bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing a drilling fluid compensator for increasing the technological condition of drilling equipment
Authors: Minnivaleev T N , Minnivaleev A N
Published: March 2021

The phenomenon of fluctuations in pressure and fluid flow, as well as hydraulic shocks in most cases lead to negative consequences that affect the technical condition and operation of various equipment. The article discusses the causes of pressure fluctuations of the flushing liquid in the drill string and their consequences, and provides a developed compensator for the flushing liquid, which allows to smooth the flow pulsation.
Methods for increasing the efficiency of hydrochloric-acid treatments of wells
Authors: Mukhametshin V V , Kuleshova L S
Published: March 2021

The authors generalize the experience of conducting hydrochloric-acid treatments in the wells of high-viscosity oil deposits with hard-to-recover reserves in carbonate reservoirs. Intervals of changes in the values of geological and technological parameters with the efficiency of hydrochloric-acid treatment over 50% have been estimated. The impact parameters have been determined in various geological-field conditions. The causes of catastrophic water cut of wells as a result of impact have been established.
The effect of the grain size on the cycle life of spring steel 50 CrMnV
Authors: Pachurin V G , Galkin V V , Filippov A A , Pachurin G V , Mukhina M V , Smirnova Zh V
Published: March 2021

Most of the breakdown of machine parts and metal products during operation is fatigue-related due to the impact of load cycling during operation, which often leads to serious financial losses, and sometimes even fatalities. Therefore, the issues of increasing cycle life are relevant. In this work, we propose a method for predicting the cycle life of spring-type steel: the expected cycle life of steels 50CrMnV and 60SiCr in the range of 105-106 cycles can be preliminarily estimated using the equation depending on the grain size. The method allows predicting the cycle life and significantly reducing the time of its evaluation for steels such as 50CrMnV and 60SiCr by eliminating long-term fatigue tests. In addition, it also allows choosing the best performance from process treatments for the cycle life parameter without long labor-intensive fatigue tests.
Modelling the movement of log trucks with a hydro-mechanical transmission
Authors: Pitukhin E A , Skrypnik V I
Published: March 2021

The paper proposes a mathematical model of the movement of log trucks with hydro-mechanical transmission, which represents the analytical functional dependence of the speed of the log truck on the covered path. On the basis of real data it is shown that the traction characteristic of hydro-mechanical transmission is best approximated by hyperbolic regression. In this case, the solution of heterogeneous nonlinear differential equation of motion can be obtained by the approximate analytical method through decomposition of a logarithmic component in series. The calculation example showed that the obtained approximate analytical solution deviates from the numerical solution by no more than 0.002%. The obtained model allows one to determine the analytical dependencies for speed and time, which can be used to calculate the modes of movement of log trucks with the hydro-mechanical transmission.
The development of microwave installations for separating the fluff from skins of rabbits in the agricultural enterprises of low power
Authors: Shamin E , Novikova G , Mihkailova O , Prosviryakova M , Kirillov N , Storchevoj V , Zaitsev S
Published: March 2021

The article is devoted to the development of technology and technical means designed to weaken the retention force of hair in the dermis of rabbit skins due to selective dielectric heating of hair bulbs under the influence of an ultra-high frequency electromagnetic field (UHFEMF). Microwave technologies and more than 20 installations with UHFEMF sources and non-traditional resonators have been developed that provide continuous collection of fluff from rabbit skins. Resonators have been tested that ensure the separation of downy raw materials from the skin of rabbit skins in a continuous mode when implementing a set of reasonable design and technological parameters. Novelty of technical solutions of developed technologies and microwave installations with non-traditional resonators, such as: cylindrical (2655770, 2651594, 2680543, 2682890); semi-cylindrical (2018101622, 2703918); toroidal (2674605, 2699709); coaxial (2655748, 2651593); biconic (2715341, 2018117136) proved by patents of the Russian Federation. A technical specification has been developed for creating a radio-hermetic microwave installation with low-power magnetrons and a biconic resonator, which ensures the separation of down raw materials from rabbit skins in a continuous mode at low operating costs.
Positioning automation when assembling panel structures
Authors: Kovalevich M V , Shemonaeva E S
Published: March 2021

The article discusses the process of assembling low-stiffness panel structures typical of the aerospace industry. Due to the low stiffness of the incoming elements, the assembly of such structures differs from the assembly of structures typical of general mechanical engineering. To switch to a robotic assembly of such structures, it is necessary to comply with special requirements both to the technology and to the design of the elements included in the assembly. The paper investigates the process of positioning automation during the assembly of panel structures using industrial robots. The article describes a method of verification calculation for accuracy, which allows establishing whether the proposed positioning method meets the specified requirements for the aerodynamic contour of the product. Requirements for structural elements have been formulated, which will allow positioning during assembly with the required accuracy. The results obtained in the course of the study can be used in the design of new structures, the assembly of which will be carried out using automation tools. In addition, the developed requirements must be taken into account when switching to new assembly technologies for existing structures. The results of the study can help to improve the efficiency of assembly of flexible structures used in the aerospace industry. It was also found that it is necessary to conduct further research in terms of the influence of deflections of the structure from its own weight and during the supply of the tool that performs the setting of joints.
Correlation analysis to determine the relationship between the geometric dimensions and the electromagnetic moment of a switched reluctance motor
Authors: Shevkunova A V , Shapshal A S , Talakhadze T Z , Shapshal S A
Published: March 2021

