Original Object Research Articles

Robust Transmission Design for RIS-Assisted Secure Multiuser Communication Systems in the Presence of Hardware Impairments

This paper investigates reconfigurable intelligent surface (RIS)-assisted secure multiuser communication systems in the presence of hardware impairments (HIs) at the RIS and the transceivers. We jointly optimize the beamforming vectors at the base station (BS) and the phase shifts of the reflecting elements at the RIS so as to maximize the weighted minimum approximate ergodic secrecy rate (WMAESR), subject to the transmission power constraints at the BS and unit-modulus constraints at the RIS. To solve the formulated optimization problem, we first decouple it into two tractable subproblems and then use the block coordinate descent (BCD) method to alternately optimize the subproblems. Two different methods are proposed to solve the two obtained subproblems. The first method transforms each subproblem into a second order cone programming (SOCP) problem by invoking the penalty convexconcave procedure (CCP) method and the closed-form fractional programming (FP) criterion, and then directly solves them by using CVX. The second method leverages the minorization-maximization (MM) algorithm. Specifically, we first derive a concave approximation function, which is a lower bound of the original objective function, and then the two subproblems are transformed into two simple surrogate problems that admit closed-form solutions. Simulation results verify the performance gains of the proposed robust transmission methods over existing non-robust designs. In addition, the MM algorithm is shown to have much lower complexity than the SOCP-based algorithm.

Ship Model as a Museum Object

Ship models are the part of a significant number of collections of domestic and foreign museums. Such objects are the primary sources of knowledge and emotions, true monuments of history and culture, but often belong to the group of reproductions of museum objects, that is, reduced copies of original objects. The article analyzes the questions of the definition of ship models, correlates the definitions of these items in different sources. The author considers the model of the ship from the point of view of the functions and properties of a museum object, asserts their value as originals of significant historical and cultural significance, monuments of science and technology, objects of arts and crafts, ethnographic sources. The novelty of the research lies in the study by the author of the ship model from the point of view of the theory of the museum object. This allows us to consider ship models from other, not generally accepted positions, and consider them full-fledged museum objects, which, along with originals, have the same set of properties, qualities and features. The main conclusions of the study are, firstly, that the models of ships and vessels in the collections of museums are not secondary in relation to other material sources, and secondly, that such objects fully correspond to the concept of "cultural values", are source of knowledge and emotion.

Bridges and Bridges’ Structures in the Urban Environment

The question of the functioning of bridges and bridges’ structures in the urban environment, their significant importance in increasing not only its comfort, but also aesthetic characteristics are highlighted in the article. The world theory and practice of using bridges has shown their significant evolutionary progress. From ordinary straight communication routes, bridges gradually acquired new functions, aesthetic qualities and complex spatial solutions – to multifunctional bridges’ structures. Bridges take an active part in the creation of urban multi-level public spaces. Above-ground pedestrian bridges and flyovers convincingly prove the priority of pedestrians and bicycles over cars. They perform not only the function of overpasses. Thanks to the arrangement of such objects with greenery, small architectural forms and landscaping elements, a comfortable space for people to stay is created. Modern bridges have also become a decoration of urban spaces, original art objects, magnets of attraction for citizens and guests. They draw attention to themselves, hold the aesthetic component of the urban environment. In the further practice of their design and implementation, ecological bridges made of containers and natural plants, bicycle bridges in the city centre, museum bridges, gallery bridges, sky bridges and loop bridges found their place. And this is far from the entire list of bridges. The formation of the urban environment and the distribution of “responsibilities” between its main components (dominant-accent-background) are significantly influenced by the degree of manifestation of the compositional techniques of the relationship “city – environment”, “bridge’s structure – environment”. Modern trends in the inclusion of bridges in the urban environment are also revealed in the article. These are ecological orientation, multi-functionality, innovation in the use of technologies and barrier-free.

The Musée Napoléonien: objects, performance and encountering the ‘spectacular past’ in the long nineteenth century

Abstract: In the early months of 1903, a new play opened at the Théâtre du Château-d’Eau in Paris, La Chute de l’Aigle, telling the story of the weeks following Napoléon’s defeat at Waterloo. Though the play itself was not particularly remarkable, it is notable for the presence of a ‘Musée Napoléonien’, containing a selection of original Napoleonic objects, in the theatre’s foyer. This article takes this unusual coming together of Napoleonic display in theatre and material culture as a starting point to examine the interplay between these forms of historical representation in France in the long nineteenth century. It argues that, like theatrical performance, exhibitions of Napoleonic things—especially personal items and belongings—constituted part of the broader turn towards a ‘spectacular past’, where historical narratives and biography were mediated via entertainment and spectacle. It demonstrates how contemporaries read the display of the personal items of a historical figure in dramatic, narrative terms, underlining the interaction between the visions of the historical past being constructed in performance and in the display of historical objects. In looking at these popular opportunities for experiential engagement with the past, it suggests that—whether in theatre, in exhibitions or, as in La Chute de l’Aigle, in both—such phenomena should be understood as important elements in how historical knowledge is acquired.

