5,185 research outputs found

    Sequence distribution studies of dichloroprotoanemonin-methyl methacrylate copolymers

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    Chloride elimination and ultraviolet bands in dichloroprotoanemonin/methyl methacrylate copolymer

    Penerapan Biaya Kualitas Untuk Meningkatkan Efisiensi Produksi Pada Dolphin Donut Bakery Manado

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    Perkembangan dan kompetisi dalam dunia bisnis menuntut Perusahaan untuk menghasilkan produk yang berkualitas. Peningkatan kualitas produk tersebut, akan menimbulkan biaya yang disebut biaya kualitas. Tujuan dari penelitian ini untuk mengetahui penerapan biaya kualitas dalam meningkatkan efisiensi produksi pada Dolphin Donut Bakery. Metode yang digunakan yaitu metode deskriptif kuantitatif yang berusaha mendeskripsikan dan menginterpretasikan tentang biaya kualitas. Unsur-unsur biaya kualitas pada umumnya ada empat akan tetapi biaya kualitas yang terdapat pada Dolphin Donut Bakery ada tiga unsur biaya kualitas yaitu biaya pencegahan, biaya penilaian, biaya kegagalan internal, sedangkan biaya kegagalan eksternal tidak terdapat pada Perusahaan. Hasil penelitian menunjukan bahwa biaya kualitas yaitu biaya pemeriksaan bahan baku dan pembantu yang termasuk dalam biaya penilaian dinaikan, karena biaya ini merupakan biaya terkecil dari semua unsur biaya kualitas yang ada di Dolphin Donut Bakery. Kenaikan biaya ini dimaksudkan agar supaya kualitas produk yang dihasilkan Dolphin Donut Bakery juga meningkat dengan asumsi bahwa dengan menambah jumlah karyawan pada saat pemeriksaan bahan baku dan pembantu, maka kemungkinan adanya bahan baku yang berkualitas rendah menurun sehingga produk yang dihasilkan memiliki kualitas yang lebih baik dan akan berdampak pada jumlah penjualan yang naik. Hal ini juga berpengaruh terhadap efisiensi produksi yang meningkat karena kualitas naik diikuti jumlah konsumen bertambah

    Satellite laser ranging work at the Goddard Space Flight Center

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    Laser ranging systems, their range and accuracy capabilities, and planned improvements for future systems are discussed, the systems include one fixed and two mobile lasers ranging systems. They have demonstrated better than 10 cm accuracy both on a carefully surveyed ground range and in regular satellite ranging operations. They are capable of ranging to all currently launched retroreflector equipped satellites with the exception of Timation III. A third mobile system is discussed which will be accurate to better than 5 cm and will be capable of ranging to distant satellites such as Timation III and LAGEOS

    Optimal Scheduling Using Branch and Bound with SPIN 4.0

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    The use of model checkers to solve discrete optimisation problems is appealing. A model checker can first be used to verify that the model of the problem is correct. Subsequently, the same model can be used to find an optimal solution for the problem. This paper describes how to apply the new PROMELA primitives of SPIN 4.0 to search effectively for the optimal solution. We show how Branch-and-Bound techniques can be added to the LTL property that is used to find the solution. The LTL property is dynamically changed during the verification. We also show how the syntactical reordering of statements and/or processes in the PROMELA model can improve the search even further. The techniques are illustrated using two running examples: the Travelling Salesman Problem and a job-shop scheduling problem

    Background independence in a nutshell

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    We study how physical information can be extracted from a background independent quantum system. We use an extremely simple `minimalist' system that models a finite region of 3d euclidean quantum spacetime with a single equilateral tetrahedron. We show that the physical information can be expressed as a boundary amplitude. We illustrate how the notions of "evolution" in a boundary proper-time and "vacuum" can be extracted from the background independent dynamics.Comment: 19 pages, 19 figure

    Spitzer Observations of NGC 1333: A Study of Structure and Evolution in a Nearby Embedded Cluster