An electric drive is an indispensable part of any mechanism. Without it, the the functioning of any industry is impossible, especially in the railway. It allows you to automate technological processes and increase their efficiency. For efficient railway transport, it is necessary to increase the level of technical development of traction rolling stock, which is possible through the use of promising types of electric machines, one of which is a switched reluctance motor. To create a highly efficient and technological switched reluctance electric drive, it is necessary to have information about the relationship between the geometric dimensions of its magnetic system and the average value of the electromagnetic moment. The purpose of this article is to determine the strength and direction of the relationship between the average value of the electromagnetic moment and the changing geometric values of the tooth-groove zone of the object under study. The numerical value of the electromagnetic moment was obtained using the stochastic method in the MATLAB application package, which directly interacted with the FEMM version 4.2 program, which is based on the finite element method. The research carried out in the article and the results obtained allow us to conclude that there is or is not an appropriate connection between the considered elements of the magnetic system design and the value of the electromagnetic moment.
Selection of optimal operating modes for a block cluster pumping station
Authors: Suleimanov R I , Khabibullin M Ya , Zainagalina L Z , Zaripova L M
Published: March 2021

The article discusses a method for optimizing the model of a modular cluster pumping station using a variable frequency drive. Thanks to this technology, the energy consumption of the pumping units of the installation are sharply reduced. The equipment service life increases as a result of the application of this technology.
Models and classifications of secure resource management methods in distributed information communication networks
Authors: Turluyev R R , Ivanov M Yu , Beregova G M
Published: March 2021

This paper analyzes the models and classification of secure resource management methods in distributed information communication networks in order to identify the most optimal model.
Application of the least square method for calculating the optimal well profile
Authors: Usmanova F K , Usmanova L Z
Published: March 2021

The article offers a new approach to calculating a wellbore profile of a directional well. The calculation of the well trajectory based on inclinometric studies using correlation analysis is considered. The coordinates of measurement points are calculated automatically by building a comparison table in Microsoft Excel. Based on the results of calculations, the functional relation the most fully characterizing the well path is selected. We propose the least square method for calculating the optimal well profile. According to revealed functional relation, the length of the well is determined by integration based on the calculated values of displacements. The estimation of wellbore deviation from the well profile design represented as a parabolic dependence at a certain drilling interval was performed.
Design and technological support for the assembly of long thin-walled buildings
Authors: Yamnikov A S , Rodionova E N , Matveev I A
Published: March 2021

The article considers the issue of design and technological support for the assembly of extended thin-walled buildings, in particular, the problem of ensuring their entry into the reciprocal parts that ensure the functioning of the assembled products. A new method for controlling the size of the entry of buildings is proposed. The objective of the technical solution is to reduce the complexity of control of the hulls while ensuring their entry into launch tubes. The method consists in the fact that the housing is installed in two prisms according to the extreme centering thickenings. The readings of the measuring device are taken, which judge the suitability of the housing by the diameter of the adjacent cylinder, characterized in that the indicator is installed in a plane perpendicular to one of the faces of the prism, adjusted according to the standard when touching the tip of the middle centering thickening of the standard. As a result of testing in the conditions of the current production, it was found that the verification of the product is reduced several times.
Corrosion resistance of plasma transferred arc (PTA) Inconel 625 deposits
Authors: Garcia Regina Paula , Luz Temístocles , Canobre Sheila Cristina , Costa Henara Lillian
Published: March 2021

