bluuebunny/crossref_metadata_2025_split huggingface dataset:
TGD5 is required for normal morphogenesis of non‐mesophyll plastids, but not mesophyll chloroplasts, in Arabidopsis
Authors: Itoh Ryuuichi D. , Nakajima Kohdai P. , Sasaki Shun , Ishikawa Hiroki , Kazama Yusuke , Abe Tomoko , Fujiwara Makoto T. 
Published: April 2021

SummaryStromules are dynamic membrane‐bound tubular structures that emanate from plastids. Stromule formation is triggered in response to various stresses and during plant development, suggesting that stromules may have physiological and developmental roles in these processes. Despite the possible biological importance of stromules and their prevalence in green plants, their exact roles and formation mechanisms remain unclear. To explore these issues, we obtained Arabidopsis thaliana mutants with excess stromule formation in the leaf epidermis by microscopy‐based screening. Here, we characterized one of these mutants, stromule biogenesis altered 1 (suba1). suba1 forms plastids with severely altered morphology in a variety of non‐mesophyll tissues, such as leaf epidermis, hypocotyl epidermis, floral tissues, and pollen grains, but apparently normal leaf mesophyll chloroplasts. The suba1 mutation causes impaired chloroplast pigmentation and altered chloroplast ultrastructure in stomatal guard cells, as well as the aberrant accumulation of lipid droplets and their autophagic engulfment by the vacuole. The causal defective gene in suba1 is TRIGALACTOSYLDIACYLGLYCEROL5 (TGD5), which encodes a protein putatively involved in the endoplasmic reticulum (ER)‐to‐plastid lipid trafficking required for the ER pathway of thylakoid lipid assembly. These findings suggest that a non‐mesophyll‐specific mechanism maintains plastid morphology. The distinct mechanisms maintaining plastid morphology in mesophyll versus non‐mesophyll plastids might be attributable, at least in part, to the differential contributions of the plastidial and ER pathways of lipid metabolism between mesophyll and non‐mesophyll plastids.
Membrane concentrate management for textile wastewater with thermally activated persulfate oxidation method
Authors: Yabalak Erdal , Ozay Yasin , Vatanpour Vahid , Dizge Nadir 
Published: April 2021

AbstractIn this study, concentrated textile wastewater using NF270 membrane was further treated by thermally activated persulfate (TAP) oxidation method. First, the effluent of the textile wastewater treatment plant was treated using NF270 membrane, and the concentrated stream was obtained. Second, the TAP method was applied using the central composite design (CCD) optimization method. The steady‐state permeate flux of NF270 was obtained as 3.4, 6.8, 17.4 L/m2.h, respectively, for 10, 15, 20 bars pressure. COD concentration and color in concentrated stream increased from 880 mg/L and 2960 Pt‐Co to 1120 mg/L and 4860 Pt‐Co, respectively, when operating pressure increased from 10 to 20 bars. The results obtained from the CCD optimization method showed that the experimental and predicted values showed a good fit in both chemical oxygen demand (COD) and color removals models. The maximum experimental values of COD and color removal efficiencies were obtained 69% and 95%, respectively, at 370 K temperature, 60 mM K2S2O8 concentration, and 80 min treatment time. The NF270 concentrated stream was also filtrated from the 2nd stage of NF270 membrane after TAP treatment. The results showed that TAP degradation of concentrated stream improved the 2nd stage of NF270 membrane flux compared without degradation. The proposed TAP method was successfully used to further the treatment of textile wastewater concentrated stream for NF270 membrane.
A New Design of a Pinwheel-Shaped High-G Combustor
Authors: Liu Yu , Wang Zishuo , Tang Hao 
Published: April 2021

Abstract
High-g combustor (HGC) is a significant branch of the ultracompact combustor, an innovative gas turbine combustor with the ability to shorten the combustor length and improve engine efficiency. To improve the feasibility of the HGC concept, a new HGC was designed to substitute the conventional combustor of a KJ66 small turbine engine. The KJ66 was modified to fit an instrumentation system and test bench to conduct relative experiments. Based on the experiment results, design iterations were conducted relying on simulation methods. The design iteration was comprised of six primary configurations, of which the first four configurations focused on establishing an appropriate high-centrifugal environment to accelerate primary combustion, while the last two modifications focused on improving overall combustion performance. In configuration 4, a pinwheel-shaped swirl inlet was designed to successfully create the high-g environment and balance the flow distribution while bringing insignificant total pressure loss. One modification of configuration 4 was a grid inlet design that divided the inlet channel into several subchannels to constrain the inlet flow and establish an ideal high-g environment. The other modification was a divergent mainstream channel to encourage the dilution process and improve the exit temperature profile. The final design could save at least 1/3 of combustor length while maintaining the same level of performance as the original combustor. Further, the engine was predicted to save at least 12% of the total engine weight and improve at least 14% of the engine thrust-to-weight ratio.
Toward A Mobile Robot for Vibration Control and Inspection of Power Lines
Authors: Kakou Paul-Camille , Barry Oumar 
Published: April 2021

