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This paper discusses the rear left-hand occupant’s injury during frontal oblique collision with PRESYS software. Based on the simulations among different frontal oblique angles (10 ∼ 50 °) and occupant constraint system models, the injury of rear left-hand dummy are analyzed at an initial collision speed of 50 km/h. It is found that the impact on the occupant’s dynamic responses (acceleration and shear forces) by the seat belt is significant and depends upon the oblique angle. With the given vehicle and collision speed, it is observed that the seat belt can effectively reduce the occupant’s head acceleration and the neck longitudinal (Fx) shear force if the collision angle is between 10 ° and 20 °. However, the seat belt increases the occupant’s head resultant acceleration when the collision angle is between 35 ° and 40 °. In addition, when the collision angle is between 10 ° and 50 °, the seat belt can also effectively reduce the occupant’s chest acceleration. At most collision angles, the seat belt can effectively reduce the overall damage of rear row left occupant in frontal oblique collision, but the WIC (Weighted Injury Criterion) value of the rear row dummy with seat belt is still very large at the collision angle below 30 °. Therefore, the restraint system of the rear row occupants needs to be improved.

The present study attempted to improve the discharge capacity of oblique weirs by rounding their crests. Twenty-four oblique weir models have been tested in which oblique angle (α), weir height (P) and crest diameter (D) were changed. Analysis of the results shows that the discharge (QOC) increases with the increase of effective head above crest (He). Values of discharge coefficient (CD) are found decreasing slightly with the increase of (He/P) and (He/D) values and weirs of small oblique angles give lower values of CD. An empirical expression is presented to determine CD in terms of He/P, He/D and α (in radian) with a correlation coefficient of 0.90 and a standard error of 0.01. The highest discharge capacity is obtained from a weir having α = 20°, P = 20 cm, D = 4 cm and D/P ratio = 0.2 in which the percentage increase in discharge is ranging between 147% and 175% compared to sharp crested normal weir. Comparison of the present study results with those of other investigations shows that circular crested oblique weirs offer higher discharge capacity compared with some other weir shapes. A simple design method is recommended through which the lasting dimensions and the head-discharge relationship of the weir can be predicted.

This article is devoted to the study of the oblique fall of an acoustic wave from a pure gas to the boundary of a multifraction gas suspension with polydisperse inclusions of different sizes and materials. A mathematical model that allows to determine the reflection coefficient when an acoustic wave falls obliquely on the interface between two media is presented. Dependencies of the reflection coefficient on the disturbance frequency were calculated. Influence of the oblique angle of acoustic wave on the dependence of the reflection coefficient was established.

In this paper, preloading on plates and obliquity in impacts are brought together in order to achieve more realistic conditions for the plates such as in aerospace applications. A numerical model was established to simulate the oblique impact on preloaded aluminum plates. In the design of impacts, numerical simulations were carried out using three variable parameters namely preloading condition, oblique angle and impact velocity. Based on the results, preloading leads to crack initiations on the plates due to sharp edges around the perforation holes. On the other hand, full perforation is observed at low oblique angles however, deformation mode turns to tearing by increasing obliquity of the plates. Impact velocity is another important factor on the impact resistance of the plates. Despite high oblique angles, the plates can be perforated under high-velocity impacts.

An Australian network of oblique angle-of-arrival (AoA) ionosondes was installed as part of the ELOISE experimental campaign in September 2015, aimed at an improved understanding of the spatial and temporal structure of traveling ionospheric disturbances (TIDs) at mid-latitudes. In this paper, the array design and signal processing for the AoA sounder is described, along with a sample of results showing typical disturbance signatures. Realistic parameterized models of electron density perturbations, along with geometric ray tracing, were used to synthesize the effects of medium to large scale TIDs on the sounder observables and aid in classifying the measurements.

A new process for simultaneous generation and positioning of microdroplets within a single step named oblique interface shearing (OIS) is reported based on the observation that liquid microdroplets generated by vibrating a thin capillary across the air-liquid interface at an oblique angle exhibit notable lateral displacements. An analytical model is established to describe the lateral droplet displacement induced by the Stokes drift effect. The dependency of the lateral displacement on typical operating parameters allows for on-demand droplet positioning while they are produced. The efficacy of the process is validated through delivering microdroplets with the same size to different positions as well as size-dependent positioning of these microdroplets.

