Convex Portions Research Articles

A nonparametric least squares regression method for forecasting building energy performance

The Convex Nonparametric Least Squares (CNLS) method assumes that the regression function is either concave or convex to forecast building energy performance. However, there may be instances where the regression function exhibits both concave and convex patterns, rendering this assumption invalid. This paper aims to address this drawback and to derive a new method called Monotone Nonparametric Least Squares (MNLS), which incorporates both concavity and convexity constraints in CNLS. It is proved that MNLS has a better goodness-of-fit performance compared to CNLS. Since MNLS contains both concave and convex portions, it is not sufficient to rely solely on the concavity assumption (or convexity assumption) during the forecasting process of building energy performance. To tackle this issue, using both concave and convex portions separately and then combining the resulting forecasts is suggested. An illustrative example is provided, and the energy performance of Hong Kong secondary schools is used as an application to demonstrate the goodness-of-fit of MNLS.

Tectono-geomorphic and active deformation studies in the Ujh basin of Northwestern Himalaya

This study focuses on the morphotectonic analysis of the Ujh River basin, examining various aspects related to geometrical changes in the drainage basin caused by tectonic and erosional processes. The topographic development of the Ujh River basin is a response to enhanced tectonic deformation caused by Main Central Thrust (MCT) and Main Boundary Thrust (MBT). We assume that the basin asymmetry, tilting, incision, and migration of the river basin are regulated by the compressive force generated between MBT and MCT. The results were characterized by a high Asymmetry Factor (Af) indicating greater asymmetry suggesting a rightward tilting with low Valley Floor to Valley Width (Vf) values which indicate differential uplift and incision owing to ongoing tectonic processes. The high Stream Length Gradient (SL) Index values in the MCT zone, indicate sudden topographic breaks caused by the vertical tectonic uplift with active erosion processes. The Ujh River basin is in a disequilibrium state, with convex portions indicating uplift and concave portions indicating subsidence on the slope-area plot. The χ analysis, plotting χ values against elevation, highlights upliftment and erosion zones along the trunk stream, with major slope breaks and high χ values observed in the upstream region, particularly along the MCT. Overall, the Ujh River basin exhibits morphotectonic characteristics indicating ongoing tectonic activity and a state of disequilibrium.

Investigation of shear droop formation around convex portions of blanked components

A large shear droop generated in the convex portions of blanked components leads to functional problems, such as a decrease in the effective thickness of gear parts. In this study, the cause of this issue was investigated by comparing half-blanked workpieces with circular and rhombic profiles. The large shear droop at the convex tip was closely related to the tip radius, specifically the indented deformation occurring at the convex tip. The experimental results were verified by the finite element method, and the numerical results agreed closely with the experimental ones. The cause of the increase in shear droop at the convex tip was quantitatively explained using a deformation model and corresponding stress distributions.

Cut Surface Features in Various Die-Cutting Processes

Currently, the shaped parts combined with straight, concave, and convex portions are increasingly fabricated. To produce the straight portion, the shearing theory is usually applied. As well as, to produce the concave and convex portions, the punching and blanking theories are usually applied. However, with the same die-cutting process parameters, the comparison of cut surface features of straight, concave, and convex portions has not been investigated yet. Therefore, in the present research, the comparison of the cut surface features in various die-cutting processes, including shearing, blanking, and punching processes are investigated. The finite element method (FEM) was used as a tool to investigate these cut surface features. The cut surface features were investigated and clearly identified via the changes of the stress distribution analyses. The results elucidated that with the same die-cutting process parameters, the different cut surface features were obtained. Specifically, the crack formations were easily generated in the case of blanking process, following by the shearing and punching processes, respectively. Therefore, the smooth cut surface was smallest in the case of blanking process, following by the shearing and punching processes, respectively. The laboratory experiments were carried out to verify the accuracy of the FEM simulation results. Based on the cut surface features, the FEM simulation results showed good agreement with the experimental results in terms of the cut surface features. Therefore, to design the die-cutting process parameters to meet the product requirements of complicated shapes, the understanding on these working process parameters being upon the shaped parts is necessarily.

