Diagonal Wires Research Articles

Optimization of grid configuration by investigating its effect on positive plate of lead-acid batteries via numerical modeling

With increasing the applications of lead-acid batteries, the demand for efficient, low resistant and inexpensive batteries has increased drastically. As discharge rates increase, ohmic voltage losses in current collecting system become more important. In this study, numerical methods are employed to investigate the effect of grid configuration, lug position, diagonal wire angles and tapering wires towards the plate’s lug on the performance of positive electrode of lead-acid batteries via modeling the current and potential distribution through gird wires, active material and adjacent electrolyte to the surface of each grid. 18 distinct grid designs with same weights are designed to achieve this task. The results indicate that double-diagonal configuration offers up to 43% increased current distribution uniformity. It is also shown that locating the lug near the midpoint of the frame, increasing the degree of parallel diagonal wires and tapering the wires towards the lug increases the uniformity of the current distribution up to 14%, 1.6% and 5.6%, respectively. It is noteworthy that manufacturing and practical limitations has been taken into account in this work as well.

Effects of palate depth, modified arm shape, and anchor screw on rapid maxillary expansion: a finite element analysis.

This study examined the effects of palate depth, modifications of the arm shape, and anchor screw placement in the mid-palatal area on rapid maxillary expansion (RME) using finite element (FE) analysis. Three-dimensional FE models were constructed that included the maxilla (cortical and cancellous bone), maxillary sinus, maxillary first molar and first premolar, periodontal membrane, and an RME appliance with arms, bands, and anchor screws. The expansion screws were activated 0.2mm transversely. The deepest palate model had the smallest lateral displacement of the tooth and expansion of the mid-palatal suture and the greatest strain of the arm among the models with different palate heights. The model with a larger diameter arm had the smallest arm strain among the models with various arm shapes. The model with an anchor screw had the greatest lateral displacement of the tooth and expansion of the mid-palatal suture among all models. For a deeper palate, the arm strain increased and the effect of RME decreased. Modified arm shapes such as a larger diameter arm, arms connected by a diagonal wire, a straight arm, and a shorter arm efficiently expanded the maxillary dental arch. Anchor screws increased the effect of RME, generated more and closer bodily movement of the tooth, and parallel expansion of the mid-palatal suture. The model with an anchor screw without arms decreased the displacement of the teeth compared to the models with arms, so the arms are necessary for effective RME.

Characteristics of an isotropic 3-dimensional left-handed metamaterial composed of wired metallic spheres

Electromagnetic wave propagations in a 3-dimensional (3D) left-handed (LH) metamaterial composed of periodic wired metallic spheres are studied numerically. It is shown that the metamaterial supports the dominant 3D LH wave with negative refractive indices. Parametric studies of dependencies of the dispersion characteristics on the unit cell structure are carried out and it is shown that the isotropy can be enhanced by tuning the diagonal wire diameter and the sphere diameters.

Evaluation of X Architecture Using Interconnect Length Distribution

In this paper, we propose a new Interconnect Length Distribution (ILD) model to evaluate X architecture. X architecture uses 45°-wire orientations in addition to 90°-wire orientations, which contributes to reduce the total wire length and the number of vias. In this paper, we evaluated interconnect length distribution of diagonal (45° orientations) and all-directional wiring. The average length and the longest length of interconnect are estimated, and 18% reduction in power consumption and 17% improvement in clock frequency can be obtained by the diagonal wiring in the experimental results. The all-directional wiring does not have large advantage as compared the diagonal wiring.

Lightning Surge Analysis Including Diagonal Wires Based on the FDTD Method

This paper presents an arbitrary diagonal wire on an rectangular surface composing a cubic cell in an electromagnetic analysis based on the orthogonal FDTD (Finite-Difference Time-Domain) Algorithm. One of the numerical electromagnetic analyzing algorithms is the FDTD method based on Maxwell’s equation. The basic FDTD method divides the analyzed space into cubic cells and directly calculates the electrical and magnetic fields of the cells by discretizing the Maxwell’s equation of electromagnetic fields, where the derivatives with respect to time and space are replaced by a numerical difference. The development of computer performance brings about an actual execution of the FDTD method on a usual personal computer recently.In dealing with a diagonal and curved wire, the boundaries of which do not coincide with the finite-difference grid lines, the staircase approximation has been commonly used. However, the approximation causes the large error in a resonant frequency and a propagation time of a system including the diagonal or curved wire. The proposed method can express a diagonal and curved wires on a rectangular surface composing a cubic cell by transforming the general integral form of Maxwell’s equation to the different integral form around the wires. This proposed method is also useful to calculate surge propagation on an arbitrary three-dimensional skeleton structure including a diagonal or curved grid such as a tower model and so on.

Nearly optimal algorithms and bounds for multilayer channel routing

This paper presents algorithms for routing channels with L ≥2 layers. For the unit vertical overlap model, we describe a two-layer channel routing algorithm that uses at most d + O(√d) tracks to route two-terminal net problems and 2d + O(√d) tracks to route multiterminal nets. We also show that d + Ω(log d) tracks are required to route two-terminal net problems in the worst case even if arbitrary vertical overlap is allowed. We generalize the algorithm to unrestricted multilayer routing and use only d/(L -1) + O(√d/L + 1)> tracks for two-terminal net problems (within O(√d/L + 1) tracks of optimal) and d/(L-2) +O(√d/L + 1) tracks for multiterminal net problems (within a factor of(L-1)/(L-2) times optimal). We demonstrate the generality of our routing strategy by showing that it can be used to duplicate some of the best previous upper bounds for other models (two-layer Manhattan routing and two and three-layer knock-knee routing of two-terminal, two-sided nets), and gives a new upper bound for rotuing with 45-degree diagonal wires.

