Relationships among some univariate distributions

The purpose of this paper is to graphically illustrate the parametric relationships between pairs of 35 univariate distribution families. The families are organized into a seven-by-five matrix and the relationships are illustrated by connecting related families with arrows. A simplified matrix, showing only 25 families, is designed for student use. These relationships provide rapid access to information that must otherwise be found from a time-consuming search of a large number of sources. Students, teachers, and practitioners who model random processes will find the relationships in this article useful and insightful.     

On Ultimate Damage of Material in the Stress Concentrator Zone

The authors propose the limiting damage parameters of material, which are determined from descending segments of the total deformation curves. Based on the test results for three pressure vessel steels, relationships between these parameters and the stressed state level in the stress concentrator zone have been found. The trend of these relationships is shown to be identical to that of the relationships obtained for other types of materials.     

Classifying multiclass relationships between ASes using graph convolutional network

Precisely understanding the business relationships between autonomous systems (ASes) is essential for studying the Internet structure. To date, many inference algorithms, which mainly focus on peer-to-peer (P2P) and provider-to-customer (P2C) binary classification, have been proposed to classify the AS relationships and have achieved excellent results. However, business-based sibling relationships and structure-based exchange relationships have become an increasingly nonnegligible part of the Internet market in recent years. Existing algorithms are often difficult to infer due to the high similarity of these relationships to P2P or P2C relationships. In this study, we focus on multiclassification of AS relationship for the first time. We first summarize the differences between AS relationships under the structural and attribute features, and the reasons why multiclass relationships are difficult to be inferred. We then introduce new features and propose a graph convolutional network (GCN) framework, AS-GCN, to solve this multiclassification problem under complex scenes. The proposed framework considers the global network structure and local link features concurrently. Experiments on real Internet topological data validate the effectiveness of our method, that is, AS-GCN. The proposed method achieves comparable results on the binary classification task and outperforms a series of baselines on the more difficult multiclassification task, with an overall metrics above 95%.     

A study of the effect of remanence and thickness on the recording properties of thick particulate media

The digital recording performance of a wide variety of particulate media is related to their magnetic properties. The results are compared with the somewhat divergent relationships proposed empirically and theoretically for thin metal films. It is shown that neither the empirical nor the theoretical laws consistently explain the behavior of particular media over the range of materials and compositions explored. The main points are the following. 1) For relatively low values of magnetization and relatively large thicknesses, the relationships tend to be linear more in agreement with theory. Also, the resolution is dependent upon the remanent intensity of magnetization, again in agreement with theory. 2) For relatively thin tapes having a high magnetization, the observed relationships are approximately in agreement with those found empirically for thin films.     

Pressure distribution between parallel plates arising from the molecular viscous flow of vapor during the sublimation of ice

Theoretical and experimental relationships are derived for the pressure distribution between two parallel subliming plates. The possibility of using the analytical relationships so obtained in order to choose the optimum slit height in industrial sublimation plants is discussed.     

Biomechanical aspects of work-related musculoskeletal disorders

This article provides a review of the biomechanics literature on the low back and upper extremities. Biomechanics is the study of forces acting on and generated within the body and of the effects of these forces on the tissues, fluids, or materials used for diagnosis, treatment, or research purposes. The discussion begins with an overview of basic concepts and methods. This is followed by the two literature reviews. The study selection criteria are presented at the beginning of each review. The two bodies of literature differ in maturity; the research on the low back is more substantial. The number of studies reviewed is 196 for the low back and 109 for the upper extremities. While there are certainly individual factors that put a person at risk for back pain, overall, this body of literature indicates that back pain can be related to excessive mechanical loading of the spine that can be expected in the workplace. The literature also indicates that appropriate reduction of work exposure can decrease the risk of low back disorder. Hence, it is clear, from a biomechanical perspective, that exposure to excessive amounts of physical loading can increase the risk of low back disorder. The literature also reveals that there are strong relationships between physical loads in the workplace and biomechanical loading, internal tolerances, and pain, impairment, and disability associated with the upper limb. Although many of these relationships are complex, the associations are clear. The biomechanical literature has identified relationships between physical work attributes and external loads for force, posture, vibration and temperature. Research has also demonstrated relationships between external loading and biomechanical loading (i.e. internal loads or physiologic responses). Relationships between external loading and internal tolerances (i.e. mechanical strain or fatigue) have also been demonstrated. Finally, relationships have been shown between external loading and upper limb pain, discomfort, impairment or disability. Although the relationships exist, the picture is far from complete. Individual studies have, for the most part, not fully considered the characteristic properties of physical work and external loading (i.e. magnitude, repetition or duration). Few studies have considered multiple physical stress factors or their interactions. The existence of these interactive relationships supports the load-tolerance model presented in this paper.     

