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This article focuses on testing and investigating further development needs for LiDARs in self-driving cars in adverse weather. The article compares two different LiDARs (Ibeo Lux and Velodyne PUCK), which both use the 905 nm wavelengths, which are used in more than 95% of currently available LiDARs. The performance was tested and estimated in stabilized fog conditions at Cerema fog chamber facilities. This provides a good basis for repeating the same validation procedure multiple times and ensuring the right development decisions. However, performance of the LiDARs suffers when the weather conditions become adverse and visibility range decreases. A 50% reduction in target detection performance was observed over the exhaustive tests. Therefore, changing to higher wavelengths (1550 nm) was considered using redesigned 'pre-prototype LiDAR'. The preliminary results indicate that there is no reason to not use 1550 nm wavelength, which due to eye safety regulations gives an opportunity to use 20 times more power compared to the traditional 905 nm. In order to clarify the expected benefits, additional feasibility studies are still needed.

With an increased awareness of sustainability issues, natural ventilation has become an elegant method for reducing the costs and environmental effects of the energy that is used to maintain comfortable indoor air quality rather than using mechanical ventilation. The windows in many industrial buildings are continuously open to exhaust pollutants and intake fresh air. Though windows are functional and efficient for natural ventilation, rainwater is able to penetrate through the windows during wind-driven rain. For industries in which the moisture content affects the quality of the product, the intrusion of a large amount of rainwater through windows must be prevented without compromising the effective ventilation. The aim of this research is to determine an innovative design for windows to accomplish the optimum of high ventilation and low rain penetration. For this purpose, windows are variously innovated and tested in full-scale measurements, reduced-scale wind-tunnel measurements and computational fluid dynamics (CFD). An artificial rain and wind velocity to mimic the average of the maximum values in Korea are created. The maximum reduction in rain penetration of over 98% compared to basic 90 degrees open windows is attained with only a 4%-9% decrement of ventilation efficiency in the two recommended designs.

A humidade e uma das principais causas de ocorrencia de anomalias em alvenarias historicas. Deste modo, o controle dos movimentos da humidade em paredes macicas de alvenaria e um instrumento fundamental para a melhoria da durabilidade destas. A investigacao e a experiencia pratica identificaram ja varias das causas que podem influenciar os problemas de permeabilidade em alvenarias. O presente artigo e dedicado aos aspectos materiais relacionados com a penetracao de agua em paredes historicas em alvenaria de barro cozido, construidas com tijolos de absorcao moderada a alta, assentes com argamassas de cal; discutem-se, nomeadamente, a ocorrencia e influencia de parâmetros como a porosidade dos tijolos, infiltracoes nas interfaces e resistencias das juntas de argamassa. Subsequentemente, sao apresentados resultados quantitativos de testes que avaliam os efeitos destes parâmetros na ocorrencia de infiltracoes em paredes macicas de diferentes espessuras. Os resultados das investigacoes permitem apontar algumas recomendacoes as quais recorrer no caso de reparacoes em alvenarias historicas macicas. Finalmente, e ainda dedicada alguma atencao a influencia da mao-de-obra na permeabilidade deste tipo de paredes.

Dwellings can be designed, built and operated with a proper balance of humidity levels, ventilation, and energy use. Condensation damage is examined, sources of moisture are identified, the building envelope is discussed, and ventilation practices are suggested. Individual papers are separately indexed., Building Science Insight '83, Humidity, condensation and ventilation in houses, October 1983, St. John's, Halifax, Moncton, Canada

Moisture is a major source of damage in historic solid masonry. Therefore, control of moisture movement in masonry is instrumental to the durability of masonry buildings. From research and practical experience it is known that many factors may play a role regarding permeability problems in masonry. This paper is focused on materials aspects regarding water penetration in historic fired clay masonry walls, constructed with moderate-to-high absorption bricks and lime mortars; the occurrence and influence of parameters such as brick porosity, interface leakage and mortar joint resistance are discussed. Subsequently, quantitative tests results show the effects of these parameters on leakage of solid walls of different thicknesses. The results of the investigations lead to a number of recommendations to be used in case of repair of historic solid masonry. Finally, attention is paid to the influence of workmanship on the permeability behaviour of historic solid walls.