Abstract
As power demand across communities increases, focus has been given to the maintenance of power lines against harsh environments such as wind-induced vibration (WIV). Inspection robots and fixed vibration absorbers (FVAs) are the current solutions. However, both solutions are currently facing many challenges. Inspection robots are limited by their size and considerable power demand, while FVAs are narrowband and unable to adapt to changing wind characteristics and thus are unable to reposition themselves at the antinodes of the vibrating loop. In view of these shortcomings, we propose a mobile damping robot (MDR) that integrates inspection robots mobility and FVAs WIV vibration control to help maintain power lines. In this effort, we model the conductor and the MDR by using Hamilton’s principle, and we consider the two-way nonlinear interaction between the MDR and the cable. The MDR is driven by a proportional-derivative (PD) controller to the optimal vibration location (antinodes) as the wind characteristics vary. The numerical simulations suggest that the MDR outperforms FVAs for vibration mitigation. Furthermore, the key parameters that influence the performance of the MDR are identified through a parametric study. The findings could setup a platform to design a prototype and experimentally evaluate the performance of the MDR.
Experimental Visualization and Analysis of Multiphase Immiscible Flow in Fractured Micromodels Using Micro-Particle Image Velocimetry
Authors: Haque Najrul , Singh Anugrah , Saha Ujjwal K. 
Published: April 2021

Abstract
The study of fluid flow through fractured porous media has drawn immense interest in the fields of soil hydrology, enhanced oil recovery (EOR), and others. In this work, a low-cost fractured micromodel with regular pore geometry is fabricated and visualization experiments are performed to study the flow field produced by single- and two-phase immiscible flows. The fractured micromodel is fabricated using polydimethylsiloxane (PDMS) substrate. The micro-particle image velocimetry (PIV) method is applied to map the flow velocity, both at the throat and near the fracture region of micromodel. In two-phase flow, imbibition flow experiments are performed to investigate the effects of fracture on the front migration caused by the trapping mechanism of residual fluid (displaced phase). The velocity distribution obtained for the two-phase flow revealed many peculiarities that are completely different from the single-phase flow pattern. These peculiarities create instabilities that yield random preferential flow paths near the pockets of stagnant fluid. Such dynamic events are quantified by mapping the velocity magnitude of flow fields. No effects of fracture are seen in the single-phase flow where uniform flow patterns are observed in the porous region. However, for the two-phase flow, more pockets of trapped fluids are found at the junction of two fractures.
Drilling Data-Based Approach to Build a Continuous Static Elastic Moduli Profile Utilizing Artificial Intelligence Techniques
Authors: Siddig Osama , Alafnan Saad , Elkatatny Salaheldin , Abdulraheem Abdulazeez 
Published: April 2021

Abstract
Young's modulus is a principle geomechanical property that reflects the material stiffness. Good knowledge about rock mechanical properties significantly facilitates fracturing design and in-situ stresses estimation. Conventionally, rock elastic properties are estimated either experimentally or using well log data, known as static and dynamic respectively. Conducting experiments on core samples is costly, time-consuming and does not provide continuous information. While dynamic Young's modulus provides a complete profile, however, it needs the availability of acoustic logs and its estimations differ from the static values. The objective of this paper is to create a continuous profile of Young's modulus using the drilling rig sensors records. The presented approach relies on the fact that the drilling data such as drill pipe torque, weight on bit and rate of penetration are available at an early stage without additional cost. Three machine-learning algorithms were used to correlate the drilling data with Young's modulus: random forest, adaptive neuro-fuzzy inference system and functional network. Two different datasets were used in this study, one construct and test the model, while the other was hidden from the algorithms and used later to validate the built models. The two datasets contain over 3900 data points and cover different types of rocks. Two out of the three methods utilized yielded a remarkable match between the given and predicted values. The correlation coefficients ranged between 0.92 and 0.99 average absolute percentage errors were less than 13%. Supported by these results, the utilization of drilling data and artificial intelligence techniques to predict the elastic moduli is promising. This approach could be investigated for other geomechanical properties, besides, the performance of other machine-learning methods for the same purpose.
Computation of Spatial Displacements From Geometric Features
Authors: Ravani B. , Ge Q. J. 
Published: April 2021

