Physics

Trion photoluminescence spectra were measured in undoped high-quality GaAs quantum wells. The lineshape is asymmetric with a temperature-dependent tail towards lower photon energies. We have solved numerically the trion Schrodinger equation in the quantum well and found good agreement for both the trion binding energy and the luminescence lineshape at different temperatures. To analyse the relative weight of trion and exciton emission, an equilibrium mass-action law for the respective densities is studied. Using calculated radiative lifetimes, the emission decay after pulsed excitation is found to deviate strongly from a single-exponential shape in case the trions are initially saturated.

We measured the gain dynamics of the ground-state transition at 20 K in an undoped and identically fabricated p-doped InAs/GaAs quantum-dot amplifier. The dynamics in the doped device is dominated by a very short (∼0.1 ps) and a very long (∼300 ps) time constant. These were attributed to hole and electron dynamics, respectively, and quantitatively described by a microstate model. By comparing the dynamics for the same modal gain in the two devices, the gain recovery was initially faster in the p-doped sample, attributed to ultrafast hole-hole scattering, but slower at later times due to the lack of an electron reservoir.

High speed liquid jet forms when a bubble collapses near a solid boundary. The formation of the jet has both advantages and disadvantages as it causes erosion and damage in the nearby turbomachinery and can be beneficially applied in surface cleaning, fluid pumping, etc. In this paper, three-dimensional bubble oscillation between two curved rigid plates is modeled using boundary integral method (BIM). The bubble is incepted at different locations between the plates to investigate the eccentricity effects on the bubble shape, jet formation, etc. The modified Laplacian smoothing technique is implemented on the bubble surface during the jet development to reduce element distortion. The new model is validated with the Rayleigh-Plesset equation as well as with the available experimental data. It was found that the jet velocity increases, and the number of jets is reduced from two to one as the bubble is horizontally shifted away from the centroid. When the bubble is incepted on the horizontal axisymmetric line the jet is horizontal. However, the jet direction changes as the bubble is incepted closer to one of the plates. Finally, the pressure and velocity fields of the fluid surrounding the bubble are provided for better interpretation of the results.

Magnetically frustrated spin systems compose a significant proportion of topological quantum spin liquid candidates. Evidence for spin liquids in these materials comes largely from the detection of fractionalised spin-1/2 quasiparticles, known as spinons. However, the one-dimensional Heisenberg chain, which is topologically trivial, also hosts spinons. Thus, observing spinons does not necessarily signify long-range entanglement. Here, we show that spinons arising from one-dimensional physics leave a clear fingerprint in magnetic Raman scattering. We achieve this by calculating the magnetic Raman intensity of coupled Heisenberg chains. Our findings are in excellent agreement with the magnetic Raman scattering measurements on the anisotropic triangular antiferromagnet Ca3ReO5Cl2.

Introduction: Pesticide poisoning is an important public health problem worldwide. The study aimed to determine the risk of all-cause and cause-specific inpatient mortality and to identify prognostic factors for inpatient mortality associated with unintentional insecticide and herbicide pesticide poisonings. We performed a retrospective cohort study of 3,986 inpatients recruited at hospitalization between 1999 and 2008 in Taiwan. We used the International Classification of Disease, 9th ed., Clinical Modification external causes of injury codes to classify poisoning agents into accidental poisoning by insecticides and herbicides. Comparisons in mortality rates were made between insecticide poisoning patients and herbicide poisoning patients by using the Cox proportional hazards models to estimate multivariable-adjusted hazard ratios (HRs) and their 95% confidence intervals (CIs). Results: There were 168 deaths during 21,583 person-days of follow-up evaluation (7.8 per 1,000 person-days). The major causes of mortality for insecticide poisonings were the toxic effect of organophosphate and coma, and the major causes of mortality for herbicide poisonings were the toxic effect of other pesticides and the toxic effect of organophosphate. The mortality for herbicide exposure was fourfold higher than that for insecticide exposure. The factors associated with inpatient mortality were herbicide poisonings (HR = 4.58, 95% CI 3.29 to 6.37) and receiving mechanical ventilation treatment (HR = 3.85, 95% CI 2.73 to 5.42). We demonstrated that herbicides stand out as the dominant agent for poisoning-related fatalities. The control of and limiting access to herbicide agents and developing appropriate therapeutic regimens, including emergency care, should be priorities.

Background: There is accumulating epidemiologic evidence that exposure to traffic-related air pollutants, including particulate matter (PM) and polyaromatic hydro carbons (PAHs), plays a role in etiology and prognosis of a large scale of illnesses, although the role of specific causal agents and underlying mechanisms for different health outcomes remains unknown. Objective: Our general objective was to assess the relations between personal exposure to traffic exhausts, in particular ambient PM 2.5 and PAHs, and the occurrence of DNA strand breaks by applying personal monitoring of PM and biomarkers of exposure (urinary 1-hydroxypyrene-glucuronide, 1-OHPG) and effect (urinary 8-hydroxydeoxyguanosine, 8-OHdG and DNA strand breaks). We recruited 91 traffic conductors and 53 indoor office workers between May 2009 and June 2011 in Taipei City, Taiwan. We used PM 2.5 personal samplers to collect breathing-zone particulate PAHs samples. Spot urine and blood samples after work shift of 2 consecutive days were analyzed for 1-OHPG, 8-OHdG and DNA strand breaks, respectively. Statistical methods included linear regression and mixed models. Results: Urinary 8-OHdG levels and the occurrence of DNA strand breaks in traffic conductors significantly exceeded those in indoor office workers in mixed models. Particulate PAHs levels showed a positive association with urinary 1-OHPG in the regression model (b = 0.056, p = 0.01). Urinary 1-OHPG levels were significantly associated with urinary 8-OHdG levels in the mixed model (b = 0.101, p = 0.023). Our results provide evidence that exposure to fine particulates causes DNA damage. Further, particulate PAHs could be biologically active constituents of PM 2.5 with reference to the induction of oxidative DNA damages.

