2,912 research outputs found
Discovery Learning Experiments in a New Machine Design Laboratory
A new Machine Design Laboratory at Marquette University has been created to foster student exploration with hardware and real-world systems. The Laboratory incorporates areas for teaching and training, and has been designed to promote “hands-on” and “minds-on” learning. It reflects the spirit of transformational learning that is a theme in the College of Engineering.
The goal was to create discovery learning oriented experiments for a required junior-level “Design of Machine Elements” course in mechanical engineering that would give students practical experiences and expose them to physical hardware, actual tools, and real-world design challenges. In the experiments students face a range of real-world tasks: identify and select components, measure parameters (dimensions, speed, force), distinguish between normal and used (worn) components and between proper and abnormal behavior, reverse engineer systems, and justify design choices. The experiments serve to motivate the theory and spark interest in the subject of machine design.
This paper presents details of the experiments and summarizes student reactions and our experiences in the Machine Design Laboratory. In addition, the paper provides some insights for others who may wish to develop similar types of experiments
Trend Analyses of the Abundances of Atmospheric Molecules
A new line list for the A3Π - X3Σ- electronic transition of NH has been prepared using line positions from the literature and calculated line intensities. High level ab initio calculations were performed with the MOLPRO program to obtain the A - X transition dipole moment function. Potential energy curves and line strengths were calculated with Le Roy\u27s RKR1 and LEVEL programs. Line intensities and Einstein A values were calculated with Western\u27s PGOPHER program after converting the Hund\u27s case (b) output of LEVEL to Hund\u27s case (a) input needed for PGOPHER. The Herman- Wallis eect is included in the Einstein A calculations of the bands for the levels with v\u27 = 0 - 2 and v\u27\u27 = 0 - 6.
Spectra of pure isobutane were recorded at high temperature in the CH stretching region (2700-3100 cm-1) by high resolution Fourier transform spectroscopy. Isobutane absorption cross sections were determined for six temperatures from 273 K to 723 K. Integrated cross sections were compared with cross section data from the Pacific Northwest National Laboratory (PNNL) database.
Near global ozone isotopologue distributions have been determined from infrared solar occultation measurements of the Atmospheric Chemistry Experiment (ACE) satellite mission. ACE measurements are made with a high resolution Fourier transform spectrometer (ACE-FTS). Annual and seasonal latitudinal fractionation (δ value) distributions of the ozone isotopologues 16O16O18O, 16O18O16O and 16O17O16O were obtained. Asymmetric ozone (16O16O18O) shows higher fractionation compared to symmetric ozone (16O18O16O). The maximum ozone fractionation occurs in the tropical stratosphere as expected from the contribution of photolysis to the enrichment of heavy isotopologues. An enhancement of the heavy ozone isotopologues is also seen in the upper stratosphere of the Antarctic polar vortex.
A new version of ACE-FTS routine data product (4.0) provides near global VMR altitude profile of low altitude CO2 on a 1 km grid from 5-18 km. An initial evaluation of these data has been carried out for the years 2004-2017 and for the month May in the 55°-70°S latitude range. The ACE-FTS data has been compared with ground-based measurements at Macquarie Island, the South Pole, the CarbonTracker 2017 model and G. Toon\u27s empirical model. Trends agree, but ACE-FTS data has a low bias at 5.5 and 6.5 km in altitude.