Rakenteiden suurimmat rakenteiden kosteusriskit liittyvät ulkopuolisen kosteuden tunkeutumiseen rakenteen sisään ja rakenteen rajalliseen kuivumiskykyyn verrattuna mahdollisiin kosteuskuormiin rakentamisen tai käytön aikana. Rakenteiden kuivumiskyvyn kokeellinen määritysmenetelmä ja siihen liittyvä laitteisto tuotteistettiin rakenteiden ja niiden tuulensuojakerrosten kuivumistilanteen aikaisten kosteudensiirto-ominaisuuksien tutkimus- ja testauskäyttöön soveltuvaksi. Koelaitteistolla voidaan tutkia ja vertailla yhtä aikaa 20 rinnakkaista rakennetta tyypillistä kuivumistilannetta vastaavissa oloissa. Menetelmällä voidaan määrittää mm. kosteuden tiivistymisen ja jäätymisen vaikutus tuulensuojan kykyyn läpäistä vesihöyryn diffuusiota. Rakenteisiin asetetun alkukosteuden kuivumista seurataan ja tuloksena saadaan tutkittujen rakenteiden kuivumiskyky tarkasteluoloissa ja lisäksi voidaan määrittää tuulensuojakerroksen vesihöyryn tehollinen läpäisevyys kuivumistilanteessa. Sadeveden tunkeutumisriskin määritystä kokeiltiin laitteistolla, joka normaalin sadekoelaitteistosta poiketen tuottaa tuulen paineen tutkittavan rakenteen ulkopinnalle, eikä vain paine-eroa rakenteen yli. Menetelmän etuna on ulkoverhouksen sateenpitävyyden testaaminen mahdollisimman hyvin todellisia tuulen tuottamia painesuhteita vastaavissa oloissa, jolloin paikallisen painegradientin vaikutus rakennekerroksen tai -detaljin sateenpitävyyteen tulee otettua huomioon. Hyvä kuivumiskyky ja sadeveden tunkeutumisen estäminen parantavat rakenteen vikasietoisuutta ja kosteusriskien hallintaa. Jos rakenteen uloimman kerroksen diffuusiovastus on suuri, voidaan rakenteen kuivumiskykyä olennaisesti parantaa rajoitetulla tuuletuksella tämän kerroksen läpi. Suhteellisen pienikin tuuletusilmavirtaus kasvattaa tällaisen rakenteen kuivumiskykyä huomattavasti ilman, että sen lämpötekninen toiminta heikkenee.

Rakenteiden suurimmat rakenteiden kosteusriskit liittyvät ulkopuolisen kosteuden tunkeutumiseen rakenteen sisään ja rakenteen rajalliseen kuivumiskykyyn verrattuna mahdollisiin kosteuskuormiin rakentamisen tai käytön aikana. Rakenteiden kuivumiskyvyn kokeellinen määritysmenetelmä ja siihen liittyvä laitteisto tuotteistettiin rakenteiden ja niiden tuulensuojakerrosten kuivumistilanteen aikaisten kosteudensiirto-ominaisuuksien tutkimus- ja testauskäyttöön soveltuvaksi. Koelaitteistolla voidaan tutkia ja vertailla yhtä aikaa 20 rinnakkaista rakennetta tyypillistä kuivumistilannetta vastaavissa oloissa. Menetelmällä voidaan määrittää mm. kosteuden tiivistymisen ja jäätymisen vaikutus tuulensuojan kykyyn läpäistä vesihöyryn diffuusiota. Rakenteisiin asetetun alkukosteuden kuivumista seurataan ja tuloksena saadaan tutkittujen rakenteiden kuivumiskyky tarkasteluoloissa ja lisäksi voidaan määrittää tuulensuojakerroksen vesihöyryn tehollinen läpäisevyys kuivumistilanteessa. Sadeveden tunkeutumisriskin määritystä kokeiltiin laitteistolla, joka normaalin sadekoelaitteistosta poiketen tuottaa tuulen paineen tutkittavan rakenteen ulkopinnalle, eikä vain paine-eroa rakenteen yli. Menetelmän etuna on ulkoverhouksen sateenpitävyyden testaaminen mahdollisimman hyvin todellisia tuulen tuottamia painesuhteita vastaavissa oloissa, jolloin paikallisen painegradientin vaikutus rakennekerroksen tai -detaljin sateenpitävyyteen tulee otettua huomioon. Hyvä kuivumiskyky ja sadeveden tunkeutumisen estäminen parantavat rakenteen vikasietoisuutta ja kosteusriskien hallintaa. Jos rakenteen uloimman kerroksen diffuusiovastus on suuri, voidaan rakenteen kuivumiskykyä olennaisesti parantaa rajoitetulla tuuletuksella tämän kerroksen läpi. Suhteellisen pienikin tuuletusilmavirtaus kasvattaa tällaisen rakenteen kuivumiskykyä huomattavasti ilman, että sen lämpötekninen toiminta heikkenee.

