Lateral Span Research Articles

せん断破壊性状が卓越する PRC 杭の強度と変形性能 : 長期軸力作用下における場合

This paper presents the results of the experimental tests completed to investigate the strength and the deformation capacity of Prestressed Reinforced Concrete pile (i.e., partially prestressed concrete pile) with shear failure. Eight specimens were tested; four with shear span to depth ratio of 1.5 and four with shear span to depth ratio of 2.0. The hollow space of each pile was filled with normal-strength concrete. The specimens modeled as the pile head were subjected to reverse cyclic loading under sustained axial load. The conclusions of this study are : (1) the deformation capacities of PRC piles with the different parameters (amount of lateral reinforcement and shear span to depth ratio) can be evaluated using the shear strength to flexural strength ratios, (2) PRC piles with the shear strength to flexural strength ratios more than 1.05 have the ultimate deformation angles more than 0.034rad.

Distributed Multi-Reasoning Mechanism to Support Conceptual Structural Design

The conceptual phase of structural design involves selecting preliminary materials, selecting the overall structural form of the building, producing a rough dimensional layout, and considering technological possibilities. Decisions are made on the basis of such information as height of the building, building use, typical live load, wind velocity, earthquake loading, design fundamental period, design acceleration, maximum lateral deflection, spans, story height, and other client requirements. More detailed information about the task itself, constraints, possible solution principles, and known solutions for similar problems is extremely useful in the process of defining and finding a solution to the design problem. This paper presents the M-RAM, which is intended to assist engineers in the conceptual phase of the structural design of tall buildings by providing designers with adapted past design solutions generated by a distributed multi-reasoning mechanism. The objective of the M-RAM (Multi-Reasoning Model...

Effect of Insect-proof Screens and Roof Openings on Greenhouse Ventilation

The object of this work was to determine and model the air exchange rate of greenhouses with insect-proof screens over the vents. Experimental tests were conducted on multi-span tunnel greenhouse with two types of ventilation openings, one with continuous roof vents and the other with an insect-proof screen which was able to replace a flexible roll-up plastic cover.Ventilation rates of the experimental greenhouses were measured using the tracer gas technique. Discharge coefficients were determined in a 1:3 scale model replica of the experimental greenhouses. A simple model that includes the global effect of the wind on the greenhouse ventilation was developed and compared with the measured air exchange values.The main results determine the reduction in the discharge coefficient when an insect-proof screen is incorporated. It was found that vents located in lateral spans have a higher discharge coefficient than those located in central spans. Some practical considerations for the design of more efficient ventilation systems can be derived from this fact.The global wind effect coefficient was found to be dependent on the type of vent, insect-proof screen and wind speed. Some results are not in agreement with others previously published, but obtained under different environmental conditions. This coefficient is derived from empirical measurements which makes its general application questionable.In spite of its simplicity, the theoretical model describes accurately the ventilation rate of the greenhouse with both types of vents. The roll-up roof vent provides a ventilation rate about three times greater than the continuous roof vent. It has an acceptable air exchange, while acting as a barrier against the entrance of undesirable pests.

Correction of the crooked nose.

Correcting the crooked nose remains one of the most challenging problems in rhinoplasty. When faced with a twisted nose, rhinoplasty surgeons tend to be divided into those who perform an anatomic reconstruction and those who prefer camouflage techniques. Regardless of the approach used, the revision rate remains fairly high. An anatomic correction of the twisted nose through an open approach was performed. The septum was freed from the extrinsic forces of the deformed nasal bones and upper and lower lateral cartilages. The residual true septal injury was then evaluated. The septal deformity was addressed through quadrangular cartilage resection, repositioning of the caudal septum in the anatomic midline, and correction of the dorsal septal deformity with horizontal control sutures. The skeletal support was then reconstructed with the use of a spreader-extension graft on the concave side and a batten graft on the opposite side. The nasal tip was set relative to the dorsum by fixation to the extension grafts. Residual lateral crus deformities were corrected by a combination of lateral crural spanning sutures or alar spreader grafts. With this approach, straightening the crooked nose without compromising skeletal support or nasal aesthetics was successful.

