Scattering of Dirac electrons by circular mass barriers: valley filter and resonant scattering

The scattering of two-dimensional (2D) massless Dirac electrons is investigated in the presence of a random array of circular mass barriers. The inverse momentum relaxation time and the Hall factor are calculated and used to obtain parallel and perpendicular resistivity components within linear transport theory. We found a non zero perpendicular resistivity component which has opposite sign for electrons in the different K and K' valleys. This property can be used for valley filter purposes. The total cross-section for scattering on penetrable barriers exhibit resonances due to the presence of quasi-bound states in the barriers that show up as sharp gaps in the cross-section while for Schr\"{o}dinger electrons they appear as peaks.Comment: 10 pages, 11 figure

Supply Chains Analysis of Choosing Supplier in Restaurant (Case Study : New Hongkong Restaurant)

A good quality of product does come from a good supplier. That what makes Supplier's quality is paramount for every company. This research is conducted to find the best way for choosing supplier for our company. We believe our research can be successfull due to the fact that there is only few of research here in Indonesia that concern about the importance of choosing the right supplier for the enterprise. We use New hongkong Restaurant as our case study with interview method as our way to collect the data as well as secondary data which will be collected from supplier and company that we choose. The data itself will be analyzed qualitatively in order to determind the right supplier for the enterprise. Keywords: Supplier, Retail Management, New Hongkong Restaurant, descriptive qualitativ

Comparison of in situ aerosol measurements with SAGE 2 and SAM 2 aerosol measurements during the airborne Antarctic ozone experiment

Models indicate that stratospheric aerosols play a major role in the destruction of ozone during the Austral winter. Although many in situ measurements of stratospheric aerosols were made during the Airborne Antarctic Ozone Experiment, changes of aerosol concentration and size distributions across the polar vortex are important to understanding changes of chemical species taking place during this time. Therefore comparing the in situ measurements with measurements made by satellites scanning wider areas will give a clearer picture of the possible role played by aerosols during this period. The wire impactor size distributions are compared to those from the aerosol spectrometers and a best fit size distribution determined. Aerosol extinctions are calculated from the in situ measurements and compared to the extinctions measured by the satellites. Five comparisons are made with SAGE 2 and four with SAM 2. Extinctions agree as close as a factor of two

Coherent transport through graphene nanoribbons in the presence of edge disorder

We simulate electron transport through graphene nanoribbons of experimentally realizable size (length L up to 2 micrometer, width W approximately 40 nm) in the presence of scattering at rough edges. Our numerical approach is based on a modular recursive Green's function technique that features sub-linear scaling with L of the computational effort. We identify the influence of the broken A-B sublattice (or chiral) symmetry and of K-K' scattering by Fourier spectroscopy of individual scattering states. For long ribbons we find Anderson-localized scattering states with a well-defined exponential decay over 10 orders of magnitude in amplitude.Comment: 8 pages, 6 Figure

Fenomena Kemiskinan Nelayan: Perspektif Teori Strukturasi

Tulisan ini merupakan hasil studi lapangan yang menggambarkan realitas kemiskinan nelayan di Desa Teluk, Kecamatan Labuan, Kabupaten Pandeglang-Banten. Dengan menggunakan teori Strukturasi Giddens, kemiskinan nelayan dijelaskan sebagai produk dari dinamika relasi agen dan struktur yang melembagakan praktik sosial dalam kehidupan masyarakat nelayan. Lewat metode studi kasus, maka, tampak dengan jelas betapa proses strukturasi yang berlangsung bukannya membebaskan kaum nelayan dari perangkap kemiskinan, sebaliknya justru melanggengkan kemiskinan yang ada. Dengan kata lain, struktur juga bisa bersifat constraint (unenabling), sehingga Perubahan struktural yang terjadi bukan memberdayakan melainkan bersifat mereproduksi dan melanggengkan kemiskinan kaum nelayan. This paper is the result of field studies that illustrate the reality of poverty in the fishing village of Teluk, District of Labuan, Pandeglang, Banten. By using the theory of Structuration Giddens, poverty fisherman explained as a product of the dynamics of relations agents and structures that institutionalize social practices in the life of the fishing community. Through the case study method, then, appears clearly how the structuration process that takes place instead of freeing the fishermen of the poverty trap, instead perpetuate the poverty that exists. In other words, the structure can also be constraints (unenabling), so that the structural changes taking place not empowering but rather reproduce and restless-gengkan poverty of the fishermen

Manajemen Resiko Proyek Pembangunan Saluran Udara Tegangan Tinggi (Sutt) 150 Kv Lopana-teling

