Block Layout Research Articles

The synergistic effect of street canyons and neighbourhood layout design on pedestrian-level thermal comfort in hot-humid area of China

The traditional shophouse neighbourhoods (TSNs) appropriately integrated multiple variables of urban morphology for enhancement of pedestrian-level thermal comfort (PTC) in hot and humid climate zones. Understanding the synergistic effect of these design variables in TSNs on PTC is helpful for urban planners and designers. This research developed a prototype parametric TSN model to investigate the synergistic effect of four main variables: neighbourhood layout configurations, canyon type (alley, arcade street, boulevard), canyon axis orientation and canyon aspect ratio (HW). The data from the in-situ measurements in a TSN of Guangzhou in summer were used as the boundary condition for simulation in ENVI-met V4.3 and validation on the results. The Physiological Equivalent Temperature was adopted to assess PTC in different cases generated by the prototype parametric TSN model. The main findings are as follows: a) both arcade and greening had significant cooling efficiency for pedestrians, especially in East-West oriented streets; b) only the PTC in alleys was sensitive to all design variables; c) favourable PTC was shown in the neighbourhood with long East-West oriented arcade streets and that in square block layout with alleys; and d) the PTC in all boulevards dramatically responded only to HWs higher than 0.67.

Identification of Urban Functional Areas Based on POI Data: A Case Study of the Guangzhou Economic and Technological Development Zone

Functional areas are the basic spatial units in which cities or development zones implement urban plans and provide functions. Internet map big data technology provides a new method for the identification and spatial analysis of functional areas. Based on the POI (point of interest) data from AMap (a map application of AutoNavi) from 2017, this paper proposes an urban functional areas recognition and analysis method based on the frequency density and the ratio of POI function types. It takes the Guangzhou Economic and Technological Development Zone as a case study to analyze the main function and spatial distribution characteristics of the detailed functional areas. The research shows the following: (1) The POI frequency density index and the function type ratio can effectively distinguish the functions of the grid units and analyze the spatial distribution characteristics of a complex functional area. (2) The single functional area is the most common area type in the Guangzhou Economic and Technological Development Zone. The largest proportion of all areas is allocated to traditional manufacturing industry functional areas, followed by high-tech enterprises, catering and entertainment, real estate, and education and health care, in descending order. The smallest proportion is allocated to finance and insurance functional areas. (3) The current layout of the functional areas in the Guangzhou Economic and Technological Development Zone conforms to the overall requirements and planning objectives of the central and local government. The layout and agglomeration of different blocks within the economic development zone are consistent with local industry’s target orientation and development history.

A data-driven approach to grocery store block layout

Retailers are a major component of almost any supply chain and are the interface between customers and goods. A ubiquitous and important retailing segment is grocery stores, yet almost no analytical work in the block design can be found in the literature. This paper uses a data-driven approach coupled with optimization to address block layout in grocery stores with the participation of Migros, the largest retailer in Turkey. The goal is to develop an effective analytical method for solving realistic grocery store block layout problems considering data which describes revenue generation and adjacency of departments. Historic market basket data is used to characterize certain important aspects that relate to customer sales and these are used in a tabu search meta-heuristic to find layouts which are likely to enhance revenue. To consider the objectives of revenue and adjacency simultaneously, a bi-objective approach is used. A set of non-dominated designs is generated for a decision maker to consider further and the generated designs have been validated with a detailed stochastic simulation model and by the marketing experts at Migros. According to the computational results and the feedback from the industry partner, this approach is both effective and pragmatic for a data-driven, analytic design of grocery store block layouts. Layout designs which improve revenues and desired adjacencies relative to the existing store layouts are identified. While this paper focuses on a single retailer, the approach is general and given that grocery layout is similar worldwide, the method and results should be easily translatable to other retailers.