During development testing of a 12.5 kW magnetically shielded Hall thruster, direct evidence of counterstreaming ions eroding the pole covers was found. One stream of ions appears to originate from the discharge channel while the other stream appears to originate from the centrally mounted cathode. Velocity distribution measurement indicates that each stream impacts the poles of the thruster at high oblique angles of incidence. While the average energy of each stream was in the tens of eV, the energy distributions contained high-energy tails that can be a major contributor to erosion. Starting with the physical picture of high oblique angle bombardment, predictions of change in erosion behavior over time are in good agreement with pole cover erosion measurements taken during wear testing. The new evidence points to a need to study these ions that are traditionally considered “low-energy” ions and the role they play in the erosion of the poles of magnetically shielded Hall thrusters.

The prepsoas oblique approach to the lumbar spine provides many similar benefits of the transpsoas lateral approach. Because the psoas is not traversed, however, many of the postoperative complications associated with psoas violation are reduced. Working at an oblique angle to the spine can be challenging and the approach may be unfamiliar for the surgeon. Thais article provides a technical description and nuances of the approach.

Linear dunes are the most common dune form found on planetary surfaces, yet questions remain about their formation. Temporal observations of a linear dune located in the Simpson Desert of central Australia were made to monitor dune movement and to test competing hypotheses regarding linear dune formation. Our observations were collected on three separate occasions from 2006 to 2014. Rebar stakes were placed in a gridded pattern so that multiple measurements of sand thickness, GPS surveys, and photographs could be taken at the same locations over time. We observed widespread reworking of sand on and around the dune crest, with sand accumulation locally exceeding a meter between surveys. Overall, the height of the dune crest increased by several centimeters. We also observed fluctuations in the sand cover in the adjacent swales that often exceeded 2–3 cm between surveys, yet we did not observe any appreciable changes in the position of the dune's downwind terminus. Weather data indicate that the effective sand-transporting winds in the Simpson are widely unimodal. Net sediment flux (resultant drift direction) is toward the north-northwest, locally at an oblique angle to dune orientation. Collectively, our results suggest that the linear dune is actively maintained by vertical accretion. The implications from our observations are that linear dunes on other planetary surfaces could form in wind regimes that are widely unimodal, even where the resultant drift direction is locally oblique to dune orientation. In particular, such findings may provide support for global circulation models of Titan.

Background: This study sought to determine safe ranges of oblique angle, skin entry point and needle length by reviewing computed tomography (CT) scans and to evaluate the usefulness of a bent tip needle during celiac plexus block (CPB). Methods: CT scans of 60 CPB patients were reviewed. Image of the uppermost margin of L2 vertebral body was used to measure the minimal and maximal oblique angles and the distances from the midline to skin puncture point. The imaginary needle trajectory distance was calculated by three-dimensional measurement. When the procedure was performed by using a 10o bent tip needle under a 20o oblique X-ray fluoroscopic view, the distance (GF/G’F) from the midline to the actual puncture site was measured. Results: The imaginary safe oblique angle range was 26.4.34.2o and 27.7.36.0o on the right and left, respectively. The distance from the midline to skin puncture point was 6.1.7.6 cm on the right and 6.3.7.6 cm on the left. The needle trajectory distance at minimal angle was 9.6.11.6 cm on the right and 9.5.11.5 cm on the left. The distance of GF/G’F was 5.1.6.5 cm and 5.0.6.4 cm on the right and left, respectively. All imaginary parameters were correlated with BMI except for GF/G’F. All complications were mild and transient. Conclusions: We identified safe values of angles and distances using a straight needle. Furthermore, using a bent tip needle under a 20o oblique fluoroscopic view, we could safely perform CPB with smaller parameter values. (Korean J Pain 2015; 28: 109-115)

The bounce of a ball is a seemingly innocuous event that can be used to illustrate many aspects of elementary and even advanced mechanics. Both normal and oblique bounces on a rigid surface are considered in this article, emphasizing qualitative features of the bounce process. If the ball bounces at an oblique angle then it can slide throughout the bounce, or just at the start of the bounce, and may even slide backwards at the end of the bounce. A ball can also grip the surface after a short sliding phase, or it can grip right from the start. When the ball grips, static friction rather than sliding friction determines the rebound speed, spin and angle.

