Probabilistic estimation of residential air exchange rates for population-based human exposure modeling

Science.gov (United States)

Residential air exchange rates (AERs) are a key determinant in the infiltration of ambient air pollution indoors. Population-based human exposure models using probabilistic approaches to estimate personal exposure to air pollutants have relied on input distributions from AER meas...

Personal exposures to NO2 in the EXPOLIS-study: relation to residential indoor, outdoor and workplace concentrations in Basel, Helsinki and Prague

International Nuclear Information System (INIS)

Kousa, A.; Rotko, T.; Alm, S.; Monn, C.

2001-01-01

Personal exposures, residential indoor, outdoor and workplace levels of nitrogen dioxide (NO 2 ) were measured for 262 urban adult (25-55 years) participants in three EXPOLIS centres (Basel, Switzerland; Helsinki, Finland; and Prague, Czech Republic) using passive samplers for 48-h sampling periods during 1996-1997. The average residential outdoor and indoor NO 2 levels were lowest in Helsinki (24 ± 12 and 18 ± 11 μgm -3 , respectively), highest in Prague (61 ± 20 and 43 ± 23μgm -3 ), with Basel in between (36 ± 13 and 27± 13μgm -3 ). Average workplace NO 2 levels, however, were highest in Basel (36 ± 24μgm -3 ), lowest in Helsinki (27 ± 15μgm -3 ), with Prague in between (30 ± 18μgm -3 ). A time-weighted microenvironmental exposure model explained 74% of the personal exposure variation in all centre and in average 88% of the exposures. Log-linear regression models, using residential outdoor measurements (fixed site monitoring) combined with residential and work characteristics (i.e. work location, using gas appliances and keeping windows open), explained 48% (37%) of the personal NO 2 exposure variation. Regression models based on ambient fixed site concentrations alone explained only 11-19% of personal NO 2 exposure variation. Thus, ambient fixed site monitoring alone was a poor predictor for personal NO 2 exposure variation, but adding personal questionnaire information can significantly improve the predicting power. (Author)

Human Thermal Comfort In Residential House Buildings Of Jimma Town Southwest Ethiopia.

Directory of Open Access Journals (Sweden)

Chali Yadeta

2015-08-01

Full Text Available Indoor human thermal comfort is an important factor in indoor air quality assessment. Thermal comfort affects human health work efficiency and overall wellbeing. Thermal discomfort in indoors lowers the emotional and physical health of the occupants. This paper targets to explore human thermal comfort in residential house buildings of Jimma town and state some possible mechanisms to improve the existing thermal discomfort in large number the houses. For the study 303 structured questionnaires were distributed to the residential houses in thirteen places of the town based on predetermined criteria. The study reveals that human thermal discomfort in residential houses Jimma town are mainly from poor architectural design and improper use of heat generating appliances in indoors. The uses architectural design that suites the present climatic conditions and use of materials that facilitates ventilations will enhance the realization of the required human thermal comfort in residential houses of the study area.

Reducing indoor residential exposures to outdoor pollutants

Energy Technology Data Exchange (ETDEWEB)

Sherman, Max H.; Matson, Nance E.

2003-07-01

The basic strategy for providing indoor air quality in residences is to dilute indoor sources with outdoor air. This strategy assumes that the outdoor air does not have pollutants at harmful levels or that the outdoor air is, at least, less polluted than the indoor air. When this is not the case, different strategies need to be employed to ensure adequate air quality in the indoor environment. These strategies include ventilation systems, filtration and other measures. These strategies can be used for several types of outdoor pollution, including smog, particulates and toxic air pollutants. This report reviews the impacts that typical outdoor air pollutants can have on the indoor environment and provides design and operational guidance for mitigating them. Poor quality air cannot be used for diluting indoor contaminants, but more generally it can become an indoor contaminant itself. This paper discusses strategies that use the building as protection against potentially hazardous outdoor pollutants, including widespread pollutants, accidental events, and potential attacks.

LIFETIME LUNG CANCER RISKS ASSOCIATED WITH INDOOR RADON EXPOSURE BASED ON VARIOUS RADON RISK MODELS FOR CANADIAN POPULATION.

Science.gov (United States)

Chen, Jing

2017-04-01

This study calculates and compares the lifetime lung cancer risks associated with indoor radon exposure based on well-known risk models in the literature; two risk models are from joint studies among miners and the other three models were developed from pooling studies on residential radon exposure from China, Europe and North America respectively. The aim of this article is to make clear that the various models are mathematical descriptions of epidemiologically observed real risks in different environmental settings. The risk from exposure to indoor radon is real and it is normal that variations could exist among different risk models even when they were applied to the same dataset. The results show that lifetime risk estimates vary significantly between the various risk models considered here: the model based on the European residential data provides the lowest risk estimates, while models based on the European miners and Chinese residential pooling with complete dosimetry give the highest values. The lifetime risk estimates based on the EPA/BEIR-VI model lie within this range and agree reasonably well with the averages of risk estimates from the five risk models considered in this study. © Crown copyright 2016.

A study on subjective preference to daylit residential indoor environment using conjoint analysis

Energy Technology Data Exchange (ETDEWEB)

Cheung, H.D.; Chung, T.M. [Department of Building Services Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)

2008-12-15

This paper reports a study of the subjective preference to daylit indoor environment of a residential room using conjoint analysis, which is a highly reputable method used to analyze the mutual relationships among different attributes. Seven influential attributes were selected in the view of daylight performance assessment. They include 'general brightness', 'desktop brightness', 'perceived glare', 'sunlight penetration', 'quality of view', 'user friendliness of shading control' and 'impact on energy'. Each of them has two levels. A total of eight combinations (profiles) of attributes with various levels were established by adopting fractional factorial design. Subjects were asked to rank-order the eight profiles according to their preference in terms of daylit environment of a residential room. The study aims at finding out the relative impact of the seven selected attributes to the overall daylight performance and seeking an organized assessment method for a residential daylit environment. Conjoint analysis found that the seven attributes have importance level in the order of 'quality of view', 'general brightness', 'impact on energy', 'user friendliness of shading control', 'perceived glare', 'desktop brightness' and 'sunlight penetration'. (author)

Controlling indoor climate. Passive cooling of residential buildings in hot-humid climates in China

Energy Technology Data Exchange (ETDEWEB)

Zhiwu, Wang

1996-10-01

Overheating is a paramount problem in residential buildings in hot and humid climates in China during summer. This study aims to deal with the overheating problem and the problem of poor air quality in dwellings. The main objective is to improve indoor thermal conditions by passive cooling approaches, climatisation techniques in buildings without auxiliary cooling from air conditioning equipment. This thesis focuses on the study of cross-ventilation in apartments, which is one of the most effective ways of natural cooling in a hot humid climate, but is also one of the least understood parts in controlling indoor climate. The Computational Fluid Dynamics (CFD) technique is used, which is a new approach, since cross-ventilation studies have been conventionally made by wind tunnel tests. The validations of the CFD technique are examined by a comparison between wind tunnel tests and computer simulations. The factors influencing indoor air movement are investigated for a single room. Cross-ventilation in two apartments is studied, and the air change efficiency in a Chinese kitchen is calculated with CFD techniques. The thermal performance of ventilated roofs, a simple and widely used type of roof in the region, is specially addressed by means of a full-scale measurement, wind tunnel tests and computer simulations. An integrated study of passive cooling approaches and factors affecting indoor thermal comfort is carried out through a case study in a southern Chinese city, Guangzhou. This thesis demonstrates that passive cooling measure have a high potential in significantly improving indoor thermal conditions during summer. This study also gives discussions and conclusions on the evaluation of indoor thermal environment; effects influencing cross-ventilation in apartments; design guidelines for ventilated roofs and an integrated study of passive cooling. 111 refs, 83 figs, 65 tabs

Effect of energy renovation on indoor air quality in multifamily residential buildings in Slovakia

DEFF Research Database (Denmark)

Földváry, Veronika; Bekö, Gabriel; Langer, Sarka

2017-01-01

efficiency of these buildings rarely consider their impact on the indoor air quality (IAQ). The objective of the present study was to evaluate the impact of simple energy renovation on IAQ, air exchange rates (AER) and occupant satisfaction in Slovak residential buildings. Three pairs of identical naturally...... of nitrogen dioxide (NO2), formaldehyde and total and individual volatile organic compounds (VOC) were also measured. CO2 concentrations were significantly higher and AERs were lower in the renovated buildings. Formaldehyde concentrations increased after renovation and were positively correlated with CO2...

Indoor air quality environmental information handbook: Building system characteristics

International Nuclear Information System (INIS)

1987-01-01

This manual, the third in a series, focuses on residential building system characteristics and their effects on indoor air quality. The manual addresses: residential indoor air pollutants by source, indoor concentrations, health effects, source control and mitigation techniques, standards and guidelines; building system characteristics of air exchange, pollutant source strength, residence volume, site characteristics, structural design, construction, and operation, infiltration and ventilation system, building occupancy; and monitoring methods

Indoor air quality in mechanically ventilated residential dwellings/low-rise buildings: A review of existing information

DEFF Research Database (Denmark)

Aganovic, Amar; Hamon, Mathieu; Kolarik, Jakub

Mechanical ventilation has become a mandatory requirement in multiple European standards addressing indoor air quality (IAQ) and ventilation in residential dwellings (single family houses and low-rise apartment buildings). This article presents the state of the art study through a review...... of the existing literature, to establish a link between ventilation rate and key indoor air pollutants. Design characteristics of a mechanical ventilation system such as supply/exhaustairflow, system and design of supply and exhaust outlets were considered. The performance of various ventilation solutionswas......-house ventilation rate was reported below 0.5h-1 or 14 l/s·person in bedrooms, the concentrations of the pollutants elevated above minimum threshold limits (CO2>1350 ppm; TVOC >3000 μg/m3) defined by the standard. Insufficient or non-existent supply of air was related to significantly higher pollutant...

Indoor air quality in green buildings: A case-study in a residential high-rise building in the northeastern United States.

Science.gov (United States)

Xiong, Youyou; Krogmann, Uta; Mainelis, Gediminas; Rodenburg, Lisa A; Andrews, Clinton J

2015-01-01

Improved indoor air quality (IAQ) is one of the critical components of green building design. Green building tax credit (e.g., New York State Green Building Tax Credit (GBTC)) and certification programs (e.g., Leadership in Energy & Environmental Design (LEED)) require indoor air quality measures and compliance with allowable maximum concentrations of common indoor air pollutants. It is not yet entirely clear whether compliance with these programs results in improved IAQ and ultimately human health. As a case in point, annual indoor air quality measurements were conducted in a residential green high-rise building for five consecutive years by an industrial hygiene contractor to comply with the building's GBTC requirements. The implementation of green design measures resulted in better IAQ compared to data in references of conventional homes for some parameters, but could not be confirmed for others. Relative humidity and carbon dioxide were satisfactory according to existing standards. Formaldehyde levels during four out of five years were below the most recent proposed exposure limits found in the literature. To some degree, particulate matter (PM) levels were lower than that in studies from conventional residential buildings. Concentrations of Volatile Organic Compounds (VOCs) with known permissible exposure limits were below levels known to cause chronic health effects, but their concentrations were inconclusive regarding cancer health effects due to relatively high detection limits. Although measured indoor air parameters met all IAQ maximum allowable concentrations in GBTC and applicable LEED requirements at the time of sampling, we argue that these measurements were not sufficient to assess IAQ comprehensively because more sensitive sampling/analytical methods for PM and VOCs are needed; in addition, there is a need for a formal process to ensure rigor and adequacy of sampling and analysis methods. Also, we suggest that a comprehensive IAQ assessment should

Predicting personal exposure to airborne carbonyls using residential measurements and time/activity data

Science.gov (United States)

Liu, Weili; Zhang, Junfeng (Jim); Korn, Leo R.; Zhang, Lin; Weisel, Clifford P.; Turpin, Barbara; Morandi, Maria; Stock, Tom; Colome, Steve

As a part of the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study, 48 h integrated residential indoor, outdoor, and personal exposure concentrations of 10 carbonyls were simultaneously measured in 234 homes selected from three US cities using the Passive Aldehydes and Ketones Samplers (PAKS). In this paper, we examine the feasibility of using residential indoor concentrations to predict personal exposures to carbonyls. Based on paired t-tests, the means of indoor concentrations were not different from those of personal exposure concentrations for eight out of the 10 measured carbonyls, indicating indoor carbonyls concentrations, in general, well predicted the central tendency of personal exposure concentrations. In a linear regression model, indoor concentrations explained 47%, 55%, and 65% of personal exposure variance for formaldehyde, acetaldehyde, and hexaldehyde, respectively. The predictability of indoor concentrations on cross-individual variability in personal exposure for the other carbonyls was poorer, explainingexposure concentrations. It was found that activities related to driving a vehicle and performing yard work had significant impacts on personal exposures to a few carbonyls.

Indoor temperature changes after retrofit: inferences based on electricity billing data for nonparticipants and participants in the BPA Residential Weatherization Program

Energy Technology Data Exchange (ETDEWEB)

Hirst, E.; White, D.

1985-07-01

This report discusses changes in indoor temperatures in response to retrofit improvements. The data on which this analysis is based are from an evaluation of the Bonneville Power Administration (BPA) interim Residential Weatherization Program. The BPA program, operated through participating private and public utilities throughout the Pacific Northwest, offered financial assistance (generally a cash rebate) to encourage installation of energy-efficiency improvements to existing homes in the region. These retrofits included attic, wall, floor and heating duct insulation; storm windows and doors; clock thermostats; and caulking and weatherstripping. This program, which operated during 1982 and 1983, weatherized 104 thousand homes at a total cost to BPA of $157 million. In mid-1983, staff at Oak Ridge National Laboratory and Evaluation Research Corporation began an evaluation of the BPA program. The primary focus of this evaluation was assessment of the actual electricity saving that can be attributed to the program (Hirst, et al., 1985). These savings estimates were used to help assess the economic attractiveness of the program to participants, the BPA power system, and the Pacific Northwest region as a whole.

Influence of ambient (outdoor) sources on residential indoor and personal PM2.5 concentrations: analyses of RIOPA data.

Science.gov (United States)

Meng, Qing Yu; Turpin, Barbara J; Korn, Leo; Weisel, Clifford P; Morandi, Maria; Colome, Steven; Zhang, Junfeng Jim; Stock, Thomas; Spektor, Dalia; Winer, Arthur; Zhang, Lin; Lee, Jong Hoon; Giovanetti, Robert; Cui, William; Kwon, Jaymin; Alimokhtari, Shahnaz; Shendell, Derek; Jones, Jennifer; Farrar, Corice; Maberti, Silvia

2005-01-01

The Relationship of Indoor, Outdoor and Personal Air (RIOPA) study was designed to investigate residential indoor, outdoor and personal exposures to several classes of air pollutants, including volatile organic compounds, carbonyls and fine particles (PM2.5). Samples were collected from summer, 1999 to spring, 2001 in Houston (TX), Los Angeles (CA) and Elizabeth (NJ). Indoor, outdoor and personal PM2.5 samples were collected at 212 nonsmoking residences, 162 of which were sampled twice. Some homes were chosen due to close proximity to ambient sources of one or more target analytes, while others were farther from sources. Median indoor, outdoor and personal PM2.5 mass concentrations for these three sites were 14.4, 15.5 and 31.4 microg/m3, respectively. The contributions of ambient (outdoor) and nonambient sources to indoor and personal concentrations were quantified using a single compartment box model with measured air exchange rate and a random component superposition (RCS) statistical model. The median contribution of ambient sources to indoor PM2.5 concentrations using the mass balance approach was estimated to be 56% for all study homes (63%, 52% and 33% for California, New Jersey and Texas study homes, respectively). Reasonable variations in model assumptions alter median ambient contributions by less than 20%. The mean of the distribution of ambient contributions across study homes agreed well for the mass balance and RCS models, but the distribution was somewhat broader when calculated using the mass balance model with measured air exchange rates.

Residential radon survey in Finland

International Nuclear Information System (INIS)

Arvela, H.; Maekelaeinen, I.; Castren, O.

1993-02-01

The study measured the indoor radon concentration in the dwellings of 3074 persons, selected randomly from the central population register of Finland. Alpha track detectors and two consecutive half year measuring periods were used. The national mean of indoor radon concentration for persons living in low-rise residential buildings as well as blocks of flats was 145 and 82 Bq/m 3 , respectively. The mean for the total population was 123 Bq/m 3 . Based on the decision of the Ministry of Social Affairs and Health in 1992, the indoor radon concentration should not exceed 400 Bq/m 3 in already existing houses, the target for new construction being less than 200 Bq/m 3 . According to the study, the percentage of the Finnish population living in houses with an indoor radon concentration exceeding 200, 400 and 800 Bq/m 3 was 12.3 %, 3.6 % and 1.0 %

Current Indoor Air Quality in Japan.

Science.gov (United States)

Jinno, Hideto

2016-01-01

People spend more than two thirds of their daily time indoors. Hence, maintaining a healthy indoor environment is indispensable for the prevention of building related illness. In Japan, guidelines for indoor air quality have been established for 13 volatile/semi-volatile organic compounds (VOCs/SVOCs). These guidelines are now under revision by the Committee on Sick House Syndrome: Indoor Air Pollution. In order to gain information on the current indoor air pollutants and their levels, we carried out a nation-wide survey of VOCs and aldehydes in indoor residential air during 2012-2013. In this review, I concisely summarized the current indoor air quality of Japan.

Using a Ventilation Controller to Optimize Residential Passive Ventilation For Energy and Indoor Air Quality

Energy Technology Data Exchange (ETDEWEB)

Turner, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2014-08-01

One way to reduce the energy impact of providing residential ventilation is to use passive and hybrid systems. However, these passive and hybrid (sometimes called mixed-mode) systems must still meet chronic and acute health standards for ventilation. This study uses a computer simulation approach to examine the energy and indoor air quality (IAQ) implications of passive and hybrid ventilation systems, in 16 California climate zones. Both uncontrolled and flow controlled passive stacks are assessed. A new hybrid ventilation system is outlined that uses an intelligent ventilation controller to minimise energy use, while ensuring chronic and acute IAQ standards are met. ASHRAE Standard 62.2-2010 – the United States standard for residential ventilation - is used as the chronic standard, and exposure limits for PM_2.5, formaldehyde and NO₂ are used as the acute standards.The results show that controlled passive ventilation and hybrid ventilation can be used in homes to provide equivalent IAQ to continuous mechanical ventilation, for less use of energy.

Indoor air quality environmental information handbook: Combustion sources

Energy Technology Data Exchange (ETDEWEB)

1990-06-01

This environmental information handbook was prepared to assist both the non-technical reader (i.e., homeowner) and technical persons (such as researchers, policy analysts, and builders/designers) in understanding the current state of knowledge regarding combustion sources of indoor air pollution. Quantitative and descriptive data addressing the emissions, indoor concentrations, factors influencing indoor concentrations, and health effects of combustion-generated pollutants are provided. In addition, a review of the models, controls, and standards applicable to indoor air pollution from combustion sources is presented. The emphasis is on the residential environment. The data presented here have been compiled from government and privately-funded research results, conference proceedings, technical journals, and recent publications. It is intended to provide the technical reader with a comprehensive overview and reference source on the major indoor air quality aspects relating to indoor combustion activities, including tobacco smoking. In addition, techniques for determining potential concentrations of pollutants in residential settings are presented. This is an update of a 1985 study documenting the state of knowledge of combustion-generated pollutants in the indoor environment. 191 refs., 51 figs., 71 tabs.

CFD simulation research on residential indoor air quality.

Science.gov (United States)

Yang, Li; Ye, Miao; He, Bao-Jie

2014-02-15

Nowadays people are excessively depending on air conditioning to create a comfortable indoor environment, but it could cause some health problems in a long run. In this paper, wind velocity field, temperature field and air age field in a bedroom with wall-hanging air conditioning running in summer are analyzed by CFD numerical simulation technology. The results show that wall-hanging air conditioning system can undertake indoor heat load and conduct good indoor thermal comfort. In terms of wind velocity, air speed in activity area where people sit and stand is moderate, most of which cannot feel wind flow and meet the summer indoor wind comfort requirement. However, for air quality, there are local areas without ventilation and toxic gases not discharged in time. Therefore it is necessary to take effective measures to improve air quality. Compared with the traditional measurement method, CFD software has many advantages in simulating indoor environment, so it is hopeful for humans to create a more comfortable, healthy living environment by CFD in the future. Copyright © 2013 Elsevier B.V. All rights reserved.

INFORMATION SYSTEM SALES OF INDOOR AND OUTDOOR ORNAMENTAL PLANTS-BASED ONLINE

Directory of Open Access Journals (Sweden)

Sutedi Sutedi

2017-05-01

Full Text Available Ornamental plants have fairly high commercial value and much sought after by various circles. The prospect is in the business of ornamental plants can be said very brilliant and profitable. Where is in the business of ornamental plants can bring about advantages not the least. The business struggled with ornamental plants can have very favorable prospects for the long term. There are an awful lot of various kinds of ornamental plants that we can choose to use as ornaments to beautify residential home. The ornamental plants can be used as indoor ornamental plants placed in homes or can also be used as outdoor ornamental plants grown in the garden. Ornamental plants while more popular community-wide information system for ornamental plant however is currently designed specifically and not many people who know the information on price and specs or type of indoor and outdoor ornamental plants so that the need for sales information system of indoor and outdoor ornamental plants-based online. With the sales information system of Indoor and Outdoor ornamental plants-based online is expected to facilitate the customers, business processes that occur in the company's units, unit – units that exist within the system a functioning production units as the unit working on/produce ornamental plants. With the utilization of the system marketing media, promoting, finding new customers, the sales process, recapitulation payment of ornamental plants, control the conditions of stock products, development and delivery of products to customers including convincing the product gets to the customer

Residential radon in Finland: sources, variation, modelling and dose comparisons

Energy Technology Data Exchange (ETDEWEB)

Arvela, H

1995-09-01

The study deals with sources of indoor radon in Finland, seasonal variations in radon concentration, the effect of house construction and ventilation and also with the radiation dose from indoor radon and terrestrial gamma radiation. The results are based on radon measurements in approximately 4000 dwellings and on air exchange measurements in 250 dwellings as well as on model calculations. The results confirm that convective soil air flow is by far the most important source of indoor radon in Finnish low-rise residential housing. (97 refs., 61 figs., 30 tabs.).

Residential radon in Finland: sources, variation, modelling and dose comparisons

International Nuclear Information System (INIS)

Arvela, H.

1995-09-01

The study deals with sources of indoor radon in Finland, seasonal variations in radon concentration, the effect of house construction and ventilation and also with the radiation dose from indoor radon and terrestrial gamma radiation. The results are based on radon measurements in approximately 4000 dwellings and on air exchange measurements in 250 dwellings as well as on model calculations. The results confirm that convective soil air flow is by far the most important source of indoor radon in Finnish low-rise residential housing. (97 refs., 61 figs., 30 tabs.)

Analysis Thermal Comfort Condition in Complex Residential Building, Case Study: Chiangmai, Thailand

Science.gov (United States)

Juangjandee, Warangkana

2017-10-01

Due to the increasing need for complex residential buildings, it appears that people migrate into the high-density urban areas because the infrastructural facilities can be easily found in the modern metropolitan areas. Such rapid growth of urbanization creates congested residential buildings obstructing solar radiation and wind flow, whereas most urban residents spend 80-90% of their time indoor. Furthermore, the buildings were mostly built with average materials and construction detail. This causes high humidity condition for tenants that could promote mould growth. This study aims to analyse thermal comfort condition in complex residential building, Thailand for finding the passive solution to improve indoor air quality and respond to local conditions. The research methodology will be in two folds: 1) surveying on case study 2) analysis for finding the passive solution of reducing humidity indoor air The result of the survey indicated that the building need to find passive solution for solving humidity problem, that can be divided into two ways which raising ventilation and indoor temperature including increasing wind-flow ventilation and adjusting thermal temperature, for example; improving building design and stack driven ventilation. For raising indoor temperature or increasing mean radiant temperature, daylight can be passive solution for complex residential design for reducing humidity and enhance illumination indoor space simultaneous.

Enabling Indoor Location-Based Services

DEFF Research Database (Denmark)

Radaelli, Laura

Indoor spaces have always attracted interest from different scientific disciplines. Relatively recent interest in indoor settings by computer scientists is driven in part by the increasing use of smartphones, which serve as a platform for service delivery and can generate extensive volumes...... of trajectory data that can be used to study how people actually use indoor spaces. In this dissertation, we contribute partial solutions that address challenges in indoor positioning and indoor trajectory management and analysis. The key enabler of indoor location-based services and indoor movement analysis...... is a well-functioning positioning system that can be easily deployed in most public places. Different technologies are able to provide indoor positioning with different accuracy and coverage, but it is difficult to find a technology that by itself can provide good positioning in the many different layouts...

Graph Model Based Indoor Tracking

DEFF Research Database (Denmark)

Jensen, Christian Søndergaard; Lu, Hua; Yang, Bin

2009-01-01

The tracking of the locations of moving objects in large indoor spaces is important, as it enables a range of applications related to, e.g., security and indoor navigation and guidance. This paper presents a graph model based approach to indoor tracking that offers a uniform data management...

A Semantic-Based Indexing for Indoor Moving Objects

OpenAIRE

Tingting Ben; Xiaolin Qin; Ning Wang

2014-01-01

The increasing availability of indoor positioning, driven by techniques like RFID, Bluetooth, and smart phones, enables a variety of indoor location-based services (LBSs). Efficient queries based on semantic-constraint in indoor spaces play an important role in supporting and boosting LBSs. However, the existing indoor index techniques cannot support these semantic constraints-based queries. To solve this problem, this paper addresses the challenge of indexing moving objects in indoor spaces,...

Indoor air pollution: Sources and control. July 1988-January 1990 (Citations from the NTIS data base). Report for July 1988-January 1990

International Nuclear Information System (INIS)

1990-01-01

This bibliography contains citations concerning indoor air pollution in residential, commercial, industrial, and institutional buildings. Indoor air quality assessment, health hazard evaluation, and contaminant identification and measurement are discussed. Indoor air pollution control methods and equipment are evaluated. Air quality analyses of energy efficient buildings are presented. Indoor air pollution from radon and asbestos are discussed in other bibliographies. (This updated bibliography contains 75 citations, 16 of which are new entries to the previous edition.)

ASHRAE and residential ventilation

Energy Technology Data Exchange (ETDEWEB)

Sherman, Max H.

2003-10-01

In the last quarter of a century, the western world has become increasingly aware of environmental threats to health and safety. During this period, people psychologically retreated away from outdoors hazards such as pesticides, smog, lead, oil spills, and dioxin to the seeming security of their homes. However, the indoor environment may not be healthier than the outdoor environment, as has become more apparent over the past few years with issues such as mold, formaldehyde, and sick-building syndrome. While the built human environment has changed substantially over the past 10,000 years, human biology has not; poor indoor air quality creates health risks and can be uncomfortable. The human race has found, over time, that it is essential to manage the indoor environments of their homes. ASHRAE has long been in the business of ventilation, but most of the focus of that effort has been in the area of commercial and institutional buildings. Residential ventilation was traditionally not a major concern because it was felt that, between operable windows and envelope leakage, people were getting enough outside air in their homes. In the quarter of a century since the first oil shock, houses have gotten much more energy efficient. At the same time, the kinds of materials and functions in houses changed in character in response to people's needs. People became more environmentally conscious and aware not only about the resources they were consuming but about the environment in which they lived. All of these factors contributed to an increasing level of public concern about residential indoor air quality and ventilation. Where once there was an easy feeling about the residential indoor environment, there is now a desire to define levels of acceptability and performance. Many institutions--both public and private--have interests in Indoor Air Quality (IAQ), but ASHRAE, as the professional society that has had ventilation as part of its mission for over 100 years, is the

Internet-Based Indoor Navigation Services

OpenAIRE

Zeinalipour-Yazti, Demetrios; Laoudias, Christos; Georgiou, Kyriakos

2017-01-01

Smartphone advances are leading to a class of Internet-based Indoor Navigation services. IIN services rely on geolocation databases that store indoor models, comprising floor maps and points of interest, along with wireless, light, and magnetic signals for localizing users. Developing IIN services creates new information management challenges - such as crowdsourcing indoor models, acquiring and fusing big data velocity signals, localization algorithms, and custodians' location privacy. Here, ...

Study on indoor radon exposure and its effect on human health

International Nuclear Information System (INIS)

Lu Xinwei

2005-01-01

Radon and its daughters relate to people health. Radon widely exists in the nature. The paper discusses the source, exposure and activity level of indoor radon, systematically analyzes the hazards and dose-response of residential radon exposure, and at last indicates the concrete method of controlling residential radon concentration. By interdicting radon pollution source and ventilation might effectively reduce indoor radon concentration and improve environmental air quality. (authors)

Window opening behaviour: simulations of occupant behaviour in residential buildings using models based on a field survey

DEFF Research Database (Denmark)

Valentina, Fabi; Andersen, Rune Korsholm; Corgnati, Stefano Paolo

2012-01-01

Window opening behaviour has been shown to have a significant impact on airflow rates and hence energy consumption. Nevertheless, the inhabitant behaviour related to window opening in residential buildings is currently poorly investigated through both field surveys and building energy simulations....... In particular, reliable information regarding user behaviour in residential buildings is crucial for suitable prediction of building performance (energy consumption, indoor environmental quality, etc.). To face this issue, measurements of indoor climate and outdoor environmental parameters and window “opening...... and closing” actions were performed in 15 dwellings from January to August 2008 in Denmark. Probabilistic models of inhabitants’ window “opening and closing” behaviour were developed and implemented in the energy simulation software IDA ICE to improve window opening and closing strategies in simulations...

Residential Indoor Temperature Study

Energy Technology Data Exchange (ETDEWEB)

Booten, Chuck [National Renewable Energy Lab. (NREL), Golden, CO (United States); Robertson, Joseph [National Renewable Energy Lab. (NREL), Golden, CO (United States); Christensen, Dane [National Renewable Energy Lab. (NREL), Golden, CO (United States); Heaney, Mike [Arrow Electronics, Centennial, CO (United States); Brown, David [Univ. of Virginia, Charlottesville, VA (United States); Norton, Paul [Norton Energy Research and Development, Boulder, CO (United States); Smith, Chris [Ingersoll-Rand Corp., Dublin (Ireland)

2017-04-07

In this study, we are adding to the body of knowledge around answering the question: What are good assumptions for HVAC set points in U.S. homes? We collected and analyzed indoor temperature data from US homes using funding from the U.S. Department of Energy's Building America (BA) program, due to the program's reliance on accurate energy simulation of homes. Simulations are used to set Building America goals, predict the impact of new building techniques and technologies, inform research objectives, evaluate home performance, optimize efficiency packages to meet savings goals, customize savings approaches to specific climate zones, and myriad other uses.

Comparison of Single-Point and Continuous Sampling Methods for Estimating Residential Indoor Temperature and Humidity.

Science.gov (United States)

Johnston, James D; Magnusson, Brianna M; Eggett, Dennis; Collingwood, Scott C; Bernhardt, Scott A

2015-01-01

Residential temperature and humidity are associated with multiple health effects. Studies commonly use single-point measures to estimate indoor temperature and humidity exposures, but there is little evidence to support this sampling strategy. This study evaluated the relationship between single-point and continuous monitoring of air temperature, apparent temperature, relative humidity, and absolute humidity over four exposure intervals (5-min, 30-min, 24-hr, and 12-days) in 9 northern Utah homes, from March-June 2012. Three homes were sampled twice, for a total of 12 observation periods. Continuous data-logged sampling was conducted in homes for 2-3 wks, and simultaneous single-point measures (n = 114) were collected using handheld thermo-hygrometers. Time-centered single-point measures were moderately correlated with short-term (30-min) data logger mean air temperature (r = 0.76, β = 0.74), apparent temperature (r = 0.79, β = 0.79), relative humidity (r = 0.70, β = 0.63), and absolute humidity (r = 0.80, β = 0.80). Data logger 12-day means were also moderately correlated with single-point air temperature (r = 0.64, β = 0.43) and apparent temperature (r = 0.64, β = 0.44), but were weakly correlated with single-point relative humidity (r = 0.53, β = 0.35) and absolute humidity (r = 0.52, β = 0.39). Of the single-point RH measures, 59 (51.8%) deviated more than ±5%, 21 (18.4%) deviated more than ±10%, and 6 (5.3%) deviated more than ±15% from data logger 12-day means. Where continuous indoor monitoring is not feasible, single-point sampling strategies should include multiple measures collected at prescribed time points based on local conditions.

Indoor air-quality measurements in energy-efficient residential buildings

Energy Technology Data Exchange (ETDEWEB)

Berk, J.V.; Hollowell, C.D.; Pepper, J.H.; Young, R.

1980-05-01

The potential impact on indoor air quality of energy-conserving measures that reduce ventilation is being assessed in a field-monitoring program conducted by the Lawrence Berkeley Laboratory. Using a mobile laboratory, on-site monitoring of infiltration rate, carbon dioxide, carbon monoxide, nitrogen dioxide, nitric oxide, ozone, sulfur dioxide, formaldehyde, total aldehydes, and particulates was conducted in three houses designed to be energy-efficient. Preliminary results show that energy-conserving design features that reduce air-exchange rates compromise indoor air quality; specifically, indoor levels of several pollutants were found to exceed levels detected outdoors. Although the indoor levels of most pollutants are within limits established by present outdoor air-quality standards, considerable work remains to be accomplished before health-risk effects can be accurately assessed and broad-scale regulatory guidelines revised to comply with energy-conservation goals.

Volatile organic compound conversion by ozone, hydroxyl radicals, and nitrate radicals in residential indoor air: Magnitudes and impacts of oxidant sources

Science.gov (United States)

Waring, Michael S.; Wells, J. Raymond

2015-04-01

Indoor chemistry may be initiated by reactions of ozone (O3), the hydroxyl radical (OH), or the nitrate radical (NO3) with volatile organic compounds (VOC). The principal indoor source of O3 is air exchange, while OH and NO3 formation are considered as primarily from O3 reactions with alkenes and nitrogen dioxide (NO2), respectively. Herein, we used time-averaged models for residences to predict O3, OH, and NO3 concentrations and their impacts on conversion of typical residential VOC profiles, within a Monte Carlo framework that varied inputs probabilistically. We accounted for established oxidant sources, as well as explored the importance of two newly realized indoor sources: (i) the photolysis of nitrous acid (HONO) indoors to generate OH and (ii) the reaction of stabilized Criegee intermediates (SCI) with NO2 to generate NO3. We found total VOC conversion to be dominated by reactions both with O3, which almost solely reacted with D-limonene, and also with OH, which reacted with D-limonene, other terpenes, alcohols, aldehydes, and aromatics. VOC oxidation rates increased with air exchange, outdoor O3, NO2 and D-limonene sources, and indoor photolysis rates; and they decreased with O3 deposition and nitric oxide (NO) sources. Photolysis was a strong OH formation mechanism for high NO, NO2, and HONO settings, but SCI/NO2 reactions weakly generated NO3 except for only a few cases.

Maximizing Information from Residential Measurements of Volatile Organic Compounds

Energy Technology Data Exchange (ETDEWEB)

Maddalena, Randy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Li, Na [Berkeley Analytical Associates, Richmond, CA (United States); Hodgson, Alfred [Berkeley Analytical Associates, Richmond, CA (United States); Offermann, Francis [Indoor Environmental Engineering, San Francisco, CA (United States); Singer, Brett [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2013-02-01

Continually changing materials used in home construction and finishing can introduce new chemicals or changes in the VOC profile in residential air and the trend towards tighter homes can lead to higher exposure concentrations for many indoor sources. However, the complex mixture of VOCs in residential air makes it difficult to discover emerging contaminants and/or trends in pollutant profiles. The purpose of this study is to prepare a comprehensive library of chemicals found in homes, along with a semi-quantitative approach to maximize the information gained from VOC measurements. We carefully reviewed data from 108 new California homes and identified 238 individual compounds. The majority of the identified VOCs originated indoors. Only 31% were found to have relevant health based exposure guidelines and less than 10% had a chronic reference exposure level (CREL). The finding highlights the importance of extending IAQ studies to include a wider range of VOCs

Energy and IAQ Implications of Residential Ventilation Cooling

Energy Technology Data Exchange (ETDEWEB)

Turner, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2014-08-01

This study evaluates the energy, humidity and indoor air quality (IAQ) implications of residential ventilation cooling in all U.S. IECC climate zones. A computer modeling approach was adopted, using an advanced residential building simulation tool with airflow, energy and humidity models. An economizer (large supply fan) was simulated to provide ventilation cooling while outdoor air temperatures were lower than indoor air temperatures (typically at night). The simulations were performed for a full year using one-minute time steps to allow for scheduling of ventilation systems and to account for interactions between ventilation and heating/cooling systems.

Modeling indoor air pollution of outdoor origin in homes of SAPALDIA subjects in Switzerland.

Science.gov (United States)

Meier, Reto; Schindler, Christian; Eeftens, Marloes; Aguilera, Inmaculada; Ducret-Stich, Regina E; Ineichen, Alex; Davey, Mark; Phuleria, Harish C; Probst-Hensch, Nicole; Tsai, Ming-Yi; Künzli, Nino

2015-09-01

Given the shrinking spatial contrasts in outdoor air pollution in Switzerland and the trends toward tightly insulated buildings, the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults (SAPALDIA) needs to understand to what extent outdoor air pollution remains a determinant for residential indoor exposure. The objectives of this paper are to identify determining factors for indoor air pollution concentrations of particulate matter (PM), ultrafine particles in the size range from 15 to 300nm, black smoke measured as light absorbance of PM (PMabsorbance) and nitrogen dioxide (NO2) and to develop predictive indoor models for SAPALDIA. Multivariable regression models were developed based on indoor and outdoor measurements among homes of selected SAPALDIA participants in three urban (Basel, Geneva, Lugano) and one rural region (Wald ZH) in Switzerland, various home characteristics and reported indoor sources such as cooking. Outdoor levels of air pollutants were important predictors for indoor air pollutants, except for the coarse particle fraction. The fractions of outdoor concentrations infiltrating indoors were between 30% and 66%, the highest one was observed for PMabsorbance. A modifying effect of open windows was found for NO2 and the ultrafine particle number concentration. Cooking was associated with increased particle and NO2 levels. This study shows that outdoor air pollution remains an important determinant of residential indoor air pollution in Switzerland. Copyright © 2015 Elsevier Ltd. All rights reserved.

Influence of ventilation strategies on indoor radon concentrations based on a semiempirical model for Florida-style houses

International Nuclear Information System (INIS)

Hintenlang, D.E.; Al-Ahmady, K.K.

1994-01-01

Measurements in a full-scale experimental facility are used to benchmark a semiempirical model for predicting indoor radon concentrations for Florida-style houses built using slab-on-grade construction. The model is developed to provide time-averaged indoor radon concentrations from quantitative relationships between the time-dependent radon entry and elimination mechanisms that have been demonstrated to be important for this style of residential construction. The model successfully predicts indoor radon concentrations in the research structure for several pressure and ventilation conditions. Parametric studies using the model illustrate how different ventilation strategies affect indoor radon concentrations. It is demonstrated that increasing house ventilation rates by increasing the effective leakage area of the house shell does not reduce indoor radon concentrations as effectively as increasing house ventilation rates by controlled duct ventilation associated with the heating, ventilating, and air conditioning system. The latter strategy provides the potential to minimize indoor radon concentrations while providing positive control over the quality of infiltration air. 9 refs., 5 figs

Indoor radon concentration and outdoor/indoor pressure difference correlation

International Nuclear Information System (INIS)

Cechak, T.; Fronka, A.; Moucka, L.

2004-01-01

In the current approach to the radon issue, the radon risk for people living in a building is estimated based on the average indoor radon concentration. Short-term measurements as usually applied fail to reflect the wide range of radon variations arising from ventilation, radon supply and, in particular, human activities in the building. For this reason, efforts are made to find a new approach to the assessment of the quality of a building as a radon barrier, independent of the weather conditions and residential habits. A simple model of radon volume activity entering the building at a constant rate and simultaneously ventilated at a constant rate is applicable to this task. The rate of radon ingress can be regarded as a parameter making it possible to quantify the leakage of structures provided the barrier against the radon in a soil gas. The ventilation rate, on the other hand, characterizes the leakage of the whole building envelope at a given outdoor/indoor pressure difference. A unique measuring technique called the blower door exists whereby a defined pressure difference between the indoor and outdoor atmosphere can be established. Under such conditions both the ventilation rate and the rate of radon ingress can be measured and expressed as a function of the pressure difference. An analysis of the model of a room with a constant ventilation and constant radon supply is presented and the relationship between radon supply and ventilation rate can be assumed. Some experimental results show how the model can be utilized. The real indoor-outdoor air pressure differences, the indoor-soil air pressure differences, and some effects of different ventilation regimes are given. Other experiments, which have been done by using the blower door method, illustrate the possible effects and some restrictions for a routine application are discussed

Health impacts due to personal exposure to fine particles caused by insulation of residential buildings in Europe

Science.gov (United States)

Gens, Alexandra; Hurley, J. Fintan; Tuomisto, Jouni T.; Friedrich, Rainer

2014-02-01

The insulation of residential buildings affects human exposure to fine particles. According to current EU guidelines, insulation is regulated for energy saving reasons. As buildings become tighter, the air exchange rate is reduced and, thus, the indoor concentration of pollutants is increased if there are significant indoor sources. While usually the effects of heat insulation and increase of the air-tightness of buildings on greenhouse gas emissions are highlighted, the negative impacts on human health due to higher indoor concentrations are not addressed. Thus, we investigated these impacts using scenarios in three European countries, i. e. Czech Republic, Switzerland and Greece. The assessment was based on modelling the human exposure to fine particles originating from sources of particles within outdoor and indoor air, including environmental tobacco smoke. Exposure response relationships were derived to link (adverse) health effects to the exposure. Furthermore, probable values for the parameters influencing the infiltration of fine particles into residential buildings were modelled. Results show that the insulation and increase of the air-tightness of residential buildings leads to an overall increase of the mean population exposure - and consequently adverse health effects - in all considered countries (ranging for health effects from 0.4% in Czech Republic to 11.8% in Greece for 100% insulated buildings) due to an accumulation of particles indoors, especially from environmental tobacco smoke. Considering only the emission reductions in outdoor air (omitting changes in infiltration parameters) leads to a decrease of adverse health effects. This study highlights the importance of ensuring a sufficient air exchange rate when insulating buildings, e. g. by prescribing heat ventilation and air conditioning systems in new buildings and information campaigns on good airing practice in renovated buildings. It also shows that assessing policy measures based on the

Thermal Performance of Typical Residential Building in Karachi with Different Materials for Construction

Directory of Open Access Journals (Sweden)

Nafeesa Shaheen

2016-04-01

Full Text Available This research work deals with a study of a residential building located in climatic context of Karachi with the objective of being the study of thermal performance based upon passive design techniques. The study helps in reducing the electricity consumption by improving indoor temperatures. The existing residential buildings in Karachi were studied with reference to their planning and design, analyzed and evaluated. Different construction?s compositions of buildings were identified, surveyed and analyzed in making of the effective building envelops. Autodesk® Ecotect, 2011 was used to determine indoor comfort conditions and HVAC (Heating, Ventilation, Air-Conditioning and Cooling loads. The result of the research depicted significant energy savings of 38.5% in HVAC loads with proposed building envelop of locally available materials and glazing.

Measurements of MIMO Indoor Channels at 1800 MHz with Multiple Indoor and Outdoor Base Stations

Directory of Open Access Journals (Sweden)

Jaldén Niklas

2007-01-01

Full Text Available This paper proposes several configurations for multiple base stations in indoor MIMO systems and compares their performance. The results are based on channel measurements realized with a MIMO testbed. The receiver was moved along several routes and floors on an office building. Both outdoor and indoor locations are considered for the transmitters or base stations, which allow the analysis of not only indoor but also outdoor-to-indoor environment. The use of 2 base stations with different system level combinations of the two is analyzed. We show that the configuration with base station selection provides almost as good performance as a full water-filling scheme when the 2 base stations are placed at different locations. Also the spatial correlation properties for the different configurations are analyzed and the importance of considering path loss when evaluating capacity is highlighted.

Reducing burden of disease from residential indoor air exposures in Europe (HEALTHVENT project)

DEFF Research Database (Denmark)

Asikainen, Arja; Carrer, Paolo; Kephalopoulos, Stylianos

2016-01-01

), approximately 90 % of EU citizens live in areas where the World Health Organization (WHO) guidelines for air quality of particulate matter sized PM2.5) are not met. Since sources of pollution reside in both indoor and outdoor air, selecting the most appropriate ventilation strategy is not a simple...... matter (PM2.5), outdoor bioaerosols, volatile organic compounds (VOC), carbon oxide (CO) radon and dampness was estimated. The analysis was based on scenario comparison, using an outdoor-indoor mass-balance model and varying the ventilation rates. Health effects were estimated with burden of diseases (Bo...... air; and (iii) indoor source control, showed that all three approaches are able to provide substantial reductions in the health risks, varying from approximately 20 % to 44 %, corresponding to 400 000 and 900 000 saved healthy life years in EU-26. PM2.5 caused majority of the health effects in all...

Iron and zinc partitioning between coexisting stannite and sphalerite: a possible indicator of temperature and sulfur fugacity

Science.gov (United States)

Shimizu, M.; Shikazono, N.

1985-10-01

Stannite and sphalerite coexisting with iron sulfides (pyrite and/or pyrrhotite) from Japanese ore deposits associated with tin mineralization were analyzed. Based on the iron and zinc partitioning between stannite and sphalerite, the formation temperature and sulfur fugacity for this mineral assemblage were estimated. A good correlation between stannite-sphalerite temperatures and filling temperatures of fluid inclusions and sulfur isotope temperatures was obtained. This good correlation suggests that the stannite-sphalerite pair is a useful indicator of temperature and sulfur fugacity. It is deduced that the formation temperatures are not different for skarn-type, polymetallic vein-type and Sn-W vein-type deposits, whereas the sulfur fugacities are different; sulfur fugacities increase from the skarn-type through the Sn-W vein-type to the polymetallic vein-type deposits.

Response of consumer and research grade indoor air quality monitors to residential sources of fine particles.

Science.gov (United States)

Singer, B C; Delp, W W

2018-04-23

The ability to inexpensively monitor PM 2.5 to identify sources and enable controls would advance residential indoor air quality (IAQ) management. Consumer IAQ monitors incorporating low-cost optical particle sensors and connections with smart home platforms could provide this service if they reliably detect PM 2.5 in homes. In this study, particles from typical residential sources were generated in a 120 m 3 laboratory and time-concentration profiles were measured with 7 consumer monitors (2-3 units each), 2 research monitors (Thermo pDR-1500, MetOne BT-645), a Grimm Mini Wide-Range Aerosol Spectrometer (GRM), and a Tapered Element Oscillating Microbalance with Filter Dynamic Measurement System (FDMS), a Federal Equivalent Method for PM 2.5 . Sources included recreational combustion (candles, cigarettes, incense), cooking activities, an unfiltered ultrasonic humidifier, and dust. FDMS measurements, filter samples, and known densities were used to adjust the GRM to obtain time-resolved mass concentrations. Data from the research monitors and 4 of the consumer monitors-AirBeam, AirVisual, Foobot, Purple Air-were time correlated and within a factor of 2 of the estimated mass concentrations for most sources. All 7 of the consumer and both research monitors substantially under-reported or missed events for which the emitted mass was comprised of particles smaller than 0.3 μm diameter. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Procedures for Calculating Residential Dehumidification Loads

Energy Technology Data Exchange (ETDEWEB)

Winkler, Jon [National Renewable Energy Lab. (NREL), Golden, CO (United States); Booten, Chuck [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-06-01

Residential building codes and voluntary labeling programs are continually increasing the energy efficiency requirements of residential buildings. Improving a building's thermal enclosure and installing energy-efficient appliances and lighting can result in significant reductions in sensible cooling loads leading to smaller air conditioners and shorter cooling seasons. However due to fresh air ventilation requirements and internal gains, latent cooling loads are not reduced by the same proportion. Thus, it's becoming more challenging for conventional cooling equipment to control indoor humidity at part-load cooling conditions and using conventional cooling equipment in a non-conventional building poses the potential risk of high indoor humidity. The objective of this project was to investigate the impact the chosen design condition has on the calculated part-load cooling moisture load, and compare calculated moisture loads and the required dehumidification capacity to whole-building simulations. Procedures for sizing whole-house supplemental dehumidification equipment have yet to be formalized; however minor modifications to current Air-Conditioner Contractors of America (ACCA) Manual J load calculation procedures are appropriate for calculating residential part-load cooling moisture loads. Though ASHRAE 1% DP design conditions are commonly used to determine the dehumidification requirements for commercial buildings, an appropriate DP design condition for residential buildings has not been investigated. Two methods for sizing supplemental dehumidification equipment were developed and tested. The first method closely followed Manual J cooling load calculations; whereas the second method made more conservative assumptions impacting both sensible and latent loads.