Designing flexible loop-based material handling AGV paths with cell-adjacency priorities: an efficient cutting-plane algorithm

Automated Guide Vehicles (AGVs) are widely used in material handling systems. In practice, to achieve more space utilization, safety, cost reduction, and increased flexibility, only a limited number of manufacturing cells may be preferred to have direct access to AGV travel paths, and the other cells are chosen to have no or indirect access to them. This paper investigates the problem of determining a single loop in a block layout with two criteria: loop length and loop-adjacency desirability. Unlike the traditional single shortest loop design problem, where all cells must be located next to the loop, the proposed problem considers a more realistic assumption that each cell in the block layout has a different preference with regard to being adjacent to the loop: some cells must be located adjacent to the loop, some must not be adjacent to the loop, and others can be located next to the loop but with different positive or negative priorities. The problem is formulated as a bi-objective integer linear programming model with two exponential-size constraint sets. A cutting-plane algorithm is proposed to solve the model under important methods commonly used to deal with a bi-objective model. The numerical results show the high efficiency of the proposed algorithm in large scales.

Does high-rise residential building design shape antisocial behaviour?

Purpose The purpose of this paper is to examine links between environmental design of high-rise housing communities and residents’ perceptions about antisocial behaviour (ASB). Design/methodology/approach A conceptual framework was proposed to investigate correlations between architectural design parameters and perceived severity of ASB activity. A questionnaire was administered to test the relationships. Residents of 14 public rental housing estates in Hong Kong participated, and 422 complete responses were analysed. Findings Strong correlation was discovered between elements of residential design and residents’ perceptions of ASB severity. Block layout, building height and number of flats per floor affected residents’ feelings about ASB threat. Access to outside air in communal corridors also significantly reduced residents’ complaints about ASB. Practical implications This study offers insights into how architectural design of high-rise residences might reduce residents’ perception of ASB severity. Findings impact current ASB research, but also architects’ and developers’ designs. Better planned built environments will enhance residents’ security and satisfaction, reinforcing communities. Originality/value Previous studies have ignored whether architectural design of high-rises could directly influence residents’ perception of ASB severity. This study is the first to focus on the relationship.

Evolution of the commercial blocks in ancient Beijing city from the street network perspective

The synergistic relationship between urban functions and street networks has always been a focus in the field of urban research and practice. From the perspective of street networks, by adopting space syntax, this study analyzed the deep structural characteristics and potential evolution rules of commercial blocks attached to street networks in different periods, as well as the corresponding economic, political, and cultural characteristics of ancient Beijing city over the past 800 years. By combining these with changes in the street network, we further explained the function mechanism of layout and level adjustment in commercial blocks, and the influence of the street network on commercial blocks in the process of historical change. The main conclusions included the following: (1) The urban centripetal-centrifugal siphon effect: the layout form, topological structure, and traffic mode changes in the street network had corresponding guidance for the layout and hierarchical system of commercial blocks, while the centripetal development of the street network could guide the agglomeration effect of commercial blocks, although centrifugal development caused commercial blocks to display outward evacuation. (2) Stage transformation from mutation node to smooth development: the layout of commercial blocks came to depend on the ability to cross the commuting flow center, which originally relied on the accessibility of transportation nodes as local centers. Changes in traffic modes mainly affected the adjustment of the first-level commercial blocks, which easily led to overall layout mutation. Traffic levels have an obvious positive hierarchical relation with the second- and third-level commercial blocks. (3) The adaptation of traditional commercial blocks to the needs of a modern city: affected by the different emerging times and unevenness of the original commercial foundation, commercial blocks have formed various developmental models that meet the needs of modernization, and reach a balance between cultural continuity and functional adaptation.