Crack phase‐field enhanced finite cover method for dynamic fracture at finite strain

SummaryThis study presents an enhancement of the diffusive‐discrete crack transition scheme (10.1002/nme.7169) to describe dynamic fracture at finite strain. In the enhanced scheme, the crack initiation, propagation, and bifurcation processes are determined from an energy minimization problem based on crack phase‐field theory, and the predicted diffusive crack is replaced by the discrete representation using the finite cover method. In the meantime, numerical damping is introduced to maintain computational stability and avoid distortion of the physical mesh in the finite cover context. By taking advantage of the features of the diffusive‐discrete crack transition scheme, the proposed approach enables us to stably simulate a series of dynamic fracture events involving crack initiation at an arbitrary location, propagation, and bifurcation in arbitrary directions, arbitrary divisions of an original object into multiple portions, and independent motions of divided portions. After spatial and temporal discretizations by the finite cover method and the Newmark method are described, as well as the simulation algorithm of the enhanced finite cover‐based staggered iterative procedure for dynamic fracture, several representative numerical examples are presented to demonstrate the performance and capabilities of the developed approach.

Fast solution of reliability-based robust design optimization by reducing the evaluation number for the performance functions

PurposeThe paper proposed a fast procedure for solving the reliability-based robust design optimization (RBRDO) by modifying the RBRDO formulation and transforming it into a series of RBRDO subproblems. Then for each subproblem, the objective function, constraint function and reliability index are approximated using Taylor series expansion, and their approximate forms depend on the deterministic design vector rather than the random vector and the uncertain estimation in the inner loop of RBRDO can be avoided. In this way, it can greatly reduce the evaluation number of performance function. Lastly, the trust region method is used to manage the above sequential RBRDO subproblems for convergence.Design/methodology/approachAs is known, RBRDO is nested optimization, where the outer loop updates the design vector and the inner loop estimate the uncertainties. When solving the RBRDO, a large evaluation number of performance functions are needed. Aiming at this issue, the paper proposed a fast integrated procedure for solving the RBRDO by reducing the evaluation number for the performance functions. First, it transforms the original RBRDO problem into a series of RBRDO subproblems. In each subproblem, the objective function, constraint function and reliability index caused are approximated using simple explicit functions that solely depend on the deterministic design vector rather than the random vector. In this way, the need for extensive sampling simulation in the inner loop is greatly reduced. As a result, the evaluation number for performance functions is significantly reduced, leading to a substantial reduction in computation cost. The trust region method is then employed to handle the sequential RBRDO subproblems, ensuring convergence to the optimal solutions. Finally, the engineering test and the application are presented to illustrate the effectiveness and efficiency of the proposed methods.FindingsThe paper proposes a fast procedure of solving the RBRDO can greatly reduce the evaluation number of performance function within the RBRDO and the computation cost can be saved greatly, which makes it suitable for engineering applications.Originality/valueThe standard deviation of the original objective function of the RBRDO is replaced by the mean and the reliability index of the original objective function, which are further approximated by using Taylor series expansion and their approximate forms depend on the deterministic design vector rather than the random vector. Moreover, the constraint functions are also approximated by using Taylor series expansion. In this way, the uncertainty estimation of the performance functions (i.e. the mean of the objective function, the constraint functions) and the reliability index of the objective function are avoided within the inner loop of the RBRDO.

Historical sources in exam tests: An analysis of school leaving exam tasks in terms of the use of primary sources

AbstractIn 2005 the Hungarian school-leaving examination system underwent a significant transformation. In case of history the aim was to give a greater role to the development of students' knowledge acquisition and source analysis skills by more focusing on students' work with historical sources in classes. However, it was clear that the achievement of these goals would also depend on the new exam tasks. Those determine whether the reform will be able to get real change. So I carefully examined those tasks of the past fifteen years exams that contained primary sources. I wanted to give an accurate picture of which types of tasks were most frequent and how they could be assessed in terms of the original objectives of the reform and the competency requirements of the school leaving examination. Based on the conclusions drawn from the results of the investigation, I formulate proposals for changing the composition of the exam tasks and preparing for writing the tasks.