Criteria For Specifikation Of The Indoor Environment Of Active House

DEFF Research Database (Denmark)

Foldbjerg, Peter; Hansen, Ellen Kathrine; Duer, Karsten

2011-01-01

The Active House Alliance has been formed by companies and organisations in the building design, components and construction industry to with the intention to improve the quality of the built environment through a balanced focus on indoor environment, energy and environment – and where the aspects...... of human health and wellbeing will be specifically considered. This paper presents the first version of the Active House specification for indoor environment for residential buildings (where specifications for energy and environment also exist). It is based on the EN 15251 philosophy, and with specific...... requirements to daylight, thermal environment, IAQ and acoustics. Requirements have been tightened compared to EN 15251, and will necessitate performance simulations....

Radon and aldehyde concentrations in the indoor environment. Final report

International Nuclear Information System (INIS)

Moschandreas, D.J.; Rector, H.E.

1981-04-01

Findings regarding indoor air contaminants in the energy-efficient residence (EER) in Mt. Airy, Maryland are reported. The objectives of the study were to collect and analyze relevant air quality samples (specifically radon and aldehydes), characterize the indoor air quality with respect to radon and aldehydes, and develop relationships between air infiltration rates and contaminant levels. One-fifth of the measured formaldehyde concentrations were in the range that may cause health concerns. Although indoor temperature and relative humidity affect indoor HCHO concentration, the elevated formaldehyde concentrations were measured under very low air infiltration rates. The data show that ventilation of the indoor air space is somewhat effective in reducing high HCHO concentrations. The operation of the heat exchanger led to an increase of the air infiltration rate which in turn resulted in substantial reduction of formaldehyde concentrations. A considerable number of the collected samples of indoor air displayed radon concentrations at levels higher than 1.0 to 4.0 nCim -3 (assuming an equilibrium factor of 0.5, these radon levels would correspond to working levels above the health guidelines suggested by the US EPA for homes in Florida built on land reclaimed from phosphate mining). As in the case of indoor formaldehyde concentrations, elevated indoor concentrations are substantially reduced when the infiltration rate is increased. The data base shows that the use of the air to air heat exchanger leads to reduction of indoor radon concentration by increasing the residential ventilation rate

Pilot study on indoor air quality: Managing indoor air-quality risks. Report on a meeting held in St. Michaels, Maryland on October 25-27, 1989

International Nuclear Information System (INIS)

1990-06-01

Included in this study are the following: quantifying future trends of indoor air quality as a basis for government policy plans; assessing indoor air quality risks of pesticides; formaldehyde emission standards in the Federal Republic of Germany; orientations and actions of the European Community in the assessment and prevention of indoor air pollution; EPA and indoor air quality; the non-regulatory approach to reducing risks from radon exposure; U.S. consumer product safety commission; a builders guide to healthy homes; WHO air quality guidelines for Europe; the approach to control indoor air quality in Italy; guidelines - ventilation classes; energy consequences of upgrading indoor air quality; Canada's guidelines for residential indoor air quality: rationale and scope; Canadian ventilation and venting standards; indoor air quality building surveys case studies; design of indoor air quality studies; summary findings of inter-ministerial committee on indoor air quality (Ontario); the Quebec approach; employee survey EPA headquarters; pollution in closed spaces and its consequences in conservation of works of art; and how Norwegian health authorities will handle indoor air quality problems

A neuro-fuzzy model for prediction of the indoor temperature in typical Australian residential buildings

Energy Technology Data Exchange (ETDEWEB)

Alasha' ary, Haitham; Moghtaderi, Behdad; Page, Adrian; Sugo, Heber [Priority Research Centre for Energy, Chemical Engineering, School of Engineering, Faculty of Engineering and Built Environment, the University of Newcastle, Callaghan, Newcastle, NSW 2308 (Australia)

2009-07-15

The Masonry Research Group at The University of Newcastle, Australia has embarked on an extensive research program to study the thermal performance of common walling systems in Australian residential buildings by studying the thermal behaviour of four representative purpose-built thermal test buildings (referred to as 'test modules' or simply 'modules' hereafter). The modules are situated on the university campus and are constructed from brick veneer (BV), cavity brick (CB) and lightweight (LW) constructions. The program of study has both experimental and analytical strands, including the use of a neuro-fuzzy approach to predict the thermal behaviour. The latter approach employs an experimental adaptive neuro-fuzzy inference system (ANFIS) which is used in this study to predict the room (indoor) temperatures of the modules under a range of climatic conditions pertinent to Newcastle (NSW, Australia). The study shows that this neuro-fuzzy model is capable of accurately predicting the room temperature of such buildings; thus providing a potential computationally efficient and inexpensive predictive tool for the more effective thermal design of housing. (author)

Oxygen fugacity control in piston-cylinder experiments: a re-evaluation

Science.gov (United States)

Jakobsson, Sigurdur; Blundy, Jon; Moore, Gordon

2014-06-01

Jakobsson (Contrib Miner Petrol 164(3):397-407, 2012) investigated a double capsule assembly for use in piston-cylinder experiments that would allow hydrous, high-temperature, and high-pressure experiments to be conducted under controlled oxygen fugacity conditions. Using a platinum outer capsule containing a metal oxide oxygen buffer (Ni-NiO or Co-CoO) and H2O, with an inner gold-palladium capsule containing hydrous melt, this study was able to compare the oxygen fugacity imposed by the outer capsule oxygen buffer with an oxygen fugacity estimated by the AuPdFe ternary system calibrated by Barr and Grove (Contrib Miner Petrol 160(5):631-643, 2010). H2O loss or gain, as well as iron loss to the capsule walls and carbon contamination, is often observed in piston-cylinder experiments and often go unexplained. Only a few have attempted to actually quantify various aspects of these changes (Brooker et al. in Am Miner 83(9-10):985-994, 1998; Truckenbrodt and Johannes in Am Miner 84:1333-1335, 1999). It was one of the goals of Jakobsson (Contrib Miner Petrol 164(3):397-407, 2012) to address these issues by using and testing the AuPdFe solution model of Barr and Grove (Contrib Miner Petrol 160(5):631-643, 2010), as well as to constrain the oxygen fugacity of the inner capsule. The oxygen fugacities of the analyzed melts were assumed to be equal to those of the solid Ni-NiO and Co-CoO buffers, which is incorrect since the melts are all undersaturated in H2O and the oxygen fugacities should therefore be lower than that of the buffer by 2 log.

Laser-Based and Ultra-Portable Gas Sensor for Indoor and Outdoor Formaldehyde (HCHO) Monitoring

Science.gov (United States)

Shutter, J. D.; Allen, N.; Paul, J.; Thiebaud, J.; So, S.; Scherer, J. J.; Keutsch, F. N.

2017-12-01

While used as a key tracer of oxidative chemistry in the atmosphere, formaldehyde (HCHO) is also a known human carcinogen and is listed and regulated by the United States EPA as a hazardous air pollutant. Combustion processes and photochemical oxidation of volatile organic compounds (VOCs) are the major outdoor sources of HCHO, and building materials and household products are ubiquitous sources of indoor HCHO. Due to the ease with which humans can be exposed to HCHO, it is imperative to monitor levels of both indoor and outdoor HCHO exposure in both short and long-term studies.High-quality direct and indirect methods of quantifying HCHO mixing ratios exist, but instrument size and user-friendliness can make them cumbersome or impractical for certain types of indoor and long-term outdoor measurements. In this study, we present urban HCHO measurements by using a new, commercially-available, ppbv-level accurate HCHO gas sensor (Aeris Technologies' MIRA Pico VOC Laser-Based Gas Analyzer) that is highly portable (29 cm x 20 cm x 10 cm), lightweight (3 kg), easy-to-use, and has low power (15 W) consumption. Using an ultra-compact multipass cell, an absorption path length of 13 m is achieved, resulting in a sensor capable of achieving ppbv/s sensitivity levels with no significant spectral interferences.To demonstrate the utility of the gas sensor for emissions measurements, a GPS was attached to the sensor's housing in order to map mobile HCHO measurements in real-time around the Boston, Massachusetts, metro area. Furthermore, the sensor was placed in residential and industrial environments to show its usefulness for indoor and outdoor pollution measurements. Lastly, we show the feasibility of using the HCHO sensor (or a network of them) in long-term monitoring stations for hazardous air pollutants.

Design an Indoor Air Quality Controller Based on LPC2478

Directory of Open Access Journals (Sweden)

Shi Shuheng

2014-07-01

Full Text Available Indoor air quality is very important to our lives, because we spend most of our time indoor. In order to improve the air quality of indoor, this paper designs an indoor environment quality monitoring and controlling system based on ARM microcontroller LPC2478. It will do a real-time monitoring work for detecting the indoor environmental factors and comprehensively evaluate its air quality level. While the indoor air quality status is "poor", this intelligent system will automatically start the heat exchange ventilator for indoor environmental quality improvement. The results compared to traditional natural ventilation method show the better performance of proposed system.

Indoor air quality in the Greater Beirut area: a characterization and modeling assessment

International Nuclear Information System (INIS)

El-Fadel, Mutasem; El-Hougeiri, Nisrine; Oulabi, Mawiya

2003-01-01

This report presents the assessment of IAQ at various environments selected from different geographic categories from the Greater Beirut area (GBA) in Lebanon. For this purpose, background information about indoor air quality was reviewed, existing conditions were characterized, an air-sampling program was implemented and mathematical modeling was conducted. Twenty-eight indoor buildings were selected from various geographic categories representing different environments (commercial and residential...). Indoor and outdoor air samples were collected and analyzed using carbon monoxide (CO), particulate matter (TSP), nitrogen dioxide (NO 2 ) and total volatile organic compounds (TVOC) as indicators of indoor air pollution (IAP).Samples were further analyzed using the energy dispersive x-ray fluorescence technique (EDXRF) for the presence of major priority metals including iron (Fe), calcium (Ca), zinc (Zn), lead (Pb), manganese (Mn), copper (Cu) and bromine (Br). Indoor and outdoor measured levels were compared to the American Society of Heating Refrigerating and Air-Conditioning Engineers (ASHRAE) and health-based National Ambient Air Quality standards (NAAQS), respectively. For the priority metals, on the other hand, indoor measured values were compared to occupational standards recommended by the National Institute of Occupational Safety and Health (NIOSH) and Occupational Safety and Health Administration (OSHA)

Light fidelity (LI-FI) based indoor communication system

OpenAIRE

Aftab, Farooq; khan, Muhammad Nafees Ulfat; Ali, Shahzad

2016-01-01

Indoor wireless communication is an essential part of next generation wireless communication system.For an indoor communication number of users and their device are increasing very rapidly so as a result capacity of frequency spectrum to accommodate further users in future is limited and also it would be difficult for service providers to provide more user reliable and high speed communication so this short come can be solve in future by using Li-Fi based indoor communication syst...

Assessing indoor air quality options: Final environmental impact statement on new energy-efficient home programs: Volume 2

International Nuclear Information System (INIS)

1988-03-01

This report discusses the impact of energy conservation measures on indoor air quality in various size residential buildings. This volume includes appendices on ventilation rates, indoor pollutant levels, health effects, human risk assessment, radon, fiberglass hazards, tobacco smoke, mitigation

Indoor air quality of everyday use spaces dedicated to specific purposes-a review.

Science.gov (United States)

Marć, Mariusz; Śmiełowska, Monika; Namieśnik, Jacek; Zabiegała, Bożena

2018-01-01

According to literature data, some of the main factors which significantly affect the quality of the indoor environment in residential households or apartments are human activities such as cooking, smoking, cleaning, and indoor exercising. The paper presents a literature overview related to air quality in everyday use spaces dedicated to specific purposes which are integral parts of residential buildings, such as kitchens, basements, and individual garages. Some aspects of air quality in large-scale car parks, as a specific type of indoor environment, are also discussed. All those areas are characterized by relatively short time use. On the other hand, high and very high concentration levels of xenobiotics can be observed, resulting in higher exposure risk. The main compounds or group of chemical compounds are presented and discussed. The main factors influencing the type and amount of chemical pollutants present in the air of such areas are indicated.

Development of Indoor Air Pollution Concentration Prediction by Geospatial Analysis

Directory of Open Access Journals (Sweden)

Adyati Pradini Yudison

2015-07-01

Full Text Available People living near busy roads are potentially exposed to traffic-induced air pollutants. The pollutants may intrude into the indoor environment, causing health risks to the occupants. Prediction of pollutant exposure therefore is of great importance for impact assessment and policy making related to environmentally sustainable transport. This study involved the selection of spatial interpolation methods that can be used for prediction of indoor air quality based on outdoor pollutant mapping without indoor measurement data. The research was undertaken in the densely populated area of Karees, Bandung, Indonesia. The air pollutant NO2 was monitored in this area as a preliminary study. Nitrogen dioxide concentrations were measured by passive diffusion tube. Outdoor NO2 concentrations were measured at 94 locations, consisting of 30 roadside and 64 outdoor locations. Residential indoor NO2 concentrations were measured at 64 locations. To obtain a spatially continuous air quality map, the spatial interpolation methods of inverse distance weighting (IDW and Kriging were applied. Selection of interpolation method was done based on the smallest root mean square error (RMSE and standard deviation (SD. The most appropriate interpolation method for outdoor NO2 concentration mapping was Kriging with an SD value of 5.45 µg/m3 and an RMSE value of 5.45 µg/m3, while for indoor NO2 concentration mapping the IDW was best fitted with an RMSE value of 5.92 µg/m3 and an SD value of 5.92 µg/m3.

Improving Wi-Fi Based Indoor Positioning Using Bluetooth Add-Ons

DEFF Research Database (Denmark)

Baniukevic, Artur; Sabonis, Dovydas; Jensen, Christian S.

2011-01-01

enabling indoor LBSs. Existing indoor positioning services typically use a single technology such as Wi-Fi, RFID or Bluetooth. Wi-Fi based indoor positioning is relatively easy to deploy, but does often not offer good positioning accuracy. In contrast, the use of RFID or Bluetooth for positioning requires...... considerable investments in equipment in order to ensure good positioning accuracy. Motivated by these observations, we propose a hybrid approach to indoor positioning. In particular, we introduce Bluetooth hotspots into an indoor space with an existing Wi-Fi infrastructure such that better positioning...

Assessment of Natural Ventilation Potential for Residential Buildings across Different Climate Zones in Australia

Directory of Open Access Journals (Sweden)

Zijing Tan

2017-09-01

Full Text Available In this study, the natural ventilation potential of residential buildings was numerically investigated based on a typical single-story house in the three most populous climate zones in Australia. Simulations using the commercial simulation software TRNSYS (Transient System Simulation Tool were performed for all seasons in three representative cities, i.e., Darwin for the hot humid summer and warm winter zone, Sydney for the mild temperate zone, and Melbourne for the cool temperate zone. A natural ventilation control strategy was generated by the rule-based decision-tree method based on the local climates. Natural ventilation hour (NVH and satisfied natural ventilation hour (SNVH were employed to evaluate the potential of natural ventilation in each city considering local climate and local indoor thermal comfort requirements, respectively. The numerical results revealed that natural ventilation potential was related to the local climate. The greatest natural ventilation potential for the case study building was observed in Darwin with an annual 4141 SNVH out of 4728 NVH, while the least natural ventilation potential was found in the Melbourne case. Moreover, summer and transition seasons (spring and autumn were found to be the optimal periods to sustain indoor thermal comfort by utilising natural ventilation in Sydney and Melbourne. By contrast, natural ventilation was found applicable over the whole year in Darwin. In addition, the indoor operative temperature results demonstrated that indoor thermal comfort can be maintained only by utilising natural ventilation for all cases during the whole year, except for the non-natural ventilation periods in summer in Darwin and winter in Melbourne. These findings could improve the understanding of natural ventilation potential in different climates, and are beneficial for the climate-conscious design of residential buildings in Australia.

Supporting Indoor Navigation Using Access Rights to Spaces Based on Combined Use of IndoorGML and LADM Models

Directory of Open Access Journals (Sweden)

Abdullah Alattas

2017-11-01

Full Text Available The aim of this research is to investigate the combined use of IndoorGML and the Land Administration Domain Model (LADM to define the accessibility of the indoor spaces based on the ownership and/or the functional right for use. The users of the indoor spaces create a relationship with the space depending on the type of the building and the function of the spaces. The indoor spaces of each building have different usage functions and associated users. By defining the user types of the indoor spaces, LADM makes it possible to establish a relationship between the indoor spaces and the users. LADM assigns rights, restrictions, and responsibilities to each indoor space, which indicates the accessible spaces for each type of user. The three-dimensional (3D geometry of the building will be impacted by assigning such functional rights, and will provide additional knowledge to path computation for an individual or a group of users. As a result, the navigation process will be more appropriate and simpler because the navigation path will avoid all of the non-accessible spaces based on the rights of the party. The combined use of IndoorGML and LADM covers a broad range of information classes: (indoor 3D cell spaces, connectivity, spatial units/boundaries, (access/use rights and restrictions, parties/persons/actors, and groups of them. The new specialized classes for individual students, individual staff members, groups of students, groups of staff members are able to represent cohorts of education programmes and the organizational structure (organogram: faculty, department, group. The model is capable to represent the access times to lecture rooms (based on education/teaching schedules, use rights of meeting rooms, opening hours of offices, etc. The two original standard models remain independent in our approach, we do not propose yet another model, but applications can fully benefit of the potential of the combined use, which is an important contribution

Determining magmatic series and oxygen fugacity of volcanic rocks in the east of Kamu, north of Isfahan, based on biotite chemistry

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Mohammad Sayari

2014-04-01

Full Text Available Volcanic rocks of interest are situated in the middle part of the Urumieh-Dokhtar Magmatic Arc (UDMA. They are parts of a vast magmatic province located in the north of Bitlis-Zagros suture zone. Having a prevailing porphyritic texture, these rocks include phenocrysts of plagioclase, amphibole and biotite in a matrix composed of feldspar, quartz, opaque, glass and microlite and mineralogically show composition of dacite to andesite. Minerals are mostly fresh. Effects of alteration are limited to weak chloritization and saussuritization in some amphiboles and rim of plagioclases, respectively. All of the analyzed biotites in the Miocene-Pliocene volcanic rocks in the east of Kamu are of Mg-biotite. According to a widespread classification of micas to 6 general end-members, biotites of interest are averagely composed of 55.45% phlogopite, 15.90% talc, 12.72% Ti-phlogopite, 11.44% eastonite, 3.71% ferri-eastonite and 0.78% muscovite. Chemical composition of biotites indicates a calk-alkaline magmatic series for the magma from which biotites are crystallized. Estimation of the oxygen fugacity of magma, based on chemical composition and Fe3+ content of biotite, shows that the oxygen fugacity was limited to FMQ buffer in quality and was about 10-15 bar in quantity. This value accords the oxygen fugacity for intermediate-acidic volcanic rocks.

Improved spring model-based collaborative indoor visible light positioning

Science.gov (United States)

Luo, Zhijie; Zhang, WeiNan; Zhou, GuoFu

2016-06-01

Gaining accuracy with indoor positioning of individuals is important as many location-based services rely on the user's current position to provide them with useful services. Many researchers have studied indoor positioning techniques based on WiFi and Bluetooth. However, they have disadvantages such as low accuracy or high cost. In this paper, we propose an indoor positioning system in which visible light radiated from light-emitting diodes is used to locate the position of receivers. Compared with existing methods using light-emitting diode light, we present a high-precision and simple implementation collaborative indoor visible light positioning system based on an improved spring model. We first estimate coordinate position information using the visible light positioning system, and then use the spring model to correct positioning errors. The system can be employed easily because it does not require additional sensors and the occlusion problem of visible light would be alleviated. We also describe simulation experiments, which confirm the feasibility of our proposed method.

Urinary Pyrethroid and Chlorpyrifos Metabolite Concentraitons in Northern California families and their relationship to indoor home insecticide levels, part of the Study of Use of Products and Exposure Related Behavior (SUPERB)

Science.gov (United States)

Since the 2001 U.S. federally mandated phase-out of residential uses of organophosphate (OP) insecticides, the use of and potential for human exposure to pyrethroid insecticides in the indoor residential environment increases, while that for OPs decreases. Here we report indoor ...

Ventilation, indoor air quality, and health in homes undergoing weatherization.

Science.gov (United States)

Francisco, P W; Jacobs, D E; Targos, L; Dixon, S L; Breysse, J; Rose, W; Cali, S

2017-03-01

Ventilation standards, health, and indoor air quality have not been adequately examined for residential weatherization. This randomized trial showed how ASHRAE 62-1989 (n=39 houses) and ASHRAE 62.2-2010 (n=42 houses) influenced ventilation rates, moisture balance, indoor air quality, and self-reported physical and mental health outcomes. Average total airflow was nearly twice as high for ASHRAE 62.2-2010 (79 vs. 39 cfm). Volatile organic compounds, formaldehyde and carbon dioxide were all significantly reduced for the newer standard and first-floor radon was marginally lower, but for the older standard, only formaldehyde significantly decreased. Humidity in the ASHRAE 62.2-2010 group was only about half that of the ASHRAE 62-1989 group using the moisture balance metric. Radon was higher in the basement but lower on the first floor for ASHRAE 62.2-2010. Children in each group had fewer headaches, eczema, and skin allergies after weatherization and adults had improvements in psychological distress. Indoor air quality and health improve when weatherization is accompanied by an ASHRAE residential ventilation standard, and the 2010 ASHRAE standard has greater improvements in certain outcomes compared to the 1989 standard. Weatherization, home repair, and energy conservation projects should use the newer ASHRAE standard to improve indoor air quality and health. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Investigation of indoor air quality at residential homes in Hong Kong - case study

International Nuclear Information System (INIS)

Shun Cheng Lee; Waiming Li; Chiohang Ao

2002-01-01

Indoor air quality (IAQ) has been a matter of public concern in Hong Kong. Recently, the Hong Kong Government has recognized the potential risk and problems related to indoor air pollution, and it is striving to establish IAQ objectives for different types of indoor environments. This study attempts to provide more information about the present IAQ of local resident flats. Air pollutants measured in this study included carbon dioxide (CO 2 ), respirable suspended particulate matter (PM 10 ), formaldehyde (HCHO), volatile organic compounds (VOCs) and airborne bacteria. The results of this study indicate that the 8-h average concentrations of CO 2 and PM 10 in the domestic kitchens investigated were 14% and 67% higher than those measured in the living rooms. The indoor air pollution caused by PM 10 was more serious in domestic kitchens than in living rooms as almost all of the kitchens investigated had higher indoor levels of PM 10 . The majority of the domestic living rooms and kitchens studied had average concentrations of airborne bacteria higher than 500CFU/m 3 . The mean total bacteria count recorded in kitchens was greater than that obtained in living rooms by 23%. In homes where occupants smoke, the negative impact of benzene, toluene and m,p-xylene on the IAQ was greatly enhanced. The use of liquefied petroleum gas (LPG) stove has more significant impact on indoor VOCs than the use of cooking stoves with natural gas as cooking fuel. (Author)

Sampling strategies for indoor radon investigations

International Nuclear Information System (INIS)

Prichard, H.M.

1983-01-01

Recent investigations prompted by concern about the environmental effects of residential energy conservation have produced many accounts of indoor radon concentrations far above background levels. In many instances time-normalized annual exposures exceeded the 4 WLM per year standard currently used for uranium mining. Further investigations of indoor radon exposures are necessary to judge the extent of the problem and to estimate the practicality of health effects studies. A number of trends can be discerned as more indoor surveys are reported. It is becoming increasingly clear that local geological factors play a major, if not dominant role in determining the distribution of indoor radon concentrations in a given area. Within a giving locale, indoor radon concentrations tend to be log-normally distributed, and sample means differ markedly from one region to another. The appreciation of geological factors and the general log-normality of radon distributions will improve the accuracy of population dose estimates and facilitate the design of preliminary health effects studies. The relative merits of grab samples, short and long term integrated samples, and more complicated dose assessment strategies are discussed in the context of several types of epidemiological investigations. A new passive radon sampler with a 24 hour integration time is described and evaluated as a tool for pilot investigations

VLC-based indoor location awareness using LED light and image sensors

Science.gov (United States)

Lee, Seok-Ju; Yoo, Jong-Ho; Jung, Sung-Yoon

2012-11-01

Recently, indoor LED lighting can be considered for constructing green infra with energy saving and additionally providing LED-IT convergence services such as visible light communication (VLC) based location awareness and navigation services. For example, in case of large complex shopping mall, location awareness to navigate the destination is very important issue. However, the conventional navigation using GPS is not working indoors. Alternative location service based on WLAN has a problem that the position accuracy is low. For example, it is difficult to estimate the height exactly. If the position error of the height is greater than the height between floors, it may cause big problem. Therefore, conventional navigation is inappropriate for indoor navigation. Alternative possible solution for indoor navigation is VLC based location awareness scheme. Because indoor LED infra will be definitely equipped for providing lighting functionality, indoor LED lighting has a possibility to provide relatively high accuracy of position estimation combined with VLC technology. In this paper, we provide a new VLC based positioning system using visible LED lights and image sensors. Our system uses location of image sensor lens and location of reception plane. By using more than two image sensor, we can determine transmitter position less than 1m position error. Through simulation, we verify the validity of the proposed VLC based new positioning system using visible LED light and image sensors.

Coordinate-Based Clustering Method for Indoor Fingerprinting Localization in Dense Cluttered Environments

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Wen Liu

2016-12-01

Full Text Available Indoor positioning technologies has boomed recently because of the growing commercial interest in indoor location-based service (ILBS. Due to the absence of satellite signal in Global Navigation Satellite System (GNSS, various technologies have been proposed for indoor applications. Among them, Wi-Fi fingerprinting has been attracting much interest from researchers because of its pervasive deployment, flexibility and robustness to dense cluttered indoor environments. One challenge, however, is the deployment of Access Points (AP, which would bring a significant influence on the system positioning accuracy. This paper concentrates on WLAN based fingerprinting indoor location by analyzing the AP deployment influence, and studying the advantages of coordinate-based clustering compared to traditional RSS-based clustering. A coordinate-based clustering method for indoor fingerprinting location, named Smallest-Enclosing-Circle-based (SEC, is then proposed aiming at reducing the positioning error lying in the AP deployment and improving robustness to dense cluttered environments. All measurements are conducted in indoor public areas, such as the National Center For the Performing Arts (as Test-bed 1 and the XiDan Joy City (Floors 1 and 2, as Test-bed 2, and results show that SEC clustering algorithm can improve system positioning accuracy by about 32.7% for Test-bed 1, 71.7% for Test-bed 2 Floor 1 and 73.7% for Test-bed 2 Floor 2 compared with traditional RSS-based clustering algorithms such as K-means.

Coordinate-Based Clustering Method for Indoor Fingerprinting Localization in Dense Cluttered Environments.

Science.gov (United States)

Liu, Wen; Fu, Xiao; Deng, Zhongliang

2016-12-02

Indoor positioning technologies has boomed recently because of the growing commercial interest in indoor location-based service (ILBS). Due to the absence of satellite signal in Global Navigation Satellite System (GNSS), various technologies have been proposed for indoor applications. Among them, Wi-Fi fingerprinting has been attracting much interest from researchers because of its pervasive deployment, flexibility and robustness to dense cluttered indoor environments. One challenge, however, is the deployment of Access Points (AP), which would bring a significant influence on the system positioning accuracy. This paper concentrates on WLAN based fingerprinting indoor location by analyzing the AP deployment influence, and studying the advantages of coordinate-based clustering compared to traditional RSS-based clustering. A coordinate-based clustering method for indoor fingerprinting location, named Smallest-Enclosing-Circle-based (SEC), is then proposed aiming at reducing the positioning error lying in the AP deployment and improving robustness to dense cluttered environments. All measurements are conducted in indoor public areas, such as the National Center For the Performing Arts (as Test-bed 1) and the XiDan Joy City (Floors 1 and 2, as Test-bed 2), and results show that SEC clustering algorithm can improve system positioning accuracy by about 32.7% for Test-bed 1, 71.7% for Test-bed 2 Floor 1 and 73.7% for Test-bed 2 Floor 2 compared with traditional RSS-based clustering algorithms such as K-means.

Field Measurement and Evaluation of the Passive and Active Solar Heating Systems for Residential Building Based on the Qinghai-Tibetan Plateau Case

Directory of Open Access Journals (Sweden)

Zhijian Liu

2017-10-01

Full Text Available Passive and active solar heating systems have drawn much attention and are widely used in residence buildings in the Qinghai-Tibetan plateau due to its high radiation intensity. In fact, there is still lack of quantitative evaluation of the passive and active heating effect, especially for residential building in the Qinghai-Tibetan plateau areas. In this study, three kinds of heating strategies, including reference condition, passive solar heating condition and active solar heating condition, were tested in one demonstration residential building. The hourly air temperatures of each room under different conditions were obtained and analyzed. The results show the indoor air temperature in the living room and bedrooms (core zones was much higher than that of other rooms under both passive and active solar heating conditions. In addition, the heating effect with different strategies for core zones of the building was evaluated by the ratio of indoor and outdoor degree hour, which indicates that solar heating could effectively reduce the traditional energy consumption and improve the indoor thermal environment. The passive solar heating could undertake 49.8% degree hours for heating under an evaluation criterion of 14 °C and the active solar heating could undertake 75% degree hours for heating under evaluation criterion of 18 °C, which indicated that solar heating could effectively reduce the traditional energy consumption and improve the indoor thermal environment in this area. These findings could provide reference for the design and application of solar heating in similar climate areas.

Measure Guideline: Combustion Safety for Natural Draft Appliances Using Indoor Air

Energy Technology Data Exchange (ETDEWEB)

Brand, L.

2014-04-01

This measure guideline covers how to assess and carry out the combustion safety procedures for appliances and heating equipment that uses indoor air for combustion in low-rise residential buildings. Only appliances installed in the living space, or in an area freely communicating with the living space, vented alone or in tandem with another appliance are considered here. A separate measure guideline addresses combustion appliances located either within the living space in enclosed closets or side rooms or outside the living space in an adjacent area like an attic or garage that use outdoor air for combustion. This document is for inspectors, auditors, and technicians working in homes where energy upgrades are being conducted whether or not air infiltration control is included in the package of measures being applied. In the indoor combustion air case, guidelines summarized here are based on language provided in several of the codes to establish minimum requirements for the space using simplified prescriptive measures. In addition, building performance testing procedures are provided by testing agencies. The codes in combination with the test procedures offer comprehensive combustion safety coverage to address safety concerns, allowing inexperienced residential energy retrofit inspectors to effectively address combustion safety issues and allow energy retrofits to proceed.

Comparison of Indoor Mercury Vapor in Common Areas of Residential Buildings with Outdoor Levels in a Community Where Mercury Is Used for Cultural Purposes

Science.gov (United States)

Garetano, Gary; Gochfeld, Michael; Stern, Alan H.

2006-01-01

Elemental mercury has been imbued with magical properties for millennia, and various cultures use elemental mercury in a variety of superstitious and cultural practices, raising health concerns for users and residents in buildings where it is used. As a first step in assessing this phenomenon, we compared mercury vapor concentration in common areas of residential buildings versus outdoor air, in two New Jersey cities where mercury is available and is used in cultural practices. We measured mercury using a portable atomic absorption spectrometer capable of quantitative measurement from 2 ng/m3 mercury vapor. We evaluated the interior hallways in 34 multifamily buildings and the vestibule in an additional 33 buildings. Outdoor mercury vapor averaged 5 ng/m3; indoor mercury was significantly higher (mean 25 ng/m3; p < 0.001); 21% of buildings had mean mercury vapor concentration in hallways that exceeded the 95th percentile of outdoor mercury vapor concentration (17 ng/m3), whereas 35% of buildings had a maximum mercury vapor concentration that exceeded the 95th percentile of outdoor mercury concentration. The highest indoor average mercury vapor concentration was 299 ng/m3, and the maximum point concentration was 2,022 ng/m3. In some instances, we were able to locate the source, but we could not specifically attribute the elevated levels of mercury vapor to cultural use or other specific mercury releases. However, these findings provide sufficient evidence of indoor mercury source(s) to warrant further investigation. PMID:16393659

Barcode based localization system in indoor environment

Directory of Open Access Journals (Sweden)

Ľubica Ilkovičová

2014-12-01

Full Text Available Nowadays, in the era of intelligent buildings, there is a need to create indoornavigation systems, what is steadily a challenge. QR (Quick Response codesprovide accurate localization also in indoor environment, where other navigationtechniques (e.g. GPS are not available. The paper deals with the issues of posi-tioning using QR codes, solved at the Department of Surveying, Faculty of CivilEngineering SUT in Bratislava. Operating principle of QR codes, description ofthe application for positioning in indoor environment based on OS Android forsmartphones are described.

Particulate Matter Mass Concentration in Residential Prefabricated Buildings Related to Temperature and Moisture

Science.gov (United States)

Kraus, Michal; Juhásová Šenitková, Ingrid

2017-10-01

Building environmental audit and the assessment of indoor air quality (IAQ) in typical residential buildings is necessary process to ensure users’ health and well-being. The paper deals with the concentrations on indoor dust particles (PM10) in the context of hygrothermal microclimate in indoor environment. The indoor temperature, relative humidity and air movement are basic significant factors determining the PM10 concentration [μg/m3]. The experimental measurements in this contribution represent the impact of indoor physical parameters on the concentration of particulate matter mass concentration. The occurrence of dust particles is typical for the almost two-thirds of interiors of the buildings. Other parameters indoor environment, such as air change rate, volume of the room, roughness and porosity of the building material surfaces, static electricity, light ions and others, were set constant and they are not taken into account in this study. The mass concentration of PM10 is measured during summer season in apartment of residential prefabricated building. The values of global temperature [°C] and relative humidity of indoor air [%] are also monitored. The quantity of particulate mass matter is determined gravimetrically by weighing according to CSN EN 12 341 (2014). The obtained results show that the temperature difference of the internal environment does not have a significant effect on the concentration PM10. Vice versa, the difference of relative humidity exhibits a difference of the concentration of dust particles. Higher levels of indoor particulates are observed for low values of relative humidity. The decreasing of relative air humidity about 10% caused 10µg/m3 of PM10 concentration increasing. The hygienic limit value of PM10 concentration is not exceeded at any point of experimental measurement.

Development of a Residential Integrated Ventilation Controller

Energy Technology Data Exchange (ETDEWEB)

Staff Scientist; Walker, Iain; Sherman, Max; Dickerhoff, Darryl

2011-12-01

The goal of this study was to develop a Residential Integrated Ventilation Controller (RIVEC) to reduce the energy impact of required mechanical ventilation by 20percent, maintain or improve indoor air quality and provide demand response benefits. This represents potential energy savings of about 140 GWh of electricity and 83 million therms of natural gas as well as proportional peak savings in California. The RIVEC controller is intended to meet the 2008 Title 24 requirements for residential ventilation as well as taking into account the issues of outdoor conditions, other ventilation devices (including economizers), peak demand concerns and occupant preferences. The controller is designed to manage all the residential ventilation systems that are currently available. A key innovation in this controller is the ability to implement the concept of efficacy and intermittent ventilation which allows time shifting of ventilation. Using this approach ventilation can be shifted away from times of high cost or high outdoor pollution towards times when it is cheaper and more effective. Simulations, based on the ones used to develop the new residential ventilation requirements for the California Buildings Energy code, were used to further define the specific criteria and strategies needed for the controller. These simulations provide estimates of the energy, peak power and contaminant improvement possible for different California climates for the various ventilation systems. Results from a field test of the prototype controller corroborate the predicted performance.

Maximum Regional Emission Reduction Potential in Residential Sector Based on Spatial Distribution of Population and Resources

Science.gov (United States)

Winijkul, E.; Bond, T. C.

2011-12-01

In the residential sector, major activities that generate emissions are cooking and heating, and fuels ranging from traditional (wood) to modern (natural gas, or electricity) are used. Direct air pollutant emissions from this sector are low when natural gas or electricity are the dominant energy sources, as is the case in developed countries. However, in developing countries, people may rely on solid fuels and this sector can contribute a large fraction of emissions. The magnitude of the health loss associated with exposure to indoor smoke as well as its concentration among rural population in developing countries have recently put preventive measures high on the agenda of international development and public health organizations. This study focuses on these developing regions: Central America, Africa, and Asia. Current and future emissions from the residential sector depend on both fuel and cooking device (stove) type. Availability of fuels, stoves, and interventions depends strongly on spatial distribution. However, regional emission calculations do not consider this spatial dependence. Fuel consumption data is presented at country level, without information about where different types of fuel are used. Moreover, information about stove types that are currently used and can be used in the future is not available. In this study, we first spatially allocate current emissions within residential sector. We use Geographic Information System maps of temperature, electricity availability, forest area, and population to determine the distribution of fuel types and availability of stoves. Within each country, consumption of different fuel types, such as fuelwood, coal, and LPG is distributed among different area types (urban, peri-urban, and rural area). Then, the cleanest stove technologies which could be used in the area are selected based on the constraints of each area, i.e. availability of resources. Using this map, the maximum emission reduction compared with

Privacy vs. Reward in Indoor Location-Based Services

Directory of Open Access Journals (Sweden)

Fawaz Kassem

2016-10-01

Full Text Available With the advance of indoor localization technology, indoor location-based services (ILBS are gaining popularity. They, however, accompany privacy concerns. ILBS providers track the users’ mobility to learn more about their behavior, and then provide them with improved and personalized services. Our survey of 200 individuals highlighted their concerns about this tracking for potential leakage of their personal/private traits, but also showed their willingness to accept reduced tracking for improved service. In this paper, we propose PR-LBS (Privacy vs. Reward for Location-Based Service, a system that addresses these seemingly conflicting requirements by balancing the users’ privacy concerns and the benefits of sharing location information in indoor location tracking environments. PR-LBS relies on a novel location-privacy criterion to quantify the privacy risks pertaining to sharing indoor location information. It also employs a repeated play model to ensure that the received service is proportionate to the privacy risk. We implement and evaluate PR-LBS extensively with various real-world user mobility traces. Results show that PR-LBS has low overhead, protects the users’ privacy, and makes a good tradeoff between the quality of service for the users and the utility of shared location data for service providers.

Indoor radon monitoring in the Mandi district of Himachal Pradesh, India, for health hazard assessment

International Nuclear Information System (INIS)

Kumar, G.; Kumar, A.; Walia, V.; Kumar, M.; Tuccu, M.A.; Prasher, S.

2016-01-01

In the present study, indoor radon equilibrium equivalent concentration monitoring was carried out using Solid-State Nuclear Track Detectors in some residential areas of the Mandi district, Himachal Pradesh, India. The average value of the indoor radon equilibrium equivalent concentration in the study area was found to be 94 Bq m -3 , with an annual effective dose of 1.61 mSv. The average value of the indoor radon equilibrium equivalent concentration in the studied areas was found to be higher than the world average indoor radon value of 40 Bq m -3 but lower than the value of the action level 300 Bq m -3 , except for two locations. (authors)

The Spanish indoor radon mapping strategy

International Nuclear Information System (INIS)

Sainz-Fernandez, C.; Fernandez-Villar, A.; Fuente-Merino, I.; Gutierrez-Villanueva, J.L.; Casal-Ordas, S.; Quindos-Poncela, L.S.; Martin-Matarranz, J.L.; Garcia-Talavera, M.

2014-01-01

Indoor radon mapping still represents a valuable tool for drawing the picture of the exposure of general public due to radon and radon progeny inhalation in a residential context. The information provided by means of a map is useful not only as awareness and strategic element for authorities and policy-makers, but also as a scientific start-up point in the design of epidemiological and other specific studies on exposure to natural radiation. The requirements for a good mapping are related to harmonisation criteria coming from European recommendations, as well as to national/local characteristics and necessities. Around 12 000 indoor radon measurements have been made since the Spanish national radon programme began at the end of the 1980's. A significant proportion of them resulted from the last campaign performed from 2009 to 12. This campaign completed the first version of a map based on a grid 10 x 10 km 2 . In this paper, the authors present the main results of a new map together with the criteria adopted to improve the number of measurements and the statistical significance of them. (authors)

Sample size determination algorithm for fingerprint-based indoor localization systems

NARCIS (Netherlands)

Kanaris, L.; Kokkinis, A.; Fortino, G.; Liotta, A.; Stavrou, S.

2016-01-01

Provision of accurate location information is an important task in the Internet of Things (IoT) applications and scenarios. This need has boosted the research and development of fingerprint based, indoor localization systems, since GPS information is not available in indoor environments. Performance

Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

Energy Technology Data Exchange (ETDEWEB)

Martin, Eric [Building Science Corporation, Westford, MA (United States)

2014-01-01

Optimizing whole house mechanical ventilation as part of the Building Ameerica program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this report is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

CSI Frequency Domain Fingerprint-Based Passive Indoor Human Detection

Directory of Open Access Journals (Sweden)

Chong Han

2018-04-01

Full Text Available Passive indoor personnel detection technology is now a hot topic. Existing methods have been greatly influenced by environmental changes, and there are problems with the accuracy and robustness of detection. Passive personnel detection based on Wi-Fi not only solves the above problems, but also has the advantages of being low cost and easy to implement, and can be better applied to elderly care and safety monitoring. In this paper, we propose a passive indoor personnel detection method based on Wi-Fi, which we call FDF-PIHD (Frequency Domain Fingerprint-based Passive Indoor Human Detection. Through this method, fine-grained physical layer Channel State Information (CSI can be extracted to generate feature fingerprints so as to help determine the state in the scene by matching online fingerprints with offline fingerprints. In order to improve accuracy, we combine the detection results of three receiving antennas to obtain the final test result. The experimental results show that the detection rates of our proposed scheme all reach above 90%, no matter whether the scene is human-free, stationary or a moving human presence. In addition, it can not only detect whether there is a target indoors, but also determine the current state of the target.

Changes of indoor climate by the adoption of retrofitted wood-burning stoves

DEFF Research Database (Denmark)

Luis Teles de Carvalho, Ricardo; Jensen, Ole Michael; Tarelho, Luis A. C.

2014-01-01

More than 3 billion people in the world rely on local solid-fuels for domestic cooking and heating through inefficient combustion, causing indoor air pollution and overheating worldwide. Technological regimes were categorized in 18 popular stove models to describe how residential wood combustion ...

Prospective future introduction of reduction of energy use in buildings in the Arctic regions – How might it affect the indoor climate?

DEFF Research Database (Denmark)

Vladyková, Petra; Bjarløv, Søren Peter

Existing residential buildings in Arctic Greenland often have problems with draughts, uncomfortably low temperatures indoors, and inadequate ventilation. The standard wooden house 18D provides low thermal comfort and poor indoor air quality and has high energy consumption. On the other hand...

RESEARCH ON KNOWLEDGE-BASED OPTIMIZATION METHOD OF INDOOR LOCATION BASED ON LOW ENERGY BLUETOOTH

Directory of Open Access Journals (Sweden)

C. Li

2017-09-01

Full Text Available With the rapid development of LBS (Location-based Service, the demand for commercialization of indoor location has been increasing, but its technology is not perfect. Currently, the accuracy of indoor location, the complexity of the algorithm, and the cost of positioning are hard to be simultaneously considered and it is still restricting the determination and application of mainstream positioning technology. Therefore, this paper proposes a method of knowledge-based optimization of indoor location based on low energy Bluetooth. The main steps include: 1 The establishment and application of a priori and posterior knowledge base. 2 Primary selection of signal source. 3 Elimination of positioning gross error. 4 Accumulation of positioning knowledge. The experimental results show that the proposed algorithm can eliminate the signal source of outliers and improve the accuracy of single point positioning in the simulation data. The proposed scheme is a dynamic knowledge accumulation rather than a single positioning process. The scheme adopts cheap equipment and provides a new idea for the theory and method of indoor positioning. Moreover, the performance of the high accuracy positioning results in the simulation data shows that the scheme has a certain application value in the commercial promotion.

Research on Knowledge-Based Optimization Method of Indoor Location Based on Low Energy Bluetooth

Science.gov (United States)

Li, C.; Li, G.; Deng, Y.; Wang, T.; Kang, Z.

2017-09-01

With the rapid development of LBS (Location-based Service), the demand for commercialization of indoor location has been increasing, but its technology is not perfect. Currently, the accuracy of indoor location, the complexity of the algorithm, and the cost of positioning are hard to be simultaneously considered and it is still restricting the determination and application of mainstream positioning technology. Therefore, this paper proposes a method of knowledge-based optimization of indoor location based on low energy Bluetooth. The main steps include: 1) The establishment and application of a priori and posterior knowledge base. 2) Primary selection of signal source. 3) Elimination of positioning gross error. 4) Accumulation of positioning knowledge. The experimental results show that the proposed algorithm can eliminate the signal source of outliers and improve the accuracy of single point positioning in the simulation data. The proposed scheme is a dynamic knowledge accumulation rather than a single positioning process. The scheme adopts cheap equipment and provides a new idea for the theory and method of indoor positioning. Moreover, the performance of the high accuracy positioning results in the simulation data shows that the scheme has a certain application value in the commercial promotion.

Evaluating fugacity models for trace components in landfill gas

Energy Technology Data Exchange (ETDEWEB)

Shafi, Sophie [Integrated Waste Management Centre, Sustainable Systems Department, Building 61, School of Industrial and Manufacturing Science, Cranfield University, Cranfield, Bedfordshire MK43 0AL (United Kingdom); Sweetman, Andrew [Department of Environmental Science, Lancaster University, Lancaster LA1 4YQ (United Kingdom); Hough, Rupert L. [Integrated Waste Management Centre, Sustainable Systems Department, Building 61, School of Industrial and Manufacturing Science, Cranfield University, Cranfield, Bedfordshire MK43 0AL (United Kingdom); Smith, Richard [Integrated Waste Management Centre, Sustainable Systems Department, Building 61, School of Industrial and Manufacturing Science, Cranfield University, Cranfield, Bedfordshire MK43 0AL (United Kingdom); Rosevear, Alan [Science Group - Waste and Remediation, Environment Agency, Reading RG1 8DQ (United Kingdom); Pollard, Simon J.T. [Integrated Waste Management Centre, Sustainable Systems Department, Building 61, School of Industrial and Manufacturing Science, Cranfield University, Cranfield, Bedfordshire MK43 0AL (United Kingdom)]. E-mail: s.pollard@cranfield.ac.uk

2006-12-15

A fugacity approach was evaluated to reconcile loadings of vinyl chloride (chloroethene), benzene, 1,3-butadiene and trichloroethylene in waste with concentrations observed in landfill gas monitoring studies. An evaluative environment derived from fictitious but realistic properties such as volume, composition, and temperature, constructed with data from the Brogborough landfill (UK) test cells was used to test a fugacity approach to generating the source term for use in landfill gas risk assessment models (e.g. GasSim). SOILVE, a dynamic Level II model adapted here for landfills, showed greatest utility for benzene and 1,3-butadiene, modelled under anaerobic conditions over a 10 year simulation. Modelled concentrations of these components (95 300 {mu}g m{sup -3}; 43 {mu}g m{sup -3}) fell within measured ranges observed in gas from landfills (24 300-180 000 {mu}g m{sup -3}; 20-70 {mu}g m{sup -3}). This study highlights the need (i) for representative and time-referenced biotransformation data; (ii) to evaluate the partitioning characteristics of organic matter within waste systems and (iii) for a better understanding of the role that gas extraction rate (flux) plays in producing trace component concentrations in landfill gas. - Fugacity for trace component in landfill gas.

A Generalized Model for Indoor Location Estimation Using Environmental Sound from Human Activity Recognition

Directory of Open Access Journals (Sweden)

Carlos E. Galván-Tejada

2018-02-01

Full Text Available The indoor location of individuals is a key contextual variable for commercial and assisted location-based services and applications. Commercial centers and medical buildings (e.g., hospitals require location information of their users/patients to offer the services that are needed at the correct moment. Several approaches have been proposed to tackle this problem. In this paper, we present the development of an indoor location system which relies on the human activity recognition approach, using sound as an information source to infer the indoor location based on the contextual information of the activity that is realized at the moment. In this work, we analyze the sound information to estimate the location using the contextual information of the activity. A feature extraction approach to the sound signal is performed to feed a random forest algorithm in order to generate a model to estimate the location of the user. We evaluate the quality of the resulting model in terms of sensitivity and specificity for each location, and we also perform out-of-bag error estimation. Our experiments were carried out in five representative residential homes. Each home had four individual indoor rooms. Eleven activities (brewing coffee, cooking, eggs, taking a shower, etc. were performed to provide the contextual information. Experimental results show that developing an indoor location system (ILS that uses contextual information from human activities (identified with data provided from the environmental sound can achieve an estimation that is 95% correct.

The diversity and distribution of fungi on residential surfaces.