Adaptive optics (AO) is a powerful technique to sharpen images that are blurred for example due to atmospheric turbulence or aberrations of the eye. Originally developed for defense applications over a period of 40 years or so, they have found enormous applications in the astronomical and vision research communities. This paper provides an overview of adaptive optics techniques. Using principles of AO, it is possible to develop a laboratory that teaches various optics concepts, including aberration theory, at many levels. In addition, AO can teach students some fundamentals of control theory.

We suggest a near deterministic compact model of a photonic CNOT gate based on a quantum dot trapped in a double sided optical microcavity and a universal cloner. Our design surpasses the cloner optimal limit of 5/6 and we show that it provides fidelity around 91 % in the weak coupling regime.

We apply techniques of optimal control theory namely, the dynamic programming to the problem of light propagation in optical waveguides. The formulation is equivalent to the resolution of an eikonal equation. We illustrate this optimization technique for a gradient profile optical waveguide, i.e., an ideal parabolic refractive index profile distribution. We discuss the possibility of extending this procedure to other type of optical waveguides and optical media and implications in optical design.

We propose a non-deterministic CNOT gate based on a quantum cloner, a quantum switch based on all optical routing of single photon by single photon, a quantum-dot spin in a double-sided optical microcavity with two photonic qubits, delay lines and other linear optical photonic devices. Our CNOT provides a fidelity of 78% with directly useful outputs for a quantum computing circuit and requires no ancillary qubits or electron spin measurements.

Traditional lens design is a numerical and forward process based on ray tracing and aberration theory. This method has limitations because the initial configuration of the lens has to be specified and the aberrations of the lenses have to be considered. This letter is an initial attempt to investigate an analytic and inverse lens design method, called Lagrange, to overcome these barriers. Lagrange method tries to build differential equations in term of the system parameters and the system output and input (object and image). The generalized Snell's law in three-dimensional space and the normal of a surface in fundamental differential geometry are applied. Based on the Lagrange method, equations for a single surface system are derived, which can perfectly image a point object. .

Various ocular diseases and high myopia influence the anatomical reference point Foveal Avascular Zone (FAZ) dimensions. Therefore, it is important to segment and quantify the FAZs dimensions accurately. To the best of our knowledge, there is no automated tool or algorithms available to segment the FAZ's deep retinal layer. The paper describes a new open-access software with a user-friendly Graphical User Interface (GUI) and compares the results with the ground truth (manual segmentation). Ninety-three clinically healthy normal subjects included 30 emmetropia and 63 myopic subjects without any sight-threatening retinal conditions, were included in the study. The 6mm x 6mm using the Angioplex protocol (Cirrus 5000 Carl Zeiss Meditec Inc., Dublin, CA) was used, and all the images were aligned with the centre of the fovea. Each FAZ image corresponding to dimensions 420x420 pixels were used in this study. These FAZ image dimensions for the superficial and deep layers were quantified using the New Automated software Method (NAM). The NAM-based FAZ dimensions were validated with the manually segmented (ground truth) method. The age distribution for all 93 subjects was 28.02 ± 10.79 (range, 10.0 -66.0) years. For normal subjects mean ± SD age distribution was 32.13 ± 16.27 years. Similarly, the myopia age distribution was 26.06 ± 6.06 years. The NAM had an accuracy of 91.40 %. Moreover, the NAM on superficial layer FAZ gave a Dice Similarity Coefficient (DSC) score of 0.94 and Structural Similarity Index Metric (SSIM) of 0.97. On the other hand, the NAM on deep layers FAZ gave a DSE score of 0.96 and SSIM of 0.98. A clinician-friendly GUI software was designed and tested on the FAZ images from deep and superficial layers. The new algorithm outperformed the device's inbuilt algorithm when measuring the superficial layer. This open-source software package is in the public domain and can be downloaded from and can be used to measure the FAZ dimensions in the clinic.

The objective of this research was to study the refining of calophyllum oils and its characterization as a biofuel substitute for diesel fuel. The dosage of phosphoric acid solution of 20% (0.2 -0.3%) and the NaOH concentration (14-18 °Be) were examined to determine the best performance of the refining process and the quality of refined calophyllum oil. The block experimental design and ANOVA (F-test at α = 0.05) were applied to study the effects of dosage of phosphoric acid solution of 20% and NaOH concentration on oil loss and its quality. Generally, the block and the NaOH concentration affected significantly the oil loss and the quality of refined oil. A significant increase of oil loss was observed as increasing of NaOH concentration. The dosage of phosphoric acid solution did not affect the oil loss and the quality of refined oil. However, an increase of the dosage of phosphoric acid solution tended to decrease the ash content and viscosity of refined oil, but did not affect an...

