The study to evaluate the toxicity of used drilling muds (drilling wastes) and their impact on gill structure of the post larvae of tiger prawn Penaeus monodon has been done. The results showed that the 96 h LC50 of used drilling muds ranged from 30740 and 78271 ppm SPP. All toxicity values considered to be above the standard of Indonesian government (LC50≤30000 ppm SPP). Histological observati...

OBJECTIVES The purpose of this study was to evaluate the temperature change during low-speed drilling using infrared thermography. MATERIAL AND METHODS Pig ribs were used to provide cortical bone of a similar quality to human mandible. Heat production by three implant drill systems (two conventional drilling systems and one low-speed drilling system) was evaluated by measuring the bone temper...

This paper describes a new, environmentally friendly drilling technique for making shortand long-term access boreholes in shelf glaciers using lightweight drills. The new drilling technique was successfully developed for installation of small-diameter sensors under the Ross Ice Shelf through �193m thick ice at Windless Bight, McMurdo Ice Shelf, Antarctica. The two access boreholes were drilled ...

Underground tunnel face bolting and pipe umbrella reinforcement are one of the most challenging tasks in construction whether industrial or not, and infrastructures such as roads or pipelines. It is one of the first sectors of economic activity in the world. Through a variety of soil and rock, a cyclic Conventional Tunneling Method (CTM) remains the best one for projects with highly variable gr...

We show that crude oil production from existing wells in Texas does not respond to current or expected future oil prices, contradicting a basic prediction of Hotelling’s (1931) canonical model of exhaustible resource extraction. In contrast, the drilling of new wells exhibits a strong price response, as does the rental rate on drilling rigs. To explain these observations, we reformulate Hotelli...

Drilling engineering comprises a major part of production and exploration in oil fields and drilling risk is a significant ingredient to success. As one of the crucial ways to terminate oil spill event, relief well assumes great responsibility. Thus it is essential to analyze and assess the risk of relief well technique before drilling operation in order to guarantee rescue project work smoothl...

SUMMARY Mauve Contig Mover provides a new method for proposing the relative order of contigs that make up a draft genome based on comparison to a complete or draft reference genome. A novel application of the Mauve aligner and viewer provides an automated reordering algorithm coupled with a powerful drill-down display allowing detailed exploration of results. AVAILABILITY The software is avai...

the continuous development of global economy with decreasing in available hydrocarbon sources and increasing discovery and extraction costs due to decrease in-situ oil and gas reservoir, displays the necessity of using new techniques for the improve rate of penetration and productivity in well. nanotechnology has already contributed significantly to technological advances in the energy industri...

Due to temperature increase during bone drilling, bone necrosis is likely to occur. To minimize bone tissue damage during drilling, a detailed in vitro experimental study by using fresh calf cortical bones has been performed with various combined drilling parameters, such as: drilling environment, drill diameter, drill speed, drill force, feed-rate and drill coating. Bone temperatures at the dr...

Drilling is one of the most useful metal cutting processes and is used in various applications, such as aerospace, electronics, and automotive. In traditional drilling methods, the thrust force, torque, tolerance, and tribology (surface roughness) are related to the cutting condition and tool geometry. In this paper, the effects of a pre-center drill hole, tool material, and drilling strategy (...