Abstract
This paper develops the theoretical foundation for computations of spatial displacements from the simple geometric features of points, lines, planes and their combinations. Using an oriented projective three space with a Clifford Algebra, all these three features are handled in a similar fashion. Furthermore, issues related to uniqueness of computations and minimal number of required features are discussed. It is shown that contrary to the common intuition, specification of a minimum of four points (planes) or three lines (each pair being non-planar) are necessary for computation of a unique displacement. Only when the sense of the orientations of these features are specified then the minimal number of required features reduces to three for points and planes and two for lines. The results, in addition to their theoretical interest in computational geometry of motion, have application in robot calibration.
Nonlinear Programming Using Logic Methods
Authors: Lu Peng , Siddall James N. 
Published: April 2021

Abstract
The algorithm presented here combines Boolean logic analysis with heuristic search to solve the general 0-1 polynomial programming problem. It can also be extended to solve continuous variable problems, after the problem has been converted to discrete polynomial form. Logic relations embedded in 0-1 variables are explored by a simple consensus operation to serve as the main minimization strategy. The procedure for sequential generation of prime implicants avoids rapidly increasing the number of prime implicants when problems become large. The computational results indicate that this algorithm is quite reliable for 0-1 problem formulations.
A Multi-Expert System for Sheet Metal Part Design
Authors: Wilson William R. D. , Wang Jyhwen 
Published: April 2021

Abstract
A multi-expert system approach for the design of sheet metal parts, and its implementation is described. The system uses a frame-based, object-oriented representation scheme to model the part design as well as the expert knowledge. To facilitate the collaborative design process, a blackboard architecture is used. Heuristic search methods that guide the collaborative design process are presented. The advantages offered by such a multi-expert system are also discussed.
Optimal Design of Resonance Suppression Helical Springs
Authors: Lin Yuji , Hodges P. H. , Pisano A. P. 
Published: April 2021

Abstract
Based on a previously developed and verified helical spring dynamic model, optimization and FFT routines have been added to the spring dynamic model as controlling and postprocessing units to form a computer-based optimal design tool. The objective function minimized is the amplitude of spring resonance. Design variables are the coefficients of a polynomial which describes the variation of the diameter of spring wire along the spring helix. Constraints are the maximum fatigue stress on any location of spring wire, the minimum and maximum wire diameter, and the maximum required spring force. In a case study for an automobile engine valve spring, resonant harmonic power has been reduced by 47%, given the newly designed spring a potential to be used at 8.3% higher engine speed before potential valve toss occurs.
An Object-Oriented Feature-Based CAD/CAPP/CAM Integration Framework
Authors: Wang Ming-Tzong 
Published: April 2021

Abstract
This paper presents an object-oriented feature-based CAD/CAPP/CAM integration framework in a concurrent engineering environment. The framework which is still under development at Yuan-Ze’s automation center is a layered hierarchy based on an object-oriented feature-based part model. The part model serves as a central database for design, process planning, and manufacturing related activities. Feature-based design approach in conjunction with feature recognition approach is incorporated in this integration framework. This dual approach can balance overall computational efficiency and modeling complexity of the interface between design and process planning.
There are three levels at the process planning stage : primary level, secondary level and detailing level. The primary level is concerned with the issues of intermediate shape generation. At the secondary process planning level the intermediate specifications of features and workpieces are determined. The detailing level elaborates on the selection of corresponding facilities and parameters for each manufacturing operation. This manufacturing information is used to drive the downstream CAM activities such as NC part programming, production control and scheduling, operation setup and so forth.
Hybrid Approach to Plant Layout Design Using Constraint-Directed Search and an Optimization Technique
Authors: Fujita Kikuo , Akagi Shinsuke , Hase Hiroaki , Nakatogawa Tetsundo , Takeuchi Makoto 
Published: April 2021

Abstract
A hybrid type approach to plant layout design is presented with a constraint-directed search procedure and a mathematical optimization technique. In layout design, a plant must be arranged to satisfy spatial constraints imposed by its components. In our approach the whole space of a plant building is divided into the finite compartments with a modular size in order to separate the description of the layout into the combinational part and the dimensional part. According to it, the approach consists of two steps. In the first step, a constraint-directed search procedure is applied for fixing the combinational relations among plant components so as to satisfy the spatial layout conditions. In the second step, an optimization technique is applied for determining the actual dimensions of compartments so as to minimize size of a plant building considering size of components. In the optimization, mixed-integer programming and sequential linear programing are combined and the formulation is carried out automatically from the result of the first step. This hybrid approach has been applied to the design of a nuclear power plant in order to check its validity and effectiveness.
Optimization of a Spherical Five Bar Parallel Drive Linkage
Authors: Ouerfelli Mohamed , Kumar Vijay 
Published: April 2021

Abstract
The spherical five bar parallel drive linkage is investigated for use as a spherical manipulator or as a pointing mechanism. The direct and inverse kinematics are derived for a general 5-R linkage. Kinematic and dynamic optimization yields a geometry in which all link lengths are equal to a right angle.
A Counterexample to Signal-to-Noise Ratio As a Measure of Design Robustness
Authors: Wilde Douglass J. 
Published: April 2021