The Montreal Protocol banned the production of major ozone depleting substances such as chloro uorocarbons (CFCs) to protect the Earth\u27s ozone layer. These halogenated compounds are inert in the troposphere and ultimately converted to HCl in the upper atmosphere. Therefore, by measuring stratospheric HCl concentrations, the effectiveness of the Montreal Protocol can be evaluated. After banning the production of CFCs, the increased production and emissions of CFC-replacement hydroflourocarbons (HFCs) has caused a dramatic increase in their atmospheric abundances. Although these HFCs do not contribute directly to the depletion of the ozone layer because they contain no chlorine, they are powerful greenhouse gases with large global warming potentials. In January 2019, the Kigali Amendment to the Montreal Protocol came into force to phase out long-lived HFCs. The two most abundant HFCs in the atmosphere, HFC-134a (CF3CH2F) and HFC-23 (CHF3), are measured from orbit by ACE-FTS. These measurements will be useful for monitoring the Kigali Amendment to the Montreal Protocol. A trend analysis of the ACE-FTS near-global measurements confirms the rapid increase in HFC-134a (4.9+/-0:1 ppt per year) and HFC-23 (0.75+/-0:02 ppt per year) volume mixing ratios (VMRs). A trend analysis has been carried out for HCl volume mixing ratio profiles provided by ACE-FTS as well; and the upper stratospheric HCl VMR time series of ACE-FTS shows a linear trend of -4.8+/-0.2%/decade for 2004-2017, highlighting the continuing success of the Montreal Protocol
Using Remote Access for Sharing Experiences in a Machine Design Laboratory
A new Machine Design Laboratory at Marquette University has been created to foster student exploration and promote “hands-on” and “minds-on” learning. Laboratory experiments have been developed to give students practical experiences and expose them to physical hardware, actual tools, and design challenges. Students face a range of real-world tasks: identify and select components, measure parameters (dimensions, speed, force), distinguish between normal and used (worn) components and between proper and abnormal behavior, reverse engineer systems, and justify design choices. The experiments serve to motivate the theory, spark interest, and promote discovery learning in the subject of machine design.
This paper presents details of the experiments in the Machine Design Laboratory and then explores the feasibility of sharing some of the experiences with students at other institutions through remote access technologies. The paper proposes steps towards achieving this goal and raises issues to be addressed for a pilot-study offering machine design experiences to students globally who have access to the internet
ANALISIS SISTEM INFORMASI AKUNTANSI PADA CV. SURYA KENCANA
Penelitian ini bertujuan untuk menganalisis sistem informasi akuntasi yang ada dan memberikan gambarannya kepada CV. Surya Kencana. Penelitian ini menggunakan metode kualitatif dengan menggunakan dua jenis data yaitu data primer dan data sekunder. Dalam melakukan penelitian, penulis menggunakan tiga teknik pengumpulan data yaitu dengan wawancara, observasi atau pengamatan, dan dokumentasi yang dianalisis dengan metode analisis data kualitatif. Hasil dalam penelitian ini berdasarkan analisis yang telah dilakukan menjelaskan bahwa perusahaan belum memiliki sistem informasi akuntansi yang terintegrasi dengan baik, tidak adanya otorisasi yang terdapat dalam gudang atas jumlah barang masuk dan keluar yang menyebabkan terdapatnya selisih stok fisik persediaan yang ada pada gudang dengan yang tercatat pada sistem
A neuro-inspired system for online learning and recognition of parallel spike trains, based on spike latency and heterosynaptic STDP
Humans perform remarkably well in many cognitive tasks including pattern
recognition. However, the neuronal mechanisms underlying this process are not
well understood. Nevertheless, artificial neural networks, inspired in brain
circuits, have been designed and used to tackle spatio-temporal pattern
recognition tasks. In this paper we present a multineuronal spike pattern
detection structure able to autonomously implement online learning and
recognition of parallel spike sequences (i.e., sequences of pulses belonging to
different neurons/neural ensembles). The operating principle of this structure
is based on two spiking/synaptic neurocomputational characteristics: spike
latency, that enables neurons to fire spikes with a certain delay and
heterosynaptic plasticity, that allows the own regulation of synaptic weights.
