84 research outputs found

    Rancang Bangun Access Point Menggunakan Empat Perangkat Nanostation2 Loco (Ns2l) pada Outdoor Hotspot System

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    NanoStation2 Loco (NS2L) adalah salah satu jenis perangkat Access Point dari vendor Perusahaan IT terkemuka Ubiquiti Networks. Kelemahan dari perangkat ini adalah jenis antena terintegrasi yang digunakan yaitu directional antenna dengan cakupan 60°, maka arah pola pancaran sinyal cenderung diarahkan dan tidak dapat menjangkau client yang berada jauh di belakang perangkat. Dalam tulisan ini akan dibahas mengenai bagaimana merancang bangun untuk mengimplementasi dan mengoptimalisasi 4 (empat) buah perangkat NanoStation2 Loco tanpa menggunakan antena tambahan dalam upaya meningkatkan kualitas serta daya jangkau pada suatu sistem jaringan nirkabel (wireless local area network), sehingga dapat memperoleh cakupan yang lebih luas. Perancangan dilakukan di Laboratorium Telekomunikasi Fakultas Teknik Universitas Tanjungpura. Pengujian dilakukan pada seluruh wilayah komplek kampus dengan radius maksimum 250 meter, dengan paramater kekuatan sinyal yang diterima, pingtest, dan kualitas koneksi, serta rugi-rugi lintasan (pathloss) dengan model propagasi Friis. Dari hasil pengujian tanpa halangan atau line of sight (LOS), membuktikan bahwa perangkat access point dapat mencapai jangkauan 250 meter, dan dari hasil pengujian site survey, dapat disimpulkan bahwa lokasi pengamatan dengan kualitas koneksi yang baik hingga sangat baik rata-rata berada dalam radius kurang dari 100 meter dari access point. Sedangkan lokasi pengamatan dengan kualitas koneksi kurang baik rata-rata berada di luar 100 meter dari access point, serta terdapat beberapa lokasi yang tidak dapat melakukan koneksi sama sekali dikarenakan sinyal yang diterima terlalu lemah

    Hybrid Flexible and Rigid Ceramic Insulation

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    A method is provided for closing out the edges of a flexible ceramic insulation member including inner and outer mold line covering layers. A rigid, segmented, ceramic frame is placed round the edges of the insulation member and exposed edges of the inner and outer mold line covering layers are affixed to the ceramic frame. In one embodiment wherein the covering layers comprise fabrics, the outer fabric is bonded to the top surface and to grooved portion of the side surface of the frame. In another embodiment wherein the outer cover layer comprises a metallic foil, clips on the edges of the frame are used to engage foil extensions. The ceramic frame is coated with a high emittance densifier coating

    Flexible Ceramic-Metal Insulation Composite and Method of Making

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    A method for joining a woven flexible ceramic fabric and a thin metal sheet creating an integral metal surfaced flexible thermal protection article, which methods compress: placing multiple dots of high temperature metallic or fabric and the thin metal sheet in a random or organized pattern, with the proviso that the brazing material covers about 10% or less of the surface of one flat side of the metal sheet; heating the flexible ceramic fabric, brazing material and thin metal sheet for a predetermined period of time to integrally connect the same; and cooling the formed flexible article to ambient temperature. Preferably the flexible ceramic is selected from fibers comprising atoms of silicon, carbon, nitrogen, boron, oxygen or combinations thereof. The flexible thermal protection article produced is also part of the present invention. The thin metal sheet is comprised of titanium, aluminum, chromium, niobium or alloys or combinations thereof. The brazing material is selected from copper/silver or copper/gold or is a ceramic brazing or adhesive material

    Secondary polymer layered impregnated tile

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    A low density organic polymer impregnated preformed fibrous ceramic article includes a plurality of layers. A front layer includes ceramic fibers or carbon fibers or combinations of ceramic fibers and carbon fibers, and is impregnated with an effective amount of at least one organic polymer. A middle layer includes polymer impregnated ceramic fibers. A back layer includes ceramic fibers or carbon fibers or combinations of ceramic fibers and carbon fibers, and is impregnated with an effective amount of at least one low temperature pyrolyzing organic polymer capable of decomposing without depositing residues