Directory of Open Access Journals (Sweden)

Rachel I Adams

Full Text Available The predominant hypothesis regarding the composition of microbial assemblages in indoor environments is that fungal assemblages are structured by outdoor air with a moderate contribution by surface growth, whereas indoor bacterial assemblages represent a mixture of bacteria entered from outdoor air, shed by building inhabitants, and grown on surfaces. To test the fungal aspect of this hypothesis, we sampled fungi from three surface types likely to support growth and therefore possible contributors of fungi to indoor air: drains in kitchens and bathrooms, sills beneath condensation-prone windows, and skin of human inhabitants. Sampling was done in replicated units of a university-housing complex without reported mold problems, and sequences were analyzed using both QIIME and the new UPARSE approach to OTU-binning, to the same result. Surfaces demonstrated a mycological profile similar to that of outdoor air from the same locality, and assemblages clustered by surface type. "Weedy" genera typical of indoor air, such as Cladosporium and Cryptococcus, were abundant on sills, as were a diverse set of fungi of likely outdoor origin. Drains supported more depauperate assemblages than the other surfaces and contained thermotolerant genera such as Exophiala, Candida, and Fusarium. Most surprising was the composition detected on residents' foreheads. In addition to harboring Malassezia, a known human commensal, skin also possessed a surprising richness of non-resident fungi, including plant pathogens such as ergot (Claviceps purperea. Overall, fungal richness across indoor surfaces was high, but based on known autecologies, most of these fungi were unlikely to be growing on surfaces. We conclude that while some endogenous fungal growth on typical household surfaces does occur, particularly on drains and skin, all residential surfaces appear - to varying degrees - to be passive collectors of airborne fungi of putative outdoor origin, a view of the origins

Inorganic and carbonaceous components in indoor/outdoor particulate matter in two residential houses in Oslo, Norway.

Science.gov (United States)

Lazaridis, Mihalis; Aleksandropoulou, Victoria; Hanssen, Jan Erik; Dye, Christian; Eleftheriadis, Kostantinos; Katsivela, Eleftheria

2008-03-01

A detailed analysis of indoor/outdoor physicochemical aerosol properties has been performed. Aerosol measurements were taken at two dwellings, one in the city center and the other in the suburbs of the Oslo metropolitan area, during summer/fall and winter/spring periods of 2002-2003. In this paper, emphasis is placed on the chemical characteristics (water-soluble ions and carbonaceous components) of fine (PM2.5) and coarse (PM2.5-10) particles and their indoor/outdoor relationship. Results demonstrate that the carbonaceous species were dominant in all fractions of the PM10 particles (cut off size: 0.09-11.31 microm) during all measurement periods, except winter 2003, when increased concentrations of water-soluble inorganic ions were predominant because of sea salt transport. The concentration of organic carbon was higher in the fine and coarse PM10 fractions indoors, whereas elemental carbon was higher indoors only in the coarse fraction. In regards to the carbonaceous species, local traffic and secondary organic aerosol formation were, probably, the main sources outdoors, whereas indoors combustion activities such as preparation of food, burning of candles, and cigarette smoking were the main sources. In contrast, the concentrations of water-soluble inorganic ions were higher outdoors than indoors. The variability of water-soluble inorganic ion concentrations outdoors was related to changes in emissions from local anthropogenic sources, long-range transport of particles, sea salt emissions, and resuspension of roadside and soil dusts. In the indoor environment the infiltration of the outdoor air indoors was the major source of inorganic ions.

Spatial and indoor/outdoor gradients in urban concentrations of ultrafine particles and PM2.5 mass and chemical components

Science.gov (United States)

Zauli Sajani, Stefano; Ricciardelli, Isabella; Trentini, Arianna; Bacco, Dimitri; Maccone, Claudio; Castellazzi, Silvia; Lauriola, Paolo; Poluzzi, Vanes; Harrison, Roy M.

2015-02-01

In order to investigate relationships between outdoor air pollution and concentrations indoors, a novel design of experiment has been conducted at two sites, one heavily trafficked and the other residential. The novel design aspect involves the introduction of air directly to the centre of an unoccupied room by use of a fan and duct giving a controlled air exchange rate and allowing an evaluation of particle losses purely due to uptake on indoor surfaces without the losses during penetration of the building envelope which affect most measurement programmes. The rooms were unoccupied and free of indoor sources, and consequently reductions in particle concentration were due to deposition processes within the room alone. Measurements were made of indoor and outdoor concentrations of PM2.5, major chemical components and particle number size distributions. Despite the absence of penetration losses, indoor to outdoor ratios were very similar to those in other studies showing that deposition to indoor surfaces is likely to be the major loss process for indoor air. The results demonstrated a dramatic loss of nitrate in the indoor atmosphere as well as a selective loss of particles in the size range below 50 nm, in comparison to coarser particles. Depletion of indoor particles was greater during a period of cold weather with higher outdoor concentrations probably due to an enhancement of semi-volatile materials in the outdoor particulate matter. Indoor/outdoor ratios for PM2.5 were generally higher at the trafficked site than the residential site, but for particle number were generally lower, reflecting the different chemical composition and size distributions of particles at the two sites.

Predicted and actual indoor environmental quality: Verification of occupants' behaviour models in residential buildings

DEFF Research Database (Denmark)

Andersen, Rune Korsholm; Fabi, Valentina; Corgnati, Stefano P.

2016-01-01

with the building controls (windows, thermostats, solar shading etc.). During the last decade, studies about stochastic models of occupants' behaviour in relation to control of the indoor environment have been published. Often the overall aim of these models is to enable more reliable predictions of building...... performance using building energy performance simulations (BEPS). However, the validity of these models has only been sparsely tested. In this paper, stochastic models of occupants' behaviour from literature were tested against measurements in five apartments. In a monitoring campaign, measurements of indoor....... However, comparisons of the average stochastic predictions with the measured temperatures, relative humidity and CO2 concentrations revealed that the models did not predict the actual indoor environmental conditions well....

Working towards residential Radon survey in South America

International Nuclear Information System (INIS)

Zielinski, Jan M.; University of Ottawa, ON; Canoba, Analia C.; Shilnikova, Natalia S.; Veiga, Lene H. S.

2008-01-01

Information about residential radon levels in low and middle income countries is very sparse. In response to the World Health Organization initiative in the International Radon Project, we propose a research project that will address this knowledge gap in South America by conducting a residential radon survey. Following initial in vitro and in vivo studies of radon and studies of uranium miners exposed to radon, over twenty large case-control studies of lung cancer risk from exposure to residential radon have been completed worldwide by year 2004. Recently pooled data from these individual studies have been analyzed. These collaborative analyses of the indoor studies in Europe, North America, and China provide strong direct evidence that radon is causing a substantial number of lung cancers in the general population. To reduce radon lung cancer risk, national authorities must have methods and tools based on solid scientific evidence to develop sound public health policies. We propose to conduct a survey in ten South American countries using the distribution and analysis of passive alpha tracking detectors in houses selected at random in pre-selected cities in each participating country. We also present an approach to estimate the cost of carrying out such a survey and the radon laboratory infrastructure needed. The results of the proposed survey will allow to conduct assessment of the exposure to residential radon in the populations of South American countries and to assess the health impact of this exposure. The results of the project will also help national health authorities in developing national residential radon action levels and regulations, as well as provide public health guidance for radon awareness and mitigation. (author)

Identifying Housing and Meteorological Conditions Influencing Residential Air Exchange Rates in the DEARS and RIOPA Studies: Development of Distributions for Human Exposure Modeling

Science.gov (United States)

Appropriate prediction of residential air exchange rate (AER) is important for estimating human exposures in the residential microenvironment, as AER drives the infiltration of outdoor-generated air pollutants indoors. AER differences among homes may result from a number of fact...

COMBINED EFFECT OF THE AIRBORNE AND IMPACT NOISE PRODUCED ONTO THE SOUND INSULATION OF INSERTED FLOORS OF RESIDENTIAL BUILDINGS: THEORETICAL ASPECTS

Directory of Open Access Journals (Sweden)

Saltykov Ivan Petrovich

2012-10-01

Full Text Available The indoor environment of residential buildings is a complex system. It consists of diverse though related elements. An optimal correlation of parameters of the indoor space converts into the appropriate equilibrium and harmonious human living free from any stimulating or irritating factors that interfere with any working and/or relaxation processes. The author has selected the following three principal factors of the indoor environment. They include heat, daylight and sound. The research has revealed a strong linkn between these factors. Noise pollution of residential houses is taken into account through the introduction of the airborne insulation index and the impact sound index underneath the inserted floor. The findings of theoretical researches and experiments have proven a strong functional relationship between airborne and impact sound values.

The identification of Volatile Organic Compound's emission sources in indoor air of living spaces, offices and laboratories

Science.gov (United States)

Kultys, Beata

2018-01-01

Indoor air quality is important because people spend most of their time in closed rooms. If volatile organic compounds (VOCs) are present at elevated concentrations, they may cause a deterioration in human well-being or health. The identification of indoor emission sources is carried out by comparison indoor and outdoor air composition. The aim of the study was to determinate the concentration of VOCs in indoor air, where there was a risk of elevated levels due to the kind of work type carried out or the users complained about the symptoms of a sick building followed by an appropriate interpretation of the results to determine whether the source of the emission in the tested room occurs. The air from residential, office and laboratory was tested in this study. The identification of emission sources was based on comparison of indoor and outdoor VOCs concentration and their correlation coefficients. The concentration of VOCs in all the rooms were higher or at a similar level to that of the air sampled at the same time outside the building. Human activity, in particular repair works and experiments with organic solvents, has the greatest impact on deterioration of air quality.

MFAM: Multiple Frequency Adaptive Model-Based Indoor Localization Method.

Science.gov (United States)

Tuta, Jure; Juric, Matjaz B

2018-03-24

This paper presents MFAM (Multiple Frequency Adaptive Model-based localization method), a novel model-based indoor localization method that is capable of using multiple wireless signal frequencies simultaneously. It utilizes indoor architectural model and physical properties of wireless signal propagation through objects and space. The motivation for developing multiple frequency localization method lies in the future Wi-Fi standards (e.g., 802.11ah) and the growing number of various wireless signals present in the buildings (e.g., Wi-Fi, Bluetooth, ZigBee, etc.). Current indoor localization methods mostly rely on a single wireless signal type and often require many devices to achieve the necessary accuracy. MFAM utilizes multiple wireless signal types and improves the localization accuracy over the usage of a single frequency. It continuously monitors signal propagation through space and adapts the model according to the changes indoors. Using multiple signal sources lowers the required number of access points for a specific signal type while utilizing signals, already present in the indoors. Due to the unavailability of the 802.11ah hardware, we have evaluated proposed method with similar signals; we have used 2.4 GHz Wi-Fi and 868 MHz HomeMatic home automation signals. We have performed the evaluation in a modern two-bedroom apartment and measured mean localization error 2.0 to 2.3 m and median error of 2.0 to 2.2 m. Based on our evaluation results, using two different signals improves the localization accuracy by 18% in comparison to 2.4 GHz Wi-Fi-only approach. Additional signals would improve the accuracy even further. We have shown that MFAM provides better accuracy than competing methods, while having several advantages for real-world usage.

MFAM: Multiple Frequency Adaptive Model-Based Indoor Localization Method

Directory of Open Access Journals (Sweden)

Jure Tuta

2018-03-01

Full Text Available This paper presents MFAM (Multiple Frequency Adaptive Model-based localization method, a novel model-based indoor localization method that is capable of using multiple wireless signal frequencies simultaneously. It utilizes indoor architectural model and physical properties of wireless signal propagation through objects and space. The motivation for developing multiple frequency localization method lies in the future Wi-Fi standards (e.g., 802.11ah and the growing number of various wireless signals present in the buildings (e.g., Wi-Fi, Bluetooth, ZigBee, etc.. Current indoor localization methods mostly rely on a single wireless signal type and often require many devices to achieve the necessary accuracy. MFAM utilizes multiple wireless signal types and improves the localization accuracy over the usage of a single frequency. It continuously monitors signal propagation through space and adapts the model according to the changes indoors. Using multiple signal sources lowers the required number of access points for a specific signal type while utilizing signals, already present in the indoors. Due to the unavailability of the 802.11ah hardware, we have evaluated proposed method with similar signals; we have used 2.4 GHz Wi-Fi and 868 MHz HomeMatic home automation signals. We have performed the evaluation in a modern two-bedroom apartment and measured mean localization error 2.0 to 2.3 m and median error of 2.0 to 2.2 m. Based on our evaluation results, using two different signals improves the localization accuracy by 18% in comparison to 2.4 GHz Wi-Fi-only approach. Additional signals would improve the accuracy even further. We have shown that MFAM provides better accuracy than competing methods, while having several advantages for real-world usage.

Indoor air humidity, air quality, and health - An overview.

Science.gov (United States)

Wolkoff, Peder

2018-04-01

There is a long-standing dispute about indoor air humidity and perceived indoor air quality (IAQ) and associated health effects. Complaints about sensory irritation in eyes and upper airways are generally among top-two symptoms together with the perception "dry air" in office environments. This calls for an integrated analysis of indoor air humidity and eye and airway health effects. This overview has reviewed the literature about the effects of extended exposure to low humidity on perceived IAQ, sensory irritation symptoms in eyes and airways, work performance, sleep quality, virus survival, and voice disruption. Elevation of the indoor air humidity may positively impact perceived IAQ, eye symptomatology, and possibly work performance in the office environment; however, mice inhalation studies do not show exacerbation of sensory irritation in the airways by low humidity. Elevated humidified indoor air appears to reduce nasal symptoms in patients suffering from obstructive apnea syndrome, while no clear improvement on voice production has been identified, except for those with vocal fatigue. Both low and high RH, and perhaps even better absolute humidity (water vapor), favors transmission and survival of influenza virus in many studies, but the relationship between temperature, humidity, and the virus and aerosol dynamics is complex, which in the end depends on the individual virus type and its physical/chemical properties. Dry and humid air perception continues to be reported in offices and in residential areas, despite the IAQ parameter "dry air" (or "wet/humid air") is semantically misleading, because a sensory organ for humidity is non-existing in humans. This IAQ parameter appears to reflect different perceptions among other odor, dustiness, and possibly exacerbated by desiccation effect of low air humidity. It is salient to distinguish between indoor air humidity (relative or absolute) near the breathing and ocular zone and phenomena caused by moisture

Exploring the potential relationship between indoor air quality and the concentration of airborne culturable fungi: a combined experimental and neural network modeling study.

Science.gov (United States)

Liu, Zhijian; Cheng, Kewei; Li, Hao; Cao, Guoqing; Wu, Di; Shi, Yunjie

2018-02-01

Indoor airborne culturable fungi exposure has been closely linked to occupants' health. However, conventional measurement of indoor airborne fungal concentration is complicated and usually requires around one week for fungi incubation in laboratory. To provide an ultra-fast solution, here, for the first time, a knowledge-based machine learning model is developed with the inputs of indoor air quality data for estimating the concentration of indoor airborne culturable fungi. To construct a database for statistical analysis and model training, 249 data groups of air quality indicators (concentration of indoor airborne culturable fungi, indoor/outdoor PM 2.5 and PM 10 concentrations, indoor temperature, indoor relative humidity, and indoor CO 2 concentration) were measured from 85 residential buildings of Baoding (China) during the period of 2016.11.15-2017.03.15. Our results show that artificial neural network (ANN) with one hidden layer has good prediction performances, compared to a support vector machine (SVM). With the tolerance of ± 30%, the prediction accuracy of the ANN model with ten hidden nodes can at highest reach 83.33% in the testing set. Most importantly, we here provide a quick method for estimating the concentration of indoor airborne fungi that can be applied to real-time evaluation.

The possible role of indoor radon reduction systems in back-drafting residential combustion appliances

International Nuclear Information System (INIS)

Henschel, D.B.

1997-01-01

A computational sensitivity analysis was conducted to identify the conditions under which residential active soil depressurization (ASD) systems for indoor radon reduction might most likely exacerbate or create back-drafting of natural-draft combustion appliances. Parameters varied included: house size; normalized leakage area; exhaust rate of exhaust appliances other than the ASD system; and the amount of house air exhausted by the ASD system. Even with a reasonably conservative set of assumptions, it is predicted that ASD systems should not exacerbate or create back- drafting in most of the U.S. housing stock. Only at normalized leakage areas lower than 3 to 4 cm 2 commercial at 4 Pa) per m 2 of floor area should ASD contribute to back-drafting, even in small houses at high ASD exhaust rates (compared to a mean of over 10 cm 2 /m 2 determined from data on over 12,000 U.S. houses). But on the other hand, even with a more forgiving set of assumptions, it is predicted that ASD systems could contribute to back-drafting in some fraction of the housing stock -houses tighter than about 1 to 2 cm 2 /m 2 - even in large houses at minimal ASD exhaust rates. It is not possible to use parameters such as house size or ASD system flow rate to estimate reliably the risk that an ASD system might contribute to back-drafting in a given house. Spillage/back-draft testing would be needed for essentially all installations. (au) 18 refs

Risk evaluation and control strategies for indoor radon: a brief discussion

International Nuclear Information System (INIS)

Nero, A.V. Jr.

1994-01-01

Average risks of death estimated for radon are larger than those for many exposures in the outdoor environment, but similar to some in industrial settings. However, the indoor environment differs in regard to cost, benefit, responsibility, and distribution of risks from the outdoor and occupational settings, where frameworks for setting risk-limiting objectives and strategies have already been developed substantially. This indicates the need to develop a conceptual framework for evaluating risks in the indoor environment, within which the objectives of radon control strategies can be sensibly chosen. Nevertheless, the range of estimated radon risks and of recent radon control strategies suggest near-term elements of any strategy, i.e. accurate and effective public information, as well as reliable monitoring and control capabilities, and a focus on areas where most high residential levels occur. Developing a conceptual framework for evaluating indoor risks will permit the formulation of suitable aims on average indoor exposures and lower exposure situations. (author)

Indoor Thermal Comfort: The Behavioral Component

Directory of Open Access Journals (Sweden)

Jack Barkenbus

2013-04-01

Full Text Available This is a study of how indoor temperature settings have changed over time in the United States based on data from the Energy Information Administration’s, Residential Energy Consumption Survey (RECS. It is shown that Americans have moderately raised indoor temperature settings during the heating season over the past thirty years. It is also shown that most Americans keep their homes relatively cool in the summertime and are generally averse to implementing temperature setbacks. It is revealed that occupants in lower-income homes tend to set their thermostats higher in winter than other income groups, but that the most intense cooling tends to take place in both low-income and high-income homes. As expected, renters tend to heat and cool more intensively than homeowners. Getting Americans to change their temperature settings in order to save energy is not easy even though it comes with the promise of financial savings. The use of programmable thermostats thus far has proved unsuccessful. Greater utilization of social marketing to achieve energy savings is suggested, as well as a renewed effort on the part of electricity suppliers to work more closely with homeowners as part of the rollout of the “smart grid”.

Natural Ventilation Effectiveness of Round Wall-Mounted Vent Caps in Residential Kitchens

Directory of Open Access Journals (Sweden)

Yi-Pin Lin

2018-05-01

Full Text Available This study explores the effect of different numbers of wall-mounted vent caps and their installation locations on the indoor air environment in residential kitchens, for which limited information is available. Wind tunnel tests were performed to study the induced ventilation rates of a vent cap, and the impact of vent caps on the natural ventilation efficiency in residential kitchens was examined using computational fluid dynamics (CFD numerical simulations. The results were then applied to determine the appropriate quantity of vent caps and their proper installation location. The wind tunnel test results indicated that outdoor winds with speeds of 0–6 m/s that flow parallel to the wall with a vent cap induce indoor air to exit through the cap with ventilation rates of 0–20 m3/h; when the wind blows perpendicular to the wall, outdoor air with 0–31.9 m3/h flows indoors. CFD numerical simulations showed that the installation of kitchen vent caps can reduce the average carbon monoxide concentration in the cook’s breathing zone. A sufficient quantity of vent caps and the proper installation location are required to ensure the natural ventilation effectiveness of wall-mounted vent caps.

Public administration, residential weatherization, and indoor air quality: a selected bibliography. [67 references to indoor air quality

Energy Technology Data Exchange (ETDEWEB)

White, A.G.

1983-01-01

Indoor air pollution caused by weatherization materials and reduced air exchange is a new problem created by efforts to reduce energy consumption. The 67 references in this bibliography address the health effects of low-level pollutants and the legal aspects of government policies which encourage citizens to tighten their homes. (DCK)

Commuters’ Personal Exposure to Ambient and Indoor Ozone in Athens, Greece

Directory of Open Access Journals (Sweden)

Krystallia K. Kalimeri

2017-07-01

Full Text Available This pilot study aimed to monitor the residential/office indoor, outdoor, and personal levels of ozone for people living, working, and commuting in Athens, Greece. Participants (16 persons of this study worked at the same place. Passive sampling analysis results did not indicate any limit exceedance (Directive 2008/50/EC: 120 µg/m3, World Health Organization (WHO Air Quality Guidelines 2005: 100 µg/m3. The highest “house-outdoor” concentration was noticed for participants living in the north suburbs of Athens, confirming the photochemical ozone formation at the northern parts of the basin during southwestern prevailing winds. The residential indoor to outdoor ratio (I/O was found to be significantly lower than unity, underlying the outdoor originality of the pollutant. The highest “office-indoor” concentration was observed in a ground-level building, characterized by the extensive use of photocopy machines and printers. Personal ozone levels were positively correlated only with indoor-office concentrations. A clear correlation of personal ozone levels to the time spent by the individuals during moving/staying outdoors was observed. On the other hand, no correlation was observed when focusing only on commuting time, due to the fact that transit time includes both on-foot and in-vehicle time periods, therefore activities associated with increased exposure levels, but also with pollutants removal by recirculating air filtering systems, respectively.

Indoor anti-occlusion visible light positioning systems based on particle filtering

Science.gov (United States)

Jiang, Meng; Huang, Zhitong; Li, Jianfeng; Zhang, Ruqi; Ji, Yuefeng

2015-04-01

As one of the most popular categories of mobile services, a rapid growth of indoor location-based services has been witnessed over the past decades. Indoor positioning methods based on Wi-Fi, radio-frequency identification or Bluetooth are widely commercialized; however, they have disadvantages such as low accuracy or high cost. An emerging method using visible light is under research recently. The existed visible light positioning (VLP) schemes using carrier allocation, time allocation and multiple receivers all have limitations. This paper presents a novel mechanism using particle filtering in VLP system. By this method no additional devices are needed and the occlusion problem in visible light would be alleviated which will effectively enhance the flexibility for indoor positioning.

Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

Energy Technology Data Exchange (ETDEWEB)

Martin, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2014-01-01

The DOE Building America program has been conducting research leading to cost effective high performance homes since the early 1990's. Optimizing whole house mechanical ventilation as part of the program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this white paper is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

COMPARING PESTICIDE TRANSFERS FROM RESIDENTIAL SURFACE USING TRANSFERABLE RESIDUE SAMPLING TECHNIQUES AND VIDEO-FLUORESCENT IMAGING

Science.gov (United States)

The recent change from organophosphate (OP) to pyrethroid insecticides for indoor residential pest control may significantly affect the relative importance of different exposure routes because of differences in physical/chemical properties of these two classes of compounds. In...

Novel Received Signal Strength-Based Indoor Location System: Development and Testing

Directory of Open Access Journals (Sweden)

Álvarez Yuri

2010-01-01

Full Text Available A received signal strength- (RSS-based indoor location method (ILS for person/assets location in indoor scenarios is presented in this paper. Theoretical bases of the method are the integral equations relating the electromagnetic (EM fields with their sources, establishing a cost function relating the measured field at the receivers and the unknown position of the transmitter. The aim is to improve the EM characterization of the scenario yielding in a more accurate indoor location method. Regarding network infrastructure implementation, a set of receivers are deployed through the coverage area, measuring the RSS value from a transmitter node which is attached to the asset to be located. The location method is evaluated in several indoor scenarios using portable measurement equipment. The next step has been the network hardware implementation using a wireless sensor network: for this purpose, ZigBee nodes have been selected. Finally, RSS measurements variability due to multipath effects and nonline-of-sight between transmitter and receiver nodes is mitigated using calibration and a correction based on the difference between the free space field decay law and the measured RSS.

Indoor Localization with Probability Density Functionsd based on Bluetooth

OpenAIRE

Wendlandt, Kai; Robertson, Patrick; Berbig, Marcus

2005-01-01

We present a simple system to help people navigate inside of buildings or even in outside areas close to buildings. It is based on the “RSSI” and “Transmit power” data of an established Bluetooth link. The system is in principle sufficient for the intended application (pedestrian, indoor), but it is certainly not a high resolution indoor location system. The achievable accuracy is dependent on the setup (number of access points and their constellation and available Bluetooth devices) but will...

Indoor air pollutants, ventilation rate determinants and potential control strategies in Chinese dwellings: A literature review.

Science.gov (United States)

Ye, Wei; Zhang, Xu; Gao, Jun; Cao, Guangyu; Zhou, Xiang; Su, Xing

2017-05-15

After nearly twenty years of rapid modernization and urbanization in China, huge achievements have transformed the daily lives of the Chinese people. However, unprecedented environmental consequences in both indoor and outdoor environments have accompanied this progress and have triggered public awareness and demands for improved living standards, especially in residential environments. Indoor pollution data measured for >7000 dwellings (approximately 1/3 were newly decorated and were tested for volatile organic compound (VOC) measurements, while the rest were tested for particles, phthalates and other semi-volatile organic compounds (SVOCs), moisture/mold, inorganic gases and radon) in China within the last ten years were reviewed, summarized and compared with indoor concentration recommendations based on sensory or health end-points. Ubiquitous pollutants that exceed the concentration recommendations, including particulate matter, formaldehyde, benzene and other VOCs, moisture/mold, inorganic gases and radon, were found, indicating a common indoor air quality (IAQ) issue in Chinese dwellings. With very little prevention, oral, inhalation and dermal exposure to those pollutants at unhealthy concentration levels is almost inevitable. CO 2 , VOCs, humidity and radon can serve as ventilation determinants, each with different ventilation demands and strategies, at typical occupant densities in China; and particle reduction should be a prerequisite for determining ventilation requirements. Two directional ventilation modes would have profound impacts on improving IAQ for Chinese residences are: 1) natural (or window) ventilation with an air cleaner and 2) mechanical ventilation with an air filtration unit, these two modes were reviewed and compared for their applicability and advantages and disadvantages for reducing human exposure to indoor air pollutants. In general, mode 2 can more reliably ensure good IAQ for occupants; while mode 1 is more applicable due to its

A numerical study on the performance evaluation of ventilation systems for indoor radon reduction

Energy Technology Data Exchange (ETDEWEB)

Lee, Ji Eun; Park, Hoon Chae; Choi, Hang Seok; Cho, Seung Yeon; Jeong, Tae Young; Roh, Sung Cheoul [Yonsei University, Wonju (Korea, Republic of)

2016-03-15

Numerical simulations were conducted using computational fluid dynamics to evaluate the effect of ventilation conditions on radon ({sup 222}Rn) reduction performance in a residential building. The results indicate that at the same ventilation rate, a mechanical ventilation system is more effective in reducing indoor radon than a natural ventilation system. For the same ventilation type, the indoor radon concentration decreases as the ventilation rate increases. When the air change per hour (ACH) was 1, the indoor radon concentration was maintained at less than 100 Bq/m{sup 3}. However, when the ACH was lowered to 0.01, the average indoor radon concentration in several rooms exceeded 148 Bq/ m{sup 3}. The angle of the inflow air was found to affect the indoor air stream and consequently the distribution of the radon concentration. Even when the ACH was 1, the radon concentrations of some areas were higher than 100 Bq/m{sup 3} for inflow air angles of 5 .deg. and 175 .deg.

An RFID Indoor Positioning Algorithm Based on Bayesian Probability and K-Nearest Neighbor.

Science.gov (United States)

Xu, He; Ding, Ye; Li, Peng; Wang, Ruchuan; Li, Yizhu

2017-08-05

The Global Positioning System (GPS) is widely used in outdoor environmental positioning. However, GPS cannot support indoor positioning because there is no signal for positioning in an indoor environment. Nowadays, there are many situations which require indoor positioning, such as searching for a book in a library, looking for luggage in an airport, emergence navigation for fire alarms, robot location, etc. Many technologies, such as ultrasonic, sensors, Bluetooth, WiFi, magnetic field, Radio Frequency Identification (RFID), etc., are used to perform indoor positioning. Compared with other technologies, RFID used in indoor positioning is more cost and energy efficient. The Traditional RFID indoor positioning algorithm LANDMARC utilizes a Received Signal Strength (RSS) indicator to track objects. However, the RSS value is easily affected by environmental noise and other interference. In this paper, our purpose is to reduce the location fluctuation and error caused by multipath and environmental interference in LANDMARC. We propose a novel indoor positioning algorithm based on Bayesian probability and K -Nearest Neighbor (BKNN). The experimental results show that the Gaussian filter can filter some abnormal RSS values. The proposed BKNN algorithm has the smallest location error compared with the Gaussian-based algorithm, LANDMARC and an improved KNN algorithm. The average error in location estimation is about 15 cm using our method.

Indoor air pollution caused by wood-burning in Brazilian and Danish dwellings

DEFF Research Database (Denmark)

Luis Teles de Carvalho, Ricardo; Jensen, Ole Michael; da Cruz Tarelho, Luís António

2013-01-01

Residential wood-burning is considered by the scientific community as the 4th major cause of deaths in the developing countries due to the indoor air contamination and a cause of regional air pollution in the northern countries. In the first case, wood is being used by low income people that stil...

Report on the second international workshop on residential radon: Workshop proceedings

International Nuclear Information System (INIS)

1991-07-01

As a follow-on to the first International Workshop on Residential Radon Epidemiology held in Alexandria VA, on July 24-26, 1989, a Second Workshop was convened, in Alexandria, VA, July 22-23 1991, also under the auspices of the US Department of Energy and the Commission of European Communities. The Workshop, co-chaired by Jonathan Samet and Jan Stolwijk, was attended by 20 active participants from seven countries representing epidemiologic studies recently completed, currently in progress, or in the last stages of preparation. The studies reported on are being conducted in the United States, Canada, Sweden, the United Kingdom, France, Belgium, Germany and the Peoples' Republic of China. The invited presentations that initiated the Workshop focused on a number of methodological problems that have surfaced in the last few years. Among these were: (1) the difficulties in predicting indoor radon concentrations, based on geologic information, (discussed by Alan Tanner, formerly of the US Geologic Survey); (2) the relationships between indoor radon concentrations and building characteristics (discussed by Richard Sextro, Lawrence Berkeley Laboratory, USA); (3) the approaches to analysis of case-control studies in radon epidemiology (discussed by Sarah Darby, Imperial Cancer Research Fund, UK); (4) statistical approaches to error in measurements and missing data (discussed by Donna Spiegelman, Tufts University, USA); (5) preliminary results of a data pooling effort dealing with several different studies of residential radon epidemiology and the lessons to be drawn from this effort (discussed by Jay Lubin, US National Cancer Institute)

Bioaerosols in indoor environment - a review with special reference to residential and occupational locations

OpenAIRE

Mandal, J; Brandl, H

2011-01-01

Bioaerosols such as bacterial and fungal cells and their spores are - along with non-biological particles - part of indoor airborne particulate matter and have been related since a long time to health issues of human beings as well as flora, and fauna. To identify the different risks and to establish exposure thresholds, microbiology of air samples from a series of indoor environments must be characterized, i.e. the different microorganisms (bacteria and fungi) must be identified and quantifi...

Utilizing Polymer-Coated Vials to Illustrate the Fugacity and Bioavailability of Chlorinated Pesticide Residues in Contaminated Soils

Science.gov (United States)

Andrade, Natasha A.; McConnell, Laura L.; Torrents, Alba; Hapeman, Cathleen J.

2013-01-01

Fugacity and bioavailability can be used to facilitate students' understanding of potential environmental risks associated with toxic chemicals and, therefore, should be incorporated in environmental chemistry and science laboratories. Although the concept of concentration is easy to grasp, fugacity and bioavailability can be challenging…

Modeling the airborne survival of influenza virus in a residential setting: the impacts of home humidification

Science.gov (United States)

2010-01-01

Background Laboratory research studies indicate that aerosolized influenza viruses survive for longer periods at low relative humidity (RH) conditions. Further analysis has shown that absolute humidity (AH) may be an improved predictor of virus survival in the environment. Maintaining airborne moisture levels that reduce survival of the virus in the air and on surfaces could be another tool for managing public health risks of influenza. Methods A multi-zone indoor air quality model was used to evaluate the ability of portable humidifiers to control moisture content of the air and the potential related benefit of decreasing survival of influenza viruses in single-family residences. We modeled indoor AH and influenza virus concentrations during winter months (Northeast US) using the CONTAM multi-zone indoor air quality model. A two-story residential template was used under two different ventilation conditions - forced hot air and radiant heating. Humidity was evaluated on a room-specific and whole house basis. Estimates of emission rates for influenza virus were particle-size specific and derived from published studies and included emissions during both tidal breathing and coughing events. The survival of the influenza virus was determined based on the established relationship between AH and virus survival. Results The presence of a portable humidifier with an output of 0.16 kg water per hour in the bedroom resulted in an increase in median sleeping hours AH/RH levels of 11 to 19% compared to periods without a humidifier present. The associated percent decrease in influenza virus survival was 17.5 - 31.6%. Distribution of water vapor through a residence was estimated to yield 3 to 12% increases in AH/RH and 7.8-13.9% reductions in influenza virus survival. Conclusion This modeling analysis demonstrates the potential benefit of portable residential humidifiers in reducing the survival of aerosolized influenza virus by controlling humidity indoors. PMID:20815876

Modeling the airborne survival of influenza virus in a residential setting: the impacts of home humidification

Directory of Open Access Journals (Sweden)

Myatt Theodore A

2010-09-01

Full Text Available Abstract Background Laboratory research studies indicate that aerosolized influenza viruses survive for longer periods at low relative humidity (RH conditions. Further analysis has shown that absolute humidity (AH may be an improved predictor of virus survival in the environment. Maintaining airborne moisture levels that reduce survival of the virus in the air and on surfaces could be another tool for managing public health risks of influenza. Methods A multi-zone indoor air quality model was used to evaluate the ability of portable humidifiers to control moisture content of the air and the potential related benefit of decreasing survival of influenza viruses in single-family residences. We modeled indoor AH and influenza virus concentrations during winter months (Northeast US using the CONTAM multi-zone indoor air quality model. A two-story residential template was used under two different ventilation conditions - forced hot air and radiant heating. Humidity was evaluated on a room-specific and whole house basis. Estimates of emission rates for influenza virus were particle-size specific and derived from published studies and included emissions during both tidal breathing and coughing events. The survival of the influenza virus was determined based on the established relationship between AH and virus survival. Results The presence of a portable humidifier with an output of 0.16 kg water per hour in the bedroom resulted in an increase in median sleeping hours AH/RH levels of 11 to 19% compared to periods without a humidifier present. The associated percent decrease in influenza virus survival was 17.5 - 31.6%. Distribution of water vapor through a residence was estimated to yield 3 to 12% increases in AH/RH and 7.8-13.9% reductions in influenza virus survival. Conclusion This modeling analysis demonstrates the potential benefit of portable residential humidifiers in reducing the survival of aerosolized influenza virus by controlling humidity

Occurrence, dynamics and reactions of organic pollutants in the indoor environment

Energy Technology Data Exchange (ETDEWEB)

Salthammer, Tunga [Material Analysis and Indoor Chemistry, Fraunhofer Wilhelm-Klauditz Institut (WKI), Braunschweig (Germany); Bahadir, Muefit [Institut fuer Oekologische Chemie und Abfallanalytik, Technische Universitaet Braunschweig, Braunschweig (Germany)

2009-06-15

The indoor environment is a multidisciplinary scientific field involving chemistry, physics, biology, health sciences, architecture, building sciences and civil engineering. The need for reliable assessment of human exposure to indoor pollutants is attracting increasing attention. This, however, requires a detailed understanding of the relevant compounds, their sources, physical and chemical properties, dynamics, reactions, their distribution among the gas phase, airborne particles and settled dust as well as the availability of modern measurement techniques. Building products, furnishings and other indoor materials often emit volatile and semi-volatile organic compounds. With respect to a healthy indoor environment, only low emitting products, which do not influence indoor air quality in a negative way, should be used in a building. Therefore, materials and products for indoor use need to be evaluated for their chemical emissions. This is routinely done in test chambers and cells. Many studies have shown that the types of sources in occupational and residential indoor environments, the spectrum of emitting compounds and the duration of emission cover a wide range. The demand for standardized test methods under laboratory conditions has resulted in several guidelines for determination of emission rates. Furthermore, it has now been recognized that both primary and secondary emissions may affect indoor air quality. The problem may become more dominant when components of different materials can react with each other or when catalytic materials are applied. Such products derived from indoor related reactions may have a negative impact on indoor air quality due to their low odor threshold, health related properties or the formation of ultrafine particles. Several factors can influence the emission characteristics and numerous investigations have shown that indoor chemistry is of particular importance for the indoor related characterization of building product emissions

Three-dimensional reconstruction of indoor whole elements based on mobile LiDAR point cloud data

Science.gov (United States)

Gong, Yuejian; Mao, Wenbo; Bi, Jiantao; Ji, Wei; He, Zhanjun

2014-11-01

Ground-based LiDAR is one of the most effective city modeling tools at present, which has been widely used for three-dimensional reconstruction of outdoor objects. However, as for indoor objects, there are some technical bottlenecks due to lack of GPS signal. In this paper, based on the high-precision indoor point cloud data which was obtained by LiDAR, an international advanced indoor mobile measuring equipment, high -precision model was fulfilled for all indoor ancillary facilities. The point cloud data we employed also contain color feature, which is extracted by fusion with CCD images. Thus, it has both space geometric feature and spectral information which can be used for constructing objects' surface and restoring color and texture of the geometric model. Based on Autodesk CAD platform and with help of PointSence plug, three-dimensional reconstruction of indoor whole elements was realized. Specifically, Pointools Edit Pro was adopted to edit the point cloud, then different types of indoor point cloud data was processed, including data format conversion, outline extracting and texture mapping of the point cloud model. Finally, three-dimensional visualization of the real-world indoor was completed. Experiment results showed that high-precision 3D point cloud data obtained by indoor mobile measuring equipment can be used for indoor whole elements' 3-d reconstruction and that methods proposed in this paper can efficiently realize the 3 -d construction of indoor whole elements. Moreover, the modeling precision could be controlled within 5 cm, which was proved to be a satisfactory result.

Cellular Automata-Based Application for Driver Assistance in Indoor Parking Areas

Directory of Open Access Journals (Sweden)

Cándido Caballero-Gil

2016-11-01

Full Text Available This work proposes an adaptive recommendation mechanism for smart parking that takes advantage of the popularity of smartphones and the rise of the Internet of Things. The proposal includes a centralized system to forecast available indoor parking spaces, and a low-cost mobile application to obtain data of actual and predicted parking occupancy. The described scheme uses data from both sources bidirectionally so that the centralized forecast system is fed with data obtained with the distributed system based on smartphones, and vice versa. The mobile application uses different wireless technologies to provide the forecast system with actual parking data and receive from the system useful recommendations about where to park. Thus, the proposal can be used by any driver to easily find available parking spaces in indoor facilities. The client software developed for smartphones is a lightweight Android application that supplies precise indoor positioning systems based on Quick Response codes or Near Field Communication tags, and semi-precise indoor positioning systems based on Bluetooth Low Energy beacons. The performance of the proposed approach has been evaluated by conducting computer simulations and real experimentation with a preliminary implementation. The results have shown the strengths of the proposal in the reduction of the time and energy costs to find available parking spaces.

Cellular Automata-Based Application for Driver Assistance in Indoor Parking Areas.

Science.gov (United States)

Caballero-Gil, Cándido; Caballero-Gil, Pino; Molina-Gil, Jezabel

2016-11-15

This work proposes an adaptive recommendation mechanism for smart parking that takes advantage of the popularity of smartphones and the rise of the Internet of Things. The proposal includes a centralized system to forecast available indoor parking spaces, and a low-cost mobile application to obtain data of actual and predicted parking occupancy. The described scheme uses data from both sources bidirectionally so that the centralized forecast system is fed with data obtained with the distributed system based on smartphones, and vice versa. The mobile application uses different wireless technologies to provide the forecast system with actual parking data and receive from the system useful recommendations about where to park. Thus, the proposal can be used by any driver to easily find available parking spaces in indoor facilities. The client software developed for smartphones is a lightweight Android application that supplies precise indoor positioning systems based on Quick Response codes or Near Field Communication tags, and semi-precise indoor positioning systems based on Bluetooth Low Energy beacons. The performance of the proposed approach has been evaluated by conducting computer simulations and real experimentation with a preliminary implementation. The results have shown the strengths of the proposal in the reduction of the time and energy costs to find available parking spaces.

An RFID Indoor Positioning Algorithm Based on Bayesian Probability and K-Nearest Neighbor

Directory of Open Access Journals (Sweden)

He Xu

2017-08-01

Full Text Available The Global Positioning System (GPS is widely used in outdoor environmental positioning. However, GPS cannot support indoor positioning because there is no signal for positioning in an indoor environment. Nowadays, there are many situations which require indoor positioning, such as searching for a book in a library, looking for luggage in an airport, emergence navigation for fire alarms, robot location, etc. Many technologies, such as ultrasonic, sensors, Bluetooth, WiFi, magnetic field, Radio Frequency Identification (RFID, etc., are used to perform indoor positioning. Compared with other technologies, RFID used in indoor positioning is more cost and energy efficient. The Traditional RFID indoor positioning algorithm LANDMARC utilizes a Received Signal Strength (RSS indicator to track objects. However, the RSS value is easily affected by environmental noise and other interference. In this paper, our purpose is to reduce the location fluctuation and error caused by multipath and environmental interference in LANDMARC. We propose a novel indoor positioning algorithm based on Bayesian probability and K-Nearest Neighbor (BKNN. The experimental results show that the Gaussian filter can filter some abnormal RSS values. The proposed BKNN algorithm has the smallest location error compared with the Gaussian-based algorithm, LANDMARC and an improved KNN algorithm. The average error in location estimation is about 15 cm using our method.

Integrated Management of Residential Indoor Air Quality: A Call for Stakeholders in a Changing Climate.

Science.gov (United States)

Levasseur, Marie-Eve; Poulin, Patrick; Campagna, Céline; Leclerc, Jean-Marc

2017-11-25

A paradigm change in the management of environmental health issues has been observed in recent years: instead of managing specific risks individually, a holistic vision of environmental problems would assure sustainable solutions. However, concrete actions that could help translate these recommendations into interventions are lacking. This review presents the relevance of using an integrated indoor air quality management approach to ensure occupant health and comfort. At the nexus of three basic concepts (reducing contaminants at the source, improving ventilation, and, when relevant, purifying the indoor air), this approach can help maintain and improve indoor air quality and limit exposure to several contaminants. Its application is particularly relevant in a climate change context since the evolving outdoor conditions have to be taken into account during building construction and renovation. The measures presented through this approach target public health players, building managers, owners, occupants, and professionals involved in building design, construction, renovation, and maintenance. The findings of this review will help the various stakeholders initiate a strategic reflection on the importance of indoor air quality and climate change issues for existing and future buildings. Several new avenues and recommendations are presented to set the path for future research activities.

Risk of Lung Cancer and Indoor Radon Exposure in France

International Nuclear Information System (INIS)

Baysson, H.; Tirmarche, M.; Tymen, G.; Ducloy, F.; Laurier, D.

2004-01-01

It is well established that radon exposure increases risks of lung cancer among underground miners. to estimate the lung cancer risk linked to indoor radon exposure, a hospital based case-control study was carried out in France, With a focus on precise reconstruction of past indoor radon exposure over the 30 years preceding the lung cancer diagnosis. The investigation rook place from 1992 to 1998 in four regions of France: Auvergne, Brittany, Languedoc and Limousin. During face-to-face interviews a standardized questionnaire was used to ascertain demographic characteristics, information on active and passive smoking, occupational exposure, medical history as well as extensive details on residential history. Radon concentrations were measured in the dwellings where subjects had lived at least one year during the 5-30 year period before interview. Measurements of radon concentrations were performed during a 6-month period, using two Kodalpha LR 115 detectors, one in the living room and one in the bedroom. The time-weighted average (TWA) radon concentration for a subject during the 5-30 year period before interview was based on radon concentrations over all addresses occupied by the subject weighted by the number of years spent at each address. For the time intervals without available measurements, we imputed the region-specific arithmetic average of radon concentrations for measured addresses of control subjects. Lung cancer risk was examined in relation to indoor radon exposure after adjustment for age, sex, region, cigarette smoking and occupational exposure. The estimated relative a risk per 100 Bq/m''3 was 1.04, at the borderline of statistical significance (95 percent Confidence Interval: 0.99, 1..1). These results are in agreement with results from other indoor radon case-control studies and with extrapolations from underground miners studies. (Author) 31 refs

Hybrid Indoor-Based WLAN-WSN Localization Scheme for Improving Accuracy Based on Artificial Neural Network

Directory of Open Access Journals (Sweden)

Zahid Farid

2016-01-01

Full Text Available In indoor environments, WiFi (RSS based localization is sensitive to various indoor fading effects and noise during transmission, which are the main causes of localization errors that affect its accuracy. Keeping in view those fading effects, positioning systems based on a single technology are ineffective in performing accurate localization. For this reason, the trend is toward the use of hybrid positioning systems (combination of two or more wireless technologies in indoor/outdoor localization scenarios for getting better position accuracy. This paper presents a hybrid technique to implement indoor localization that adopts fingerprinting approaches in both WiFi and Wireless Sensor Networks (WSNs. This model exploits machine learning, in particular Artificial Natural Network (ANN techniques, for position calculation. The experimental results show that the proposed hybrid system improved the accuracy, reducing the average distance error to 1.05 m by using ANN. Applying Genetic Algorithm (GA based optimization technique did not incur any further improvement to the accuracy. Compared to the performance of GA optimization, the nonoptimized ANN performed better in terms of accuracy, precision, stability, and computational time. The above results show that the proposed hybrid technique is promising for achieving better accuracy in real-world positioning applications.

Indoor air quality in a multifamily apartment building before and after energy renovation

DEFF Research Database (Denmark)

Bekö, Gabriel; Földváry, Veronika; Langer, Sarka

2016-01-01

Buildings are responsible for a substantial portion of global energy consumption. Most of the multifamily residential buildings in central Europe built in the 20th century do not satisfy the current requirements on energy efficiency. Nationwide remedial measures are taken to improve the energy ef...... exchange rates and acceptable and healthy IAQ. Without these considerations, energy reconstruction can adversely affect the quality of the indoor environment....... efficiency of these buildings and reduce their energy consumption. Since the impact of these measures on the indoor air quality is rarely considered, they often compromise indoor air quality due to decreased ventilation and infiltration rate. We compared the indoor air quality in a multifamily apartment...... building in Slovakia before and after energy renovation, during two subsequent winters. Measurements of temperature, relative humidity, concentrations of CO2, formaldehyde, NO2, and volatile organic compounds were performed during one week in January 2015 in 20 apartments in one multifamily building...

The distribution of indoor radon in Transylvania (Romania) - influence of the natural and anthropogenic factors

Science.gov (United States)

Cucos Dinu, Alexandra; Baciu, Calin; Dicu, Tiberius; Papp, Botond; Moldovan, Mircea; Bety Burghele, Denissa; Tenter, Ancuta; Szacsvai, Kinga

2017-04-01

Exposure to radon in homes and workplaces is now recognized as the most important natural factor in causing lung cancer. Radon activity is usually higher in buildings than in the outside atmosphere, as it may be released from building materials and soil beneath the constructions, and the concentration builds-up indoor, due to the low air renewal rates. Indoor radon levels can vary from one to multiple orders of magnitude over time and space, as it depends on several natural and anthropogenic factors, such us the radon concentration in soil under the construction, the weather conditions, the degree of containment in the areas where individuals are exposed, building materials, outside air, tap water and even city gas, the architecture, equipment (chimney, mechanical ventilation systems, etc.), the environmental parameters of the building (temperature, pressure, etc.), and on the occupants' lifestyle. The study presents the distribution of indoor radon in Transylvania, Romania, together with the measurements of radon in soil and soil water. Indoor radon measurements were performed by using CR-39 track detectors exposed for 3 months on ground-floor level of dwellings, according to the NRPB Measurement Protocol. Radon concentrations in soil and water were measured using the LUK3C device. A complete map was plotted at the date, based on 3300 indoor radon measurements, covering an area of about 42% of the Romanian territory. The indoor radon concentrations ranged from 5 to 3287 Bq m-3, with an updated preliminary arithmetic mean of 179 Bq m-3, and a geometric mean of 122 Bq m-3. In about 11% of the investigated grid cells the indoor radon concentrations exceed the threshold of 300 Bq m-3. The soil gas radon concentration varies from 0.8 to 169 kBq m-3, with a geometric mean of 26 kBq m-3. For water samples, the results show radon concentrations within the range of 0.3 - 352.2 kBq m-3, with a geometric mean of 7.7 Bq L-1. A weak correlation between the three sets of values

Applying water cooled air conditioners in residential buildings in Hong Kong

International Nuclear Information System (INIS)

Chen Hua; Lee, W.L.; Yik, F.W.H.

