Double Projection Research Articles

Proposed single-zone map projection system for Turkey

AbstractThe coordinate base of the maps or sheets produced is the Universal Transversal Mercator (UTM) conformal projection, and it is not possible to work in a single coordinate system in Turkey. Therefore, a transition from UTM to other conformal projections is required. For the countries extending in an east–west UTM zone width like Turkey, composite projection (CP), a double standard paralleling Lambert Conformal Conic (LCC) and double map projections (DP) are used widely. However, this process causes increase in working load and processing errors by users. This study aims to determine a common projection system that can be used in the whole country. In this context, a composite projection from UTM and LCC projection has been defined for the first time. According to the results obtained, map projection CP with the least distortion values in both east–west and north–south directions has been chosen. With the CP selection, a single coordinate system has been determined for medium- and large-scale maps. Projection correction formulas, scale factor and false origin have been determined for map coordinates in CP. These distortions are obtained with a difference of less than 1 cm for 1 km long sides and less than 0.003″ for the azimuth value of this side, when the correction formulas are used.

STUDI PENAMBAHAN STRUKTUR BETON BERTULANG MENJADI KOMPOSIT DENGAN BAJA BERGELOMBANG PADA OVERPASS PUCUNG LOR KROYA

The construction of a nonlevel railway crossing in Pucung Lor Kroya was aimed to improve safety and smooth traffic between railways and roads. Increasing frequency of railways through the Double Track Railway Project of South Java demands a fast pace construction of railway crossing without disrupting any railway traffic. So, the overpass structure will be built using Corrugated Mortar Busa Pusjatan (CMP) technology with Corrugated Steel Plate (CSP) on a curve structure 1 (P1) with a 25-meter span and curve structure 2 (P2) with a 12-meters span. When construction began, planners added reinforced concrete layers until composite with CSP to increase structural capacity and became structural protectors if CSP yielded or corrosions. Overpass modeling was done using MIDAS Civil 2019 based on finite element 3D to check strength capacity and service limits. The addition of reinforced concrete structures to composites with CSP is also compared to the non-composite design of CMP Pusjatan to see the effect on internal forces, stress, and deflection of CSP although the stress on foam mortar. Based on the results, the composite design overpass analysis satisfies compression-bending and shearing capacity checks based on Ultimate Limit States (ULS-PBKT) and service limit based on Serviceability Limit State (SLS-PBL). The addition of reinforced concrete to composite with CSP increases safety factor value because CSP stresses are lower than non-composite designs. The potential collapses from foam mortar can also be reduced as the structure becomes rigid.

ANALYSIS OF FACTORS CAUSING JABODETABEK COMMUTER TRAIN DELAY

The goal to be achieved through this research is to identify the factors that cause delays in the commuter train journey across Bogor-Manggarai Jakarta. The research question is why there is a delay in the journey of the Jakarta Bogor, Depok, Tangerang, Bekasi Commuter Train crossing Bogor-Manggarai. This study uses the Analytic Hierarchy Process to analyze timeliness. With the number of informants taken as many as 12 informants consisting of five people from regulators, five people from operators, one expert in the field of railways and users of commuter train of Jakarta Bogor, Depok, Tangerang, Bekasi. From the measurement results, it was found that the Jakarta, Bogor, Depok, Tangerang, Bekasi Commuter Train was still experiencing delays, due to follow-ups and cross-changes in the operation pattern of the Jakarta Bogor, Depok, Tangerang, Bekasi Commuter Train which was still mixed with long-distance and freight trains, the construction of the Manggarai station as part of the Double Double Track project, the signaling system at the station. Manggarai also underwent changes and there were speed restrictions at Manggarai Station. Recommendations are to complete the construction of the Manggarai and Jatinegara stations which are useful for separating inter-city and urban rail travel, updating the signaling system on the crossing between Bogor Station-Manggarai Station and City Station which is now 30 years old, handling and improving level crossings with coordinate with related units.

Double structured light with divergent projection for surface topometry

A simultaneous double divergent projection of structured light to measure large and complex surfaces at short illumination distances is reported. When the structured and divergent lighting is projected, a moiré pattern is created, with the variable period associated with the out-of-plane surface that is analyzed. A theoretical description of the mathematical model and an algorithm to correct the measurements due to the divergence of the illumination are presented, which aim to establish the correct phase–height relationship. The mathematical model and the proposed method are verified numerically and experimentally. Measurements of the complex surfaces show high accuracy with low uncertainty. The system has been shown to allow rapid measurements in an efficient and easy way using a single camera.

