76 research outputs found

    RANCANG BANGUN SISTEM KONTROL PADA KOMPRESOR TEKANAN UDARA SEBAGAI PENGISI UDARA UNTUK BAN KENDARAAN

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    Perkembangan teknologi membuat masyarakat membutuhkan alat yang beroperasi secara otomatis dan efisien. Oleh karena itu penulis memanfaatkan fungsi dari inverter satu fase untuk mengontrol kecepatan putaran motor. Tujuan proyek akhir ini antara lain membuat sistem kontrol pada kompresor yang siap digunakan setiap waktu, membuat hardware dan software sistem kontrol pada kompresor tekanan udara sebagai pengisi udara ban kendaraan serta membuat sistem kontrol pada kompresor tekanan udara sebagai pengisi udara pada kendaraan sehingga menjadi lebih efisien. Metode yang dipakai yaitu inverter single phase full bridge inverter dengan menggunakan metode switching SPWM (Sinusoidal Pulse Width Modulation). Input tegangan inverter berasal dari rectifier (tegangan jala-jala yang disearahkan). Frekuensi tegangan output inverter dapat diatur ( variabel) melalui program dari mikrokontroler berdasarkan pembacaan sensor. Pulsa keluaran dari mikrokontroler sebagai drive IGBT tidak langsung dihubungkan dengan IGBT tetapi melalui rangkaian optocoupler. Rangkaian tersebut berfungsi sebagai rangkaian pemisah elektrik antara tegangan rendah dengan tegangan tinggi. Sistem kontrol pada kompresor yang dibuat belum dapat mengontrol kecepatan motor pada kompresor. Dikarenakan inverter yang telah dibuat memiliki gelombang tegangan output yang tidak sinusoida, maka hanya mampu untuk beban linier yaitu lampu pijar 60 Watt, 100 Watt dan beban motor 125 watt. Proses pengisian tekanan ban kendaraan menjadi lebih efisien disebabkan pada saat proses pengisian tekanan ban kendaraan hanya dilakukan satu kali dan tidak membutuhkan ulangan. Apabila setting tekanan 30 psi maka tekanan pada ban adalah 31, 5 psi. Diperoleh selisih tekanan setting point dengan tekanan pada ban adalah 1,5 ps

    Monazite trumps zircon: applying SHRIMP U–Pb geochronology to systematically evaluate emplacement ages of leucocratic, low-temperature granites in a complex Precambrian orogen

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    Although zircon is the most widely used geochronometer to determine the crystallisation ages of granites, it can be unreliable for low-temperature melts because they may not crystallise new zircon. For leucocratic granites U–Pb zircon dates, therefore, may reflect the ages of the source rocks rather than the igneous crystallisation age. In the Proterozoic Capricorn Orogen of Western Australia, leucocratic granites are associated with several pulses of intracontinental magmatism spanning ~800 million years. In several instances, SHRIMP U–Pb zircon dating of these leucocratic granites either yielded ages that were inconclusive (e.g., multiple concordant ages) or incompatible with other geochronological data. To overcome this we used SHRIMP U–Th–Pb monazite geochronology to obtain igneous crystallisation ages that are consistent with the geological and geochronological framework of the orogen. The U–Th–Pb monazite geochronology has resolved the time interval over which two granitic supersuites were emplaced; a Paleoproterozoic supersuite thought to span ~80 million years was emplaced in less than half that time (1688–1659 Ma) and a small Meso- to Neoproterozoic supersuite considered to have been intruded over ~70 million years was instead assembled over ~130 million years and outlasted associated regional metamorphism by ~100 million years. Both findings have consequences for the duration of associated orogenic events and any estimates for magma generation rates. The monazite geochronology has contributed to a more reliable tectonic history for a complex, long-lived orogen. Our results emphasise the benefit of monazite as a geochronometer for leucocratic granites derived by low-temperature crustal melting and are relevant to other orogens worldwide