Nous décrivons brièvement certains éléments relatifs à la limitation de la pénétration de la pluie dans les murs extérieurs : l'indice directionnel de pluie chassée et l'effet de la taille des gouttes de pluie sur le mouillage des façades.

Zweischaliges Sichtmauerwerk ist in Norddeutschland eine traditionelle Wandkonstruktion und hat sich dort vor allem bei starker Schlagregenbeanspruchung bewaehrt: Die Vormauerschale uebernimmt den Regenschutz und die Hintermauerschale die konstruktiv-tragende und daemmende Funktion, letzteres meist in Verbindung mit einer zusaetzlichen Waermedaemmung in der Zwischenschicht. Wird die Vormauerschale aber verputzt, dann koennen Putzrisse auftreten, die den Regnschutz und das Aussehen beeintraechtigen. Dies wird anhand von zwei Schadensfaellen erlaeutert.

The rainscreen concept was first referenced as a means of rain penetration control in the 1940's. Later researchers applied physics principles to develop the 'pressure equalized rainscreen principle' as it is known today. Through the development process a selection of terminology has been used to describe the concept which uses a rainscreen to control rain penetration due to the kinetic energy of raindrops. 'Cavity wall', 'open rainscreen wall', 'rainscreen principle' and. 'two stage weather tightness' are key words commonly encountered in literature addressing the control of rain penetration. In most cases, the concepts also addressed the control of rain penetration by other forces such as gravity, surface tension and capillarity. Some specifically addressed the control of rain penetration by wind induced air pressure difference across the wall system. The fundamental differences between these wall concepts are never clearly described. Consequently, when the rainscreen concept is applied to wall design, these key words are used interchangeably and it is difficult to know what is really meant when a wall is required to be designed according to, for example, the 'rainscreen principle'., Proceedings, Sixth Conference on Building Science and Technology: 05 March 1992, Toronto, Ont. Canada

Silicone water-repellents greatly reduce the water-absorbing properties of many masonry materials, therefore they have been extensively used to treat walls for a variety of faults resulting from their wetting by rain, including water penetration, efflorescence, and decay. The nature of silicones and their action when applied to masonry materials are considered, along with their effectiveness in overcoming certain rain-related faults of masonry walls.

This note documents wall moisture problems in two buildings located in Atlantic Canada. A brief description of the construction details is supplemented by photographs taken during cladding removal which record the nature and extent of rain-induced damage.

The building envelope provides the separation between inside and outside environments and controls flows of mass and energy. Rehabilitation of buildings usually involves new interior conditions that will normally impose a more severe service environment for the building envelope than existed in the original building. The walls and roofs have to be designed to maintain the separation of the two dissimilar environments without deterioration and this should take precedence over restoration considerations. The paper deals with the upgrading of walls and roofs to increase airtightness, reduce rain penetration and conserve energy use. It discusses the effect of insulation and the location of insulation on the envelope performance and the types of wall and roof modification that are possible. Exterior cladding and insulation on the exterior of walls, controlled buffer spaces for walls, and exposed insulation in the protected membrane mode for roofs is considered., Proceedings, Second Canadian Building Congress: 15 October 1979, Toronto, Ontario, Canada