The face gear is used in the spinning machine to lift the spindle mechanism. The face gear are attach with the heart cam for spinning the yarn about spindle. During the working, the tangential force is acting on face gear, which may cause to break the teeth. The tangential load which is acting on the gear is from pinion. The face gear are working similar to the bevel gear and transmitting the power. The intersection axis of both the pinion and gear at right angle to each other. The failure of the gear is due to low strength of the gear material. The beam strength of the face gear is low as compare to the tangential load that why the face gear fail. By changing the material of gear we can prevent the gear from failure. The redesign involve to change the material or to chance the dimension. But in that case, by changing the dimension likes to change the module and thickness which may affect the working of machines. Similarly to change in the setup of machine, in that case it is desira...

Spichiger, nach dem Tode von Prof. Simon fortfahren und abschliessen zu dürfen. Prof. Dr. R. Zenobi danke ich für die Übernahme des Korreferats. Zu Dank verpflichtet bin ich der Optik-Gruppe am Paul-Scherrer-Institut Zürich, besonders Dr. R. Kunz, für die wissenschaftliche Begleitung und Unterstützung bei den Messungen in ihren Labors. Ich stehe in der Schuld meiner Freunde und Kollegen für ihre Hilfe, Unterstützung und viele stimulierende Diskussionen. Der gesamten "Simonia" danke ich für die herzliche Aufnahme und Integration in eine lebhafte und anregende Forschungsgruppe. Besonders danken möchte ich Frau Dr. D. Wegmann für ihre sorgfältige Durchsicht des Manuskripts. und in kurzer Zeit an einer grossen Zahl von Menschen durchführbar sein sollten und eindeutige Ergebnisse liefern.

Cette étude présente une machine frigorifique fonctionnant suivant un cycle à compressionabsorption. Le système proposé utilise le couple ammoniac-eau comme fluide frigorigène et opère à trois niveaux de pression. L'absorbeur fonctionne à une pression intermédiaire Pint, prise entre la pression de l'évaporateur (PEV) et celle du condenseur (PCD). Les principaux éléments du système proposé sont modélisés. Les résultats de la simulation numérique sont comparés à ceux relatifs au système conventionnel. L'étude comparative met en évidence les avantages du système objet de cette étude. Elle prouve le double avantage de la pression intermédiaire non seulement dans l'amélioration des performances de la machine à absorption mais aussi dans la réduction de la température du fonctionnement du générateur. Nous avons montré que pour des températures d'évaporation et de condensation prises respectivement à -10 • C et 40 • C, le cycle frigorifique fonctionne à une température du générateur TGE = 75 • C avec un COP de l'ordre de 0,56. La présente étude révèle que pour les mêmes conditions de fonctionnement, la machine frigorifique simple étage, présente un COP qui ne dépasse pas 0,51 avec une température du générateur de l'ordre de 135 • C. Le système hybride présente ainsi le privilège de fonctionner à basse température et de présenter des performances relativement améliorées.

Tujuan penelitian ini untuk mensimulasikan perhitungan PPN wajib pajak UMKM terhadap kegiatan komersialnya dan membuat aplikasi web penghitungan PPN wajib pajak UMKM. Penelitian ini menggunakan pendekatan studi kasus. Data sekunder yang digunakan berupa data tarif PPN UMKM, tata cara pemotongan PPN UMKM, dan jumlah yang disetorkan atas Pajak Masukan (PM) dan Pajak Keluaran (PK). Teknik analisis data menggunakan metode deskriptif. Tahapan penelitian meliputi pengumpulan data, analisis data, dan pengembangan perangkat lunak. Hasil penelitian berupa aplikasi kalkulator pajak untuk membantu dan memudahkan para UMKM dalam melakukan perhitungan PPN nya.

Pendahuluan: Rhodamin B merupakan suatu pewarna sintetik yang digunakan untuk mewarnai tekstil, sering kali digunakan untuk mewarnai suatu produk makanan, salah satunya adalah Kerupuk. Rhodamin B menyebabkan pembesaran hati dan ginjal. Tujuan:  Untuk mengetahui adanya penggunaan Rhodamin B dalam Kerupuk yang beredar di pasar Kota Medan. Methode: Sampel Kerupuk diambil dari 3 pasar yang ada di Kota Medan yaitu Pasar Helvetia, Pasar Pancing, dan Pasar Sikambing. Sampel di ekstraksi menggunakan metode ekstraksi penyerapan benang wol, dilanjutkan dengan identifikasi menggunakan kromatografi lapis tipis (KLT) kemudian dideteksi dengan lampu UV 254 nm serta  pereaksi Semprot HCl, NaOH 10%, dan NH4OH 12%. Hasil: Data yang diperoleh dianalisis dengan metode deskriptif. Hasil penelitian menunjukkan bahwa sampel yang diperiksa menunjukkan hasil negatif. Kesimpulan: Berdasarkan hasil penelitian ini, beberapa Kerupuk yang beredar di pasar Kota Medan aman untuk dikonsumsi, tetapi harus dilakukan...