A Framework for Drivable Area Detection Via Point Cloud Double Projection on Rough Roads

A Framework for Drivable Area Detection Via Point Cloud Double Projection on Rough Roads

Synthetic construction of the Hopf fibration in a double orthogonal projection of 4-space

Abstract The Hopf fibration mapping circles on a 3-sphere to points on a 2-sphere is well known to topologists. While the 2-sphere is embedded in 3-space, four-dimensional Euclidean space is needed to visualize the 3-sphere. Visualizing objects in 4-space using computer graphics based on their analytical representations has become popular in recent decades. For purely synthetic constructions, we apply the recently introduced method of visualization of 4-space by its double orthogonal projection onto two mutually perpendicular 3-spaces to investigate the Hopf fibration as a four-dimensional relation without analogy in lower dimensions. In this paper, the method of double orthogonal projection is used for a direct synthetic construction of the fibers of a 3-sphere from the corresponding points on a 2-sphere. The fibers of great circles on the 2-sphere create nested tori visualized in a stereographic projection onto the modeling 3-space. The step-by-step construction is supplemented by dynamic three-dimensional models showing simultaneously the 3-sphere, 2-sphere, and stereographic images of the fibers and mutual interrelations. Each step of the synthetic construction is supported by its analytical representation to highlight connections between the two interpretations.

Feasibility study of CP violation in decays at the Super Tau Charm Facility * *Supported by the Double First-Class university project foundation of USTC, USTC Research Funds of the Double First-Class Initiative YD2030002005 and the National Natural Science Foundation of China (11625523). The author XWK is supported by the National Natural Science Foundation of China (11805012) and the Fundamental Research

We report a feasibility study for violation in decays at a Super Tau Charm Facility (STCF). With an expected luminosity of 1 ab collected by STCF per year at a center-of-mass energy of 4.26 GeV, the statistical sensitivity for CP violation is determined to be of order by measuring the decay-rate difference between and . The analysis is performed using a reliable fast simulation software package, which can describe the detector responses properly and vary the responses flexibly for further optimization. Moreover, the energy-dependent efficiencies for reconstructing are presented. The expected CP sensitivity is proportional to in the energy region from 4.0 to 5.0 GeV. The sensitivity of CP violation is of order with 10 ab integrated luminosity, which is equivalent to ten years' data taking in this energy region at STCF.

The trochanteric double contour is a valuable landmark for assessing femoral offset underestimation on standard radiographs: a retrospective study

BackgroundInaccurate projection on standard pelvic radiographs leads to the underestimation of femoral offset—a critical determinant of postoperative hip function—during total hip arthroplasty (THA) templating. We noted that the posteromedial facet of the greater trochanter and piriformis fossa form a double contour on radiographs, which may be valuable in determining the risk of underestimating femoral offset. We evaluate whether projection errors can be predicted based on the double contour width.MethodsPlain anteroposterior (AP) pelvic radiographs and magnetic resonance images (MRIs) of 64 adult hips were evaluated retrospectively. Apparent femoral offset, apparent femoral head diameter and double contour widths were evaluated from the radiographs. X-ray projection errors were estimated by comparison to the true neck length measured on MRIs after calibration to the femoral heads. Multivariate analysis with backward elimination was used to detect associations between the double contour width and radiographic projection errors. Femoral offset underestimation below 10% was considered acceptable for templating.ResultsThe narrowest width of the double line between the femoral neck and piriformis fossa is significantly associated with projection error. When double line widths exceed 5 mm, the risk of projection error greater than 10% is significantly increased compared to narrower double lines, and the acceptability rate for templating drops below 80% (p = 0.02).ConclusionThe double contour width is a potential landmark for excluding pelvic AP radiographs unsuitable for THA templating due to inaccurate femoral rotation.

Generator coordinate method with a conjugate momentum: Application to particle number projection

We discuss an extension of the generator coordinate method (GCM) by taking simultaneously a collective coordinate and its conjugate momentum as generator coordinates. To this end, we follow the idea of the dynamical GCM (DGCM) proposed by Goeke and Reinhard. We first show that the DGCM method can be regarded as an extension of the double projection method for the center of mass motion. As an application of DGCM, we then investigate the particle number projection, for which we not only carry out an integral over the gauge angle as in the usual particle number projection but also take a linear superposition of BCS states which have different mean particle numbers. We show that the ground state energy is significantly lowered by such effect, especially for magic nuclei for which the pairing gap is zero in the BCS approximation. This suggests that the present method makes a good alternative to the variation after projection (VAP) method, as the method is much simpler than the VAP.