Sebagai upaya pemenuhan kebutuhan pasokan listrik di berbagai pusat beban seperti kota, kawasan industri, permukiman dan lainnya, diperlukan sarana yang mampu menyalurkan tenaga listrik. Salah satu bentuk sarana yang digunakan adalah Saluran Udara Tegangan Tinggi. Proyek pembangunan Saluran Udara Tegangan Tinggi (SUTT) 150 kV Lopana – Teling merupakan proyek pembangunan saluran transmisi dengan tegangan 150 kiloVolt yang menghubungkan antara Gardu Induk Tegangan Tinggi Lopana ke Gardu Induk. Penelitian ini akan mengidentifikasi, menganalisis dan menentukan respon resiko yang ditimbulkan akibat adanya proyek pembangunan SUTT 150 kV Lopana–Teling. Analisis kejadian dan konsekuensi dibagi menjadi 7 aspek penting, yaitu aspek teknis pengurusan proyek, aspek kecelakaan kerja tak terduga, aspek lingkungan, aspek penyesuaian dalam proyek, aspek permasalahan tenaga kerja, aspek kecelakaan kerja yang diperkirakan, aspek penggunaan material. Klasifikasi resiko berdasarkan ranking, yaitu : high risk terdiri dari aspek teknis pengurusan proyek; significant risk terdiri atas aspek kecelakaan tak terduga, aspek lingkungan, aspek penyesuaian dalam proyek; dan low risk terdiri dari aspek permasalahan tenaga kerja, aspek kecelakaan kerja yang diperkirakan, aspek penggunaan material. Respon penanganan resiko terhadap 7 aspek yang dominan adalah melakukan koordinasi awal dengan pihak pemerintah setempat dan PT. PLN Persero selaku pemrakarsa proyek, diadakan pendidikan dan pelatihan K3, serta melakukan koordinasi dengan para tenaga ahli dan tenaga terampil, dan diadakan pendidikan dan pelatihan untuk para pekerja dari luar daerah, pekerja penduduk setempat yang dilalui jaringan T/L 150 kV Lopana-Teling, mengikut sertakan para tenaga ahli dan tenaga terampil di dalam lokasi proyek, meningkatkan peralatan dan kelengkapan K3, mengikuti pendidikan dan pelatihan mengenai K3, serta mengikut sertakan warga sekitar proyek dalam proses pembangunan, dan melakukan berbagai pendekatan-pendekatan sosial kepada pemerintah setempat, tokoh masyarakat, tokoh agama yang berada di lingkungan proyek, serta memberikan sosialisasi kepada masyarakat mengenai keamanan SUTT tersebut

Penerapan Konsep Arsitektur Post Modern Pada Pengembangan Bangunan Universitas Dumoga Di Kotamobagu

Perkembangan pembangunan pendidikan di Kota Kotamobagu sangat pesat seiring dengan perkembangan ekonomi. Pengembangan Bangunan Universitas Dumoga Kotamobagu (UDK) menjadi sangat penting bagi penyediaan sarana pendidikan untuk masyarakat Kota Kotamobagu dan sekitarnya. Kondisi bangunan UDK saat ini sangat tidak layak untuk menampung jumlah mahasiswa yang kian tahun bertambah. Lokasi UDK yang berada di pusat kegiatan kota, juga menjadi penting untuk membentuk estetika kawasan pusat kota, sehingga sangat penting juga untuk mengembangkan bentuk bangunan UDK menjadi bentuk bangunan yang memiliki nilai estetika. Arsitektur Post Modern adalah Arsitektur yang berkembang setelah era Arsitektur modern dimana aliran Arsitektur yang baru ini mempunyai tujuan menolak menyempurnakan, dan mengkoreksi terhadap kesalahan yang telah terjadi pada arsitektur modern dimasa yang sebelumnya

Sistem Pakar Diagnosa Penyakit Pada Ayam Dengan Metode Forward Chaining

Is chicken. Chicken had a variety of illnesses. For Some farmers who want to raise chickens especially lay people hit by several problems one of which is a disease. Required to diagnose a disease symptoms appear on the body of the chicken. Necessary seriousness and quick action before it was too late and suffered losses.Therefore, this program is designed to help the farmers in getting some information about chicken diseases. The sooner the disease is known, then the sooner they can prevent it. Identification techniques chosen the chicken disease because the symptoms of common illnesses suffered by chickens are relatively easy to observe and relatievely safe to do by anyone.Applications developed using Visual basic 6.0 and Microsoft Access as the database. Inference method used is a forward chaining, the inference prosess that initiates the search of the premises or in the form of input data lead to the conclusion that the symptoms of the illness conclusions and provide solutions regarding the treatment and prevation advice based on the symptoms observed