Abstrak : Material abu terbang (fly ash) dan abu dasar (bottom ash) yang berasal dari sisa pembakaran batu bara dan rubber sludge dari industri karet merupakan limbah industri. Fly ash mengandung unsur kimia seperti silika, alumina, besi oksida, kalsium oksida, serta unsur logam lainnya yang memiliki sifat sebagai pengikat jika dicampur dengan air. Bottom ash dan rubber sludge juga berfungsi sebagai agregat untuk dapat mengurangi pemakaian pasir. Penambahan abu batubara dan rubber sludge adalah untuk mengetahui pengaruhnya terhadap densitas, dan daya serap batako. Persentase penambahan fly ash adalah 10%, 20%, 30%, 40% dan 50% dari berat awal semen. Persentase penambahan bottom ash dan rubber sludge sebagai agregat adalah 5%, 10%, 15%, 20% dan 25% dari berat awal pasir dengan waktu pengerasan selama 28 hari. Dari hasil pengujian menunjukkan bahwa sampel abu batu bara mengandung logam berat Pb 0,75 ppm; Cr 0,16 ppm; Cu 0,21 ppm; dan sampel rubber sludge mengandung logam Zn sebesar 45...

1. Department of Earth Sciences, Graduate School of Science, Chiba University, 2. Graduate School of Science and Engineering, Chiba University, 3. Southern University of Science and Technology, China, 4. Hokkaido University, 5. Kyoto University, 6. Nagoya Institute of Technology, 7. Aichi Prefectural University, 8. Aichi University, 9. Chubu University, 10. Nihon University, 11. Osaka University, 12. Tokyo Gakugei University, 13. The University of Electro-Communications, 14. National Central University, Taiwan, 15. Chapman University, US, 16. University of Basilicagta, Italy

In order to evaluate the genetic divergence between twelve soybean cultivars, the essays were carried out at Formoso do Araguaia, TO, in the inter-cropping 2007. The soybean cultivars studied were DM Vitória, MG/BR 46 (Conquista), Suprema, BRS Pintado, DM 247, BRS MG 68, BRS MG Liderança, BRS MG Segurança, DM 339, BRS MG Garantia, A 7002 e DM 309. Genetic divergence was evaluated by multivariate procedures: generalized Mahalanobis distance, the grouping optimization method of Tocher, nearest neighbor and the technique of canonical variables. It was evaluated the following characteristics: grain production per plant, number of seeds per pod, number of pods per plant, number of days for blooming; number of days for maturation, plant height and height of first pod insertion. The methods of optimization of Tocher, nearest neighbor and graphic dispersion of the canonical variables were consistent with each other. The characteristics number of days for the maturation (39.49%), weigh of 10...

O cultivo de cebola no país concentra-se na região Centro Sul, porém com o desenvolvimento de cultivares adaptadas, novas áreas de plantio podem se tornar as atuais áreas de plantio existentes. Objetivouse com esse trabalho avaliar três épocas de plantio de cultivares de cebola na região Centro Sul do estado do Tocantins. Foram avaliados três cultivares em três épocas distintas, sendo estas 26 de maio, 26 de junho e 26 de julho. As mudas foram obtidas em bandejas de 200 células e transplantadas 35 dias após a germinação para canteiros no espaçamento de 0,15 m x 0,10 m. Em cada época de plantio, o delineamento experimental utilizado foi blocos ao acaso, com quatro repetições. Foram avaliadas as características produtividade (t ha -1 ), peso médio dos bulbos (gramas), pungência, ciclo (dias). A cultivar Nun 1205 apresentou a maior produtividade (49,02 t ha -1 ) e peso médio de bulbo (163,41 gramas), sendo a segunda época de plantio superior as demais, em relação a produtividade (56,50 t ha -1 ) e peso médio de bulbo (183,33 gramas). Em relação aos teores de ácido pirúvico a cultivar Cimarron diferiu dos demais, sendo todas as três cultivares classificadas com pungência média a alta. Todos as cultivares apresentaram ciclos precoce.

O trabalho teve por objetivo avaliar a similaridade genética entre progênies de meio-irmãos de batata-doce com potencial para produção de etanol com base em caracteres agronômicos. Foram avaliadas 96 progênies de meios-irmãos obtidas de campo de policruzamento de 10 cultivares (Ana Clara, Amanda, Duda, Carolina Vitória, Júlia, Bárbara, Lívia, Marcela, Izabela e Beatriz) com aptidão para produção de etanol e quatro cultivares testemunhas (‘Marcela’, ‘Júlia’, ‘Ana Clara’ e ‘Carolina Vitória’). A colheita foi realizada 150 dias após o plantio e os caracteres avaliados foram: produtividade total e massa média das raízes; teor de massa seca e incidência de danos provocados por insetos do solo. As progênies BDFMI#35, BDFMI#51, BDFMI#49, BDFMI#58, BDFMI#76 e BDFMI#10 foram superiores em produtividade (médias entre 63,2 t ha-1 e 46,0 t ha-1), sendo recomendadas para exploração per se na região alvo do estudo. Houve a formação de onze grupos de dissimilaridade, o que evidencia variabilidade ...

Resumo: O presente trabalho teve como objetivo analisar o desempenho dos candidatos do curso de Matemática na prova de matemática, do Vestibular de Primavera-2008 da Universidade Estadual do Centro-Oeste, UNICENTRO. Foi analisado o desempenho médio de um grupo de candidatos escolhidos aleatoriamente, verifi cando os acertos em cada questão e, também, se existe diferença no desempenho entre candidatos que fi zeram opção pelos turnos da manhã e da noite, considerando a menor concorrência para o turno da manhã. Palavras-chave: desempenho no vestibular; análise estatística; estudantes de matemática.