Policy decoupling in strategic response to the double world-class project: evidence from elite universities in China

Creating world-class universities (WCUs) has recently become a significant policy and practice in higher education in China under the Double World-Class Project. However, some negative effects have encouraged decoupling from the policy goals. To identify the reasons, we conducted policy document analysis and purposive interviews at three elite universities, focusing on financial funding, discipline development, and human resources. First, the uneven funding plans by central and local governments shape non-competitive environments for universities, hindering the dynamic adjustment of the Double World-Class Project. Second, universities have closed or merged programs in weak academic disciplines to gain legitimacy and stability in conformance to WCU guidelines. Last, as a result of the unbalanced development of universities in east, middle, and west China, universities in the west are facing a serious brain drain. To achieve a higher level of performance, an increasing number of ‘shadow academics’ are being recruited by Chinese universities. These decoupling responses and manipulative strategies result from the dominating constituent in WCUs, ambiguity in policy contents, hierarchical control systems in higher education, and uncertain environments for universities.

A new measure of thermal micro-behavior for the AdS black hole * *The financial supports from National Natural Science Foundation of China (11947208, 11947301), China Postdoctoral Science Foundation (2020M673460), Major Basic Research Program of Natural Science of Shaanxi Province (2017KCT-12), Scientific Research Program Funded by Shaanxi Provincial Science and Technology Department (2019JQ-081) are gratefully acknowledged. This research is also particularly

Inspired by the hypothesis of the black hole molecule, with the help of the Hawking temperature, entropy, and the thermodynamic curvature of black holes, we propose a new measure of the relation between the interaction and the thermal motion of molecules of the AdS black hole as a preliminary and coarse-grained description. The proposed measure introduces a dimensionless ratio to characterize this relation and shows that there is indeed competition between the interactions of black hole molecules and their thermal motion. For a charged AdS black hole, below the critical dimensionless pressure, there are three transitions between the interaction and thermal motion states. In contrast, above the critical dimensionless pressure, only one transition takes place. For the Schwarzschild-AdS and five-dimensional Gauss-Bonnet AdS black holes, a transition always occurs between the interaction and thermal motion states.

Version 2.0 of Building World-Class Universities in China: Initial Outcomes and Problems of the Double World-Class Project

Version 2.0 of Building World-Class Universities in China: Initial Outcomes and Problems of the Double World-Class Project

A new class of three-term double projection approach for solving nonlinear monotone equations

The derivative-free projection methodology is important and highly efficient method to solve large scale monotone equations of nonlinear systems. In this work, we suggested a new class of extensions projection approach employs along with a new line search to show a class of new double projection technique for solving monotone systems of nonlinear equations. Our algorithm can be applied to solve nonsmooth equations, furthermore it’s suitable for large scale equations due to simplicity and limited memory. This method constricts new two appropriate hyperplanes in each point strictly separates xk from the solution set, it can obtain the next iteration x k+1 by projecting xk onto the intersection of two halfspaces and include the solution set of the problem. The global convergence of the given method is investigated with mild assumptions. The numerical experiments prove that the new approach is working well and so promising.

Low-complexity soft-output signal detector for massive MIMO with higher order QAM constellations

As the number of base station (BS) antennas in massive multiple-input multiple-output (MIMO) systems is dramatically increased, linear detection methods are able to achieve the near optimal performance at the expense of performing the complicated matrix inversion of a high dimensional matrix, which makes hardware implementation infeasible. Meanwhile, the straightforward application of the hard symbol-to-bit decision algorithm yields a very poor performance for the higher order quadrature amplitude modulation (QAM) that is widely adopted as an efficient tool to accommodate high demand of data throughput in modern wireless systems. In this work, we propose a low-complexity soft-output signal detector for multiuser massive MIMO communication systems employing Gray-coded higher order QAM with square constellations. In the proposed detector, the two-dimensional double successive projection (2D-DSP) algorithm is utilized to iteratively realize zero-forcing (ZF) algorithm for multiuser signal recovery, which circumvents the matrix inverse operation. Moreover, a simplified implementation of Max-Log-MAP algorithm is developed to calculate log likelihood ratios (LLRs) for soft-input channel decoding by fully exploiting the bit-flipping property of Gray-coded modulation scheme along with the utilization of the channel hardening property of the massive MIMO systems. Numerical results show that the proposed soft-output detector provides a relatively good tradeoff between the complexity and performance compared with several existing detectors, and approaches the performance of the ZF algorithm with only 3 iterations.

Cosmogenic Activation in Double Beta Decay Experiments

Double beta decay is a very rare nuclear process and, therefore, experiments intended to detect it must be operated deep underground and in ultra-low background conditions. Long-lived radioisotopes produced by the previous exposure of materials to cosmic rays on the Earth’s surface or even underground can become problematic for the required sensitivity. Here, the studies developed to quantify and reduce the activation yields in detectors and materials used in the set-up of these experiments will be reviewed, considering target materials like germanium, tellurium and xenon together with other ones commonly used like copper, lead, stainless steel or argon. Calculations following very different approaches and measurements from irradiation experiments using beams or directly cosmic rays will be considered for relevant radioisotopes. The effect of cosmogenic activation in present and future double beta decay projects based on different types of detectors will be analyzed too.

