Irregular Layout Research Articles

How do technological choices affect the economic and environmental performance of offshore wind farms?

The ongoing energy transition towards fully sustainable energy systems requires designing wind farms looking beyond the sole levelized cost of energy, in order to concurrently ensure not only the economic profitability but also the environmental friendliness of future plants. Within this new approach to design, it becomes necessary to understand the effects that various possible technological choices have on both the economic and the environmental performance of wind farms. This study presents a framework designed to support these coupled economic-environmental assessments. The capabilities of the code are showcased by analysing the impact of different choices in terms of support structure type, specific power, tower height, powertrain type, and array and export voltage level for an exemplary offshore farm, chosen here as the IEA Wind 740-10-MW Reference Offshore Wind Plant with irregular layout. While the effects of many technological choices on the cost of energy are already well understood by industry, the present analysis shows that — at least in this specific case — climate change impacts are mainly driven by steel production, due to the massive amount of required material, but also, interestingly, by vessel activities. A low specific power, tall towers, and a high export cable voltage appear to offer the greatest potential for the concurrent improvement of the environmental and economic performance of the plant.

Efficient 2D irregular layout by vector superposition NFP and mixed-integer programming

As a typical combinatorial optimization problem, two-dimensional (2D) irregular layout is a common problem in the engineering field. No-fit polygon (NFP) is a common geometric tool for solving layout problems. Although it is necessary to calculate NFP frequently in the process of layout, the search efficiency of the NFP generation algorithm is affected. The existing unfitting polygon algorithms have difficulties in dealing with complex contours, especially irregular contours with cavities. The large-scale layout process takes the long time with the low material utilization. A vector superposition NFP (VS-NFP) method is proposed in this paper to improve the solution efficiency of 2D irregular layout problems with complex contours. Based on the VS-NFP, an improved mixed integer programming (MIP) model is built. The model increases compression constraints for high solution search efficiency. A hybrid algorithm based on the VS-NFP and MIP is proposed to solve the problem. Comparing with the existing methods, the proposed method shortens the search time and improves the material utilization. The proposed method is verified in the application of large-scale layout problems.

Research on the Healing Effect Evaluation of Campus’ Small-Scale Courtyard Based on the Method of Semantic Differential and the Perceived Restorative Scale

Many studies have proven that campus green space has healing effects, but there are few evaluation studies on the healing effects of a small-scale courtyard landscape on a high-density campus. This research comprehensively employs the method of semantic differential (SD method) and the perceived restorative scale (PRS) to construct an evaluation framework based on environmental preference and restorative evaluation in order to quantify the healing capability of small-scale campus landscapes. The findings demonstrate the following: (1) Plants close to or higher than human visual height, such as trees or shrubs, will lead to a better healing effect than lawns. An irregular layout of the plants can also bring a more beautiful aesthetic and better light than a monotonous layout, thus more strongly diverting people’s attention from pressure. (2) Users’ preferences for activity space do not depend on the scale of the activity space. (3) “Perceived quality” and “Experienced quality” represent the healing quality of the courtyard in terms of abstract feelings or atmospheres that are difficult to distinguish directly. In addition to expanding and deepening the concept of restorative space elements, this research provides some guidance for the design of healing courtyards in high-density campus environments.

Design of Agricultural Field Experiments Accounting for both Complex Blocking Structures and Network Effects

We propose a novel model-based approach for constructing optimal designs with complex blocking structures and network effects for application in agricultural field experiments. The potential interference among treatments applied to different plots is described via a network structure, defined via the adjacency matrix. We consider a field trial run at Rothamsted Research and provide a comparison of optimal designs under various different models, specifically new network designs and the commonly used designs in such situations. It is shown that when there is interference between treatments on neighboring plots, designs incorporating network effects to model this interference are at least as efficient as, and often more efficient than, randomized row–column designs. In general, the advantage of network designs is that we can construct the neighbor structure even for an irregular layout by means of a graph to address the particular characteristics of the experiment. As we demonstrate through the motivating example, failing to account for the network structure when designing the experiment can lead to imprecise estimates of the treatment parameters and invalid conclusions.Supplementary materials accompanying this paper appear online.

