Original Floor Research Articles

Longwall Face Automation: Coal Seam Floor Cutting Path Planning Based on Multiple Hierarchical Clustering

Space adaptability between mining equipment and coal-rock mass, to ensure the machines cut in a coal seam, is an importance technique in longwall mining automation. In order to guide the mining equipment cutting in the coal seam, a cutting path planning method based on multiple hierarchical clustering was proposed. Morphology similarity and the coplanarity measurement method were defined to evaluate the similarity of clusters. The coal seam floor series in the face-advancing direction were clustered according to the morphology similarity and coplanarity, respectively. Taking the morphology-based and coplanarity-based cluster centers as generating lines and stretching angle, respectively, the coal seam floor was reconstructed. The reconstructed floor can be regarded as the cutting path. The coal seam geological model of the 18,201 longwall face was analyzed with the proposed cutting path planning method. Comparing the reconstructed floor and original floor, the amounts of coal left and cut gangue were 1999 m3 and 1856 m3, respectively, for the segmental floor. For the case of whole floor, the amounts of coal left and cut gangue were 5642 m3 and 5463 m3, respectively. The coal loss rates only were 0.57% and 0.87% for the segmental and whole coal seam, respectively.

Thermal response of a curtain wall framing system under fire conditions

Curtain walls are the most common façade system for modern office buildings. These facade systems play an important role in containing the fire to the floor of origin, and in the case of failure, the consequences can be severe. The heat from a fire could cause key elements to fail and sections of the facade to detach and fall from the building, facilitating flame spread to upper floors. However, no tools currently exist that can reliably predict the failure of such systems. This study computationally investigates the thermal response of two curtain wall framing systems to fire exposure – the stick system and the unitized system. The model predictions were validated against experimental data and the role of the screw connector is explored. A typical curtain wall aluminium frame system is modelled. The simulation results indicate that when heated from a compartment fire, thermal degradation of the aluminium frame is very rapid, occurring within the first 15 min of fire exposure for ISO-834 standard fire. When heated from the outside, considering the Eurocode external fire, thermal degradation of the pressure plate occurred within 10 min. With the addition of thermal protection or when using steel instead of aluminium profiles, thermal degradation was not predicted within the first 40 min of heating. The findings advance our understanding of curtain wall frame fire behaviour and can help develop more effective fire strategies and more resilient systems.

Recursos gráficos para el posicionamiento SIG y análisis de la fortificación del siglo XX. Búnkeres en el entorno del peñón de Gibraltar

<p>Tras finalizar la guerra civil española se procedió al establecimiento de un sistema fortificado en la orilla Norte del Estrecho de Gibraltar. De entre sus componentes, destaca la red de búnkeres o fortines para la defensa del litoral, con enorme interés histórico como un eslabón más de la cadena evolutiva de la fortificación. A pesar de contar con tutela institucional, su valor patrimonial aún es objeto de debate, y los búnkeres permanecen ignorados y abandonados a su suerte.</p><p>Para visibilizar estos elementos y profundizar en su conocimiento, se plantea una estrategia fundamentada en la utilización de diversos recursos gráficos, aprovechando la documentación encontrada en los archivos militares: georreferenciación de los planos de situación e identificación de los fortines para su inventariado, a través de Sistemas de Información Geográfica; y análisis arquitectónico a partir de los planos originales de planta y sección, así como de diversos levantamientos tridimensionales.</p>

Design of Emergency Evacuation Scheme for Louvre

In this paper, we used four steps in analyzing the optimal model of evacuation within the Louvre. For step 1, we refer to the traffic concept in the Dynamic Network Flow Model to define the export throughput. For step 2, considering that the original floor plan is segmented with pixel points as a unit with high complexity and little meaning, we simplify the floor plan when the model is guaranteed to be true. For step 3, we first mark the exit node, make its dual graph, and draw the point chain containing the exit node, which can divide the original image into several pieces according to the area. Breadth-First Search from each egress node can mark themselves with color, ownership and other information. For Step 4, in order to get the optimal segmentation which satisfies the definition of reasonable segmentation edge set, we use Genetic Algorithm to solve the optimization problem. A sequence consisting of the sequence numbers in the set of Edge-Cut is encoded as a gene in the Genetic Algorithm and iterated by the Theory of Chromosome Cross-Variation to obtain an optimal solution. Finally, we have designed a scientific and complete emergency evacuation plan.

