PROSES PEMBUATAN CASING PADA MESIN PEMERAS KELAPA PARUT

Tujuan dari proyek akhir ini adalah untuk mengetahui cara pembuatan mesin pemeras kelapa parut, khususnya dalam pembuatan casing, yaitu metode yang digunakan dengan mengidentifikasi gambar kerja. Dari identifikasi gambar kerja, diperoleh gambaran tentang konstruksi yang akan dibuat. Proses pembuatan casing pemeras kelapa parut meliputi : Melukis bahan, pengurangan volume bahan, perakitan bahan, dan penyempurnaan permukaan. Sedangkan casing yang dibuat dapat dilakukan dengan cara / langkah-langkah sebagai berikut : Membaca gambar kerja, pengukuran, pelukisan, pemotongan, penekukan, pengeboran, perakitan, penyempurnaan permukaan dan finishing.; Sedangkan peralatan yang digunakan dalam proses pembuatan casing terdiri dari : penggores (spidol), mistar baja, mistar siku (penyiku), roll meter, mesin potong (guillotine), gunting tangan, palu, penitik, mesin bor, kikir, tang rivet, kompresor udara dan spray gun.; dan peralatan yang digunakan untuk keselamatan kerja meliputi : wear pack, kaca mata, sepatu safety, sarung tangan dan penutup telinga. Casing yang dibuat menggunakan bahan plat eysser dengan ketebalan 0,8 mm. Ukuran masing-masing casing yang di buat antara lain, yaitu: casing atas ( tutup box ) dengan ukuran 370 x 350 x 0,8 mm dan casing atas bagian dalam (stainlles steel) dengan ukuran 370 x 350 x 0,8 mm, casing bagian depan, sisi kanan dan bagian sisi kiri dengan ukuran 750 x 350 x 0,8 mm, sedangkan casing belakang bagian atas dengan ukuran 585 x 350 x 0,8 mm dan casing belakang bagian bawah tutup mesin dengan ukuran 330 x 160 x 0,8 mm. Setelah dilakukan uji kinerja di dapatkan hasil bahwa mesin pemeras kelapa parut dapat memproduksi santan sebanyak ± 6 liter/20 menit

A kinematic and computational study of leech crawling: Support for a CPG based on travelling waves of excitation.

Many well characterized central pattern generators (CPGs) underlie behaviors (e.g., swimming, flight, heartbeat) that require regular rhythmicity and strict phase relationships. Here, we examine the organization of a CPG for leech crawling, a behavior whose success depends more on its flexibility than on its precise coordination. We examined the organization of this CPG by first characterizing the kinematics of crawling steps in normal and surgically manipulated animals, then by exploring its features in a simple neuronal model. The behavioral observations revealed the following. (1) Intersegmental coordination varied considerably with step duration, whereas the rates of elongation and contraction within individual segments were relatively constant. (2) Steps were generated in the absence of both head and tail brains, implying that midbody ganglia contain a CPG for step production. (3) Removal of sensory feedback did not affect step coordination or timing. (4) Imposed stretch greatly lengthened transitions between elongation and contraction, indicating that sensory pathways feed back onto the CPG. A simple model reproduced essential features of the observed kinematics. This model consisted of an oscillator that initiates propagating segmental waves of activity in excitatory neuronal chains, along with a parallel descending projection; together, these pathways could produce the observed intersegmental lags, coordination between phases, and step duration. We suggest that the proposed model is well suited to be modified on a step-by-step basis and that crawling may differ substantially from other described CPGs, such as that for swimming in segmented animals, where individual segments produce oscillations that are strongly phase-locked to one another

Mechanics of blood flow in capillaries

This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.Blood is a concentrated suspension of red blood cells (RBCs). Motion and deformation of RBCs can be analyzed based on knowledge of their mechanical characteristics. Models for single-file motion of RBCs in capillaries yield predictions of apparent viscosity in good agreement with experimental results for diameters up to about 8 μm. In living microvessels, flow resistance is also strongly influenced by the presence of a ~ 1-micron layer of macromolecules bound to the inner lining of vessel walls, the endothelial surface layer. Two-dimensional simulations, in which each RBC is represented as a set of interconnected viscoelastic elements, predict that off-center RBCs take asymmetric shapes and drift toward the center-line. Predicted trajectories agree closely with observations in microvessels of the rat mesentery. Realistic simulation of multiple interacting RBCs in microvessels remains as a major challenge for future work.This work was supported by NIH Grant HL034555