This paper focusses on the control of air leakage and its importance to preventing condensation in or on the walls and to minimizing rain penetration problems., Aussi disponible en francais: Les murs en panneaux préfabriqués, Building Science Insight 1982: Exterior Walls: Understanding the Problems: 1982-10

Cet article analyse la nature des exigences vis à vis des fenêtres de trois points de vue différents : en tant que système, en tant que partie de l'enveloppe du bâtiment et en tant qu'élément de l'environnement intérieur. Il donne également un aperçu de l'éventail actuel de fenêtres et de composants de fenêtres disponibles sur le marché., Regard 88 sur la science du bâtiment - Les fenêtres : performance et technologie de pointe, 1988, Différentes villes canadiennes, Collection: Compte rendu (Conseil national de recherches Canada. Institut de recherche en construction); nº 15

This report reviews present building techniques related to the installation of flashing and sheathing paper around window openings and shows how maintaining the simple principles related to water shedding can help eliminate the potential for water leakage between the window frame and the rough opening. A method is proposed to prevent water penetration below the window sill.

The focus of current research at DBR is to determine what factors contribute to the operation of the rain screen and their importance in relation to each other. As a preliminary step to this research, a literature survey was done to determine the extent of research already completed on the open rain screen, especially on the phenomenon of pressure equalization. This bibliography is the result of that survey.

Good design detail is necessary for the control of rain penetration of masonry walls. The development of an effective design detail requires understanding of the environment to which the proposed building will be exposed and the properties of the materials that will be used in its construction. Architectural detail that will direct water away from vulnerable areas is desirable. The effects of exposure on masonry, cracking, control joints, anchorage, flashing and weep holes are discussed.

The curtain wall system has evolved rapidly over the past two decades especially with respect to environmental separation. Early systems frequently presented rain penetration problems, were subject to build-up of icicles or condensation and suffered from the failure of glazing seals. Most of these difficulties have been overcome but some difficulty remains at the joints between the curtain wall system and other parts of the building. A definition of curtain wall is provided and the system is described in terms of how it responds to wall design requirements such as airtightness, thermal resistance, vapour resistance, rain protection, and accommodation of structural and thermal movement. Details of junctions at parapets, corners, grade, masonry precast siding, soffits and sloped walls/roofs are presented and discussed.

Total moisture input in a house is a combination of that contributed by the occupant and his activities, and from a number of sources such as construction moisture, the seasonal storage effect, basements or crawlspaces and rain- soaked walls., Building Science Insight 1983: Humidity, Condensation and Ventilation in Houses: 1983-10, St. John's, Halifax, Moncton, etc.

The open rain screen principle presupposes that if the pressure difference across the vented cladding of an exterior wall system is zero, then one of the factors that drives rain into the building envelope is inhibited. Laboratory measurements of the time taken for pressures to equalize across the glass cladding of a metal and glass curtain wall unit and the subsequent transient load on it are presented and discussed. Aspects needing further consideration are also identified., Canadian Society for Civil Engineering Centennial Conference Proceedings : La Société Canadienne de génie civil conférence centenaire compte rendus: 19 May 1987, Montreal, Que., Canada

Good workmanship in masonry construction is difficult to define because of the many variables involved. A knowledge of the philosophy behind the design and of the properties of the materials selected for the project will help the mason achieve a standard of workmanship that will result in a masonry wall capable of resisting rain penetration.

In the fall of 1987 Suter Keller Inc. (SKI) was retained by the Ottawa-Carleton Regional Housing Authority to carry out an investigation of the deteriorating exterior loadbearing masonry walls at a building complex constructed in Ottawa in 1973-74. The main objectives of the work were to determine the cause or causes of deterioration and to propose remedial work options. SKI in turn engaged the services of the Institute for Research in Construction (IRC) to carry out physical testing of brick samples for a durability assessment, monitor moisture/temperature conditions of an exterior wall, and provide input into the overall assessment of building envelope deterioration., Proceedings of the Fifth Canadian Masonry Symposium: 05 June 1989, Victoria, B.C., Canada