The objective of this work was to evaluate the feasibility of simultaneous use of the ripening mutant (nor(A) or rin) and color enhancing mutant genes (og(c) and/or hp) in tomato hybrids with different genotypic backgrounds and genotype combinations. The trial was set up in a plastic house, with in RCB design with 20 genotypes and 3 replications. Ripening mutant genotypes nor(+)/nor(A) and rin(+)/rin reduced early yields, but not total yields. Genotypes bearing one or more mutants nor(A), rin, og(c) or hp showed improved shelf life in comparison to that of normal genotypes. The constitution rin(+)/rin showed the poorest internal color among the genotypes tested. There was a positive effect of og(c+)/og(c), og(c)/og(c) and/or hp(+)/hp on the internal fruit color of normal nor(+)/nor(A) and rin(+)/rin genotypes, but the effect in rin(+)/rin genotypes was not enough as to insure a final color similar to that of normal genotypes. Genotypic constitutions og(c+)/og(c), and og(c)/og(c), in...

A alface é uma hortaliça consumida principalmente na forma in natura, contem boas quantidades de vitaminas A, B1, B2, B6 e C. O fornecimento adequado de nutrientes é fundamental, sendo que o N para a alface está diretamente associado as características vegetativas, reprodutivas e morfológicas. O experimento foi conduzido no setor de Olericultura da Universidade Federal do Tocantins (UFT), na cidade de Gurupi. Foram utilizadas duas cultivares, Elba e Verônica. As mudas foram produzidas em bandejas de isopor de 128 células. Aos 27 dias após o transplantio, foram avaliadas as seguintes características: Massa fresca aérea (MFA) - Obtida com a pesagem das plantas coletadas; Número de folhas totais (NFT) - Através da contagem das folhas das planta; Diâmetro da cabeça (DC) - Obtido com auxilio de uma régua; Massa seca aérea (MSA) – Obtida através da secagem da massa verde em estufa a 60° C, ate atingir peso constante, quando as amostras foram pesadas novamente. Podemos destacar que a cv. E...

O objetivo deste trabalho foi avaliar a viabilidade do emprego isolado e simultâneo dos mutantes rin, norA, og c e hp em heterozigose, em genótipos de tomateiro, visando à melhoria da qualidade pós-colheita dos frutos. Foram avaliados 18 genótipos que diferem quanto às combinações entre estes locos em dois diferentes backgrounds (FloraDade e background experimental). Contrastes não ortogonais foram estabelecidos para quantificar os efeitos dos alelos mutantes, isoladamente ou combinados em um mesmo genótipo, em dois backgrounds, sobre a produção total e produção precoce de frutos, massa média, firmeza, coloração externa, teores de licopeno e betacaroteno dos frutos. Os alelos norA e rin em heterozigose, no background FloraDade, desaceleraram a taxa de perda de firmeza e reduziram os teores de licopeno e betacaroteno nos frutos maduros. As combinações heterozigotas entre o mutante rin e os mutantes norA, og c e hp aumentaram a firmeza dos frutos. O efeito do genótipo rin+/rin nor+/no...

Kemampuan mahasiswa dalam menerapkan konsep berkomunikasi bisnis pada aktivitas perkuliahan masih rendah. Rendahnya pemahaman konsep peserta didik disebabkan karena pembelajaran yang diterapkan dosen masih bersifat lecturer centered. Dosen hanya menyampaikan materi pembelajaran secara satu arah. Aktivitas belajar mahasiswa menjadi tidak bervariasi, hanya mendengarkan informasi dari dosen saja. Penelitian ini bertujuan untuk mengkaji penerapan pembelajaran berbasis masalah (problem based-learning) pada pembelajaran mata kuliah komunikasi bisnis untuk meningkatkan kemampuan berpikir kritis dan kreatif mahasiswa. Subjek dalam penelitian ini adalah mahasiswa program studi Manajemen Fakultas Ekonomi dan Bisnis Institut Informatika dan Bisnis Darmajaya. Penelitian dilaksanakan pada bulan Maret sampai dengan bulan Juni 2022. Data penelitian diambil dengan metode tindakan kelas dan survey. Metode analisis data yang digunakan adalah metode deskriptif. Persepsi mahasiswa diukur melalui 7 aspe...

L’articolo presenta i principali risultati di esperimenti eseguiti su nodi trave-pilastro innovativi realizzati con struttura composta acciaio e calcestruzzo. Trattasi di cinque prove in cui altrettanti nodi a due vie in scala reale sono sottoposti a spostamenti pseudo-statici di tipo ciclico tali da indurre una condizione di sollecitazione di tipo sismico. Quattro nodi hanno le travi di tipologia mista acciaio e calcestruzzo ed un nodo e interamente in calcestruzzo armato normale per stabilire utili confronti. Per quanto riguarda i primi quattro, due nodi hanno i pilastri in c.a., un nodo e realizzato con pilastro con camicia di acciaio di sezione quadrata ed infine un nodo ha anche i pilastri in struttura reticolare mista. I risultati ottenuti sono analizzati criticamente e confrontati tra loro per poter trarre utili conclusioni sulla duttilita e sulla resistenza dei nodi innovativi nei confronti delle sollecitazioni di natura sismica.