Micro fluidized bed is a promising reactor for a variety of industrial processes. It is important to understand the hydrodynamics of gas-solid fluidization of the micro fluidized beds with different oblique angles. This study numerically investigated the effects of oblique angle on the fluidization behavior and pressure drop in the micro fluidized beds by Computational Particle-Fluid Dynamics (CPFD) models. The results show that the oblique angle of the bed affects strongly the particles, fluidized gas and pressure distribution in the micro fluidized bed due to strong wall effects. The bed with oblique angle of 0° can achieve better gas-solid contact than the inclined beds. The pressure drops in the micro fluidized beds decrease linearly with increasing oblique angles of the beds when the oblique angles are beyond 15°. The oblique angle of the bed has a great influence on the fluidization behavior and pressure drop in the micro fluidized bed.

An analytical study on controlling quantum breathers in one-dimensional ferromagnetic XXZ spin chains through an oblique magnetic field is presented in this paper. Based on the time-dependent Hartree approximation and the semidiscrete multiple-scale method, we prove the existence of quantum breathers, analyze conditions for their appearance, and discuss their properties. Our results show that the appearance and features of quantum breathers can be controlled by varying the value of the oblique angle θ.

This paper presents the simulation of the bone healing process of a fractured tibia with oblique angles according to plate modulus and initial loading condition by FE analysis. To simulate tissue differentiation and the pathway of development of the curing cells during the healing process, a mechano-regulation theory on deviatoric strain is introduced. For the iterative calculation to determine cell phenotype during the healing period, a user subroutine was programmed by Python code. The analysis result revealed that the healing efficiency was strongly affected by the initial loading condition and the coupling of the plate’s modulus with the oblique angle. By FE analysis, the most appropriate plate modulus for each initial load condition and oblique angle was suggested.

To determine the individual values of the two strain components by separate principal strains, a theoretical model of strain separation by oblique incidence with a new luminescent photoelastic coating configuration is presented. Considering the non-strain related refraction effect included in the total optical response at oblique incidence, the small incidence angle technique for simplifying the post-processing complexity is given. To affirm the validity of this strain separation method based on small oblique angles, the signal-to-noise ratio for providing sufficient signal intensity has been theoretically analyzed.

Previous studies highlighted the need to develop efficient harvesting and size reduction equipment for miscanthus. This study investigated the effect of blade oblique angles and cutting speeds on cutting energy. Cutting blade speed, before and after severing a single miscanthus stem, was used to calculate the cutting energy. The cutting energy was determined at three oblique angles and three cutting speeds. A 60° oblique angle cut required the least energy to cut miscanthus stems averaging about 7.6 J whilst a 30° oblique cut averaged 8.7 J and a straight cut averaged 10.1 J. In general, the 60° oblique cut performed best since it required average lowest specific energy (energy per unit of stem diameter) of 741.9 J m−1 at an average cutting speed of 12.9 m s−1. The specific cutting energy was directly proportional to the cutting speed and cutting energy was proportional to the stem diameter. The results indicate that optimisation of cutting speed and blade oblique angle will result in significant energy savings and increased efficiency of miscanthus harvesting machinery.

A comprehensive set of experiments was performed on weirs placed obliquely in a rectangular open channel. The main objectives were to investigate the effect of the weir angle relative to the approach flow direction on the behaviour and the hydraulic flow characteristics and to examine methods such as using upstream guide vanes and inclined aprons to increase the effective oblique weir length. Results indicate that by increasing the oblique angle, the effective length of the oblique weir increases significantly. Relationships are provided for the threshold submergence and the effective length of the oblique weir. Design recommendations are also presented for the use of guide vanes and upstream inclined aprons.