Heuristic Method for Identifying Concave Pareto Frontiers in Multi-Objective Dynamic Programming Problems

Aerospace engineers and analysts tasked with informing system-level decisions commonly seek to identify the frontier of Pareto-optimal solutions with respect to objectives of interest. For problems in which decisions are made over multiple stages or periods, dynamic programming can be an efficient and effective method for identifying such a Pareto frontier. To employ traditional dynamic programming, however, a single objective function must be defined. Aggregation of multiple objectives into a single objective using traditional simple additive weighting has the limitation of permitting identification of only points on convex portions of the Pareto frontier. This can translate into detection of a frontier with significant and misleading gaps. This paper proposes a theory-motivated aggregation function modification and method to improve the ability of dynamic programming procedures to detect concave portions of Pareto frontiers in multi-objective, multistage problems. Following a theoretical motivation and method definition, a military aircraft route planning example is provided to illustrate the method’s accuracy and efficiency.

Deformation Characteristic of Thin Stainless Gasket Material

Previous studies on corrugated metal gaskets have established that the contact width, contact stress, and surface roughness are important design parameters for optimizing gasket performance. However, the metal gaskets studied previously required a high axial force for the tightening process; in addition that metal gaskets tend to corrode easily. In this study, we examined the deformation mode of a thin stainless gasket using a finite element method (FEM) analysis. A final evaluation was made using a compression examination. The analysis based on the dimension of flat and convex portion. The load, deformation mode, and contact stress were obtained through a simulation. Based on the deformation of the flat and convex portions, the deformation modes were divided into three types. The deformation mode of the thin stainless gasket material has a higher probability of deformation in mode I when the aspect ratio of the length of the flat portion to the length of the convex portion, L/D, increases.

Management of the malignant colorectal polyp: ACPGBI position statement

*Royal Wolverhampton Hospitals NHS Trust, Wolverhampton, UK, †Torbay Hospital, Torquay, UK, ‡Department of General Surgery, Manchester Royal Infirmary, Manchester, UK, §Royal Infirmary, Glasgow, UK, ¶Department of Histopathology, Royal Bolton NHS Foundation Trust, Bolton, UK, **Imperial College Healthcare NHS Trust, Charing Cross Hospital, London, UK, ††The Royal Marsden Hospital, London, UK, ‡‡Salisbury NHS Foundation Trust, Salisbury, UK and §§Department of Histopathology, University Hospital of South Manchester, Manchester, UK

Formation of graphene quantum dots by “Planting” hydrogen atoms at a graphene nanoribbon

Different technological approaches for creating graphene quantum dots by the adsorption of hydrogen atoms are considered. The adsorption can occur both at convex portions of a distorted graphene nanoribbon and in the structure formed by two distorted graphene nanoribbon rows superimposed on each other at the places free from the ribbon crossings. It is shown that settlement of hydrogen atoms at convex portions of the nanoribbons is energetically favorable. This gives rise to the creation of insulating graphane (CH) nanodomains separating the conducting regions. As a result, a graphene quantum dot appears. The variation of the electron spectra of graphene quantum dots with the length of these graphane regions is discussed.

A Study of the Optical Properties of Cosmetics Measured by Polarized Light Goniophotometry

Polymethylmethacrylate powders are commonly used to improve the spreadability and blurring effects of powder foundation cosmetics. In this study, the opacity and haze effect of four types of polymethylmethacrylate powders and their 10wt% powder foundation formulation was evaluated. The distorted random hemispherical particulates with both concave and convex portions showed the highest haze and opacity value as a single powder substance. And as a formulated phase, the powder foundation formulation containing particulates with fine pores provided the highest haze and opacity value. We also examined the quantity of reflected light over the angular range 20-75° by polarized light goniophotometry. The total reflected light intensity, surface-reflected light, and internally reflected light were characterized. These studies demonstrated that hemispherical PMMA powders produce natural brilliance by creating high internally reflected light which is similar to the total reflection profile of artificial skin.

Optimal convex shapes for concave functionals

Motivated by a long-standing conjecture of Polya and Szego about the Newtonian capacity of convex bodies, we discuss the role of concavity inequalities in shape optimization, and we provide several counterexamples to the Blaschke-concavity of variational functionals, including capacity. We then introduce a new algebraic structure on convex bodies, which allows to obtain global concavity and indecomposability results, and we discuss their application to isoperimetriclike inequalities. As a byproduct of this approach we also obtain a quantitative version of the Kneser-Suss inequality. Finally, for a large class of functionals involving Dirichlet energies and the surface measure, we perform a local analysis of strictly convex portions of the boundary via second order shape derivatives. This allows in particular to exclude the presence of smooth regions with positive Gauss curvature in an optimal shape for Polya-Szego problem.

