Mean flow field and surface heating produced by unequal shock interactions at hypersonic speeds

Mean velocity profiles were measured in a free shear layer produced by the interaction of two unequal strength shock waves at hypersonic free-stream Mach numbers. Measurements were made over a unit Reynolds number range of 3,770,000 per meter to 17,400,000 per meter based on the flow on the high velocity side of the shear layer. The variation in measured spreading parameters with Mach number for the fully developed flows is consistent with the trend of the available zero velocity ratio data when the Mach numbers for the data given in this study are taken to be characteristic Mach numbers based on the velocity difference across the mixing layer. Surface measurements in the shear-layer attachment region of the blunt-body model indicate peak local heating and static pressure consistent with other published data. Transition Reynolds numbers were found to be significantly lower than those found in previous data

Thermal and mechanical development of extremely high heat flux cooling modules based on jet array technology

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1997.Includes bibliographical references.by Rudy S. Dahbura.M.S

Analisis dan Perancangan Aplikasi Berbasis Web E-Procurement di PT Pillar Utama Contrindo

The aim of this research is to analyze the current business process at the procurement department at PT Pillar Utama Contrindo as well as develop a web based e-procurement application prototype to supportprocurement process at the company. Interview, survey, as well as analysis and design to develop the prototype are used in the research. The research results in an e-procurement application prototype built to minimize errors on related document filling, help the company to get best price on their supply, and increase control. It can be concluded from the research that the protoype can be implemented to be a tool for the users to decide the best supplier, obtain the best price, and increase control in buying process at PT Pillar Utama Contrindo

Optimalisasi Sistem Perawatan Dan Perbaikan Terencana Mesin Produksi Berdasarkan Analisis Keandalan Pada Pltd Hatiwe Kecil Kota Ambon

Based on preliminary surveys, PLTD X has been operated long enough so that the generator engines often impaired even cause damages during operation. Even maintenance system contained in the PLTD X also has not done, which means there decrease in the production of electrical power generated.Maintenance activities that have been performed by PLTD X is the replacement of engine components damaged as a rejuvenation effort and overhaul that aims to extend the lifespan of the machine, but it is also the act of Preventive maintenance which aims to treat the machines that do not damage or interruption in operation. The dispute resolution process is the method for analyzing the Reliability Centered Maintenance component failure with FBD, System function and functional failure, FMEA and RCM Decision Worksheet. It also can determine the value of Mean Time To Failure (MTTF) and Mean Time To Repair (MTTR) is used to analyze systems engine maintenance. and as a basis for determining the time interval maintenance and total cost of maintenance.Based on the results of the calculation known critical components such as Cylinder Head, Inlet valve, Gasket, Exhaust Valve Housing, Exhaust Valve. Component maintenance time intervals determined by the RCM method is as follows, Cylinder Head with interval 4458 hours, Inlet Valve with 1601 hour, Gasket with 4682 Hours, Exhaust Valve Housing with 1908 hours, Exhaust Valve with 2238 hour. Critical component consisting of Cylinder Head, Inlet Valve, Gasket, Exhaust Vave Housing and Exhaust Valve is usingSchedulled Restoration Task type of maintenance

Efektivitas Penggunaan Arang Kayu dan Batok Kelapa sebagai Penghambat Kerusakan Fisik dan Kimia pada Dedak pada Selama Proses Penyimpanan 8 Minggu

Rice bran is a side product of the rice mill in producing rice. Rice bran is the part of rice husk thatis generated from the rice bleaching process. This feed is a material that would become fragile oreasily damage if it is kept beyond a certain time. The oil content that is relatively high makes ricebran not durable because oil is easily hydrolyzed so that make it rancid due lipase contained inrice. Prevention of feed damage during storage can be done by providing materials containingcertain active substances that can prevent damage. Charcoal gives a solution to prevent damageduring storage because of feed ingredients are hygroscopic and porous, which can absorb water upto the point of balance. The purpose of this study was to determine the effect of the use of woodcharcoal and coconut shell charcoal to physical and chemical damage of rice bran during 8 weeksperiod of storage. The experimental method that was used in this study is completely randomizeddesign CRD with 3 treatments and 4 replications. The use of coconut shell charcoal is better inmaintaining the rice bran odor, reducing the decrease of fat levels and minimizing the increase ofperoxide when compared to administration of charcoal wood

Structural changes in intestinal enteroendocrine cells after ileal interposition in normal rats

INTRODUCTION: No therapeutic approach has significantly impacted the progression of diabetes. As early improvement of glicaemic control is observed after bariatric surgeries, there is currently a search for surgical procedures that can promote euglycemia also in non-obese patients. Glicaemic control can be achieved by increasing the blood concentration of GLP-1, a hormone produced by L cells that are more densely concentrated in the terminal ileum. The interposition of ileal segment to a more anterior region (proximal jejunum) can promote a greater stimulation of the L cells by poorly digested food, increasing the production of GLP-1 and reflecting on glicaemic control.
AIMS: To investigate long-term histological modifications of intestinal mucosa of rats submitted to interposition of ileum segment to a proximal region (jejunum).
METHODS: Forty 8-week old male Wistar-EPM1 rats (Rattus norvegicus albinus) were randomly distributed into 3 groups: the Interposition Group (IG) was subjected to ileal interposition, the Sham Group (SG) was subjected to sham operations, and the Control Group (CG) was not subjected to surgery. All animals were followed until the 60th postoperative day (8 postoperative week) when they were euthanized. Segments of jejunum and ileum from all groups were collected and analyzed by optical microscopy and immunohistochemistry.
RESULTS: No structural nor histological changes in intestinal L cells in the interposed intestinal segment and other intestinal segments were noted after ileal interposition surgery. 
CONCLUSION: As L cells endocrine characteristics were likely maintained, the use of metabolic surgical techniques for the treatment of metabolic diseases, especially diabetes, seems to be justified

A Chandra observation of the long-duration X-ray transient KS 1731-260 in quiescence: too cold a neutron star?

After more than a decade of actively accreting at about a tenth of the Eddington critical mass accretion rate, the neutron-star X-ray transient KS 1731-260 returned to quiescence in early 2001. We present a Chandra/ACIS-S observation taken several months after this transition. We detected the source at an unabsorbed flux of ~2 x 10^{-13} erg/cm^2/s (0.5-10 keV). For a distance of 7 kpc, this results in a 0.5-10 keV luminosity of ~1 x 10^{33} erg/s and a bolometric luminosity approximately twice that. This quiescent luminosity is very similar to that of the other quiescent neutron star systems. However, if this luminosity is due to the cooling of the neutron star, this low luminosity may indicate that the source spends at least several hundreds of years in quiescence in between outbursts for the neutron star to cool. If true, then it might be the first such X-ray transient to be identified and a class of hundreds of similar systems may be present in the Galaxy. Alternatively, enhanced neutrino cooling could occur in the core of the neutron star which would cool the star more rapidly. However, in that case the neutron star in KS 1731-260 would be more massive than those in the prototypical neutron star transients (e.g., Aql X-1 or 4U 1608-52).Comment: Accepted for publicaton in ApJ letters, 13 September 200