan terhadap pengguna ponsel cerdas untuk kategori usia lanjut usia (berumur 65 tahun keatas) dan pengguna usia muda. Peneliti membandingkan tingkat akurasi pengguna usia lanjut dan usia muda dalam menggunakan aplikasi ponsel cerdas yang memiliki layar sentuh. Dari hasil penelitian ini ditemukan beberapa faktor yang mempengaruhi tingkat akurasi penggunaan layar sentuh pada pengguna usia lanjut yaitu posisi target, ukuran target, dan besar layar ponsel

Monopole Vector Spherical Harmonics

Eigenfunctions of total angular momentum for a charged vector field interacting with a magnetic monopole are constructed and their properties studied. In general, these eigenfunctions can be obtained by applying vector operators to the monopole spherical harmonics in a manner similar to that often used for the construction of the ordinary vector spherical harmonics. This construction fails for the harmonics with the minimum allowed angular momentum. These latter form a set of vector fields with vanishing covariant curl and covariant divergence, whose number can be determined by an index theorem.Comment: 21 pages, CU-TP-60

Linear stability of coherent systems and applications to Butler's conjecture

The notion of linear stability of a variety in projective space was introduced by Mumford in the context of GIT. It has subsequently been applied by Mistretta and others to Butler's conjecture on stability of the dual span bundle (DSB) $M_{V, E}$ of a general generated coherent system $( E, V )$. We survey recent progress in this direction on rank one coherent systems, prove a new result for hyperelliptic curves, and state some open questions. We then extend the definition of linear stability to generated coherent systems of higher rank. We show that various coherent systems with unstable DSB studied by Brambila-Paz, Mata-Gutierrez, Newstead and Ortega are also linearly unstable. We show that linearly stable coherent systems of type $(2, d, 4)$ for low enough $d$ have stable DSB, and use this to prove a particular case of a generalized Butler conjecture. We then exhibit a linearly stable generated coherent system with unstable DSB, confirming that linear stability of $( E, V )$ in general remains weaker than semistability of $M_{V, E}$ in higher rank. We end with a list of open questions on the higher rank case.Comment: 21 page

Grup Google Hangouts Rinfo sebagai Media Diskusi Kelas pada Perguruan Tinggi Raharja

Teknologi informasi yang berkembang pesat terus melahirkan inovasi yang mempermudah manusia dalam melakukan komunikasi dan mendapatkan informasi. Dengan berkembangnya suatu teknologi kita dapat berinteraksi dengan satu sama lain tanpa ada batasan tempat dan waktu. Hal ini dapat terjadi karena adanya suatu wadah (forum) komunitas yang bisa dijadikan media untuk berdiskusi secara online. Pada Perguruan Tinggi Raharja, setiap mahasiswa diberikan fasilitas berupa email resmi yaitu Rinfo yang digunakan sebagai media  komunikasi. Namun saat ini belum tersedia wadah untuk berdiskusi antara mahasiswa dan dosen, sehingga proses diskusi pembelajaran belum efektif dan efisien karena masih dilakukan secara tatap muka. Oleh karena itu, diperlukannya pemanfaatan RinfoApps yang dapat digunakan sebagai wadah diskusi pembelajaran online. Hangouts merupakan salah satu GoogleApps yang dapat dimanfaatkan sebagai wadah formal untuk proses diskusi pembelajaran online. Dengan membuat Grup Google Hangouts di setiap kelas, mahasiswa dan dosen dapat berdiskusi di luar jam perkuliahan, dosen dapat sharing mengenai bahan materi pembelajaran. Dalam penelitian ini, ditemukan 3 (tiga) permasalahan pada keadaan saat ini. Lalu dengan didukung 2 (dua) metode penelitian yaitu metode observasi dan studi pustaka. Hasil akhir yang dicapai dari penelitian ini yaitu terbentuknya media diskusi yang dapat di akses dimana dan kapan saja sehingga proses diskusi antara mahasiswa dan dosen menjadi lebih efektif dan efisien. &nbsp

Cyclic catalytic upgrading of chemical species using metal oxide materials

Processes are disclosure which comprise alternately contacting an oxygen-carrying catalyst with a reducing substance, or a lower partial pressure of an oxidizing gas, and then with the oxidizing gas or a higher partial pressure of the oxidizing gas, whereby the catalyst is alternately reduced and then regenerated to an oxygenated state. In certain embodiments, the oxygen-carrying catalyst comprises at least one metal oxide-containing material containing a composition having one of the following formulas: (a) Ce.sub.xB.sub.yB'.sub.zB''O.sub..delta., wherein B=Ba, Sr, Ca, or Zr; B'=Mn, Co, or Fe; B''=Cu; 0.01<x<0.99; 0<y<0.6; 0<z<0.5; and 1<.delta.<2.2; (b) Sr.sub.vLa.sub.wB.sub.xB'.sub.yB''.sub.zO.sub..delta., wherein B=Co or Fe; B'=Al or Ga; B''=Cu; 0.01<v<1.4; 0.1<w<1.6; 0.1<x<1.9; 0.1<y<0.9; 0<z<2.2; and 3<.delta.<5.5)