Abstract
Maximizing signal-to-noise ratio generates off-center designs that can be far from robust. To demonstrate this in engineering terms, a counterexample is constructed by relaxing a physically unnecessary constraint in Taguchi’s robust circuit design illustration. In this new case the badly off-center design obtained by maximizing signal-to-noise ratio is not even as robust as the worst of the centered designs. This did not occur in the original example because the artificial constraint, relaxed in the counterexample, fortuitously held the maximum signal-to-noise ratio design near the robust least variation design.
Quantifying Design Feasibility Using Probabilistic Feasibility Analysis
Authors: Eggert R. J. 
Published: April 2021

Abstract
Engineered products are designed for manufacture using nominal values and tolerances. As such, finished products will more or less satisfy design specifications depending on the actual materials and manufacturing processes used. Design feasibility, therefore, depends on how these variations impact specified constraints. Probabilistic feasibility analysis can be used to extend conventional feasibility analysis. By using moment matching and simulation, the probability of points occurring in the design space can be evaluated. The resulting values establish the limits of feasibility and the amount of feasibility in between. The nature of variation in mechanical design is introduced along with concepts of variation propagation in functions of random variables. Moment matching methods are applied to illustrative cases consisting of deterministic and probabilistic constraint equations, resulting in three dimensional feasibility mappings of each design space.
Structural Optimization With Nonlinear Goal Programming Using Powell’s Method
Authors: El-Sayed Mohamed E. M. , Jang T. S. 
Published: April 2021

Abstract
This paper presents a method for solving structural optimization problems using nonlinear goal programming techniques. The developed method removes the difficulty of having to define an objective function and constraints. It also has the capacity of handling rank ordered design objectives or goals. The formulation of the structural optimization problem into a goal programming form is discussed. The resulting optimization problem is solved using Powell’s conjugate direction search algorithm. To demonstrate the effectiveness of the method, as a design tool, the solutions of some numerical test cases are included.
Diapiric relamination of the Orocopia Schist (southwestern U.S.) during low-angle subduction
Authors: Chapman James B. 
Published: April 2021

AbstractThe Orocopia Schist and related schists are sediments subducted during the Laramide orogeny and are thought to have been underplated as a laterally extensive layer at the base of the crust in the southwestern United States Cordillera. This concept is hard to reconcile with the existence of continental mantle lithosphere in southeastern California and western Arizona. Analytical solutions and numerical modeling suggest that the Orocopia Schist may have ascended through the mantle lithosphere as sediment diapirs or subsolidus crustal plumes to become emplaced in the middle to lower crust. Modeled time-temperature cooling paths are consistent with the exhumation history of the Orocopia Schist and explain an initial period of rapid cooling shortly after peak metamorphism. The Orocopia Schist represents a potential example of relaminated sediment observable at the surface.
The spatial and temporal evolution of the Portland and Tualatin forearc basins, Oregon, USA
Authors: Scanlon Darby P. , Bershaw John , Wells Ray E. , Streig Ashley R. 
Published: April 2021

AbstractThe Portland and Tualatin basins are part of the Salish-Puget-Willamette Lowland, a 900-km-long, forearc depression lying between the volcanic arc and the Coast Ranges of the Cascadia convergent margin. Such inland seaways are characteristic of warm, young slab subduction. We analyzed the basins to better understand their evolution and relation to Coast Range history and to provide an improved tectonic framework for the Portland metropolitan area. We model three key horizons in the basins: (1) the top of the Columbia River Basalt Group (CRBG), (2) the bottom of the CRBG, and (3) the top of Eocene basement. Isochore maps constrain basin depocenters during (1) Pleistocene to mid-Miocene time (0–15 Ma), (2) CRBG (15.5–16.5 Ma), and (3) early Miocene to late Eocene (ca. 17–35 Ma) time. Results show that the Portland and Tualatin basins have distinct mid-Miocene to Quaternary depocenters but were one continuous basin from the Eocene until mid-Miocene time. A NW-striking gravity low coincident with the NW-striking, fault-bounded Portland Hills anticline is interpreted as an older graben coincident with observed thickening of CRBG flows and underlying sedimentary rocks. Neogene transpression in the forearc structurally inverted the Sylvan-Oatfield and Portland Hills normal faults as high-angle dextral-reverse faults, separating the Portland and Tualatin basins. An eastward shift of the forearc basin depocenter and ten-fold decrease in accommodation space provide temporal constraints on the emergence of the Coast Range to the west. Clockwise rotation and northward transport of the forearc is deforming the basins and producing local earthquakes beneath the metropolitan area.