Nepal's community forestry: critical reflection from the governance perspective

ABSTRACT In recent decades, the role of community forestry (CF) has been to address the livelihoods of local people beyond its original objective of forest protection. Yet, there have been governance-related concerns, particularly the distribution of benefits among group members. We used a case study approach to better understand the CF model from the perspective of household satisfaction and benefit distribution at the local level. For data collection, we used multiple methods, including key informant interviews, focus group discussions, and household surveys. The study utilised the Henry-Garret ranking for analysing key elements of forest governance and a probit regression model for identifying the major contributing factors of satisfaction towards CF governance. Results suggested greater equity in CF governance and the empowerment of marginalised forest communities. Though CF has created new opportunities to consolidate forest users’ efforts toward provisioning broader environmental services, the system continues to favour elites and other influential groups in CF decision-making. The study suggests improving equity and introducing incentives to primary forest dependents. The additional incentives will not only help communities to adapt to the changing context but also increase their interest in decision-making, particularly for equitable distribution of benefits and local collective action.

Auditivierung des textkritischen Apparats

Abstract Since their emergence in the 19th century, the aim of critical editions has not only been to publish philologically reliable texts, but also to make the decisions on the basis of the editorial process as transparent as possible. In the specific case of the music edition, however, the formulation of editorial decisions in a critical apparatus is complicated by the semiotic discrepancy between the sign system of musical text and its verbalised annotation in the fundamentally different sign system of linguistic text. This unbridgeable medial gap between the musical text and its verbal account caused the original editorial object to be split apart within printed editions of the 20th century: between the edited text and the critical report on the one hand, and again between practical editions for the general public and scholarly editions for the small circle of qualified musicologists on the other hand. Using the Digital Mozart Edition as an example, this article shows how a digital format can, through its audio-visual multimedia, both create spaces for the integration of the critical apparatus into the edited text and enable a ‘deverbalization’ of the critical vocabulary that conveys the documentation of editorial decisions in musical form more intuitively and more precisely. The digital medium makes it possible for critical editions of music to come closer to the ideal of an open edition in the sense of an ‘edition of the edition’, in which not only the text itself, but also the editorial process that led to this text is, in turn, edited and made immediately accessible to the user.

Acoustic cloning

Cloning refers to producing copies of objects that cannot be distinguished from the original based on their behavior or response. Here, we present a general methodology to clone objects that scatter acoustic waves and demonstrate it experimentally. We acquire digital twins and bring them back to life—a simple two-step process. First, we place the scattering object in a circular receiver aperture and insonify it from the outside using simple speakers. From the recorded data, which may be reverberative, we retrieve the object's scattering Green's functions for radiation conditions using a technique called multi-dimensional deconvolution. This process recovers the temporal and spatial bandwidth and removes the scattering interactions with the boundaries of the experimentation domain, if present. In the second step, the acoustic scatterer is removed and reconstructed holographically using the acquired scattering Green's functions. The hologram scatters arbitrary incident wavefields in real-time exactly like the original object. Low-latency feedback enables reproducing all orders of wave interactions between physical scatterers and the numerical hologram. The two-step process is demonstrated by cloning several rigid scatterers in a two-dimensional acoustic waveguide. Applications range from fully realistic digital scattering models to efficient meta-material experimentation. [Work supported by SNSF grant 197182.]

Impact on quality and diversity from integrating a reconstruction loss into neural audio synthesis

In digital media or games, sound effects are typically recorded or synthesized. While there are a great many digital synthesis tools, the synthesized audio quality is generally not on par with sound recordings. Nonetheless, sound synthesis techniques provide a popular means to generate new sound variations. In this research, we study sound effects synthesis using generative models that are inspired by the models used for high-quality speech and music synthesis. In particular, we explore the trade-off between synthesis quality and variation. With regard to quality, we integrate a reconstruction loss into the original training objective to penalize imperfect audio reconstruction and compare it with neural vocoders and traditional spectrogram inversion methods. We use a Wasserstein GAN (WGAN) as an example model to explore the synthesis quality of generated sound effects, such as footsteps, birds, guns, rain, and engine sounds. In addition to synthesis quality, we also consider the range of sound variation that is possible with our generative model. We report on the trade-off that we obtain with our model regarding the quality and diversity of synthesized sound effects.

