Quantum mechanical scattering investigation of the thermionic and field induced emission components of the dark current in quantum well infrared photodetectors

The thermionic emission and field induced emission components of the dark current in quantum well infrared photodetectors are investigated using a quantum mechanical scattering theory approach. Calculations are performed for an experimentally reported device. Using this as a standard, the device dimensions were altered in order to increase its detection wavelength to cover the mid- (MIR) and far-infrared (FIR) regions of the spectrum. The behavior of the scattering mechanisms that contribute to the thermionic emission and field induced emission components were studied. The results highlight the change in the dominating scattering mediator across the MIR and FIR bands. © 2002 American Institute of Physics

Computer Assembly of Cluster-Forming Amphiphilic Dendrimers

Recent theoretical studies have predicted a new clustering mechanism for soft matter particles that interact via a certain kind of purely repulsive, bounded potentials. At sufficiently high densities, clusters of overlapping particles are formed in the fluid, which upon further compression crystallize into cubic lattices with density-independent lattice constants. In this work we show that amphiphilic dendrimers are suitable colloids for the experimental realization of this phenomenon. Thereby, we pave the way for the synthesis of such macromolecules, which form the basis for a novel class of materials with unusual properties.Comment: 4 pages, 4 figures, 1 tabl

Statistical model for intermittent plasma edge turbulence

The Probability Distribution Function of plasma density fluctuations at the edge of fusion devices is known to be skewed and strongly non-Gaussian. The causes of this peculiar behaviour are, up to now, largely unexplored. On the other hand, understanding the origin and the properties of edge turbulence is a key issue in magnetic fusion research. In this work we show that a stochastic fragmentation model, already successfully applied to fluid turbulence, is able to predict an asymmetric distribution that closely matches experimental data. The asymmetry is found to be a direct consequence of intermittency. A discussion of our results in terms of recently suggested BHP universal curve [S.T. Bramwell, P.C.W. Holdsworth, J.-F. Pinton, Nature (London) 396, 552 (1998)], that should hold for strongly correlated and critical systems, is also proposedComment: 13 pages. Physica Review E, accepte

Respon Pertumbuhan Tanaman Kangkung Darat(ipomoea Reptans Poir) Terhadap Pupuk Bioboost Dan Pupuk Za

Tujuan dari penelitian ini untuk menentukan upaya untuk meningkatkan produksi kangkung darat (Ipomoea reptans Poir). Tumbuh tanaman dan produksi yang tinggi dapat dicapai dengan mengamati kebutuhan dan perawatan intensif berkembang. Salah satu cara penting bahwa fertilisasi pemeliharaan. Tujuan dari belajar untuk mengetahui pengaruh pupuk dan pupuk kandang Bioboost ZA terhadap pertumbuhan dan produksi selada darat. Penelitian dilakukan di Desa Lempeni, Kecamatan Tempeh, Lumajang pada 8 Juli 2015 sampai dengan 19 Agustus 2015. Metode penelitian dilaksanakan menggunakan rancangan acak kelompok (RAK) faktorial dengan dua faktor. Faktor pertama adalah konsentrasi Bioboost pupuk terdiri dari: tanpa pupuk Bioboost 0 ml / l air, konsentrasi pupuk Bioboost dari 2 ml / l air, konsentrasi pupuk Bioboost dari 4 ml / l air dan Bioboost pupuk konsentrasi 6 ml / l air. Faktor kedua terdiri dari: tanpa ZA 0 g, 7,5 g dosis ZA, ZA dosis 15 g dan 22,5 dosis g ZA. Setiap kombinasi perlakuan diulang tiga kali. Hasil penelitian menunjukkan bahwa penggunaan pupuk Bioboost menunjukkan secara signifikan berbeda tanggapan dan sangat signifikan untuk tinggi tanaman, jumlah daun, panjang daun, diameter dan volume akar batang. Untuk ZA menunjukkan respon yang sama. Namun, interaksi pupuk ZA Bioboost tidak menunjukkan respon terhadap kangkung darat (Ipomoea reptans Poir)

Implementasi Balanced Scorecard sebagai Alat Pengukur Kinerja pada Rumah Sakit Bhayangkara Polda Bengkulu

Antoni Sibarani, Nani Halima Zahara; The Implemetation of Balanced Scorecard as a tool of measuring performance in Bayangkara Polda Hospital of Bengkulu. This research aims to determine how the performance of Hospital by using the “Balanced Scorecard”. The use of “Balanced Scorecard” is expected that hospital can improve/develop the financial and non-financial performances for measuring the evaluation activity, so it will provide the satisfication to the customers, employers, and also sufficient surplus. This study took the data within the lastest two years (2011 to 2012) by using a comparative analysis, the researcher evaluated the performances of hospital between several periods and then compare with the pervious targets which have been set and scored according to the criteria. The data obstained from some sources; the evaluations of Hospital Bhayangkara within four perspectives; financial, customers, internal bussiness processes, and learning and growth . From the results of the study the concept of the Balanced Scorecard measurement can be deduced from the overall performance of Bhayangkara Hospital Bengkulu is 0.57. This study showed that Hospital Bhayangkara getting better if it is measured with the Balanced Scorecard approach