2008-01-01

The objective of this study is to conduct a realistic prediction of the potential energy saving for using water cooled air conditioners in residential buildings in Hong Kong. A split type air conditioner with air cooled (AAC) and water cooled (WAC) options was set up for experimental study at different indoor and outdoor conditions. The cooling output, power consumption and coefficient of performance (COP) of the two options were measured and calculated for comparison. The experimental results showed that the COP of the WAC is, on average, 17.4% higher than that of the AAC. The results were used to validate the mathematical models formulated for predicting the performance of WACs and AACs at different operating conditions and load characteristics. While the development of the mathematical models for WACs was reported in an earlier paper, this paper focuses on the experimental works for the AAC. The mathematical models were further used to predict the potential energy saving for application of WACs in residential buildings in Hong Kong. The predictions were based on actual building developments and realistic operating characteristics. The overall energy savings were estimated to be around 8.7% of the total electricity consumption for residential buildings in Hong Kong. Wider use of WACs in subtropical cities is, therefore, recommended

Application of Wireless Sensor Networks for Indoor Temperature Regulation

DEFF Research Database (Denmark)

Stojkoska, Biljana Risteska; Popovska Avramova, Andrijana; Chatzimisios, Periklis

2014-01-01

Wireless sensor networks take a major part in our everyday lives by enhancing systems for home automation, healthcare, temperature control, energy consumption monitoring, and so forth. In this paper we focus on a system used for temperature regulation for residential, educational, industrial...... energy savings by reducing the amount of data transmissions through the network. Furthermore, the framework explores techniques for localization, such that the location of the nodes can be used by algorithms that regulate temperature settings......., and commercial premises, and so forth. We propose a framework for indoor temperature regulation and optimization using wireless sensor networks based on ZigBee platform. This paper considers architectural design of the system, as well as implementation guidelines. The proposed system favors methods that provide...

Relative Panoramic Camera Position Estimation for Image-Based Virtual Reality Networks in Indoor Environments

Science.gov (United States)

Nakagawa, M.; Akano, K.; Kobayashi, T.; Sekiguchi, Y.

2017-09-01

Image-based virtual reality (VR) is a virtual space generated with panoramic images projected onto a primitive model. In imagebased VR, realistic VR scenes can be generated with lower rendering cost, and network data can be described as relationships among VR scenes. The camera network data are generated manually or by an automated procedure using camera position and rotation data. When panoramic images are acquired in indoor environments, network data should be generated without Global Navigation Satellite Systems (GNSS) positioning data. Thus, we focused on image-based VR generation using a panoramic camera in indoor environments. We propose a methodology to automate network data generation using panoramic images for an image-based VR space. We verified and evaluated our methodology through five experiments in indoor environments, including a corridor, elevator hall, room, and stairs. We confirmed that our methodology can automatically reconstruct network data using panoramic images for image-based VR in indoor environments without GNSS position data.

RELATIVE PANORAMIC CAMERA POSITION ESTIMATION FOR IMAGE-BASED VIRTUAL REALITY NETWORKS IN INDOOR ENVIRONMENTS

Directory of Open Access Journals (Sweden)

M. Nakagawa

2017-09-01

Full Text Available Image-based virtual reality (VR is a virtual space generated with panoramic images projected onto a primitive model. In imagebased VR, realistic VR scenes can be generated with lower rendering cost, and network data can be described as relationships among VR scenes. The camera network data are generated manually or by an automated procedure using camera position and rotation data. When panoramic images are acquired in indoor environments, network data should be generated without Global Navigation Satellite Systems (GNSS positioning data. Thus, we focused on image-based VR generation using a panoramic camera in indoor environments. We propose a methodology to automate network data generation using panoramic images for an image-based VR space. We verified and evaluated our methodology through five experiments in indoor environments, including a corridor, elevator hall, room, and stairs. We confirmed that our methodology can automatically reconstruct network data using panoramic images for image-based VR in indoor environments without GNSS position data.

Exposure to Indoor Allergens in Different Residential Settings and Its Influence on IgE Sensitization in a Geographically Confined Austrian Cohort.

Directory of Open Access Journals (Sweden)

Teresa Stemeseder

Full Text Available Exposure to indoor allergens is crucial for IgE sensitization and development of allergic symptoms. Residential settings influence the allergen amount in house dust and hence allergic sensitization. Within this study, we investigated allergen exposure and molecule-based IgE levels in a geographically confined region and evaluated the impact of housing, pets and cleaning.501 adolescents from Salzburg, Austria participated in this cross-sectional study. House dust samples were examined regarding major mite, cat, dog, and mold allergens using a multiplex assay. Serum samples of participants were analyzed for specific IgE to Der p 1, Der p 2, Fel d 1, Can f 1 and Alt a 1 using the multiplex array ImmunoCAP ISAC. Information on allergies, living areas, dwelling form (house, flat, farm, pets, and household cleanliness were obtained by a questionnaire.In investigated house dust samples, the concentration of cat allergen was highest while the prevalence of mold allergens was very low. Participants showed IgE sensitization to Der p 1 (13.2%, Der p 2 (18.2%, Fel d 1 (14.4%, Can f 1 (2.4% and Alt a 1 (2.0%. In alpine regions, lower mite allergen concentrations were detected which correlated with reduced IgE levels. A trend for increased sensitization prevalence from rural to alpine to urban regions was noted. Living on farms resulted in lower sensitization prevalence to mite and cat allergens, even though exposure to mites was significantly elevated. The presence of cats was associated with a lower sensitization rate and IgE levels to cat and mite allergens, and less frequent allergic diseases. Cleaning did not impact allergen concentrations, while IgE reactivity to mites and allergic diseases were more pronounced when living in cleaner homes.Allergen exposure to indoor allergens was influenced by setting of homes. Living in a farm environment and having a cat at home showed a protective effect for IgE sensitization and allergies. This cross

Testing a social cognitive theory-based model of indoor tanning: implications for skin cancer prevention messages.

Science.gov (United States)

Noar, Seth M; Myrick, Jessica Gall; Zeitany, Alexandra; Kelley, Dannielle; Morales-Pico, Brenda; Thomas, Nancy E

2015-01-01

The lack of a theory-based understanding of indoor tanning is a major impediment to the development of effective messages to prevent or reduce this behavior. This study applied the Comprehensive Indoor Tanning Expectations (CITE) scale in an analysis of indoor tanning behavior among sorority women (total N = 775). Confirmatory factor analyses indicated that CITE positive and negative expectations were robust, multidimensional factors and that a hierarchical structure fit the data well. Social cognitive theory-based structural equation models demonstrated that appearance-oriented variables were significantly associated with outcome expectations. Outcome expectations were, in turn, significantly associated with temptations to tan, intention to tan indoors, and indoor tanning behavior. The implications of these findings for the development of messages to prevent and reduce indoor tanning behavior are discussed in two domains: (a) messages that attempt to change broader societal perceptions about tan skin, and (b) messages that focus more narrowly on indoor tanning-challenging positive expectations, enhancing negative expectations, and encouraging substitution of sunless tanning products.

Parametric studies and evaluations of indoor thermal environment in wet season using a field survey and PMV-PPD method

Energy Technology Data Exchange (ETDEWEB)

Wei, Shengxian [College of Physics and Electric Engineering, Qujing Normal University, Qujing 655011 (China); Key Laboratory of Advanced Technique and Preparation for Renewable Energy Materials, Ministry of Education, Yunnan Normal University, Kunming 650092 (China); Li, Ming [Key Laboratory of Advanced Technique and Preparation for Renewable Energy Materials, Ministry of Education, Yunnan Normal University, Kunming 650092 (China); Lin, Wenxian [Key Laboratory of Advanced Technique and Preparation for Renewable Energy Materials, Ministry of Education, Yunnan Normal University, Kunming 650092 (China); School of Engineering, James Cook University, Townsville, QLD 4811 (Australia); Sun, Yanlin [College of Physics and Electric Engineering, Qujing Normal University, Qujing 655011 (China)

2010-06-15

Fanger's PMV-PPD is the most famous thermal sensation indices but it is too complex to be applied in practice. To obtain simple and applicable correlations, taking Qujing of Yunnan province, China, as example, a wet season (six-month) field measurement was conducted in a naturally ventilated residential room. Based on collected data, PMV indices were calculated by using Newton's iterative method. It is shown that the PMV values approximately vary from -1.0 to +1.0 and the indoor thermal environment is basically comfortable. Relationships of the parameters (indoor and outdoor air temperatures, mean radiant temperature, PMV and PPD) and indoor air temperature gradients (vertical and horizontal) were also studied by means of the linear regression and the quadratic polynomial fit techniques. Numerous correlations with high relativities have been developed. Moreover, the vertical and horizontal air temperature gradients range from 0.1 K/m to 0.85 K/m and from -0.208 K/m to 0.063 K/m in wet season. It is convenient to use these results to evaluate and assess the indoor thermal environment under similar climatic conditions. The results of this work enrich and develop the basic theory of the indoor thermal environment design and control. (author)

Secure positioning technique based on encrypted visible light map for smart indoor service

Science.gov (United States)

Lee, Yong Up; Jung, Gillyoung

2018-03-01

Indoor visible light (VL) positioning systems for smart indoor services are negatively affected by both cochannel interference from adjacent light sources and VL reception position irregularity in the three-dimensional (3-D) VL channel. A secure positioning methodology based on a two-dimensional (2-D) encrypted VL map is proposed, implemented in prototypes of the specific positioning system, and analyzed based on performance tests. The proposed positioning technique enhances the positioning performance by more than 21.7% compared to the conventional method in real VL positioning tests. Further, the pseudonoise code is found to be the optimal encryption key for secure VL positioning for this smart indoor service.

The effect of oxygen fugacity on the rheological evolution of crystallizing basaltic melts

Science.gov (United States)

Kolzenburg, S.; Di Genova, D.; Giordano, D.; Hess, K. U.; Dingwell, D. B.

2018-04-01

Storage and transport of silicate melts in the Earth's crust and their emplacement on the planet's surface occur almost exclusively at sub-liquidus temperatures. At these conditions, the melts undergo crystallization under a wide range of cooling-rates, deformation-rates, and oxygen fugacities (fO2). Oxygen fugacity is known to influence the thermodynamics and kinetics of crystallization in magmas and lavas. Yet, its influence on sub-liquidus rheology remains largely uncharted. We present the first rheological characterization of crystallizing lavas along natural cooling paths and deformation-rates and at varying fO2. Specifically, we report on apparent viscosity measurements for two crystallizing magmatic suspensions 1) at log ⁡ fO2 of -9.15 (quartz-fayalite-magnetite buffer, QFM, -2.1) and 2) in air. These fugacities span a range of reduced to oxidized conditions pertinent to magma migration and lava emplacement. We find that: 1) crystallization at constant cooling-rates results in a quasi-exponential increase in the apparent viscosity of the magmatic suspensions until they achieve their rheological cut off temperature (Tcutoff), where the melt effectively solidifies 2) the rheological departure and Tcutoff increase with increasing fO2 and 3) increasing fO2 results in decreased crystallization-rates. Based on the experimental results and by comparison with previous rheological isothermal studies we propose a generalisation of the effect of fO2 on the dynamic rheological evolution of natural magmatic and volcanic suspensions. We further discuss the implications for magmatic transport in plumbing and storage systems (e.g. conduits, dikes and magma chambers) and during lava flow emplacement.

Preliminary assessment of BTEX concentrations in indoor air of residential buildings and atmospheric ambient air in Ardabil, Iran

Science.gov (United States)

Hazrati, Sadegh; Rostami, Roohollah; Farjaminezhad, Manoochehr; Fazlzadeh, Mehdi

2016-05-01

BTEX concentrations in indoor and outdoor air of 50 homes were studied in Ardabil city and their influencing parameters including; heating system, using gas stove and samovar, tobacco smoking, the floors in which the monitored homes were located, and kitchen plan were considered in the study. Risk assessment analysis was carried out with the obtained concentrations based on EPA IRIS reference doses. BTEX compounds were sampled by charcoal tubes and the samples were analyzed by a GC-FID. Concentrations of benzene (15.18 μg/m3 vs. 8.65 μg/m3), toluene (69.70 μg/m3 vs. 40.56 μg/m3), ethylbenzene (12.07 μg/m3 vs. 4.92 μg/m3) and xylene (48.08 μg/m3 vs. 7.44 μg/m3) in indoor air were significantly (p < 0.05) higher than the levels quantified for outdoor air. The obtained concentrations of benzene were considerably higher than the recommended value of 5 μg/m3 established by Iran environmental protection organization. Among the BTEX compounds, benzene (HQ = 0.51) and xylene (HQ = 0.47) had notable hazard quotient and were the main pollutants responsible for high hazard index in the monitored homes (HI = 1.003). The results showed considerably high cancer risk for lifetime exposure to the indoor (125 × 10-6) and outdoor (71 × 10-6) benzene. Indoor benzene concentrations in homes were significantly influenced by type of heating system, story, and natural gas appliances.

Health behaviours associated with indoor tanning based on the 2012/13 Manitoba Youth Health Survey

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E. Harland

2016-08-01

Full Text Available Introduction: Although indoor tanning causes cancer, it remains relatively common among adolescents. Little is known about indoor tanning prevalence and habits in Canada, and even less about associated behaviours. This study explores the prevalence of adolescent indoor tanning in Manitoba and its association with other demographic characteristics and health behaviours. Methods: We conducted secondary analyses of the 2012/13 Manitoba Youth Health Survey data collected from Grade 7 to 12 students (n = 64 174 and examined associations between indoor tanning (whether participants had ever used artificial tanning equipment and 25 variables. Variables with statistically significant associations to indoor tanning were tested for collinearity and grouped based on strong associations. For each group of highly associated variables, the variable with the greatest effect upon indoor tanning was placed into the final logistic regression model. Separate analyses were conducted for males and females to better understand sex-based differences, and analyses were adjusted for age. Results: Overall, 4% of male and 9% of female students reported indoor tanning, and prevalence increased with age. Relationships between indoor tanning and other variables were similar for male and female students. Binary logistic regression models indicated that several variables significantly predicted indoor tanning, including having part-time work, being physically active, engaging in various risk behaviours such as driving after drinking for males and unplanned sex after alcohol/drugs for females, experiencing someone say something bad about one's body shape/size/appearance, identifying as trans or with another gender, consuming creatine/other supplements and, for females only, never/rarely using sun protection. Conclusion: Indoor tanning among adolescents was associated with age, part-time work, physical activity and many consumption behaviours and lifestyle risk factors. Though

The contribution of indoor pollution to the contamination level on a regional basis (Greater Rhone Delta Program)

International Nuclear Information System (INIS)

Aigueperse, J.; Anguenot, F.; Person, A.; Laurent, A.M.; Louis-Gavet, M.C.; Festy, B.

1989-01-01

People of industrialized countries spend at most 22 hours per day indoor (at home, at work, in transit, ...) and specifically about 14 hours In residential indoor environments. So, indoor air quality cannot be ignored when evaluating the impact of all quality on human health; indeed, householders were encouraged to insulate homes and to seal up public buildings. At the same time, technological developments give rise to many new synthetic products which contain organic chemicals, like building materials, home decoration materials and consumer home products . Only, these later two classes have been studied. Firstly, inventory and annual consumption of consumer home products sold in France have been carried out to realize a French data base concerning volatile organic compound (VOCs) emissions of consumer home products. Secondly, methods to measure the emissions of VOCs were developed. They concern 4 types of consumer products in three conditioning forms: aerosol bombs, solids, pastes. 4 body deodorants, 3 hairsprays, 2 toilet bowl deodorizers and 11 glues were analyzed for the presence of several VOCs. Qualitative and quantitative data were obtained. (author)

Analysis of the systems of ventilation of residential houses of Ukraine and Estonia

Science.gov (United States)

Savchenko, Olena; Zhelykh, Vasyl; Voll, Hendrik

2017-12-01

The most common ventilation system in residential buildings in Ukraine is natural ventilation. In recent years, due to increased tightness of structures, an increase in the content of synthetic finishing materials in them, the quality of microclimate parameters deteriorated. One of the measures to improve the parameters of indoor air in residential buildings is the use of mechanical inflow and exhaust ventilation system. In this article the regulatory documents concerning the design of ventilation systems in Ukraine and Estonia and the requirements for air exchange in residential buildings are considered. It is established that the existing normative documents in Ukraine are analogous to European norms, which allow design the system of ventilation of residential buildings according to European standards. However, the basis for the design of ventilation systems in Ukraine is the national standards, in which mechanical ventilation, unfortunately, is provided only for the design of high-rise buildings. To maintain acceptable microclimate parameters in residential buildings, it is advisable for designers to apply the requirements for designing ventilation systems in accordance with European standards.

Analysis of the systems of ventilation of residential houses of Ukraine and Estonia

Directory of Open Access Journals (Sweden)

Savchenko Olena

2017-12-01

Full Text Available The most common ventilation system in residential buildings in Ukraine is natural ventilation. In recent years, due to increased tightness of structures, an increase in the content of synthetic finishing materials in them, the quality of microclimate parameters deteriorated. One of the measures to improve the parameters of indoor air in residential buildings is the use of mechanical inflow and exhaust ventilation system. In this article the regulatory documents concerning the design of ventilation systems in Ukraine and Estonia and the requirements for air exchange in residential buildings are considered. It is established that the existing normative documents in Ukraine are analogous to European norms, which allow design the system of ventilation of residential buildings according to European standards. However, the basis for the design of ventilation systems in Ukraine is the national standards, in which mechanical ventilation, unfortunately, is provided only for the design of high-rise buildings. To maintain acceptable microclimate parameters in residential buildings, it is advisable for designers to apply the requirements for designing ventilation systems in accordance with European standards.

Design of environmentally friendly calcium sulfate-based building materials : towards an improved indoor air quality

NARCIS (Netherlands)

Yu, Q.

2012-01-01

This thesis addresses the performance based design and development of an environmentally friendly calcium sulfate-based indoor building product towards an improved indoor air quality. Here "environmental friendly" is referred to the environment related subjects including: (1) the selection of raw

A Participatory Agent-Based Simulation for Indoor Evacuation Supported by Google Glass

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Jesús M. Sánchez

2016-08-01

Full Text Available Indoor evacuation systems are needed for rescue and safety management. One of the challenges is to provide users with personalized evacuation routes in real time. To this end, this project aims at exploring the possibilities of Google Glass technology for participatory multiagent indoor evacuation simulations. Participatory multiagent simulation combines scenario-guided agents and humans equipped with Google Glass that coexist in a shared virtual space and jointly perform simulations. The paper proposes an architecture for participatory multiagent simulation in order to combine devices (Google Glass and/or smartphones with an agent-based social simulator and indoor tracking services.

Concentrations of indoor radon and thoron in cave-dwellings with discussions on risk estimation of lung cancer

International Nuclear Information System (INIS)

Sun Quanfu; Hou Changsong; Zhang Shouzhi; Nie Xiaoqian; Shang Bing

2005-01-01

Objective: To explore a residential area with elevated indoor radon exposure for conducting epidemiological studies on indoor radon and lung cancer. Methods: Two hundred and two cave-dwellings (CD) including loess CD, brick CD, stone CD, and ordinary house in twenty villages were selected from Yan'an and Lvliang in the Chinese loess plateau. Indoor levels of thoron and its progeny as well as radon were measured with passive radon-thoron discriminative detectors and thoron progeny deposition rate devices. The exposure period covered from August 2001 through August 2002. Results: Loess CD was one of the most common type of dwelling caves in both areas. The indoor radon concentrations in loess CD ranged from 17 to 179 Bq/m 3 ; thoron varied sub-stantially depending upon the distance from the device to the wall, ranged from 10 to 760 Bq/m 3 . Geometric means of indoor radon, thoron and thoron's progeny (EEC Tn ) of loess caves in Yan'an area were estimated to be 71, 185 and 2.2 Bq/m 3 , respectively, and the corresponding figures were 73, 145 and 116 Bq/m 3 in Lvliang area. Possible contamination of thoron on radon measurement in a previous case-control study on lung caner was discussed. The study revealed that the indoor air pollution in Yan'an area was slight compared with that in Lvliang area. Migration was very low. Eighty-six percent of the investigated persons have had no migration in Yan'an area, and 90 percent of the cave-dwellings where the subjects once resided were available to our measurements. Two million people have been living in cave-dwellings over several generations. Conclusion: The investigated cave-dwelling area in Yan'an is suitable for conducting epidemiological study on residential thoron and radon exposure and lung cancer.(authors)

Cellular Automata-Based Application for Driver Assistance in Indoor Parking Areas †

Science.gov (United States)

Caballero-Gil, Cándido; Caballero-Gil, Pino; Molina-Gil, Jezabel

2016-01-01

This work proposes an adaptive recommendation mechanism for smart parking that takes advantage of the popularity of smartphones and the rise of the Internet of Things. The proposal includes a centralized system to forecast available indoor parking spaces, and a low-cost mobile application to obtain data of actual and predicted parking occupancy. The described scheme uses data from both sources bidirectionally so that the centralized forecast system is fed with data obtained with the distributed system based on smartphones, and vice versa. The mobile application uses different wireless technologies to provide the forecast system with actual parking data and receive from the system useful recommendations about where to park. Thus, the proposal can be used by any driver to easily find available parking spaces in indoor facilities. The client software developed for smartphones is a lightweight Android application that supplies precise indoor positioning systems based on Quick Response codes or Near Field Communication tags, and semi-precise indoor positioning systems based on Bluetooth Low Energy beacons. The performance of the proposed approach has been evaluated by conducting computer simulations and real experimentation with a preliminary implementation. The results have shown the strengths of the proposal in the reduction of the time and energy costs to find available parking spaces. PMID:27854282

Indoor location-based services prerequisites and foundations

CERN Document Server

Werner, Martin

2014-01-01

This book delivers concise coverage of classical methods and new developments related to indoor location-based services. It collects results from isolated domains including geometry, artificial intelligence, statistics, cooperative algorithms, and distributed systems and thus provides an accessible overview of fundamental methods and technologies. This makes it an ideal starting point for researchers, students, and professionals in pervasive computing. Location-based services are services using the location of a mobile computing device as their primary input. While such services are fairly e

Three-dimensional high-precision indoor positioning strategy using Tabu search based on visible light communication

Science.gov (United States)

Peng, Qi; Guan, Weipeng; Wu, Yuxiang; Cai, Ye; Xie, Canyu; Wang, Pengfei

2018-01-01

This paper proposes a three-dimensional (3-D) high-precision indoor positioning strategy using Tabu search based on visible light communication. Tabu search is a powerful global optimization algorithm, and the 3-D indoor positioning can be transformed into an optimal solution problem. Therefore, in the 3-D indoor positioning, the optimal receiver coordinate can be obtained by the Tabu search algorithm. For all we know, this is the first time the Tabu search algorithm is applied to visible light positioning. Each light-emitting diode (LED) in the system broadcasts a unique identity (ID) and transmits the ID information. When the receiver detects optical signals with ID information from different LEDs, using the global optimization of the Tabu search algorithm, the 3-D high-precision indoor positioning can be realized when the fitness value meets certain conditions. Simulation results show that the average positioning error is 0.79 cm, and the maximum error is 5.88 cm. The extended experiment of trajectory tracking also shows that 95.05% positioning errors are below 1.428 cm. It can be concluded from the data that the 3-D indoor positioning based on the Tabu search algorithm achieves the requirements of centimeter level indoor positioning. The algorithm used in indoor positioning is very effective and practical and is superior to other existing methods for visible light indoor positioning.

Fast Fingerprint Database Maintenance for Indoor Positioning Based on UGV SLAM

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Jian Tang

2015-03-01

Full Text Available Indoor positioning technology has become more and more important in the last two decades. Utilizing Received Signal Strength Indicator (RSSI fingerprints of Signals of OPportunity (SOP is a promising alternative navigation solution. However, as the RSSIs vary during operation due to their physical nature and are easily affected by the environmental change, one challenge of the indoor fingerprinting method is maintaining the RSSI fingerprint database in a timely and effective manner. In this paper, a solution for rapidly updating the fingerprint database is presented, based on a self-developed Unmanned Ground Vehicles (UGV platform NAVIS. Several SOP sensors were installed on NAVIS for collecting indoor fingerprint information, including a digital compass collecting magnetic field intensity, a light sensor collecting light intensity, and a smartphone which collects the access point number and RSSIs of the pre-installed WiFi network. The NAVIS platform generates a map of the indoor environment and collects the SOPs during processing of the mapping, and then the SOP fingerprint database is interpolated and updated in real time. Field tests were carried out to evaluate the effectiveness and efficiency of the proposed method. The results showed that the fingerprint databases can be quickly created and updated with a higher sampling frequency (5Hz and denser reference points compared with traditional methods, and the indoor map can be generated without prior information. Moreover, environmental changes could also be detected quickly for fingerprint indoor positioning.

Fine particles in homes of predominantly low-income families with children and smokers: Key physical and behavioral determinants to inform indoor-air-quality interventions.

Science.gov (United States)

Klepeis, Neil E; Bellettiere, John; Hughes, Suzanne C; Nguyen, Benjamin; Berardi, Vincent; Liles, Sandy; Obayashi, Saori; Hofstetter, C Richard; Blumberg, Elaine; Hovell, Melbourne F

2017-01-01

Children are at risk for adverse health outcomes from occupant-controllable indoor airborne contaminants in their homes. Data are needed to design residential interventions for reducing low-income children's pollutant exposure. Using customized air quality monitors, we continuously measured fine particle counts (0.5 to 2.5 microns) over a week in living areas of predominantly low-income households in San Diego, California, with at least one child (under age 14) and at least one cigarette smoker. We performed retrospective interviews on home characteristics, and particle source and ventilation activities occurring during the week of monitoring. We explored the relationship between weekly mean particle counts and interview responses using graphical visualization and multivariable linear regression (base sample n = 262; complete cases n = 193). We found associations of higher weekly mean particle counts with reports of indoor smoking of cigarettes or marijuana, as well as with frying food, using candles or incense, and house cleaning. Lower particle levels were associated with larger homes. We did not observe an association between lower mean particle counts and reports of opening windows, using kitchen exhaust fans, or other ventilation activities. Our findings about sources of fine airborne particles and their mitigation can inform future studies that investigate more effective feedback on residential indoor-air-quality and better strategies for reducing occupant exposures.

Fine particles in homes of predominantly low-income families with children and smokers: Key physical and behavioral determinants to inform indoor-air-quality interventions.

Directory of Open Access Journals (Sweden)

Neil E Klepeis

Full Text Available Children are at risk for adverse health outcomes from occupant-controllable indoor airborne contaminants in their homes. Data are needed to design residential interventions for reducing low-income children's pollutant exposure. Using customized air quality monitors, we continuously measured fine particle counts (0.5 to 2.5 microns over a week in living areas of predominantly low-income households in San Diego, California, with at least one child (under age 14 and at least one cigarette smoker. We performed retrospective interviews on home characteristics, and particle source and ventilation activities occurring during the week of monitoring. We explored the relationship between weekly mean particle counts and interview responses using graphical visualization and multivariable linear regression (base sample n = 262; complete cases n = 193. We found associations of higher weekly mean particle counts with reports of indoor smoking of cigarettes or marijuana, as well as with frying food, using candles or incense, and house cleaning. Lower particle levels were associated with larger homes. We did not observe an association between lower mean particle counts and reports of opening windows, using kitchen exhaust fans, or other ventilation activities. Our findings about sources of fine airborne particles and their mitigation can inform future studies that investigate more effective feedback on residential indoor-air-quality and better strategies for reducing occupant exposures.

Probabilistic Multi-Sensor Fusion Based Indoor Positioning System on a Mobile Device

Directory of Open Access Journals (Sweden)

Xiang He

2015-12-01

Full Text Available Nowadays, smart mobile devices include more and more sensors on board, such as motion sensors (accelerometer, gyroscope, magnetometer, wireless signal strength indicators (WiFi, Bluetooth, Zigbee, and visual sensors (LiDAR, camera. People have developed various indoor positioning techniques based on these sensors. In this paper, the probabilistic fusion of multiple sensors is investigated in a hidden Markov model (HMM framework for mobile-device user-positioning. We propose a graph structure to store the model constructed by multiple sensors during the offline training phase, and a multimodal particle filter to seamlessly fuse the information during the online tracking phase. Based on our algorithm, we develop an indoor positioning system on the iOS platform. The experiments carried out in a typical indoor environment have shown promising results for our proposed algorithm and system design.

Smartphone-Based Indoor Pedestrian Tracking Using Geo-Magnetic Observations

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Sungnam Lee

2013-01-01

Full Text Available With the widespread use of smartphones, the use of location-based services (LBS with smartphones has become an active research issue. The accurate measurement of user location is necessary to provide LBS. While outdoor locations are easily obtained with GPS, indoor location information is difficult to acquire. Previous work on indoor location tracking systems often relied on infrastructures that are influenced by environmental changes and temporal differences. Several studies have proposed infrastructure-less systems that are independent of the surroundings, but these works generally required non-trivial computation time or energy costs. In this paper, we propose an infrastructure-less pedestrian tracking system in indoor environments. The system uses accelerometers and magnetic sensors in smartphones without pre-installed infrastructure. We reduced the cumulative error of location tracking by geo-magnetic observations at corners and spots with magnetic fluctuations. In addition, we developed a robust estimation model that is tolerant to false positives, as well as a mobility model that reflects the characteristics of multiple sensors. Extensive evaluation in a real environment indicates that our system is accurate and cost-effective.

Location Fingerprint Extraction for Magnetic Field Magnitude Based Indoor Positioning

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Wenhua Shao

2016-01-01

Full Text Available Smartphone based indoor positioning has greatly helped people in finding their positions in complex and unfamiliar buildings. One popular positioning method is by utilizing indoor magnetic field, because this feature is stable and infrastructure-free. In this method, the magnetometer embedded on the smartphone measures indoor magnetic field and queries its position. However, the environments of the magnetometer are rather harsh. This harshness mainly consists of coarse-grained hard/soft-iron calibrations and sensor electronic noise. The two kinds of interferences decrease the position distinguishability of the magnetic field. Therefore, it is important to extract location features from magnetic fields to reduce these interferences. This paper analyzes the main interference sources of the magnetometer embedded on the smartphone. In addition, we present a feature distinguishability measurement technique to evaluate the performance of different feature extraction methods. Experiments revealed that selected fingerprints will improve position distinguishability.

Indoor air pollution

International Nuclear Information System (INIS)

Spengler, J.D.

1985-01-01

Although official efforts to control air pollution have traditionally focused on outdoor air, it is now apparent that elevated contaminant concentrations are common inside some private and public buildings. Concerns about potential public health problems due to indoor air pollution are based on evidence that urban residents typically spend more than 90 percent of their time indoors, concentrations of some contaminants are higher indoors than outdoors, and for some pollutants personal exposures are not characterized adequately by outdoor measurements. Among the more important indoor contaminants associated with health or irritation effects are passive tobacco smoke, radon decay products, carbon monoxide, nitrogen dioxide, formaldehyde, asbestos fibers, microorganisms and aeroallergens. Efforts to assess health risks associated with indoor air pollution are limited by insufficient information about the number of people exposed, the pattern and severity of exposures, and the health consequences of exposures. An overall strategy should be developed to investigate indoor exposures, health effects, control options, and public policy alternatives

The Dynamics of Daylighting at a Residential College Building with the Internal Courtyard Arrangement

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Adi Ainurzaman Jamaludin

2015-11-01

Full Text Available Dayasari residential college building was designed with the internal courtyard that allows for numerous implementations of bioclimatic design strategies, especially on daylighting. The field measurement was conducted at eight unoccupied student rooms, selected as samples to represent ten scenarios and orientations that concerned with the level of radiation and penetration of sunlight. This study reveals the contribution of the internal courtyard in the residential college which allows the daylight penetration at the corridor areas and interior of the rooms through the transom over the entrance door, up to ten hours daily. Different amounts of daylight were measured in specific room scenarios to suggest on the most comfortable indoor living space. The recorded mean value for indoor varied from 37 to 286 lux, while in the corridor area 192 to 3,848 lux. However, the use of the large overhangs over the windows, wall openings in the room and trees with large canopy in the landscape setting should critically justify when the adequacy of daylight was drastically reduced in certain rooms.

Indoor radon and its progeny levels in new type houses in rural area of Hubei

International Nuclear Information System (INIS)

He Quan; Xiong Zhaoxing; He Zuan; Zheng Youqing

1993-01-01

Using Cluster Sampling method, indoor radon of 54 rooms and radon progeny potential alpha-energy concentrations of 200 rooms were measured in the new type brick-concrete 2-storey flats and old type brick-wood single-storey residences in the rural area. Instant and cumulative samplings and measurements were made. The average per capita residential area of the surveyed houses was 28.1 m 2 , clear height 3.6 m. The geometric means of indoor radon concentration were 18.22 Bq.m -3 and 15.93 Bq.m -3 for storied and single-storey buildings, respectively; radon progeny potential alpha-energy concentrations were 2.62 mWL and 2.54 mWL, correspondingly. In storied buildings, the arithmetic mean of indoor cumulative radon concentration was 25.56 Bq.m -3 in summer, and 37.94 Bq.m -3 in winter. The annual effective dose equivalent of radon progeny inhaled indoors and outdoors was 0.80 mSv. (orig.). (6 refs., 1 fig., 5 tabs.)

Volatile organic compounds in indoor air: A review ofconcentrations measured in North America since 1990

Energy Technology Data Exchange (ETDEWEB)

ATHodgson@lbl.gov

2003-04-01

Central tendency and upper limit concentrations of volatile organic compounds (VOCs) measured in indoor air are summarized and reviewed. Data were obtained from published cross-sectional studies of residential and office buildings conducted in North America from 1990through the present. VOC concentrations in existing residences reported in 12 studies comprise the majority of the data set. Central tendency and maximum concentrations are compared between new and existing residences and between existing residences and office buildings. Historical changes in indoor VOC concentrations since the Clean Air Act Amendments of 1990 are explored by comparing the current data set with two published reviews of previous data obtained primarily in the 1980s. These historical comparisons suggest average indoor concentrations of some toxic air contaminants, such as 1,1,1-trichloroethane have decreased.

Chemical Emissions of Residential Materials and Products: Review of Available Information

Energy Technology Data Exchange (ETDEWEB)

Willem, Henry; Singer, Brett

2010-09-15

This report is prepared in the context of a larger program whose mission is to advance understanding of ventilation and indoor air quality in U.S. homes. A specific objective of this program is to develop the scientific basis ? through controlled experiments, monitoring and analysis ? for health risk-based ventilation standards. Appropriate and adequate ventilation is a basic element of a healthy home. Ventilation provides outdoor air and in the process removes indoor odors and contaminants including potentially unhealthful chemicals emitted by indoor materials, products and activities. Ventilation traditionally was assured to occur via infiltration of outdoor air through cracks and other leakage pathways in the residential building envelope. As building air tightness is improved for energy efficiency, infiltration can be reduced to inadequate levels. This has lead to the development of standards requiring mechanical ventilation. Though nominally intended to ensure acceptable indoor air quality, the standards are not explicitly tied to health risk or pollutant exposure targets. LBNL is currently designing analyses to assess the impact of varying ventilation standards on pollutant concentrations, health risks and energy use. These analyses require information on sources of chemical pollutant emissions, ideally including emission rates and the impact of ventilation on emissions. Some information can be obtained from recent studies that report measurements of various air contaminants and their concentrations in U.S. residences. Another way to obtain this information is the bottom-up approach of collecting and evaluating emissions data from construction and interior materials and common household products. This review contributes to the latter approach by summarizing available information on chemical emissions from new residential products and materials. We review information from the scientific literature and public sources to identify and discuss the databases that

An Indoor Location-Based Control System Using Bluetooth Beacons for IoT Systems.

Science.gov (United States)

Huh, Jun-Ho; Seo, Kyungryong

2017-12-19

The indoor location-based control system estimates the indoor position of a user to provide the service he/she requires. The major elements involved in the system are the localization server, service-provision client, user application positioning technology. The localization server controls access of terminal devices (e.g., Smart Phones and other wireless devices) to determine their locations within a specified space first and then the service-provision client initiates required services such as indoor navigation and monitoring/surveillance. The user application provides necessary data to let the server to localize the devices or allow the user to receive various services from the client. The major technological elements involved in this system are indoor space partition method, Bluetooth 4.0, RSSI (Received Signal Strength Indication) and trilateration. The system also employs the BLE communication technology when determining the position of the user in an indoor space. The position information obtained is then used to control a specific device(s). These technologies are fundamental in achieving a "Smart Living". An indoor location-based control system that provides services by estimating user's indoor locations has been implemented in this study (First scenario). The algorithm introduced in this study (Second scenario) is effective in extracting valid samples from the RSSI dataset but has it has some drawbacks as well. Although we used a range-average algorithm that measures the shortest distance, there are some limitations because the measurement results depend on the sample size and the sample efficiency depends on sampling speeds and environmental changes. However, the Bluetooth system can be implemented at a relatively low cost so that once the problem of precision is solved, it can be applied to various fields.

An Indoor Location-Based Control System Using Bluetooth Beacons for IoT Systems

Directory of Open Access Journals (Sweden)

Jun-Ho Huh

2017-12-01

Full Text Available The indoor location-based control system estimates the indoor position of a user to provide the service he/she requires. The major elements involved in the system are the localization server, service-provision client, user application positioning technology. The localization server controls access of terminal devices (e.g., Smart Phones and other wireless devices to determine their locations within a specified space first and then the service-provision client initiates required services such as indoor navigation and monitoring/surveillance. The user application provides necessary data to let the server to localize the devices or allow the user to receive various services from the client. The major technological elements involved in this system are indoor space partition method, Bluetooth 4.0, RSSI (Received Signal Strength Indication and trilateration. The system also employs the BLE communication technology when determining the position of the user in an indoor space. The position information obtained is then used to control a specific device(s. These technologies are fundamental in achieving a “Smart Living”. An indoor location-based control system that provides services by estimating user’s indoor locations has been implemented in this study (First scenario. The algorithm introduced in this study (Second scenario is effective in extracting valid samples from the RSSI dataset but has it has some drawbacks as well. Although we used a range-average algorithm that measures the shortest distance, there are some limitations because the measurement results depend on the sample size and the sample efficiency depends on sampling speeds and environmental changes. However, the Bluetooth system can be implemented at a relatively low cost so that once the problem of precision is solved, it can be applied to various fields.

Residential Central Air Conditioning and Heat Pump Installation – Workshop Outcomes

Energy Technology Data Exchange (ETDEWEB)

Goetzler, William [Navigant Consulting, Burlington, MA (United States); Zogg, Robert [Navigant Consulting, Burlington, MA (United States); Young, Jim [Navigant Consulting, Burlington, MA (United States); Bargach, Youssef [Navigant Consulting, Burlington, MA (United States)

2016-11-01

DOE's Building Technologies Office works with researchers and industry partners to develop and deploy technologies that can substantially reduce energy consumption in residential and commercial buildings. This report aims to advance BTO’s energy savings, emissions reduction, and other program goals by identifying research and development (R&D), demonstration and deployment, and other non-regulatory initiatives for improving the design and installation of residential central air conditioners (CAC) and central heat pumps (CHP). Improving the adoption of CAC/CHP design and installation best practices has significant potential to reduce equipment costs, improve indoor air quality and comfort, improve system performance, and most importantly, reduce household energy consumption and costs for heating and cooling by addressing a variety of common installation issues.

Association of Roadway Proximity with Indoor Air Pollution in a Peri-Urban Community in Lima, Peru

Directory of Open Access Journals (Sweden)

Lindsay J. Underhill

2015-10-01

Full Text Available The influence of traffic-related air pollution on indoor residential exposure is not well characterized in homes with high natural ventilation in low-income countries. Additionally, domestic allergen exposure is unknown in such populations. We conducted a pilot study of 25 homes in peri-urban Lima, Peru to estimate the effects of roadway proximity and season on residential concentrations. Indoor and outdoor concentrations of particulate matter (PM2.5, nitrogen dioxide (NO2, and black carbon (BC were measured OPEN ACCESS Int. J. Environ. Res. Public Health 2015, 12 13467 during two seasons, and allergens were measured in bedroom dust. Allergen levels were highest for dust mite and mouse allergens, with concentrations above clinically relevant thresholds in over a quarter and half of all homes, respectively. Mean indoor and outdoor pollutant concentrations were similar (PM2.5: 20.0 vs. 16.9 μg/m3, BC: 7.6 vs. 8.1 μg/m3, NO2: 7.3 vs. 7.5 ppb, and tended to be higher in the summer compared to the winter. Road proximity was significantly correlated with overall concentrations of outdoor PM2.5 (rs = −0.42, p = 0.01 and NO2 (rs = −0.36, p = 0.03, and outdoor BC concentrations in the winter (rs = −0.51, p = 0.03. Our results suggest that outdoor-sourced pollutants significantly influence indoor air quality in peri-urban Peruvian communities, and homes closer to roadways are particularly vulnerable.

Determining the ventilation and aerosol deposition rates from routine indoor-air measurements.

Science.gov (United States)

Halios, Christos H; Helmis, Costas G; Deligianni, Katerina; Vratolis, Sterios; Eleftheriadis, Konstantinos

2014-01-01

Measurement of air exchange rate provides critical information in energy and indoor-air quality studies. Continuous measurement of ventilation rates is a rather costly exercise and requires specific instrumentation. In this work, an alternative methodology is proposed and tested, where the air exchange rate is calculated by utilizing indoor and outdoor routine measurements of a common pollutant such as SO2, whereas the uncertainties induced in the calculations are analytically determined. The application of this methodology is demonstrated, for three residential microenvironments in Athens, Greece, and the results are also compared against ventilation rates calculated from differential pressure measurements. The calculated time resolved ventilation rates were applied to the mass balance equation to estimate the particle loss rate which was found to agree with literature values at an average of 0.50 h(-1). The proposed method was further evaluated by applying a mass balance numerical model for the calculation of the indoor aerosol number concentrations, using the previously calculated ventilation rate, the outdoor measured number concentrations and the particle loss rates as input values. The model results for the indoors' concentrations were found to be compared well with the experimentally measured values.

Towards Mobile Information Systems for Indoor Space

Directory of Open Access Journals (Sweden)

Xiaoxiang Zhang

2016-01-01

Full Text Available With the rapid development of Internet of things (IOT and indoor positioning technologies such as Wi-Fi and RFID, indoor mobile information systems have become a new research hotspot. Based on the unique features of indoor space and urgent needs on indoor mobile applications, in this paper we analyze some key issues in indoor mobile information systems, including positioning technologies in indoor environments, representation models for indoor spaces, query processing techniques for indoor moving objects, and index structures for indoor mobile applications. Then, we present an indoor mobile information management system named IndoorDB. Finally, we give some future research topics about indoor mobile information systems.

Influence of indoor air conditions on radon concentration in a detached house

International Nuclear Information System (INIS)

Akbari, Keramatollah; Mahmoudi, Jafar; Ghanbari, Mahdi

2013-01-01

Radon is released from soil and building materials and can accumulate in residential buildings. Breathing radon and radon progeny for extended periods hazardous to health and can lead to lung cancer. Indoor air conditions and ventilation systems strongly influence indoor radon concentrations. This paper focuses on effects of air change rate, indoor temperature and relative humidity on indoor radon concentrations in a one family detached house in Stockholm, Sweden. In this study a heat recovery ventilation system unit was used to control the ventilation rate and a continuous radon monitor (CRM) was used to measure radon levels. FLUENT, a computational fluid dynamics (CFD) software package was used to simulate radon entry into the building and air change rate, indoor temperature and relative humidity effects using a numerical approach. The results from analytical solution, measurements and numerical simulations showed that air change rate, indoor temperature and moisture had significant effects on indoor radon concentration. Increasing air change rate reduces radon level and for a specific air change rate (in this work Ach = 0.5) there was a range of temperature and relative humidity that minimized radon levels. In this case study minimum radon levels were obtained at temperatures between 20 and 22 °C and a relative humidity of 50–60%. - Highlights: ► We use CFD to simulate indoor radon concentration and distribution. ► The effects of ventilation rate, temperature and moisture are investigated. ► Model validation is performed through analytical solution and measurement results. ► Results show that ventilation rate is inversely proportional to radon level. ► There is a range of temperature and relative humidity that minimize radon level.

Adaptive Indoor Positioning Model Based on WLAN-Fingerprinting for Dynamic and Multi-Floor Environments

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Iyad Husni Alshami

2017-08-01

Full Text Available The Global Positioning System demonstrates the significance of Location Based Services but it cannot be used indoors due to the lack of line of sight between satellites and receivers. Indoor Positioning Systems are needed to provide indoor Location Based Services. Wireless LAN fingerprints are one of the best choices for Indoor Positioning Systems because of their low cost, and high accuracy, however they have many drawbacks: creating radio maps is time consuming, the radio maps will become outdated with any environmental change, different mobile devices read the received signal strength (RSS differently, and peoples’ presence in LOS between access points and mobile device affects the RSS. This research proposes a new Adaptive Indoor Positioning System model (called DIPS based on: a dynamic radio map generator, RSS certainty technique and peoples’ presence effect integration for dynamic and multi-floor environments. Dynamic in our context refers to the effects of people and device heterogeneity. DIPS can achieve 98% and 92% positioning accuracy for floor and room positioning, and it achieves 1.2 m for point positioning error. RSS certainty enhanced the positioning accuracy for floor and room for different mobile devices by 11% and 9%. Then by considering the peoples’ presence effect, the error is reduced by 0.2 m. In comparison with other works, DIPS achieves better positioning without extra devices.

Indoor tetrachloroethylene levels and determinants in Paris dwellings.

Science.gov (United States)

Roda, Célina; Kousignian, Isabelle; Ramond, Anna; Momas, Isabelle

2013-01-01

There is growing public health concern about indoor air quality. Tetrachloroethylene (PERC), a chlorinated volatile organic compound widely used as a solvent in dry cleaning facilities, can be a residential indoor air pollutant. As part of an environmental investigation included in the PARIS (Pollution and asthma Risk: an Infant Study) birth cohort, this study firstly aimed to document domestic PERC levels, and then to identify the factors influencing these levels using standardized questionnaires about housing characteristics and living conditions. Air samples were collected in the child's bedroom over one week using passive devices when infants were 1, 6, 9, and 12 months. PERC was identified and quantified by gas chromatography/mass spectrometry. PERC annual domestic level was calculated by averaging seasonal levels. PERC was omnipresent indoors, annual levels ranged from 0.6 to 124.2 μg/m3. Multivariate linear and logistic regression models showed that proximity to dry cleaning facilities, do-it-yourself activities (e.g.: photographic development, silverware), presence of air vents, and building construction date (<1945) were responsible for higher domestic levels of PERC. This study, conducted in an urban context, provides helpful information on PERC contamination in dwellings, and identifies parameters influencing this contamination. Copyright © 2012 Elsevier Inc. All rights reserved.

An Approach of Dynamic Object Removing for Indoor Mapping Based on UGV SLAM

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Jian Tang

2015-07-01

Full Text Available The study of indoor mapping for Location Based Service (LBS becomes more and more popular in recent years. LiDAR SLAM based mapping method seems to be a promising indoor mapping solution. However, there are some dynamic objects such as pedestrians, indoor vehicles, etc. existing in the raw LiDAR range data. They have to be removal for mapping purpose. In this paper, a new approach of dynamic object removing called Likelihood Grid Voting (LGV is presented. It is a model free method and takes full advantage of the high scanning rate of LiDAR, which is moving at a relative low speed in indoor environment. In this method, a counting grid is allocated for recording the occupation of map position by laser scans. The lower counter value of this position can be recognized as dynamic objects and the point cloud will be removed from map. This work is a part of algorithms in our self- developed Unmanned Ground Vehicles (UGV simultaneous localization and Mapping (SLAM system- NAVIS. Field tests are carried in an indoor parking place with NAVIS to evaluate the effectiveness of the proposed method. The result shows that all the small size objects like pedestrians can be detected and removed quickly; large size of objects like cars can be detected and removed partly.

Greenhouse gas emissions accounting of urban residential consumption: a household survey based approach.

Directory of Open Access Journals (Sweden)

Tao Lin

Full Text Available Devising policies for a low carbon city requires a careful understanding of the characteristics of urban residential lifestyle and consumption. The production-based accounting approach based on top-down statistical data has a limited ability to reflect the total greenhouse gas (GHG emissions from residential consumption. In this paper, we present a survey-based GHG emissions accounting methodology for urban residential consumption, and apply it in Xiamen City, a rapidly urbanizing coastal city in southeast China. Based on this, the main influencing factors determining residential GHG emissions at the household and community scale are identified, and the typical profiles of low, medium and high GHG emission households and communities are identified. Up to 70% of household GHG emissions are from regional and national activities that support household consumption including the supply of energy and building materials, while 17% are from urban level basic services and supplies such as sewage treatment and solid waste management, and only 13% are direct emissions from household consumption. Housing area and household size are the two main factors determining GHG emissions from residential consumption at the household scale, while average housing area and building height were the main factors at the community scale. Our results show a large disparity in GHG emissions profiles among different households, with high GHG emissions households emitting about five times more than low GHG emissions households. Emissions from high GHG emissions communities are about twice as high as from low GHG emissions communities. Our findings can contribute to better tailored and targeted policies aimed at reducing household GHG emissions, and developing low GHG emissions residential communities in China.