Experiments have been carried out on models of free-to-rotate parallel and oblique plates fitted to a rigid section of circular cylinder to investigate the effect of plate length and oblique angle on the stability of this type of VIV suppressor. Measurements of the dynamic response by trajectories of motion are presented for models with low mass and damping, free to respond in the cross-flow and streamwise directions. It is shown that, depending on a combination of geometric parameters devices might not be able to completely suppress VIV for the whole range of reduced velocities investigated. Plates with larger oblique angles turned to be less stable than parallel plates and induced high-amplitude vibrations for some specific reduced velocities.

The flow field of industrial ventilation hood induced by the combination of extract-flow and crosswind will be affected by the oblique angle of the hood's set-up. This text is aimed at the oblique effects of a hood computed numerically by the I-DEAS ESC software. The size and scope of the capture zone of toxic gases upon the flow simulation are highly influenced by the variables of the extract velocity at the opening to the extract duct and the angle of the opening of the duct to the direction of the environmental air flow. The streamline extending from the hood's central axis is changed. The efficiencies of gas capture are altered not only by the momentum ratio u/v but also by the relation between the direction of the hood's inclination and crosswind vector.

To establish a Altari radish pre-processing system far kimchi, the leaves and root tail of the Altari radish cutting de-vices were developed. The cutting resistances depend on the edge angles, oblique angles and cutting speeds were measured and analyzed. The experiments were performed to reveal the optimal conditions that showed the minimum cutting resistances acting on the materials. As the results, the optimum conditions that acting on the leaves were at edge angle , oblique angle and cutting speed 0.5 m/s, and those acting on the root tails were at edge angle , oblique angle and cutting speed 0.5 m/s, respectively. Considered a safety conception, the oblique angle of the leaves cutting device was adjusted as , and then the cutting efficiencies of the both devices at these conditions were showed perfect performances.

FeNi thin films were fabricated by radio frequency magnetron sputtering on Si(1 1 1). Dynamic properties at remanence of the films were systematically investigated in a wide frequency range from 100 MHz to 5 GHz. The results show that both thickness of FeNi films and oblique angle have important effects on the magnetic properties of the films, the magnetic resonant frequency of the films can also be adjusted by the two factors. The in-plane uniaxial magnetic anisotropy field can be adjusted from 82 Oe to 220 Oe by increasing the oblique angle. As a consequence, the magnetic resonant frequency of the films increased from 2.7 GHz to 4.2 GHz.

The objective of this study is to numerically investigate the 3-D confined turbulent twin circular jets impinging to an inclined moving plate submerged in quiescent water. The effects of different dimensionless plate velocities (Up = −0.2, −0.1, 0, 0.1, 0.2), and the oblique angles (θ = 0°, 10°, 20°, 30°), with Up = 0 and θ= 0° being the conventional vertical jet impingement to a stationary plate, on the velocity field and heat transfer phenomenon were investigated in detail. It is shown that the plate moving direction has tremendous effect on the local and average Nusselt number distributions. In the case of stationary plate (Up = 0), the average Nusselt number is decreased as the plate oblique angle θ is increased. For a positive normalized plate velocity (Up>0), the average Nusselt number is decreased with increasing oblique angle θ, while for a negative normalized plate velocity (Up

The Talbot effect is investigated for oblique angles of illumination. From the transfer function of free space assuming small diffraction angles we calculate the self-imaging condition for periodic diffractive elements. Additionally, aberrations are considered, which are of third order in spatial frequency. These aberrations originate from the asymmetric off-axis configuration and cause distortions of the self-images. We include experimental verifications of our considerations and suggest applications of the off-axis Talbot effect to planar optics.

The objective of the experiments in this paper is to find out the relationship between cutting forces and oblique angles of cutting edge. The experiment consists of 90°−0° and 0°−90° oblique cutting situations. Each type of experiment includes two wood species and two kinds of chip thickness. As a result of the experiments, the influences of oblique angle and other factors on cutting forces were revealed. The reasons for cutting forces variations were summarized. On the basis of this, we especially conducted theoretical analyses on the rules of cutting forces change.

It has been found that at the electrohydrodynamic convection in the hybrid aligned nematics the oblique rolls are formed. These patterns are not stationary. The dependencies of the threshold voltage, drift velocity of rolls and oblique angle on the frequency of the AC electric field have been measured.