Although the industrial sector is very restrictive in terms of the amount of dilution of the substrate allowed in welded Inconel coatings (often below 10%), the real impact of small changes in dilution on corrosion resistance of Inconel deposits is not clear yet. To evaluate this, welding current, welding speed and powder feed rate were varied within narrow ranges during PTA deposition of Inconel 625 onto carbon steel substrates. The effects of welding parameters on dilution and convexity index of the beads were analyzed within the established operational envelope. Potentiodynamic corrosion tests were carried out using solutions with different corrosion aggressiveness for specimens with different dilutions. The current of 180 A appeared as a transient point for the effects of the welding current on dilution and convexity index, suggesting a complex interaction between welding current, welding speed and powder feed rate. XRD results showed that for the specimens with higher dilution, only the region very close to the interface with the substrate was affected, suppressing the formation of the M2C. Interdendritic corrosion with preferential dissolution of some phases was observed as the main corrosion mechanism for all the deposits. The specimens with higher dilution showed tendency for secondary passivation in NaCl and NaCl + FeCl3 solutions. Moreover, the corrosion potential and corrosion current density values obtained for the specimens with lower and higher dilution were very close, with negligible differences, regardless of the position in the bead. The presence of FeCl3 in the electrolyte shifted the corrosion potential to more positive values. In the NaCl + H2SO4 solution, the deposits showed significant differences only in terms of passivation current between higher and lower dilution specimens. However, in general the differences between the deposits were negligible, showing good overall aqueous corrosion resistance in a wide range of highly aggressive environments. Therefore, this work found a relatively wide operational envelope for Inconel 625 PTA deposits, showing that small changes in deposition conditions, and thus in dilution, do not affect the coating applicability.
Atomic configuration controlled photocurrent in van der Waals homostructures
Authors: Xiong Ying , Shi Li-kun , Song Justin C W
Published: March 2021

Conventional photocurrents at a p–n junction depend on macroscopic built-in fields and are typically insensitive to the microscopic details of a crystal’s atomic configuration. Here we demonstrate how atomic configuration can control photocurrent in van der Waals (vdW) materials. In particular, we find bulk shift photocurrents (SPCs) can display a rich (atomic) configuration dependent phenomenology that range from contrasting SPC currents for different stacking arrangements in a vdW homostructure (e.g. AB vs BA stacking) to a strong light polarization dependence for SPC that align with crystallographic axes. Strikingly, we find that SPC in vdW homostructures can be directed by modest strain, yielding sizeable photocurrent magnitudes under unpolarized light irradiation and manifesting even in the absence of p–n junctions. These demonstrate that SPC are intimately linked to how the Bloch wavefunctions are embedded in real space, and enables a new macroscopic transport probe (photocurrent) of lattice-scale registration in vdW materials.
Microstructure evolution and coarsening kinetics of semisolid CuSn10P1 alloy under short-time isothermal treatment
Authors: Li Yongkun , Yu Xiangyang , Zhou Rongfeng , Li Lu , Zhang Yuanbo , Xiao Han
Published: March 2021

The key success of semisolid rheology is to prepare high-quality semisolid slurries. To achieve that it is necessary to be able to characterize the microstructure, element distribution, and coarsening mechanism during short-time isothermal treatment. This present work applied the enclosed cooling slope channel (ECSC) to make a semisolid slurry of CuSn10P1 alloy. Effects of short-time isothermal treatment (0, 5, 10, 15, 20, 25 s) on microstructure characteristics, element distribution, grain stability, and coarsening kinetics of semisolid CuSn10P1 alloy were studied. The equiaxed or near-globular microstructure can be prepared and improved intergranular segregation of CuSn10P1 alloy through the semisolid slurry short-time isothermal treatment. The mean diameter of primaryα-Cu phase gradually increases with soaking time prolonged, but shape factor shows a wavy trend. The mean size and shape factor changes caused by the instability of primaryα-Cu phase during short-time isothermal treatment can be described by the melting mechanism and the coarsening mechanism. The relationship between the high Tin layer thickness of primaryα-Cu and soaking time is consistent with the linear equation. The relationships of the Sn mass fraction in intergranular microstructure and primaryα-Cu phase center versus soaking time are consistent with an exponential equation. The suitable isothermal treatment parameters for the semisolid CuSn10P1 alloy is the soaking time 15 s to 20 s at 990 °C.
High temperature oxidation behavior and mechanism of FeXCr0.5Ti ferritic stainless steels
Authors: Jiang Xueyu , Che Xin , Zhang Zhipeng , Yin Shuying , Wang Hailong , Chen Lijia
Published: March 2021

In order to investigate the oxidation mechanism of ferritic stainless steel during long-term oxidation at high temperature. The oxidation behavior of Fe-Cr-Ti ferritic stainless steels with 10.38 wt% Cr and 17.41 wt% Cr at 800 °C and 900 °C for 100 h was studied by a constant temperature weight gain method. The morphology and composition of the oxide film were characterized by SEM, EDS and XRD. The experimental results indicate that the oxygen element mainly diffuses inward at 800 °C for two stainless steels, and the oxide film is composed of (Cr1.3Fe0.7)O3 + MnCr2O4. When the temperature rises to 900 °C, metal element mainly diffuses outward, and Fe2O3 outer oxide layer and Fe rich Fe-Cr inner oxide layer are formed in Fe11Cr0.5Ti stainless steel; Cr2O3 + Cr rich M3O4 spinel oxide film is formed in Fe18Cr0.5Ti stainless steel, while the inner layer is composed of SiO2. The main reason for the significant decrease of oxidation resistance of Fe11Cr0.5Ti stainless steel is that the low content of Cr cannot form a Cr rich oxide layer to inhibit the outward diffusion of Fe element, and the stability of oxide film is poor to protect the matrix.
Research progress of surface-modified graphene-based materials for tribological applications
Authors: Wang Mingyue , Zhou Ming , Li Xiao , Luo Chaogui , You Shengli , Chen Xin , Mo Youtang , Zhu Hongwei
Published: March 2021