EFFECTS OF EPIPHYTES ON TEA PRODUCTION AND THEIR MANAGEMENT

Epiphytes are a group of non-parasitic plants that settle to obtain support from plants. Under the natural forest ecosystem, the presence of epiphytes is an indicator of unpolluted and undisturbed environment. However, massive infestation by epiphytes to commercial tree crops including tea is a concern to productivity. A study was conducted initiated to determine the influence of different management options on epiphytes which included mosses, ferns, maidenhair ferns, and tongue ferns. The study evaluated the influence of different management options on epiphytes and to determine the effect of the management options on tea yields. The experiment was laid on a field infested with epiphytes in split plot design treatment structure in a randomized complete block layout, replicated three times. In the main plots the epiphytes were manually removed from the tea bush branches whereas the control was left in situ while the subplots involved use of agricultural chemicals; Copper Nordox, Cuprocaffaro, Milraz, Hydrate of lime, Round up Turbo and control (untreated). Post-treatment scoring for 3 years of all types of epiphytes was done using a scale to determine the level of yellowing, scorching, and regrowth. Yield data were also recorded for one prune cycle of four years and data was subjected to analysis of variance. The main treatments (disturbed and undisturbed) management options did not influence the efficacy of the chemical products on epiphytic mosses but disturbance reduced (p less than or equal to0.05) levels of the epiphytic ferns. Copperbased products (Copper Nordox and Cuprocaffaro) reduced (p less than or equal to0.05) in mosses levels (reducing the degree of yellowing and regrowth) than other products and the control. However, all chemical products reduced (p less than or equal to 0.05) levels of epiphytic ferns. The removal of epiphytes on the tea branches increased (p less than or equal to0.05) the yield of tea, while chemical products were ineffective in improving yields. This study, therefore, concludes that the epiphytes on the tea frame have effects on the functioning of the tea bush and removal of the massive epiphytes is necessary for improved productivity of tea bush.

Experimental and numerical study on the dispersion of heavy gases in urban environments

Abstract Heavy gas dispersion, including gravity settling that causes longstanding high-concentration zones near the ground, has become a popular research topic in recent years. A series of wind tunnel experiments containing complex layouts of building blocks were carried out to illustrate the comprehensive effect of obstacles and environmental factors on heavy gas dispersion and distribution in urban environments. The factors of wind velocity and direction, temperature, and relative humidity were considered. Five stages of variations in the carbon dioxide concentration with respect to both, wind velocity and time, were investigated at specific positions in urban environments. This paper proposes a mathematical approach to describe the concentration increasing and decreasing stage with linear fit and polynomial fit, respectively. A critical wind velocity profile, V = 1.26 ( y 0.28 ) 0.22 , at which both, the growth rate and the maximum concentration, can be at their lowest near the source. Heavy gas accumulates obviously on streets that are perpendicular to the wind direction and can flow across the roof of buildings much more easily. Gas accumulation dangerous concentration may occur near the leeward side of building due to the low pressure effects. The influence of temperature and relative humidity was apparent mainly near the source. Meanwhile, computational fluid dynamics was used to simulate the effect of gravity settling and fluid field details. Simulation results with a realizable turbulence model were obtained to compare with the experimental data, while conservative results were obtained for the building roofs.

Using simulation in layout verification of solar module assembly workshop

Facility layout problem (FLP) contemplates the optimization of space utilization, costs, and material flow. Commercial simulation softwares are commonly used to validate layouts by simulating the real world material flow and production process. To validate a layout scenario of a solar module assembly workshop, a 3D simulation model is presented which was designed on VisualComponents software. To begin with, we introduce the layout characteristics and use the systematic layout planning (SLP) method to design the block layout of workshop. Then, we built components library which contains all the facilities needed in the production line, specifically conveyors, processing equipments, robots, buffers. Finally, we have established a simulation layout model using the components in the customized library according to the block layout, and configured the components which were allocated in the layout by setting the parameters and building the connection between components via signal. To improve the performance of the workshop, we have found the best work-in-process (WIP) value for the workshop and the optimal number of workers. Additionally, the layout model was used to test collision and reachability. It demonstrated the production process in a realistic simulation environment which helped in the sales process as well. The reusable component models we have built make it easy to build a layout within a short time and validate the effectiveness of the layout scenarios for any other projects.

