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Under the conditions of giving the length of the rocker CD,swinging angle φ and advance-to return-time ratio K（extreme position angle θ）,in order to design crank-rocker mechanism with the maximum value of minimum transmission angle γmin,the supplementary angle β（be used to determine the position angle of the rotation center A of crank） is introduced,the function relation of minimum transmission angle γminand the supplementary angle β is established.Then the maximum value of minimum transmission angle γmincan be obtained by utilizing procedure of Matlab.At the same time,in view of the different K value,the mechanism of type selection is classified.Then,points out the typeⅠ and Ⅱmechanism can be used to design and typeⅠ mechanism is better in force-passing property when K ∈（1,3）.When K∈[3,+ ∞),if type Ⅱ mechanism is used to carry on the design,which will not be able to meet the requirement of the rocker swinging angle,if typeⅠ mechanism is used,which has low efficiency and is not conductive to transmission of the mechanism.

The gear- parallelogram mechanism（ GPM） is a kind of geared linkage combinative mechanism with special motion performance. The composition rules of GPM are introduced,and the transmission property of outer teething type and idle gear type of GPM are analyzed. Meanwhile,according to the principle of the variation of the isomorphism,the evolution and mutation of internal teething type is studied. By the comparison of internal and external meshing combined mechanism,the method of changing different mechanism transmission ratio is summarized and the type of internal teething and internal parallel motion of GPM is chosen,which has large transmission ratio,high mechanical efficiency,small size,light weight,compact structure and better smoothness of moving. Some theoretical basis for design new combined mechanism about reducer and speed increaser is provided.

Quantitative information about test score reliability can be presented in terms of the distribution of equated scores on an alternate form of the test for test takers with a given score on the form taken. In this paper, we describe a procedure for estimating that distribution, for any specified score on the test form taken, by estimating the joint distribution of equated scores on two forms of the test. The procedure requires as input the score distribution and the reliability coefficient, estimated for the test-taker population. In tryouts, the procedure performed well for score distributions like those commonly encountered in large-scale testing situations.

International large-scale assessments (ILSAs) transitioned from paper-based assessments to computer-based assessments (CBAs) facilitating the use of new item types and more effective data collection tools. This allows implementation of more complex test designs and to collect process and response time (RT) data. These new data types can be used to improve data quality and the accuracy of test scores obtained through latent regression (population) models. However, the move to a CBA also poses challenges for comparability and trend measurement, one of the major goals in ISLAs. We provide an overview of current methods used in ILSAs to examine and assure the comparability of data across different assessment modes and methods that improve the accuracy of test scores by making use of new data types provided by a CBA.

One major issue with large-scale assessments is that the respondents might give no responses to many items, resulting in less accurate estimations of both assessed abilities and item parameters. This report studies how the types of items affect the item-level nonresponse rates and how different methods of treating item-level nonresponses have an effect on item calibration and scoring.

In the framework of the observed-score equating methods for the nonequivalent groups with anchor test design, there are 3 fundamentally different ways of using the information provided by the anchor scores to equate the scores of a new form to those of an old form. One method uses the anchor scores as a conditioning variable, such as the Tucker method and poststratification equating. A second way to use the anchor scores is as the middle link in a chain of linking relationships, such as chain linear equating and chain equating. The third way to use the anchor scores is in conjunction with the classical test theory, such as Levine observed-score equating and the newly created hybrid Levine equipercentile equating and poststratification equating based on true anchor scores. The purpose of this paper is to demonstrate that with real data, under certain conditions, hybrid Levine equipercentile equating and poststratification equating based on true anchor scores outperform both poststratification equating and chain equating.

As a renewable resource, geothermal energy plays an increasingly important role in global and regional energy structures. Influenced by regional tectonic activities, multi-stage thermal evolution, and continuous subsidence, the subsurface temperatures in the Yinggehai Basin has been consistently rising, resulting in the formation of multiple geothermal reservoirs. The Neogene Huangliu Formation, with its high geothermal gradients, suitable burial depths, considerable thickness, and wide distribution, provides excellent geological conditions for substantial geothermal resources. However, the thermal storage characteristics and geothermal resources of this formation have not been fully assessed, limiting their effective development. This study systematically collected and analyzed drilling, geological, and geophysical data to examine these reservoirs' geometric structures, thermal properties, and physical characteristics. Further, we quantitatively evaluated the geothermal resource potential of the Huangliu Formation and its respective reservoirs through volumetric estimation and Monte Carlo simulations, pointing zones with high geothermal prospects and formulating targeted development strategies. The findings indicate: (1) The Yinggehai Basin exhibits an average geothermal gradient of 39.4 ± 4.7 °C/km and an average terrestrial heat flow of 77.4 ± 19.1 mW/m2, demonstrating a favorable geothermal background; (2) The central depression of the Huangliu Formation harbors considerable geothermal resource potential, with an average reservoir temperature of 140.9 °C, and a total geothermal resource quantified at approximately 2.75 × 1020 J, equivalent to 93.95 × 108 tec. Monte Carlo projections estimate the maximum potential resource at about 3.10 × 1020 J, approximately 105.9 ×108 tec. (3) Additionally, the R14 and R23 reservoirs have been identified as possessing the highest potential for geothermal resource development. The study also proposes a comprehensive utilization model that integrates offshore geothermal power generation with multiple applications. These findings provide a method for the evaluation of geothermal resources in the Yinggehai Basin and lay a foundation for the sustainable development of resources. [ABSTRACT FROM AUTHOR]