Wind pressure differences are measured across the rain screen and across the air barrier assembly of precast open rain screen wall panels. Twelve panels are instrumented mostly on the west, north, and east walls of the 24th floor of a 27-story office building in downtown Montreal. 32 channels were scanned at 30 times per second to allow reasonable resolution of peak gusts. However, some doubt remains about their spatial extent, as each 3.6 X 2.9 m (11. 8 X 9.5 ft) panel had only one external tap. The maximum load measured on the rain screen in one year of continuous monitoring was 285 Pa (6 psf), of duration 1 second. The largest pressure difference across an entire panel of the building envelope never coincided with peak pressure differences on the rain screen. However, maxima due to wind only, across windward panels, ranged from 400-475 Pa (8.4-9. 9 psf). Pressure differences across the air barrier assembly of wall panels included stack and heating, ventilating, and air conditioning (HVAC) effects of up to 150 Pa (3.1 psf) when outside temperatures dropped to -20 degrees C (-4 degrees F).

This paper examines the nature of the requirements for windows from three points of view: as a system of elements, as part of the building envelope, and as part of the indoor environment. It also describes briefly the current array of windows and window components on the market., Building Science Insight '88, Fall 1988, cities across Canada, Series: Proceedings (National Research Council of Canada. Institute for Research in Construction)

Les produits hydrofuges de silicone réduisent de beaucoup les propriétés d'absorption de l'eau de plusieurs matériaux de maçonnerie; on les emploie donc souvent pour des murs ayant subi des dégâts dus à l'humidification causée par la pluie, y compris la pénétration de l'eau, l'efflorescence et la décomposition. L'auteur étudie la nature des silicones et leur action lorsqu'on les ajoute aux matériaux de maçonnerie, ainsi que leur efficacité contre certains effets de la pluie sur les murs de maçonnerie.

In brief, the rules for building watertight masonry are given in this paper as follows: 1. All the joints should be grouted completely; each brick should be surrounded by an unbroken watertight layer of mortar. 2. The brick should have a water suction of between 10 and 30 gm. when one of its flat sides is immersed 3 mm. in water for one minute. More porous facing bricks must be soaked. 3. A mortar, which has a high cement content and which is mixed in a mixer at the building site, should be used. A suitable mixture, in parts by volume, is as follows: 1 cement + 1 lime + 6-7 sand or 1 cement + 1/2 lime + 4.5-5 sand.

The evolution of roofing systems has been largely influenced by the requirements for control of rain penetration, but in modern roof design other sources and effects of moisture must be considered. This Digest discusses the principles involved and their application to conventional designs.

High-absorption brick were treated with a water-soluble silicone before they were combined with mortar into brick masonry. The resistance of the masonry to moisture penetration was much improved compared with that in which untreated brick or brick soaked in water had been used. The silicone pretreatment in some cases increased, in others decreased, the strength of bond in direct tension between brick and mortar compared with that obtained from the brick used dry. Outdoor exposure of brickwork samples demonstrated that silicone pretreatment of bricks resulted in cleaner-appearing brick masonry.

La plupart des problèmes présentés par les toitures peuvent être éliminés ou tout au moins minimisés par l'obéissance aux principes suivants lors de leur conception: -- 1. Étudier toutes les exigences, tant individuellement qu'en groupe, et ne pas négliger l'une au bénéfice de l'autre sans en connaî tre les conséquences. -- 2. Concevoir la toiture de facon que les mouvements et les affaissements structuraux soient réduits au minimum, économiquement, et tenir compte pour les éléments associés des mouvements qui se produiront inévitablement. -- 3. Avoir une bonne connaissance du milieu environnant dans lequel chaque matériau travaillera et de son action sur le matériau. -- 4. Faciliter le travail de chaque élément par un choix judicieux de leur nature et de leur emplacement dans la toiture.

Cavity walls afford complete protection against rain penetration. The cavity wall must have a gutter at its base to collect leakage water and drains to direct water out of it. The two parts of the wall must be anchored together with metal ties that are corrosion resistant and adequately strong. The wall must have a cavity free of mortar or other material that may form a water bridge across it.