From the perspective of the information representation, the structure allows
mapping a spatio-temporal stimulus into a multidimensional, temporal, feature
space. In this space, the parameter coordinate and the time at which a neuron
fires represent one specific feature. In this sense, each feature can be
considered to span a single temporal axis. We applied our proposed scheme to
experimental data obtained from a motor inhibitory cognitive task. The test
exhibits good classification performance, indicating the adequateness of our
approach. In addition to its effectiveness, its simplicity and low
computational cost suggest a large scale implementation for real time
recognition applications in several areas, such as brain computer interface,
personal biometrics authentication or early detection of diseases.Comment: Submitted to Frontiers in Neuroscienc
Gradient-Descent Quantum Process Tomography by Learning Kraus Operators
We perform quantum process tomography (QPT) for both discrete- and continuous-variable quantum systems by learning a process representation using Kraus operators. The Kraus form ensures that the reconstructed process is completely positive. To make the process trace preserving, we use a constrained gradient-descent (GD) approach on the so-called Stiefel manifold during optimization to obtain the Kraus operators. Our ansatz uses a few Kraus operators to avoid direct estimation of large process matrices, e.g., the Choi matrix, for low-rank quantum processes. The GD-QPT matches the performance of both compressed-sensing (CS) and projected least-squares (PLS) QPT in benchmarks with two-qubit random processes, but shines by combining the best features of these two methods. Similar to CS (but unlike PLS), GD-QPT can reconstruct a process from just a small number of random measurements, and similar to PLS (but unlike CS) it also works for larger system sizes, up to at least five qubits. We envisage that the data-driven approach of GD-QPT can become a practical tool that greatly reduces the cost and computational effort for QPT in intermediate-scale quantum systems
Microarray tools to unveil viral-microbe interactions in nature
The interactions between viruses and their microbial hosts play a central role in the control of microbial communities in nature. However, the study of such interactions within the uncultured majority is technically very challenging. Here, we review how microarray tools can be used to analyze the interactions between viruses and their microbial hosts in nature, away from laboratory pure culture-based models. We show examples of how DNA arrays have been used to study the expression of viral assemblages in natural samples, and to assign viruses to hosts within uncultured communities. Finally, we briefly discuss the possibilities of protein and glycan arrays to gain insight into the ways microbes interact with their viruses.Our current studies with viral microarrays are supported by projects CGL2012-39627-C03-01 (to Josefa Antón) and AYA2011-24803 (to Víctor Parro) of the Spanish Ministry of Science and Innovation, which are co-financed with FEDER support from the European Union
Plantas silvestres comestibles utilizadas en poblaciones rurales de la Provincia de La Rioja (Argentina).
En este trabajo se indaga sobre el conocimiento popular y el uso de plantas silvestres utilizadas en la alimentación humana en cuatro poblados rurales pedemontanos de La Rioja. Se registraron las especies alimenticias de uso actual, las partes de las plantas utilizadas, las formas de preparación de los alimentos,
las formas de conservación de los productos y el lugar y época de recolección para cada una. Se entrevistaron ocho informantes clave, los que mencionaron un total de 38 nombres locales de plantas alimenticias silvestres. En la actualidad, el 20% de las especies mencionadas se han dejado de utilizar, el 53% se utiliza ocasionalmente y sólo el 27% se utiliza frecuentemente. Las partes de las plantas más consumidas son los frutos y hojas, siendo menos frecuente el consumo de tallos y flores. Las formas de preparación más utilizadas son la cocción, la infusión y el consumo fresco. El modo de conservación más frecuente es a través
del secado de frutos y ramas, siguiéndole en importancia la conservación de productos en botellas. Muchas de las plantas silvestres alimenticias son recolectadas en las cercanías de las viviendas y en el campo, en general durante el verano. Los pobladores no utilizan el total de plantas alimenticias que conocen,
lo cual podría llevar a la pérdida gradual del conocimiento local sobre los recursos disponibles.Fil: Biurrum, Elda. Universidad Nacional de la Rioja. Sede Chamical; ArgentinaFil: Galetto, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Anton, Ana Maria Ramona. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Santiago del Estero. Universidad Nacional de Santiago del Estero. Centro de Investigaciones y Transferencia de Santiago del Estero; ArgentinaFil: Biurrum, Fernando. Universidad Nacional de la Rioja. Sede Chamical; Argentin
OZONE ISOTOPOLOGUE MEASUREMENTS FROM THE ATMOSPHERIC CHEMISTRY EXPERIMENT (ACE)
Near global ozone isotopologue distributions have been determined from infrared solar occultation measurements of the Atmospheric Chemistry Experiment (ACE) satellite mission. ACE measurements are made with a high resolution Fourier transform spectrometer. Annual and seasonal latitudinal fractionation ( value) distributions of the ozone isotopologues OOO, OOO and OOO were obtained. Asymmetric ozone (OOO) shows higher fractionation compared to symmetric ozone (OOO). The maximum ozone fractionation occurs in the tropical stratosphere as expected. An enhancement of the heavy ozone isotopologues is also seen in the Antarctic polar vortex
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