Recovery from disturbance in deep water is poorly understood, but as anthropogenic impacts increase in deeper water it is important to quantify the process. Exploratory hydrocarbon drilling causes physical disturbance, smothering the seabed near the well. Video transects obtained by remotely operated vehicles were used to assess the change in invertebrate megafaunal density and diversity caused...

PURPOSE To compile the current evidence on biomechanical, biologic, and clinical outcomes of undersized surgical preparation protocols in dental implant surgery. MATERIALS AND METHODS An electronic search using three different databases (PubMed, Web of Science, and Cochrane Library) and a manual hand search were performed including in vitro, animal, and clinical studies published prior to Oct...

In the paper the main attention is paid to conditions on algebras from a given variety Θ which provide coincidence of their algebraic geometries. The main part here play the notions mentioned in the title of the paper.

Purpose: Machining fixtures must fit exactly the work piece to support it appropriately. Even slight change in the design of the work piece renders the costly fixture useless. Substitution of traditional fixtures by a programmable multi-robot system supporting the work pieces requires a specific control system and a specific programming method enabling its quick reconfiguration. Design/methodol...

Embedded sensors, connected to the industrial internet of things (IIoT), have increased the granularity and frequency of data collected during the drilling process – but the data is often siloed and underutilized. This lack of integration can lead to expensive, time-consuming problems during the drilling process. Inefficient drilling programs can have an even greater aggregate financial impact,...

Drilling holes into concrete or metal ceilings is one of the most physically demanding tasks performed in construction. The work is done overhead with rotary impact hammer drills that weigh up to 40 N. The task is associated with pain and musculoskeletal disorders at the wrist, forearm, shoulder, and back. The mechanism of injury is thought to be the high forces and non-neutral shoulder and wri...

A convolution integral is developed to evaluate transient, drilling speed-dependent discharge rates into a tunnel gradually excavated in a homogeneous infinite aquifer. Comparison with the classical instantaneous-drilling evaluation commonly used in practice reveals drastically reduced early-time discharge rates, higher maximum rates, and similar long-term rates. Dimensionless-type curves are p...

the narrow operating window between pore pressure and fracture pressure makes drilling difficult in some operations. a feasibility study of managed pressure drilling (mpd) is carried out on iran darquain oil field. the previous wells drilled in this field showed that mud returns were lost during drilling gadvan formation. the present work addresses this problem by means of surface back pressure...

Bone drilling is a common procedure to prepare an implant site during orthopaedic surgery. An increase in temperature during such a procedure can result in thermal ostenecrosis which may delay healing or reduce the stability of the fixation. Therefore it is important to minimize the thermal invasion of bone during drilling. The Taguchi method has been applied to investigate the optimal combinat...