Frontal and Occipital Horn Ratio: A Linear Estimate of Ventricular Size for Multiple Imaging Modalities in Pediatric Hydrocephalus

Objective: Measurement of ventricular size is important in pediatric patients with hydrocephalus, especially those who are being followed with cerebrospinal fluid (CSF) shunts. While volumetric techniques are a more accurate estimate of true ventricular volume, they are often impracticable when multiple modalities including ultrasound are used. Volumetric area and linear measurements were compared to find the most reasonable measurement method. Methods: Sixty-four computed tomography (CT), magnetic reasonance imaging (MRI), and ultrasound (US) scans from 25 children aged 0–17 years with hydrocephalus, before and after treatment, were measured. Measurements included ventricular volume, a ventricular/brain ratio, and four standard linear measures (Evans’ ratio, Huckman’s measurement, minimal lateral ventricular width, and lateral ventricular span at the body). We also included a new ratio, which accounts for often disproportionate occipital horn expansion in pediatric patients, called the frontal and occipital horn ratio. Volume and linear measurements were compared using the Spearman’s correlation coefficients and correlations were further differentiated using a Z test statistic. The frontal and occipital horn ratio was also measured on CT, MRI, and US scans from 44 normal children aged 0–17 years to identify normal values. The effect of age was determined by linear regression. Results: The best linear correlation with ventricular size was the frontal + occipital horn ratio (r = 0.852) and was equivalent to the ventricular/brain ratio (r = 0.891), previously shown to have the highest correlation with ventricular volume. Evans’ ratio correlates less well (r = 0.423). The normal frontal and occipital horn ratio is 0.37 and is independent of age. Conclusions: The frontal and occipital horn ratio is a simple method of evaluating ventricular size in pediatric hydrocephalus patients with CSF shunts.

Evolving fixation methods in endoscopically assisted forehead rejuvenation: controversies and rationale.

The goals of surgical rejuvenation of the forehead include component brow manipulation, attenuation of transverse forehead rhytids, and reduction of glabellar frown lines. The endoscopic approach has proved successful in achieving these goals in selective patients while minimizing incisions and improving scalp sensation. Efficacy of endoscopic brow manipulation is dependent on (1) complete release of the brow at the supraorbital rim, (2) brow depressor muscle resection/release, and (3) tension-free fixation of the brow position until wound healing has occurred. Fixation of the brow using an endoscopic technique, unlike the open technique, is dependent on skin retraction and tension-free scalp fixation during the process of wound healing to maintain the desired brow position. Techniques for endoscopic fixation are arbitrarily divided into endogenous and exogenous. Endogenous methods include extensive galea-frontalis-occipitalis release, lateral spanning suspension sutures, external bolster fixation, anterior port skin excision, galea-frontalis advancement, cortical tunnels, and tissue adhesives. Exogenous techniques include internal screw or plate fixation, Mitek anchor fixation, external screw fixation, and absorbable K-wires. This article provides a goal-oriented review of these evolving techniques and a rationale for the use of fixation methods in endoscopically assisted forehead rejuvenation.

Lateral crural spanning grafts for the treatment of alar collapse.

Lateral crural spanning grafts for the treatment of alar collapse.

Effects of Nitrogen on the Development and Growth of the Potato Plant. 1. Leaf Appearance, Expansion Growth, Life Spans of Leaves and Stem Branching

Potatoes (Solamum tuberosum L.) were planted in pots in a temperature-controlled glasshouse to collect data on the rate of leaf apearance, leaf expansion, apical lateral branching and active life spans of leaves. The treatments consisted of three rates of nitrogen supply, i.e. the N1 treatment with 2.5 g N per pot and the N2 and N3 treatments with 8 and 16 g N per pot, respectively. The rate of leaf appearance was 0.53 leaves d -1 (one leaf per 28 o C d) and was negligibly affected by nitrogen supply. The rate of leaf expansion was related to leaf number and nitrogen supply