    Modified carbon-containing electrodes in stripping voltammetry of metals

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    Adenovirus Gene Transfer to Amelogenesis Imperfecta Ameloblast-Like Cells

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    To explore gene therapy strategies for amelogenesis imperfecta (AI), a human ameloblast-like cell population was established from third molars of an AI-affected patient. These cells were characterized by expression of cytokeratin 14, major enamel proteins and alkaline phosphatase staining. Suboptimal transduction of the ameloblast-like cells by an adenovirus type 5 (Ad5) vector was consistent with lower levels of the coxsackie-and-adenovirus receptor (CAR) on those cells relative to CAR-positive A549 cells. To overcome CAR -deficiency, we evaluated capsid-modified Ad5 vectors with various genetic capsid modifications including “pK7” and/or “RGD” motif-containing short peptides incorporated in the capsid protein fiber as well as fiber chimera with the Ad serotype 3 (Ad3) fiber “knob” domain. All fiber modifications provided an augmented transduction of AI-ameloblasts, revealed following vector dose normalization in A549 cells with a superior effect (up to 404-fold) of pK7/RGD double modification. This robust infectivity enhancement occurred through vector binding to both αvβ3/αvβ5 integrins and heparan sulfate proteoglycans (HSPGs) highly expressed by AI-ameloblasts as revealed by gene transfer blocking experiments. This work thus not only pioneers establishment of human AI ameloblast-like cell population as a model for in vitro studies but also reveals an optimal infectivity-enhancement strategy for a potential Ad5 vector-mediated gene therapy for AI

    Gut mucosal DAMPs in IBD: From mechanisms to therapeutic implications

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    Endogenous damage-associated molecular patterns (DAMPs) are released during tissue damage and have increasingly recognized roles in the etiology of many human diseases. The inflammatory bowel diseases (IBD), ulcerative colitis (UC) and Crohn’s disease (CD), are immune-mediated conditions where high levels of DAMPs are observed. DAMPs such as calprotectin (S100A8/9) have an established clinical role as a biomarker in IBD. In this review, we use IBD as an archetypal common chronic inflammatory disease to focus on the conceptual and evidential importance of DAMPs in pathogenesis and why DAMPs represent an entirely new class of targets for clinical translation. </p

    miRNAs as Biomarkers and Therapeutic Targets in Non-Small Cell Lung Cancer: Current Perspectives

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    An Adaptive Monitoring Scheme for Automatic Control of Anaesthesia in dynamic surgical environments based on Bispectral Index and Blood Pressure.

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    During surgical procedures, bispectral index (BIS) is a well-known measure used to determine the patient's depth of anesthesia (DOA). However, BIS readings can be subject to interference from many factors during surgery, and other parameters such as blood pressure (BP) and heart rate (HR) can provide more stable indicators. However, anesthesiologist still consider BIS as a primary measure to determine if the patient is correctly anaesthetized while relaying on the other physiological parameters to monitor and ensure the patient's status is maintained. The automatic control of administering anesthesia using intelligent control systems has been the subject of recent research in order to alleviate the burden on the anesthetist to manually adjust drug dosage in response physiological changes for sustaining DOA. A system proposed for the automatic control of anesthesia based on type-2 Self Organizing Fuzzy Logic Controllers (T2-SOFLCs) has been shown to be effective in the control of DOA under simulated scenarios while contending with uncertainties due to signal noise and dynamic changes in pharmacodynamics (PD) and pharmacokinetic (PK) effects of the drug on the body. This study considers both BIS and BP as part of an adaptive automatic control scheme, which can adjust to the monitoring of either parameter in response to changes in the availability and reliability of BIS signals during surgery. The simulation of different control schemes using BIS data obtained during real surgical procedures to emulate noise and interference factors have been conducted. The use of either or both combined parameters for controlling the delivery Propofol to maintain safe target set points for DOA are evaluated. The results show that combing BIS and BP based on the proposed adaptive control scheme can ensure the target set points and the correct amount of drug in the body is maintained even with the intermittent loss of BIS signal that could otherwise disrupt an automated control system
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