This paper presents a new equating method for the nonequivalent groups with anchor test design: poststratification equating based on true anchor scores. The linear version of this method is shown to be equivalent, under certain conditions, to Levine observed score equating, in the same way that the linear version of poststratification equating is equivalent to Tucker equating. Some issues related to this result are discussed.

Background: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a distinct demyelinating disease of the central nervous system. Immunoglobulin (Ig) has been used as a maintenance therapy to prevent relapses in MOGAD, but the impact of Ig on serum MOG-IgG titers is unclear. Objective: To characterize the variation in serum MOG-IgG titers after initiation of Ig treatment in people with MOGAD. Methods: We conducted a retrospective study of 10 patients with a diagnosis of MOGAD and available serum MOG-IgG titers before and after initiation of maintenance Ig treatment. Results: We found that most of the patients remained MOG-IgG seropositive while on Ig treatment with a reduced or unchanged titer, despite a lack of disease activity. Conclusions: This case series suggests that the mechanism of action of Ig therapy in MOGAD is not exclusively dependent on MOG-IgG titer reduction. [ABSTRACT FROM AUTHOR]

To enhance the resilience of power distribution networks against extreme natural disasters, this article introduces a robust fault recovery strategy for multi-source, flexible interconnected power distribution networks, particularly under scenarios of extreme disasters. Initially, the comprehensive risk of system failure due to ice load on distribution lines and poles is fully considered, and a model for the overall failure rate of lines is constructed. This model addresses the diverse failure scenarios triggered by various meteorological conditions. Through the use of information entropy, typical extreme disaster failure scenarios are identified, and lines with high failure rates underthese scenarios are determined. Subsequently, a box-type interval model is developed to represent the uncertainty in the output of distributed generation (DG), and on this basis, a robust fault recovery model for multi-source power distribution networks interconnected through soft open points (SOPs) is established, and use the Column and Constraint Generation (C&CG) algorithm to solve the problem. Finally, the fault recovery model and strategy proposed are validated through an illustrative example based on a modified IEEE 33-node interconnected system. [ABSTRACT FROM AUTHOR]

Using graphite modified polystryrene boards as insulation core materials to produce integrated composite shear walls with point connected insulation structures, and the insulation thickness varies from 100 mm to 400 mm. There are three kinds of connector materials: carbon steel, stainless steel and glass fiber. Carbon steel and stainless steel joints are wrapped in plastic to different degrees. The actual average heat transfer coefficients of different insulation thickness and different connectors are tested. The results show that for carbon steel connections, part plastic parcels can significantly improve the adverse effects on the thermal resistance of the envelope, and all plastic parcels are slightly improved compared with part plastic parcels. After plastic wrapping treatment of stainless steel connector, the adverse effects on thermal resistance are slightly improved with part and all wrapping treatment. When the insulation thickness is same, the correction coefficient of thermal conductivity of insulation material sorting: carbon steel connector system>stainless steel connector system>glass fiber connector system. [ABSTRACT FROM AUTHOR]

Image feature detection serves as the cornerstone for numerous vision applications, and it has found extensive use in agricultural harvesting. Nevertheless, determining the optimal feature extraction technique for a specific situation proves challenging, as the Ground Truth correlation between images is exceedingly elusive in harsh agricultural harvesting environments. In this study, we assemble and make publicly available the inaugural agricultural harvesting dataset, encompassing four crops: rice, corn and soybean, wheat, and rape. We develop an innovative Ground Truth-independent feature detector assessment approach that amalgamates efficiency, repeatability, and feature distribution. We examine eight distinct feature detectors and conduct a thorough evaluation using the amassed dataset. The empirical findings indicate that the FAST detector and ASLFeat yield the most exceptional performance in agricultural harvesting contexts. This evaluation establishes a trustworthy bedrock for the astute identification and application of feature extraction techniques in diverse crop reaping situations. [ABSTRACT FROM AUTHOR]