Edge Extraction using Image and Three-Axis Tactile Data

Abstract This paper describes a hand-arm system equipped with optical three-axis tactile sensors and a binocular vision sensor. The vision compensates for the limitations of tactile information and tactile sensing, and vice versa. The tactile sensor can obtain geometrical data as real scale, while image data requires calibration to obtain length as a metric unit. Even if stereovision is used, we cannot obtain sufficient precision. In the evaluation test, the robotic hand equipped with tactile sensors traces an object including convex and concave portions to evaluate edge trace precision. Error of distance obtained by the binocular vision is around ± 10 mm when distance between the camera and object is around 600 mm. When the hand-arm robot touches the convex portion of the object, size data obtained by the vision is modified within ± 0.5 mm accuracy. Since the robotic finger is too thick to touch the bottom of the concave, size data of the concave portion obtained by tactile sensing includes relatively large error of around 4 mm. However, the robot finger can follow the contour with ± 0.5 mm accuracy except for the bottom portion. Therefore, vision sensing is not sufficient for precise edge exploration and modification based on tactile sensing is required.

Ploufolia cerciforme gen. et comb. nov.: Aquatic angiosperm leaves from the Upper Albian of north-eastern Spain

An aquatic angiosperm, Ploufolia cerciforme gen. et comb. nov., is reported from the Upper Albian of the Utrillas Formation at the Plou locality, Teruel Province, north-eastern Spain. Ploufolia cerciforme shows eccentric peltate attachment, elliptic to obovate nanophylls, one medial primary vein and lateral veins that dichotomize several times before merging into an intramarginal vein, which links small glands that occur on the convex portions of the marginal undulations. Ploufolia cerciforme shows most affinities with extant Nymphaeales and both sedimentological and taphonomic evidence supports a freshwater lacustrine habit for P. cerciforme. The presence of marginal glands in leaves of P. cerciforme is related to a leaf guttation mechanism, as occurs in plants living in water saturated habitats. By the Albian, aquatic angiosperms were already well diversified and often dominant in western European wetland environments.

Bubble generation and transport in a microfluidic device with high aspect ratio

Bubble generation and transport in a micro-device composed of a micro-T-junction and a following serpentine micro-channel was experimentally investigated. It has a rectangular cross-sectional with an aspect ratio of 7.425. Air and water were used as gas and liquid, respectively. Mixtures of water–glycerol and water–Tween-20 were used to study the effects of liquid viscosity and surface tension. Compared with previous T-junction bubble generation, the liquid and gas inlets orientation was switched in this work. The continuous flow was driven from the perpendicular channel and the dispersion flow was from the main channel. It shows that the break-up process has three periodic steps under certain operating conditions. The dimensionless bubble length L/ w in the micro-channel with high aspect ratio is much larger than that in square microchannels. A correlation is proposed to correlate L/ w with liquid flow rate J L , gas flow rate J G , and liquid viscosity μ L . Surface tension σ can change the bubble shape but almost does not affect the bubble length in this fast break-up process. Additionally, a long bubble may be broken up at the corners at the same time because the locations of gas and liquid are exchanged relative to the concave and convex portions of an elbow after a turn which may result in the change of fluid velocities and gas–liquid pressure drop.

Surface Acoustic Wave Duplexer Composed of SiO2/Cu Electrode/LiNbO3 Structure Having Convex and Concave Portions

The transition bandwidth of 20 MHz between the transmission (Tx: 1850–1910 MHz) and the receiving (Rx: 1930–1990 MHz) bands of personal communication service (PCS) handy phones in the United States (US) is very narrow compared with those of other systems. We have already realized surface acoustic wave (SAW) duplexers with sizes of 5.0×5.0×1.7 and 3.0×2.5×1.2 mm3 for PCS handy phones in the US with an excellent temperature coefficient of frequency (TCF) by using a shear horizontal (SH) wave on a flattened SiO2/Cu electrode/36–48° YX-LiTaO3 structure and a Rayleigh wave on a SiO2/Cu electrode/120–128° YX-LiNbO3 structure. Although the surface of the above-mentioned structures is flattened SiO2, we have also studied the shape of the SiO2 surface. As a result, in addition to increasing the stop-band width, which corresponds to the reflection coefficient, the TCF and power durability have been improved by forming convex portions on the surface of the SiO2 over the interdigital transducer (IDT) gaps.