Effect of air exhaust location on surgical site particle distribution in an operating room

This study investigates effect of exhaust outlet location on airflow and particle distribution in an operating room with laminar ventilation system (LAF) via computational fluid dynamics (CFD). Four different exhaust opening configurations are comparatively examined: floor level, central level, ceiling level and floor & ceiling level. Three different particle diameters (5,10 and 20 μm) are considered for a constant value of the air change rate (30 ACH). Deposited particle numbers to operating table and to instrument table are given and compared for different particle diameters and exhaust outlet cases. It is shown that the exhaust configuration in which both floor & ceiling level air outlets employed together shows the best performance in terms of lowest particle deposition to the operating table. For this case, compared to original floor level exhaust outlet design, the total number of particles deposited on the operating table decreased by 64% for the smallest particle diameter (5 μm) and 26% for the largest particle diameter (20 μm).

Development and validation of the Rapid Positive Mental Health Instrument (R-PMHI) for measuring mental health outcomes in the population

BackgroundThe multidimensional Positive Mental Health Instrument (PMHI) has 47 items and six subscales. This study aimed to develop and validate a short unidimensional version of the PMHI among Singapore’s adult resident population.MethodsUsing pooled data from three earlier studies (n = 1050), PMHI items were reduced by Partial Credit Rasch Model (PCRM) runs in a random split-half sample, while psychometric properties of the resulting measure were tested through confirmatory factor analysis (CFA), item response theory-graded response model and internal consistency reliability in the other half. Its reliability, construct and concurrent validity, agreement with the original scale, floor and ceiling effect, and scale estimates were further investigated in an external representative general population sample (n = 1925).ResultsThe average age of the participants was around 41 years. Four PCRM re-runs for item selection resulted in a 6-item unidimensional Rapid PMHI (R-PMHI). CFA confirmed the unidimensional structure of the R-PMHI in the internal (RMSEA = 0.075, CFI = 0.985, TLI = 0.974) and external (RMSEA = 0.051, CFI = 0.992, TLI = 0.987) validation samples. In the external validation sample, the R-PMHI met concurrent validity criteria, showing high agreement with the 47-item version with intra-class correlation coefficient of 0.872 (95% CI: 0.861 to 0.882) and low floor and ceiling effects. Weight-adjusted mean (SE, 95% CI) R-PMHI score in the population was 4.86 (0.2, 4.82–4.90).ConclusionThe unidimensional 6-item R-PMHI offers brevity over the original multidimensional measure while appropriately representing the positive mental health construct. Prospective studies are needed to assess its responsiveness and test-retest reliability.

LAND AND WATER RESOURCES ASSESSMENT FOR SUSTAINABLE AGRICULTURAL DEVELOPMENT IN EL-KHARGA OASES BY USING REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM

El-Kharga Oases, New Valley governorate, Egypt was selected as a study area. It is located between latitudes 25o15ʽ and 26o05 ʽN. and longitudes 30o05 ʽ and 30o45 ʽE., having an area of 18813.8 km2. The aim of this investigation is to study the characteristics of soils and groundwater in this area for evaluating their capability and suitability for growing main crops using RS and GIS. The obtained geomorphic map showed that, the area comprises three distinct geomorphic units namely, high land (28.8%), plateau (39.3%) and depression floor (31.9%). The depression floor of various origin and almost flat areas is the main landforms and suitable units for developmental plans. The soils were classified up to sub great group level on the basis of Soil Survey Staff (2014). Land evaluation was conducted using a model depend on the bases of Sys & Verheye index and land suitability for irrigated agriculture. Accordingly, the current capability of the studied soils was classified as: fair (III) for about 45% from the studied area, poor IV (about 50%) and very poor N for the remaining area. By executing a suitable improvement practices, these classes could be developed to the following three potential capability classes; good (II), fair (III) and poor (IV). Also, soil suitability for growing specific field, vegetable and fruit crops were evaluated in the studied geomorphic units. The quality evaluation of ground water resources showed that, the pH values ranged from ultra-acid (3.47 north El-Kharga) to slightly alkaline (7.83 in Max Qibly). The salinity of ground water changed from 0.48 to 119 dS m-1 indicating non-saline to very extremely saline, TDS values varied from 307.2 to 71424 ppm (fresh, brackish, to extremely saline water). Total hardness varied from soft to very hard.