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    We present a comprehensive analysis of structure in the young, embedded cluster, NGC 1333 using members identified with Spitzer and 2MASS photometry based on their IR-excess emission. In total, 137 members are identified in this way, composed of 39 protostars and 98 more evolved pre-main sequence stars with disks. Of the latter class, four are transition/debris disk candidates. The fraction of exposed pre-main sequence stars with disks is 83% +/- 11%, showing that there is a measurable diskless pre-main sequence population. The sources in each of the Class I and Class II evolutionary states are shown to have very different spatial distributions relative to the distribution of the dense gas in their natal cloud. However, the distribution of nearest neighbor spacings among these two groups of sources are found to be quite similar, with a strong peak at spacings of 0.045 pc. Radial and azimuthal density profiles and surface density maps computed from the identified YSOs show that NGC 1333 is elongated and not strongly centrally concentrated, confirming previous claims in the literature. We interpret these new results as signs of a low velocity dispersion, extremely young cluster that is not in virial equilibrium.Comment: 59 pages, 20 figures, accepted to ApJ, verion with full resolution figures available at http://www.cfa.harvard.edu/~rgutermuth/preprints/gutermuth_ngc1333.pdf . Updated to fix astro-ph figure garblin

    Self-sensing cellulose structures with design-controlled stiffness

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    Robots are often used for sensing and sampling in natural environments. Within this area, soft robots have become increasingly popular for these tasks because their mechanical compliance makes them safer to interact with. Unfortunately, if these robots break while working in vulnerable environments, they create potentially hazardous waste. Consequently, the development of compliant, biodegradable structures for soft, eco-robots is a relevant research area that we explore here. Cellulose is one of the most abundant biodegradable materials on earth, but it is naturally very stiff, which makes it difficult to use in soft robots. Here, we look at both biologically and kirigami inspired structures that can be used to reduce the stiffness of cellulose based parts for soft robots up to a factor of 19 000. To demonstrate this, we build a compliant force and displacement sensing structure from microfibrillated cellulose. We also describe a novel manufacturing technique for these structures, provide mechanical models that allow designers to specify their stiffness, and conclude with a description of our structure's performance

    The Properties of X-ray Luminous Young Stellar Objects in the NGC 1333 and Serpens Embedded Clusters

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    We present Chandra X-ray data of the NGC 1333 embedded cluster, combining these data with existing Chandra data, Sptizer photometry and ground based spectroscopy of both the NGC 1333 & Serpens North clusters to perform a detailed study of the X-ray properties of two of the nearest embedded clusters to the Sun. In NGC 1333, a total of 95 cluster members are detected in X-rays, of which 54 were previously identified with Spitzer. Of the Spitzer sources, we detect 23% of the Class I protostars, 53% of the Flat Spectrum sources, 52% of the Class II, and 50% of the Transition Disk YSOs. Forty-one Class III members of the cluster are identified, bringing the total identified YSO population to 178. The X-ray Luminosity Functions (XLFs) of the NGC 1333 and Serpens clusters are compared to each other and the Orion Nebula Cluster. Based on this comparison, we obtain a new distance for the Serpens cluster of 360+22/-13 pc. The X-ray luminosity was found to depend on the bolometric luminosity as in previous studies of other clusters, and that Lx depends primarily on the stellar surface area. In the NGC 1333 cluster, the Class III sources have a somewhat higher X-ray luminosity for a given surface area. We also find evidence in NGC 1333 for a jump in the X-ray luminosity between spectral types of M0 and K7, we speculate that this may result from the presence of radiative zones in the K-stars. The gas column density vs. extinction in the NGC 1333 was found to be N_H = 0.89 +/- 0.13 x 10^22 A_K, this is lower than expected of the standard ISM but similar to that found previously in the Serpens Cloud Core.Comment: 58 pages, 14 figures, accepted by A
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