1J5-1 Surface Acoustic Wave Duplexer Composed of SiO_2/Cu-electrode/LiNbO_3 Structure having convex and concave portions(Bulk wave devices/Surface wave devices)

1J5-1 Surface Acoustic Wave Duplexer Composed of SiO_2/Cu-electrode/LiNbO_3 Structure having convex and concave portions(Bulk wave devices/Surface wave devices)

Do river profiles record along‐stream variations of low uplift rate?

Spatial variations of gradients in landscapes may be used to identify and quantify recent deformation. The problem with doing this is to determine whether tectonic or climatic forcing is responsible for these variations, especially for low uplift rate environments (≪1 mm yr−1) where climate changes may have erased tectonic features. We evaluate the respective contribution of low uplift rate (∼0.1 mm yr−1) and Pleistocene climate oscillations on gradient variations of two comparable river profiles crossing different uplift zones in the southern Upper Rhine Graben. We compare the observed points of discontinuity in river profile (knickpoints) and convex portions (knickzones) with those predicted by a detachment‐limited model that includes stochastic short‐term and cyclic long‐term variations in climate, a bedrock detachment threshold and rock uplift. The detachment‐limited model is chosen as it predicts the development of persistent knickpoints. Differing values of the shear stress exponent, erosion threshold, climate variability and uplift pattern have been checked. Our modeling suggests that climate changes had no significant effects on profiles and that anomalies are more likely due to anticline growth. This surprising result arises from the combination of a very low regional uplift rate and the detachment‐limited assumption. The detachment‐limited model implies an upstream propagation of knickpoints and knickzones generated by uplift at the outlet during dry climate periods of low erosion. The greater the uplift rate, the larger the variations in river bed elevation. Thus, for high uplift rate, knickpoints and knickzones generated by climate oscillations are more likely to hide tectonic features. This result seems counterintuitive because it suggests that tectonic knickzones will be better preserved in low uplift rate environments, provided that the lithology is homogeneous.

The design of varying-velocity translating cam mechanisms

Abstract A translating cam driven by an offset slider–crank mechanism has varying velocity, and the follower motion can be arbitrarily chosen for only the forward or the return stroke of the translating cam. By employing the concept of velocity instant center, the cam profile, the path of cutter, the pressure angle and the radius of curvature of the cam can be expressed parametrically, and the follower motion of the remaining stroke can be analyzed analytically. The cam profile has concave, convex and flat portions.

SiO2/Grooved Al Electrode/LiTaO3 and Edge-Reflection Surface Acoustic Wave Structures Having Large Reflection Coefficient, Large Coupling Factor, and Excellent Temperature Characteristic Even If Al Electrodes Are Used

A surface acoustic wave (SAW) substrate for a duplexer, such as a Personal Communication Service handy phone system in the U.S.A, is required to have a good temperature stability, an optimum electromechanical coupling factor, and a large reflection coefficient. The conventional method of depositing a SiO2 film on a thick Al electrode/LiTaO3 substrate to improve its temperature coefficient of frequency (TCF) is not effective for SAW resonator-type devices, because good frequency characteristics are not obtained due to large convex portions on the surface of SiO2 film. However, resonators having a large reflection coefficient, an excellent TCF, and good frequency characteristics were realized using the following two new structures: (I) SiO2 film/grooved Al electrode/LiTaO3 structure and (II) reflection of a shear horizontal (SH) wave at free edges on a SiO2 film/thin Al electrode/LiTaO3 structure substrate.

Piezoelectric motor and electronic equipment with piezoelectric motor

By obtaining a support structure capable of performing a stable support by means of a simple constitution and without suppressing vibration of a vibrating body, there are aimed at improvements in positioning precision and positioning controllability and a positioning stability, thereby providing a piezoelectric motor whose dispersion of performance is made small. In a piezoelectric motor operating, by vibration of a vibrating body having a piezoelectric element, a contact member contacting with the vibrating body or a friction member provided in the vibrating member or the vibrating body itself, there are possessed plural concave portions provided in the vibrating body, and a support member having plural convex portions engaging with the concave portions.

Molecular changes occurring with aneurysm formation: Possible impact of sampling error

Molecular changes occurring with aneurysm formation: Possible impact of sampling error