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1271	Digital Soil Mapping of the Purdue Agronomy Center for Research and Education Shams R Rahmani (8300103) 07 May 2020 (has links) This research work concentrate on developing digital soil maps to support field based plant phenotyping research. We have developed soil organic matter content (OM), cation exchange capacity (CEC), natural soil drainage class, and tile drainage line maps using topographic indices and aerial imagery. Various prediction models (universal kriging, cubist, random forest, C5.0, artificial neural network, and multinomial logistic regression) were used to estimate the soil properties of interest. Agricultural Land Management Agricultural Land Planning Sustainable Agricultural Development Agronomy Digital soil mapping (DSM) Organic matter content Cation exchange capacity Natural soil drainage classes geostatistical methods Cubist modeling Random Forest models Universal Kriging C5.0 or see5 modeling Artificial neural network Tile drainage lines Soil spatial variation Plant Phenotyping Aerial Imagery digital elevation model (DEM) terrain attributes Soil and Landscape Very poorly drained poorly drained somewhat poorly drained moderately well drained User's accuracy producer's accuracy kappa coefficient Multinomial logit regression Tile Probe topographic wetness index Topographic Position Index slope height cross sectional curvature Relative slope position channel network distance SSURGO soils data internal validation external validation
1272	Unapređenje kvaliteta alata za livenje pod pritiskom primenom tehnologija inženjerstva površina / Application of surface engineering technologies for improvement of diecasting tools quality Terek Pal 21 September 2016 (has links) <p>Proučavane su koroziona postojanost i tendencija lepljenja različitih<br />materijala u kontaktu sa tečnom Al–Si–Cu legurom. Ispitivanjem su<br />obuhvaćeni čelik za rad na toplo, plazma nitrirani čelik i dupleks<br />slojevi sa CrN, TiAlN, TiAlSiN i CrAlN prevlakama, različitog nivoa<br />površinske hrapavosti. Za ispitivanja pomenutih fenomena<br />primenjena je metoda izvlačenja, koja je unapređena kako bi se povećale<br />njena tačnost i verodostojnost simulacije procesa livenja. Korozioni<br />efekti su pojačani tako što su uzorci osim kratkog kontakta sa odlivkom<br />zadržavani i u dužim periodima u kontaktu sa tečnom legurom (5 i 20<br />min). Uprkos opštim stavovima, za ispitivane materijale je<br />ustanovljeno da su sile izvlačenja uzoraka iz Al–Si–Cu odlivaka<br />nezavisne od njihovog hemijskog sastava. Uticaj hrapavosti je izražen<br />kod uzoraka sa prevlakama kod kojih pri smanjenju hrapavosti dolazi do<br />povećanja sile izvlačenja. Sve ispitane prevlake su sklone mehaničkom<br />lepljenju Al–Si–Cu legure za svoje površine, ali sa aspekta korozije u<br />tečnom metalu značajno prevazilaze performanse čelika i plazma<br />nitriranog sloja. Duži kontakt livene legure sa površinama prevlaka<br />uzrokovao je niže vrednosti sila izvlačenja, što je posledica<br />oksidacije površina prevlaka. Ustanovljeno je da su ispitivane<br />prevlake inertne ka tečnoj leguri aluminijuma. Međutim, dolazi do<br />oksidacije i korozije materijala podloge kroz greške rasta koje su<br />prisutne u prevlakama. Stečena znanja o identifikovanim<br />mehanizmima habanja i propadanja zaštitnih slojeva prevlaka<br />poslužiće daljem razvoju dupleks slojeva namenjenih za zaštitu alata<br />za livenje pod pritiskom.</p> / <p>Corrosion resistance and soldering tendency of different materials in molten<br />Al–Si–Cu alloy were studied. Hot-working tool steel, plasma nitrided steel and<br />duplex layers with CrN, TiAlN, TiAlSiN and CrAlN top coatings, which were<br />produced to various degree of surface roughness, were covered by the study.<br />An ejection test was employed for investigation of the concerned phenomena.<br />The ejection test was improved in order to increase its accuracy and the<br />reliability of process simulation. Samples were examined in both short and<br />extended periods of contact (5 and 20 min) with liquid casting. Casting<br />solidification was extended in order to intensify the corrosion effects. Contrary<br />to common findings, it was found that the ejection force of the investigated<br />materials does not depend on their chemical composition. For the coated<br />samples, a pronounced dependence of the ejection force on the surface<br />roughness was found. The ejection force increases with decrease in surface<br />roughness. All investigated coatings are prone to mechanical soldering by Al–<br />Si–Cu alloy. Still, their corrosion resistance substantially exceeds the corrosion<br />resistance of steel and plasma nitrided layer. Longer exposure of coated<br />samples to cast alloy induced lower ejection forces, which is a consequence<br />of coatings oxidation. It was found that the investigated coatings are inert to<br />liquid aluminium. However, the underlying material undergoes oxidation and<br />corrosion through coating growth defects. The findings concerning the wear<br />mechanisms of protective layers support further development of duplex layers<br />intended for die casting tools protection.</p>