An indoor experiment was conducted to analyze the movement characteristics of different sized droplets and their influence on water application rate distribution and kinetic energy distribution. Radial droplets emitted from a Nelson D3000 sprinkler nozzle under 66.3, 84.8, and 103.3 kPa were measured in terms of droplet velocity, landing angle, and droplet kinetic energy and results were compared to natural rainfall characteristics. Results indicate that sprinkler irrigation droplet landing velocity for all sizes of droplets is not related to nozzle pressure and the values of landing velocity are very close to that of natural rainfall. The velocity horizontal component increases with radial distance while the velocity vertical component decreases with radial distance. Additionally, landing angle of all droplet sizes decreases with radial distance. The kinetic energy is decomposed into vertical component and horizontal component due to the oblique angles of droplet impact on the surface soil, and this may aggravate soil erosion. Therefore the actual oblique angle of impact should be considered in actual field conditions and measures should be taken for remediation of soil erosion if necessary.

A virtual prototype of oblique rotary tilling based on SPH(Smooth Particle Hydrodynamics) was developed. Digital simulation and field test of oblique rotary tilling were conducted. The digital simulation suggested that soil mainly was torn to failure during oblique rotary tilling. Therefore, oblique rotary tilling could save energy. The given power consumption comparison of digital simulation and indoors test verified the virtual prototype. The optimization value of oblique angle and phase angle was given when rotary velocity equals 200rpm and working velocity equals 0.4m/s based on simulation. By simulating throwing soil during rotary tilling, the result suggested that the velocity of soil thrown was not uniform but lean to tangent blade’s direction. This simulation result should be taken into consideration while designing oblique rotary tiller. Furrow bottom shape was figured out by simulating, too. The convex height was about 9.6% of tilling depth. All of the research result suggested that oblique rotary tilling might be a very potential tilling method which could save tilling energy greatly.

A new oblique-shaped end-tab was investigated for use in testing off-axis coupon specimens. This tab is able to ensure the axial displacement that is necessary in off-axis specimens under uniaxial loading. The explicit expression of the oblique angle was obtained as a function of the off-axis angle and composite properties. Finite element analysis and experiments were performed to evaluate the effectiveness of the oblique tab. Both results indicated that the oblique tab is more suitable than the conventional rectangular tab for uniaxial off-axis testing.

Avaliaram-se a capacidade de produção e o consumo específico de energia em picadoras de forragem tipo Desintegrador/Picador/Moedor no processamento de capim-elefante considerando-se, como tratamentos, três picadoras (DPM-1, DPm-2 e DPM-4), cinco diferentes rotações, três ângulos oblíquos das facas e dois ângulos do gume das facas. O delineamento experimental foi o inteiramente casualizado com duas repetições e os resultados avaliados por meio da análise de regressão. O ângulo oblíquo de 10º propiciou, aos três DPMs, maior eficiência e, em algumas situações o ângulo oblíquo de 38º proporcionou melhor desempenho aos DPMs 1 e 2; enquanto em outras, o ângulo de 30º proporcionou ao DPM-4, melhor desempenho. É possível baixar o custo de produção quando se trabalha em menores rotações, em virtude do valor do consumo específico ser reduzido. Embora o DPM-4 tenha apresentado menor demanda energética, ressalta-se que esta máquina possui maior preço de aquisição que os outros dois modelos e maior dificuldade de alimentação, obrigando o produtor a contratar mais uma pessoa para executar este processo. The production capacity and specific energy consumption in forage choppers type Disintegrator/Chopper/Grinder for elephant grass processing were evaluated. The treatments consisted of the combination of three forage choppers (DPM-1, DPm-2 and DPM-4), each operating in five different rotations, three oblique angles of the knives and two angles of the knives' edges. The experimental design used was completely randomized with two repetitions, and the results were evaluated by means of the regression analysis. The oblique angle of 10º led to greater efficiency for the three DPMs. In some situations, the oblique angle of 38º provided better performance for DPMs 1 and 2, while in others, the angle of 30º provided better performance for DPM-4. It is possible to lower production costs, when working at lower rotation speeds, due to the specific consumption being reduced. Although the DPM-4 has presented a lower energy demand, it is worth pointing out that this machine is more expensive than the other two models and presents greater difficulty in feeding, forcing the farmer to employ an extra person to execute this process.