Greenhouse Gas Emissions Accounting of Urban Residential Consumption: A Household Survey Based Approach

Science.gov (United States)

Lin, Tao; Yu, Yunjun; Bai, Xuemei; Feng, Ling; Wang, Jin

2013-01-01

Devising policies for a low carbon city requires a careful understanding of the characteristics of urban residential lifestyle and consumption. The production-based accounting approach based on top-down statistical data has a limited ability to reflect the total greenhouse gas (GHG) emissions from residential consumption. In this paper, we present a survey-based GHG emissions accounting methodology for urban residential consumption, and apply it in Xiamen City, a rapidly urbanizing coastal city in southeast China. Based on this, the main influencing factors determining residential GHG emissions at the household and community scale are identified, and the typical profiles of low, medium and high GHG emission households and communities are identified. Up to 70% of household GHG emissions are from regional and national activities that support household consumption including the supply of energy and building materials, while 17% are from urban level basic services and supplies such as sewage treatment and solid waste management, and only 13% are direct emissions from household consumption. Housing area and household size are the two main factors determining GHG emissions from residential consumption at the household scale, while average housing area and building height were the main factors at the community scale. Our results show a large disparity in GHG emissions profiles among different households, with high GHG emissions households emitting about five times more than low GHG emissions households. Emissions from high GHG emissions communities are about twice as high as from low GHG emissions communities. Our findings can contribute to better tailored and targeted policies aimed at reducing household GHG emissions, and developing low GHG emissions residential communities in China. PMID:23405187

Electronic air cleaners and the indoor environment

International Nuclear Information System (INIS)

Krafthefer, B.

1986-01-01

The growing awareness over the quality of air in the indoor environment is driving the search for effective control methods for the contaminants of concern. Electronic air cleaners can control such pollutants as dust, pollen, tobacco smoke, radon decay products, and other particulates. This paper presents an examination of the various types of electronic air cleaners and their effects on indoor pollutants. It also examines the mechanism for contaminant removal, the relationship of the efficiency to the characteristics of the contaminant, and what type of contaminants can be controlled with the electronic air cleaner, with particular emphasis placed on the removal of radon decay products. From a study on radon product removal in residences, the electronic air cleaner was found to have an efficiency of up to 70%. Not only was there a reduction in the residential working level, but the fluctuations in the working level were also reduced. With this information, they can better understand how to solve the air treatment problem of the inhabited space. 17 references, 8 figures

BLE-BASED ACCURATE INDOOR LOCATION TRACKING FOR HOME AND OFFICE

OpenAIRE

Joonghong Park; Jaehoon Kim; Sungwon Kang

2015-01-01

Nowadays the use of smart mobile devices and the accompanying needs for emerging services relying on indoor location-based services (LBS) for mobile devices are rapidly increasing. For more accurate location tracking using Bluetooth Low Energy (BLE), this paper proposes a novel trilateration-based algorithm and presents experimental results that demonstrate its effectiveness.

Dairy farming: indoor v. pasture-based feeding

OpenAIRE

HOFSTETTER, P.; FREY, H.-J; GAZZARIN, C.; WYSS, U.; KUNZ, P.

2017-01-01

The current situation of volatile milk prices and rising costs of, e.g. grain and labour, suggests that it is worth studying productivity and efficiency in dairy farming. The objective of the current whole-system study, carried out in lowland Central Switzerland from 2007 to 2010, was to compare the performance, efficiency, land productivity and profitability of indoor-feeding (IF) dairy production with that of pasture-based feeding (PF) dairy production. An IF herd consisting of 11 Holstein-...

INEMO: Distributed RF-Based Indoor Location Determination with Confidence Indicator

Directory of Open Access Journals (Sweden)

Youxian Sun

2007-12-01

Full Text Available Using radio signal strength (RSS in sensor networks localization is an attractive method since it is a cost-efficient method to provide range indication. In this paper, we present a two-tier distributed approach for RF-based indoor location determination. Our approach, namely, INEMO, provides positioning accuracy of room granularity and office cube granularity. A target can first give a room granularity request and the background anchor nodes cooperate to accomplish the positioning process. Anchors in the same room can give cube granularity if the target requires further accuracy. Fixed anchor nodes keep monitoring status of nearby anchors and local reference matching is used to support room separation. Furthermore, we utilize the RSS difference to infer the positioning confidence. The simulation results demonstrate the efficiency of the proposed RF-based indoor location determination.

In-situ real time measurements of thermal comfort and comparison with the adaptive comfort theory in Dutch residential dwellings

NARCIS (Netherlands)

Ioannou, A.; Itard, L.C.M.; Agarwal, Tushar

2018-01-01

Indoor thermal comfort is generally assessed using the PMV or the adaptive model. This research presents the results obtained by in-situ real time measurements of thermal comfort and thermal comfort perception in 17 residential dwellings in the Netherlands. The study demonstrates the new

Standard values of fugacity for sulfur which are self-consistent with the low-pressure phase diagram

Energy Technology Data Exchange (ETDEWEB)

Marriott, Robert A., E-mail: rob.marriott@ucalgary.ca [Alberta Sulphur Research Ltd., University of Calgary, Alberta (Canada); Wan, Herman H. [Alberta Sulphur Research Ltd., University of Calgary, Alberta (Canada)

2011-08-15

Highlights: > We have provided a method for calculating the fugacity for elemental sulfur. > Calculated sulfur fugacities can be used in sulfur equilibrium models. > The sulfur fugacities also can be used to locate the phase changes in the low-pressure phase diagram. > We have measured the 'natural' melting point of sulfur, and found it to be T = 388.5 {+-} 0.2 K. - Abstract: A method for calculating the fugacity of pure sulfur in the {alpha}-solid, {beta}-solid and liquid phase regions has been reported for application to industrial equilibrium conditions, e.g., high-pressure solubility of sulfur in sour gas. The fugacity calculations are self-consistent with the low-pressure phase diagram. As recently discussed by Ferreira and Lobo , empirical fitting of the experimental data does not yield consistent behaviour for the low-pressure phase diagram of elemental sulfur. In particular, there is a discrepancy between the vapour pressure of {beta}-solid (monoclinic) and liquid sulfur at the fusion temperature. We have provided an alternative semi-empirical approach which allows one to calculate values of the fugacity at conditions removed from the conditions of the pure sulfur phase transitions. For our approach, we have forced the liquid vapour pressure to equal the {beta}-solid vapour pressure at the {beta}-l-g triple point corresponding to the 'natural' fusion temperature for {beta}-solid. Many studies show a higher 'observed' fusion temperature for elemental sulfur. The non-reversible conditions for 'observed' fusion conditions for elemental sulfur result from a kinetically hindered melt which causes some thermodynamic measurements to be related to a metastable S{sub 8} liquid. We have measured the 'natural' fusion temperature, T{sub fus}{sup {beta}}(exp.)=(388.5{+-}0.2)K at p = 89.9 kPa, which is consistent with literature fusion data at higher-pressures. Using our semi-empirical approach, we have used or found the

The Effect of Roof Angles on Indoor Air Temperatures in Terrace Houses in Malaysia

Directory of Open Access Journals (Sweden)

A. B. Ramly

2006-12-01

Full Text Available The main aim of energy efficiency in building design is to create buildings that utilise minimum amount of energy while meeting the comfort standards as high as or higher than those provided by conventional buildings.To achieve these standards, it is necessary to study the local environment in order to assess its positive and negative features (impact on the building. The results will provide a basic understanding of heat transfer and human thermal comfort requirements. It also provides foundation for which an energy efficient design of buildings can be established. The design of residential buildings has a significant impact on everyday lives of people. It includes the types and forms of buildings that are commonly occupied by people. In Malaysia, the 'terrace house' constitutes the majority of the residential building stock on which this study is based. The study considers the effects of the different roof angles on reducing solar gain and indoor temperatures through eight directions within 24 hours. To analyse and explain that effect, five different angles of roof were chosen for the simulations. In general, all the angles were chosen due 10 their architectural design characteristics. These angles start from 0 degree as a horizontal flat roof to 60 degrees, i.e. increment of every 15 degrees. The research is seen as providing a tool in evaluating the dynamic indoor air temperature and the effect of roof angles. The evaluation is derived from a series of computer simulations using commercially available software called BLAST.

INDOOR LOCALIZATION USING WI-FI BASED FINGERPRINTING AND TRILATERATION TECHIQUES FOR LBS APPLICATIONS

Directory of Open Access Journals (Sweden)

S. Chan

2012-06-01

Full Text Available The past few years have seen wide spread adoption of outdoor positioning services, mainly GPS, being incorporated into everyday devices such as smartphones and tablets. While outdoor positioning has been well received by the public, its indoor counterpart has been mostly limited to private use due to its higher costs and complexity for setting up the proper environment. The objective of this research is to provide an affordable mean for indoor localization using wireless local area network (WLAN Wi-Fi technology. We combined two different Wi-Fi approaches to locate a user. The first method involves the use of matching the pre-recorded received signal strength (RSS from nearby access points (AP, to the data transmitted from the user on the fly. This is commonly known as "fingerprint matching". The second approach is a distance-based trilateration approach using three known AP coordinates detected on the user's device to derive the position. The combination of the two steps enhances the accuracy of the user position in an indoor environment allowing location-based services (LBS such as mobile augmented reality (MAR to be deployed more effectively in the indoor environment. The mapping of the RSS map can also prove useful to IT planning personnel for covering locations with no Wi-Fi coverage (ie. dead spots. The experiments presented in this research helps provide a foundation for the integration of indoor with outdoor positioning to create a seamless transition experience for users.

Indoor Localization Using Wi-Fi Based Fingerprinting and Trilateration Techiques for Lbs Applications

Science.gov (United States)

Chan, S.; Sohn, G.

2012-06-01

The past few years have seen wide spread adoption of outdoor positioning services, mainly GPS, being incorporated into everyday devices such as smartphones and tablets. While outdoor positioning has been well received by the public, its indoor counterpart has been mostly limited to private use due to its higher costs and complexity for setting up the proper environment. The objective of this research is to provide an affordable mean for indoor localization using wireless local area network (WLAN) Wi-Fi technology. We combined two different Wi-Fi approaches to locate a user. The first method involves the use of matching the pre-recorded received signal strength (RSS) from nearby access points (AP), to the data transmitted from the user on the fly. This is commonly known as "fingerprint matching". The second approach is a distance-based trilateration approach using three known AP coordinates detected on the user's device to derive the position. The combination of the two steps enhances the accuracy of the user position in an indoor environment allowing location-based services (LBS) such as mobile augmented reality (MAR) to be deployed more effectively in the indoor environment. The mapping of the RSS map can also prove useful to IT planning personnel for covering locations with no Wi-Fi coverage (ie. dead spots). The experiments presented in this research helps provide a foundation for the integration of indoor with outdoor positioning to create a seamless transition experience for users.

PARAMETER ESTIMATION AND MODEL SELECTION FOR INDOOR ENVIRONMENTS BASED ON SPARSE OBSERVATIONS

Directory of Open Access Journals (Sweden)

Y. Dehbi

2017-09-01

Full Text Available This paper presents a novel method for the parameter estimation and model selection for the reconstruction of indoor environments based on sparse observations. While most approaches for the reconstruction of indoor models rely on dense observations, we predict scenes of the interior with high accuracy in the absence of indoor measurements. We use a model-based top-down approach and incorporate strong but profound prior knowledge. The latter includes probability density functions for model parameters and sparse observations such as room areas and the building footprint. The floorplan model is characterized by linear and bi-linear relations with discrete and continuous parameters. We focus on the stochastic estimation of model parameters based on a topological model derived by combinatorial reasoning in a first step. A Gauss-Markov model is applied for estimation and simulation of the model parameters. Symmetries are represented and exploited during the estimation process. Background knowledge as well as observations are incorporated in a maximum likelihood estimation and model selection is performed with AIC/BIC. The likelihood is also used for the detection and correction of potential errors in the topological model. Estimation results are presented and discussed.

Parameter Estimation and Model Selection for Indoor Environments Based on Sparse Observations

Science.gov (United States)

Dehbi, Y.; Loch-Dehbi, S.; Plümer, L.

2017-09-01

This paper presents a novel method for the parameter estimation and model selection for the reconstruction of indoor environments based on sparse observations. While most approaches for the reconstruction of indoor models rely on dense observations, we predict scenes of the interior with high accuracy in the absence of indoor measurements. We use a model-based top-down approach and incorporate strong but profound prior knowledge. The latter includes probability density functions for model parameters and sparse observations such as room areas and the building footprint. The floorplan model is characterized by linear and bi-linear relations with discrete and continuous parameters. We focus on the stochastic estimation of model parameters based on a topological model derived by combinatorial reasoning in a first step. A Gauss-Markov model is applied for estimation and simulation of the model parameters. Symmetries are represented and exploited during the estimation process. Background knowledge as well as observations are incorporated in a maximum likelihood estimation and model selection is performed with AIC/BIC. The likelihood is also used for the detection and correction of potential errors in the topological model. Estimation results are presented and discussed.

When and where do hip fractures occur? A population-based study.

Science.gov (United States)

Leavy, B; Åberg, A C; Melhus, H; Mallmin, H; Michaëlsson, K; Byberg, L

2013-09-01

We investigated the effects of socio-demographic and health factors on timing and location of hip fracture among 484 subjects. Time of fracture varied between community dwellers and residential care facility dwellers, and in relation to subjects' psychotropic drug status. Indoor hip fracture incidence increased on snow-covered days. This paper aims to describe the timing and whereabouts of hip fracture cases in a population-based setting and to relate these factors with residential and health status, seasonal variation, and snow-covered ground. We consecutively included 484 incident hip fracture events (age ≥50 years) admitted to a Swedish orthopedic department during a 1-year period. Data concerning socio-demographic details, fall location, time of fracture, comorbidity, and medications were collected from in-patient medical records and through patient or caregiver interviews. The expected peak in fracture occurrence during daytime was observed among community dwellers but not among subjects living in residential care. Hip fracture was twice as likely to occur during nighttime hours among psychotropic drug users (adjusted odds ratio (Adj. OR), 2.20; 95% confidence interval (CI), 1.12-4.30) compared to those not receiving these medications. Subjects without dementia, taking psychotropic drugs, were also more likely to fracture during nighttime hours (Adj. OR, 2.91; 95% CI, 1.40-6.0). We observed an increase in indoor hip fracture incidence on snow-covered days among community dwellers (incidence rate ratio, 1.34; 95% CI, 1.02-1.74). We observed only a weak seasonal trend in hip fracture incidence, based on month, among community dwellers who fractured indoors. Special attention and possibly fall-preventive efforts should be directed not only toward those living in residential care facilities but also toward community-dwelling subjects taking psychotropic drugs since these groups have a higher incidence of nighttime hip fracture. Further research aiming to explain

Reduction of outdoor and indoor ambient dose equivalent after decontamination in the Fukushima evacuation zones

International Nuclear Information System (INIS)

Yoshida-Ohuchi, Hiroko; Kanagami, Takashi; Naitoh, Yutaka; Kameyama, Mizuki; Hosoda, Masahiro

2017-01-01

One of the most urgent issues following the accident at the Fukushima Daiichi nuclear power plant (FDNPP) was the remediation of the land, in particular, for residential area contaminated by the radioactive materials discharged. In this study, the effect of decontamination on reduction of ambient dose equivalent outdoors and indoors was evaluated. The latter is essential for residents as most individuals spend a large portion of their time indoors. From December 2012 to November 2014, thirty-seven Japanese single-family detached wooden houses were investigated before and after decontamination in evacuation zones. Outdoor and indoor dose measurements (n=84 and 114, respectively) were collected based on in situ measurements using the NaI (Tl) scintillation surveymeter. The outdoor ambient dose equivalents [H"*(10)_o_u_t] ranged from 0.61 to 3.71 μSv h"-"1 and from 0.23 to 1.32 μSv h"-"1 before and after decontamination, respectively. The indoor ambient dose equivalents [H"*(10)"i"n] ranged from 0.29 to 2.53 μSv h"-"1 and from 0.16 to 1.22 μSv h"-"1 before and after decontamination, respectively. The values of reduction efficiency (RE), defined as the ratio by which the radiation dose has been reduced via decontamination, were evaluated as 0.47±0.13, 0.51±0.13, and 0.58±0.08 (average±σ) when H"*(10)_o_u_t <1.0 μSv h"-"1, 1.0 μSv h"-"1 < H"*(10)_o_u_t <2.0 μSv h"-"1, and 2.0 μSv h"-"1< H"*(10)_o_u_t, respectively, indicating the values of RE increased as H"*(10)_o_u_t increased. It was found that the values of RE were 0.53±0.12 outdoors and 0.41±0.09 indoors, respectively, indicating RE was larger outdoors than indoors. Indoor dose is essential as most individuals spend a large portion of their time indoors. The difference between outdoors and indoors should be considered carefully in order to estimate residents’ exposure dose before their returning home

Reduction of outdoor and indoor ambient dose equivalent after decontamination in the Fukushima evacuation zones

Energy Technology Data Exchange (ETDEWEB)

Yoshida-Ohuchi, Hiroko; Kanagami, Takashi [Graduate School of Pharmaceutical Sciences, Tohoku University, Miyagi (Japan); Naitoh, Yutaka; Kameyama, Mizuki [Japan Environment Research Co., Ltd., Miyagi (Japan); Hosoda, Masahiro [Dept. of Radiological Life Sciences, Hirosaki University Graduate School of Health Sciences, Aomori (Japan)

2017-03-15

One of the most urgent issues following the accident at the Fukushima Daiichi nuclear power plant (FDNPP) was the remediation of the land, in particular, for residential area contaminated by the radioactive materials discharged. In this study, the effect of decontamination on reduction of ambient dose equivalent outdoors and indoors was evaluated. The latter is essential for residents as most individuals spend a large portion of their time indoors. From December 2012 to November 2014, thirty-seven Japanese single-family detached wooden houses were investigated before and after decontamination in evacuation zones. Outdoor and indoor dose measurements (n=84 and 114, respectively) were collected based on in situ measurements using the NaI (Tl) scintillation surveymeter. The outdoor ambient dose equivalents [H{sup *}(10){sub out}] ranged from 0.61 to 3.71 μSv h{sup -1} and from 0.23 to 1.32 μSv h{sup -1} before and after decontamination, respectively. The indoor ambient dose equivalents [H{sup *}(10){sup in}] ranged from 0.29 to 2.53 μSv h{sup -1} and from 0.16 to 1.22 μSv h{sup -1} before and after decontamination, respectively. The values of reduction efficiency (RE), defined as the ratio by which the radiation dose has been reduced via decontamination, were evaluated as 0.47±0.13, 0.51±0.13, and 0.58±0.08 (average±σ) when H{sup *}(10){sub out} <1.0 μSv h{sup -1}, 1.0 μSv h{sup -1} indoors, respectively, indicating RE was larger outdoors than indoors. Indoor dose is essential as most individuals spend a large portion of their time indoors. The difference between outdoors and indoors should be considered carefully in order to estimate residents’ exposure dose before their returning home.

INDOOR-OUTDOOR AEROSOL CONCENTRATIONS IN TWO PORTUGUESE CITIES AND THE GLOBAL WARMING SCENARIO

Energy Technology Data Exchange (ETDEWEB)

Antonio F. Miguel; A. Heitor Reis [Department of Physics, University of Evora (Portugal); Marta Melgao [Geophysics Centre of Evora (Portugal)

2008-09-30

Aerosols play a major role both in climate change and in air quality. They affect climate through interfering with radiative transfer and hence the atmospheric temperature, and also the air quality. Many epidemiological studies have confirmed that a relation exists between elevated aerosol particle concentration and adverse human health effects. Aerosol particle number and size distributions were measured both indoors and outdoors in the urban areas of Evora and Lisbon. We investigated the indoor-to-outdoor relationship of aerosol particles and the aerosol size distributions. The impact of the occurrence of a residential fire in the aerosol size distribution is also analyzed. Finally, we speculate of how global increase in temperature can affect concentration of aerosols in the atmosphere, via increased boundary layer convection.

The mutagenicity of indoor air particles in a residential pilot field study: Application and evaluation of new methodologies

Science.gov (United States)

Lewtas, Joellen; Goto, Sumio; Williams, Katherine; Chuang, Jane C.; Petersen, Bruce A.; Wilson, Nancy K.

The mutagenicity of indoor air paniculate matter has been measured in a pilot field study of homes in Columbus, Ohio during the 1984 winter. The study was conducted in eight all natural-gas homes and two all electric homes. Paniculate matter and semi-volatile organic compounds were collected indoors using a medium volume sampler. A micro-forward mutation bioassay employing Salmonella typhimurium strain TM 677 was used to quantify the mutagenicity in solvent extracts of microgram quantities of indoor air particles. The mutagenicity was quantified in terms of both mutation frequency per mg of organic matter extracted and per cubic meter of air sampled. The combustion source variables explored in this study included woodburning in fireplaces and cigarette smoking. Homes in which cigarette smoking occurred had the highest concentrations of mutagenicity per cubic meter of air. The average indoor air mutagenicity per cubic meter was highly correlated with the number of cigarettes smoked. When the separate sampling periods in each room were compared, the mutagenicity in the kitchen samples was the most highly correlated with the number of cigarettes smoked.

Design and optimization of zero-energy-consumption based solar energy residential building systems

Science.gov (United States)

Zheng, D. L.; Yu, L. J.; Tan, H. W.

2017-11-01

Energy consumption of residential buildings has grown fast in recent years, thus raising a challenge on zero energy residential building (ZERB) systems, which aim at substantially reducing energy consumption of residential buildings. Thus, how to facilitate ZERB has become a hot but difficult topic. In the paper, we put forward the overall design principle of ZERB based on analysis of the systems’ energy demand. In particular, the architecture for both schematic design and passive technology is optimized and both energy simulation analysis and energy balancing analysis are implemented, followed by committing the selection of high-efficiency appliance and renewable energy sources for ZERB residential building. In addition, Chinese classical residential building has been investigated in the proposed case, in which several critical aspects such as building optimization, passive design, PV panel and HVAC system integrated with solar water heater, Phase change materials, natural ventilation, etc., have been taken into consideration.

The Smartphone-Based Offline Indoor Location Competition at IPIN 2016: Analysis and Future Work

Directory of Open Access Journals (Sweden)

Joaquín Torres-Sospedra

2017-03-01

Full Text Available This paper presents the analysis and discussion of the off-site localization competition track, which took place during the Seventh International Conference on Indoor Positioning and Indoor Navigation (IPIN 2016. Five international teams proposed different strategies for smartphone-based indoor positioning using the same reference data. The competitors were provided with several smartphone-collected signal datasets, some of which were used for training (known trajectories, and others for evaluating (unknown trajectories. The competition permits a coherent evaluation method of the competitors’ estimations, where inside information to fine-tune their systems is not offered, and thus provides, in our opinion, a good starting point to introduce a fair comparison between the smartphone-based systems found in the literature. The methodology, experience, feedback from competitors and future working lines are described.

Spatial sparsity based indoor localization in wireless sensor network for assistive healthcare.

Science.gov (United States)

Pourhomayoun, Mohammad; Jin, Zhanpeng; Fowler, Mark

2012-01-01

Indoor localization is one of the key topics in the area of wireless networks with increasing applications in assistive healthcare, where tracking the position and actions of the patient or elderly are required for medical observation or accident prevention. Most of the common indoor localization methods are based on estimating one or more location-dependent signal parameters like TOA, AOA or RSS. However, some difficulties and challenges caused by the complex scenarios within a closed space significantly limit the applicability of those existing approaches in an indoor assistive environment, such as the well-known multipath effect. In this paper, we develop a new one-stage localization method based on spatial sparsity of the x-y plane. In this method, we directly estimate the location of the emitter without going through the intermediate stage of TOA or signal strength estimation. We evaluate the performance of the proposed method using Monte Carlo simulation. The results show that the proposed method is (i) very accurate even with a small number of sensors and (ii) very effective in addressing the multi-path issues.

Indoor Pedestrian Navigation Based on Hybrid Route Planning and Location Modeling

DEFF Research Database (Denmark)

Schougaard, Kari Rye; Grønbæk, Kaj; Scharling, Tejs

2012-01-01

This paper introduces methods and services called PerPosNav for development of custom indoor pedestrian navigation applications to be deployed on a variety of platforms. PerPosNav combines symbolic and geometry based modeling of buildings, and in turn combines graph-based and geometric route...

Design of an Indoor Sonic Boom Simulator at NASA Langley Research Center

Science.gov (United States)

Klos, Jacob; Sullivan, Brenda M.; Shepherd, Kevin P.

2008-01-01

Construction of a simulator to recreate the soundscape inside residential buildings exposed to sonic booms is scheduled to start during the summer of 2008 at NASA Langley Research Center. The new facility should be complete by the end of the year. The design of the simulator allows independent control of several factors that create the indoor soundscape. Variables that will be isolated include such factors as boom duration, overpressure, rise time, spectral shape, level of rattle, level of squeak, source of rattle and squeak, level of vibration and source of vibration. Test subjects inside the simulator will be asked to judge the simulated soundscape, which will represent realistic indoor boom exposure. Ultimately, this simulator will be used to develop a functional relationship between human response and the sound characteristics creating the indoor soundscape. A conceptual design has been developed by NASA personnel, and is currently being vetted through small-scale risk reduction tests that are being performed in-house. The purpose of this document is to introduce the conceptual design, identify how the indoor response will be simulated, briefly outline some of the risk reduction tests that have been completed to vet the design, and discuss the impact of these tests on the simulator design.

Resident's Floor Level Preference in High-Rise Residential Buildings in China: A Case Study of Shijiazhuang City,Hebei Province

Institute of Scientific and Technical Information of China (English)

Sun Pingjun; Wang Ying; Pang Ruiqiu; Song Xinyan

2016-01-01

With the constant advance of global urbanization and aggravation of urban construction land scarcity,high-rise residential buildings have become one of the main carriers of urban residential function on account of both land saving and large housing requirement.However,relevant studies on consumers' floor selection preference in high-rise residential buildings,regarding what inherent and regular features and causes it has,are still insufficient,despite that related issues have important practical significance for real estate developers and designers' decision making in terms of dwelling size ratio,floor area,indoor layout,and so on.This study,based on systematic examination of existing domestic and international researches,seeks to make empirical tests and generalization on the above issues from the aspect of"utility function" (safety,comfortableness,accessibility and economic efficiency) of the living environment that impacted by different floor levels,and floor selection features regarding consumers' social and family structure attributes,as well as the intrinsic correlation between them.The results show the existence of floor level preference in high-rise residential buildings.Its essence is a personalized characterization of consumers' social and family structures' attributes in selecting the "utility function" of the living environment,as the preference value differs under various attributes including gender,age,income,family members and others.

A New Three-Dimensional Indoor Positioning Mechanism Based on Wireless LAN

Directory of Open Access Journals (Sweden)

Jiujun Cheng

2014-01-01

Full Text Available The researches on two-dimensional indoor positioning based on wireless LAN and the location fingerprint methods have become mature, but in the actual indoor positioning situation, users are also concerned about the height where they stand. Due to the expansion of the range of three-dimensional indoor positioning, more features must be needed to describe the location fingerprint. Directly using a machine learning algorithm will result in the reduced ability of classification. To solve this problem, in this paper, a “divide and conquer” strategy is adopted; that is, first through k-medoids algorithm the three-dimensional location space is clustered into a number of service areas, and then a multicategory SVM with less features is created for each service area for further positioning. Our experiment shows that the error distance resolution of the approach with k-medoids algorithm and multicategory SVM is higher than that of the approach only with SVM, and the former can effectively decrease the “crazy prediction.”

On the use of a risk ladder: Linking public perception of risks associated with indoor air with cognitive elements and attitudes toward risk reduction

Science.gov (United States)

Moschandreas, D. J.; Chang, P. E.

In recent years a number of building managers have invested small amounts of money to measure indoor air quality in offices and other non-industrial buildings. Their objective is to reduce the number of occupant complaints, and not necessarily to reduce the risk associated with such complaints. Clearly, reduction of the risk would require greater investment of funds and effort. This paper focuses on individuals and the amount of money they are willing to invest in order to reduce risks associated with indoor air pollution in their home. Psychologists assert that lay judgement of risks are influenced by cognitive biases and attitudes. This study investigates the possibility that cognitive elements and general attitudes influence not only the perceived risk associated with exposures to indoor air pollutants, but also the willingness of individuals to invest in order to reduce the risk. A three-stage study was performed to determine some of the factors that influence public decisions to control the quality of the air inside their home. The study is focused on the design of a risk ladder, and the survey of 400 randomly selected individuals in the Chicago metropolitan area. The survey was designed to determine if demographics, smoking, education, or income influence the desire of individuals to invest in order to reduce indoor air pollution. The following conclusions were reached: (i) public awareness of indoor air pollution is high; (ii) media campaigns on indoor air pollution affect the determination of the specific pollutant the public perceives as important, but do not influence the public's desire to invest larger amounts of money to reduce risks from exposures to air pollutants in the residential environment; (iii) the public is not willing to spend large amounts of money to reduce indoor residential air pollution; (iv) education does not affect the level of awareness regarding indoor air pollution, but it increases the willingness to invest in an effort to reduce

An Indoor Tracking System Based on Bluetooth Technology

OpenAIRE

Opoku, Samuel King

2012-01-01

Implementations of tracking systems have become prevalent issues in modern technology due to its advantage of location detection of objects. Objects are usually tracked using trackers based on GPS, GSM, RFID and Bluetooth signal strength implementation. These mechanisms usually require line of sight operations, limited coverage and low level programming language for accessing Bluetooth signal strength. This paper presents an alternative technique for tracking the movement of indoor objects ba...

A Map/INS/Wi-Fi Integrated System for Indoor Location-Based Service Applications.

Science.gov (United States)

Yu, Chunyang; Lan, Haiyu; Gu, Fuqiang; Yu, Fei; El-Sheimy, Naser

2017-06-02

In this research, a new Map/INS/Wi-Fi integrated system for indoor location-based service (LBS) applications based on a cascaded Particle/Kalman filter framework structure is proposed. Two-dimension indoor map information, together with measurements from an inertial measurement unit (IMU) and Received Signal Strength Indicator (RSSI) value, are integrated for estimating positioning information. The main challenge of this research is how to make effective use of various measurements that complement each other in order to obtain an accurate, continuous, and low-cost position solution without increasing the computational burden of the system. Therefore, to eliminate the cumulative drift caused by low-cost IMU sensor errors, the ubiquitous Wi-Fi signal and non-holonomic constraints are rationally used to correct the IMU-derived navigation solution through the extended Kalman Filter (EKF). Moreover, the map-aiding method and map-matching method are innovatively combined to constrain the primary Wi-Fi/IMU-derived position through an Auxiliary Value Particle Filter (AVPF). Different sources of information are incorporated through a cascaded structure EKF/AVPF filter algorithm. Indoor tests show that the proposed method can effectively reduce the accumulation of positioning errors of a stand-alone Inertial Navigation System (INS), and provide a stable, continuous and reliable indoor location service.

Indoor Air Quality and Ventilation in Residential Deep Energy Retrofits

Energy Technology Data Exchange (ETDEWEB)

Less, Brennan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2014-06-01

Because airtightening is a significant part of Deep Energy Retrofits (DERs), concerns about ventilation and Indoor Air Quality (IAQ) have emerged. To investigate this, ventilation and IAQ were assessed in 17 non-smoking California Deep Energy Retrofit homes. Inspections and surveys were used to assess household activities and ventilation systems. Pollutant sampling performed in 12 homes included six-day passive samples of nitrogen dioxide (NO₂), formaldehyde and air exchange rate (AER); time-resolved data loggers were used to measure particle counts. Half of the homes provided continuous mechanical ventilation. Despite these homes being twice as airtight (3.0 and 7.6 ACH50, respectively), their median AER was indistinguishable from naturally vented homes (0.36 versus 0.37 hr^-1). Numerous problems were found with ventilation systems; however, pollutant levels did not reach levels of concern in most homes. Ambient NO₂ standards were exceeded in some gas cooking homes that used legacy ranges with standing pilots, and in Passive House-style homes without range hoods exhausted to outside. Cooking exhaust systems were installed and used inconsistently. The majority of homes reported using low-emitting materials, and formaldehyde levels were approximately half those in conventional new CA homes (19.7 versus 36 μg/m³), with emissions rates nearly 40percent less (12.3 versus 20.6 μg/m²/hr.). Presence of air filtration systems led to lower indoor particle number concentrations (PN_>0.5: 8.80E+06 PN/m³ versus 2.99E+06; PN_>2.5: 5.46E+0.5 PN/m³ versus 2.59E+05). The results indicate that DERs can provide adequate ventilation and IAQ, and that DERs should prioritize source control, particle filtration and well-designed local exhaust systems, while still providing adequate continuous ventilation.

Estimating the risk of lung cancer from inhalation of radon daughters indoors: review and evaluation. Final report, October 1986-April 1988

International Nuclear Information System (INIS)

Borak, T.B.; Johnson, J.A.

1988-06-01

A review of the dosimetric models and epidemiological studies with regard to the relation between indoor radon exposure and lung cancer indicates that the Working Level is an appropriate unit for indoor radon exposure; that the uncertainty in applying risk estimates derived from uranium miner data may be reduced by determining nose vs. mouth breathing ratios, residential aerosol characteristics, and lung cancer risk vs. age at exposure; that there is persuasive evidence of an association between radon exposure indoors and lung cancer; and that epidemiological studies in progress may provide a basis for revision or validation of current models but only is experimental designs are employed that will permit pooling of data to obtain greater statistical power

An Indoor Location-Based Control System Using Bluetooth Beacons for IoT Systems

OpenAIRE

Jun-Ho Huh; Kyungryong Seo

2017-01-01

The indoor location-based control system estimates the indoor position of a user to provide the service he/she requires. The major elements involved in the system are the localization server, service-provision client, user application positioning technology. The localization server controls access of terminal devices (e.g., Smart Phones and other wireless devices) to determine their locations within a specified space first and then the service-provision client initiates required services such...

Laser-Based Slam with Efficient Occupancy Likelihood Map Learning for Dynamic Indoor Scenes

Science.gov (United States)

Li, Li; Yao, Jian; Xie, Renping; Tu, Jinge; Feng, Chen

2016-06-01

Location-Based Services (LBS) have attracted growing attention in recent years, especially in indoor environments. The fundamental technique of LBS is the map building for unknown environments, this technique also named as simultaneous localization and mapping (SLAM) in robotic society. In this paper, we propose a novel approach for SLAMin dynamic indoor scenes based on a 2D laser scanner mounted on a mobile Unmanned Ground Vehicle (UGV) with the help of the grid-based occupancy likelihood map. Instead of applying scan matching in two adjacent scans, we propose to match current scan with the occupancy likelihood map learned from all previous scans in multiple scales to avoid the accumulation of matching errors. Due to that the acquisition of the points in a scan is sequential but not simultaneous, there unavoidably exists the scan distortion at different extents. To compensate the scan distortion caused by the motion of the UGV, we propose to integrate a velocity of a laser range finder (LRF) into the scan matching optimization framework. Besides, to reduce the effect of dynamic objects such as walking pedestrians often existed in indoor scenes as much as possible, we propose a new occupancy likelihood map learning strategy by increasing or decreasing the probability of each occupancy grid after each scan matching. Experimental results in several challenged indoor scenes demonstrate that our proposed approach is capable of providing high-precision SLAM results.

Air-Sense: indoor environment monitoring evaluation system based on ZigBee network

Science.gov (United States)

Huang, Yang; Hu, Liang; Yang, Disheng; Liu, Hengchang

2017-08-01

In the modern life, people spend most of their time indoors. However, indoor environmental quality problems have always been affecting people’s social activities. In general, indoor environmental quality is also related to our indoor activities. Since most of the organic irritants and volatile gases are colorless, odorless and too tiny to be seen, because we have been unconsciously overlooked indoor environment quality. Consequently, our body suffer a great health problem. In this work, we propose Air-Sense system which utilizes the platform of ZigBee Network to collect and detect the real-time indoor environment quality. What’s more, Air-Sense system can also provide data analysis, and visualizing the results of the indoor environment to the user.

A large-scale RF-based Indoor Localization System Using Low-complexity Gaussian filter and improved Bayesian inference

Directory of Open Access Journals (Sweden)

L. Xiao

2013-04-01

Full Text Available The growing convergence among mobile computing device and smart sensors boosts the development of ubiquitous computing and smart spaces, where localization is an essential part to realize the big vision. The general localization methods based on GPS and cellular techniques are not suitable for tracking numerous small size and limited power objects in the indoor case. In this paper, we propose and demonstrate a new localization method, this method is an easy-setup and cost-effective indoor localization system based on off-the-shelf active RFID technology. Our system is not only compatible with the future smart spaces and ubiquitous computing systems, but also suitable for large-scale indoor localization. The use of low-complexity Gaussian Filter (GF, Wheel Graph Model (WGM and Probabilistic Localization Algorithm (PLA make the proposed algorithm robust and suitable for large-scale indoor positioning from uncertainty, self-adjective to varying indoor environment. Using MATLAB simulation, we study the system performances, especially the dependence on a number of system and environment parameters, and their statistical properties. The simulation results prove that our proposed system is an accurate and cost-effective candidate for indoor localization.

Occurrence, sources and human exposure assessment of SCCPs in indoor dust of northeast China.

Science.gov (United States)

Liu, Li-Hua; Ma, Wan-Li; Liu, Li-Yan; Huo, Chun-Yan; Li, Wen-Long; Gao, Chong-Jing; Li, Hai-Ling; Li, Yi-Fan; Chan, Hing Man

2017-06-01

Short-chain chlorinated paraffins (SCCPs) are widely used chemicals in household products and might cause adverse human health effects. However, limited information is available on the occurrence of SCCPs in indoor environments and their exposure risks on humans. In this study the concentrations, profiles and human exposure of SCCPs in indoor dust from five different indoor environments, including commercial stores, residential apartments, dormitories, offices and laboratories were characterized. The SCCPs levels ranged from 10.1 to 173.0 μg/g, with the median and mean concentration of 47.2 and 53.6 μg/g, respectively. No significant difference was found on concentrations among the five microenvironments. The most abundant compounds in indoor dust samples were homologues of C 13 group, Cl 7 group and N 20 (N is the total number of C and Cl) group. In the five microenvironments, commercial stores were more frequently exposed to shorter carbon chained and higher chlorinated homologues. Three potential sources for SCCPs were identified by the multiple linear regression of factor score model and correspondence analysis. The major sources of SCCPs in indoor dust were technical mixtures of CP-42 (42% chlorine, w/w) and CP-52 b (52% chlorine, w/w). The total daily exposure doses and hazard quotients (HQ) were calculated by the human exposure models, and they were all below the reference doses and threshold values, respectively. Monte Carlo simulation was applied to predict the human exposure risk of SCCPs. Infants and toddlers were at risk of SCCPs based on predicted HQ values, which were exceeded the threshold for neoplastic effects in the worst case. Our results on the occurrences, sources and human exposures of SCCPs will be useful to provide a better understanding of SCCPs behaviors in indoor environment in China, and to support environmental risk evaluation and regulation of SCCPs in the world. Copyright © 2017. Published by Elsevier Ltd.

A prediction model for assessing residential radon concentration in Switzerland

International Nuclear Information System (INIS)

Hauri, Dimitri D.; Huss, Anke; Zimmermann, Frank; Kuehni, Claudia E.; Röösli, Martin

2012-01-01

Indoor radon is regularly measured in Switzerland. However, a nationwide model to predict residential radon levels has not been developed. The aim of this study was to develop a prediction model to assess indoor radon concentrations in Switzerland. The model was based on 44,631 measurements from the nationwide Swiss radon database collected between 1994 and 2004. Of these, 80% randomly selected measurements were used for model development and the remaining 20% for an independent model validation. A multivariable log-linear regression model was fitted and relevant predictors selected according to evidence from the literature, the adjusted R², the Akaike's information criterion (AIC), and the Bayesian information criterion (BIC). The prediction model was evaluated by calculating Spearman rank correlation between measured and predicted values. Additionally, the predicted values were categorised into three categories (50th, 50th–90th and 90th percentile) and compared with measured categories using a weighted Kappa statistic. The most relevant predictors for indoor radon levels were tectonic units and year of construction of the building, followed by soil texture, degree of urbanisation, floor of the building where the measurement was taken and housing type (P-values <0.001 for all). Mean predicted radon values (geometric mean) were 66 Bq/m³ (interquartile range 40–111 Bq/m³) in the lowest exposure category, 126 Bq/m³ (69–215 Bq/m³) in the medium category, and 219 Bq/m³ (108–427 Bq/m³) in the highest category. Spearman correlation between predictions and measurements was 0.45 (95%-CI: 0.44; 0.46) for the development dataset and 0.44 (95%-CI: 0.42; 0.46) for the validation dataset. Kappa coefficients were 0.31 for the development and 0.30 for the validation dataset, respectively. The model explained 20% overall variability (adjusted R²). In conclusion, this residential radon prediction model, based on a large number of measurements, was demonstrated to be

iParking: an intelligent indoor location-based smartphone parking service.

Science.gov (United States)

Liu, Jingbin; Chen, Ruizhi; Chen, Yuwei; Pei, Ling; Chen, Liang

2012-10-31

Indoor positioning technologies have been widely studied with a number of solutions being proposed, yet substantial applications and services are still fairly primitive. Taking advantage of the emerging concept of the connected car, the popularity of smartphones and mobile Internet, and precise indoor locations, this study presents the development of a novel intelligent parking service called iParking. With the iParking service, multiple parties such as users, parking facilities and service providers are connected through Internet in a distributed architecture. The client software is a light-weight application running on a smartphone, and it works essentially based on a precise indoor positioning solution, which fuses Wireless Local Area Network (WLAN) signals and the measurements of the built-in sensors of the smartphones. The positioning accuracy, availability and reliability of the proposed positioning solution are adequate for facilitating the novel parking service. An iParking prototype has been developed and demonstrated in a real parking environment at a shopping mall. The demonstration showed how the iParking service could improve the parking experience and increase the efficiency of parking facilities. The iParking is a novel service in terms of cost- and energy-efficient solution.

iParking: An Intelligent Indoor Location-Based Smartphone Parking Service

Directory of Open Access Journals (Sweden)

Liang Chen

2012-10-01

Full Text Available Indoor positioning technologies have been widely studied with a number of solutions being proposed, yet substantial applications and services are still fairly primitive. Taking advantage of the emerging concept of the connected car, the popularity of smartphones and mobile Internet, and precise indoor locations, this study presents the development of a novel intelligent parking service called iParking. With the iParking service, multiple parties such as users, parking facilities and service providers are connected through Internet in a distributed architecture. The client software is a light-weight application running on a smartphone, and it works essentially based on a precise indoor positioning solution, which fuses Wireless Local Area Network (WLAN signals and the measurements of the built-in sensors of the smartphones. The positioning accuracy, availability and reliability of the proposed positioning solution are adequate for facilitating the novel parking service. An iParking prototype has been developed and demonstrated in a real parking environment at a shopping mall. The demonstration showed how the iParking service could improve the parking experience and increase the efficiency of parking facilities. The iParking is a novel service in terms of cost- and energy-efficient solution.

iParking: An Intelligent Indoor Location-Based Smartphone Parking Service

Science.gov (United States)

Liu, Jingbin; Chen, Ruizhi; Chen, Yuwei; Pei, Ling; Chen, Liang

2012-01-01

Indoor positioning technologies have been widely studied with a number of solutions being proposed, yet substantial applications and services are still fairly primitive. Taking advantage of the emerging concept of the connected car, the popularity of smartphones and mobile Internet, and precise indoor locations, this study presents the development of a novel intelligent parking service called iParking. With the iParking service, multiple parties such as users, parking facilities and service providers are connected through Internet in a distributed architecture. The client software is a light-weight application running on a smartphone, and it works essentially based on a precise indoor positioning solution, which fuses Wireless Local Area Network (WLAN) signals and the measurements of the built-in sensors of the smartphones. The positioning accuracy, availability and reliability of the proposed positioning solution are adequate for facilitating the novel parking service. An iParking prototype has been developed and demonstrated in a real parking environment at a shopping mall. The demonstration showed how the iParking service could improve the parking experience and increase the efficiency of parking facilities. The iParking is a novel service in terms of cost- and energy-efficient solution. PMID:23202179

Indoor climate design for a monumental building with periodic high indoor moisture loads

NARCIS (Netherlands)

Schijndel, van A.W.M.; Lony, R.J.M.; Schellen, H.L.

2008-01-01

The paper presents a case study on the performance based design for the indoor climate of a monumental building with periodic high indoor moisture loads. Several scenarios of the past performance and new control classes are simulated and evaluated. The results include the influence of hygric inertia

Resident’s Floor Level Preference in High-Rise Residential Buildings in China:A Case Study of Shijiazhuang City,Hebei Province

Institute of Scientific and Technical Information of China (English)

Sun; Pingjun; Wang; Ying; Pang; Ruiqiu; Song; Xinyan

2016-01-01

With the constant advance of global urbanization and aggravation of urban construction land scarcity,high-rise residential buildings have become one of the main carriers of urban residential function on account of both land saving and large housing requirement.However,relevant studies on consumers’ floor selection preference in high-rise residential buildings,regarding what inherent and regular features and causes it has,are still insufficient,despite that related issues have important practical significance for real estate developers and designers’ decision making in terms of dwelling size ratio,floor area,indoor layout,and so on.This study,based on systematic examination of existing domestic and international researches,seeks to make empirical tests and generalization on the above issues from the aspect of "utility function"(safety,comfortableness,accessibility and economic efficiency) of the living environment that impacted by different floor levels,and floor selection features regarding consumers’ social and family structure attributes,as well as the intrinsic correlation between them.The results show the existence of floor level preference in high-rise residential buildings.Its essence is a personalized characterization of consumers’ social and family structures’ attributes in selecting the "utility function" of the living environment,as the preference value differs under various attributes including gender,age,income,family members and others.

Computer program for sizing residential energy recovery ventilator

International Nuclear Information System (INIS)

Koontz, M.D.; Lee, S.M.; Spears, J.W.; Kesselring, J.P.

1991-01-01

Energy recovery ventilators offer the prospect of tighter control over residential ventilation rates than manual methods, such as opening windows, with a lesser energy penalty. However, the appropriate size of such a ventilator is not readily apparent in most situations. Sizing of energy recovery ventilation software was developed to calculate the size of ventilator necessary to satisfy ASHRAE Standard 62-1989, Ventilation for Acceptable Air Quality, or a user-specified air exchange rate. Inputs to the software include house location, structural characteristics, house operations and energy costs, ventilation characteristics, and HVAC system COP/efficiency. Based on these inputs, the program estimates the existing air exchange rate for the house, the ventilation rate required to meet the ASHRAE standard or user-specified air exchange rate, the size of the ventilator needed to meet the requirement, and the expected changes in indoor air quality and energy consumption. In this paper an illustrative application of the software is provided

Design of indoor temperature and humidity detection system based on single chip microcomputer

Science.gov (United States)

Fu, Xiuwei; Fu, Li; Ma, Tianhui

2018-03-01

The indoor temperature and humidity detection system based on STC15F2K60S2 is designed in this paper. The temperature and humidity sensor DHT22 to monitor the indoor temperature and humidity are used, and the temperature and humidity data to the user's handheld device are wirelessly transmitted, when the temperature reaches or exceeds the user set the temperature alarm value, and the system sound and light alarm, to remind the user.

Indoor 3D Route Modeling Based On Estate Spatial Data

Science.gov (United States)

Zhang, H.; Wen, Y.; Jiang, J.; Huang, W.

2014-04-01

Indoor three-dimensional route model is essential for space intelligence navigation and emergency evacuation. This paper is motivated by the need of constructing indoor route model automatically and as far as possible. By comparing existing building data sources, this paper firstly explained the reason why the estate spatial management data is chosen as the data source. Then, an applicable method of construction three-dimensional route model in a building is introduced by establishing the mapping relationship between geographic entities and their topological expression. This data model is a weighted graph consist of "node" and "path" to express the spatial relationship and topological structure of a building components. The whole process of modelling internal space of a building is addressed by two key steps: (1) each single floor route model is constructed, including path extraction of corridor using Delaunay triangulation algorithm with constrained edge, fusion of room nodes into the path; (2) the single floor route model is connected with stairs and elevators and the multi-floor route model is eventually generated. In order to validate the method in this paper, a shopping mall called "Longjiang New City Plaza" in Nanjing is chosen as a case of study. And the whole building space is constructed according to the modelling method above. By integrating of existing path finding algorithm, the usability of this modelling method is verified, which shows the indoor three-dimensional route modelling method based on estate spatial data in this paper can support indoor route planning and evacuation route design very well.

Toxicity and elemental composition of particulate matter from outdoor and indoor air of elementary schools in Munich, Germany.