Radio pulses from cosmic ray air showers - Boosted Coulomb and Cherenkov fields

High-energy cosmic rays passing through the Earth's atmosphere produce extensive showers whose charges emit radio frequency pulses. Despite the low density of the Earth's atmosphere, this emission should be affected by the air refractive index because the bulk of the shower particles move roughly at the speed of radio waves, so that the retarded altitude of emission, the relativistic boost and the emission pattern are modified. We consider in this paper the contribution of the boosted Coulomb and the Cherenkov fields and calculate analytically the spectrum using a very simplified model in order to highlight the main properties. We find that typically the lower half of the shower charge energy distribution produces a boosted Coulomb field, of amplitude comparable to the levels measured and to those calculated previously for synchrotron emission. Higher energy particles produce instead a Cherenkov-like field, whose amplitude may be smaller because both the negative charge excess and the separation between charges of opposite signs are small at these energies.Comment: 10 figures - Accepted by Astronomy & Astrophysic

Sensory Evaluation and Chemical Characteristic of Catfish (Pangasius Hypophthalmus) Meatball Made of Different Handled Raw Material

This research was purposed to evaluate the sensory and chemical characteristic of catfish (Pangasius hypophthalmus) meatball made of different handled raw material, namely: fresh fish meat, refrigerated fish meat and frozen fish meat. The research methodology used was experimental and composed as non factorial completely randomized design (CRD). The parameters used were sensory value (appearance, odor, taste and texture), proximate chemical composition (moisture, protein and fat), and the value folding test. The result showed that the different raw material handling was significantly affected to all parameters. The best treatment was the using of fresh fish meat as the raw material of catfish (Pangasius hypophthalmus) meatball. It was characteristically appeared circle uniform, without hollow space, and cream white color (7,68), disputrid, characteristically specific fish meatball odor (7,76), characteristically, fish tasted (7,88), solid, compact and elastic texture, (8,12), and folding test criteria was not broken when folded at half and quarter circle (4,73). The fish meatball contained moisture 32, 85%, protein 28,17%, fat 7,96% and ash 8,03 %

ANALISIS KINERJA PANEL SURYAAKIBAT PENDINGINAN AKTIF

Energi surya dapat menghasilkan dua jenis energi yaitu energi cahaya dan energi panas. Kedua energi tersebut dapat dimanfaatkan dalam berbagai aktivitas manusia, salah satunya untuk menghasilkan energi listrik. Kajian awal menyimpulkan bahwa kenaikan temperatur permukaan sebesar 1oC akan menurunkan daya keluaran dan efisiensi panel surya sebesar 0,5%. Peningkatan efisiensi panel surya dapat dilakukan dengan menurunkan atau mempertahankan temperatur panel surya pada kondisi mendekati 25oC dengan sistem pendinginan aktif maupun pasif. Maka itu pada penelitian ini akan melihat kinerja panel surya akibat adanya pendinginan aktif dengan tujuan untuk menganalisis pengaruh perbandingan watercoolant dan air murni sebagai pendingin aktif pada panel surya 130 Wp untuk memperoleh nilai efisiensi panel surya yang optimum. Sudut kemiringan panel surya adalah 10o serta Kecepatan aliran fluida konstan 100 L/Jam. Perbandingan campuran antara watercoolant dan air murni adalah sebagai berikut; 0:1 (air murni saja), 1:20, 1:40, 1:60, 1:80, 1:100. Pada perbandingan air murni, efisiensi meningkat sebesar 16,27%. Perbandingan 1:20, efisiensi meningkat sebesar 16,96%. Perbandingan 1:40, efisiensi meningkat sebesar 17,69%. Perbandingan 1:60, efisiensi meningkat sebesar 17,93%. Perbandingan 1:80, efisiensi meningkat sebesar 22,99%. Perbandingan 1:100, efisiensi meningkat sebesar 16,14%. Dari hasil pengolahan data dan pembahasan, dapat diperoleh bahwa peningkatan efisiensi yang optimal terdapat pada perbandingan 1:80

On the angular distribution of extensive air showers

Angular distributions of extensive air showers with different number of charged particles in the range 2.5x10^5--4x10^7 are derived using the experimental data obtained with the EAS MSU array. Possible approximations of the obtained distributions with different empiric functions available in literature, are analysed. It is shown that the exponential function provides the best approximation of the angular distributions in the sense of the chi-squared criterion.Comment: 5 pages including 1 figur