Graphene’s many excellent properties have cemented it as an essential research topic in materials science and beyond. It is widely used in photoelectric materials, sensors, battery electrode materials, composites, and so on. Graphene has attracted particular attention in the field of tribology. However, graphene agglomerates easily, limiting its performance when used directly. Therefore, considerable research has focused on methods of modifying the surface of graphene to improve its tribological performance, by improving the dispersion stability, friction reduction, wear resistance, or a combination of these. This paper focuses on the research progress of surface modification of graphene-based materials for tribological applications. According to the reaction principles, surface modification methods can be divided into covalent surface modification, noncovalent surface modification, and surface modification by nanoparticles doping. Herein, the typical reaction processes of these modification methods and the anti-wear mechanism of modified graphene-based materials are introduced, and current research on the surface modification of graphene used in tribology is discussed.
The preparation and properties of polyurethane foams reinforced with bamboo fiber sources in China
Authors: Qiu Chongpeng , Li Feng , Wang Liang , Zhang Xuelun , Zhang You , Tang Qi , Zhao Xiyu , De Hoop Cornelis F , Peng Xiaopeng , Yu Xiaojuan , Huang Xingyan
Published: March 2021

Polyurethane (PU) foams reinforced with bamboo fiber sources in China, i.e., bamboo fiber, bamboo α-cellulose fiber, and bamboo nanocellulose fiber, were prepared and their physico-mechanical properties were analyzed in this work. The bamboo fiber sources and PU foams were characterized by Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), Thermal gravimetric analysis (TGA) and universal compression testing. The results indicated that the hydroxyl groups on the fiber surfaces were enhanced by removing non-celluloses in the preparation of α-cellulose and nanocellulose. With the addition of small particle size α-cellulose and nanocellulose, the cell sizes of PU foams were reduced due to more nucleating agents being introduced. The FTIR spectra confirmed that the bamboo fiber sources were involved in the foaming reaction. The PU foams with bamboo fiber sources had a higher thermal stability than neat foam, and they were satisfactory enough to be used as insulation. PU foams reinforced with 5% bamboo fiber, 3% α-cellulose fiber and 3% nanocellulose fiber had better physico-mechanical performance than other foams. The reinforcement performance of 3% bamboo α-cellulose fiber on PU foam was comparable with that of high-cost nanocellulose. Accordingly, bamboo α-cellulose fiber was demonstrated to be a promising candidate to reinforce PU foam, which could be used in the reinforcement of foam insulation.
Laser-induced breakdown spectroscopy for the classification of wood materials using machine learning methods combined with feature selection
Authors: CUI Xutai , WANG Qianqian , WEI Kai , TENG Geer , XU Xiangjun
Published: March 2021

In this paper, we explore whether a feature selection method can improve model performance by using some classical machine learning models, artificial neural network, k-nearest neighbor, partial least squares-discrimination analysis, random forest, and support vector machine (SVM), combined with the feature selection methods, distance correlation coefficient (DCC), important weight of linear discriminant analysis (IW-LDA), and Relief-F algorithms, to discriminate eight species of wood (African rosewood, Brazilian bubinga, elm, larch, Myanmar padauk, Pterocarpus erinaceus, poplar, and sycamore) based on the laser-induced breakdown spectroscopy (LIBS) technique. The spectral data are normalized by the maximum of line intensity and principal component analysis is applied to the exploratory data analysis. The feature spectral lines are selected out based on the important weight assessed by DCC, IW-LDA, and Relief-F. All models are built by using the different number of feature lines (sorted by their important weight) as input. The relationship between the number of feature lines and the correct classification rate (CCR) of the model is analyzed. The CCRs of all models are improved by using a suitable feature selection. The highest CCR achieves (98.55...0.39)% when the SVM model is established from 86 feature lines selected by the IW-LDA method. The result demonstrates that a suitable feature selection method can improve model recognition ability and reduce modeling time in the application of wood materials classification using LIBS.
Silicon breakthrough bags award
Authors: Johnston Hamish
Published: March 2021

The Physics World 2020 Breakthrough of the Year goes to researchers who have created a silicon-based material that emits light at practical wavelengths
Study finds male sexual-orientation gap in science
Authors: Allen Michael
Published: March 2021