Distal internal carotid exposure: A simplified technique for temporary mandibular subluxation

Distal internal carotid artery exposure can be technically demanding even for experienced vascular surgeons. Although a variety of techniques have been described to facilitate such exposure, temporary mandibular subluxation has emerged as the simplest and least debilitating approach. Current techniques for maintaining temporary mandibular subluxation during distal internal carotid artery procedures, including maxillomandibular arch bar fixation and circummandibular/transnasal wiring, have been time consuming and associated with complications. Over the last 4 years a new simplified technique of temporary mandibular subluxation fixation has been used in 14 patients requiring distal internal carotid exposure. Indications for operation included extended carotid endarterectomy (8), carotid body tumor excision (2), repair of distal internal carotid artery trauma (2), and repair of postendarterectomy pseudoaneurysm (2). Among patients with healthy teeth, unilateral temporary mandibular subluxation was maintained by interdental wiring from the ipsilateral mandibular bicuspids to the contralateral maxillary bicuspids. In edentulous patients or those with chronic periodontal disease, temporary mandibular subluxation was maintained with diagonal wiring between maxillary and mandibular Steinmann pins. No instances of malocclusion, dental injury, or local infection were observed. Transient postoperative cranial nerve dysfunction was observed in three patients. Transient ipsilateral temporomandibular joint pain occurred in three patients. Two patients developed permanent cranial nerve injuries unrelated to temporary mandibular subluxation. These data suggest that temporary mandibular subluxation by diagonal interdental/Steinmann pin wiring is safe, expeditious, and effective in facilitating exposure of the distal internal carotid artery.

Two terminal channel routing using at most density plus two tracks

In this paper an algorithm is presented for routing a restricted class of channel routing problems in at most density plus two tracks. The underlying hardware model uses two layers of interconnect and supports orthogonal and diagonal wires. The essence of this model and the channel routing problems on this model are captured in a graph representation over a grid. The main part of this paper consists of a proof of this algorithm and its performance guarantee.

High‐density wiring technology in multiwire boards

AbstractThis paper considers the recent requirement for high‐density packaging technology and discusses the high‐density wiring technique for the Multiwire board. A proposal is made for the wiring rule as well as the fundamental manufacturing processes, which can realize twice higher wiring density compared with the traditional method. The Multiwire wiring employing the insulated wires as conductor can realize the wire crossings on the same plane. However, the technique has the following problem. When thin wire is used and the wiring pitch is reduced to realize a high‐density wiring, the strength of the wire is reduced, its adhesion to the board is degraded, and an interference with the adjacent wire due to stylus is produced. Then there are dangers of producing such defects as wire breakage, floating wire, position shift and flaws in a wire insulator. Those phenomena place a limit on the high‐density implementation by reduciong of the wiring pitch. From such a viewpoint, the diagonal wiring is newly utilized positively, leading to the wire breakage prevention at three or four wire crossovers which has a high breakage probability. Based on the estimation of the number of terminals and the terminal pitch of the LSI package in the future, the required wiring density is calculated. The industrially practical accuracy is assigned to the manufacturing processes, and considering those situations, the high‐density wiring rules are discussed. As a result, the following wiring rules are derived. The through‐holes are located by a 2.54‐mm grid and at the center, and eight passings (five orthogonal plus three diagonal) in a 2.54‐mm grid can be made as the highest wiring density. In addition, some intermediate wiring rules for five, six and seven passings are also presented. An example is shown in which the new wiring rule is applied to the product based on those investigations.

The Airship for the British Navy

THE leading article in Engineering for February 17 gives some account of the airship for the British Navy built by the Vickers Company at Barrow. Trials were conducted on Tuesday, February 14, in presence of the Government's Advisory Committee on Aëronautics, these being analogous to the basin trials of a warship, and have proved to be quite satisfactory. The structure for accommodating the hydrogen reservoirs or balloons is 512 feet in length and 48 feet in diameter. It is in the form of a decagon in section, and the. ten sides are built up of' longitudinal lattice-girders, with vertical intercostal girders, the top and bottom boom in each case being formed of angles or tees of duralumin. Each bay has diagonal wire bracing. The form is whale-like, with a bluff entry, and a sweet run aft to a point, where, at the bottom, there is a big fin, increasing in depth aft according to the upward rise to the point of the stern. Aluminium was first tried, but the girder structure of this metal collapsed under stress. The metal adopted—duralumin—is one of the magnesium alloys of aluminium, and contains 91 per cent, of aluminium. It has a specific gravity between 2.77 and 2.84, a melting point of about 650° C., a yield point varying from 12 to 16 tons per square inch according to the hardness, and a breaking resistance from 22 to 29 tons per square inch. The elongation varies from 23 to 18 per cent., and the contraction of area from 34 to 26 per cent. It will thus be seen that, despite its lightness, it bears comparison with mild steel.