Intersample distance in radiofrequency-based through-the-wall mapping for acceptable reconstruction quality

The ability to obtain reconstructed floor maps of acceptable quality with less samples speeds up the acquisition phase, which is of the highest relevance for most radio-frequency (RF)-based through-the-wall mapping (TWM) applications, particularly in the area of law enforcement and security. The key issue impacting the acquisition time is the quantity of necessary samples for acceptable floor reconstruction quality, which in turn depends on the intersample distance. We evaluate the impact of enlarging the intersample distance in the reconstruction quality of an algebraic method applied to RF-based TWM, under a parallel-beam acquisition geometry. Finite-element method (FEM) is used to define a physical model, allowing high accuracy in the simulation results. Two test floor maps are built in the FEM model, and the correspondent very-high frequency RF samples are generated in each case, composing the so-called sinograms. The sinograms are forwarded to the algebraic reconstruction method—simultaneous iterative reconstruction technique—to provide estimates of the original floor maps. In simulations, the use of sinogram upsampling to improve image resolution leads to floor maps of acceptable reconstruction quality in a parallel-beam RF-based TWM setup with intersample distances up to two wavelengths for an angular step of 4.5 deg.

Failure of a warehouse floor by subsoil settlement

This paper discusses the failure of a warehouse floor (with an approximate surface area of 1.550 m2) inside an industrial building with a total developed area of approx. 8.200 m2 along with the testing of the failure and its repair. Over ten-odd years of operation of the industrial building, its floor was found to develop non-uniform settlement with a maximum depth of approximately 150 mm from the original floor level. The completed survey inspections, geotechnical tests and FEM studies demonstrated that the root cause of these non-uniform settlement events was the foundation of the warehouse floor, built on a subsoil which featured high and long-term deformability. Given the investigated conditions, it was decided to modify the foundation of the new warehouse floor slab by reinforcing the subsoil with drilled micropiling. The calculations completed, test loading of a drilled micropile and on-site inspection of the warehouse flooring in use confirmed that the modification was rational.

Nonhealing orbital floor fracture in a pediatric patient: A unique presentation of pseudo-silent sinus syndrome

ABSTRACTSilent sinus syndrome was first described as spontaneous enophthalmos and hypoglobus associated with subclinical maxillary sinusitis without prior trauma or surgery. This clinical entity has later been described after trauma in which damage to the ostiomeatal complex leads to atelectasis of the maxillary sinus. We report a case of a 14-year-old boy who presented 4 years after sustaining a non-operative orbital floor fracture with enophthalmos and transient diplopia. Computed tomography (CT) demonstrated enlargement in size of the original orbital floor fracture and bilateral maxillary sinus disease. Bilateral chronic sinusitis suggested an anatomical predisposition to sinusitis unrelated to the prior trauma. The authors propose that, in this case, negative pressure in the maxillary sinus and chronic inflammation led to bone resorption and failure of the orbital fracture to heal. This differs from prior reports of silent sinus syndrome in that there was complete resorption of bone of the orbital floor and no decrease in volume of the maxillary sinus given the open communication of the sinus and the orbit, making this a unique presentation of pseudo-silent sinus syndrome in a pediatric patient.

Automatic structural scene digitalization.

In this paper, we present an automatic system for the analysis and labeling of structural scenes, floor plan drawings in Computer-aided Design (CAD) format. The proposed system applies a fusion strategy to detect and recognize various components of CAD floor plans, such as walls, doors, windows and other ambiguous assets. Technically, a general rule-based filter parsing method is fist adopted to extract effective information from the original floor plan. Then, an image-processing based recovery method is employed to correct information extracted in the first step. Our proposed method is fully automatic and real-time. Such analysis system provides high accuracy and is also evaluated on a public website that, on average, archives more than ten thousands effective uses per day and reaches a relatively high satisfaction rate.

Modification history of the Harmakhis Vallis outflow channel, Mars, based on CTX-scale photogeologic mapping and crater count dating