Men in same-sex relationships are significantly less likely to have a degree in a science, technology, engineering and mathematics (STEM) field than their heterosexual peers.
Astronomers reveal most detailed atlas of the Milky Way
Authors: Banks Michael
Published: March 2021

The European Space Agency (ESA) has released the latest star map of the Milky Way taken by its €450m Gaia mission.
Japanese asteroid sample returns safely
Authors: Banks Michael
Published: March 2021

The Japanese space agency, JAXA, has announced that it has successfully retrieved rock samples from an asteroid.
China launches search for extreme cosmic events
Authors: Xin Ling
Published: March 2021

China has launched a space telescope to study some of the most energetic events in the universe.
Japan seeks to save famed observatory
Authors: Randall Ian
Published: March 2021

An international fundraising campaign has been launched on Kickstarter to help preserve Japan’s historic Kwasan Observatory
Why free will is beyond physics
Authors: Ball Phillip
Published: March 2021

Philip Ball argues that “free will” is not ruled out by physics – because it doesn’t stem from physics in the first place
Roll-to-roll fabrication of highly transparent Ca:Ag top-electrode towards flexible large-area OLED lighting application
Authors: Wang Dongxiang , Hauptmann Jacqueline , May Christian , Hofstetter Yvonne J , Vaynzof Yana , Müller Tobias
Published: March 2021

Transparency and bendability are some of the most attractive unique selling points for organic light-emitting diode (OLED) lighting, enabling a variety of new application possibilities for industrial and private end-users. The roll-to-roll (R2R) OLED fabrication based on thermal evaporation offers a fast, continuous-running solution for producing flexible OLEDs at a lower cost. In this work, R2R fabricated large-area highly transparent thermal co-evaporated Ca:Ag (2:1 vol.%) top-electrode with mean transmittance of 64% over the visible range and a corresponding sheet resistance of as low as 21 Ω sq−1 was achieved. By increasing the film thickness to 24 nm, the sheet resistance can be further reduced to 12 Ω sq−1, albeit with a lower mean transmittance of 58%. The Ca:Ag electrode demonstrates a high mechanical durability through 1000 bending cycles, which is highly desirable as a characteristic for flexible electronics, as well as for the R2R fabrication. Finally, the stability of the Ca:Ag electrode in vacuum and ambient was studied as well.
Informing drought mitigation policy by estimating the value of water for crop production
Authors: Rimsaite Renata , Gibson Justin , Brozović Nicholas
Published: March 2021

Farmers use irrigation to mitigate drought risk and reduce yield uncertainty. A clear understanding of the monetary value of irrigation water and how it varies across time and space can help to inform farmers and policymakers about the potential impacts of water shortages and reduce uncertainty in decision making. Here, we introduce a framework for understanding the economic value of water used to produce corn in the central High Plains region during the period 2010–2017. Our analysis uses publicly available data for corn price and for irrigated and non-irrigated yields and incorporates irrigation requirement adjustments to account for the hydrologic balance. The findings suggest that the per unit value of irrigation water is highest not during severe droughts and not in more arid areas of the study region, but rather when and where irrigation can make the largest improvements to average crop productivity. Policy changes informed by these results might help to mitigate the impacts of future droughts on agriculture, especially in areas where climate change may lead to large increases in supplemental irrigation.
Mesoporous PdBi film as efficient electrocatalyst for ethanol oxidation reaction
Authors: Ren Siyu , Du Dawei , Ma Lian , Li Cuiling
Published: March 2021

Developing electrocatalysts that can completely oxidize ethanol oxidation is critical for commercializing direct ethanol fuel cells. Here, we tailored synthesis of mesoporous PdBi films by employing an electrochemical-assisted micelle assembly approach. The as-prepared film exhibited superior electrocatalytic activity and stability toward ethanol oxidation reaction, which is promising forpractical applications.
Exploring MXene-based materials for next-generation rechargeable batteries
Authors: Wu Yuanji , Sun Yingjuan , Zheng Jiefeng , Rong Jianhua , Li Hongyan , Niu Li
Published: March 2021

MXenes have attracted widespread attention as a kind of emerging 2D material with unique physical and chemical properties. Due to their low adsorption energy and diffusion barrier for some metal ions, some MXenes have become very promising electrode materials for metal-ion batteries. Because of their unique structures and mechanical properties, MXenes are also used in alkaline metal batteries and lithium-sulfur batteries to maintain the integrity of the electrode structure and improve the stability of the battery’s performance. Therefore, MXenes have been widely used in various new-type battery systems. In order to understand the role of MXenes in various post-lithium-ion batteries and evaluate their application potential in these batteries, in this review, the application of MXenes in various post-lithium-ion batteries is comprehensively summarized. In addition, since the preparation methods and conditions have a great impact on the performance of MXenes, various methods for preparing MXenes have also been summarized. Furthermore, with regard to the current development situation of MXenes, we have also expressed our opinions and discussed their development directions in order to enlighten the readers.
Comparing Loihi with a SpiNNaker 2 prototype on low-latency keyword spotting and adaptive robotic control
Authors: Yan Yexin , Stewart Terrence C , Choo Xuan , Vogginger Bernhard , Partzsch Johannes , Höppner Sebastian , Kelber Florian , Eliasmith Chris , Furber Steve , Mayr Christian
Published: March 2021