ECSNet: Spatio-Temporal Feature Learning for Event Camera

The neuromorphic event cameras can efficiently sense the latent geometric structures and motion clues of a scene by generating asynchronous and sparse event signals. Due to the irregular layout of the event signals, how to leverage their plentiful spatio-temporal information for recognition tasks remains a significant challenge. Existing methods tend to treat events as dense image-like or point-serie representations. However, they either suffer from severe destruction on the sparsity of event data or fail to encode robust spatial cues. To fully exploit their inherent sparsity with reconciling the spatio-temporal information, we introduce a compact event representation, namely 2D-1T event cloud sequence (2D-1T ECS). We couple this representation with a novel light-weight spatio-temporal learning framework (ECSNet) that accommodates both object classification and action recognition tasks. The core of our framework is a hierarchical spatial relation module. Equipped with specially designed surface-event-based sampling unit and local event normalization unit to enhance the inter-event relation encoding, this module learns robust geometric features from the 2D event clouds. And we propose a motion attention module for efficiently capturing long-term temporal context evolving with the 1T cloud sequence. Empirically, the experiments show that our framework achieves par or even better state-of-the-art performance. Importantly, our approach cooperates well with the sparsity of event data without any sophisticated operations, hence leading to low computational costs and prominent inference speeds.

МОНАСТИР ЧСВВ УЩЕПЛОТАХ. ІСТОРІЯ, АРХІТЕКТУРА ТА ПРОБЛЕМАТИКА ЗБЕРЕЖЕННЯ

Monasteries in the XVII–XVIII centuries to a greater or lesser extent were the cultural centers of the country, centers of theological thought, spiritual and intellectual activity. It is worth noting that the sacred buildings of that time are a sign of the presence of a certain people in the territory. The monastery in Shcheploty was a small Ukrainian monastery that played its own role in this process. This Monastery is little known, and the surviving relics are not included in the register of monuments and are not protected by the law, which threatens the preservation of part of the history of sacred architecture of Ukraine. The monastery in Shcheploty is poorly studied. There are work of Slobodyan (Slobodyan V., 1998.) in the context of wooden sacred architecture with exploration of the main historical aspects of the monastery and the first attempt of the author to conduct architectural research in 2017 (Khokhon M., 2017). On the basis of measurements, the analysis of historical data the graphic reconstruction of the lost monastery is carried out. It is worth noting that the fortifications could have different shapes and combinations. Including for the fence there are two options: 1) the fence was arranged on the crown of the shaft; 2) the fence was arranged on the outer perimeter of the defensive moat (Bogdanowski, J., 1996). Both scenarios were possible, the reconstruction was carried out for the first option and is designed to open a discussion in the scientific community and stimulate further research of the monastery. As a result of the research It is determined that the monastery consisted of two wooden churches of different times, a bell tower with a fence of the sacred territory and monastic cells with an economic part and fortifications. Archaeological excavations should determine the presence of burials near the former churches. The territory of the monastery occupied about 0.7 hectares. The overall dimensions of the fortifications in the widest part were 115x80 m. The defensive perimeter consisted of an earthen rampart, a moat, bastions on the corners, a fence and a gate. The configuration had an irregular layout close to an irregular trapezoid. It has been determined that the historic territory is privately owned and has an inappropriate purpose, which creates certain legal complications in the museification of shafts at the initiative of local authorities. The defensive relics of the monastery in Shcheploty are an important element of the history of Ukrainian defensive sacred architecture. Despite the relatively small size of the monastery, the defense system was designed in the spirit of the European fortification schools. The remains of fortifications and monasteries need to be included in the register of monuments of Ukraine.

Via-Based Redistribution Layer Routing for InFO Packages With Irregular Pad Structures

The integrated fan-out (InFO) wafer-level chip-scale package (WLCSP) is introduced for modern system-in-package designs with larger I/O counts, higher interconnection density, and small form factors. A redistribution layer (RDL) in an InFO package is an extra metal layer for interchip connections, and RDL routing is crucial for achieving desired interchip connections. In a high-density InFO package, multiple RDLs with flexible vias are often adopted. To integrate chips of different technology nodes into one package, irregular pad structures need to be considered; however, no published RDL routing work considers flexible vias or irregular pad structures. This article formulates a new RDL routing problem with unified-assigned pad pairs on a via-based multilayer multichip InFO package with irregular pad structures and presents the first algorithm for this problem. The algorithm consists of a preprocessing stage, three routing stages, and a layout optimization stage. The preprocessing stage analyzes routing resources and potential routing congestion. The first routing stage performs layer assignment based on a weighted maximum planar subset of chords algorithm to route interchip nets concurrently. The second routing stage constructs a 3-D routing graph based on partitioned octagonal tiles to handle the irregular layout structure and applies A*-search to route remaining interchip nets. The third routing stage transforms a routing graph into a network-flow model to perform concurrent routing for chip-to-board nets by applying the minimum-cost maximum-flow algorithm. Finally, we develop an efficient linear-programming-based layout optimization algorithm to find desired solutions. Experimental results show that our router can achieve 100% routablility for all benchmarks under limited RDLs, while the previous state-of-the-art work cannot.

