Valence band spectroscopy in V-grooved quantum wires

We present a combined theoretical and experimental study of the anisotropy in the optical absorption of V-shaped quantum wires. By means of realistic band structure calculations for these structures, we show that detailed information on the heavy- and light-hole states can be singled out from the anisotropy spectra {\em independently of the electron confinement}, thus allowing accurate valence band spectroscopy.Comment: To be published in Appl. Phys. Lett. (8 pages in REVTeX, two postscipt figures

Self-T-Dual Brane Cosmology and the Cosmological Constant Problem

We consider a codimension-one brane embedded in a gravity-dilaton bulk action, whose symmetries are compatible with T-duality along the space-like directions parallel to the brane, and the bulk time-like direction. The equations of motions in the string frame allow for a smooth background obtained by the union of two symmetric patches of AdS space. The Poincar\'{e} invariance of the solution appears to hold independently of the value of the brane vacuum energy, through a self-tuning property of the dilaton ground state. Moreover, the effective cosmology displays a bounce, at which the scale factor does not shrink to zero. Finally, by exploiting the T-duality symmetry, we show how to construct an ever-expanding Universe, along the lines of the Pre-Big Bang scenario.Comment: Minor corrections, comments & references added. Accepted for publicatio

The milk collection problem with time constraint: An optimization study integrating simulation

Transport management and vehicle routing problems play a strong role on a company's efficiency and competitiveness. In the food sector, the complexity of the problem grows because of strict constraints. This paper addresses the dairy transportation problem and in particular tries to optimize the milk collection process of a real company. A two-step approach has been proposed to test the current system and solve the routing problem. First, starting from the “As is” collection tours, a travel salesman problem has been modelled. Later, the Nearest Neighbor algorithm has been implemented in order to find a global optimal solution. Finally, a stochastic simulation model integrates the solutions of the previous step in order to test the feasibility of the outcomes, primarily in terms of their capability to meet the time constraints of the tours. Results show that the greedy approach allows less vehicles to be involved, with a good potential on annual cost saving. On the other hand, the simulation outcomes highlight a borderline case, which is not always in line with the time constraints of the problem

Exploiting exciton-exciton interactions in semiconductor quantum dots for quantum-information processing

We propose an all-optical implementation of quantum-information processing in semiconductor quantum dots, where electron-hole excitations (excitons) serve as the computational degrees of freedom (qubits). We show that the strong dot confinement leads to an overall enhancement of Coulomb correlations and to a strong renormalization of the excitonic states, which can be exploited for performing conditional and unconditional qubit operations.Comment: 5 pages revtex, 2 encapsulated postscript figures. Accepted for publication in Phys. Rev. B (Rapid Communication

Pengaruh Permainan Mencocokan Tulisan dengan Gambar Beserta Video terhadap Peningkatan Pengetahuan, Sikap dan Perilaku Mengenai Penyakit Skabies pada Siswa Kelas VII dan VIII Pondok Pesantren Darul Mukhlisin Kota Kendari Tahun 2015