We implemented two neural network based benchmark tasks on a prototype chip of the second-generation SpiNNaker (SpiNNaker 2) neuromorphic system: keyword spotting and adaptive robotic control. Keyword spotting is commonly used in smart speakers to listen for wake words, and adaptive control is used in robotic applications to adapt to unknown dynamics in an online fashion. We highlight the benefit of a multiply-accumulate (MAC) array in the SpiNNaker 2 prototype which is ordinarily used in rate-based machine learning networks when employed in a neuromorphic, spiking context. In addition, the same benchmark tasks have been implemented on the Loihi neuromorphic chip, giving a side-by-side comparison regarding power consumption and computation time. While Loihi shows better efficiency when less complicated vector-matrix multiplication is involved, with the MAC array, the SpiNNaker 2 prototype shows better efficiency when high dimensional vector-matrix multiplication is involved.
Probability inequalities for multiplicative sequences of random variables
Authors: Karagulyan Grigori
Published: March 2021

We extend some sharp inequalities for martingale-differences to general multiplicative systems of random variables. The key ingredient in the proofs is a technique reducing the general case to the case of Rademacher random variables without change of the constants in inequalities.
Hausdorff dimension of sets with restricted, slowly growing partial quotients
Authors: Takahasi Hiroki
Published: March 2021

I. J. Good [Proc. Cambridge Philos. Soc. 37 (1941), pp. 199–228] showed that the set of irrational numbers in

(
0
,
1
)

(0,1)

whose partial quotients

a
n

a_n

tend to infinity is of Hausdorff dimension

1

/

2

1/2

. A number of related results impose restrictions of the type

a
n

∈
B

a_n\in B

or

a
n

≥
f
(
n
)

a_n\geq f(n)

, where

B
B

is an infinite subset of

N

\mathbb N

and

f
f

is a rapidly growing function with

n
n

. We show that, for an arbitrary

B
B

and an arbitrary

f
f

with values in

[
min
B
,
∞
)

[\min B,\infty )

and tending to infinity, the set of irrational numbers in

(
0
,
1
)

(0,1)

such that
\[
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="a Subscript n Baseline element-of upper B comma a Subscript n Baseline less-than-or-equal-to f left-parenthesis n right-parenthesis for all n element-of double-struck upper N comma and a Subscript n Baseline right-arrow normal infinity as n right-arrow normal infinity">

a
n

∈
B
,
 

a
n

≤
f
(
n
)

 for all 

n
∈

N

, and 

a
n

→
∞
 as 
n
→
∞

a_n\in B,\ a_n\leq f(n)\text { for all $n\in \mathbb N$, and }a_n\to \infty \text { as }n\to \infty

\]
is of Hausdorff dimension

τ
(
B
)

/

2
,

\tau (B)/2,

where

τ
(
B
)

\tau (B)

is the exponent of convergence of

B
B

.
Psychoanalytic Theory
Authors: Alcorn Marshall
Published: March 2021

Although Freud’s key claims regarding unconscious processes are pervasive in psychoanalytic theory, psychoanalysis is not a singular unified system. Early originating frameworks have evolved to adapt to changing clinical practices. In Britain, Freud’s work was complicated by the work of Klein, and later by the British Object Relations school, and still later by the inclusion of empirical research from John Bowlby’s attachment theory. In France and Latin America, Lacan gained dominance; in the United States, early work in “ego psychology” was supplemented by Kohutian “self-psychology” and later by “relational psychoanalysis.” In the academy, the work of Slavoj Zizek, synthesizing Lacanian and Marxist theory, has had wide influence. All these perspectives offer different accounts of the legacies of the past in their impact on unconscious expression.

Early applications of psychoanalysis to literature were concerned with the origins of creativity and the neurotic conditions of literary characters or authors. Subsequent interests have focused on the nature of literary language and the dynamics of readerly engagements. In the early 21st century, use of psychoanalysis as an analytic tool follows the model of a conversation. The goal is not to apply a theory to a text to illustrate a psychoanalytic truth but to tease out the “unsaid” of a text or set of texts. Psychoanalysis in literary engagements, as in clinical engagements, is not about establishing a truth; instead it is used in “dialogue” with another discourse to discover implicit or unacknowledged dimensions of that articulation. The diversity of psychoanalytic schools and concepts allows scholars to give attention to wide-ranging interests: to the grip of ideology on subject, to the unconscious thematics of authors, to the symptomatic conditions of culture. Popular subjects for the psychoanalytic study of literature or film are psychic conflict, suffering, anxiety, enjoyment, the uncanny, and the repressed.