    Multilayer Impregnated Fibrous Thermal Insulation Tiles

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    The term "secondary polymer layered impregnated tile" ("SPLIT") denotes a type of ablative composite-material thermal- insulation tiles having engineered, spatially non-uniform compositions. The term "secondary" refers to the fact that each tile contains at least two polymer layers wherein endothermic reactions absorb considerable amounts of heat, thereby helping to prevent overheating of an underlying structure. These tiles were invented to afford lighter-weight alternatives to the reusable thermal-insulation materials heretofore variously used or considered for use in protecting the space shuttles and other spacecraft from intense atmospheric-entry heating

    Durable Advanced Flexible Reusable Surface Insulation

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    An improved flexible blanket includes a nickel-based alloy foil layer brazed to a nickel-based alloy fabric layer. The fabric layer is stitched to an underlying ceramic insulation layer

    Working through whiteness, race and (anti) racism in physical education teacher education

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    Background: The persistent gaps between a largely white profession and ethnically diverse school populations have brought renewed calls to support teachers' critical engagement with race. Programmes examining the effects of racism have had limited impact on practice, with student teachers responding with either denial, guilt or fear; they also contribute to a deficit view of racialised students in relation to an accepted white ‘norm’, and position white teachers ‘outside’ of race. Recent calls argue for a shift in focus towards an examination of the workings of the dominant culture through a critical engagement with whiteness, positioning white teachers within the processes of racialisation. Teacher educators' roles are central, and yet, while we routinely expect student teachers to reflect critically on issues of social justice, we have been less willing to engage in such work ourselves. This is particularly the case within physical education teacher education (PETE), an overwhelmingly white, embodied space, and where race and racism as professional issues are largely invisible. Purpose: This paper examines the operation of whiteness within PETE through a critical reflection on the three co-authors' careers and experiences working for social justice. The research questions were twofold: How are race, (anti) racism and whiteness constructed through everyday experiences of families, schooling and teacher education? How can collective biography be used to excavate discourses of race, racism and whiteness as the first step towards challenging them? In beginning the process of reflecting on what it means for us ‘to do own work’ in relation to (anti) racism, we examine some of the tensions and challenges for teacher educators in PE attempting to work to dismantle whiteness. Methodology: As co-authors, we engaged in collective biography work – a process in which we reflected upon, wrote about and shared our embodied experiences and memories about race, racism and whiteness as educators working for social justice. Using a critical whiteness lens, these narratives were examined for what they reveal about the collective practices and discourses about whiteness and (anti)racism within PETE. Results: The narratives reveal the ways in which whiteness operates within PETE through processes of naturalisation, ex-denomination and universalisation. We have been educated, and now work within, teacher education contexts where professional discourse about race at best focuses on understanding the racialised ‘other’, and at worse is invisible. By drawing on a ‘racialised other’, deficit discourse in our pedagogy, and by ignoring race in own research on inequalities in PETE, we have failed to disrupt universalised discourses of ‘white-as-norm’, or addressed our own privileged racialised positioning. Reflecting critically on our biographies and careers has been the first step in recognising how whiteness works in order that we can begin to work to disrupt it. Conclusion: The study highlights some of the challenges of addressing (anti)racism within PETE and argues that a focus on whiteness might offer a productive starting point. White teacher educators must critically examine their own role within these processes if they are to expect student teachers to engage seriously in doing the same

    Value-Driven Analysis of New Paradigms in Space Architectures: An Ilities-Based Approach

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    Current commercial, civil, and military space architecture designs perform exquisitely and reliably. However, today’s architecture paradigms are also characterized by expensive launches, large and expensive high-performance spacecraft, long development cycles, and wide variations in ground architectures. While current assets provide high-quality services, and future assets are slated to improve performance within the same design frameworks, proposed future architectures may not be capitalizing on technology improvements, system innovations, or policy alternatives explored during the last two decades. This paper identifies five “trends” along which space architectures may develop, aimed at granting systems several “ilities,” such as resiliency, robustness, flexibility, scalability, and affordability. The trends examined include: commercialization of space, significant reductions in launch costs and the development of hybrid or reusable launch systems, development of on-orbit infrastructure and servicing, aggregation or disaggregation of orbital assets, and the automation and standardization of ground architectures. Further refinement of these key technological and system trends could result in major paradigm shifts in the development and fielding of space operations as well as lead to space architecture designs in the future that are radically different from those today. Within the framework of systems engineering ilities and risk management, this paper reviews current literature surrounding these new change trends and justifies their potential to cause significant paradigm shifts. By examining the work and research conducted so far through an ilities-based approach, systems engineers can more fully appreciate the value being offered by these trends
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