Block reinforcement behavior and mechanism of soil slopes

In recent years, blocks created by pressure grouting of cement into soil were used to reinforce slopes by targeting specific weak areas. A clear understanding of the block reinforcement mechanism is essential for the accurate evaluation of the stability of block-reinforced slopes and reasonable design of block layouts. A series of centrifuge model tests was conducted to investigate the bearing capacity and the full deformation and failure behavior of block-reinforced slopes, with a focus on the influence of block layouts on the reinforcement effect. A block reinforcement with a reasonable layout was confirmed to increase the stiffness and the ultimate bearing capacity of the slope. The block reinforcement significantly changed the failure mode to the complex disturbance and destruction from slippage failure in an unreinforced slope. The block reinforcement restrained the deformation localization around the blocks and thus prevented the development of the coupling effect between the deformation localization process and the failure process in an unreinforced slope during loading. Such a reinforcement mechanism could be used to explain why the block reinforcement increased the bearing capacity and changed the failure mode of the slope. The blocks exhibited significant motion along with the development of deformation localization in the slope during loading. The block reinforcement effect was significantly affected by the rotation of blocks, which was determined by the block layout.

Effect of row spacing and plant density on grain yield and yield components of Crambe abyssinica Hochst

Understanding the influence of row spacing and plant density on grain yield and yield components of crambe is critical in order to obtain higher grain yields. Therefore, the objective of this study was to evaluate the effects of row spacing and plant density on grain yield and its components in crambe in two distinct regions of Brazil (Marechal Candido Rondon-PR, MCR-PR, and Botucatu-SP, BTU-SP). Narrow and wide row spacing (0.20 and 0.40 m) combined with four plant densities (15, 25, 35, and 45 plants m-1) were evaluated in a randomized block layout with four replications in a 2 × 4 factorial design. The experiment at BTU-SP was run under rainfed conditions with supplementary irrigation, whereas the experiment at MCR-PR was run under rainfed conditions without supplementary irrigation. Both experiments were run in soils classified as Oxisols. There was no interaction between row spacing and plant density. Highest grain yield with supplementary irrigation was observed at 0.20 m row spacing. Without irrigation, row spacing did not affect grain yield owing to the plasticity of crop. The highest grain yield was observed with approximately 30 plants m-1 at both experimental locations. A strong negative correlation was observed between final plant population and number of grains per plant. There was high plant mortality, particularly at high plant densities cultivated under irrigation. Higher mortality occurred because of high intraspecific competition and a larger disease incidence due to the higher humidity in the irrigated experiment. A mechanism of self-adjustment by plant density was observed in crambe, with its intensity dependent on plant density and environmental conditions, such as water and nutrient availability and light incidence.

Ventilation and Air Quality in City Blocks Using Large-Eddy Simulation—Urban Planning Perspective

Buildings and vegetation alter the wind and pollutant transport in urban environments. This comparative study investigates the role of orientation and shape of perimeter blocks on the dispersion and ventilation of traffic-related air pollutants, and the street-level concentrations along a planned city boulevard. A large-eddy simulation (LES) model PALM is employed over a highly detailed representation of the urban domain including street trees and forested areas. Air pollutants are represented by massless and passive particles (non-reactive gases), which are released with traffic-related emission rates. High-resolution simulations for four different city-block-structures are conducted over a 8.2 km 2 domain under two contrasting inflow conditions with neutral and stable atmospheric stratification corresponding the general and wintry meteorological conditions. Variation in building height together with multiple cross streets along the boulevard improves ventilation, resulting in 7–9% lower mean concentrations at pedestrian level. The impact of smaller scale variability in building shape was negligible. Street trees further complicate the flow and dispersion. Notwithstanding the surface roughness, atmospheric stability controls the concentration levels with higher values under stably stratified inflow. Little traffic emissions are transported to courtyards. The results provide urban planners direct information to reduce air pollution by proper structural layout of perimeter blocks.