Following World War II, the Frankfurt school synthesized Freud with Marxist thought, laying out enduring parameters for the psychoanalytic study of social processes. Adorno and Horkheimer sought to understand totalitarian character and mass culture and explored literature as a response to ideological enlistment. Recent work by “the Lacanian Left” in political theory explores libidinal and affective dimensions of discourse. “Psychosocial studies” scholars in Britain utilize psychoanalytic principles to gain more complex information from interviews and social research designs. Contemporary work in neuropsychoanalysis develops empirical evidence to document psychoanalytic processes in the organizational patterns of the brain, particularly in the dynamics of dreaming, memory, and nonconscious behavior. All these newly emerging engagements with psychoanalytic thought offer opportunities for contemporary research.
Chinese Literary Theory
Authors: Cao Shunqing
Published: March 2021

Chinese literary theory has established its own comprehensive theoretical systems with various schools, and it plays a significant role in world literary theories. Although each phase demonstrates different features, Chinese literary theory basically centers on the debate of practicability and literariness, two views of literary theory, which leads to two development pathways of Chinese literary theory: one is practical, based on political and moral edification, and another is literary, based on emotional expression. The two pathways are neither independent nor irrelevant; instead, they mingle as well as confront one another, and from polarization to integration they constitute Chinese literary theory.
Classical Criticism
Authors: Ford Andrew
Published: March 2021

Classical criticism refers to a conception of the nature and function of poetry and of verbal art generally whose principles were first theorized by the sophists in 5th-century bce Greece. In contrast to traditional views, they held that eloquence was no less a product of conscious design than a house or a sculpture, and that skillful speech was an art (τέχνη) that could be learned. The expertise they claimed centered on style rather than content, and the qualities they valued tended to be formal ones: clarity, orderliness, and balance, with a sense of decorum governing all elements. Their project was repudiated by Plato in a series of searching critiques, but after being refined by Isocrates and systematized by Aristotle, the study of rhetoric—which encompassed the study of poetry in an ancillary role—constituted the backbone of higher education in the liberal arts. Classical principles determined which works would be “canonized” in the Hellenistic libraries, where literary scholars began to call themselves “critics” or judges; after Greek literary culture was imported into Rome, the exemplary authors came to be called “classic” or “of the first rank.” Classical criticism retained a central place in European education and culture that would not be undermined until the 18th century. Although Romanticism rejected 18th-century classicism as excessively rationalistic and narrowly formal, its basic concepts and terms continue to be useful because of deep dialectical tensions built into them at the time of their formation.
Equality of Treatment, Opportunity, and Outcomes: Mapping the Law
Authors: Klarsfeld Alain , Cachat-Rosset Gaëlle
Published: March 2021

Equality is a concept open to many interpretations in the legal domain, with equality as equal treatment dominating the scene in the bureaucratic nation-state. But there are many possibilities offered by legal instruments to go beyond strict equality of treatment, in order to ensure equality of opportunity (a somehow nebulous concept) and equality of outcomes. Legislation can be sorted along a continuum, from the most discriminatory ones (“negative discrimination laws”) such as laws that prescribe prison sentences for people accused of being in same-sex relationships, to the most protective ones, labeled as “mandated outcome laws” (i.e., laws that prescribe quotas for designated groups) through “legal vacuum” (when laws neither discriminate nor protect), “restricted equal treatment” (when data collection by employers to monitor progress is forbidden or restricted), “equal treatment” (treating everyone the same with no consideration for outcomes), “encouraged progress” (when data collection to monitor progress on specific outcomes is mandatory for employers), and mandated progress (when goals have to be fixed and reached within a defined time frame on specified outcomes). Specific countries’ national legislation testify that some countries moved gradually along the continuum by introducing laws of increasing mandate, while (a few) others introduced outcome mandates directly and early on, as part of their core legal foundations. The public sector tends to be more protective than the private sector. A major hurdle in most countries is the enforcement of equality laws, mostly relying on individuals initiating litigation.
Inter-Firm and Intra-Firm Managerial Mobility
Authors: Broschak Joseph P.
Published: March 2021

Inter- and intrafirm managerial mobility has emerged as a topic of growing interest among management and organizational scholars. The movement of managers within and between organizations is one of the fundamental processes that links organizations and labor markets and has been the focus of research in organizational behavior, strategy, organization theory, and entrepreneurship for more than 50 years. Managerial mobility affects career opportunities and labor market outcomes for individual managers; influences the structure, strategy, routines, and processes of organizations; and shapes the environments within which organizations operate. Thus, managerial mobility research is a key to unlocking our understanding of a wide range of organizational behaviors and outcomes at several different analytical levels.

