ANALISIS REPAIR POLICY DAN PREVENTIVE MAINTENANCE POLICY UNTUK MENGETAHUI BIAYA YANG OPTIMAL PADA MESIN MV-40 LINE CYLINDER HEAD PT. KUBOTA INDONESIA

PT. Kubota Indonesia merupakan perusahaan yang memproduksi mesin diesel horizontal dengan kapasitas mesin 6.5 – 11 HP. Berdasarkan laporan tahunan bagian produksi, diperoleh data bahwa salah satu mesin, yaitu mesin MV-40 yang terletak pada line cylinder head sering sekali mengalami breakdown sehingga mengganggu proses produksi dan menurunkan produktivitas perusahaan. Dengan menggunakan data breakdown, dan data kerusakan untuk setiap kali terjadi breakdown, analisis dilakukan untuk mengetahui maintenance policy yang harus dilakukan dan jadwal maintenance yang mengoptimalkan biaya-biaya yang terkait dengan aktivitas maintenance. Diagram Pareto dan Diagram Tulang Ikan dipergunakan untuk menganalisis penyebab terjadinya kerusakan mesin MV-40. Dari analisis yang telah dilakukan, diperoleh kesimpulan bahwa frekuensi breakdown Mesin MV-40 mengikuti breakdown case 2, sehingga kebijakan maintenance yang terbaik adalah repair. Kebijakan repair mempunyai rata-rata runtime mesin/periode dan biaya perbaikan yang lebih kecil jika dibandingkan dengan kebijakan preventive maintenance, yaitu 6,78571 bulan dan Rp. 1.132.320,00 per periode. Kata Kunci:maintenance policy, repair policy, preventive maintenance policy, fishbone diagram, pareto diagra

Sistem Informasi dan Pengolahan Data Kriminal di Polres Pasaman Barat dengan Akses Virtual Host Bebasis Client Server Menggunakan Bahasa Pemrograman Php dan Database Mysql

The rapid development of computer technology and information greatly helps work in storing, accessing to data processing becomes faster and easier, this has triggered various fields in utilizing this with the use of computer-based information systems, especially for intelligence units in western security police. The system that will be created uses access to the virtual host-based client server. Modeling used UML modeling, this system is built using PHP programming language and MYSQL database. The results of the study show that the information system designed can process criminal data and is able to be implemented at the research site.

Synthesis of Acrolein From Glycerol Using FePO4 Catalyst in Liquid Phase Dehydration

Acrolein is currently produced using propylene from crude oil while its price and scarcity are increasing. A renewable material such as glycerol is an attractive alternative for acrolein production. It can be obtained from crude palm oil (CPO) and is a byproduct of biodiesel production. Besides being able to compete economically, glycerol is an environmentally friendly material. The purpose of this study is to synthesize acrolein from glycerol using FePO4 catalyst in liquid phase dehydration. The catalyst was prepared by three different methods: hydrothermal (catalyst A), deposition at Fe/P = 1.15 (catalyst B), and deposition at Fe/P = 1.20 (catalyst C). The experimental reaction temperature was varied at 220, 240 and 260 °C under constant atmospheric pressure. The results showed that catalyst C provided the best yield (91%), followed by catalyst A (90%) and catalyst B (82%). The increasing reaction temperature showed a tendency to increase the yield of acrolein, while the presence of oxygen reduced the yield of acrolein and allowed the reaction to produce more side products such as glycerol propanal, acetaldehyde, and propionate. Catalyst reuse without any regeneration resulted in a yield profile of acrolein that continued to decline

Genetic structure and affinities among tribal populations of southern India: a study of 24 autosomal DNA markers

We describe the genetic structure and affinities of five Dravidian-speaking tribal populations inhabiting the Nilgiri hills of Tamil Nadu, in south India, using 24 autosomal DNA markers. Our goals were: (i) to examine what evolutionary forces have most significantly impacted south Indian tribal genetic variation, and (ii) to test whether the phenotypic similarities of some south Indian tribal groups to Africans represent a signature of close relationship to Africans or are due to convergence. All loci were polymorphic and average heterozygosities were substantial (range: 0.347-0.423). Genetic differentiation was high (Gst= 6.7%) and genetic distances were not significantly correlated with geographic distances. Genetic drift therefore probably played a significant role in shaping the patterns of genetic variation observed in southern Indian tribal populations. Otherwise, analyses of population relationships showed that Indian populations are closely related to one another, regardless of phenotypic characteristics, and do not show particular affinities to Africans. We conclude that the phenotypic similarities of some Indian groups to Africans do not reflect a close relationship between these groups, but are better explained by convergence

Soret and Dufour Effects on Transient Double Diffusive Free Convection of Couple-stress Fluid past a Vertical Cylinder