1273	BBT Acoustic Alternative Top Bracing CADD Data Set-NoRev-2022Jun28 Hemphill, Bill 22 July 2022 (has links) This electronic document file set consists of an overview presentation (PDF-formatted) file and companion video (MP4) and CADD files (DWG & DXF) for laser cutting the ETSU-developed alternate top bracing designs and marking templates for the STEM Guitar Project’s BBT (OM-sized) standard acoustic guitar kit. The three (3) alternative BBT top bracing designs in this release are (a) a one-piece base for the standard kit's (Martin-style) bracing, (b) 277 Ladder-style bracing, and (c) an X-braced fan-style bracing similar to traditional European or so-called 'classical' acoustic guitars. The CADD data set for each of the three (3) top bracing designs includes (a) a nominal 24" x 18" x 3mm (0.118") Baltic birch plywood laser layout of (1) the one-piece base with slots, (2) pre-radiused and pre-scalloped vertical braces with tabs to ensure proper orientation and alignment, and (3) various gages and jigs and (b) a nominal 15" x 20" marking template. The 'provided as is" CADD data is formatted for use on a Universal Laser Systems (ULS) laser cutter digital (CNC) device. Each CADD drawing is also provided in two (2) formats: Autodesk AutoCAD 2007 .DWG and .DXF R12. Users should modify and adapt the CADD data as required to fit their equipment. This CADD data set is released and distributed under a Creative Commons license; users are also encouraged to make changes o the data and share (with attribution) their designs with the worldwide acoustic guitar building community. BBT acoustic guitar brace bracing top CADD CAD DWG DXF R12 lutier ETSU OM orchestra model STEM STEM Guitar building project kit storefront 3mm 0.118" Baltic birch plywood sheet 24 18 3mm 0.118 laser cut engrave etch marking template layout Martin Martin-style X-brace X-bracing X-braced X tone arm tonal variant alternative alt ladder 277 fan classicial European tab slot bump out radiused 300 inch 25 foot 762 meter radius base vertical scallop glue wood go-bar go bar deck jig fixture gage gauge headstock head plate neck contour fret stack stackable align alignment position orientation vertical perpendicular T1 upper bout lower kerfing sand chisel shape weight lighten light tone tap carbon-dioxide CO2 10.6 µm Universal Laser Systems ULS workboard waxed baker sheet Acoustics, Dynamics, and Controls Adult and Continuing Education Algebraic Geometry Appalachian Studies Art Education Educational Technology Elementary Education and Teaching Engineering Education Geometry and Topology Harmonic Analysis and Representation Higher Education and Teaching Industrial and Product Design Manufacturing Music Music Education Other Engineering Science and Materials Polymer and Organic Materials Science and Mathematics Education Secondary Education and Teaching Structural Materials Vocational Education
1274	BBT Acoustic Alternative Top Bracing CADD Data Set-NoRev-2022Jun28 Hemphill, Bill 22 July 2022 (has links) This electronic document file set consists of an overview presentation (PDF-formatted) file and companion video (MP4) and CADD files (DWG & DXF) for laser cutting the ETSU-developed alternate top bracing designs and marking templates for the STEM Guitar Project’s BBT (OM-sized) standard acoustic guitar kit. The three (3) alternative BBT top bracing designs in this release are (a) a one-piece base for the standard kit's (Martin-style) bracing, (b) 277 Ladder-style bracing, and (c) an X-braced fan-style bracing similar to traditional European or so-called 'classical' acoustic guitars. The CADD data set for each of the three (3) top bracing designs includes (a) a nominal 24" x 18" x 3mm (0.118") Baltic birch plywood laser layout of (1) the one-piece base with slots, (2) pre-radiused and pre-scalloped vertical braces with tabs to ensure proper orientation and alignment, and (3) various gages and jigs and (b) a nominal 15" x 20" marking template. The 'provided as is" CADD data is formatted for use on a Universal Laser Systems (ULS) laser cutter digital (CNC) device. Each CADD drawing is also provided in two (2) formats: Autodesk AutoCAD 2007 .DWG and .DXF R12. Users should modify and adapt the CADD data as required to fit their equipment. This CADD data set is released and distributed under a Creative Commons license; users are also encouraged to make changes o the data and share (with attribution) their designs with the worldwide acoustic guitar building community. BBT acoustic guitar brace bracing top CADD CAD DWG DXF R12 lutier ETSU OM orchestra model STEM STEM Guitar building project kit storefront 3mm 0.118" Baltic birch plywood sheet 24 18 3mm 0.118 laser cut engrave etch marking template layout Martin Martin-style X-brace X-bracing X-braced X tone arm tonal variant alternative alt ladder 277 fan classicial European tab slot bump out radiused 300 inch 25 foot 762 meter radius base vertical scallop glue wood go-bar go bar deck jig fixture gage gauge headstock head plate neck contour fret stack stackable align alignment position orientation vertical perpendicular T1 upper bout lower kerfing sand chisel shape weight lighten light tone tap carbon-dioxide CO2 10.6 µm Universal Laser Systems ULS workboard waxed baker sheet Acoustics, Dynamics, and Controls Adult and Continuing Education Algebra Algebraic Geometry Appalachian Studies Applied Mathematics Art Education Biology Computer-Aided Engineering and Design Educational Technology Elementary Education and Teaching Engineering Education Engineering Science and Materials Forest Sciences Geometry and Topology Harmonic Analysis and Representation Industrial and Product Design Manufacturing Music Music Education Other Engineering Other Engineering Science and Materials Physics Polymer and Organic Materials Polymer Chemistry Science and Mathematics Education Secondary Education and Teaching Structural Materials Vocational Education

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