Readers are introduced to the topic of managerial mobility and the vast body of existing research is summarized here. To help researchers understand the phenomenon, “managerial mobility” is distinguished from the more general topic of “employee mobility,” various terms that researchers have used to characterize managerial mobility processes are defined, and a distinction is made between intra- and interorganizational mobility. Next, because managerial mobility is a complex process, relevant research on the antecedents of managerial mobility is identified, categorizing some of the most important predictors into individual-, organizational-, and environmental-level antecedents. To demonstrate to researchers the importance of studying managerial mobility, some of the significant consequences of managerial mobility are highlighted, again distinguishing between consequences for individuals, organizations, and the environments in which they reside. To conclude, four potential directions for research to guide scholars and help set a research agenda on lines of inquiry on intra- and interorganizational managerial mobility are offered.
LGBTQ+ Epistolary Rhetoric/Letter Writing
Authors: VanHaitsma Pamela
Published: March 2021

Approaching letter writing as a rhetorical practice—as epistolary rhetoric—is not an obvious priority for queer studies in communication. Yet the importance of letters to LGBTQ+ studies of rhetoric have come to the fore in two key ways. In a first approach, following the long-standing use of letters as evidence within interdisciplinary LGBTQ+ histories, letters serve as vital primary sources in histories of LGBTQ+ rhetoric. Letters act as evidence of LGBTQ+ romantic, erotic, and sexual relations within queer studies of public memory. Also, acting as so-called hidden transcripts, letters document other kinds of background information about rhetorical situations. In a second approach LGBTQ+ letters have been analyzed as rhetoric. Receiving the most attention are obviously public and political letters, such as those appearing in movement publications, the rhetoric of public officials and their political campaigns, and activist letter-writing campaigns. Especially in the case of LGBTQ+ life, however, letters often blur the lines between genres that are public and private, political and intimate. As such, even those letters considered most intimate, such as romantic and erotic letters, have been theorized as forms of epistolary rhetoric. Both approaches persist and are in productive tension with each other. Whether scholars underscore how LGBTQ+ letters are rhetoric or simply draw on them as records of information, letters are indispensable sources for the development of LGBTQ+ histories of rhetoric, studies of public memory, and research on communication.
Rhetoric and Critical Cultural Studies
Authors: Sloop John M.
Published: March 2021

While each term denoting the area of “Rhetoric and Critical/Cultural Studies” denotes a broad area of academic study on its own, there are numerous to contain or capture a specific area of study. Regardless of how it gets cordoned off, the area is defined by similar themes. In one sense, the area now going under this banner begins with the march of British cultural studies (especially, the so-called Birmingham School under Stuart Hall’s leadership) into the U.S. academic discussion that began in the 1970s. As this particular study of culture found its way into communication studies departments across the country, many scholars emerging from their graduate programs were shaping the area of rhetoric and critical/cultural scholars in the very act of researching the ways meanings/ideology were constrained and enabled by the operation of the entire circuit of meaning (i.e., production, consumption, representation, identity, and regulation). As the critical/culture study of rhetoric and communication has grown, several themes have emerged: (a) the study of ideological and discursive constraints (often linked to a critique of neoliberalism); (b) the study of media ecology and its way of shaping meaning; (c) studies focusing on reception/agency/resistance; (d) studies concerning materialism and the ways communication is altered by the political economy; (e) studies based in performativity; and (f) studies based in affect theory. In general, regardless of the orientation, these studies are concerned with issues of power and action around intersectional axes such as gender, race, class, sexuality, ethnicity, class, and nationality.
Agencification in Public Administration
Authors: Verhoest Koen , van Thiel Sandra , De Vadder Steven F.
Published: March 2021

Agencification is the creation of semi-autonomous agencies: organizations charged with public tasks like policy implementation, regulation, and public service delivery, operating at arm’s length from the government. Although not a new development, agencification became very popular from the 1980s on as part of the New Public Management reforms. Three types of agencies can be distinguished, based predominantly on their formal legal features. Type 1 agencies have some managerial autonomy but do not have their own legal identity separate from the state or their parent ministry. Type 2 agencies are organizations and bodies with managerial autonomy that have their own legal identity separate from the state or their parent ministry. Type 3 organizations have their own legal identity vested in, and defined by, private law and are established by, or on behalf of, the government in the form of a private law corporation, company, or a foundation, but they are predominantly controlled by government and are at least partially involved in executing public tasks. Specific characteristics of agencies differ between countries and findings show few systematic patterns: similar tasks are charged to different types of agencies. A crucial element in the functioning of agencies is the formal and de facto interplay of autonomy and control, and how this can be explained in a static and dynamic way. Studies about agencification list three main categories of its effects: economic, organizational, and political effects. However, there is still a lot that needs to be studied about agencification, its forms, and its effects.