The Activities of Informal Land Development Practices in Tudun Yan-Lihidda Settlement, Katsina State, Nigeria

Failed policies, poor governance, corruption, inappropriate regulation, dysfunctional land markets, unresponsive financial systems and a fundamental lack of political interest and the limited capacity of the governance to provide adequate serviced land and housing for the majority of the ever- increasing urban population have attributed to the rapid development of informal settlements in many of our cities for the proper and effective management of our environment. It is noticed that the practice of informal land development in Katsina Metropolis largely dominated formal system of government. Problems such as irregular layout, inadequate accessibility, substandard plots size, congestion and lack of basic facilities and amenities etc. are attributed to the practice of informal land developments. This research involved physical and social survey which was performed in examining the location and group discussion and interview with residence and informal land developers to accessed some of the physical characteristics (i.e. house plot sizes, house development ratio area and road, drainage and setback) and other facilities such as health, out-post, cemetery, refuge site through oral interview with the informal land developers of the area. Secondary data adopted was the published and unpublished sources (i.e. books, journals, thesis/projects, maps etc.) This research aimed at accessing the activities of informal land development of Tudun Yan-Lihidda in Katsina Metropolis. The objective is to evaluate some of the physical characteristics of the area and identified the problems. Possible recommendations on the identified problems were made for good living environment. Problems such as irregular layout, substandard plots size, congestion and lack of basic facilities are attributed to the problems of the practice of informal land developments. There is need for the immediate attention of the urban planning board to address such problems where necessary in the area.

Fire behaviour of deep beams under unsymmetrical loading

This paper focuses on the condition where a reinforced concrete (RC) deep beam is subjected to two concentrated loads (P1 and P2), which are positioned at respective distances a and c from bottom supports. In general, equal shear spans (a = c) and equal point loads (P1 = P2) are commonly assumed in most experimental programmes. Nevertheless, such cases are rare in practice. In contrast, due to the fact that deep beam floor normally subjects to irregular layout of column grid, deep beams are usually subjected to unequal load magnitude (load inequality or P1 ≠ P2) and unsymmetrical load positions (load asymmetry or a ≠ c). Although previous research has demonstrated the significant influences of load asymmetry and inequality on the structural performance of deep beams at room temperature, no research programme has been performed to study their influences on the fire performance of deep beams. As a result, this study is proposed to investigate the shear behaviour of unsymmetrically-loaded deep beams at fire condition, analytically and experimentally. The current research first derives a strut-and-tie-model (STM) to predict the shear capacity of RC deep beams under unequal/unsymmetrical loading conditions and at elevated temperatures. The STM takes into account the effects of unsymmetrical loading configurations, contribution of steel reinforcement on strut capacity, and thermal-induced gradient. Additionally, a test programme on six RC deep beams under fire condition is conducted for verification of the proposed model. Observations from this experimental programme show that load asymmetry and inequality have different effects on the fire performance of deep beams. To be more specific, an increase in load inequality leads to an alteration in failure mode of the deep beams, whist load asymmetry does not affect the failure mode as much. On the other hand, increasing load inequality can result in a significantly increased mid-span deflection at failure and a slightly increased failure time. Besides, effect of load inequality on deflection and failure duration depends on the loading positions. Furthermore, the proposed STM yields good agreement between test data and model predictions for unequally- and/or unsymmetrically-loaded deep beams, at both room and high temperatures.

Energy dissipation capacity for waffle-flat-plate structures subjected to bi-directional seismic loadings

The seismic capacity of buildings is usually studied through separate analysis of two orthogonal directions, then combined using empirical rules. Nevertheless, the three-dimensional nature of seismic action gives rise to interaction among its different components, especially the two horizontal ones, which can cause substantial discrepancy between the actual 3D response and the one obtained by combining uniaxial responses. The present study addresses this problem for waffle-flat-plate (WFP) structures with an irregular layout of columns from the standpoint of energy dissipation capacity. A portion of a WFP prototype structure that was built in Laboratory was subjected, simultaneously, to two horizontal components of a far-field seismic record upon a shake-table. Several shakings of increasing intensity were applied until the collapse of the structure. Afterwards, a numerical model of the specimen was developed and validated with the experimental results. The numerical model was subjected to several sets of ground motions having diverse ratios of energy input from the horizontal components. When the total energy dissipated by the structure through cumulative plastic deformations until failure was obtained for each set of accelerograms, a fairly stable quantity was found to be concentrated within a narrow range of values. Moreover, the specimen subjected to bi-directional seismic loading showed a higher ultimate energy dissipation capacity than under uni-directional loadings.