The magnetic topology of solar coronal structures following mass ejections

The bright radial structures observed in the solar corona for 1–2 days following a coronal mass ejection (CME) have traditionally been interpreted as unidirectional magnetic fields, commonly known as “legs,” at the sides of the ejections. We examine in detail the bright structures following 16 CMEs observed with the coronagraph on the Solar Maximum Mission (SMM) spacecraft and find that these structures can form anywhere within the lateral span of a CME, not only at the sides. We suggest that a more plausible interpretation is that the bright radial structures are the tops of coronal streamers containing magnetic neutral sheets across which the magnetic fields reverse direction. The observational support for this view is that: (1) the bright features left behind at CME sides, when a CME has left the field of view of this instrument, last <10 hours; (2) some bright radial structures form at the sites of preexisting streamers; (3) some such structures have the broad bases characteristic of helmet streamers; and (4) in several cases, narrow radial structures form over H α prominences. A reexamination of the structures observed in the Skylab era, including the well‐studied CME of August 10, 1973, reveals that they are also consistent with the streamer interpretation. This interpretation avoids several difficulties encountered with the “leg” interpretation: (1) the systematic brightening of legs −1 day after the CME; (2) the origin of the energetic electrons characteristic of stationary type IV bursts if they are associated with high‐density, unidirectional‐field structures unfavorable for particle acceleration; and (3) the lack of strong evidence of magnetic reconnection in the coronagraph data following CMEs.

A Self‐Propelled High‐Clearance Soil Coring Machine1,2

AbstractMechanical soil sampling equipment currently available is suitable for sampling prior to crop establishment or in low growing crops but cannot be used without plant damage in some tall crops. A self‐propelled high‐clearance soil coring machine was designed and constructed to obtain soil samples in a tall standing crop at a range of lateral as well as vertical distances. The sampler is hydraulically operated and has vertical pressure and rotary drilling capabilities. This equipment has a lateral travel span of 152 cm and the capability of coring to a depth of 9 m with the mast in any lateral position on the track. Two operators can use the sampler without difficulty; however, three operators are desirable if a large number of samples are to be taken. As many as eighty 30‐cm increment soil samples have been taken per hour when sampling a moist sandy soil to a depth of 2 m.

Cognitive style, hemispheric specialization, and tested abilities of transsexuals and nontranssexuals.

Tests on which the 12 males and the 8 male transsexuals differed significantly and might be useful to clinicians for differentiation were the Embedded-figures Test, the Porteus Mazes, and the O'Connor Finger Dexterity Test. Sex differences emerged on the Embedded-figures Test and the first half of the dexterity test. There were no significant differences between 12 males and 14 females or males and 8 transsexuals on conjugate lateral eye movement, eye dominance, Digit Span, and Digit Symbol. Embedded-figures Test appears to tap some aspect of gender identity (males with female identities respond like females) while the first half of the O'Connor taps a biologically determined sex difference (males respond alike whether they have male or female identities).

Nuevo puente de La Barca sobre el río Ter

The new La Barca bridge, over the river Ter, is on the northern approach to Gerona, and carries the CN II road from Madrid to France, passing through Barcelona. It substitutes another bridge of the same name, which was inadequate for the heavy increase in traffic, during recent years. The bridge is 128 m long, consisting of two lateral spans, each 37 m long, and a central span of 54 m. The superstructure consists of ten hollow metal girders, of variable depth, arranged as three-part cantilevered structures. The lateral sections are cantilevered towards the centre, and the middle part of the span rests on their extremities. The girders support a reinforced concrete slab of 16 cm thickness and 14 m width: 8 m for the roadway, and 3 m for each of the sidewalks. The structure rests on two piles and two abutments of reinforced concrete, based on caisson foundations, except for one of the abutments, which is a reinforced concrete block. The project is completed by the approach roads and stonemasonry.

Puente, en Hagen

The bridge at Hagen-Eskesy, in Germany, was destroyed during the last war, and its reconstruction is part of a local improvement plan. The initial bridge was metallic, but it has now been decided to build a main tied arch, consisting of a box section arch, of 93 m span, and two lateral spans, each 33 m long. These two are open girders, whose top and bottom chords are also hollow box sections. Both the tie members and the main bridging structures are prestressed. The twin arches, from which the deck hangs, are independent. This has made it necessary to attach the arches very rigidly to the stabilising structure, to withstand the powerful effect of the wind forces. Owing to the large dimensions, the possible effect of torsion and buckling under the prestressing forces had to be carefully considered. The twin arches are 12.90 m from each other, and their section is 1.2x1.2 m at the springers, 2x2 m at the quarter span, and 2.4x1.7 at the crown. During the loading and overloading tests, oscilographs were used, to record the effect of mobile loads, and of the increasing overloads. To simulate the effect of running over uneven surfaces, timber beams were placed across the pavement, and loaded vehicles were made to run over them.