This study examines the influence of Soret and Dufour effects on double diffusive transient free convective boundary layer flow of a couple-stress fluid flowing over a semi-infinite vertical cylinder. A set of non-dimensional governing equations namely, the continuity, momentum, energy and concentration equations is derived and these equations are unsteady non-linear and coupled. As there is no analytical or direct numerical method available to solve these equations, they are solved by using the CFD techniques. An unconditionally stable Crank-Nicolson type of implicit finite difference scheme is employed to obtain the discretized forms of governing equations. These equations are solved using the Thomas and pentadiagonal algorithms. The numerical results are compared and found to be in good agreement with previously published results as special cases of the present investigation. Transient velocity, temperature and concentration profiles, average skin-friction, Nusselt number and Sherwood number are shown graphically for different values of Soret (So) and Dufour (Du) numbers. In all these profiles it is observed that, as the values of So decreases or the Du increases, the time required to reach the temporal maximum and the steady-state increases. It is also observed that the average values of skin-friction and heat transfer rate increases with the increasing values of So or decreasing values of Du. Whereas the reverse trend is observed for the average mass transfer rate

MHD-Conjugate Heat Transfer Analysis for Transient Free Convective Flow Past a Vertical Slender Hollow Cylinder

Abstract In this paper the effects of magnetic field and conduction on the transient free convective boundary layer flow over a vertical slender hollow circular cylinder with the inner surface at a constant temperature are investigated. The transformed dimensionless governing equations for the flow and conjugate heat transfer are solved by using the implicit finite difference scheme. For the validation of the current numerical method heat transfer results for a Newtonian fluid case where the magnetic effect and conduction is zero are compared with those available in the existing literature, and an excellent agreement is obtained. Numerical results for the transient flow variables, average wall shear stress and average heat transfer rate are shown graphically. In all these profiles it is observed that the times needed to reach the steady-state and the temporal maximum increases as the magnetic parameter or conjugate heat transfer parameter increases

Extremely large anthropogenic-aerosol contribution to total aerosol load over the Bay of Bengal during winter season

Ship-borne observations of spectral aerosol optical depth (AOD) have been carried out over the entire Bay of Bengal (BoB) as part of the W-ICARB cruise campaign during the period 27 December 2008–30 January 2009. The results reveal a pronounced temporal and spatial variability in the optical characteristics of aerosols mainly due to anthropogenic emissions and their dispersion controlled by local meteorology. The highest aerosol amount, with mean AOD<sub>500</sub>>0.4, being even above 1.0 on specific days, is found close to the coastal regions in the western and northern parts of BoB. In these regions the Ångström exponent is also found to be high (~1.2–1.25) indicating transport of strong anthropogenic emissions from continental regions, while very high AOD<sub>500</sub> (0.39±0.07) and α<sub>380–870</sub> values (1.27±0.09) are found over the eastern BoB. Except from the large α<sub>380–870</sub> values, an indication of strong fine-mode dominance is also observed from the AOD curvature, which is negative in the vast majority of the cases, suggesting dominance of an anthropogenic-pollution aerosol type. On the other hand, clean maritime conditions are rather rare over the region, while the aerosol types are further examined through a classification scheme based on the relationship between α and <i>d</i>α. It was found that even for the same α values the fine-mode dominance is larger for higher AODs showing the strong continental influence over the marine environment of BoB. Furthermore, there is also an evidence of aerosol-size growth under more turbid conditions indicative of coagulation and/or humidification over specific BoB regions. The results obtained using OPAC model show significant fraction of soot aerosols (~6 %–8 %) over the eastern and northwestern BoB, while coarse-mode sea salt particles are found to dominate in the southern parts of BoB

Neural correlates of hyperalgesia in the monosodium iodoacetate model of osteoarthritis pain

Background: The mechanisms driving osteoarthritic pain remain poorly understood, but there is increasing evidence for a role of the central nervous system in the chronification of pain.We used functional magnetic resonance imaging to investigate the influence of a model of unilateral knee osteoarthritis on nociceptive processing. Results: Four to five weeks post intra-articular injection of monosodium iodoacetate (MIA, 1 mg) into the left knee, Sprague Dawley rats were anesthetized for functional magnetic resonance imaging studies to characterize the neural response to a noxious stimulus (intra-articular capsaicin injection). In a two-arm cross-over design, 5 mM/50 ml capsaicin was injected into either the left knee (n¼8, CAPS-MIA) or right control knee (n¼8, CAPS-CON), preceded by contralateral vehicle (SAL) injection. To assess neural correlates of mechanical hyperalgesia, hindpaws were stimulated with von Frey hairs (8 g: MIA; 15 g: control knee, based on behavioral withdrawal responses). The CAPS-MIA group exhibited significant activation of the periaqueductal gray, unilateral thalamus and bilateral mensencephalon, superior-colliculus, and hippocampus, with no significant activation in the other groups/conditions. Capsaicin injection increased functional connectivity in the mid-brain network and mediodorsal thalamic nucleus, hippocampus, and globus pallidus, which was significantly stronger in CAPS-MIA compared to CAPS-CON groups. Mechanical stimulation of the hyperalgesic (ipsilateral to MIA knee) and normalgesic (contralateral) hindpaws evoked qualitatively different brain activation with more widespread brainstem and anterior cingulate (ACC) activation when stimulating the hyperalgesic paw, and clearer frontal sensory activation from the normalgesic paw. Conclusions: We provide evidence for modulation of nociceptive processing in a chronic knee osteoarthritis pain model with stronger brain activation and alteration of brain networks induced by the pro-nociceptive stimulus. We also report a shift to a medial pain activation pattern following stimulation of the hyperalgesic hindpaw. Taken together, our data support altered neural pain processing as a result of peripheral and central pain sensitization in this model