Simpler Quad Layouts using Relaxed Singularities

AbstractA common approach to automatic quad layout generation on surfaces is to, in a first stage, decide on the positioning of irregular layout vertices, followed by finding sensible layout edges connecting these vertices and partitioning the surface into quadrilateral patches in a second stage. While this two‐step approach reduces the problem's complexity, this separation also limits the result quality. In the worst case, the set of layout vertices fixed in the first stage without consideration of the second may not even permit a valid quad layout. We propose an algorithm for the creation of quad layouts in which the initial layout vertices can be adjusted in the second stage. Whenever beneficial for layout quality or even validity, these vertices may be moved within a prescribed radius or even be removed. Our algorithm is based on a robust quantization strategy, turning a continuous T‐mesh structure into a discrete layout. We show the effectiveness of our algorithm on a variety of inputs.

Evolution of the seismic vulnerability of masonry buildings based on the damage data from L'Aquila 2009 event

The purpose of this study is the analysis of vulnerability trends, with particular emphasis to the evolution of the seismic behaviour of masonry buildings over the years due to the improvements in construction practices and to the enhancement of building materials over the years, also related to the subsequent enactment of seismic prescriptions. To this aim, residential masonry buildings damaged after the 2009 L'Aquila earthquake are considered, coming from the online platform Da.D.O. (Database di Danno Osservato, Database of Observed Damage) recently released from the Italian Department of Civil Protection. General features of all the parameters available from the original database are thoroughly analysed, a selection of which is used for vulnerability analysis, namely the period of construction and the design type, the presence of structural interventions, the type of horizontal structure. Vulnerability curves are obtained through an optimization technique, minimizing the deviation between observed and predicted damage. PGA from ShakeMap is used for ground motion characterization. Damage levels defined according to the European Macroseismic Scale are considered, obtained from the observed damage for vertical structures collected during the inspections. Vulnerability curves are firstly obtained as a function of period of construction and horizontal structural types, limited to the irregular layout and bad quality vertical type only, highlighting their clear influence on seismic behaviour. Lastly, the effectiveness of retrofit intervention is evaluated comparing the vulnerability curves for strengthened masonry buildings compared to those not subjected to any retrofit interventions.

A system approach to enable digital beamforming with direct radiating arrays: The joint use of precoding and sparse arrays

SummaryDigital beamforming with an active array antenna has become, these past years, the holy grail for flexible satellite payloads. This architecture enables a power, frequency and beam steering flexibility that meets the requirements of a wide range of user terminal distributions. Matching these distributions may be challenging, especially if user terminals are co‐located. In this case, narrower beams are needed to utilise high‐frequency reuse factors while avoiding inter‐beam interference. Small beamwidths, however, require large antenna diameters, which implies for conventional antenna arrays many radiating elements and subsequently an increased complexity. A way to reduce the number of radiating elements is to resort to sparse arrays with an irregular layout of radiating elements. A disadvantage of this type of antenna is their high side lobe levels when scanning the beams. A robust on‐board precoding strategy based on the knowledge of the users' positions and the antenna gain over the coverage is proposed to mitigate the interference arising from high side lobe levels. A circular direct radiating array and a sparse direct radiating array based on a sunflower design are compared with respect to the capacities they can achieve, and the complexity of the processor required to perform full digital beamforming.

A New Approach for Determining the Control Volumes of Production Wells considering Irregular Well Distribution and Heterogeneous Reservoir Properties

The oil and gas fields are commonly developed with a group of production wells. Therefore, it can be essential for the industries to predict the performance of the production wells in order to optimize the development strategies. In practice, it frequently happens that we only hope to study the performance of a single production well. In such cases, it can be time consuming to run the reservoir simulation with the entire reservoir model to study the well performance. Hence, it can be preferred to determine the control volume (or drainage volume) of the target well from the entire reservoir and run the simulation with the small control volume to reduce the simulation cost. However, an irregular layout of the production wells and the heterogeneity of reservoir properties, which can be commonly observed in real field cases, can induce a stringent barrier for one to determine the control volumes. At present, we are still lacking a method to determine the control volumes of the production wells considering well distribution and reservoir heterogeneities. In order to overcome such a barrier, the authors proposed a new approach to divide the entire reservoir into small control volumes on the basis of the fast marching method (FMM). This approach is validated by comparing the simulation outputs of the target well calculated only with the determined control volume to those calculated with the entire reservoir model. The calculated results show that using the control volume that is determined with the proposed method to calculate the well performance can yield results that agree well with the results that are calculated with the entire reservoir model. This indicates that this proposed method is reliable to determine the control volume of the production wells. In addition, the calculated results in this work show that changing fracture length exerts a slight influence on the control volumes if the length of all fractures is increased, whereas, if only one of the fracture lengths is increased, the control volume of the corresponding well will be significantly increased. The number of the production wells and the distribution of the production well can noticeably influence the control volumes of the production wells. The findings of this study can help for optimizing the well spacing, estimating the ultimate recovery, and reducing the computational cost.