Possibilities for the use of geothermal energy in new residential buildings in Serbia, case study: Urban blocks in city of Kragujevac

Use of RES is an important element for achieving ambitious results for CO2 emission reduction in EU, emphasized and obligated by RES Directive, among other documents. In Serbia, as a candidate country and a signatory of Energy treaty, targets set by relevant documents reflect in benchmarks set by National Action Plan for Energy Efficiency, setting the level of reduction of energy consumption until 2018 for 9%, with more ambitious projections up to 2030. This calls for extensive research of possibilities for the use of renewable energy in buildings, its potentials and possible restrictions. Since the Directive states that low amount of energy required should be covered to a very significant extent by energy from renewable sources, including energy from renewable sources produced on-site or nearby, an investigation of possibilities for application of geothermal ground probes for a typical residential urban block in the city of Kragujevac is present-ed. This enables analysis of limitations imposed by legal and physical conditions: planning guidelines, type of ground, functional requests and infrastructural capacities. Typology of characteristic urban block layouts for residential buildings is generated, leading to projections of possible area covered with ground probes and calculations of relevant energy needed for heating, based on current regulations on energy efficiency in buildings. From these calculations, percentage of defined energy needs from possible geothermal ground probes is defined, enabling estimation of geothermal energy potential for new residential building blocks.

EVALUATION OF MASS HOUSING SETTLEMENTS IN TERMS OF WIND AND NOISE CONTROL: ISTANBUL AND DIYARBAKIR AS A CASE

In mass housing apartments, the comfort and quality of living conditions may be adversely affected by wind and noise especially on balconies, terraces, gardens and around swimming pools etc. The quantitative and empirical testing of building models according to physical conditions with regard to wind and noise parameters directly affects the formation of buildings in the design process. In this paper, two cities (Istanbul and Diyabakır), which are selected from two different climatic zones in Turkey are considered as examples to create maximum comfortable usage areas depending on wind and noise effects. For mass housing settlement scenarios, common comfortable areas in terms of wind and noise were determined by using Urbawind and soundplan softwares. The relevant data and acceptance criteria related to wind and noise and applied procedure are presented in the work. Performed studies show, if the settlements have dominant wind and noise directions, it is possible to find solutions using the geometric properties of the settlement in terms of wind and noise. In general, better comfort results appear in alternatives with L-C-U shaped design features rather than point-type and linear block layouts.

Joint disparity and variable size-block optimization algorithm for stereoscopic image compression

This paper addresses the disparity map estimation problem in the context of stereoscopic image coding. It is undeniable that the use of variable size blocks offers the possibility to describe more precisely the predicted view but at the expense of a high bitrate if no particular consideration is taken into account by the estimation algorithm. Indeed more information related to the block layout, considered here as a block-length map, is required at the prediction step. This paper presents an algorithm which jointly optimizes the block-length map as well as the disparity map so as to ensure a good reconstruction of the predicted view while minimizing the bitrate. This is done thanks to a joint metric taking into account the quality of the reconstruction as well as the bitrate needed to encode the maps. Moreover the developed algorithm iteratively improves its performance by refining the estimated maps. Simulation results conducted on several stereoscopic images from the CMU-VASC and the Middlebury dataset confirm the benefits of this approach as compared to competitive block matching algorithms.

Block layout for attraction-based enterprises

This paper proposes an approach for block layout for attraction based enterprises such as theme parks, museums, casinos and exhibitions. The approach takes into account the attraction of individual entities within the enterprise and any adjacency requirements among entities while enforcing reasonable shapes. Using Moran's I of spatial statistics and a newly devised shape control method, an optimization mathematical model is established. To solve the model, a space filling curve mechanism works with a tabu search heuristic. The effectiveness and practicality of the approach are demonstrated using three layout cases including the SeaWorld San Diego Park. The approach is easy to use, effective and can readily accommodate varying degrees of preference regarding adjacencies and fixed entities.