Harmakhis Vallis is one of the four major outflow channel systems (Dao, Niger, Harmakhis, and Reull Valles) that cut the eastern rim region of the Hellas basin, the largest well-preserved impact structure on Mars. The structure of Harmakhis Vallis and the volume of its head depression, as well as earlier dating studies of the region, suggest that the outflow channel formed in the Hesperian period by collapsing when a large amount of subsurface fluid was released. Thus Harmakhis Vallis, as well as the other nearby outflow channels, represents a significant stage of the fluvial activity in the regional history. On the other hand, the outflow channel lies in the Martian mid-latitude zone, where there are several geomorphologic indicators of past and possibly also contemporary ground ice. The floor of Harmakhis also displays evidence of a later-stage ice-related activity, as the outflow channel has been covered by lineated valley fill deposits and debris apron material.The eastern rim region of the Hellas impact basin has been the subject of numerous geologic mapping studies at various scales and based on different imaging data sets. However, Harmakhis Vallis itself has received less attention and the studies on the outflow channel have focused only on limited parts of the outflow channel or on separated different geologic events. In this work, the Harmakhis Vallis floor is mapped and dated from the head depression to the beginning of the terminus based on the Mars Reconnaissance Orbiter’s ConTeXt camera images (CTX; ∼ 6 m/pixel).Our results show that Harmakhis Vallis has been modified by several processes after its formation. Age determinations on the small uncovered parts of the outflow channel, which possibly represent the original floor of Harmakhis, imply that Harmakhis may have experienced fluvial activity only 780–850 ( ± 400–600) Ma ago. The discovered terrace structure instead shows that the on-surface activity of the outflow channel has been periodic. The most significant of the modification processes on Harmakhis Vallis has been the formation of lineated valley fill units. The lineated valley fills now cover the outflow channel almost entirely. They formed not later than ∼ 400 Ma ago based on stratigraphic analyses and crater counts. All the floor units have also been resurfaced several, usually two or three times. The resurfacing ages of the dated units show that the later modification processes have occurred at least on a local scale in the Harmakhis Vallis region, not only inside the outflow channel. This, in turn, may indicate that the processes resulted from a larger-scale change, for example in the local climate or endogenic conditions.

DIJKSTRA-ANT COLONY OPTIMIZATION ALGORITHM FOR SHORTEST AND SAFEST EVACUATION IN HIGH RISE BUILDING

The successfulness of evacuation is defined by the ability of the evacuees to escape from the danger place safely in a short time. The three problems highlighted in this study are evacuees do not know the right route should they take to safe themselves especially in high rise building due to the complexity of the building. Moreover, the provided evacuation map in the building is commonly not showing the shortest and safest path to assist evacuees in choosing the best route. Furthermore, the shortest path algorithm needs additional features to support the directed graph in order to obtain the best result. The objectives of this study are to design and develop the evacuation route via the shortest path algorithm and to evaluate the evacuation route model in high rise building evacuation maps. The methods used are modelling the evacuation route from the original floor plan into 2D floor plan, and then generating the directed graph based on the distance between nodes and coordinate of nodes to generate the shortest and safest path based on the utilisation of Dijkstra’s algorithm and Dijkstra-Ant Colony Optimization (DACO). The results obtained are proven consistent in generating the shortest and safest path with the same distance.

Diagrid Systems for Structural Design of Complex-Shaped Tall Buildings

Today's architectural design trend based on the recognition of pluralism has led to multiple design directions for all building types including tall buildings. This contemporary design trend has produced many complex-shaped tall buildings, such as twisted, tilted, tapered and freeform towers. Among many different structural systems developed for tall buildings, the diagrid system, with its powerful structural rationale and distinguished aesthetic potential, is one of the most widely used systems for today's tall buildings. This paper studies structural performance of diagrid systems employed for complex-shaped tall buildings. Twisted, tilted, tapered and freeform tall buildings are designed with diagrid structures, and their structural performances are investigated. For the twisted diagrid study, the buildings are twisted up to 3 degrees per floor. In the tilted diagrid study, the angles of tilting range from 0 to 13 degrees. The impact of eccentricity is investigated for gravity as well as lateral loads in tilted towers. In the study of tapered diagrid structures, the angles of tapering range from 0 to 3 degrees. In the study of freeform diagrid structures, lateral stiffness of freeform diagrids is evaluated depending on the degree of fluctuation of free form. The freeform floor plans fluctuate from plus/minus 1.5 meter to plus/minus 4.5 meter boundaries of the original square floor plan. Parametric structural models are generated using appropriate computer programs and the models are exported to structural engineering software for design, analyses and comparative studies.