The adjustment of grid steps which guarantees that particles methods yield no numerical diffusion inevitably induces overshooting errors in the solution of the parabolic partial differential equations with space variable coefficients. In this paper we give an evaluation of the overshooting errors of the "global random walk" algorithm (GRW), a computational efficient method used in simulations for transport in environmental problems. The evaluation is performed by comparisons between the GRW solutions and those of the "biased global random walk" algorithm (BGRW), a cellular automaton, which is computationally more expensive but is also free of overshooting errors. The reference problem was the diffusive transport in a random velocity field, a model for the transport of the contaminant solutes in groundwater. The evaluation reveals that, for an optimum choice of the parameters, GRW results for time intervals of practical interest lie in ranges of acceptable precisi...

In a first approximation, the Earth's interior has an isotropic structure with a spherical symmetry. Over the last decades the geophysical observations have revealed, at different spatial scales, the existence of several perturbations from this basic structure. In this paper we discuss the hemispheric perturbations induced to this basic structure if the inner core is displaced from the center of mass of the Earth. Using numerical simulations of the observed hemispheric asymmetry of the seismic waves traveling through the upper inner core, with faster arrival times and higher attenuation in the Eastern Hemisphere, we estimate that the present position of the inner core is shifted by tens of kilometers from the Earth's center eastward in the equatorial plane. If the only forces acting on the inner core were the gravitational forces, then its equilibrium position would be at the Earth's center and the estimated displacement would not be possible. We conjecture that, due to interactions with the flow and the magnetic field inside the outer core, the inner core is in a permanent chaotic motion. To support this hypothesis we analyze more than ten different geophysical phenomena consistent with an inner core motion dominated by time scales from hundreds to thousands of years.

Plasmonic nanomaterials have tremendous potential to improve the tumor specificity of traditional cancer ablation practices, yet little effort has been directed toward quantitatively understanding their photothermal energy conversion in tumor tissues. In the present work, we develop a predictive model for plasmonic nanomaterial assisted tumor destruction under extracorporeal laser irradiation. Instead of appealing to heuristically based laser intensification models with tunable, tissue absorption and scattering coefficients, we consider fundamental characteristics of optoelectrothermal energy conversion and heat dissipation for plasmonic nanomaterials within living tumor tissues to construct a simulation tool that accurately reproduces our experimental findings, including aspects of delayed time-temperature characteristics. We believe the comprehensive modeling strategy outlined here provides a groundwork for the development of anticipatory therapeutic planning tools with individual...

We derive the gas dynamics equations considering changes of velocity distribution function on the scale of a molecule free path. We define the molecule velocity distribution function in a specific form so that only molecule velocities after intermolecular collisions in a chosen fixed volume are taken into account. The obtained equations differ from the well-known Navier-Stoks equations and contain the new terms. The continuity equation includes the second derivatives of dynamical viscosity. The equation of momentum conservation does not include the volume viscosity and the equation of energy conservation describes the transformation of gas mass velocity into the gas thermal energy. One can expect that these new equations of motion allow to construct a description of macroscopic physical phenomena in more complicated situations than the standard gas dynamics equations do.

Pemrograman terpisah adalah pendekatan yang digunakan untuk memecahkan masalah nonlinier dengan Metode Simplex. Metode ini terbukti dalam memecahkan masalah nonlinier, yang sampai sekarang tidak memiliki metode seperti dalam masalah pemrograman linier standar. Tulisan ini mencoba membandingkan proses dan hasil dari pendekatan Pemrograman terpisah dengan Kondisi Kuhn-Tucker. Terbukti bahwa keduanya memberikan hasil yang serupa, tetapi dengan cara yang berbeda. Pendekatan Pemrograman terpisah sebaiknya digunakan untuk memecahkan masalah nonlinier yang memiliki kesulitan ketika diselesaikan dengan Pendekatan Kondisi Kuhn-Tucker.

Pemrograman Linier Parametrik merupakan model pengembangan analisis sensitivitas dimana koefisien input berubah secara simultan. Model ini mengembangkan pemecahan masalah dimana nilai koefisien input tidak diketahui dengan pasti, namun dapat dilakukan estimasi dalam interval tertentu sesuai dengan tingkat kepercayaan yang diharapkan. Dalam tulisan ini diuraikan manfaat Pemrograman Linier Parametrik untuk menganalisis dampak fluktuasi koefisien fungsi objektif dan konstanta terhadap solusi optimal. Terbukti bahwa perubahan koefisien input dalam interval tertentu tidak mengubah solusi optimal yang telah diperoleh sebelumnya.