Science.gov (United States)

Oeder, S; Dietrich, S; Weichenmeier, I; Schober, W; Pusch, G; Jörres, R A; Schierl, R; Nowak, D; Fromme, H; Behrendt, H; Buters, J T M

2012-04-01

Outdoor particulate matter (PM(10)) is associated with detrimental health effects. However, individual PM(10) exposure occurs mostly indoors. We therefore compared the toxic effects of classroom, outdoor, and residential PM(10). Indoor and outdoor PM(10) was collected from six schools in Munich during teaching hours and in six homes. Particles were analyzed by scanning electron microscopy and X-ray spectroscopy (EDX). Toxicity was evaluated in human primary keratinocytes, lung epithelial cells and after metabolic activation by several human cytochromes P450. We found that PM(10) concentrations during teaching hours were 5.6-times higher than outdoors (117 ± 48 μg/m(3) vs. 21 ± 15 μg/m(3), P particle number), organic (29%, probably originating from human skin), and Ca-carbonate particles (12%, probably originating from paper). Outdoor PM contained more Ca-sulfate particles (38%). Indoor PM at 6 μg/cm(2) (10 μg/ml) caused toxicity in keratinocytes and in cells expressing CYP2B6 and CYP3A4. Toxicity by CYP2B6 was abolished with the reactive oxygen species scavenger N-acetylcysteine. We concluded that outdoor PM(10) and indoor PM(10) from homes were devoid of toxicity. Indoor PM(10) was elevated, chemically different and toxicologically more active than outdoor PM(10). Whether the effects translate into a significant health risk needs to be determined. Until then, we suggest better ventilation as a sensible option. Indoor air PM(10) on an equal weight base is toxicologically more active than outdoor PM(10). In addition, indoor PM(10) concentrations are about six times higher than outdoor air. Thus, ventilation of classrooms with outdoor air will improve air quality and is likely to provide a health benefit. It is also easier than cleaning PM(10) from indoor air, which has proven to be tedious. © 2011 John Wiley & Sons A/S.

Locating room air-conditioners at floor level for energy saving in residential buildings

International Nuclear Information System (INIS)

Gao, C.F.; Lee, W.L.; Chen Hua

2009-01-01

Residential air-conditioning becomes a common feature in our daily life. They are typically installed at high level known as ceiling-based system (CAC). With the increasing use of floor-based air-conditioning system in commercial buildings for energy saving, it is proposed in this study to locate a top discharge/front return air-conditioner at floor level to resemble a floor-based air-conditioning system (FAC) to curb energy use in residential buildings. Given the concerns about draught discomfort and thermal stratification associated with floor-based air-conditioning systems, the objective of this study is to evaluate the air distribution performance and to quantify the possible energy benefits. Bedroom was chosen as a sensitive case for detailed air distribution performance evaluation. Experimental study, CFD simulations and energy simulations were conducted in achieving the specific objectives. CAC and FAC were installed in a bedroom-like environmental chamber for experimental study at different indoor and outdoor conditions. The air velocities and temperatures at various positions and levels inside the chamber were measured to determine the air distribution performance indices (ADPI) and airflow draft risk (DR). The cooling output, power consumption and coefficient of performance (COP) of the two units were measured and calculated for comparison. The experimental results show that ADPI of CAC and FAC are 92.3% and 84.6%, respectively. COP of FAC is 8.11% higher than CAC, and the corresponding DR are comparable. The experimental results were used to validate the CFD simulations as well as providing actual performance data for predicting the energy use of applying CAC and FAC in a case-study building. CFD simulations and draught assessment confirmed that there is no potential draught discomfort and thermal stratification associated with the use of FAC. Energy simulations predicted that the associated energy saving is 6.9%. Wider use of FAC in residential

Shelter planning based on self-saving concepts in urban residential districts

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Buri Qi

2017-01-01

Full Text Available With increasing population density in Asia, the potential higher risk was resulted from the residential districts with the higher plot ratio, especially in some megapolis (eg. Beijing and Shanghai. Presently it is more difficult for the rescue operation during the disasters because of the decreasing safe space among the buildings as a result of higher buildings and denser the district. Thus, an immediate self-saving action is more important than before during the disaster in the residential districts, and its realization depends on the reasonable shelter planning and its management system. In this study, the factors related to the self-saving were analyzed and concluded by the related the literatures retrieval and case study, and the case study was done by the in-depth interview and questionnaires in three different residential districts in Shanghai. It was found that the following factors related to the self-saving should be considered in the shelters planning: the distribution of the shelters including their space accessibility and area, evacuation passageways, the facilities of the disaster prevention (such as fire hydrant and guide signs and subsidiary facilities (such as vegetation for the disaster prevention, the social cohesion, awareness of the self-saving and disaster prevention. Simultaneously, the shelters planning countermeasures based on the self-saving were proposed, which provided some theoretical bases for the study  and plan of the security residential districts in future.

INDOOR SUBSPACING TO IMPLEMENT INDOORGML FOR INDOOR NAVIGATION

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H. Jung

2015-10-01

Full Text Available According to an increasing demand for indoor navigation, there are great attempts to develop applicable indoor network. Representation for a room as a node is not sufficient to apply complex and large buildings. As OGC established IndoorGML, subspacing to partition the space for constructing logical network is introduced. Concerning subspacing for indoor network, transition space like halls or corridors also have to be considered. This study presents the subspacing process for creating an indoor network in shopping mall. Furthermore, categorization of transition space is performed and subspacing of this space is considered. Hall and squares in mall is especially defined for subspacing. Finally, implementation of subspacing process for indoor network is presented.

Indoor Subspacing to Implement Indoorgml for Indoor Navigation

Science.gov (United States)

Jung, H.; Lee, J.

2015-10-01

According to an increasing demand for indoor navigation, there are great attempts to develop applicable indoor network. Representation for a room as a node is not sufficient to apply complex and large buildings. As OGC established IndoorGML, subspacing to partition the space for constructing logical network is introduced. Concerning subspacing for indoor network, transition space like halls or corridors also have to be considered. This study presents the subspacing process for creating an indoor network in shopping mall. Furthermore, categorization of transition space is performed and subspacing of this space is considered. Hall and squares in mall is especially defined for subspacing. Finally, implementation of subspacing process for indoor network is presented.

Indoor, outdoor, and personal exposure monitoring of particulate air pollution: the Baltimore elderly epidemiology-exposure pilot study

Science.gov (United States)

Williams, Ron; Creason, John; Zweidinger, Roy; Watts, Randall; Sheldon, Linda; Shy, Carl

A 17-day pilot study investigating potential PM exposures of an elderly population was conducted near Baltimore, Maryland. Collection of residential indoor, residential outdoor, and ambient monitoring data associated with the subjects living at a common retirement facility was integrated with results from a paired epidemiological pilot study. This integration was used to investigate the potential pathophysiological health effects resulting from daily changes in estimated PM exposures with results reported elsewhere. Objectives of the exposure study were to determine the feasibility of performing PM exposure assessment upon an elderly population and establishing relationships between the various exposure measures including personal monitoring. PM 2.5 was determined to be the dominant outdoor size fraction (0.83 PM 2.5/PM 10 mass ratio by dichot monitoring). Individual 24-h PM 1.5 personal exposures ranged from 12 to 58 μg m -3. Comparison of data from matched sampling dates resulted in mean daily PM 1.5 personal, PM 2.5 outdoor, and PM 1.5 indoor concentrations of 34, 17, and 17 μg m -3, respectively. Activity patterns of the study population indicated a generally sedentary population spending a mean of 96% of each day indoors. Future studies would benefit from the use of a consistent sampling methodology across a larger number of PM measurement sites relevant to the elderly subjects, as well as a larger personal PM exposure study population to more successfully collect data needed in matched epidemiological-exposure studies.

Effects of Heterogeneity in Residential Preferences on an Agent-Based Model of Urban Sprawl

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Daniel G. Brown

2006-06-01

Full Text Available The ability of agent-based models (ABMs to represent heterogeneity in the characteristics and behaviors of actors enables analyses about the implications of this heterogeneity for system behavior. The importance of heterogeneity in the specification of ABMs, however, creates new demands for empirical support. An earlier analysis of a survey of residential preferences within southeastern Michigan revealed seven groups of residents with similar preferences on similar characteristics of location. In this paper, we present an ABM that represents the process of residential development within an urban system and run it for a hypothetical pattern of environmental variation. Residential locations are selected by residential agents, who evaluate locations on the basis of preference for nearness to urban services, including jobs, aesthetic quality of the landscape, and their similarity to their neighbors. We populate our ABM with a population of residential preferences drawn from the survey results in five different ways: (1 preferences drawn at random; (2 equal preferences based on the mean from the entire survey sample; (3 preferences drawn from a single distribution, whose mean and standard deviation are derived from the survey sample; (4 equal preferences within each of seven groups, based on the group means; and (5 preferences drawn from distributions for each of seven groups, defined by group means and standard deviations. Model sensitivity analysis, based on multiple runs of our model under each case, revealed that adding heterogeneity to agents has a significant effect on model outcomes, measured by aggregate patterns of development sprawl and clustering.

Differential barometric-based positioning technique for indoor elevation measurement in IoT medical applications.

Science.gov (United States)

Wang, Hua; Wen, Yingyou; Zhao, Dazhe

2017-07-20

Medical applications have begun to benefit from Internet of Things (IoT) technology through the introduction of wearable devices. Several medical applications require accurate patient location as various changes affect pressure parameters inside the body. This study aims to develop a system to measure indoor altitude for IoT medical applications. We propose a differential barometric-based positioning system to estimate the altitude between a reference sensor and a localizing sensor connected to the human body. The differential barometric altimetry model is introduced to estimate indoor elevations and eliminate environmental artifacts. In addition, a Gaussian filter processing is adopted to remove noise from the elevation measurements. The proposed system is then investigated through extensive experiments, using various evaluation criteria. The results indicate that the proposed system yielded good accuracy with reduced implementation complexity and fewer costs. The proposed system is resilient compared to other indoor localization approaches, even when numerous environmental artifacts in indoor environments are present.

[Level of microwave radiation from mobile phone base stations built in residential districts].

Science.gov (United States)

Hu, Ji; Lu, Yiyang; Zhang, Huacheng; Xie, Hebing; Yang, Xinwen

2009-11-01

To investigate the condition of microwave radiation pollution from mobile phone base station built in populated area. Random selected 18 residential districts where had base station and 10 residential districts where had no base stations. A TES-92 electromagnetic radiation monitor were used to measure the intensity of microwave radiation in external and internal living environment. The intensities of microwave radiation in the exposure residential districts were more higher than those of the control residential districts (p station, it would gradually weaken with the increase of the distance. The level of microwave radiation in antenna main lobe region is not certainly more higher than the side lobe direction, and the side lobe direction also is not more lower. At the same district, where there were two base stations, the electromagnetic field nestification would take place in someplace. The intensities of microwave radiation outside the exposure windows in the resident room not only changed with distance but also with the height of the floor. The intensities of microwave radiation inside the aluminum alloys security net were more lower than those of outside the aluminum alloys security net (p 0.05). Although all the measure dates on the ground around the base station could be below the primary standard in "environment electromagnetic wave hygienic standard" (GB9175-88), there were still a minorities of windows which exposed to the base station were higher, and the outside or inside of a few window was even higher beyond the primary safe level defined standard. The aluminum alloys security net can partly shield the microwave radiation from the mobile phone base station.

Geologic influence on indoor radon concentrations and gamma radiation levels in Norwegian dwellings

Energy Technology Data Exchange (ETDEWEB)

Sundal, Aud Venche

2003-09-01

Indoor radon levels in 1618 Norwegian dwellings located in different geological settings were compared with geological information in order to determine potential correlations between geological factors and indoor radon concentrations in Norway and to establish whether geological information is useful in radon risk analysis. In two geographically limited areas, Kinsarvik and Fen, detailed geological and geochemical investigations were carried out in order to explain their elevated natural radiation environment. Significant correlations between geology and indoor radon concentrations in Norway are found when the properties of both the bedrock and the overburden are taken into account. Areas of high radon risk in Norway include 1) exposed bedrock with elevated levels of radium (mainly alum shale and granites) and b) highly permeable unconsolidated sediments derived from all rock types (mainly glaciofluvial and fluvial deposits) and moderately permeable sediments containing radium rich rock fragments (mainly basal till). More than 20 % of Norwegian dwellings located in the high-risk areas can be expected to contain radon levels exceeding 200 Bq/m3. The elevated radon risk related to penneable building grounds is illustrated in Kinsarvik where the highly permeable sediments and the large vadose zone underlying the Huse residential area enable the transport of radon from large volumes into the dwellings resulting in enhanced indoor radon concentrations. Subterranean air flows caused by temperature/pressure differences between soil air and atmospheric air and elevations differences within the Huse area are shown to strongly affect the annual variations in indoor radon concentrations. The marked contrasts in radon risk potential between different types of building grounds are clearly illustrated in the Fen area where outcrops of the radium rich Fen carbonatites represent areas of high radon risk while only low levels of both indoor radon concentrations and indoor gamma

Probabilistic estimation of residential air exchange rates for ...

Science.gov (United States)

Residential air exchange rates (AERs) are a key determinant in the infiltration of ambient air pollution indoors. Population-based human exposure models using probabilistic approaches to estimate personal exposure to air pollutants have relied on input distributions from AER measurements. An algorithm for probabilistically estimating AER was developed based on the Lawrence Berkley National Laboratory Infiltration model utilizing housing characteristics and meteorological data with adjustment for window opening behavior. The algorithm was evaluated by comparing modeled and measured AERs in four US cities (Los Angeles, CA; Detroit, MI; Elizabeth, NJ; and Houston, TX) inputting study-specific data. The impact on the modeled AER of using publically available housing data representative of the region for each city was also assessed. Finally, modeled AER based on region-specific inputs was compared with those estimated using literature-based distributions. While modeled AERs were similar in magnitude to the measured AER they were consistently lower for all cities except Houston. AERs estimated using region-specific inputs were lower than those using study-specific inputs due to differences in window opening probabilities. The algorithm produced more spatially and temporally variable AERs compared with literature-based distributions reflecting within- and between-city differences, helping reduce error in estimates of air pollutant exposure. Published in the Journal of

Measurement-Based Spatial Correlation and Capacity of Indoor Distributed MIMO System

Directory of Open Access Journals (Sweden)

Yan Zhang

2013-01-01

Full Text Available Distributed MIMO (D-MIMO system is one of the candidates for future wireless access networks. In this study, the spatial correlation and capacity in indoor D-MIMO system are presented. All results are from the actual channel measurements in typical indoor scenarios, including office and corridor. Based on measured data, spatial correlation coefficients between distributed transmitting antennas are analyzed. Although the literature about D-MIMO system assumes the small scale fading between distributed antennas is independent, we find that spatial correlation may still exist in specific propagation scenario. This correlation can also degrade the performance of D-MIMO system. To mitigate the impact of spatial correlation, one efficient method is to use transmitting antenna selection technique.

Specification of indoor climate design parameters at the assessment of moisture protective properties of enclosing structures

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Kornienko Sergey Valer’evich

2016-11-01

Full Text Available Due to wide implementation of enveloping structures with increased heat-insulation properties in modern construction here appeared a necessity to assess their moisture conditions. Assessment of moisture conditions of enveloping structures is carried out according to maximum allowable moisture state basing on determining the surface of maximum damping. In relation to it the necessity of additional vapour barrier is checked using moisture balance equation. Though the change of indoor climate parameters in premises is not taken into account in moisture balance equations defined for different seasons. The author improves the method of calculating moisture protective parameters of enclosing structures according to the maximum allowable damping state for a year and a period of moisture accumulation. It is shown in this article that accounting of temperature and relative humidity change of inside air allows specifying calculated parameters of indoor climate in residential and office rooms in assessment of moisture protective properties of enclosing structures for the case of an effective enclosing structure with a façade heat-insulation composite system. Coordinates of the maximum moistened surface of the envelope depends on indoor climate design parameters. It is concluded that the increase of requirements for moisture protection of enclosing structures when using design values of temperature and relative humidity of internal air according to the Russian regulation (SP 50.13330.2012 is not always reasonable. Accounting of changes of indoor climate parameters allows more precise assessment of moisture protective properties of enclosing structures during their design.

Oxygen fugacity and piston cylinder capsule assemblies

Science.gov (United States)

Jakobsson, S.

2011-12-01

A double capsule assembly designed to control oxygen fugacity in piston cylinder experiments has been tested at 1200 °C and 10 kbar. The assembly consists of an outer Pt-capsule containing a solid buffer (Ni-NiO or Co-CoO plus H2O) and an inner AuPd-capsule containing the sample, H2O and a Pt-wire. To prevent direct contact with the buffer phases the AuPd-capsule is embedded in finely ground Al2O3 along with some coarser, fractured Al2O3 facilitating fluid inclusion formation. No water loss is observed in the sample even after 48 hrs but a slight increase in water content is observed in longer duration runs due to oxygen and hydrogen diffusion into the AuPd-capsule. Carbon from the furnace also diffuses through the outer Pt-capsule but reacts with H2O in the outer capsule to form CO2 and never reaches the inner capsule. Oxygen fugacity of runs in equilibrium with the Ni-NiO and Co-CoO buffers was measured by analyzing the Fe content of the Pt-wire in the sample1 and by analyzing Fe dissolved in the AuPd capsule2. The second method gives values that are in good agreement with established buffer whereas results from the first method are one half to one log units higher than the established values. References 1. E. Medard, C. A. McCammon, J. A. Barr, T. L. Grove, Am. Mineral. 93, 1838 (2008). 2. J. Barr, T. Grove, Contrib. Mineral. Petrol. 160, 631 (2010)

Graph-Based Semi-Supervised Learning for Indoor Localization Using Crowdsourced Data

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Liye Zhang

2017-04-01

Full Text Available Indoor positioning based on the received signal strength (RSS of the WiFi signal has become the most popular solution for indoor localization. In order to realize the rapid deployment of indoor localization systems, solutions based on crowdsourcing have been proposed. However, compared to conventional methods, lots of different devices are used in crowdsourcing system and less RSS values are collected by each device. Therefore, the crowdsourced RSS values are more erroneous and can result in significant localization errors. In order to eliminate the signal strength variations across diverse devices, the Linear Regression (LR algorithm is proposed to solve the device diversity problem in crowdsourcing system. After obtaining the uniform RSS values, a graph-based semi-supervised learning (G-SSL method is used to exploit the correlation between the RSS values at nearby locations to estimate an optimal RSS value at each location. As a result, the negative effect of the erroneous measurements could be mitigated. Since the AP locations need to be known in G-SSL algorithm, the Compressed Sensing (CS method is applied to precisely estimate the location of the APs. Based on the location of the APs and a simple signal propagation model, the RSS difference between different locations is calculated and used as an additional constraint to improve the performance of G-SSL. Furthermore, to exploit the sparsity of the weights used in the G-SSL, we use the CS method to reconstruct these weights more accurately and make a further improvement on the performance of the G-SSL. Experimental results show improved results in terms of the smoothness of the radio map and the localization accuracy.

A Single LiDAR-Based Feature Fusion Indoor Localization Algorithm.

Science.gov (United States)

Wang, Yun-Ting; Peng, Chao-Chung; Ravankar, Ankit A; Ravankar, Abhijeet

2018-04-23

In past years, there has been significant progress in the field of indoor robot localization. To precisely recover the position, the robots usually relies on multiple on-board sensors. Nevertheless, this affects the overall system cost and increases computation. In this research work, we considered a light detection and ranging (LiDAR) device as the only sensor for detecting surroundings and propose an efficient indoor localization algorithm. To attenuate the computation effort and preserve localization robustness, a weighted parallel iterative closed point (WP-ICP) with interpolation is presented. As compared to the traditional ICP, the point cloud is first processed to extract corners and line features before applying point registration. Later, points labeled as corners are only matched with the corner candidates. Similarly, points labeled as lines are only matched with the lines candidates. Moreover, their ICP confidence levels are also fused in the algorithm, which make the pose estimation less sensitive to environment uncertainties. The proposed WP-ICP architecture reduces the probability of mismatch and thereby reduces the ICP iterations. Finally, based on given well-constructed indoor layouts, experiment comparisons are carried out under both clean and perturbed environments. It is shown that the proposed method is effective in significantly reducing computation effort and is simultaneously able to preserve localization precision.

A Single LiDAR-Based Feature Fusion Indoor Localization Algorithm

Directory of Open Access Journals (Sweden)

Yun-Ting Wang

2018-04-01

Full Text Available In past years, there has been significant progress in the field of indoor robot localization. To precisely recover the position, the robots usually relies on multiple on-board sensors. Nevertheless, this affects the overall system cost and increases computation. In this research work, we considered a light detection and ranging (LiDAR device as the only sensor for detecting surroundings and propose an efficient indoor localization algorithm. To attenuate the computation effort and preserve localization robustness, a weighted parallel iterative closed point (WP-ICP with interpolation is presented. As compared to the traditional ICP, the point cloud is first processed to extract corners and line features before applying point registration. Later, points labeled as corners are only matched with the corner candidates. Similarly, points labeled as lines are only matched with the lines candidates. Moreover, their ICP confidence levels are also fused in the algorithm, which make the pose estimation less sensitive to environment uncertainties. The proposed WP-ICP architecture reduces the probability of mismatch and thereby reduces the ICP iterations. Finally, based on given well-constructed indoor layouts, experiment comparisons are carried out under both clean and perturbed environments. It is shown that the proposed method is effective in significantly reducing computation effort and is simultaneously able to preserve localization precision.

Capturing Hotspots For Constrained Indoor Movement

DEFF Research Database (Denmark)

Ahmed, Tanvir; Pedersen, Torben Bach; Lu, Hua

2013-01-01

Finding the hotspots in large indoor spaces is very important for getting overloaded locations, security, crowd management, indoor navigation and guidance. The tracking data coming from indoor tracking are huge in volume and not readily available for finding hotspots. This paper presents a graph......-based model for constrained indoor movement that can map the tracking records into mapping records which represent the entry and exit times of an object in a particular location. Then it discusses the hotspots extraction technique from the mapping records....

A Dynamic Optimization Method of Indoor Fire Evacuation Route Based on Real-time Situation Awareness

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DING Yulin

2016-12-01

Full Text Available How to provide safe and effective evacuation routes is an important safeguard to correctly guide evacuation and reduce the casualties during the fire situation rapidly evolving in complex indoor environment. The traditional static path finding method is difficult to adjust the path adaptively according to the changing fire situation, which lead to the evacuation decision-making blindness and hysteresis. This paper proposes a dynamic method which can dynamically optimize the indoor evacuation routes based on the real-time situation awareness. According to the real-time perception of fire situation parameters and the changing indoor environment information, the evacuation route is optimized dynamically. The integrated representation of multisource indoor fire monitoring sensor observations oriented fire emergency evacuation is presented at first, real-time fire threat situation information inside building is then extracted from the observation data of multi-source sensors, which is used to constrain the dynamical optimization of the topology of the evacuation route. Finally, the simulation experiments prove that this method can improve the accuracy and efficiency of indoor evacuation routing.

The effect of proximity to major roads on indoor air quality in typical Australian dwellings

Science.gov (United States)

Lawson, Sarah J.; Galbally, Ian E.; Powell, Jennifer C.; Keywood, Melita D.; Molloy, Suzie B.; Cheng, Min; Selleck, Paul W.

2011-04-01

An Indoor Air Quality Study of residential dwellings was carried out in Melbourne, Australia, and a subset of the data was analysed to investigate the effect of proximity to major roads on indoor air quality (IAQ). Seven-day measurements of PM 10, NO 2, benzene, toluene, ethylbenzene and xylenes, along with continuous CO and PM 2.5 measurements were utilised. The measurements were made indoors and outdoors in 27 dwellings; 15 Near Road (300 m from a major road). Dwellings were sampled for one week each in Winter/Spring 2008 and Summer/Autumn 2009, over an eight month period. Analysis of 7-day measurements showed that NO 2 and toluene were elevated at the 5% significance level both indoors and outdoors at Near Road Dwellings compared to Far Road Dwellings. Indoor/Outdoor (I/O) ratios of NO 2 and toluene were not significantly different between Near and Far Road dwellings giving no evidence of any anomalous dominant indoor source for NO 2 and toluene in Near Road dwellings. Indoor NO 2 was significantly correlated to gas stovetop and oven use in both Near and Far Road dwellings. In the absence of gas cooking, indoor NO 2 was elevated in Near Road dwellings relative to Far Road dwellings by approximately 4 ppb and this can be attributed to infiltration of outdoor air. I/O ratios for NO 2 were 2 indicating that indoor sources dominate with minor contribution from outdoors. Hence the relative contribution of roadways to indoor NO 2 is potentially greater than the relative contribution of roadways to indoor toluene. Findings elsewhere suggest that a similar outdoor enhancement of traffic related NO 2 (˜5 ppb) increases risk of lung cancer and childhood asthma ( Brauer et al., 2000; Nyberg et al., 2000). A simple conceptual model indicated spatial and temporal variance in the concentrations was the biggest limitation in detecting roadway influence outside Near Road dwellings for PM 10, PM 2.5 and NO 2 while measurement uncertainty was also important for CO.

VOLTTRON-Based System for Providing Ancillary Services with Residential Building Loads

Energy Technology Data Exchange (ETDEWEB)

Jin, Xin

2016-07-01

Ancillary services entail controlled modulation of building equipment to maintain a stable balance of generation and load in the power system. Ancillary services include frequency regulation and contingency reserves, whose acting time ranges from several seconds to several minutes. Many pilot studies have been implemented to use industrial loads to provide ancillary services, and some have explored services from commercial building loads or electric vehicle charging loads. Residential loads, such as space conditioning and water heating, represent a largely untapped resource for providing ancillary services. The residential building sector accounts for a significant fraction of the total electricity use in the United States. Many loads in residential buildings are flexible and could potentially be curtailed or shifted at the request of the grid. However, there are many barriers that prevent residential loads being widely used for ancillary services. One of the major technical barriers is the lack of communication capabilities between end-use devices and the grid. End-use devices need to be able to receive the automatic generation control (AGC) signal from the grid operator and supply certain types of telemetry to verify response. With the advance of consumer electronics, communication-enabled, or 'connected,' residential equipment has emerged to overcome the communication barrier. However, these end-use devices have introduced a new interoperability challenge due to the existence of numerous standards and communication protocols among different end devices. In this paper, we present a VOLTTRON-based system that overcomes these technical challenges and provides ancillary services with residential loads. VOLTTRON is an open-source control and sensing platform for building energy management, facilitating interoperability solutions for end devices. We have developed drivers to communicate and control different types of end devices through standard-based

Seamless Indoor/Outdoor Positioning Handover for Location-Based Services in Streamspin

DEFF Research Database (Denmark)

Hansen, Rene; Wind, Rico; Jensen, Christian Søndergaard

2009-01-01

the delivery of truly ubiquitous location-based services by integrating GPS and Wi-Fi location fingerprinting. The paper puts focus on key aspects of the seamless handover between outdoor to indoor positioning. Several different handover solutions are presented,and their applicability is evaluated with respect...

Indoor Radon Concentration Related to Different Radon Areas and Indoor Radon Prediction

Science.gov (United States)

Juhásová Šenitková, Ingrid; Šál, Jiří

2017-12-01

Indoor radon has been observed in the buildings at areas with different radon risk potential. Preventive measures are based on control of main potential radon sources (soil gas, building material and supplied water) to avoid building of new houses above recommended indoor radon level 200 Bq/m3. Radon risk (index) estimation of individual building site bedrock in case of new house siting and building protection according technical building code are obligatory. Remedial actions in buildings built at high radon risk areas were carried out principally by unforced ventilation and anti-radon insulation. Significant differences were found in the level of radon concentration between rooms where radon reduction techniques were designed and those where it was not designed. The mathematical model based on radon exhalation from soil has been developed to describe the physical processes determining indoor radon concentration. The model is focused on combined radon diffusion through the slab and advection through the gap from sub-slab soil. In this model, radon emanated from building materials is considered not having a significant contribution to indoor radon concentration. Dimensional analysis and Gauss-Newton nonlinear least squares parametric regression were used to simplify the problem, identify essential input variables and find parameter values. The presented verification case study is introduced for real buildings with respect to various underground construction types. Presented paper gives picture of possible mathematical approach to indoor radon concentration prediction.

Home interventions are effective at decreasing indoor nitrogen dioxide concentrations.

Science.gov (United States)

Paulin, L M; Diette, G B; Scott, M; McCormack, M C; Matsui, E C; Curtin-Brosnan, J; Williams, D L; Kidd-Taylor, A; Shea, M; Breysse, P N; Hansel, N N

2014-08-01

Nitrogen dioxide (NO2 ), a by-product of combustion produced by indoor gas appliances such as cooking stoves, is associated with respiratory symptoms in those with obstructive airways disease. We conducted a three-armed randomized trial to evaluate the efficacy of interventions aimed at reducing indoor NO2 concentrations in homes with unvented gas stoves: (i) replacement of existing gas stove with electric stove; (ii) installation of ventilation hood over existing gas stove; and (iii) placement of air purifiers with high-efficiency particulate air (HEPA) and carbon filters. Home inspection and NO2 monitoring were conducted at 1 week pre-intervention and at 1 week and 3 months post-intervention. Stove replacement resulted in a 51% and 42% decrease in median NO2 concentration at 3 months of follow-up in the kitchen and bedroom, respectively (P = 0.01, P = 0.01); air purifier placement resulted in an immediate decrease in median NO2 concentration in the kitchen (27%, P kitchen (20%, P = 0.05). NO2 concentrations in the kitchen and bedroom did not significantly change following ventilation hood installation. Replacing unvented gas stoves with electric stoves or placement of air purifiers with HEPA and carbon filters can decrease indoor NO2 concentrations in urban homes. Several combustion sources unique to the residential indoor environment, including gas stoves, produce nitrogen dioxide (NO2), and higher NO2 concentrations, are associated with worse respiratory morbidity in people with obstructive lung disease. A handful of studies have modified the indoor environment by replacing unvented gas heaters; this study, to our knowledge, is the first randomized study to target unvented gas stoves. The results of this study show that simple home interventions, including replacement of an unvented gas stove with an electric stove or placement of HEPA air purifiers with carbon filters, can significantly decrease indoor NO2 concentrations. © 2013 John Wiley & Sons A

Development of an Indoor Location Based Service Test Bed and Geographic Information System with a Wireless Sensor Network

Science.gov (United States)

Jan, Shau-Shiun; Hsu, Li-Ta; Tsai, Wen-Ming

2010-01-01

In order to provide the seamless navigation and positioning services for indoor environments, an indoor location based service (LBS) test bed is developed to integrate the indoor positioning system and the indoor three-dimensional (3D) geographic information system (GIS). A wireless sensor network (WSN) is used in the developed indoor positioning system. Considering the power consumption, in this paper the ZigBee radio is used as the wireless protocol, and the received signal strength (RSS) fingerprinting positioning method is applied as the primary indoor positioning algorithm. The matching processes of the user location include the nearest neighbor (NN) algorithm, the K-weighted nearest neighbors (KWNN) algorithm, and the probabilistic approach. To enhance the positioning accuracy for the dynamic user, the particle filter is used to improve the positioning performance. As part of this research, a 3D indoor GIS is developed to be used with the indoor positioning system. This involved using the computer-aided design (CAD) software and the virtual reality markup language (VRML) to implement a prototype indoor LBS test bed. Thus, a rapid and practical procedure for constructing a 3D indoor GIS is proposed, and this GIS is easy to update and maintenance for users. The building of the Department of Aeronautics and Astronautics at National Cheng Kung University in Taiwan is used as an example to assess the performance of various algorithms for the indoor positioning system. PMID:22319282

Development of an Indoor Location Based Service Test Bed and Geographic Information System with a Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Shau-Shiun Jan

2010-03-01

Full Text Available In order to provide the seamless navigation and positioning services for indoor environments, an indoor location based service (LBS test bed is developed to integrate the indoor positioning system and the indoor three-dimensional (3D geographic information system (GIS. A wireless sensor network (WSN is used in the developed indoor positioning system. Considering the power consumption, in this paper the ZigBee radio is used as the wireless protocol, and the received signal strength (RSS fingerprinting positioning method is applied as the primary indoor positioning algorithm. The matching processes of the user location include the nearest neighbor (NN algorithm, the K-weighted nearest neighbors (KWNN algorithm, and the probabilistic approach. To enhance the positioning accuracy for the dynamic user, the particle filter is used to improve the positioning performance. As part of this research, a 3D indoor GIS is developed to be used with the indoor positioning system. This involved using the computer-aided design (CAD software and the virtual reality markup language (VRML to implement a prototype indoor LBS test bed. Thus, a rapid and practical procedure for constructing a 3D indoor GIS is proposed, and this GIS is easy to update and maintenance for users. The building of the Department of Aeronautics and Astronautics at National Cheng Kung University in Taiwan is used as an example to assess the performance of various algorithms for the indoor positioning system.

Indoor gamma dose measurements in Gudalore (India) using TLD

International Nuclear Information System (INIS)

Sivakumar, R.; Selvasekarapandian, S.; Mugunthamanikandan, N.; Raghunath, V.M.

2002-01-01

Indoor gamma radiation dose rates were measured inside residential buildings in Gudalore using a CaSO 4 : Dy thermoluminescent dosimeter for 1 year . Significant seasonal variations are observed. The highest dose rate is observed during summer and the lowest in winter. The dose rates observed are between 77.9 and 229.3 nGy h -1 and may be attributed to the type of building materials used in the dwellings monitored. The calculated mean annual effective dose equivalent rates range between 477.6 μSv y -1 , for the inhabitants of mud houses to 1406.3 μSv y -1 , for those living in terrace houses made of cement and brick

In-plane user positioning indoors

NARCIS (Netherlands)

Jovanovic, N.; Özçelebi, T.; Lukkien, J.J.; Skoric, B.; Ignatenko, T.

2014-01-01

Indoor positioning is a service required by many smart environment applications for various purposes, such as activity classification, indoor navigation and context awareness. In this paper, we present a novel approach to the user positioning problem based on in-plane detection enabled by a set of

Bioaerosols in residential micro-environments in low income countries: A case study from Pakistan

International Nuclear Information System (INIS)

Nasir, Zaheer Ahmad; Colbeck, Ian; Sultan, Sikander; Ahmed, Shakil

2012-01-01

Our knowledge of the concentrations of bioaerosols in residential micro-environments in low income countries is scanty. The present investigation was conducted to assess the culturable concentration and size distribution of bacteria, gram negative bacteria and fungi in two rural and an urban site in Pakistan. The highest indoor culturable bacteria concentration was found at Rural Site II (14,650 CFU/m 3 ) while the outdoor maximum occurred at the urban site (16,416 CFU/m 3 ). With reference to fungi, both indoor and outdoor concentrations were considerably higher at Rural Site I than the other sites. The size distribution of culturable bacteria at all sites showed greater variability than that of culturable fungi. At all sites more than the half (55–93%) of the culturable bacterial and fungal counts were observed in the respirable fraction ( 3 in the indoor environment. ► Elevated levels outdoors due to proximity to cattle and poor sanitary conditions. ► More that 50% of the bacterial and fungal aerosols were respirable. ► Possible increased respiratory exposure of inhabitants. - Bioaerosol concentrations up to 14,650 CFU/m 3 were measured in the indoor environment reflecting the proximity to cattle and poor sanitary conditions. These elevated levels pose a significant health risk.

Fugacity analysis of polycyclic aromatic hydrocarbons between microplastics and seawater

Science.gov (United States)

Lee, Hwang; Chang, Sein; Kim, Seung-Kyu; Kwon, Jung-Hwan

2017-03-01

Recently, the accumulation of plastic debris in the marine environment has become a great concern worldwide. Although plastics are biologically and chemically inert, plastic debris has been suspected of causing adverse effects on ecosystems due to the increase in reactivity by size reduction and/or micropollutants associated with plastics. Because of the high sorption capacity of microplastics toward organic micropollutants, it is suspected that microplastics may play roles in the distribution and fate of micropollutants. In order to quantitatively evaluate the "net flow" of environmental contaminants in water-plastic-organism systems, a fugacity analysis was conducted using concentrations of polycyclic aromatic hydrocarbons (PAHs) in open oceans and in polyethylene as a representative material of plastic debris. Ratio of fugacity in polyethylene to that in seawater showed a decreasing trend with increasing partition coefficient between polyethylene and seawater (KPE/sw). This indicates that phase equilibrium between polyethylene and seawater is not attained for higher molecular weight PAHs. Disequilibrium of high molecular weight PAHs suggests that transfer from seawater to plastic debris is thermodynamically driven and the role of plastic debris as a vector to transfer them to living organisms would be minimal. However, additives may slowly migrate from plastics into the environment causing potentially serious effects on ecosystems.

Effect of oxygen fugacity on OH dissolution in olivine under peridotite-saturated conditions: An experimental study at 1.5-7 GPa and 1100-1300 °C

Science.gov (United States)

Yang, Xiaozhi

2016-01-01

The dissolution of OH in olivine by experimental studies at simulated conditions has attracted increasing interest over the past three decades, and the influence of pressure, temperature and composition has been relatively well constrained. Oxygen fugacity is highly heterogeneous in the upper mantle, on both temporal and spatial scales, and is an important parameter in characterizing many chemical and physical processes in the mantle. However, less attention has been devoted to the effect of oxygen fugacity on OH dissolution in olivine, and the only few available reports on this topic have led to significant inconsistency and debate. In this study, the correlation between oxygen fugacity and OH solubility in Fe-bearing olivine has been systematically investigated by conducting experiments at 1.5-7 GPa and 1100-1300 °C and under peridotite- and fluid-saturated conditions, with natural gem-quality olivine single crystals and fresh peridotite xenoliths as starting materials and with oxygen fugacity controlled by the Fe-FeO, Ni-NiO and Fe2O3-Fe3O4 oxygen buffer pairs. The water concentrations were determined by polarized analyses using a Fourier-transform infrared spectroscopy. The results show that, at all the experimental conditions, the OH bands at both high frequency (∼3650-3450 cm-1) and low frequency (∼3450-3100 cm-1) are prominent. The intensity of OH bands at ∼3355 and 3325 cm-1 increases positively with oxygen fugacity, suggesting a dominant role of Fe3+ in their incorporation. Under otherwise identical conditions, the water content is gradually enhanced with increasing pressure, temperature or oxygen fugacity. The effect of oxygen fugacity on the enhancement of OH solubility appears not sensitive to temperature (1100-1300 °C) at a given pressure, but becomes progressively stronger with increasing pressure from 1.5 to 7 GPa given the temperature. Relative to oxygen fugacity buffers, the OH solubility is on average increased by ∼50% between Fe-FeO and

Rethinking Indoor Localization Solutions Towards the Future of Mobile Location-Based Services

Science.gov (United States)

Guney, C.

2017-11-01

Satellite navigation systems with GNSS-enabled devices, such as smartphones, car navigation systems, have changed the way users travel in outdoor environment. GNSS is generally not well suited for indoor location and navigation because of two reasons: First, GNSS does not provide a high level of accuracy although indoor applications need higher accuracies. Secondly, poor coverage of satellite signals for indoor environments decreases its accuracy. So rather than using GNSS satellites within closed environments, existing indoor navigation solutions rely heavily on installed sensor networks. There is a high demand for accurate positioning in wireless networks in GNSS-denied environments. However, current wireless indoor positioning systems cannot satisfy the challenging needs of indoor location-aware applications. Nevertheless, access to a user's location indoors is increasingly important in the development of context-aware applications that increases business efficiency. In this study, how can the current wireless location sensing systems be tailored and integrated for specific applications, like smart cities/grids/buildings/cars and IoT applications, in GNSS-deprived areas.

RETHINKING INDOOR LOCALIZATION SOLUTIONS TOWARDS THE FUTURE OF MOBILE LOCATION-BASED SERVICES

Directory of Open Access Journals (Sweden)

C. Guney

2017-11-01

Full Text Available Satellite navigation systems with GNSS-enabled devices, such as smartphones, car navigation systems, have changed the way users travel in outdoor environment. GNSS is generally not well suited for indoor location and navigation because of two reasons: First, GNSS does not provide a high level of accuracy although indoor applications need higher accuracies. Secondly, poor coverage of satellite signals for indoor environments decreases its accuracy. So rather than using GNSS satellites within closed environments, existing indoor navigation solutions rely heavily on installed sensor networks. There is a high demand for accurate positioning in wireless networks in GNSS-denied environments. However, current wireless indoor positioning systems cannot satisfy the challenging needs of indoor location-aware applications. Nevertheless, access to a user’s location indoors is increasingly important in the development of context-aware applications that increases business efficiency. In this study, how can the current wireless location sensing systems be tailored and integrated for specific applications, like smart cities/grids/buildings/cars and IoT applications, in GNSS-deprived areas.

Estimation of bias with the single-zone assumption in measurement of residential air exchange using the perfluorocarbon tracer gas method.

Science.gov (United States)

Van Ryswyk, K; Wallace, L; Fugler, D; MacNeill, M; Héroux, M È; Gibson, M D; Guernsey, J R; Kindzierski, W; Wheeler, A J

2015-12-01

Residential air exchange rates (AERs) are vital in understanding the temporal and spatial drivers of indoor air quality (IAQ). Several methods to quantify AERs have been used in IAQ research, often with the assumption that the home is a single, well-mixed air zone. Since 2005, Health Canada has conducted IAQ studies across Canada in which AERs were measured using the perfluorocarbon tracer (PFT) gas method. Emitters and detectors of a single PFT gas were placed on the main floor to estimate a single-zone AER (AER(1z)). In three of these studies, a second set of emitters and detectors were deployed in the basement or second floor in approximately 10% of homes for a two-zone AER estimate (AER(2z)). In total, 287 daily pairs of AER(2z) and AER(1z) estimates were made from 35 homes across three cities. In 87% of the cases, AER(2z) was higher than AER(1z). Overall, the AER(1z) estimates underestimated AER(2z) by approximately 16% (IQR: 5-32%). This underestimate occurred in all cities and seasons and varied in magnitude seasonally, between homes, and daily, indicating that when measuring residential air exchange using a single PFT gas, the assumption of a single well-mixed air zone very likely results in an under prediction of the AER. The results of this study suggest that the long-standing assumption that a home represents a single well-mixed air zone may result in a substantial negative bias in air exchange estimates. Indoor air quality professionals should take this finding into consideration when developing study designs or making decisions related to the recommendation and installation of residential ventilation systems. © 2014 Her Majesty the Queen in Right of Canada. Indoor Air published by John Wiley & Sons Ltd Reproduced with the permission of the Minister of Health Canada.

Indoor Localisation Based on GSM Signals: Multistorey Building Study

Directory of Open Access Journals (Sweden)

Rafał Górak

2016-01-01

Full Text Available Among the accurate indoor localisation systems that are using WiFi, Bluetooth, or infrared technologies, the ones that are based on the GSM rely on a stable external infrastructure that can be used even in an emergency. This paper presents an accurate GSM indoor localisation system that achieves a median error of 4.39 metres in horizontal coordinates and up to 64 percent accuracy in floor prediction (for 84 percent of cases the floor prediction is mistaken by not more than a single floor. The test and reference measurements were made inside a six-floor academic building, with an irregular shape, whose dimensions are around 50 metres by 70 metres. The localisation algorithm uses GSM signal readings from the 7 strongest cells available in the GSM standard (or fewer, if fewer than 7 are available. We estimate the location by a three-step method. Firstly, we propose a point localisation solution (i.e., localisation based on only one measurement. Then, by applying the central tendency filters and the Multilayer Perceptron, we build a localisation system that uses a sequence of estimations of current and past locations. We also discuss major accuracy factors such as the number of observed signals or the types of spaces in the building.

Performance-based potential for residential energy efficiency

Energy Technology Data Exchange (ETDEWEB)

Performance-based potential for residential energy efficiency

2013-01-15

Energy performance contracts (EPCs) have proven an effective mechanism for increasing energy efficiency in nearly all sectors of the economy since their introduction nearly 30 years ago. In the modern form, activities undertaken as part of an EPC are scoped and implemented by experts with specialized technical knowledge, financed by commercial lenders, and enable a facility owner to limit risk and investment of time and resources while receiving the rewards of improved energy performance. This report provides a review of the experiences of the US with EPCs and discusses the possibilities for the residential sector to utilize EPCs. Notably absent from the EPC market is the residential segment. Historically, research has shown that the residential sector varies in several key ways from markets segments where EPCs have proven successful, including: high degree of heterogeneity of energy use characteristics among and within households, comparatively small quantity of energy consumed per residence, limited access to information about energy consumption and savings potential, and market inefficiencies that constrain the value of efficiency measures. However, the combination of recent technological advances in automated metering infrastructure, flexible financing options, and the expansion of competitive wholesale electricity markets to include energy efficiency as a biddable supply-side resource present an opportunity for EPC-like efforts to successfully engage the residential sector, albeit following a different model than has been used in EPCs traditionally.(Author)

Potentials and Challenges of Light Fidelity Based Indoor Communication System

OpenAIRE

Aftab, Farooq

2016-01-01

In this era of modern devices and high speed communication the issue of spectral overloading is increasing with time and becoming more serious. With the advancement in LED industry, light fidelity (Li-Fi) based indoor network is an attractive substitute for the existing radio frequency (RF) based communication networks. Because of its capability to perform dual function of lighting as well as high speed communication, Li-Fi is attracting both industrial as well as academic researchers. The Li...

An Indoor Monitoring System for Ambient Assisted Living Based on Internet of Things Architecture

Science.gov (United States)

Marques, Gonçalo; Pitarma, Rui

2016-01-01

The study of systems and architectures for ambient assisted living (AAL) is undoubtedly a topic of great relevance given the aging of the world population. The AAL technologies are designed to meet the needs of the aging population in order to maintain their independence as long as possible. As people typically spend more than 90% of their time in indoor environments, indoor air quality (iAQ) is perceived as an imperative variable to be controlled for the inhabitants’ wellbeing and comfort. Advances in networking, sensors, and embedded devices have made it possible to monitor and provide assistance to people in their homes. The continuous technological advancements make it possible to build smart objects with great capabilities for sensing and connecting several possible advancements in ambient assisted living systems architectures. Indoor environments are characterized by several pollutant sources. Most of the monitoring frameworks instantly accessible are exceptionally costly and only permit the gathering of arbitrary examples. iAQ is an indoor air quality system based on an Internet of Things paradigm that incorporates in its construction Arduino, ESP8266, and XBee technologies for processing and data transmission and micro sensors for data acquisition. It also allows access to data collected through web access and through a mobile application in real time, and this data can be accessed by doctors in order to support medical diagnostics. Five smaller scale sensors of natural parameters (air temperature, moistness, carbon monoxide, carbon dioxide, and glow) were utilized. Different sensors can be included to check for particular contamination. The results reveal that the system can give a viable indoor air quality appraisal in order to anticipate technical interventions for improving indoor air quality. Indeed indoor air quality might be distinctively contrasted with what is normal for a quality living environment. PMID:27869682

An Indoor Monitoring System for Ambient Assisted Living Based on Internet of Things Architecture

Directory of Open Access Journals (Sweden)

Gonçalo Marques

2016-11-01

Full Text Available The study of systems and architectures for ambient assisted living (AAL is undoubtedly a topic of great relevance given the aging of the world population. The AAL technologies are designed to meet the needs of the aging population in order to maintain their independence as long as possible. As people typically spend more than 90% of their time in indoor environments, indoor air quality (iAQ is perceived as an imperative variable to be controlled for the inhabitants’ wellbeing and comfort. Advances in networking, sensors, and embedded devices have made it possible to monitor and provide assistance to people in their homes. The continuous technological advancements make it possible to build smart objects with great capabilities for sensing and connecting several possible advancements in ambient assisted living systems architectures. Indoor environments are characterized by several pollutant sources. Most of the monitoring frameworks instantly accessible are exceptionally costly and only permit the gathering of arbitrary examples. iAQ is an indoor air quality system based on an Internet of Things paradigm that incorporates in its construction Arduino, ESP8266, and XBee technologies for processing and data transmission and micro sensors for data acquisition. It also allows access to data collected through web access and through a mobile application in real time, and this data can be accessed by doctors in order to support medical diagnostics. Five smaller scale sensors of natural parameters (air temperature, moistness, carbon monoxide, carbon dioxide, and glow were utilized. Different sensors can be included to check for particular contamination. The results reveal that the system can give a viable indoor air quality appraisal in order to anticipate technical interventions for improving indoor air quality. Indeed indoor air quality might be distinctively contrasted with what is normal for a quality living environment.

An Indoor Monitoring System for Ambient Assisted Living Based on Internet of Things Architecture.

Science.gov (United States)

Marques, Gonçalo; Pitarma, Rui

2016-11-17

The study of systems and architectures for ambient assisted living (AAL) is undoubtedly a topic of great relevance given the aging of the world population. The AAL technologies are designed to meet the needs of the aging population in order to maintain their independence as long as possible. As people typically spend more than 90% of their time in indoor environments, indoor air quality (iAQ) is perceived as an imperative variable to be controlled for the inhabitants' wellbeing and comfort. Advances in networking, sensors, and embedded devices have made it possible to monitor and provide assistance to people in their homes. The continuous technological advancements make it possible to build smart objects with great capabilities for sensing and connecting several possible advancements in ambient assisted living systems architectures. Indoor environments are characterized by several pollutant sources. Most of the monitoring frameworks instantly accessible are exceptionally costly and only permit the gathering of arbitrary examples. iAQ is an indoor air quality system based on an Internet of Things paradigm that incorporates in its construction Arduino, ESP8266, and XBee technologies for processing and data transmission and micro sensors for data acquisition. It also allows access to data collected through web access and through a mobile application in real time, and this data can be accessed by doctors in order to support medical diagnostics. Five smaller scale sensors of natural parameters (air temperature, moistness, carbon monoxide, carbon dioxide, and glow) were utilized. Different sensors can be included to check for particular contamination. The results reveal that the system can give a viable indoor air quality appraisal in order to anticipate technical interventions for improving indoor air quality. Indeed indoor air quality might be distinctively contrasted with what is normal for a quality living environment.