Exhibit Review: The John P. Parker House, Ripley, Ohio

Exhibit ReviewThe John P. Parker House, Ripley, Ohio Martha H. Good The John P. Parker House is on the northern bank of the Ohio River in Ripley Ohio, fifty-two miles east of Cincinnati. Born a slave, Parker bought his freedom in 1845 and settled in Ripley a few years later, molding iron by day and helping fugitive slaves cross the Ohio by night. The original two-story red brick structure at 300 North Front Street was built by Parker in 1849; he lived there with his wife and six children until his death in 1900. When Parker’s widow moved to Cincinnati, the house deteriorated. The roofless shell was near collapse when the John P. Parker Historical Society purchased it and began restoration in the mid-1990s. From May to October Parker House is open to visitors Fridays and Saturdays, 10:00 a.m.–5:00 p.m. and Sundays 1:00 p.m.–5:00 p.m. Admission is $4 for adults, $2 for students five to eighteen, and no charge for children under five. Group tours are available year-round by calling 937-392-4188. Visitors enter through the side entrance, where there is a small gift shop and elevator to the second floor. From there, they enter the front hall and parlor, which is an orientation room. Docent Dewey Scott provides an engaging chronology of John P. Parker’s life as a slave, abolitionist, inventor, entrepreneur, husband, and father. Behind the front parlor is a larger room displaying powerful paintings commissioned for Parker House. Because there are no known portraits or photos of Parker, the artists used their imagination to create his image. Louisville artist Mark Priest created four canvases depicting the life of Parker from [End Page 88] slave boy in Virginia to his freedom in Alabama at eighteen; each is based upon and accompanied by quotes from Parker’s memoir, His Promised Land. Click for larger view View full resolution John P. Parker and his family lived in this house for more than fifty years. (Source: Photo by Martha H. Good) On the opposite wall, a replica of the boat he used to carry runaway slaves across the Ohio is filled with seven paintings showing scenes of fugitive slaves’ journey by Ripley artist Allen Schwartz. Above the boat is a three-panel painting showing Ripley in pink while a giant Parker, with feet on both sides of the Ohio, stoops down, his hands guiding a small boat of escaping slaves across the river. The second-floor front room is outfitted as a bedroom with period furniture and accessories. But visitors are reminded of the authenticity of the site by a sign painted on the original floor telling them that they are standing where Parker once stood. All four walls of the rear second-floor room are covered with additional information about Parker and events of his time. One wall documents his transition from slave child in Virginia to freedman in Ripley. Another wall provides information about the Underground Railroad, the Black Brigade, [End Page 89] the United States Colored Troops, and post–Civil War amendments to the Constitution. A third wall details Parker’s three patents and the recognition he received for them. There are models of his inventions in display cases in the middle of the room. The fourth wall conveys “The Parker Legacy,” including how Parker’s memoir was discovered and published, the formation of the Parker Historical Society, the Parker House restoration, and the individuals and groups who helped create this charming museum. This compact museum is a delightful place to visit and it is an easy daytrip from Cincinnati. A visit to Parker House can be combined with a tour of the John Rankin House, high on a hill just minutes from Parker House. In addition, the route from Cincinnati to Ripley along the Ohio River Scenic Byway (Route 52), passes by Ulysses S. Grant’s birthplace in Point Pleasant and through New Richmond, another charming Ohio River town well worth a visit. [End Page 90] Martha H. Good Friends of Harriet Beecher Stowe House Copyright © 2016 The Kent State University Press

Vertical safe separation distance between openings in multi-storey buildings having a fire resistant spandrel

A novel comprehensive methodology is presented for the determination of the vertical separation distance between floor glazing openings in buildings having a fire resistant non-flammable spandrel. The spandrel height is specified by requiring that the heat flux is less than a critical heat flux for glazing failure at the base of the opening of the floor above the floor of fire origin. For a specified room, opening geometries and fuel type, the heat flux at the base of this opening is calculated by using correlations for the flame height and heat flux distribution of the facade flames for under ventilated fire conditions in the compartment of fire origin. As the compartment opening increases a transition occurs from under ventilated to over ventilated conditions reducing the facade fire spread hazard. The methodology and results can also be applied for wooden and lightweight facade walls to predict fire spread behavior on the wall and towards the openings to floors above the floor of fire origin. © Owned by the authors, published by EDP Sciences, 2016 Language: en

Graft Remodeling following Transcrestal Sinus Floor Elevation via the Gel-Pressure Technique (GPT) and Pasteous Nano-Crystalline Hydroxyapatite Bone Substitute