Sebuah perusahaan manufaktur yang bergerak pada industri makanan di Indonesia masih menggunakan mesin manual dalam proses packing. Proses ini membutuhkan lebih banyak tenaga kerja dan masih terdapat kondisi bottleneck. Perusahaan perlu meningkatkan efisiensi lini produksi, terutama pada packing line. Penelitian ini bertujuan untuk menentukan jumlah dari stasiun kerja optimal dengan menggunakan metode terbaik, dan menentukan perencanaan yang optimal dari packing line. Kriteria evaluasi untuk metode terbaik adalah output dan proses, dan kriteria evaluasi untuk garis keseimbangan adalah garis efisiensi dan jumlah stasiun kerja. Empat pendekatan berbeda yang digunakan dalam penelitian ini adalah pendekatan analitis (Branch and Bound method), pendekatan heuristik (Rank Position Weight System method), pendekatan metaheuristic (Ant Colony Optimization method) dan pendekatan simulasi (metode COMSOAL). Hasil penelitian menunjukkan bahwa efisiensi jalur meningkat 12% dan jumlah stasiun kerja menurun menjadi 11 stasiun kerja. Perusahaan dapat mengurangi biaya tenaga kerja sebesar Rp 6.006.000 per bulan dengan perencanaan yang optimal.

Abstrak   Seiring dengan terjadinya perubahan variasi permintaan pada setiap periode untuk produksi tertentu menyebabkan perusahaan harus memiliki rencana produksi yang berbeda setiap periode sesuai dengan kapasitas produksi. Untuk membantu dalam melakukan perancangan volume produksi yang optimal, diperlukan metode yang sesuai. Pada kasus ini, line -4 MV plant PT X memproduksi enam jenis kabel twisted dengan jumlah produksi dan profit yang berbeda-beda. Metode Theory of constraints (TOC) dapat mengidentifikasi masalah produksi, terutama dalam hal kendala kapasitas. Metode ini dilengkapi dengan Linear Programming dalam membantu merancang volume produksi optimal dengan profit maksimum. Dari hasil pengolahan data ditemukan kendala pada semua proses dan dari hasil perhitungan Linear Programming menggunakan software Win-QSB dapat diketahui volume produksi optimal, yakni NFA2X 2x16 sebanyak 52,7 km, NFA2X 4x16 sebanyak 0 km, NFA2X 4x25 sebanyak 10 km, NFA2X-T 3x70+50 sebanyak 140,5 km, A...

Received: June 11, 2019 Revised: July 22, 2019 Accepted: July 30, 2019 Beberapa tahun terakhir ini, minimisasi biaya logistik dan transportasi menjadi hal yang penting pada perusahaan manufaktur untuk meningkatkan profit. Salah satu hal yang dilakukan untuk mengurangi biaya logistik dan transportasi adalah dengan cara mengoptimalkan rute pengambilan atau pengangkutan komponen dari setiap supplier. Pengoptimalan rute dengan tujuan untuk meminimalkan total biaya transportasi merupakan permasalahan yang sering ditemukan pada Vehicle Routing Problem (VRP). Problem Capacitated Vehicle Routing with Time Windows (CVRPTW) merupakan salah satu varian dari VRP yang mempertimbangkan kapasitas kendaraan dan jangka waktu pelayanan tiap kendaraan. CVRPTW merupakan permasalahan NonPolynomial Hard (NP-Hard) yang memerlukan algoritma yang efisien dan efektif dalam menyelesaikan permasalahan yang terjadi di perusahaan otomotif ini. Penelitian ini menggunakan algoritma Ant Colony Optimization (ACO) de...

Pemilihan supplier menjadi hal yang penting bagi perusahaan. Hingga saat ini banyak perusahaan yang menentukan supplier berdasarkan intuisi, tidak disertai dengan kriteria evaluasi dan metode evaluasi yang rasional dan terukur. Akibatnya perusahaan sering tidak mendapatkan supplier terbaik. Faktor kekerabatan yang sering dijadikan pertimbangan dalam pemilihan supplier pada akhirnya dapat merugikan perusahaan. Penelitian ini mengusulkan penggunaan Metode AHP-TOPSIS dan Metode AHP-MPE untuk mengevaluasi supplier paper-bag di CV. Fresh Reborn merupakan sebuah perusahaan yang bergerak dalam bidang layanan reparasi berbagai produk personal, seperti tas, sepatu, dompet dan produk sejenisnya. Dengan meminta pendapat pimpinan perusahaan untuk evaluasi tiga supplier potensial ditemukan bahwa Metode AHP-TOPSIS dan AHP-MPE dapat digunakan untuk membuat peringkat ketiga supplier tersebut. Dari penelitian ini ditemukan bahwa kedua metode memberikan hasil pemeringkatan yang sama.

Köprülerin yapısal güvenliği açısından oldukça önemli olan köprü ayaklarının tasarımının, hidrolik açıdan da analizi gerekmektedir. Köprü ayakları, akım alanını daraltarak köprü membaında kabarmalara ve beraberinde taşkınlara neden olabilmektedir. Dolayısıyla farklı akım koşullarında köprü ayaklarının etkisi altında oluşan su yüzü profillerinin ve kabarma miktarlarının deneysel ve sayısal çalışmalar ışığı altında en doğru şekilde belirlenmesi köprü hidrolik tasarımının önemli bir bölümünü oluşturmaktadır. Bu çalışmada, farklı enkesitlerdeki köprü ayaklarının ve verevlik açısının köprü etrafında oluşan su yüzü profili ve köprü membaındaki kabarma miktarı üzerindeki etkileri deneysel ve sayısal olarak araştırılmıştır. Deneysel çalışmalar Niğde Ömer Halisdemir Üniversitesi Mühendislik Fakültesi İnşaat Mühendisliği Bölümü Hidrolik Laboratuvarında bulunan ve boyutları 10x0.309x0.45 m olan deneysel kanal üzerinde yürütülmüştür. Yapılan deneysel çalışmalarda 4 farklı köprü ayağı tipi (kare...