In order to aid in engineering design and modification of cutting mechanisms in soybean harvesters and to investigate the effects of parameters on cutting energy, an impact shear test apparatus was designed and constructed to measure the energy required for cutting soybean plant stems. Experiments were carried out on Iranian Sahar variety, in different blade velocities (2.5, 3.75, 4.5 and 5.45 m s(-1)) to determine the optimum values of blade bevel angles (18, 23, 28, 33 and 38 degrees), oblique angles (10, 20, 30, 40 and 50 degrees) and tilt angles (15, 25, 35, 45 and 55 degrees). The results show that the optimum value of Specific Cutting Energy (SCE) was obtained at blade bevel angle of 23 degrees, oblique angle of 30 degrees and tilt angle of 25 degrees and blade velocity of 3.75 m s(-1).

In this work, the microwave magnetic properties of oblique deposited CoHf/Ta multilayers were investigated. The high frequency magnetic properties of CoHf/Ta multilayers showed different behaviors with oblique angle for different Ta interlayer thickness t. For example, when the Ta interlayer thickness fixed as 5.0 nm, the resonance frequency fr increased from 2.1 to 3.4 GHz with the oblique deposition angle θ changing from 10° to 30°. However, when the Ta layer fixed as 15.0 nm, the fr decreased from 2.5 to 1.7 GHz with the oblique deposition angle changing in the same range. The opposite behavior of the fr with θ is supposed to result from the existence of the Ta buffer layer, in which the thicker Ta interlayer may hinder the self-shadow effects of the CoHf magnetic layers.

3D non-axisymmetric thin-walled tubes can be divided into two categories, the offset and the oblique. The theoretical calculation formulas of the spinning forces for the 3D non-axisymmetric thin-walled tubes based on the slab method are presented. The effects of the rotational angle γ of roller, the offset amount δ of blank per path and the position S of roller revolution plane on the spinning force are analyzed theoretically. It shows that during the 3D non-axisymmetric thin-walled tubes spinning, the spinning forces vary periodically with γ, the variation period is one revolution of roller around workpiece. The maximum and minimum spinning forces occur at the position corresponding to the instantaneous maximum and minimum reductions. The effects of main forming parameters, such as offset amount δ and oblique angle α of blank per path on maximum spinning forces are analyzed experimentally and theoretically. The calculation results conform well to the experiment one. The error is less than 20%. It indicates that the spinning forces for 3D non-axisymmetric thin-walled tubes can be obtained by the slab method.

Within the framework of the transition program of the Deutsche Forschungsgemeinschaft (DFG), the Institute for Aerospace Engineering (ILR) of the Dresden University of Technology (TUD) has investigated instability waves in a laminar boundary layer on a flat plate. Two dimensional Tollmien-Schlichting-Waves (TSW) have been subject of the experiments as well as oblique waves and disturbances emitted by point sources.

The influence of surface corrugation on the growth of Tollmien–Schlichting (TS) waves was examined experimentally in a zero-pressure-gradient boundary layer. Corrugations with various oblique angles were considered to see how the growth of two-dimensional (2D) TS waves was affected by the angle of surface corrugation. The results clearly showed that as the oblique angle increased, the destabilizing effect (which was pronounced for the 2D corrugation) gradually weakened and that when the corrugation direction was normal to the TS wave, the corrugation little influenced the growth of 2D TS wave though the wave underwent a spanwise distortion corresponding to the corrugation.

The loading history for the hypervelocity impact of a long-rod striking a moving flat plate at an oblique angle was analyzed using the EPIC code. The loads were reduced to their axial and lateral components to provide insight into the penetration problem as well as indicate temporal regimes where loading must be considered in the design and analysis of long rod penetrators. Furthermore, the effect of an EPIC input parameter, the erosion strain, used for the numerical treatment of eroding interfaces was assessed with attention focused on the predictions of peak loads, mass loss, and final configuration of the rod.