Large bricklayer-constructed wallettes have been used by many laboratories in studies of the problem of moisture penetration of brick masonry was developed which makes use of a small panel of bricks masonry. Although they reproduce actual conditions of construction of brick masonry, there are disadvantages to their use, such as costs, space requirements, and possible variation in workmanship or technique of bricklaying. A method for investigating factors in the problem of moisture penetration of brick masonry was developed which makes use of a small panel of bricks and mortar. The same panels used in moisture penetration tests can also be tested for strength of bond in direct tension between brick and mortar. The method of panel construction and the apparatus for tests of moisture penetration and bond strength are described.

L'auteur décrit quelques difficultés découlant de la disposition habituelle des éléments préfabriqués en béton dans les murs. Il en explique les causes profondes et démontre qu'elles sont reliées à utilisation d'un concept erroné lors de la conception des murs., Digeste de la construction au Canada, CBD-93F

The uses and limitations of the methods currently available for evaluating resistance to rain-leakage are discussed in this paper, as well as the studies undertaken by DBR/NRC to obtain information that may improve the prediction of rain- leakage performance., Reprinted from the proceedings of the 5th CIB Congress: Research into Practice: The Challenge of Application, p. 485-487., Research into Practice: The Challenge of Application. 5th CIB Congress, June 1971, Versailles, France

It is only recently that scientific studies have been undertaken to explain the mechanisms of rain penetration. Through better understanding of these mechanisms it should be possible to design and construct walls from which the problem is virtually eliminated.

Some problems that have developed in walls which incorporate precast panels in the conventional manner are described. The underlying causes are explained and shown to be linked to a basically faulty concept of wall design.

Structural neoprene gaskets are widely used in the North American construction industry. They perform relatively well, but some problems do occur, such as rain penetration, air leakage through pre-sealed glazing units, the fracture of glazing units and failure to retain the glass against wind load. The retention of glass by the gasket and the weathertightness of joints depend on the equalization of air pressure between the glass, gasket and frame., Symposium on Weathertight Joints for Walls: 1967-09, Oslo, Norway

This study was undertaken to simulate in the laboratory premature cracking and flaking of exterior oil house paint on wood as they occur in practice in order to support a proposed mechanism of breakdown. Samples of primer and finish paints identical to those that had failed in the field and laboratory paints of similar composition were applied on wood and subjected to three different wetting-and- radiation-drying cycles. Cracking and flaking induced by Cycle I closely resembled those in the field. This supports the view that the main cause of the field failure was the repeated influx of rain water through the paint film.

The present study is based on artificial rain tests carried out at the experimental station of the Centre Scientifique et Technique du Bâtiment at Champs-sur-Marne. These tests had the dual purpose of determining the possibilities of utilizing certain materials and of studying various waterproofing methods., Translation of "Résistance à l'eau de pluie des matériaux poreux", Cahiers du Centre Scientifique et Technique de Bâtiment, Pub. Trim. 19, Cahier, 178, 1953. 11 p.

Large brick masonry panels of several types of bricks and two mortars were tested for moisture penetration by spraying water on one face and maintaining an air-pressure difference across the panel to simulate wind and rain. The resistance of the panels to moisture penetration varied greatly and depended on the properties of the brick and mortar in combination. Leakage occurred at the brick-mortar interface, and in some cases through the bricks. Information on the influence of air pressure on leakage and on the influence of wall thickness on leakage was obtained. Working properties of the materials affected the bricklayer' s technique of constructing the panels. The effect on moisture penetration of weathering panels by outdoor exposure was also studied.

Ce n'est que récemment que des études scientifiques ont été entreprises pour expliquer les mécanismes de la pénétration de la pluie. Grâce à une meilleure compréhension de ces mécanismes il devrait être possible de concevoir et de construire des murs capables de résister à la pénétration de la pluie.

This paper identifies the various sources of rain leakage in windows, and offers design suggestions for minimizing this leakage. Examples are given to illustrate the features that can be incorporated in window design to improve rain-leakage resistance. The design features were evolved from rain- leakage tests performed on a number of modified proprietary windows at the Division of Building Research.