Bone grafting of the maxillary sinus is attempted to compensate for sinus pneumatization and permit reliable insertion of endosseous dental implants for prosthetic rehabilitation. The aim of the present clinical investigation was to study bone regeneration four months after transcrestal sinus floor elevation via the Gel-Pressure Technique (GPT) and application of pasteous nano-crystalline hydroxyapatite bone substitute. A total of 25 patients with deficient alveolar ridges in the posterior maxilla (mean residual bone height: 4.7 ± 1.8 mm) were subjected to 32 flapless transcrestal sinus floor augmentations and simultaneous insertion of 40 implants. Sinus membrane elevation height averaged 11.2 ± 2.7 mm and minimal vertical graft resorption of 0.1 mm was observed after four months. Radiographic bone density averaged 460 Hounsfield units in regions adjacent to the native jawbone (1 to 7 mm distance), while reduction of bone density by −7.2%, −11.3%, −14.8%, −19.6% and −22.7% was recorded in more apical regions of 8, 9, 10, 11, and ≥12 mm distance to the original sinus floor, respectively. The results suggest that graft remodeling is completed up to a distance of 7 mm within a healing period of four months after sinus augmentation using nano-crystalline hydroxyapatite bone substitute material.

Modal Frequencies of a Reinforced Timber-Concrete Composite Floor: Testing and Modeling

AbstractThe reinforcement of a timber floor with a concrete layer properly connected to produce a composite system represents not only an improvement in the stiffness but also a foreseeable change in the modal frequencies of the floor. In order to assess that change, a typical timber floor, which was subsequently reinforced with a concrete layer to produce a composite, was tested at both stages in the research reported in this paper. Additionally, composite beams taken from the original floor were also tested. The results showed a significant decrease (44%) in the fundamental frequency after the reinforcement. In order to obtain the mode shapes and frequencies of the floor, finite-element (FE) models of the floors and beams were created. The FE models accurately matched the experimental results. Having validated the model, a parametric study was carried out to compare the results provided by the proposed FE model with a numerical model from the bibliography and to understand the influence of the most rele...

Modeling and simulation of pedestrian evacuation from a single-exit classroom based on experimental features

It is of fundamental importance to investigate the evacuation process from a room with obstacles. The typical case is the evacuation of students from a classroom. Based on evacuation experiments from a classroom, the essential features of evacuee are concluded. In the original floor field model, the dynamic floor field is introduced in order to reflect the interaction among pedestrians. A pedestrian may follow the virtual trace of another one in front. The static floor field does not consider the influence of pedestrians. In this paper, the original dynamic floor field is ignored. These desks and chairs are treated as impassable and passable static obstacles, respectively. The static and passible obstacles, such as chairs, lead to the delay of movement of pedestrians. Furthermore, pedestrians are regarded as movable obstacles. The effect of static obstacles on floor field does not change with time. However, the effect of movable obstacles on floor field is dynamic. Therefore, the whole floor field is updated dynamically according to the movement of crowd. Pedestrians may try to find another uncongested path or exit when they find the crowd in front. It provides a better description of the influence of downstream congestions on upstream crowd. The cellular automaton model based on the dynamic floor field is used to investigate the evacuation process in the case of four layouts and three exit widths. The spatial distributions of evacuation time in different conditions and also the average and maximum evacuation times are obtained. Numerical simulations reproduce the evacuation process observed in the experiment quite well. The evacuation time depends on arrangement of these desks and the exit width. For a given layout, the smaller exit leads to longer evacuation time. It is found that the evacuation time does not decrease monotonically with increasing the number of aisles, which depends on the width of aisle as well. When the aisle is not wide enough, the conflict of pedestrians from both sides reduces the efficiency of evacuation. It is helpful for coping with crowd evacuation with an aisle close to the exit side of the wall. The reasons of the differences between experimental and simulation results are also discussed in more detail.

Automotive Floor Sound Package Design Using Statistical Energy Analysis

An increasing demand for vehicle noise control has been proposed and at the same time, vehicle weight and fuel economy have become critical for the automotive industry. The methodology of statistical energy analysis (SEA) is used to balance both light weight and high noise insulation performance. In this paper, the floor system which is one of the major paths for vehicle interior noise is studied with two sound package systems, the original floor insulation system and the lightweight one. The vehicle floor system is modeled by SEA and its transmission loss (TL) is analyzed. The results show that under certain sound package coverage, the TL of the floor system with the lightweight sound package is a little larger than the TL with the lightweight one. However, the lightweight sound package system has better absorption property and the advantage of weight reduction. Finally, in order to get the better TL, the sound package design is performed.