Options for integrating architectural minimalism into the original site being renovated and modernized on the example of john pawson’s architecture

The article examines architectural minimalism projects designed on the basis of buildings being reconstructed and, at the same time, modernized, using the example of the works (1995–2022) created by the minimalist architect John Pawson. The projects considered in the study were divided into four groups of integration options, which achieve a synthesis between the original object and architectural minimalism.

A bundle-type method for nonsmooth DC programs

A bundle method for minimizing the difference of convex (DC) and possibly nonsmooth functions is developed. The method may be viewed as an inexact version of the DC algorithm, where each subproblem is solved only approximately by a bundle method. We always terminate the bundle method after the first serious step. This yields a descent direction for the original objective function, and it is shown that a stepsize of at least one is accepted in this way. Using a line search, even larger stepsizes are possible. The overall method is shown to be globally convergent to critical points of DC programs. The new algorithm is tested and compared to some other solution methods on several examples and realistic applications.

Frege’s Theory of Proper Names

Gottlob Frege, in order to explain the relationship between language and reality, believes that in addition to the subjective meaning and external reference of words, related to the words and signs in their entirety, there is also a third thing that expresses how the words designate or stand for external references. Frege calls this third phenomenon the sense of words. Sense is the mode of presentation of reference which is designated by a proper name. Sense contrary to meaning, which is subjective and personal, is an objective and external matter that everyone can enjoy or access to it. Frege’s theory will be examined in this article with the aim of showing how the theory is incomplete. Besides the fact that there is an inconsistency in his view concerning the nature of meaning (Frege considers sense sometimes objective and on other occasions something imaginary.), his argument to prove the objectivity of sense is unsuccessful. Even if we accept his assumption of the objectivity of sense, Frege cannot drive the problem of psychologism out of the path of human knowledge. That is, Frege fails to achieve its original objective; proving that psychologism is wrong.

Direct determination of glyphosate and its metabolite in the plant raw material and environmental objects by chromatography-mass spectrometry

Glyphosate is a popular herbicide often used for desiccation of crops. The use of glyphosate-based chemicals leads to the contamination of agricultural products, soils, surface and groundwater. For safety control of raw materials of the plant origin and environmental objects, a technique based on the tandem chromato-mass-spectrometry was developed to provide for the quantitative determination of glyphosate and aminomethylphosphonic acid (AMPA) without prior derivatization. The technique is characterized by a relatively simple and cost-effective sample preparation procedure. The compounds are extracted from plant raw materials with an acetic acid solution of methanol in water, in the presence of 2-aqueous disodium salt of ethylenediamine-N,N,N’,N’-tetraacetic acid (EDTA-Na2) and dichloromethane. Extraction of analytes from water samples is carried out in the presence of EDTA-Na2 and acetic acid; whereas their extraction from soil samples is carried out with a weak solution of ammonia. The extracts are purified by solid phase extraction (SPE), and proteins are precipitated with acetonitrile. Linear-dynamic ranges of glyphosate and AMPA determination are characterized by calibration curves with correlation coefficients (R) ≥0.99. The working range of glyphosate and AMPA determination in raw materials of plant origin was from 0.1 to 5.0 mg/kg; in surface and ground water from 0.001 to 0.05 mg/liter (glyphosate) and from 0.002 to 0.05 mg/liter (AMPA); in soils from 0.02 to 0.8 mg/kg (glyphosate) and from 0.04 to 0.8 mg/kg (AMPA). The values of the relative standard deviation range from 1.8 to 19.5%, with recovery levels ranging from 80.5 to 108.1%. The achieved values of the determination limits are consistent with the maximum permissible levels indicated in TR CU 015/2011 and SanPiN 1.2.3685–21.

Induced permutations for approximate metric search

Permutation-based Indexing (PBI) approaches have been proven to be particularly effective for conducting large-scale approximate metric searching. These methods rely on the idea of transforming the original metric objects into permutation representations, which can be efficiently indexed using data structures such as inverted files.The standard conceptualization of permutation associated with a metric object involves only the use of object distances and their relative orders from a set of anchors called pivots. In this paper, we generalized this definition in order to enlarge the class of permutation representations that can be used by PBI approaches. In particular, we introduced the concept of permutation induced by a space transformation and a sorting function, and we investigated which properties these transformations should possess to produce permutations that are effective for metric search. Furthermore, as a practical outcome, we defined a new type of permutation representation that is calculated using distances from pairs of pivots. This proposed technique allowed us to produce longer permutations than traditional ones for the same number of object-pivot distance calculations. The advantage lies in the fact that when longer permutations are employed, the use of inverted files built on permutation prefixes leads to greater efficiency in the search phase.

Inferring shape transformations in a drawing task.