A double mask projection exposure method for stereolithography

Mask Projection Stereolithography (MPSL) is an additive manufacturing technology that allows direct fabrication of complex parts from liquid resin. However, the present MPSL systems cannot meet the requirements of high accuracy and large building envelope at the same time. In order to solve this problem, a Double Mask Projection Stereolithography (DMPSL) system combining two projection modules is proposed based on Digital Micromirror Device. The Large Envelope Projection (LEP) module with a building envelope of 55 mm × 41 mm offers a pixel size of 53.8 μm to achieve large building space. In order to improve the local feature accuracy, the high accuracy features are fabricated by the High Accuracy Projection (HAP) module with a building envelope of 6.8 mm × 5.1 mm, offering a pixel size of 6.6 μm. The calibration and alignment of the system were implemented. The samples for shape and dimension accuracy tests were fabricated by DMPSL, respectively. The results indicated that the shape and dimension accuracy of the features requiring high accuracy was significantly improved. In addition, to overcome the poor mechanical properties at the splicing interface, the effects of splicing shape and overlapping width on the mechanical properties were studied. It was found that the poor mechanical properties can be improved by using straight line splicing strategy with overlapping width of 10 or 20 pixels, which makes DMPSL useful for producing parts that can be directly used in stress environments.

Topology Optimization for FDM Parts Considering the Hybrid Deposition Path Pattern.

Based on a solid orthotropic material with penalization (SOMP) and a double smoothing and projection (DSP) approach, this work proposes a methodology to find an optimal structure design which takes the hybrid deposition path (HDP) pattern and the anisotropic material properties into consideration. The optimized structure consists of a boundary layer and a substrate. The substrate domain is assumed to be filled with unidirectional zig-zag deposition paths and customized infill patterns, while the boundary is made by the contour offset deposition paths. This HDP is the most commonly employed path pattern for the fused deposition modeling (FDM) process. A critical derivative of the sensitivity analysis is presented in this paper, which ensures the optimality of the final design solutions. The effectiveness of the proposed method is validated through several 2D numerical examples.

Double graphs-based discriminant projections for dimensionality reduction

Graph embedding plays an important role in dimensionality reduction for processing the high-dimensional data. In graph embedding, its keys are the different kinds of graph constructions that determine the performance of dimensionality reduction. Inspired by this fact, in this article we propose a novel graph embedding method named the double graphs-based discriminant projections (DGDP) by integrating two designed discriminative global graph constructions. The proposed DGDP can well discover the discriminant and geometrical structures of the high-dimensional data through the informative graph constructions. In two global graph constructions, we consider the geometrical distribution of each point on each edge of the graphs to define the adjacent weights with class information. Moreover, in the weight definition of one graph construction, we further strengthen pattern discrimination among all the classes to design the weights of the corresponding adjacent graph. To demonstrate the effectiveness of the proposed DGDP, we experimentally compare it with the state-of-the-art graph embedding methods on several data sets. The experimental results show that the proposed graph embedding method outperforms the competing methods with more power of data representation and pattern discrimination in the embedded subspace.

Specification Tests for Generalized Propensity Scores Using Double Projections

This paper proposes a new class of nonparametric tests for the correct specification of generalized propensity score models. The test procedure is based on two different projection arguments, which lead to test statistics with several appealing properties. They accommodate high-dimensional covariates; are asymptotically invariant to the estimation method used to estimate the nuisance parameters and do not requite estimators to be root-n asymptotically linear; are fully data-driven and do not require tuning parameters, can be written in closed-form, facilitating the implementation of an easy-to-use multiplier bootstrap procedure. We show that our proposed tests are able to detect a broad class of local alternatives converging to the null at the parametric rate. Monte Carlo simulation studies indicate that our double projected tests have much higher power than other tests available in the literature, highlighting their practical appeal.

A new low-cost double projection method for solving variational inequalities

In this work we are concerned with variational inequalities in real Hilbert spaces and introduce a new double projection method for solving it. The algorithm is motivated by the Korpelevich extragradient method, the subgradient extragradient method of Gibali et al. and Popov’s method. The proposed scheme combines some of the advantages of the methods mentioned above, first it requires only one orthogonal projection onto the feasible set of the problem while the next computation has a closed formula. Second, only one mapping evaluation is required per each iteration and there is also a usage of an adaptive step size rule that avoids the need to know the Lipschitz constant of the associated mapping. We present two convergence theorems of the proposed method, weak convergence result which requires pseudomonotonicity, Lipschitz and sequentially weakly continuity of the associated mapping and strong convergence theorem with rate of convergence which requires Lipschitz continuity and strongly pseudomonotone only. Primary numerical experiments and comparisons demonstrate the advantages and potential applicability of the new scheme.