Köprülerin yapısal güvenliği açısından oldukça önemli olan köprü ayaklarının tasarımının, hidrolik açıdan da analizi gerekmektedir. Köprü ayakları, akım alanını daraltarak köprü membaında kabarmalara ve beraberinde taşkınlara neden olabilmektedir. Dolayısıyla farklı akım koşullarında köprü ayaklarının etkisi altında oluşan su yüzü profillerinin ve kabarma miktarlarının deneysel ve sayısal çalışmalar ışığı altında en doğru şekilde belirlenmesi köprü hidrolik tasarımının önemli bir bölümünü oluşturmaktadır. Bu çalışmada, farklı enkesitlerdeki köprü ayaklarının ve verevlik açısının köprü etrafında oluşan su yüzü profili ve köprü membaındaki kabarma miktarı üzerindeki etkileri deneysel ve sayısal olarak araştırılmıştır. Deneysel çalışmalar Niğde Ömer Halisdemir Üniversitesi Mühendislik Fakültesi İnşaat Mühendisliği Bölümü Hidrolik Laboratuvarında bulunan ve boyutları 10x0.309x0.45 m olan deneysel kanal üzerinde yürütülmüştür. Yapılan deneysel çalışmalarda 4 farklı köprü ayağı tipi (kare...

Background: A new Ultra performance liquid chromatographic analytical method was developed and validated for estimation of Quercetin in bulk powder. The reverse phase chromatographic elution using UPLC was carried out in gradient mode on C-18 column (Phenomenex Luna 5 µm, 150 mm X 4.6 mm) as stationary phase utilizing a mobile phase composed of Acetonitrile: 0.1 % formic acid buffer (50:50 v/v) with a flow rate of 1 ml/min and injection volume of 10µl.  The analysis was performed at temperature of 400C and detection of eluent was carried out using photo diode array at 371 nm. The newly developed Ultra performance liquid chromatography method was validated in terms of linearity and range, system suitability, specificity, precision, sensitivity, robustness, ruggedness and accuracy as per ICH guidelines. Results: The retention time of quercetin was found to be at 3.9 min with total run time of analysis is 7 minutes. The linearity was observed between the concentration ranges from 0.5 t...

Dalam penelitian ini penulis menganalisis tingkat kepuasan pengunjung Daya Tarik Wisata Kebun Raya Balikpapan, penelitian ini bertujuan untuk mengetahui tingkat kepuasan pengunjung berdasarkan faktor-faktor yang mempengaruhinya serta menentukan faktor yang paling dominan yang mempengaruhi tingkat kepuasan pengunjung wisata. Tingkat kepuasan pengunjung dibatasi pada 6 faktor yang berpengaruh yaitu pemandangan, aksesbilitas/kemudahan , keamanan atau kenyamanan, kondisi dan ketersediaan fasilitas, kondisi jalan, serta pelayanan informasi yang terdapat pada Obyek Wisata Kebun Raya Balikpapan. Metode yang digunakan yaitu metode penelitian deskriptif kuantitatif berdasarkan data yang didapatkan melalui kuisioner. Teknik analisis data yang digunakan yaitu analisis kuantitatif mean aritmatik untuk mengetahui tingkat kepuasan pengunjung objek wisata kebun raya Balikpapan. Hasil dari penelitian ini menunjukkan bahwa terdapat enam faktor yang mempengaruhi tingkat kepuasan pengunjung Daya Tarik...

Music is traditionally considered as a temporal art. At the same time, a musical work supposes organisation, unity, continuity. These are attributes of spatiality. By consequence, we are talking in music about a special kind of space -not surfaces or volumes, but a metaphorical one, which we call here the virtual musical space. It is important not only to admit its presence among the musical language elements, but especially to comprehend its structure, and its influence in the modern forms of art.

The effect of human fetal heart geometry and anisotropy on anatomy induced drift and self-termination of cardiac re-entry is studied here in MRI based 2D slice and 3D whole heart computer simulations. Isotropic and anisotropic models of 20 weeks of gestational age human fetal heart obtained from 100 µm voxel diffusion tensor MRI data sets were used in the computer simulations. The fiber orientation angles of the heart were obtained from the orientation of the DT-MRI primary eigenvectors. In a spatially homogeneous electrophysiological monodomain model with the DT-MRI based heart geometries, cardiac re-entry was initiated at a prescribed location in a 2D slice, and in the 3D whole heart anatomy models. Excitation was described by simplified FitzHugh-Nagumo kinetics. In a slice of the heart, with propagation velocity twice as fast along the fibers than across the fibers, DT-MRI based fiber anisotropy changes the re-entry dynamics from pinned to an anatomical re-entry. In the 3D whole heart models, the fiber anisotropy changes cardiac re-entry dynamics from a persistent re-entry to the re-entry self-termination. The self-termination time depends on the re-entry's initial position. In all the simulations with the DT-MRI based cardiac geometry, the anisotropy of the myocardial tissue shortens the time to re-entry self-termination several folds. The numerical simulations depend on the validity of the DT-MRI data set used. The ventricular wall showed the characteristic transmural rotation of the helix angle of the developed mammalian heart, while the fiber orientation in the atria was irregular.