The Isprs Benchmark on Indoor Modelling

Science.gov (United States)

Khoshelham, K.; Díaz Vilariño, L.; Peter, M.; Kang, Z.; Acharya, D.

2017-09-01

Automated generation of 3D indoor models from point cloud data has been a topic of intensive research in recent years. While results on various datasets have been reported in literature, a comparison of the performance of different methods has not been possible due to the lack of benchmark datasets and a common evaluation framework. The ISPRS benchmark on indoor modelling aims to address this issue by providing a public benchmark dataset and an evaluation framework for performance comparison of indoor modelling methods. In this paper, we present the benchmark dataset comprising several point clouds of indoor environments captured by different sensors. We also discuss the evaluation and comparison of indoor modelling methods based on manually created reference models and appropriate quality evaluation criteria. The benchmark dataset is available for download at: html"target="_blank">http://www2.isprs.org/commissions/comm4/wg5/benchmark-on-indoor-modelling.html.

The Effect of Pressure on Iron Speciation in Silicate Melts at a Fixed Oxygen Fugacity: The Possibility of a Redox Profile Through a Terrestrial Magma Ocean

Science.gov (United States)

Armstrong, K.; Frost, D. J.; McCammon, C. A.; Rubie, D. C.; Boffa Ballaran, T.

2017-12-01

As terrestrial planets accreted, mantle silicates equilibrated with core-forming metallic iron, which would have imposed a mantle oxygen fugacity below the iron-wüstite oxygen buffer. Throughout Earth's history, however, the oxygen fugacity of at least the accessible portions of the upper mantle has been 4-5 orders of magnitude higher. The process that caused the rapid increase in the redox state of the mantle soon after core formation is unclear. Here we test the possibility that pressure stabilises ferric iron in silicate melts, as has been observed in silicate minerals. A deep magma ocean, which would have likely existed towards the end of accretion, could then develop a gradient in oxygen fugacity for a fixed ferric-ferrous ratio as a result of pressure. We have equilibrated an andesitic melt with a Ru-RuO2 buffer in a multianvil press between 5 and 24 GPa. Further experiments were performed on the same melt in equilibrium with iron metal. The recovered melts were then analysed using Mössbauer spectroscopy to determine the ferric/ferrous ratio. The results show that for the Ru-RuO2 buffer at lower pressures, the ferric iron content decreases with pressure, due to a positive volume change of the reaction FeO + 1/4O2 = FeO1.5. Ferric iron content also appears to be sensitive to water content at lower pressures. However, above 15 GPa this trend apparently reverses and the ferric iron content increases with pressure. This reversal in pressure dependence would drive the oxygen fugacity of a deep magma ocean with a fixed ferric/ferrous ratio down with increasing depth. This would create a redox gradient, where the magma ocean could potentially be in equilibrium with metallic iron at its base but more oxidised in its shallower regions. Crystallisation of this magma ocean could render an upper mantle oxygen fugacity similar to that in the Earth's accessible mantle today.

EU Project “School of the Future”— Refurbishment of School Buildings Toward Zero Emission with High-Performance Indoor Environment

DEFF Research Database (Denmark)

Erhorn-Kluttig, Heike; Erhorn, Hans; Kempe, Stephan

2016-01-01

:•Reduction of the total energy use > factor of 3, verified through monitoring•Reduction of the heating energy use > 75%, verified through monitoring.The improvement of the indoor environment quality (air, daylight, acoustic, thermal comfort) and the associated impact on the students’ performance will be analyzed by short......, and their primary users, namely students, i.e., the next generation, are the focus of the project. The energy and indoor environment performance of four demonstration buildings in four European countries and climates have been significantly improved due to holistic retrofits of the building envelope, their service...... and on the residential sector since the students will act as communicators to their families. Training sessions specifically tailored to their needs have improved user behavior and awareness of energy efficiency and indoor environment. The success is measured by how well the retrofits meet the following goals...

Indoor air quality – buildings design

Directory of Open Access Journals (Sweden)

Juhásová Šenitková Ingrid

2017-01-01

Full Text Available Growing attention is being paid to indoor air quality as one of the main health and well-being factors. The indoor research is concerned mostly to indoor air chemicals within indoor engineering related to building design. The providing good indoor air quality can be achieved effectively by avoiding or reducing indoor air pollution sources and by selecting low-polluting building materials, both being low-cost and energyefficient solutions. On the base of the last large experimental monitoring results, it was possible to know the level of selected indoor chemicals occurrence, rank them as well as to predict the tendencies of occurrence and establish the priorities for the future. There has been very limited attention to rigorous analysis of buildings actual environmental impacts to date. Healthy/green/sustainable building practices are typically applied in unsystematic and inconsistent ways often without resolution of inherent conflicts between and among such practices. Designers, products manufacturers, constructors, and owners declare their buildings and the applied technologies to be beneficial to the environment without validating those claims.

Statistical analysis of electromagnetic radiation measurements in the vicinity of indoor microcell GSM/UMTS base stations in Serbia.

Science.gov (United States)

Koprivica, Mladen; Petrić, Majda; Nešković, Nataša; Nešković, Aleksandar

2016-01-01

To determine the level of radiofrequency radiation generated by base stations of Global System for Mobile Communications and Universal Mobile Telecommunication System, extensive electromagnetic field strength measurements were carried out in the vicinity of 664 base station locations. These were classified into three categories: indoor, masts, and locations with installations on buildings. Although microcell base stations with antennas installed indoors typically emit less power than outdoor macrocell base stations, the fact that people can be found close to antennas requires exposure originating from these base stations to be carefully considered. Measurement results showed that maximum recorded value of electric field strength exceeded International Commission on Non-Ionizing Radiation Protection reference levels at 7% of indoor base station locations. At the same time, this percentage was much lower in the case of masts and installations on buildings (0% and 2.5%, respectively). © 2015 Wiley Periodicals, Inc.

Peripheral and gastrointestinal immune systems of healthy cattle raised outdoors at pasture or indoors on a concentrate-based ration.

Science.gov (United States)

Lejeune, Alexandre; Monahan, Frank J; Moloney, Aidan P; Earley, Bernadette; Black, Alistair D; Campion, Deirdre P; Englishby, Tanya; Reilly, Petrina; O'Doherty, John; Sweeney, Torres

2010-03-31

Despite an increasing preference of consumers for beef produced from more extensive pasture-based production systems and potential human health benefits from the consumption of such beef, data regarding the health status of animals raised on pasture are limited. The objective of this study was to characterise specific aspects of the bovine peripheral and the gastrointestinal muscosal immune systems of cattle raised on an outdoor pasture system in comparison to animals raised on a conventional intensive indoor concentrate-based system. A number of in vitro functional tests of immune cells suggested subtle differences between the animals on the outdoor versus indoor production systems. There was a decrease in the number of neutrophils and monocytes engaged in phagocytosis in outdoor cattle (P outdoor animals (P outdoor animals with elevated levels of serum pepsinogen (P outdoor animals in comparison to the indoor animals. Lower levels of copper and iodine were measured in the outdoor animals in comparison to indoor animals (P < 0.001). Despite distinctly contrasting production systems, only subtle differences were identified in the peripheral immune parameters measured between cattle raised at pasture in comparison to animals raised on a conventional intensive indoor concentrate-based production system.

Residential hospice environments: evidence-based architectural and landscape design considerations.

Science.gov (United States)

Verderber, Stephen

2014-01-01

The residential hospice care movement is increasingly accepted and supported globally, and yet, unfortunately, the amount of literature on best practices in the planning and design of residential hospice facilities and adjacent outdoor spaces remains relatively small. This paper reports on a compendium of architectural and landscape design considerations that reflect the fundamental dimensions of the residential hospice experience: site and context, arrival spaces, communal and private spaces of the residential milieu, transitional spaces, and nature connectivity. Additionally, key staffing and administrative ramifications of this built-environment compendium are addressed, as are prognostications and challenges for the future.

Effectiveness of Indoor Plant to Reduce CO2 in Indoor Environment

Directory of Open Access Journals (Sweden)

Suhaimi Mohd Mahathir

2017-01-01

Full Text Available Modern country strongly emphasizes on indoor air quality (IAQ because it can effect on human health and productivity. Numerous efforts were performed to make sure that sustainability of IAQ is guaranteed. In the last 4th decade, researchers discover that indoor plants have abilities to reduce indoor air pollution. Generally, plants, carbon dioxide (CO2, light, and temperature involve in the photosynthesis process. This paper intends to study the effectiveness of seven indoor plants (Anthurium, Dumb Cane, Golden Pothos, Kadaka Fern, Prayer Plant, Spider Plant, and Syngonium to reduce CO2 with different light level. This study was conducted in one cubic meter of chamber, and each plant was put into the chamber individually with CO2 concentration in the chamber is set at 1000±50ppm, and light intensities is set at 300 and 700 lux, while temperature were fixed at 25±1°C. Based on the results, only the Spider Plant was not able to absorb CO2 during the test at 300 lux of light intensity. Meanwhile, Prayer Plant performed well when tested at 300 or 700 lux of light intensity compare to other investigates plants. This study can conclude that light intensity play an important role for the plant to absorb CO2 effectively. All the indoor plants absorbed more CO2, when the light intensity is increased.

NFC Internal: An Indoor Navigation System

Science.gov (United States)

Ozdenizci, Busra; Coskun, Vedat; Ok, Kerem

2015-01-01

Indoor navigation systems have recently become a popular research field due to the lack of GPS signals indoors. Several indoors navigation systems have already been proposed in order to eliminate deficiencies; however each of them has several technical and usability limitations. In this study, we propose NFC Internal, a Near Field Communication (NFC)-based indoor navigation system, which enables users to navigate through a building or a complex by enabling a simple location update, simply by touching NFC tags those are spread around and orient users to the destination. In this paper, we initially present the system requirements, give the design details and study the viability of NFC Internal with a prototype application and a case study. Moreover, we evaluate the performance of the system and compare it with existing indoor navigation systems. It is seen that NFC Internal has considerable advantages and significant contributions to existing indoor navigation systems in terms of security and privacy, cost, performance, robustness, complexity, user preference and commercial availability. PMID:25825976

Residential characteristics and household risk factors and respiratory diseases in Chinese women: The Seven Northeast Cities (SNEC) Study

Energy Technology Data Exchange (ETDEWEB)

Dong, Guang-Hui [Department of Biostatistics and Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province 110001 (China); Department of Occupational and Environmental Health, School of Public Health, China Medical University, Shenyang, Liaoning Province 110001 (China); Qian, Zhengmin, E-mail: zqian2@slu.edu [Department of Epidemiology, School of Public Health, Saint Louis University, Saint Louis, MO 63104 (United States); Wang, Jing [Department of Biostatistics, School of Public Health, Saint Louis University, Saint Louis, MO 63104 (United States); Trevathan, Edwin [Department of Epidemiology, School of Public Health, Saint Louis University, Saint Louis, MO 63104 (United States); Ma, Wenjun [Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, Guangdong Province 510300 (China); Chen, Weiqing [Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou 510080 (China); Xaverius, Pamela K.; Buckner-Petty, Skye; Ray, Asheesh [Department of Epidemiology, School of Public Health, Saint Louis University, Saint Louis, MO 63104 (United States); Liu, Miao-Miao; Wang, Da [Department of Biostatistics and Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province 110001 (China); Ren, Wan-Hui [Department of Ambient Air Pollution Monitor, Shenyang Environmental Monitoring Center, Shenyang, Liaoning Province 110014 (China); Emo, Brett [Department of Environmental and Occupational Health School of Public Health, Saint Louis University, Saint Louis, MO 63104 (United States); Chang, Jen-Jen [Department of Epidemiology, School of Public Health, Saint Louis University, Saint Louis, MO 63104 (United States)

2013-10-01

Background: Few studies have assessed the impact of residential home characteristics and home environmental risk factors on respiratory diseases in Chinese women. Therefore, this study sought to determine the association between residential home features, domestic pets, home renovation and other indoor environmental risk factors with respiratory health outcomes of Chinese women. Methods: This cross-sectional study included a study sample of 30,780 Chinese women aged 23 to 49 from 25 districts of seven cities in Liaoning Province, Northeast China. Information on respiratory health, residential characteristics, and indoor air pollution sources was obtained by a standard questionnaire from the American Thoracic Society. Multivariable logistic regression was used to estimate prevalence odds ratios (POR) and 95% confidence interval (95%CI). Results: The odds of respiratory diseases were higher for those who lived near the main road, or near ambient air pollution sources. Pet-keeping was associated with increased odds of chronic bronchitis (POR = 1.40; 95%CI: 1.09–1.81) and doctor-diagnosed asthma (POR = 2.07; 95%CI: 1.18–3.64). Additionally, humidifier use was associated with increased odds of chronic bronchitis (POR = 1.44; 95%CI: 1.07–1.94). Home renovation in recent 2 years was associated with increased likelihood of allergic rhinitis (POR = 1.39; 95%CI 1.17–1.64). Conclusion: Home renovation and residential home environmental risk factors were associated with an increased likelihood of respiratory morbidity among Chinese women. - Highlights: • Relatively few significant associations were observed. • Pet ownership was associated with increased odds of asthma and chronic bronchitis. • Home renovation was associated with increased odds of allergic rhinitis in women. • Humidifier use was associated with increased odds of chronic bronchitis in women.

Residential characteristics and household risk factors and respiratory diseases in Chinese women: The Seven Northeast Cities (SNEC) Study

International Nuclear Information System (INIS)

Dong, Guang-Hui; Qian, Zhengmin; Wang, Jing; Trevathan, Edwin; Ma, Wenjun; Chen, Weiqing; Xaverius, Pamela K.; Buckner-Petty, Skye; Ray, Asheesh; Liu, Miao-Miao; Wang, Da; Ren, Wan-Hui; Emo, Brett; Chang, Jen-Jen

2013-01-01

Background: Few studies have assessed the impact of residential home characteristics and home environmental risk factors on respiratory diseases in Chinese women. Therefore, this study sought to determine the association between residential home features, domestic pets, home renovation and other indoor environmental risk factors with respiratory health outcomes of Chinese women. Methods: This cross-sectional study included a study sample of 30,780 Chinese women aged 23 to 49 from 25 districts of seven cities in Liaoning Province, Northeast China. Information on respiratory health, residential characteristics, and indoor air pollution sources was obtained by a standard questionnaire from the American Thoracic Society. Multivariable logistic regression was used to estimate prevalence odds ratios (POR) and 95% confidence interval (95%CI). Results: The odds of respiratory diseases were higher for those who lived near the main road, or near ambient air pollution sources. Pet-keeping was associated with increased odds of chronic bronchitis (POR = 1.40; 95%CI: 1.09–1.81) and doctor-diagnosed asthma (POR = 2.07; 95%CI: 1.18–3.64). Additionally, humidifier use was associated with increased odds of chronic bronchitis (POR = 1.44; 95%CI: 1.07–1.94). Home renovation in recent 2 years was associated with increased likelihood of allergic rhinitis (POR = 1.39; 95%CI 1.17–1.64). Conclusion: Home renovation and residential home environmental risk factors were associated with an increased likelihood of respiratory morbidity among Chinese women. - Highlights: • Relatively few significant associations were observed. • Pet ownership was associated with increased odds of asthma and chronic bronchitis. • Home renovation was associated with increased odds of allergic rhinitis in women. • Humidifier use was associated with increased odds of chronic bronchitis in women

Indoor localization using magnetic fields

Science.gov (United States)

Pathapati Subbu, Kalyan Sasidhar

Indoor localization consists of locating oneself inside new buildings. GPS does not work indoors due to multipath reflection and signal blockage. WiFi based systems assume ubiquitous availability and infrastructure based systems require expensive installations, hence making indoor localization an open problem. This dissertation consists of solving the problem of indoor localization by thoroughly exploiting the indoor ambient magnetic fields comprising mainly of disturbances termed as anomalies in the Earth's magnetic field caused by pillars, doors and elevators in hallways which are ferromagnetic in nature. By observing uniqueness in magnetic signatures collected from different campus buildings, the work presents the identification of landmarks and guideposts from these signatures and further develops magnetic maps of buildings - all of which can be used to locate and navigate people indoors. To understand the reason behind these anomalies, first a comparison between the measured and model generated Earth's magnetic field is made, verifying the presence of a constant field without any disturbances. Then by modeling the magnetic field behavior of different pillars such as steel reinforced concrete, solid steel, and other structures like doors and elevators, the interaction of the Earth's field with the ferromagnetic fields is described thereby explaining the causes of the uniqueness in the signatures that comprise these disturbances. Next, by employing the dynamic time warping algorithm to account for time differences in signatures obtained from users walking at different speeds, an indoor localization application capable of classifying locations using the magnetic signatures is developed solely on the smart phone. The application required users to walk short distances of 3-6 m anywhere in hallway to be located with accuracies of 80-99%. The classification framework was further validated with over 90% accuracies using model generated magnetic signatures representing

A risk-based approach to health criteria for radon indoors -report on a WHO initiative

International Nuclear Information System (INIS)

Steinhaeusler, F.

1994-01-01

The World Health Organization (WHO), Regional Office for Europe, organised a meeting of a working group on indoor air quality in Eilat, Israel, from 28 March to 4 April 1993. The aim was to develop a risk-based approach to health criteria for radon indoors. The Group reviewed the latest epidemiological data from occupational and non-occupational radon exposure, animal experiments and dosimetry. The Group issued 14 conclusions and 23 recommendations on radon related risk to health, on risk management and risk communication. In summary, radon was confirmed as a human carcinogen. Indoor radon exposures resulting in individual risks exceeding 10 -3 per year are to be considered as severe and risk reduction programmes implemented. Guidance on risk management and communication is offered to national authorities. (author)

Indoor Positioning using Wi-Fi

DEFF Research Database (Denmark)

Kjærgaard, Mikkel Baun; Krarup, Mads Vering; Stisen, Allan

The past decade has witnessed substantial research on methods for indoor Wi-Fi positioning. While much effort has gone into achieving high positioning accuracy and easing fingerprint collection, it is our contention that the general problem is not sufficiently well understood, thus preventing...... deployments and their usage by applications to become more widespread. Based on our own and published experiences on indoor Wi-Fi positioning deployments, we hypothesize the following: Current indoor Wi-Fi positioning systems and their utilization in applications are hampered by the lack of understanding...... of the requirements present in the real-world deployments. In this paper, we report findings from qualitatively studying organisational requirements for indoor Wi-Fi positioning. The studied cases and deployments cover both company and public-sector settings and the deployment and evaluation of several types...

Energy Impacts of Effective Range Hood Use for all U.S. Residential Cooking

Energy Technology Data Exchange (ETDEWEB)

Logue, Jennifer M; Singer, Brett

2014-06-01

Range hood use during residential cooking is essential to maintaining good indoor air quality. However, widespread use will impact the energy demand of the U.S. housing stock. This paper describes a modeling study to determine site energy, source energy, and consumer costs for comprehensive range hood use. To estimate the energy impacts for all 113 million homes in the U.S., we extrapolated from the simulation of a representative weighted sample of 50,000 virtual homes developed from the 2009 Residential Energy Consumption Survey database. A physics-based simulation model that considered fan energy, energy to condition additional incoming air, and the effect on home heating and cooling due to exhausting the heat from cooking was applied to each home. Hoods performing at a level common to hoods currently in U.S. homes would require 19?33 TWh [69?120 PJ] of site energy, 31?53 TWh [110-190 PJ] of source energy; and would cost consumers $1.2?2.1 billion (U.S.$2010) annually in the U.S. housing stock. The average household would spend less than $15 annually. Reducing required airflow, e.g. with designs that promote better pollutant capture has more energy saving potential, on average, than improving fan efficiency.

Indoor air pollution

International Nuclear Information System (INIS)

Qureshi, I.H.

2001-01-01

Indoor air pollution is a potential risk to human health. Prolonged exposure to indoor pollutants may cause various infectious, allergic and other diseases. Indoor pollutants can emanate from a broad array of internal and external sources. Internal sources include building and furnishing materials, consumer and commercial products, office equipment, micro-organisms, pesticides and human occupants activities. External sources include soil, water supplies and outside makeup air. The main indoor air pollutants of concern are inorganic gases, formaldehyde and other volatile organic compounds, pesticides, radon and its daughters, particulates and microbes. The magnitude of human exposure to indoor pollutants can be estimated or predicted with the help of mathematical models which have been developed using the data from source emission testing and field monitoring of pollutants. In order to minimize human exposure to indoor pollutants, many countries have formulated guidelines / standards for the maximum permissible levels of main pollutants. Acceptable indoor air quality can be achieved by controlling indoor pollution sources and by effective ventilation system for removal of indoor pollutants. (author)

PRIMAL: Page Rank-Based Indoor Mapping and Localization Using Gene-Sequenced Unlabeled WLAN Received Signal Strength

Directory of Open Access Journals (Sweden)

Mu Zhou

2015-09-01

Full Text Available Due to the wide deployment of wireless local area networks (WLAN, received signal strength (RSS-based indoor WLAN localization has attracted considerable attention in both academia and industry. In this paper, we propose a novel page rank-based indoor mapping and localization (PRIMAL by using the gene-sequenced unlabeled WLAN RSS for simultaneous localization and mapping (SLAM. Specifically, first of all, based on the observation of the motion patterns of the people in the target environment, we use the Allen logic to construct the mobility graph to characterize the connectivity among different areas of interest. Second, the concept of gene sequencing is utilized to assemble the sporadically-collected RSS sequences into a signal graph based on the transition relations among different RSS sequences. Third, we apply the graph drawing approach to exhibit both the mobility graph and signal graph in a more readable manner. Finally, the page rank (PR algorithm is proposed to construct the mapping from the signal graph into the mobility graph. The experimental results show that the proposed approach achieves satisfactory localization accuracy and meanwhile avoids the intensive time and labor cost involved in the conventional location fingerprinting-based indoor WLAN localization.

PRIMAL: Page Rank-Based Indoor Mapping and Localization Using Gene-Sequenced Unlabeled WLAN Received Signal Strength.

Science.gov (United States)

Zhou, Mu; Zhang, Qiao; Xu, Kunjie; Tian, Zengshan; Wang, Yanmeng; He, Wei

2015-09-25

Due to the wide deployment of wireless local area networks (WLAN), received signal strength (RSS)-based indoor WLAN localization has attracted considerable attention in both academia and industry. In this paper, we propose a novel page rank-based indoor mapping and localization (PRIMAL) by using the gene-sequenced unlabeled WLAN RSS for simultaneous localization and mapping (SLAM). Specifically, first of all, based on the observation of the motion patterns of the people in the target environment, we use the Allen logic to construct the mobility graph to characterize the connectivity among different areas of interest. Second, the concept of gene sequencing is utilized to assemble the sporadically-collected RSS sequences into a signal graph based on the transition relations among different RSS sequences. Third, we apply the graph drawing approach to exhibit both the mobility graph and signal graph in a more readable manner. Finally, the page rank (PR) algorithm is proposed to construct the mapping from the signal graph into the mobility graph. The experimental results show that the proposed approach achieves satisfactory localization accuracy and meanwhile avoids the intensive time and labor cost involved in the conventional location fingerprinting-based indoor WLAN localization.

Indoor gamma dose measurements in Gudalore (India) using TLD

Energy Technology Data Exchange (ETDEWEB)

Sivakumar, R.; Selvasekarapandian, S. E-mail: spandian@bharathi.ernet.in; Mugunthamanikandan, N.; Raghunath, V.M

2002-06-01

Indoor gamma radiation dose rates were measured inside residential buildings in Gudalore using a CaSO{sub 4} : Dy thermoluminescent dosimeter for 1 year . Significant seasonal variations are observed. The highest dose rate is observed during summer and the lowest in winter. The dose rates observed are between 77.9 and 229.3 nGy h{sup -1} and may be attributed to the type of building materials used in the dwellings monitored. The calculated mean annual effective dose equivalent rates range between 477.6 {mu}Sv y{sup -1}, for the inhabitants of mud houses to 1406.3 {mu}Sv y{sup -1}, for those living in terrace houses made of cement and brick.

Identifying Typical Movements Among Indoor Objects

DEFF Research Database (Denmark)

Radaelli, Laura; Sabonis, Dovydas; Lu, Hua

2013-01-01

With the proliferation of mobile computing, positioning systems are becoming available that enable indoor location-based services. As a result, indoor tracking data is also becoming available. This paper puts focus on one use of such data, namely the identification of typical movement patterns...

Residential Radon Exposure and Incidence of Childhood Lymphoma in Texas, 1995–2011

Directory of Open Access Journals (Sweden)

Erin C. Peckham

2015-09-01

Full Text Available There is warranted interest in assessing the association between residential radon exposure and the risk of childhood cancer. We sought to evaluate the association between residential radon exposure and the incidence of childhood lymphoma in Texas. The Texas Cancer Registry (n = 2147 provided case information for the period 1995–2011. Denominator data were obtained from the United States Census. Regional arithmetic mean radon concentrations were obtained from the Texas Indoor Radon Survey and linked to residence at diagnosis. Exposure was assessed categorically: ≤25th percentile (reference, >25th to ≤50th percentile, >50th to ≤75th percentile, and >75th percentile. Negative binomial regression generated adjusted incidence rate ratios (aIRR and 95% confidence intervals (CI. We evaluated lymphoma overall and by subtype: Hodgkin (HL; n = 1248, Non-Hodgkin excluding Burkitt (non-BL NHL; n = 658, Burkitt (BL; n = 241, and Diffuse Large B-cell (DLBCL; n = 315. There was no evidence that residential radon exposure was positively associated with lymphoma overall, HL, or BL. Areas with radon concentrations >75th percentile had a marginal increase in DLBCL incidence (aIRR = 1.73, 95% CI: 1.03–2.91. In one of the largest studies of residential radon exposure and the incidence of childhood lymphoma, we found little evidence to suggest a positive or negative association; an observation consistent with previous studies.

Locating room air-conditioners at floor level for energy saving in residential buildings

Energy Technology Data Exchange (ETDEWEB)

Gao, C.F.; Lee, Hua; Chen, W.L. [Department of Building Services Engineering, Hong Kong Polytechnic University, Hung Hom (China)

2009-08-15

Residential air-conditioning becomes a common feature in our daily life. They are typically installed at high level known as ceiling-based system (CAC). With the increasing use of floor-based air-conditioning system in commercial buildings for energy saving, it is proposed in this study to locate a top discharge/front return air-conditioner at floor level to resemble a floor-based air-conditioning system (FAC) to curb energy use in residential buildings. Given the concerns about draught discomfort and thermal stratification associated with floor-based air-conditioning systems, the objective of this study is to evaluate the air distribution performance and to quantify the possible energy benefits. Bedroom was chosen as a sensitive case for detailed air distribution performance evaluation. Experimental study, CFD simulations and energy simulations were conducted in achieving the specific objectives. CAC and FAC were installed in a bedroom-like environmental chamber for experimental study at different indoor and outdoor conditions. The air velocities and temperatures at various positions and levels inside the chamber were measured to determine the air distribution performance indices (ADPI) and airflow draft risk (DR). The cooling output, power consumption and coefficient of performance (COP) of the two units were measured and calculated for comparison. The experimental results show that ADPI of CAC and FAC are 92.3% and 84.6%, respectively. COP of FAC is 8.11% higher than CAC, and the corresponding DR are comparable. The experimental results were used to validate the CFD simulations as well as providing actual performance data for predicting the energy use of applying CAC and FAC in a case-study building. CFD simulations and draught assessment confirmed that there is no potential draught discomfort and thermal stratification associated with the use of FAC. Energy simulations predicted that the associated energy saving is 6.9%. Wider use of FAC in residential

Understanding Residential Polarization in a Globalizing City

Directory of Open Access Journals (Sweden)

Ibrahim Rotimi Aliu

2013-12-01

Full Text Available This study examines the spatial polarization that characterizes the dwellings in the African leading megacity of Lagos. Data were collected through an extensive housing survey carried out on 1,485 household residences in 56 wards within 12 administrative units in Lagos megacity. The spatial dimension of residential density in the city generates three unique residential patterns which are low residential density (LRD, medium residential density (MRD, and high residential density (HRD areas. Descriptive and multivariate inferential statistics were used to render explanations for the spatial variations in the residential quality variables in the study area. Findings indicated that a clear difference exists in the residential quality within the three residential density areas of Lagos. High correlations exist among the residential quality indicators and housing type. The principal component analysis shows that residential polarizations that occur in the LRD, MRD, and HRD are based on the location, dwelling facility, interior and exterior quality, neighborhood integrity, social bond, barrier to entry, and security. The practical implications of residential polarizations along the residential density areas are explicitly expressed.

Modeling and simulation of a residential micro-CHP system based on HT-PEMFC technology

DEFF Research Database (Denmark)

Arsalis, Alexandros; Nielsen, Mads Pagh; Kær, Søren Knudsen

2009-01-01

Combined-heat-and-power (CHP) technology is a well known and proved method to produce simultaneously power and heat at high efficiencies. This can be further improved by the introduction of a novel micro-CHP residential system based on High Temperature-Proton Exchange Membrane Fuel Cell (HT-PEMFC......). The HT-PEMFC (based on PBI-membrane technology) operates at temperatures near 200oC, and this can be an ideal match for cogeneration residential systems. The proposed system provides electric power, hot water, and space heating for a typical household (1-5 kWe, 5-10 kWth). The micro-CHP system...

Personal exposures to VOC in the upper end of the distribution—relationships to indoor, outdoor and workplace concentrations

Science.gov (United States)

Edwards, Rufus D.; Schweizer, Christian; Jantunen, Matti; Lai, Hak Kan; Bayer-Oglesby, Lucy; Katsouyanni, Klea; Nieuwenhuijsen, Mark; Saarela, Kristiina; Sram, Radim; Künzli, Nino

Evaluation of relationships between median residential indoor, indoor workplace and population exposures may obscure potential strategies for exposure reduction. Evaluation of participants with personal exposures above median levels in the EXPOLIS study in Athens, Helsinki, Oxford and Prague illustrated that these participants frequently showed a different relationship to indoor and workplace levels than that shown by the population median. Thus, prioritization of environments for control measures based on median exposures may exclude important areas where effectively focused control measures are possible, and may therefore have little impact on the highest and most harmful exposures. Further, personal exposures at the upper end of the distribution may exceed the US EPA inhalation reference concentration (Rfc), illustrated here using hexane, naphthalene and benzene. For example upper 90th percentile personal exposures to benzene in Athens and Prague were 64 and 27 μg m -3 with peak exposures of 217 and 38 μg m -3, respectively for non-ETS exposed participants relative to an Rfc of 30 μg m -3. Strategies to reduce exposures to individual compounds, therefore, may benefit from focus on the high end of the distribution to identify activities and behaviors that result in elevated exposures. Control strategies targeting activities that lead to exposures in the upper end of the distribution would reduce the variability associated with population median values by bringing the upper end of the exposure distribution closer to median values. Thus, compliance with health-based standards would be more protective of the higher exposed fraction of the population, in whom health effects would be more expected.

Thermal and Daylighting Performance of Energy-Efficient Windows in Highly Glazed Residential Buildings: Case Study in Korea

Directory of Open Access Journals (Sweden)

Chang Heon Cheong

2014-10-01

Full Text Available Cooling load in highly glazed residential building can be excessively large due to uncontrolled solar energy entering the indoor space. This study focuses on the cooling load reduction and changes in the daylighting properties via the application of a double window system (DWS with shading with various surface reflectivities in highly glazed residential buildings. Evaluation of thermal and daylighting performances is carried out using simulation tools. The reductions in cooling load and energy cost through the use of DWS are evaluated through a comparative simulation considering conventional windows: a single window and a double window. Three variables of window types, natural ventilation, and shading reflectivity are reflected in the study. According to our results, implementation of DWS reduced cooling load by 43%–61%. Electricity cost during the cooling period was reduced by a maximum of 24%. However, a shading device setting that prioritizes effective cooling load reduction can greatly decrease the daylighting factor and luminance level of indoor space. A DWS implementing shading device with highly reflective at all surfaces is appropriate option for the more comfortable thermal and visual environment, while a shading device with low reflectivity at rear of the surface can contribute an additional 4% cooling load reduction.

Indoor Chemistry

DEFF Research Database (Denmark)

Weschler, Charles J.; Carslaw, Nicola

2018-01-01

This review aims to encapsulate the importance, ubiquity, and complexity of indoor chemistry. We discuss the many sources of indoor air pollutants and summarize their chemical reactions in the air and on surfaces. We also summarize some of the known impacts of human occupants, who act as sources...... and sinks of indoor chemicals, and whose activities (e.g., cooking, cleaning, smoking) can lead to extremely high pollutant concentrations. As we begin to use increasingly sensitive and selective instrumentation indoors, we are learning more about chemistry in this relatively understudied environment....

NFC Internal: An Indoor Navigation System

Directory of Open Access Journals (Sweden)

Busra Ozdenizci

2015-03-01

Full Text Available Indoor navigation systems have recently become a popular research field due to the lack of GPS signals indoors. Several indoors navigation systems have already been proposed in order to eliminate deficiencies; however each of them has several technical and usability limitations. In this study, we propose NFC Internal, a Near Field Communication (NFC-based indoor navigation system, which enables users to navigate through a building or a complex by enabling a simple location update, simply by touching NFC tags those are spread around and orient users to the destination. In this paper, we initially present the system requirements, give the design details and study the viability of NFC Internal with a prototype application and a case study. Moreover, we evaluate the performance of the system and compare it with existing indoor navigation systems. It is seen that NFC Internal has considerable advantages and significant contributions to existing indoor navigation systems in terms of security and privacy, cost, performance, robustness, complexity, user preference and commercial availability.

Indoor Environment Program

International Nuclear Information System (INIS)

Daisey, J.M.

1993-06-01

This paper reports progress during the year 1992 in the Indoor Environment Program in the Energy and Environment Division of Lawrence Berkeley Laboratory. Studies in the following areas are reported: energy performance and ventilation in buildings; physical and chemical characterization of indoor air pollutants; indoor radon; indoor air quality; exposure to indoor air pollutants and risk analysis. Pollutants of particular interest include: radon; volatile, semi-volatile and particulate organic compounds; and combustion emissions including environmental tobacco smoke, carbon monoxide, and nitrogen oxides

Indoor Modelling from Slam-Based Laser Scanner: Door Detection to Envelope Reconstruction

Science.gov (United States)

Díaz-Vilariño, L.; Verbree, E.; Zlatanova, S.; Diakité, A.

2017-09-01

Updated and detailed indoor models are being increasingly demanded for various applications such as emergency management or navigational assistance. The consolidation of new portable and mobile acquisition systems has led to a higher availability of 3D point cloud data from indoors. In this work, we explore the combined use of point clouds and trajectories from SLAM-based laser scanner to automate the reconstruction of building indoors. The methodology starts by door detection, since doors represent transitions from one indoor space to other, which constitutes an initial approach about the global configuration of the point cloud into building rooms. For this purpose, the trajectory is used to create a vertical point cloud profile in which doors are detected as local minimum of vertical distances. As point cloud and trajectory are related by time stamp, this feature is used to subdivide the point cloud into subspaces according to the location of the doors. The correspondence between subspaces and building rooms is not unambiguous. One subspace always corresponds to one room, but one room is not necessarily depicted by just one subspace, for example, in case of a room containing several doors and in which the acquisition is performed in a discontinue way. The labelling problem is formulated as combinatorial approach solved as a minimum energy optimization. Once the point cloud is subdivided into building rooms, envelop (conformed by walls, ceilings and floors) is reconstructed for each space. The connectivity between spaces is included by adding the previously detected doors to the reconstructed model. The methodology is tested in a real case study.

A Hybrid 3D Indoor Space Model

Directory of Open Access Journals (Sweden)

A. Jamali

2016-10-01

Full Text Available GIS integrates spatial information and spatial analysis. An important example of such integration is for emergency response which requires route planning inside and outside of a building. Route planning requires detailed information related to indoor and outdoor environment. Indoor navigation network models including Geometric Network Model (GNM, Navigable Space Model, sub-division model and regular-grid model lack indoor data sources and abstraction methods. In this paper, a hybrid indoor space model is proposed. In the proposed method, 3D modeling of indoor navigation network is based on surveying control points and it is less dependent on the 3D geometrical building model. This research proposes a method of indoor space modeling for the buildings which do not have proper 2D/3D geometrical models or they lack semantic or topological information. The proposed hybrid model consists of topological, geometrical and semantical space.

Vision-Based System for Human Detection and Tracking in Indoor Environment

OpenAIRE

Benezeth , Yannick; Emile , Bruno; Laurent , Hélène; Rosenberger , Christophe

2010-01-01

International audience; In this paper, we propose a vision-based system for human detection and tracking in indoor environment using a static camera. The proposed method is based on object recognition in still images combined with methods using temporal information from the video. Doing that, we improve the performance of the overall system and reduce the task complexity. We first use background subtraction to limit the search space of the classifier. The segmentation is realized by modeling ...

Relation between residential radon concentrations and housing characteristics. The Cracow study

International Nuclear Information System (INIS)

Jedrychowski, W.; Flak, E.; Wesolowski, J.; Liu Kaishen

1995-01-01

The survey on indoor radon exposure was undertaken to explain whether the excess in lung cancer deaths in the Cracow city center may be attributed to this particular exposure. A total of 310 detectors was placed in households randomly chosen from three homogeneous strata of residential buildings. The first stratum included houses in the old city center constructed predominantly from stone bricks. The second stratum covered the city area with big apartment condominiums built from concrete blocks. The third stratum consisted of single family houses located in a suburban area. From each of these residency strata a random sample of an equal number of households was chosen, and the radon detectors were placed in households located at various levels of the buildings. The three-month radon sampling data were used to determine the distribution of various levels of radon in the households. In the measurement of radon exposure, Landauer α-track samplers were used. The data collected show that the type of building was the best single predictor of indoor radon concentrations. Other variables found to be associated significantly with indoor concentrations were the household level in the building and the house age. In general, residences with concrete slabs and dwellings with rarely-opened windows were found to have slightly higher radon concentrations. (author) 2 tabs., 15 refs

THE EXTRACTION OF INDOOR BUILDING INFORMATION FROM BIM TO OGC INDOORGML

Directory of Open Access Journals (Sweden)

T.-A. Teo

2017-07-01

Full Text Available Indoor Spatial Data Infrastructure (indoor-SDI is an important SDI for geosptial analysis and location-based services. Building Information Model (BIM has high degree of details in geometric and semantic information for building. This study proposed direct conversion schemes to extract indoor building information from BIM to OGC IndoorGML. The major steps of the research include (1 topological conversion from building model into indoor network model; and (2 generation of IndoorGML. The topological conversion is a major process of generating and mapping nodes and edges from IFC to indoorGML. Node represents every space (e.g. IfcSpace and objects (e.g. IfcDoor in the building while edge shows the relationships between nodes. According to the definition of IndoorGML, the topological model in the dual space is also represented as a set of nodes and edges. These definitions of IndoorGML are the same as in the indoor network. Therefore, we can extract the necessary data in the indoor network and easily convert them into IndoorGML based on IndoorGML Schema. The experiment utilized a real BIM model to examine the proposed method. The experimental results indicated that the 3D indoor model (i.e. IndoorGML model can be automatically imported from IFC model by the proposed procedure. In addition, the geometric and attribute of building elements are completely and correctly converted from BIM to indoor-SDI.

Monocular Vision SLAM for Indoor Aerial Vehicles

Directory of Open Access Journals (Sweden)

Koray Çelik

2013-01-01

Full Text Available This paper presents a novel indoor navigation and ranging strategy via monocular camera. By exploiting the architectural orthogonality of the indoor environments, we introduce a new method to estimate range and vehicle states from a monocular camera for vision-based SLAM. The navigation strategy assumes an indoor or indoor-like manmade environment whose layout is previously unknown, GPS-denied, representable via energy based feature points, and straight architectural lines. We experimentally validate the proposed algorithms on a fully self-contained microaerial vehicle (MAV with sophisticated on-board image processing and SLAM capabilities. Building and enabling such a small aerial vehicle to fly in tight corridors is a significant technological challenge, especially in the absence of GPS signals and with limited sensing options. Experimental results show that the system is only limited by the capabilities of the camera and environmental entropy.

Advanced Controls for Residential Whole-House Ventilation Systems

Energy Technology Data Exchange (ETDEWEB)

Turner, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sherman, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2014-08-01

Whole-house ventilation systems are becoming commonplace in new construction, remodeling/renovation, and weatherization projects, driven by combinations of specific requirements for indoor air quality (IAQ), health and compliance with standards, such as ASHRAE 62.2. Ventilation systems incur an energy penalty on the home via fan power used to drive the airflow, and the additional space-conditioning load associated with heating or cooling the ventilation air. Finding a balance between IAQ and energy use is important if homes are to be adequately ventilated while not increasing the energy burden. This study used computer simulations to examine RIVEC the Residential Integrated Ventilation Controller - a prototype ventilation controller that aims to deliver whole-house ventilation rates that comply with ventilation standards, for the minimum use of energy. Four different whole-house ventilation systems were simulated, both with and without RIVEC, so that the energy and IAQ results could be compared. Simulations were conducted for 13 US climate zones, three house designs, and three envelope leakage values. The results showed that the RIVEC controller could typically return ventilation energy savings greater than 40percent without compromising long-term chronic or short-term acute exposures to relevant indoor contaminants. Critical and average peak power loads were also reduced as a consequence of using RIVEC.

An Indoor Positioning System Based on Wearables for Ambient-Assisted Living.

Science.gov (United States)

Belmonte-Fernández, Óscar; Puertas-Cabedo, Adrian; Torres-Sospedra, Joaquín; Montoliu-Colás, Raúl; Trilles-Oliver, Sergi

2016-12-25

The urban population is growing at such a rate that by 2050 it is estimated that 84% of the world's population will live in cities, with flats being the most common living place. Moreover, WiFi technology is present in most developed country urban areas, with a quick growth in developing countries. New Ambient-Assisted Living applications will be developed in the near future having user positioning as ground technology: elderly tele-care, energy consumption, security and the like are strongly based on indoor positioning information. We present an Indoor Positioning System for wearable devices based on WiFi fingerprinting. Smart-watch wearable devices are used to acquire the WiFi strength signals of the surrounding Wireless Access Points used to build an ensemble of Machine Learning classification algorithms. Once built, the ensemble algorithm is used to locate a user based on the WiFi strength signals provided by the wearable device. Experimental results for five different urban flats are reported, showing that the system is robust and reliable enough for locating a user at room level into his/her home. Another interesting characteristic of the presented system is that it does not require deployment of any infrastructure, and it is unobtrusive, the only device required for it to work is a smart-watch.

Correlation analysis of lung cancer and urban spatial factor: based on survey in Shanghai.

Science.gov (United States)

Wang, Lan; Zhao, Xiaojing; Xu, Wangyue; Tang, Jian; Jiang, Xiji

2016-09-01

The density of particulate matter (PM) in mega-cities in China such as Beijing and Shanghai has exceeded basic standards for health in recent years. Human exposure to PMs has been identified as traceable and controllable factor among all complicated risk factors for lung cancer. While the improvement of air quality needs tremendous efforts and time, certain revision of PM's density might happen associated with the adjustment of built environment. It is also proved that urban built environment is directly relevant to respiratory disease. Studies have respectively explored the indoor and outdoor factors on respiratory diseases. More comprehensive spatial factors need to be analyzed to understand the cumulative effect of built environment upon respiratory system. This interdisciplinary study examines the impact of both indoor (including age of housing, interval after decoration, indoor humidity etc.) and outdoor spatial factors (including density, parking, green spaces etc.) on lung cancer. A survey of lung cancer patients and a control group has been conducted in 2014 and 2015. A total of 472 interviewees are randomly selected within a pool of local residents who have resided in Shanghai for more than 5 years. Data are collected including their socio-demographic factors, lifestyle factors, and external and internal residential area factors. Regression models are established based on collected data to analyze the associations between lung cancer and urban spatial factors. Regression models illustrate that lung cancer presents significantly associated with a number of spatial factors. Significant outdoor spatial factors include external traffic volume (P=0.003), main plant type (P=0.035 for trees) of internal green space, internal water body (P=0.027) and land use of surrounding blocks (P=0.005 for residential areas of 7-9 floors, P=0.000 for residential areas of 4-6 floors, P=0.006 for business/commercial areas over 10 floors, P=0.005 for business/commercial areas of

Towards a Sign-Based Indoor Navigation System for People with Visual Impairments.

Science.gov (United States)

Rituerto, Alejandro; Fusco, Giovanni; Coughlan, James M

2016-10-01

Navigation is a challenging task for many travelers with visual impairments. While a variety of GPS-enabled tools can provide wayfinding assistance in outdoor settings, GPS provides no useful localization information indoors. A variety of indoor navigation tools are being developed, but most of them require potentially costly physical infrastructure to be installed and maintained, or else the creation of detailed visual models of the environment. We report development of a new smartphone-based navigation aid, which combines inertial sensing, computer vision and floor plan information to estimate the user's location with no additional physical infrastructure and requiring only the locations of signs relative to the floor plan. A formative study was conducted with three blind volunteer participants demonstrating the feasibility of the approach and highlighting the areas needing improvement.

Research review: Indoor air quality control techniques

International Nuclear Information System (INIS)

Fisk, W.J.

1986-10-01

Techniques for controlling the concentration of radon, formaldehyde, and combustion products in the indoor air are reviewed. The most effective techniques, which are generally based on limiting or reducing indoor pollutant source strengths, can decrease indoor pollutant concentrations by a factor of 3 to 10. Unless the initial ventilation rate is unusually low, it is difficult to reduce indoor pollutant concentrations more than approximately 50% by increasing the ventilation rate of an entire building. However, the efficiency of indoor pollutant control by ventilation can be enhanced through the use of local exhaust ventilation near concentrated sources of pollutants, by minimizing short circuiting of air from supply to exhaust when pollutant sources are dispersed and, in some situations, by promoting a displacement flow of air and pollutants toward the exhaust. Active air cleaning is also examined briefly. Filtration and electrostatic air cleaning for removal of particles from the indoor air are the most practical and effective currently available techniques of air cleaning. 49 refs., 7 figs

Indoor air pollution: a public health perspective

International Nuclear Information System (INIS)

Spengler, J.D.; Sexton, K.

1983-01-01

Although official efforts to control air pollution have traditionally focused on outdoor air, it is now apparent that elevated contaminant concentrations are common inside some private and public buildings. Concerns about potential public health problems due to indoor air pollution are based on evidence that urban residents typically spend more than 90 percent of their time indoors, concentrations of some contaminants are higher indoors than outdoors, and for some pollutants personal exposures are not characterized adequately by outdoor measurements. Among the more important indoor contaminants associated with health or irritation effects are passive tobacco smoke, radon decay products, carbon monoxide, nitrogen dioxide, formaldehyde, asbestos fibers, microorganisms, and aeroallergens. Efforts to assess health risks associated with indoor air pollution are limited by insufficient information about the number of people exposed, the pattern and severity of exposures, and the health consequences of exposures. An overall strategy should be developed to investigate indoor exposures, health effects, control options, and public policy alternatives

Life-cycle energy of residential buildings in China

International Nuclear Information System (INIS)

Chang, Yuan; Ries, Robert J.; Wang, Yaowu

2013-01-01

In the context of rapid urbanization and new construction in rural China, residential building energy consumption has the potential to increase with the expected increase in demand. A process-based hybrid life-cycle assessment model is used to quantify the life-cycle energy use for both urban and rural residential buildings in China and determine the energy use characteristics of each life cycle phase. An input–output model for the pre-use phases is based on 2007 Chinese economic benchmark data. A process-based life-cycle assessment model for estimating the operation and demolition phases uses historical energy-intensity data. Results show that operation energy in both urban and rural residential buildings is dominant and varies from 75% to 86% of life cycle energy respectively. Gaps in living standards as well as differences in building structure and materials result in a life-cycle energy intensity of urban residential buildings that is 20% higher than that of rural residential buildings. The life-cycle energy of urban residential buildings is most sensitive to the reduction of operational energy intensity excluding heating energy which depends on both the occupants' energy-saving behavior as well as the performance of the building itself. -- Highlights: •We developed a hybrid LCA model to quantify the life-cycle energy for urban and rural residential buildings in China. •Operation energy in urban and rural residential buildings is dominant, varying from 75% to 86% of life cycle energy respectively. •Compared with rural residential buildings, the life-cycle energy intensity of urban residential buildings is 20% higher. •The life-cycle energy of urban residential buildings is most sensitive to the reduction of daily activity energy

Indoor Trajectory Tracking Scheme Based on Delaunay Triangulation and Heuristic Information in Wireless Sensor Networks.