The Role of Relationships and Reciprocity in the Implementation of Process Innovation

Abstract

This study examines the importance of different relationships to the implementation process for 129 projects in the North American electronics industry. The findings offer guidance on the types of relationships, or interactions, that are most likely to provide the implementer with important assistance for process innovation. Internal and external relationships were found to be important to the implementation process. The importance of reciprocity in relationships was identified. The following groups were found to be important to process implementation (listed in descending order of importance): implementer's peers, customers, suppliers, consultants, peers at sister plants, non–peer group members in the same firm, personnel at noncompeting firms, and personnel at competing firms. The relative importance of other relationships and interactions is also considered.     

不同梁理论之间简支梁特征值的解析关系

利用Euler-Bernoulli梁理论(EBT)、Timoshenko梁理论(一阶理论,TBT)和Reddy三阶梁理论(RBT)之间,梁的特征值问题在数学上的相似性,研究了不同梁理论之间特征值的关系。将特征值问题的求解转化为一个代数方程的求解,并导出了不同梁理论之间梁的特征值之间的精确解析关系。因此,只要已知梁的经典结果(临界载荷和固有频率),便很容易从这些关系中获得一阶和三阶梁理论下的相应结果。另外,从这些关系中获得的含有剪切变形影响的结果,可以用于检验一阶和三阶梁理论下梁数值结果的有效性、收敛性以及精确性等问题。     

箱形柱与工字梁连接节点翘曲变形的传递分析

箱形柱与工字形梁刚性连接节点是钢结构建筑中最常用的节点形式之一.通过对采用这种节点形式的梁柱节点处的梁柱构件之间的翘曲位移传递的研究,提出了这种节点处梁柱的翘曲位移的简单关系,并推导了在常用薄壁构件空间框架梁单元有限元模型中的实现方法.通过与壳体单元有限元的分析结果进行比较,发现壳体有限元与提出的方法结果非常吻合,同时...     

Implementation sequence of engineering and management techniques for enhancing the effectiveness of production and inventory control system

This paper discusses a methodology to determine an appropriate sequence for implementing engineering and management (E&M) techniques for enhancing the effectiveness of the production and inventory control (P&IC) system. Firstly, direct relationships among E&M techniques are analysed using the fuzzy interpretive structural modelling (FISM) approach. A procedure based on a max-min fuzzy composition of the direct relationships is also applied to determine indirect relationships among E&M techniques. Then, an appropriate implementation sequence of these E&M techniques is determined based on the driver power and dependence scores that are derived from the overall direct and indirect relationships among these techniques.     

General model for constitutive relationships of concrete and its composite structures

This paper presents a unified mathematical model that can be used to construct various constitutive relationships for concrete materials and its composite interfaces. The unified model has a single expression and a maximum of six variables/parameters, whereas in most cases, three to four parameters are sufficient. The model is simple, continuous, and easy to be integrated and differentiated. Its parameters can be assigned clear physical meanings, and used to control variations of different parts of the curve separately. Its greater versatility and flexibility enables possible applications in almost all kinds of constitutive relationships for concrete and its composite structures. For example, it is demonstrated to be suitable for stress-strain relationships of plain and confined concrete, bond-slip relationships of steel bar-to-concrete interfaces, externally-bonded fiber-reinforced polymer (FRP) interfaces, near surface mounted FRP interfaces, etc. Furthermore, a simple equation for the bond-slip relationship of steel reinforcement-to-concrete interface is derived using the unified model to replace the four-segment CEB-FIP code model.     

Dynamic hydroelastic scaling of self-adaptive composite marine rotors

The objective of this work is to establish dynamic similarity relationships for self-adaptive composite marine rotors. Although scaling laws are well established for rigid propellers and turbines, relative little work has been shown for flexible marine rotors that are designed to interact with the surrounding flow. Considering recent interests in the development of large-scale, energy-efficient composite marine propellers and turbines, it is crucial to understand the scaling relationships to properly design and interpret model-scale studies. Explanations of the similarity requirements are presented, along with scaling factors for the various fluid and structural parameters that control the dynamic interactions between the flexible rotor and the surrounding flow. Finally, numerical results obtained using a fully coupled, three-dimensional, boundary element method–finite element method is shown to demonstrate the validity of theoretical scaling relationships and to investigate scaling effects. The results suggest that for most marine rotors where gravitational forces are negligible compared to other dominant forces and the boundary layer is fully turbulent, it is most practical to conduct model-scale experiments to satisfy Mach number similarity, even though the Mach number will be much less than one for most marine applications.     