Many objects and materials in our environment are subject to transformations that alter their shape. For example, branches bend in the wind, ice melts, and paper crumples. Still, we recognize objects and materials across these changes, suggesting we can distinguish an object's original features from those caused by the transformations ("shape scission"). Yet, if we truly understand transformations, we should not only be able to identify their signatures but also actively apply the transformations to new objects (i.e., through imagination or mental simulation). Here, we investigated this ability using a drawing task. On a tablet computer, participants viewed a sample contour and its transformed version, and were asked to apply the same transformation to a test contour by drawing what the transformed test shape should look like. Thus, they had to (i) infer the transformation from the shape differences, (ii) envisage its application to the test shape, and (iii) draw the result. Our findings show that drawings were more similar to the ground truth transformed test shape than to the original test shape-demonstrating the inference and reproduction of transformations from observation. However, this was only observed for relatively simple shapes. The ability was also modulated by transformation type and magnitude but not by the similarity between sample and test shapes. Together, our findings suggest that we can distinguish between representations of original object shapes and their transformations, and can use visual imagery to mentally apply nonrigid transformations to observed objects, showing how we not only perceive but also 'understand' shape.

Learning Context Restrained Correlation Tracking Filters via Adversarial Negative Instance Generation.

The tracking performance of discriminative correlation filters (DCFs) is often subject to unwanted boundary effects. Many attempts have already been made to address the above issue by enlarging searching regions over the last years. However, introducing excessive background information makes the discriminative filter prone to learn from the surrounding context rather than the target. In this article, we propose a novel context restrained correlation tracking filter (CRCTF) that can effectively suppress background interference via incorporating high-quality adversarial generative negative instances. Concretely, we first construct an adversarial context generation network to simulate the central target area with surrounding background information at the initial frame. Then, we suggest a coarse background estimation network to accelerate the background generation in subsequent frames. By introducing a suppression convolution term, we utilize generative background patches to reformulate the original ridge regression objective through circulant property of correlation and a cropping operator. Finally, our tracking filter is efficiently solved by the alternating direction method of multipliers (ADMM). CRCTF demonstrates the accuracy performance on par with several well-established and highly optimized baselines on multiple challenging tracking datasets, verifying the effectiveness of our proposed approach.

Nuclear and Orbital Characterization of the Transition Object (4015) 107P/Wilson–Harrington

Comet 107P/Wilson–Harrington, cross-listed as asteroid 4015, is one of the original transition objects whose properties do not neatly fit into a cometary or asteroidal origin. Discovered in a period of apparently gas-dominated activity in 1949, it was subsequently lost and recovered as the inactive asteroid 1979 VA. We obtained new and reanalyzed archival observations of the object, compared to meteorites, and conducted new orbital integrations in order to understand the nature of this object and to understand where it falls on the asteroid–comet continuum. Wilson–Harrington’s reflectance spectrum is approximately neutral from visible to near-infrared wavelengths, but has a reflectance maximum near 0.8–0.9 μm. The object’s spectrum is well matched by laboratory spectra of carbonaceous chondrite meteorites like the CM Murchison or the C i Ivuna. The object’s phase curve slope is compatible with either an asteroidal or cometary origin, and its recent orbital history has no periods with high enough temperatures to have altered its surface. While it is possible that some unknown process has acted to change the surface from an originally cometary one, we instead prefer a fundamentally asteroidal origin for Wilson–Harrington, which can explain its surface and orbital properties. However, this would require a way to maintain significant (hyper)volatile supplies on the near-Earth objects beyond what is currently expected. Wilson–Harrington’s similar meteorite affinity and possible orbital link to sample return targets (162173) Ryugu and (101955) Bennu suggest that the returned samples from the Hayabusa-2 and OSIRIS-REx missions might hold the key to understanding this object.

Penggunaan Media Pembelajaran dengan Benda Konkret untuk Meningkatkan Kemampuan Berhitung pada Peserta Didik Kelas II

Learning outcomes are described as written statements of what a learner is expected to know, understand and/or be able to do at the end of a period of learning", which means that learning outcomes are statements about what students are expected to know at the end of learning Learning media in education is something that absolutely must be used in achieving learning goals. Today's reluctance to use media is widely felt by teachers for complicated and troublesome reasons. Concrete media is the easiest tool to use, because we don't need to make any preparations other than using it right away. What is meant by real objects as media are tools for conveying information in the form of real or original objects or objects that have not undergone significant changes. Based on some of the definitions above, it can be concluded that these concrete objects are actual objects, objects or media that help students' real experiences.