A perspective on specifying and verifying concurrent modules

The specification of a concurrent program module, and the verification of implementations and clients with respect to such a specification, are difficult problems. A specification should be general enough that any reasonable implementation satisfies it, yet precise enough that it can be used by any reasonable client. We survey a range of techniques for specifying concurrent modules, using the example of a counter module to illustrate the benefits and limitations of each. In particular, we highlight four key concepts underpinning these techniques: auxiliary state, interference abstraction, resource ownership and atomicity. We demonstrate how these concepts can be combined to achieve two powerful approaches for specifying concurrent modules and verifying implementations and clients, which remove the limitations highlighted by the counter example

Nonmethane hydrocarbon and halocarbon distributions during Atlantic Stratocumulus Transition Experiment/Marine Aerosol and Gas Exchange, June 1992

Aircraft measurements of selected nonmethane hydrocarbon and halocarbon species were made in the lower troposphere of the NE Atlantic near the Azores, Portugal, during June 1992 as part of the Atlantic Stratocumulus Transition Experiment/Marine Aerosol and Gas Exchange. In this paper, the impact of continental outflow from both Europe and North America on the study region were assessed. Four main air mass types were characterized from trajectories and trace gas concentrations: clean marine from the Atlantic, and continental air from the Iberian Peninsula, the British Isles and Northern Europe, and North America. Each classification exhibited trace gas concentrations that had been modified en route by photochemical processes and mixing. Comparison with the clean marine boundary layer (MBL) shows that the boundary layer of the predominantly continental air masses were enhanced in hydrocarbons and halocarbons by factors of approximately 2 for ethane, 5 for propane, 2-6 for ethyne and benzene, and 2-3 for C2Cl4. The same air masses also exhibited large ozone enhancements, with 2 to 3 times higher mixing ratios in the continental boundary layer air compared to the clean MBL. This indicates a primarily anthropogenic photochemical source for a significant fraction of the lower tropospheric ozone in this region. Methyl bromide exhibited on average 10-20% higher concentrations in the boundary layer affected by continental outflow than in the clean MBL, and was seen to be enhanced in individual plumes of air of continental origin. This is consistent with significant anthropogenic sources for methyl bromide. In addition, median MBL concentrations of ethene and methyl iodide showed enhancements of approximately a factor of 2 above free tropospheric values, suggesting primarily coastal/oceanic sources for these species. Copyright 1996 by the American Geophysical Union

Self similar sets, entropy and additive combinatorics

This article is an exposition of recent results on self-similar sets, asserting that if the dimension is smaller than the trivial upper bound then there are almost overlaps between cylinders. We give a heuristic derivation of the theorem using elementary arguments about covering numbers. We also give a short introduction to additive combinatorics, focusing on inverse theorems, which play a pivotal role in the proof. Our elementary approach avoids many of the technicalities in the original proof but also falls short of a complete proof. In the last section we discuss how the heuristic argument is turned into a rigorous one.Comment: 21 pages, 2 figures; submitted to Proceedings of AFRT 2012. v5: more typos correcte

Anomaly Cancelation in Field Theory and F-theory on a Circle

We study the manifestation of local gauge anomalies of four- and six-dimensional field theories in the lower-dimensional Kaluza-Klein theory obtained after circle compactification. We identify a convenient set of transformations acting on the whole tower of massless and massive states and investigate their action on the low-energy effective theories in the Coulomb branch. The maps employ higher-dimensional large gauge transformations and precisely yield the anomaly cancelation conditions when acting on the one-loop induced Chern-Simons terms in the three- and five-dimensional effective theory. The arising symmetries are argued to play a key role in the study of the M-theory to F-theory limit on Calabi-Yau manifolds. For example, using the fact that all fully resolved F-theory geometries inducing multiple Abelian gauge groups or non-Abelian groups admit a certain set of symmetries, we are able to generally show the cancelation of pure Abelian or pure non-Abelian anomalies in these models.Comment: 48 pages, 2 figures; v2: typos corrected, comments on circle fluxes adde