The air pressures within the glottis during phonation may be highly dependent upon the symmetry of the glottis and other laryngeal structures. Physical laryngeal models M5 and M6 have been used to explore the slanted “oblique” glottis with different included and oblique angles, the change to three dimensions, and the presence of the arytenoid cartilages. Results suggest that (1) the greater the oblique angle, the higher the glottal entrance pressures compared to the symmetric glottis, (2) the larger the intraglottal angle, the more different the pressures are on the two glottal sides, (3) pressures are higher on the convergent side than on the divergent side of the glottis, (4) intraglottal pressure depends on which side of the glottis the flow exits, with the Flow Wall side having lower pressures, (5) for large glottal diameters, all intraglottal pressures may be lower on the Flow Wall side, (6) for special cases of high transglottal pressure, the pressure near glottal exit may be lower than at entrance ...

Wet etching was performed on N polar GaN, which was fabricated by laser lift-off from a sapphire substrate. Dodecagonal pyramids appeared on the N-polar GaN surface after immersion into hot H3PO4 solution even if it had been etched previously with hot KOH solution. According to the symmetry of the space group of C6v4-P6mc, the oblique angle and crystallographic plane indices of the pyramid facets were obtained. It was observed that the oblique angles of the etched facets decreased from the tip to the base of the pyramids. The etching rate was fast when the etching temperature was above 130 °C, and the oblique angle at the base was reduced. The enhancement of light output with increasing etching temperature has been confirmed. The polarization charges on the different facets were assigned to a kinetics-limited process by the special behavior of the hot H3PO4 etching.

An equation for calculating the spinal-cord depth from a simulator radiograph taken at an oblique angle has been derived. This equation is very useful when the cord cannot easily be identified on a horizontal lateral radiograph as in the case of the lower neck and upper thorax. To use this equation one needs to know the following parameters: the source-Axis-Distance, vertical source-skin-distance, the gantry angle at which the film was taken, and the target-film-distance.

Modeling the human larynx can provide insights into the nature of flow within the glottis. This study reports intraglottal pressure profiles and flow visualization for a symmetric and an oblique glottis with a glottal angle of 10 deg divergence. For the oblique case, the glottis slanted at an angle of 15 deg. A Plexiglas model of the larynx was used. Each vocal fold had at least 11 pressure taps. The minimal glottal diameter was held constant at 0.04 cm. Each case was subjected to steady airflow corresponding to transglottal pressure drops of 3, 5, 10, and 15 cm H2O. Pressure profile results showed that pressures were different on the two sides of the glottis; these data were strongly supported by an earlier study using a different model. Flow visualization in all cases showed that flow separated from one side of the glottis and remained attached to the other. For the oblique case, the separation point on the divergent wall moved upstream in the glottis with greater flows. The laminar core of the skewed j...

The soil restraint on pipelines due to oblique relative movement betwen the pipeline and dry loose sand was investigated. Model pipes 1.22 m long with diameters of 38.1, 76.2, 152.4, and 228.6 mm are obliquely moved from vertical to horizontal direction in the drag box to study the soil restraint of the oblique pipes with various relative velocities. All test results indicate that the dimensionless ultimate soil restraints have a power law relationship with the pipe velocity. The velocity exponent increases slightly with the oblique angle and embedded depth of the pipe. Furthermore, the soil restraint also increases with both the pipes oblique angle and embedded depth. Most of the increase in the soil restraint is associated with the oblique angles in the interval between 45 and 90°. The limit equilibrium model succesfully predicted the soil restraint of the pipe. Normailized force–displacement relationships of soil–pipe interaction could be represented by two-constant hyperbolic equation. The findings sh...

The effect of waves on a shore depends largely on the angle of approach, for the energy of the advancing waves tends to erode the headlands and drift the products of erosion into the bays. Wave refraction applies to waves approaching the shore in any direction, but is only ideally developed in ordinary weather conditions or by approaching waves caused by distant storms. Locally developed storm waves usually approach the shore at an oblique angle to its general trend, owing to the failure of wave refraction and are the most effective where locally they meet the shore at right angles. Beach drifting will be in operation along the section of the shore which happens to be at an angle oblique to the direction of the approaching waves.