Loop-based facility layout design under flexible bay structures

We develop heuristic procedures for concurrent design of block layout, material flow network, and input and output stations. Unlike the common practice in the flexible bay structure layout design, our objective function includes both loaded and empty flow between pairs of I/O stations. This measure of effectiveness is the main determinant of the fleet size of the vehicles, which in turn is the major driver of the total investment and operational costs in vehicle-based material handling. Our work is the first to design flexible bay structure layouts for loop-based material flow patterns. We first develop heuristic algorithms to configure the layout on the foundations of a unidirectional loop flow pattern. The loop and stations are then designed on the promising layouts. A set of improvement algorithms provide a better integration of the layout, loop, and stations.

Analysis of differences of growth and phenology of provenances of Scots pine (Pinus sylvestris) in provenance experiment at Žepče

This paper analyses the growth and phenology of fourteen European provenances of Scots pine at the international experimental plot at Zepce. The experiment with the provenances was developed during the spring of 2012 with two (2+0) year old plants. In total 1400 Scots pine saplings were planted in an experimental random block layout, fourteen provenances in four replications (4 x 25 plants). The experiment was concerned with provenances from ten European countries: Austria (Traisen, Rein, Sistrans), Bosnia and Herzegovina (Bugojno), Scotland (Shieldaig), Ukraine (Ivano-Frankivsk), Slovakia (Hanusovce), Romania (Sacueini), Norway (Narvik), Germany (Trippstadt), Poland (Raciane – Nida) and Italy (Ca del Lupo, Fenestrelle, Piani – Valda). The morphological results relate to the differences in survival, height, diameter on the root neck and the ratio of these measurements to the height of the saplings of different provenances of Scots pine. Phenological details relate to the phenology of the buds and complete formation of pine needles. All of the details researched have yielded notably different findings. The results of the research can play a significant role in reforestation as well as the preservation of the genetic wealth of Scots pine.

The zone-based dynamic facility layout problem

ABSTRACTThe dynamic facility layout problem (DFLP) is to decide the locations of the departments in a facility over multiple planning periods. The main challenge in the DFLP is that there are two conflicting objectives of the problem: minimizing the material handling cost and the rearrangement cost. The cost of changing the structure of the layout over the planning horizon is also considered. Therefore, we model and solve the unequal area zone-based DFLP (ZDFLP) where the dimensions of the departments are decision variables and the departments are assigned to flexible zones with a pre-structured positioning. A zone-based block layout inherently includes possible aisle structures which can easily be adapted to the material handling system in use. This is particularly important in the DFLP because the changes in a block layout may require structural modifications in the material handling system, which in turn may be very costly. The proposed approach also considers determining relative department locations, their dimensions, as well as input/output (I/O) points concurrently for the first time in the literature. A new matheuristic, which combines concepts from simulated annealing, variable neighbourhood search, and mixed-integer programming, is used to solve the ZDFLP with promising results.

Distributed block formation and layout for disk-based management of large-scale graphs

We are witnessing an enormous growth in social networks as well as in the volume of data generated by them. An important portion of this data is in the form of graphs. In recent years, several graph processing and management systems emerged to handle large-scale graphs. The primary goal of these systems is to run graph algorithms and queries in an efficient and scalable manner. Unlike relational data, graphs are semi-structured in nature. Thus, storing and accessing graph data using secondary storage requires new solutions that can provide locality of access for graph processing workloads. In this work, we propose a scalable block formation and layout technique for graphs, which aims at reducing the I/O cost of disk-based graph processing algorithms. To achieve this, we designed a scalable MapReduce-style method called ICBL, which can divide the graph into a series of disk blocks that contain sub-graphs with high locality. Furthermore, ICBL can order the resulting blocks on disk to further reduce non-local accesses. We experimentally evaluated ICBL to showcase its scalability, layout quality, as well as the effectiveness of automatic parameter tuning for ICBL. We deployed the graph layouts generated by ICBL on the Neo4j open source graph database, http://www.neo4j.org/ (2015) graph database management system. Our results show that the layout generated by ICBL reduces the query running times over Neo4j more than $$2\times $$2× compared to the default layout.