Skabies adalah penyakit kulit yang disebabkan oleh Sercoptes scabiei Var hominis. Prevalensi Skabiessangat tinggi pada lingkungan dengan tingkat kepadatan penghuni yang tinggi dan kebersihan yang kurangmemadai. Menurut World Health Organization (WHO) angka kejadian Skabies pada tahun 2014 sebanyak 130juta orang didunia. Menurut Internasional Alliance for the Control Of Scabies (IACS) kejadian Skabies bervariasimulai dari 0,3% menjadi 46%. penelitian ini dilakukan untuk menurunkan prevalensi penyakit Skabies dengancara metode pembelajaran aktif yang dilakukan di intitusi pendidikan. Salah satu intitusi pendidikan yangcukup erat dengan penyakit ini adalah pondok pesantren karena kehidupan para santri cukup salingberdekatan. Aktivitas mereka banyak dilakukan secara bersama-sama. Penelitian ini disusun dengan tujuanmengetahui apakah ada hubungan permainan mencocokan tulisan dengan gambar beserta video terhadappeningkatan pengetahuan, sikap dan perilaku mengenai penyakit Skabies pada Siwa Kelas VII dan VIII PondokPesantren Darul Muhklisin tahun 2015. Metode yang digunakan yaitu metode penelitian Pra-Eksperimendengan menggunakan rancangan one group pre test and post test design. Subjek penelitian sebanyak 21 orang.Sampel ditentukan dengan teknik purposive sampling berdasarkan kriteria inklusi dan eksklusi. Analisis datayang digunakan yaitu uji statistik Mc Nemar. Hasil penelitian tentang permainan edukatif dan video mengenaiSkabies memiliki pengaruh yang bermakna terhadap peningkatan pengetahuan, sikap, dan perilaku padakelompok eksperimen. Hal ini dibuktikan dengan adanya perbedaan pengetahuan, sikap, dan perilakuresponden sebelum dan sesudah diberikan permainan edukatif selama 21 hari

Valence band spectroscopy in V-grooved quantum wires

We present a combined theoretical and experimental study of the anisotropy in the optical absorption of V‐shaped quantum wires. By means of realistic band structure calculations for these structures, we show that detailed information on the heavy‐ and light‐hole states can be singled out from the anisotropy spectra independently of the electron confinement, thus allowing accurate valence band spectroscopy

CFD Model of a Molten Salt Tank with Integrated Steam Generator

Abstract For each solar technology the dispatchable CSP plant scheme that maximizes the solar to electrical energy conversion and minimizes the costs associated to such transformation is searched. In recent years double tank TES systems are evolving towards more simple configurations of a single tank [1] , [2] , [3] , also known as thermocline tank TES systems and, even going beyond, there are already thermocline tanks in process of development where the steam generator (SG) is integrated into the storage tank (European project OPTS). A prototype with integrated SG has been erected for testing purpose in the Casaccia Research Centre of ENEA (Italy) [4] . The model presented in this paper reproduces the experimental data of such prototype using the CFD commercial code STAR-CCM + [5] . Unlike very few published until now [6] . The simulated system account for molten salts behavior, not only for the bulk molten salts, but also for the circulation of the molten salts inside the SG (with three steam coils). The molten salts move by induced natural convection and the steam temperatures and pressures are up to ∼500° C/40 bar. Temperature gauges situated in the bulk and the molten salts mass flow inside the SG are the main variables considered for validating the model. From the numerical point of view is a transient simulation and the model is 2D-axisymmetric. The required features of the system mesh and the physical models used are presented in this work

Intrinsic exciton-exciton coupling in GaN-based quantum dots: Application to solid-state quantum computing

In this Rapid Communication we propose to use GaN-based quantum dots as building blocks for solid-state quantum-computing devices. The existence of a strong built-in electric field induced by the spontaneous polarization and by the piezoelectricity is exploited to generate entangled few-exciton states in coupled quantum dots without resorting to external fields. More specifically, we shall show how the built-in field induces intrinsic exciton-exciton coupling, which can be used to realize basic quantum information processing on a sub-picosecond time scale

Kajian Karakteristik Profil Pantai dengan Menggunakan Metode Equilibrium Beach Profile di Kecamatan Sinaboi Kabupaten Rokan Hilir

Coastal area is a very vulnerable to changes, because dynamic movement which are cause by the wave. A wave move bring a very easy basic particle coast and make errotion andaccresion in some area of coast. But, a coast will be return into a basic form if they had a balance character. Equilibrium Beach Profile (EBP) method is empirical correlation a scale parameter and the sediment size or fall velocity allow computation z = Ax2/3. Thismethod first time applicated by Robert G Dean in the beach California, United States. A purpose of research is want to know a balance of the coast in Sinaboi, Rokan Hilir with Equilibrium Beach Profile method. From analysis cross section data in some area, a slope formed by Equilibrium Beach Profile method almost approaching existing slope. A some cross section data which has a difference with existing slope and then justified a parameter