Understanding risk and uncertainty in supplier networks--a transaction cost approach

This study deals with managing risks in relationships between a larger final assembler and smaller suppliers. These relationships are often based on asymmetric cooperation where the smaller companies are highly dependent on the larger companies. This dependency can cause significant uncertainty for small and medium-sized enterprises that often operate with a narrow customer structure and minor negotiation power compared with their larger partners. The transaction cost approach (TCA) has been used as a framework for the analysis of uncertainties and risks related with these relationships. Despite the very comprehensive nature of empirical applications and theories of the transaction cost approach, these theories have not been very widely tested in the environment of small and medium-sized enterprises. Our study indicates that dependency and asymmetry are two major uncertainty and transaction cost causing drivers. Closer, long-term relationships are needed in order to minimize the transaction costs and risks. A smaller customer structure increases dependency and reduces partnership-specific transaction costs. The optimal strategy is to balance these opposite drivers. Options and linkages to the company's goals and strategies should therefore be the leading principles in balancing transaction cost uncertainty and risk. Empirical evidence from the electronics industry is presented. Alternative management approaches and further research areas are discussed.     

Large-Vector Autoregression for Multilayer Spatially Correlated Time Series

One of the most commonly used methods for modeling multivariate time series is the vector autoregressive model (VAR). VAR is generally used to identify lead, lag, and contemporaneous relationships describing Granger causality within and between time series. In this article, we investigate the VAR methodology for analyzing data consisting of multilayer time series that are spatially interdependent. When modeling VAR relationships for such data, the dependence between time series is both a curse and a blessing. The former because it requires modeling the between time-series correlation or the contemporaneous relationships which may be challenging when using likelihood-based methods. The latter because the spatial correlation structure can be used to specify the lead–lag relationships within and between time series, within and between layers. To address these challenges, we propose an L₁\L₂ regularized likelihood estimation method. The lead, lag, and contemporaneous relationships are estimated using an efficient algorithm that exploits sparsity in the VAR structure, accounts for the spatial dependence, and models the error dependence. We consider a case study to illustrate the applicability of our method. In the supplementary materials available online, we assess the performance of the proposed VAR model and compare it with existing methods within a simulation study.     

Value chain flexibility: A dichotomy of competence and capability

Increasing global competition, accelerating technological change and expanding customer expectations are creating a turbulent environment. Flexibility is a mechanism that enables firms to cope with this increasing uncertainty because it facilitates a quick response, which is strategically important as an order-winning criterion. To meet customer needs, flexibility must be across the value chain and it should include product development, manufacturing, logistics and spanning activities. The paper applies competence and capability theory to value chain flexibility and it explores the relationships among environmental uncertainty, value chain flexibility and competitive advantage. It provides a framework for understanding these relationships and builds a theoretical foundation for developing and testing relationships among these constructs. The research should help managers identify the flexible capabilities that impact relationships with their customers and the flexible competences that support these capabilities.     

Strength,density, nitrogen weight gain relationships for reaction sintered silicon nitride

Linear relationships between mean strength and nitrogen weight gain are established for isostatically pressed silicon compacts nitrided to weight gains of less than 60%. For a particular silicon powder the relationship depends upon the isostatic pressure used in compact fabrication, i.e. the green density. A linear relationship between mean strength and nitrided density is also demonstrated and this is independent of green density for the particular compacts studied. The implications of these relationships are discussed and their potential value for developing high strength reaction sintered silicon nitride explained.     

45冷轧钢在拉应力作用下的力-磁效应

在不同的最大拉应力作用下反复加载-卸载过程中,测量了45冷轧钢试件表面某确定点漏磁场随拉应力的变化关系。结果表明,当最大拉应力〈610MPa时,磁感应强度随应力的变化关系为线性关系;当最大拉应力处于610MPa与屈服点653MPa之间时,磁感应强度随应力的关系为折线关系,并且折线极值点的位置由较小应力处迅速移向较大应力位置。当最大拉应力大于屈服点时,磁感应强度的变化量保持恒定,折线极值点的位置也保持不变。从而证实了可以通过磁信号的特征对试件的安全性做出评估。     

玻璃光学碱度与三阶非线性光学极化率

介绍了玻璃光学碱度的概念,讨论了玻璃光学碱度与三阶非线性光学极化率之间的变化规律,分析了二元硼酸盐、硅酸盐、锗酸盐、碲酸盐、钛酸盐玻璃系统中光学碱度与三阶非线性光学极化率之间变化的定性趋势和定量方程,总结了玻璃光学碱度的本质及其影响,对进一步研究不同玻璃系统中光学碱度与三阶非线性光学极化率之间定量关系的趋势进行了展望.     

Supersaturation operation for quality control of crystalline particles in solution crystallization

The crystallization is widely used in chemical processes, and is one of unit operation which deals with crystallization phenomena. The purposes of crystallization are to separate desired component and to produce crystalline particles. However, phenomena of crystallization are not simple and the relationships between operation conditions and product specification are complicated. The driving force of crystallization is supersaturation in non-equilibrium process. So the operation strategy for designing supersaturation is important in order to keep high quality such as size distribution, crystal morphology and polymorph. In this paper, the relationships between supersaturation and crystal qualities are discussed, and the operation design methods are introduced to control crystal qualities in solution crystallization.