STAN: A sequential transformation attention-based network for scene text recognition

Scene text with an irregular layout is difficult to recognize. To this end, a Sequential Transformation Attention-based Network (STAN), which comprises a sequential transformation network and an attention-based recognition network, is proposed for general scene text recognition. The sequential transformation network rectifies irregular text by decomposing the task into a series of patch-wise basic transformations, followed by a grid projection submodule to smooth the junction between neighboring patches. The entire rectification process is able to be trained in an end-to-end weakly supervised manner, requiring only images and their corresponding groundtruth text. Based on the rectified images, an attention-based recognition network is employed to predict a character sequence. Experiments on several benchmarks demonstrate the state-of-the-art performance of STAN on both regular and irregular text.

Seismic Performance Assessment of an Existing RC Wall Building with Irregular Geometry: A Case-Study of a Hospital in Croatia

Buildings of strategic importance should be able to resist seismic forces in accordance with potential earthquakes that may occur at the location and remain fully operational afterwards. However, many of them were constructed before the modern principles of seismic design were known (especially regarding detailing and ductility), and therefore may be considered substandard. The first step in mitigating the seismic risk of such structures is to assess their seismic performance and, in particular, to identify their structural deficiencies. This study presents a comprehensive methodology for the seismic performance assessment of individual buildings, applied to an existing reinforced concrete (RC) hospital. This building is of an irregular layout, constructed as a structural wall system, and it is located in the seismically active region of Croatia. It includes the assessment of seismic hazards on the location, ambient noise measurements, experimental determination of structural modal parameters, creation of a detailed numerical model calibrated with experimental data, and a seismic performance assessment using various analysis methods. As a result, the building collapse mechanisms were determined and critical structural elements identified, which is the basis for future actions directed to the reduction of its risk (e.g., applications of specific measures for a target retrofit, proposal of evacuation routes and safe places inside the building, etc.).

Automatic layout of 2D free-form shapes based on geometric similarity feature searching and fuzzy matching

Two-dimensional (2D) irregular layout is widely applied in various manufacturing processes, such as sheet metal cutting, shipbuilding, and electronic component placement. An efficient layout algorithm can effectively improve the material utilization, thereby reducing manufacturing cost. But the free-form shape layout problem is very challenge as it is difficult to exactly represent a free-form shape. There is not an efficient method currently available for the 2D free-form shape layout. This paper proposes a method based on the geometric similarity feature searching and fuzzy matching for the 2D free-form shape layout. The freeman chain code is developed to describe the contour information of shapes and forward-lines to form the basis of the layout strategy. A strategy based on fuzzy matching is proposed for the layout, which includes searching geometric similarity features using the longest common subsequence and the proposed placement algorithm to complete the collision. Three computational experiments are conducted to analyze the performance of the proposed method. Experimental results show that the proposed method is feasible and effective with the good applicability to achieve a high filling rate in reduced time.

Irregular layout problem for additive production

Irregular layout problem for additive production

Efficient g-function approximation with artificial neural networks for a varying number of boreholes on a regular or irregular layout

A g-function links heat extraction rates to the mean borehole wall temperatures in geothermal heat exchangers. New computation methods are proposed continuously, becoming more accurate as they rise in complexity. In this work, it is shown how artificial neural networks can be assembled and trained to approximate g-functions rapidly and accurately for varying numbers of boreholes placed on a regular or irregular layout. This article focuses on geothermal heat exchangers made up of one to ten boreholes in a field of 30 by 30 m with various borehole geometries and soil thermal properties. After a training phase that used a database of 500,000 g-functions obtained with a block matrix formulation, a mean computation time of 11.18 ms was reached. This is 37% faster than using the block matrix formulation and represents a small fraction of the time required to simulate the fluid temperature over a 5-year period. The accuracy of the network against regular and irregular configurations of boreholes was evaluated and median errors of 0.18% and 0.39% were noted. The methodology introduced in this work is general and can be used together with any method allowing construction of g-functions.

Structural Analysis in K-POP as a Collaborative Process: focused on ‘incrementing hooks’ and ‘irregular layout of sections’

Structural Analysis in K-POP as a Collaborative Process: focused on ‘incrementing hooks’ and ‘irregular layout of sections’