Science.gov (United States)

Qin, Junping; Sun, Shiwen; Deng, Qingxu; Liu, Limin; Tian, Yonghong

2017-06-02

Object tracking and detection is one of the most significant research areas for wireless sensor networks. Existing indoor trajectory tracking schemes in wireless sensor networks are based on continuous localization and moving object data mining. Indoor trajectory tracking based on the received signal strength indicator ( RSSI ) has received increased attention because it has low cost and requires no special infrastructure. However, RSSI tracking introduces uncertainty because of the inaccuracies of measurement instruments and the irregularities (unstable, multipath, diffraction) of wireless signal transmissions in indoor environments. Heuristic information includes some key factors for trajectory tracking procedures. This paper proposes a novel trajectory tracking scheme based on Delaunay triangulation and heuristic information (TTDH). In this scheme, the entire field is divided into a series of triangular regions. The common side of adjacent triangular regions is regarded as a regional boundary. Our scheme detects heuristic information related to a moving object's trajectory, including boundaries and triangular regions. Then, the trajectory is formed by means of a dynamic time-warping position-fingerprint-matching algorithm with heuristic information constraints. Field experiments show that the average error distance of our scheme is less than 1.5 m, and that error does not accumulate among the regions.

Healthy indoors : achieving healthy indoor environments in Canada : Final report

International Nuclear Information System (INIS)

Anon

2002-01-01

A large proportion of the lives of Canadians is spent indoors, whether in vehicles, restaurants, shopping malls, offices or houses. The health of people working and living in those indoor settings might be damaged a a result, despite best efforts. Indoor pollution has been identified as one of the most serious risks to human health, according to numerous leading authorities, among them the American Lung Association, the United States Environmental Protection Agency, the Canada Mortgage and Housing Corporation (CMHC). A large number of cancer deaths are attributed to indoor pollution each year in the United States, as well as respiratory health problems. A causal link between certain indoor exposures and the development and provocation of asthma was established recently in a report on asthma and indoor air quality published by the National Academy of Sciences/Institute of Medicine. Exposure to indoor pollutants has also resulted in thousands of children experiencing elevated blood lead levels. Not enough attention is paid in Canada to pollution in buildings by government agencies, corporations and other non-governmental organizations and citizens. Not much seems to have changed in the past thirty years. An ambitious strategy by Pollution Probe was described in this document, listing the initial goals and measures required to achieve those goals. The creation of Healthy Indoors Partnership (HIP) was proposed to regroup all the stakeholders under the same umbrella. refs., tabs

A combined analysis of North American case-control studies of residential radon and lung cancer.

Science.gov (United States)

Krewski, Daniel; Lubin, Jay H; Zielinski, Jan M; Alavanja, Michael; Catalan, Vanessa S; Field, R William; Klotz, Judith B; Létourneau, Ernest G; Lynch, Charles F; Lyon, Joseph L; Sandler, Dale P; Schoenberg, Janet B; Steck, Daniel J; Stolwijk, Jan A; Weinberg, Clarice; Wilcox, Homer B

2006-04-01

Cohort studies have consistently shown underground miners exposed to high levels of radon to be at excess risk of lung cancer, and extrapolations based on those results indicate that residential radon may be responsible for nearly 10-15% of all lung cancer deaths per year in the United States. However, case-control studies of residential radon and lung cancer have provided ambiguous evidence of radon lung cancer risks. Regardless, alpha-particle emissions from the short-lived radioactive radon decay products can damage cellular DNA. The possibility that a demonstrated lung carcinogen may be present in large numbers of homes raises a serious public health concern. Thus, a systematic analysis of pooled data from all North American residential radon studies was undertaken to provide a more direct characterization of the public health risk posed by prolonged radon exposure. To evaluate the risk associated with prolonged residential radon exposure, a combined analysis of the primary data from seven large scale case-control studies of residential radon and lung cancer risk was conducted. The combined data set included a total of 4081 cases and 5281 controls, representing the largest aggregation of data on residential radon and lung cancer conducted to date. Residential radon concentrations were determined primarily by a-track detectors placed in the living areas of homes of the study subjects in order to obtain an integrated 1-yr average radon concentration in indoor air. Conditional likelihood regression was used to estimate the excess risk of lung cancer due to residential radon exposure, with adjustment for attained age, sex, study, smoking factors, residential mobility, and completeness of radon measurements. Although the main analyses were based on the combined data set as a whole, we also considered subsets of the data considered to have more accurate radon dosimetry. This included a subset of the data involving 3662 cases and 4966 controls with a-track radon

Collecting data for indoor mapping of the University of Münster via a location based game

OpenAIRE

Naranjo Zolotov, Mijail

2015-01-01

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies. Nowadays the collection of spatial indoor mapping data presents a big challenge for both science and industry because there is not a cost-effective method yet for it as it is for outdoor mapping. Research is pointing out to crowdsourcing as means of address the challenge of massive indoor mapping based on the principle that people should be the main ...

An Innovative Gateway for Indoor Positioning

Directory of Open Access Journals (Sweden)

Marias Giannis F

2006-01-01

Full Text Available Enabling the pervasive paradigm requires the incorporation of location information. Retrieving location data has been a field of ongoing research for both the outdoor and indoor wireless systems. The results in the cellular scenario are already mature and location architectures have been standardized. Recent research is ongoing for indoor-positioning mechanisms, resulting in implementations that vary. A platform that enables the deployment of location-based services in heterogeneous indoor and WLAN-based communication systems will address difficulties in cooperating with different positioning systems. For that purpose, we have designed a novel entity, called Gateway WLAN Location Center (GWLC, which hides the heterogeneous functions of the indoor positioning architectures, incorporating a unified framework for retrieving location data of users and objects. The GWLC platform has been designed to meet objectives such as modularity, scalability, as well as portability, and to facilitate open interfaces. In this contribution, we elaborate on the design principles and the functionality of GWLC. We also provide performance results, obtained through real experiments.

Measure Guideline: Ventilation Guidance for Residential High-Performance New Construction - Multifamily

Energy Technology Data Exchange (ETDEWEB)

Lstiburek, Joseph [Building Science Corporation, Westford, MA (United States)

2017-01-01

The measure guideline provides ventilation guidance for residential high performance multifamily construction that incorporates the requirements of the ASHRAE 62.2 ventilation and indoor air quality standard. The measure guideline focus is on the decision criteria for weighing cost and performance of various ventilation systems. The measure guideline is intended for contractors, builders, developers, designers and building code officials. The guide may also be helpful to building owners wishing to learn more about ventilation strategies available for their buildings. The measure guideline includes specific design and installation instructions for the most cost effective and performance effective solutions for ventilation in multifamily units that satisfies the requirements of ASHRAE 62.2-2016.

INDOOR MODELLING FROM SLAM-BASED LASER SCANNER: DOOR DETECTION TO ENVELOPE RECONSTRUCTION

Directory of Open Access Journals (Sweden)

L. Díaz-Vilariño

2017-09-01

Full Text Available Updated and detailed indoor models are being increasingly demanded for various applications such as emergency management or navigational assistance. The consolidation of new portable and mobile acquisition systems has led to a higher availability of 3D point cloud data from indoors. In this work, we explore the combined use of point clouds and trajectories from SLAM-based laser scanner to automate the reconstruction of building indoors. The methodology starts by door detection, since doors represent transitions from one indoor space to other, which constitutes an initial approach about the global configuration of the point cloud into building rooms. For this purpose, the trajectory is used to create a vertical point cloud profile in which doors are detected as local minimum of vertical distances. As point cloud and trajectory are related by time stamp, this feature is used to subdivide the point cloud into subspaces according to the location of the doors. The correspondence between subspaces and building rooms is not unambiguous. One subspace always corresponds to one room, but one room is not necessarily depicted by just one subspace, for example, in case of a room containing several doors and in which the acquisition is performed in a discontinue way. The labelling problem is formulated as combinatorial approach solved as a minimum energy optimization. Once the point cloud is subdivided into building rooms, envelop (conformed by walls, ceilings and floors is reconstructed for each space. The connectivity between spaces is included by adding the previously detected doors to the reconstructed model. The methodology is tested in a real case study.

A Foundation for Efficient Indoor Distance-Aware Query Processing

DEFF Research Database (Denmark)

Lu, Hua; Cao, Xin; Jensen, Christian Søndergaard

2012-01-01

model that integrates indoor distance seamlessly. To enable the use of the model as a foundation for query processing, we develop accompanying, efficient algorithms that compute indoor distances for different indoor entities like doors as well as locations. We also propose an indexing framework......Indoor spaces accommodate large numbers of spatial objects, e.g., points of interest (POIs), and moving populations. A variety of services, e.g., location-based services and security control, are relevant to indoor spaces. Such services can be improved substantially if they are capable of utilizing...... that accommodates indoor distances that are pre-computed using the proposed algorithms. On top of this foundation, we develop efficient algorithms for typical indoor, distance-aware queries. The results of an extensive experimental evaluation demonstrate the efficacy of the proposals....

Providing better indoor environmental quality brings economicbenefits

Energy Technology Data Exchange (ETDEWEB)

Fisk, William; Seppanen, Olli

2007-06-01

This paper summarizes the current scientific evidence that improved indoor environmental quality can improve work performance and health. The review indicates that work and school work performance is affected by indoor temperature and ventilation rate. Pollutant source removal can sometimes improve work performance. Based on formal statistical analyses of existing research results, quantitative relationships are provided for the linkages of work performance with indoor temperature and outdoor air ventilation rate. The review also indicates that improved health and related financial savings are obtainable from reduced indoor tobacco smoking, prevention and remediation of building dampness, and increased ventilation. Example cost-benefit analyses indicate that many measures to improve indoor temperature control and increase ventilation rates will be highly cost effective, with benefit-cost ratios as high as 80 and annual economic benefits as high as $700 per person.

Older adults’ home- and community-based care service use and residential transitions: a longitudinal study

Directory of Open Access Journals (Sweden)

Chen Ya-Mei

2012-08-01

Full Text Available Abstract Background As Home-and Community-Based Services (HCBS, such as skilled nursing services or personal care services, have become increasingly available, it has become clear that older adults transit through different residential statuses over time. Older adults may transit through different residential statuses as the various services meet their needs. The purpose of this exploratory study was to better understand the interplay between community-dwelling older adults’ use of home- and community-based services and their residential transitions. Methods The study compared HCBS service-use patterns and residential transitions of 3,085 older adults from the Second Longitudinal Study of Aging. Based on older adults’ residential status at the three follow-up interviews, four residential transitions were tracked: (1 Community-Community-Community (CCC: Resided in community during the entire study period; (2 Community-Institution-Community (CIC: Resided in community at T1, had lived in an institution at some time between T1 and T2, then had returned to community by T3; (3 Community-Community-Institution (CCI: Resided in community between at T1, and betweenT1 and T2, including at T2, but had used institutional services between T2 and T3; (4 Community-Institution-Institution (CII: Resided in community at T1 but in an institution at some time between T1 and T2, and at some time between T2 and T3.. Results Older adults’ use of nondiscretionary and discretionary services differed significantly among the four groups, and the patterns of HCBS use among these groups were also different. Older adults’ use of nondiscretionary services, such as skilled nursing care, may help them to return to communities from institutions. Personal care services (PCS and senior center services may be the key to either support elders to stay in communities longer or help elders to return to their communities from institutions. Different combinations of PCS with other

Current implications of past DDT indoor spraying in Oman.

Science.gov (United States)

Booij, Petra; Holoubek, Ivan; Klánová, Jana; Kohoutek, Jiří; Dvorská, Alice; Magulová, Katarína; Al-Zadjali, Said; Čupr, Pavel

2016-04-15

In Oman, DDT was sprayed indoors during an intensive malaria eradication program between 1976 and 1992. DDT can remain for years after spraying and is associated with potential health risk. This raises the concern for human exposure in areas where DDT was used for indoor spraying. Twelve houses in three regions with a different history of DDT indoor spraying were chosen for a sampling campaign in 2005 to determine p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and p,p'-dichlorodiphenyldichloroethane (p,p'-DDD) levels in indoor air, dust, and outdoor soil. Although DDT was only sprayed indoor, p,p'-DDT, p,p'-DDE and p,p'-DDD were also found in outdoor soil. The results indicate that release and exposure continue for years after cessation of spraying. The predicted cancer risk based on concentrations determined in 2005, indicate that there was still a significant cancer risk up to 13 to 16years after indoor DDT spraying. A novel approach, based on region-specific half-lives, was used to predict concentrations in 2015 and showed that more than 21years after spraying, cancer risk for exposure to indoor air, dust, and outdoor soil are acceptable in Oman for adults and young children. The model can be used for other locations and countries to predict prospective exposure of contaminants based on indoor experimental measurements and knowledge about the spraying time-schedule to extrapolate region-specific half-lives and predict effects on the human population years after spraying. Copyright © 2015 Elsevier B.V. All rights reserved.

Scopulariopsis and scopulariopsis-like species from indoor environments

Directory of Open Access Journals (Sweden)

J.H.C. Woudenberg

2017-09-01

Full Text Available Scopulariopsis-like species are often reported from the indoor environment, as well as from clinical samples. The lack of type isolates and thorough phylogenetic studies in the Microascaceae hampered the correct identification of these isolates. Based on recent phylogenetic studies, which resulted in multiple name changes, the aim is to molecularly identify the Scopulariopsis and scopulariopsis-like species which occur in the indoor environment and give an overview of the current species in these genera and their habitats. Strains from the CBS culture collection were supplemented with almost 80 indoor strains of which the internal transcribed spacer 1 and 2 and intervening 5.8S nrDNA (ITS, beta-tubulin (tub2 and translation elongation factor 1-alpha (tef1 gene regions were sequenced for phylogenetic inference. The multi-gene phylogenies recognise 33 Microascus species and 12 Scopulariopsis species and showed that the recently established genus Fuscoannellis, typified by Scopulariopsis carbonaria, should be synonymized with the genus Yunnania. Seven new Microascus species, four new Scopulariopsis species, and one new Yunnania species, are described, and a new name in Microascus and two new name combinations (one in Microascus, and one in Yunnania are proposed. In the indoor environment 14 Microascus species and three Scopulariopsis species were found. Scopulariopsis brevicaulis (22 indoor isolates and Microascus melanosporus (19 indoor isolates are the most common indoor species, in number of isolates, followed by M. paisii (8 indoor isolates and S. candida (7 indoor isolates. A genus phylogeny based on the ITS, tef1 and the large subunit 28S nrDNA (LSU of the type or representative isolates of all here recognised species is provided depicting all species habitats. No correlation between phylogenetic relationship and habitat preference could be observed. Ten species which are found indoor are also found in relation with human-derived samples. A

Indoor air quality

DEFF Research Database (Denmark)

Jensen, Trine Susanne; Recevska, Ieva

 The objective of the 35th specific agreement is to provide support to the EEA activities in Environment and Health (E&H) on the topic of indoor air quality. The specific objectives have been to provide an overview of indoor air related projects in EU and indoor air related policies as well...... as idenfiying "good practices" to reduce health impact of indoor air exposure and suggest areas for future improvements....

The role of the U.S. Department of Energy in indoor air quality and building ventilation policy development

Energy Technology Data Exchange (ETDEWEB)

Traynor, G.W. [Lawrence Berkeley Lab., Berkeley, CA (United States). Indoor Environment Program; Talbott, J.M. [U.S. Dept. of Energy, Washington, DC (United States). Office of Building Technologies; Moses, D.O. [U.S. Dept. of Energy, Washington, DC (United States). Office of Environmental Analysis

1993-12-31

Building ventilation consumes about 5.8 exajoules of energy each year in the U.S. The annual cost of this-energy, used for commercial building fans (1.6 exajoules/yr) and the heating and cooling of outside air (4.2 exajoules/yr), is about $US 33 billion per year. Energy conservation measures that reduce heating and cooling season ventilation rates 15 to 35 % in commercial and residential buildings can result in a national savings of about 0.6 to 15 exajoules (doll US 3-8 billion) per year assuming no reduction of commercial building fan energy use. The most significant adverse environmental impact of reduced ventilation and infiltration is the potential degradation of the building`s indoor air quality. Potential benefits to the U.S from the implementation of sound indoor air quality and building ventilation reduction policies include reduced building-sector energy consumption; reduced indoor, outdoor, and global pollution; reduced product costs; reduced worker absenteeism; reduced health care costs; reduced litigation; increased worker well-being and absenteeism; reduced health care costs; reduced litigation; increased productivity; and increased product quality and competitiveness. (author)

Gis Based Analysis For Suitability Location Finding In The Residential Development Areas Of Greater Matara Region

Directory of Open Access Journals (Sweden)

H.K.G.M Madurika

2017-02-01

Full Text Available Urban Planning and Land utilization for the Residential is one of crucial factors in high density Cities. Many theories in Planning explain the Residential areas are moving to periphery areas in cities by its commercial development. Martara is one of developing city in Southern Sri Lanka and Residential land value are comparative high in city sub urban areas. In this study it is examined that where is the best locations for residential development in Grater Matara Region by using five criteria. GIS based Multi Criteria Method MCE method have been applied to find the suitable locations. The results of analysis have been shown that there are 5378.99 hectares area suitable within study area and however extremely importance areas only 1.40 hectares accordingly given criteria but very strongly importance and importance category have 1560.51 and 2468.22 respectively.

Methodology developed to make the Quebec indoor radon potential map

International Nuclear Information System (INIS)

Drolet, Jean-Philippe; Martel, Richard; Poulin, Patrick; Dessau, Jean-Claude

2014-01-01

This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas. It was shown that it is possible to determine thresholds for the three criteria that implied statistically significant different levels of radon potential using Kruskal–Wallis one way analyses of variance by ranks. The three discretized radiogeochemical datasets were combined into a total predicted radon potential that sampled 98% of the studied area. The combination process was also based on Kruskal–Wallis one way ANOVA. Four statistically significant different predicted radon potential levels were created: low, medium, high and very high. Respectively 10 and 13% of the dwellings exceed the Canadian radon guideline of 200 Bq/m 3 in low and medium predicted radon potentials. These proportions rise up to 22 and 45% respectively for high and very high predicted radon potentials. This predictive map of indoor radon potential based on the radiogeochemical data was validated using a map of confirmed radon exposure in homes based on the basement radon measurements. It was shown that the map of predicted radon potential based on the radiogeochemical data was reliable to identify radon-prone areas even in zones where no indoor radon measurement exists. - Highlights: • 5 radiogeochemical datasets were used to map the geogenic indoor radon potential. • An indoor radon potential was determined for each

Indexing the Trajectories of Moving Objects in Symbolic Indoor Space

DEFF Research Database (Denmark)

Jensen, Christian Søndergaard; Lu, Hua; Yang, Bin

2009-01-01

. This scenario calls for the indexing of indoor trajectories. Based on an appropriate notion of indoor trajectory and definitions of pertinent types of queries, the paper proposes two R-tree based structures for indexing object trajectories in symbolic indoor space. The RTR-tree represents a trajectory as a set......Indoor spaces accommodate large populations of individuals. With appropriate indoor positioning, e.g., Bluetooth and RFID, in place, large amounts of trajectory data result that may serve as a foundation for a wide variety of applications, e.g., space planning, way finding, and security...... for each index. An empirical performance study suggests that the two indexes are effective, efficient, and robust. The study also elicits the circumstances under which our proposals perform the best....

Wi-Fi/MARG Integration for Indoor Pedestrian Localization.

Science.gov (United States)

Tian, Zengshan; Jin, Yue; Zhou, Mu; Wu, Zipeng; Li, Ze

2016-12-10

With the wide deployment of Wi-Fi networks, Wi-Fi based indoor localization systems that are deployed without any special hardware have caught significant attention and have become a currently practical technology. At the same time, the Magnetic, Angular Rate, and Gravity (MARG) sensors installed in commercial mobile devices can achieve highly-accurate localization in short time. Based on this, we design a novel indoor localization system by using built-in MARG sensors and a Wi-Fi module. The innovative contributions of this paper include the enhanced Pedestrian Dead Reckoning (PDR) and Wi-Fi localization approaches, and an Extended Kalman Particle Filter (EKPF) based fusion algorithm. A new Wi-Fi/MARG indoor localization system, including an Android based mobile client, a Web page for remote control, and a location server, is developed for real-time indoor pedestrian localization. The extensive experimental results show that the proposed system is featured with better localization performance, with the average error 0.85 m, than the one achieved by using the Wi-Fi module or MARG sensors solely.

An Indoor Positioning System Based on Wearables for Ambient-Assisted Living

Directory of Open Access Journals (Sweden)

Óscar Belmonte-Fernández

2016-12-01

Full Text Available The urban population is growing at such a rate that by 2050 it is estimated that 84% of the world’s population will live in cities, with flats being the most common living place. Moreover, WiFi technology is present in most developed country urban areas, with a quick growth in developing countries. New Ambient-Assisted Living applications will be developed in the near future having user positioning as ground technology: elderly tele-care, energy consumption, security and the like are strongly based on indoor positioning information. We present an Indoor Positioning System for wearable devices based on WiFi fingerprinting. Smart-watch wearable devices are used to acquire the WiFi strength signals of the surrounding Wireless Access Points used to build an ensemble of Machine Learning classification algorithms. Once built, the ensemble algorithm is used to locate a user based on the WiFi strength signals provided by the wearable device. Experimental results for five different urban flats are reported, showing that the system is robust and reliable enough for locating a user at room level into his/her home. Another interesting characteristic of the presented system is that it does not require deployment of any infrastructure, and it is unobtrusive, the only device required for it to work is a smart-watch.

iParking: An Intelligent Indoor Location-Based Smartphone Parking Service

OpenAIRE

Liu, Jingbin; Chen, Ruizhi; Chen, Yuwei; Pei, Ling; Chen, Liang

2012-01-01

Indoor positioning technologies have been widely studied with a number of solutions being proposed, yet substantial applications and services are still fairly primitive. Taking advantage of the emerging concept of the connected car, the popularity of smartphones and mobile Internet, and precise indoor locations, this study presents the development of a novel intelligent parking service called iParking. With the iParking service, multiple parties such as users, parking facilities and service p...

Configuring a fuel cell based residential combined heat and power system

Science.gov (United States)

Ahmed, Shabbir; Papadias, Dionissios D.; Ahluwalia, Rajesh K.

2013-11-01

The design and performance of a fuel cell based residential combined heat and power (CHP) system operating on natural gas has been analyzed. The natural gas is first converted to a hydrogen-rich reformate in a steam reformer based fuel processor, and the hydrogen is then electrochemically oxidized in a low temperature polymer electrolyte fuel cell to generate electric power. The heat generated in the fuel cell and the available heat in the exhaust gas is recovered to meet residential needs for hot water and space heating. Two fuel processor configurations have been studied. One of the configurations was explored to quantify the effects of design and operating parameters, which include pressure, temperature, and steam-to-carbon ratio in the fuel processor, and fuel utilization in the fuel cell. The second configuration applied the lessons from the study of the first configuration to increase the CHP efficiency. Results from the two configurations allow a quantitative comparison of the design alternatives. The analyses showed that these systems can operate at electrical efficiencies of ∼46% and combined heat and power efficiencies of ∼90%.

Action dependent heuristic dynamic programming based residential energy scheduling with home energy inter-exchange

International Nuclear Information System (INIS)

Xu, Yancai; Liu, Derong; Wei, Qinglai

2015-01-01

Highlights: • The algorithm is developed in the two-household energy management environment. • We develop the absent energy penalty cost for the first time. • The algorithm has ability to keep adapting in real-time operations. • Its application can lower total costs and achieve better load balancing. - Abstract: Residential energy scheduling is a hot topic nowadays in the background of energy saving and environmental protection worldwide. To achieve this objective, a new residential energy scheduling algorithm is developed for energy management, based on action dependent heuristic dynamic programming. The algorithm works under the circumstance of residential real-time pricing and two adjacent housing units with energy inter-exchange, which can reduce the overall cost and enhance renewable energy efficiency after long-term operation. It is designed to obtain the optimal control policy to manage the directions and amounts of electricity energy flux. The algorithm’s architecture is mainly constructed based on neural networks, denoting the learned characteristics in the linkage of layers. To get close to real situations, many constraints such as maximum charging/discharging power of batteries are taken into account. The absent energy penalty cost is developed for the first time as a part of the performance index function. When the environment changes, the residential energy scheduling algorithm gains new features and keeps adapting in real-time operations. Simulation results show that the developed algorithm is beneficial to energy conversation

Very volatile organic compounds: An understudied class of indoor air pollutants: Keynote: Indoor Air 2014

OpenAIRE

Salthammer, T.

2016-01-01

Very volatile organic compounds (VVOCs), as categorized by the WHO, are an important subgroup of indoor pollutants and cover a wide spectrum of chemical substances. Some VVOCs are components of products commonly used indoors, some result from chemical reactions and some are reactive precursors of secondary products. Nevertheless, there is still no clear and internationally accepted definition of VVOCs. Current approaches are based on the boiling point, and the saturation vapor pressure or ref...

Indoor multipath mitigation

DEFF Research Database (Denmark)

Dragünas, Kostas; Borre, Kai

2010-01-01

There are many applications that require continuous positioning in combined outdoor urban and indoor environments. GNSS has been used for a long time in outdoor environments, while indoor positioning is still a challenging task. One of the major degradations that GNSS receivers experience indoors...

Indoor climate optimization with limited resources

DEFF Research Database (Denmark)

Santos, A.; Gunnarsen, Lars Bo

This report presents experimental data and models for optimisation of the indoor climate parameters temperature, noise, draught and window opening. Results are based on experiments with human subjects performed in climate chambers at University of the Philippines. The report may assist building...... designers to balance attention and resources between the parameters of the indoor climate when resources are less than optimal....

Standards for securing adequate indoor air quality across Europe

DEFF Research Database (Denmark)

Wargocki, Pawel; Carrer, P.; de Oliveira Fernandes, E.

2013-01-01

Background: Inadequate IAQ causes a loss of 2 million healthy life years annually in the EU. Europeans spend typically over 85–90% of their time indoors and the main factors that affect negatively the characteristics of the air they breathe are outdoor air used to ventilate indoor spaces and indoor...... effects of IAQ into different components: exposures to indoor and outdoor air pollutants, association with different morbidities and the way ventilation based approaches could minimise their impact. Disability adjusted life years (DALYs), a common metric to allow comparability of impacts on various types...... and is determined mainly considering the metabolic CO2 production. It is only applicable if all other pollutants meet WHO guidelines for ambient and indoor air quality. If they do not meet these guidelines after applying source control and when air used for ventilation is clean health-based ventilation rate should...

Application of multicriteria decision making methods to air quality in the microenvironments of residential houses in Brisbane, Australia.

Science.gov (United States)

Ayoko, Godwin A; Morawska, Lidia; Kokot, Serge; Gilbert, Dale

2004-05-01

This paper reports the first application of the multicriteria decision making methods, PROMETHEE and GAIA, to indoor and outdoor air quality data. Fourteen residential houses in a suburb of Brisbane, Australia were investigated for 21 air quality-influencing criteria, which included the characteristics of the houses as well as the concentrations of volatile organic compounds, fungi, bacteria, submicrometer, and supermicrometer particles in their indoor and outdoor air samples. Ranking information necessary to select one house in preference to all others and to assess the parameters influencing the differentiation of the houses was found with the aid of PROMETHEE and GAIA. There was no correlation between the rank order of each house and the health complaints of its occupants. Patterns in GAIA plots show that indoor air quality in these houses is strongly dependent on the characteristics of the houses (construction material, distance of the house from a major road, and the presence of an in-built garage). Marked similarities were observed in the patterns obtained when GAIA and factor analysis were applied to the data. This underscores the potential of PROMETHEE and GAIA to provide information that can assist source apportionment and elucidation of effective remedial measures for indoor air pollution.

[Indoor dust as a pathway of human exposure to polybrominated diphenyl ethers (PBDEs)].

Science.gov (United States)

Góralczyk, Katarzyna; Struciński, Paweł; Hernik, Agnieszka; Czaja, Katarzyna; Korcz, Wojciech; Minorczyk, Maria; Ludwicki, Jan K

2012-01-01

The brominated diphenyl ethers (PBDEs) belong to a class of synthetic, additive brominated flame retardants (BFRs). PBDEs are used to reduce the flammability of commercial and household products such as textiles, various plastic polymers, furnishing foam, and electronic equipment. People spend a large percentage of their life-time indoors at home, in offices and cars, etc, providing many opportunities for lengthy exposure to PBDEs from residential settings and commercial products in an indoor environment. In recent time, the foodstuffs, mainly food of animal origin, have been indicated as the main pathway of human exposure to PBDEs. However, many studies have shown that the indoor environment, mainly indoor dust, can be also a significant source of exposure to PBDEs, especially for younger children (toddlers) because of their behavioral patterns, eg. putting fingers, toys, and other items in their mouth. Numerous studies show that the median intakes of PBDEs via dust for adult range from 1.41 to 277 ng x day(-1) is lower than that via food which range from 135 to 333 ng x day-', while the median intake of these compounds via indoor dust for children range from 101 to 404 ng x day(-1) is much higher than via food: 77-190 ng x day(-1). The congener pattern observed in the indoor dust is different to that found in food. The indoor dust is dominated by the congener BDE-209 vs. food where the most dominated congeners are BDE-47 and BDE-99. Human exposure to PBDEs and other brominated flame retardants (BFRs) is widely widespread throughout the world and it depends on a country range of usage, production and legislation concerning these chemicals as well as a citizen's behavior. Generally, human exposure has been found higher in North America than in Europe and Asia. Within European countries the significant highest concentrations in dust have been found in the United Kingdom. It should be noted that many uncertainty factors such as personal habits, dietary preferences

The mobility of U and Th in subduction zone fluids: an indicator of oxygen fugacity and fluid salinity

Science.gov (United States)

Bali, Enikő; Audétat, Andreas; Keppler, Hans

2011-04-01

The solubility of U and Th in aqueous solutions at P-T-conditions relevant for subduction zones was studied by trapping uraninite or thorite saturated fluids as synthetic fluid inclusions in quartz and analyzing their composition by Laser Ablation-ICPMS. Uranium is virtually insoluble in aqueous fluids at Fe-FeO buffer conditions, whereas its solubility increases both with oxygen fugacity and with salinity to 960 ppm at 26.1 kbar, Re-ReO2 buffer conditions and 14.1 wt% NaCl in the fluid. At 26.1 kbar and 800°C, uranium solubility can be reproduced by the equation: log {{U}} = 2.681 + 0.1433log f{{O}}2 + 0.594{{Cl,}} where fO2 is the oxygen fugacity, and Cl is the chlorine content of the fluid in molality. In contrast, Th solubility is generally low (uranium increases strongly both with oxygen fugacity and with salinity. We show that reducing or NaCl-free fluids cannot produce primitive arc magmas with U/Th ratio higher than MORB. However, the dissolution of several wt% of oxidized, saline fluids in arc melts can produce U/Th ratios several times higher than in MORB. We suggest that observed U/Th ratios in arc magmas provide tight constraints on both the salinity and the oxidation state of subduction zone fluids.

Smartphone-Based Indoor Localization with Bluetooth Low Energy Beacons.

Science.gov (United States)

Zhuang, Yuan; Yang, Jun; Li, You; Qi, Longning; El-Sheimy, Naser

2016-04-26

Indoor wireless localization using Bluetooth Low Energy (BLE) beacons has attracted considerable attention after the release of the BLE protocol. In this paper, we propose an algorithm that uses the combination of channel-separate polynomial regression model (PRM), channel-separate fingerprinting (FP), outlier detection and extended Kalman filtering (EKF) for smartphone-based indoor localization with BLE beacons. The proposed algorithm uses FP and PRM to estimate the target's location and the distances between the target and BLE beacons respectively. We compare the performance of distance estimation that uses separate PRM for three advertisement channels (i.e., the separate strategy) with that use an aggregate PRM generated through the combination of information from all channels (i.e., the aggregate strategy). The performance of FP-based location estimation results of the separate strategy and the aggregate strategy are also compared. It was found that the separate strategy can provide higher accuracy; thus, it is preferred to adopt PRM and FP for each BLE advertisement channel separately. Furthermore, to enhance the robustness of the algorithm, a two-level outlier detection mechanism is designed. Distance and location estimates obtained from PRM and FP are passed to the first outlier detection to generate improved distance estimates for the EKF. After the EKF process, the second outlier detection algorithm based on statistical testing is further performed to remove the outliers. The proposed algorithm was evaluated by various field experiments. Results show that the proposed algorithm achieved the accuracy of EKF algorithm and 15.77% more accurate than EKF algorithm. With sparse deployment (1 beacon per 18 m), the proposed algorithm achieves the accuracies of EKF algorithm and 21.41% better than EKF algorithm. Therefore, the proposed algorithm is especially useful to improve the localization accuracy in environments with sparse beacon deployment.

An Indoor Scene Recognition-Based 3D Registration Mechanism for Real-Time AR-GIS Visualization in Mobile Applications

Directory of Open Access Journals (Sweden)

Wei Ma

2018-03-01

Full Text Available Mobile Augmented Reality (MAR systems are becoming ideal platforms for visualization, permitting users to better comprehend and interact with spatial information. Subsequently, this technological development, in turn, has prompted efforts to enhance mechanisms for registering virtual objects in real world contexts. Most existing AR 3D Registration techniques lack the scene recognition capabilities needed to describe accurately the positioning of virtual objects in scenes representing reality. Moreover, the application of such registration methods in indoor AR-GIS systems is further impeded by the limited capacity of these systems to detect the geometry and semantic information in indoor environments. In this paper, we propose a novel method for fusing virtual objects and indoor scenes, based on indoor scene recognition technology. To accomplish scene fusion in AR-GIS, we first detect key points in reference images. Then, we perform interior layout extraction using a Fully Connected Networks (FCN algorithm to acquire layout coordinate points for the tracking targets. We detect and recognize the target scene in a video frame image to track targets and estimate the camera pose. In this method, virtual 3D objects are fused precisely to a real scene, according to the camera pose and the previously extracted layout coordinate points. Our results demonstrate that this approach enables accurate fusion of virtual objects with representations of real world indoor environments. Based on this fusion technique, users can better grasp virtual three-dimensional representations on an AR-GIS platform.

A hierarchical inferential method for indoor scene classification

Directory of Open Access Journals (Sweden)

Jiang Jingzhe

2017-12-01

Full Text Available Indoor scene classification forms a basis for scene interaction for service robots. The task is challenging because the layout and decoration of a scene vary considerably. Previous studies on knowledge-based methods commonly ignore the importance of visual attributes when constructing the knowledge base. These shortcomings restrict the performance of classification. The structure of a semantic hierarchy was proposed to describe similarities of different parts of scenes in a fine-grained way. Besides the commonly used semantic features, visual attributes were also introduced to construct the knowledge base. Inspired by the processes of human cognition and the characteristics of indoor scenes, we proposed an inferential framework based on the Markov logic network. The framework is evaluated on a popular indoor scene dataset, and the experimental results demonstrate its effectiveness.

A View Indoors, Indoor Environment Division's e-Article Series

Science.gov (United States)

The Indoor Environments Division has created partnership with public and private sector entities to help encourage the public to take action to minimize their risk and mitigate indoor air quality problems.

Hidden Markov Model based Mobility Learning for Improving Indoor Tracking of Mobile Users

DEFF Research Database (Denmark)

Pedersen, Nikolaj Bisgaard; Laursen, Troels; Nielsen, Jimmy Jessen

2012-01-01

Indoors, a user's movements are typically confined by walls, corridors, and doorways, and further he is typically repeating the same movements such as walking between certain points in the building. Conventional indoor localization systems do usually not take these properties of the user's moveme......Indoors, a user's movements are typically confined by walls, corridors, and doorways, and further he is typically repeating the same movements such as walking between certain points in the building. Conventional indoor localization systems do usually not take these properties of the user...... likely trajectory is then calculated using and extended version of the Viterbi algorithm. The results show significant improvements of the proposed algorithm compared to a simpler moving average smoothing....

Method for Improving Indoor Positioning Accuracy Using Extended Kalman Filter

Directory of Open Access Journals (Sweden)

Seoung-Hyeon Lee

2016-01-01

Full Text Available Beacons using bluetooth low-energy (BLE technology have emerged as a new paradigm of indoor positioning service (IPS because of their advantages such as low power consumption, miniaturization, wide signal range, and low cost. However, the beacon performance is poor in terms of the indoor positioning accuracy because of noise, motion, and fading, all of which are characteristics of a bluetooth signal and depend on the installation location. Therefore, it is necessary to improve the accuracy of beacon-based indoor positioning technology by fusing it with existing indoor positioning technology, which uses Wi-Fi, ZigBee, and so forth. This study proposes a beacon-based indoor positioning method using an extended Kalman filter that recursively processes input data including noise. After defining the movement of a smartphone on a flat two-dimensional surface, it was assumed that the beacon signal is nonlinear. Then, the standard deviation and properties of the beacon signal were analyzed. According to the analysis results, an extended Kalman filter was designed and the accuracy of the smartphone’s indoor position was analyzed through simulations and tests. The proposed technique achieved good indoor positioning accuracy, with errors of 0.26 m and 0.28 m from the average x- and y-coordinates, respectively, based solely on the beacon signal.

The Correlation Between Indoor Air Pollution with the Incident of Toddler’s Pneumonia

Directory of Open Access Journals (Sweden)

Ni Nyoman Dayu Mahalastri

2014-09-01

Full Text Available ABSTRACT Pneumonia is a serious health problem in the world, including in Indonesia. Based on the results of Riskesdas 2007, pneumonia was the second ranking cause of death in the proportion of children aged 1–4 years and is under the diarrhea which ranks first. Environmental factors or conditions of the house, especially the air quality in the house is said to be one of the factors that can trigger pneumonia in infants. This study was conducted to determine the correlation of indoor air quality factors with the incidence of toddler’s pneumonia. Type of this study is observational analytic and use case control design. The population of case group was all toddlers who become visitors Mojo Health Center in January 2014 until March 2014 and was diagnosed with pneumonia. While population of control group was all toddlers who become visitors Mojo Health Center in January 2014 until March 2014 and was diagnosed with diseases other than pneumonia. The number of respondents in this study were 60 respondents. The selection of the sample with simple random sampling method. The variables studied were cigarette smoke exposure in the house, size of ventilation and residential density. The results of the analysis using Epi Info StatCalc indicate that exposure to cigarette smoke in the house (OR = 4.00, size of ventilation (OR = 4.03, and residential density (OR = 4.38 has an correlation with incidence of toddler’s pneumonia. It is expected that the public can avoid air pollution in the house in order to prevent toddlers from pneumonia. Keywords: cigarette smoke, size of ventilation, residential density, air quality,                 toddler’s Pneumonia

Indoor air quality

International Nuclear Information System (INIS)

Anon.

1993-01-01

Indoor Air Quality is rapidly becoming a major environmental concern because a significant amount of people spend a substantial amount of time in a variety of different indoor environments. Health effects from indoor pollutants fall into two categories: those that are experienced immediately after exposure and those that do not show up until years later. They are: radon, formaldehyde, asbestos, lead and household organic chemicals. The authors presented a source-by-source look at the most common indoor air pollutants, their potential health effects, and ways to reduce their levels in the home. There are three basic strategies to improve indoor air quality: one method is source control, another is through ventilation improvements, and the third is the utilization of some sort of mechanical device such as air cleaners

Technical Update: Johnson Space Center system using a solid electrolytic cell in a remote location to measure oxygen fugacities in CO/CO2 controlled-atmosphere furnaces

Science.gov (United States)

Jurewicz, A. J. G.; Williams, R. J.; Le, L.; Wagstaff, J.; Lofgren, G.; Lanier, A.; Carter, W.; Roshko, A.

1993-01-01

Details are given for the design and application of a (one atmosphere) redox-control system. This system differs from that given in NASA Technical Memorandum 58234 in that it uses a single solid-electrolytic cell in a remote location to measure the oxygen fugacities of multiple CO/CO2 controlled-atmosphere furnaces. This remote measurement extends the range of sample-furnace conditions that can be measured using a solid-electrolytic cell, and cuts costs by extending the life of the sensors and by minimizing the number of sensors in use. The system consists of a reference furnace and an exhaust-gas manifold. The reference furnace is designed according to the redox control system of NASA Technical Memorandum 58234, and any number of CO/CO2 controlled-atmosphere furnaces can be attached to the exhaust-gas manifold. Using the manifold, the exhaust gas from individual CO/CO2 controlled atmosphere furnaces can be diverted through the reference furnace, where a solid-electrolyte cell is used to read the ambient oxygen fugacity. The oxygen fugacity measured in the reference furnace can then be used to calculate the oxygen fugacity in the individual CO/CO2 controlled-atmosphere furnace. A BASIC computer program was developed to expedite this calculation.

Radiant floor cooling coupled with dehumidification systems in residential buildings: A simulation-based analysis

International Nuclear Information System (INIS)

Zarrella, Angelo; De Carli, Michele; Peretti, Clara

2014-01-01

Highlights: • The floor radiant cooling in a typical apartment is analyzed. • Dehumidification devices, fan-coil and mechanical ventilation are compared. • The results are analyzed in terms of both thermal comfort and energy consumption. • The energy consumption of the dehumidifiers is higher than that of other systems. • The mechanical ventilation decreases the moisture level better than other systems. - Abstract: The development of radiant cooling has stimulated an interest in new systems based on coupling ventilation with radiant cooling. However, radiant cooling systems may cause condensation to form on an active surface under warm and humid conditions during the cooling season. This phenomenon occurs when surface temperature falls below dew point. To prevent condensation, air humidity needs to be reduced with a dehumidification device or a mechanical ventilation system. There are two main options to achieve this. The first is to use dehumidification devices that reduce humidity, but are not coupled with ventilation, i.e. devices that handle room air and leave air change to infiltrations. The second is to combine a mechanical ventilation system with dehumidifying finned coils. This study analyzes the floor radiant cooling of a typical residential apartment within a multi-storey building in three Italian climate zones by means of a detailed simulation tool. Five systems were compared in terms of both indoor thermal comfort and energy consumption: radiant cooling without dehumidification; radiant cooling with a soft dehumidification device; radiant cooling with a dehumidification device which also supplies sensible cooling; radiant cooling coupled with fan coils; and radiant cooling with a mechanical ventilation system which dehumidifies and cools

Methodology developed to make the Quebec indoor radon potential map

Energy Technology Data Exchange (ETDEWEB)

Drolet, Jean-Philippe, E-mail: jean-philippe.drolet@ete.inrs.ca [Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec (Canada); Martel, Richard [Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec (Canada); Poulin, Patrick [Institut national de santé publique du Québec (INSPQ), 945 avenue Wolfe, G1V 5B3 Quebec (Canada); Dessau, Jean-Claude [Agence de la santé et des services sociaux des Laurentides, 1000 rue Labelle, J7Z 5 N6 Saint-Jérome (Canada)

2014-03-01

This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas. It was shown that it is possible to determine thresholds for the three criteria that implied statistically significant different levels of radon potential using Kruskal–Wallis one way analyses of variance by ranks. The three discretized radiogeochemical datasets were combined into a total predicted radon potential that sampled 98% of the studied area. The combination process was also based on Kruskal–Wallis one way ANOVA. Four statistically significant different predicted radon potential levels were created: low, medium, high and very high. Respectively 10 and 13% of the dwellings exceed the Canadian radon guideline of 200 Bq/m{sup 3} in low and medium predicted radon potentials. These proportions rise up to 22 and 45% respectively for high and very high predicted radon potentials. This predictive map of indoor radon potential based on the radiogeochemical data was validated using a map of confirmed radon exposure in homes based on the basement radon measurements. It was shown that the map of predicted radon potential based on the radiogeochemical data was reliable to identify radon-prone areas even in zones where no indoor radon measurement exists. - Highlights: • 5 radiogeochemical datasets were used to map the geogenic indoor radon potential. • An indoor radon potential was determined for

The effects of vegetation on indoor thermal comfort

DEFF Research Database (Denmark)

Pastore, Luisa; Corrao, Rossella; Heiselberg, Per Kvols

2017-01-01

Highlights •A multi-scale simulation methodology to assess the effects of vegetation on thermal comfort is used. •It application is shown on a case of urban and building retrofit intervention. •The effect of plants on the microclimate and indoor environment is assessed. •A decrease of up to 4.8 °C...... in indoor temperature is registered. •The final impact on the indoor thermal comfort based on the adaptive model is determined....

Novel silicone-based polymer containing active methylene designed for the removal of indoor formaldehyde

Energy Technology Data Exchange (ETDEWEB)

Niu, Song, E-mail: niusong84@163.com; Yan, Hongxia, E-mail: hongxiayan@nwpu.edu.cn

2015-04-28

Highlights: • A novel silicone-based polymer with active methylene was explored. • Surface tension of liquid paints could be lowered using the polymer. • The polymer was easy to migrate toward the air-coating interface. • Free HCHO could effectively be removed using the polymer. • A lights on HCHO reduction without complicated preparation procedure was shielded. - Abstract: Indoor air pollution is caused inevitably due to complicated home decoration, in which formaldehyde is one of the most typical pollutants. It will be a convenient, economical and effective strategy to remove indoor formaldehyde if imparting a feature of formaldehyde removal to decorative coatings. We have successfully explored a novel silicone-based polymer containing active methylene used as a formaldehyde absorbent in coatings via a straightforward transesterification process using inexpensive and easily available chemicals. The polymer has been characterized by {sup 13}C NMR, FTIR, GC and GPC. Formaldehyde removal capacity of the coating films containing different contents of the polymer has been investigated. The results indicated that coatings incorporating 4 wt% of the polymer could make the coating films exhibit significant improvement on formaldehyde removal including purificatory performance (>85%) and durability of purificatory effect (>60%), compared to those consisting of absorbents without any silicon, and improve yellowing resistance performance, while other properties, such as gloss, adhesion, pencil hardness, flexibility and impact resistance, were kept almost unaffected. The chemical absorption process of the silicone-based polymer filled in interior decorative coatings is demonstrated as a promising technology to purify indoor formaldehyde and thus can reduce the harm to individuals.

Experimental Analysis of Cool Traditional Solar Shading Systems for Residential Buildings

Directory of Open Access Journals (Sweden)

Anna Laura Pisello

2015-03-01

Full Text Available In recent years there has been a growing interest in the development and thermal-energy analysis of passive solutions for reducing building cooling needs and thus improving indoor thermal comfort conditions. In this view, several studies were carried out about cool roofs and cool coatings, producing acknowledged mitigation effects on urban heat island phenomenon. The purpose of this work is to investigate the thermal-energy performance of cool louvers of shutters, usually installed in residential buildings, compared to dark color traditional shading systems. To this aim, two full-scale prototype buildings were continuously monitored under summer conditions and the role of the cool shutter in reducing the overheating of the shading system and the energy requirements for cooling was analyzed. After an in-lab optical analysis of the cool coating, showing a huge solar reflectance increase with respect to the traditional configuration, i.e., by about 75%, field monitoring results showed that the cool shutter is able to decrease the indoor air temperature up to 2 °C under free floating conditions. The corresponding energy saving was about 25%, with even much higher peaks during very hot summer conditions.

Dealing with Insufficient Location Fingerprints in Wi-Fi Based Indoor Location Fingerprinting

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Kai Dong

2017-01-01

Full Text Available The development of the Internet of Things has accelerated research in the indoor location fingerprinting technique, which provides value-added localization services for existing WLAN infrastructures without the need for any specialized hardware. The deployment of a fingerprinting based localization system requires an extremely large amount of measurements on received signal strength information to generate a location fingerprint database. Nonetheless, this requirement can rarely be satisfied in most indoor environments. In this paper, we target one but common situation when the collected measurements on received signal strength information are insufficient, and show limitations of existing location fingerprinting methods in dealing with inadequate location fingerprints. We also introduce a novel method to reduce noise in measuring the received signal strength based on the maximum likelihood estimation, and compute locations from inadequate location fingerprints by using the stochastic gradient descent algorithm. Our experiment results show that our proposed method can achieve better localization performance even when only a small quantity of RSS measurements is available. Especially when the number of observations at each location is small, our proposed method has evident superiority in localization accuracy.

Indoor air quality in hairdressing salons in Taipei.

Science.gov (United States)

Chang, C-J; Cheng, S-F; Chang, P-T; Tsai, S-W

2018-01-01

To improve indoor air quality and to protect public health, Taiwan has enacted the "Indoor Air Quality Act (IAQ Act)" in 2012. For the general public, the indoor air quality in hair salons is important because it is a popular location that people will often visit for hair treatments. However, only a few exposure assessments regarding air pollutants have previously been performed in hair salons. To assess the air quality of hairdressing environments in Taipei, ten hairdressing salons were included for a walk-through survey in this study. In addition, the airborne concentrations of formaldehyde, volatile organic compounds (VOCs), CO 2 , and phthalate esters were also determined in 5 salons. Charcoal, XAD-2, and OVS-Tenax tubes were used for the air sampling, while the samples were analyzed with gas chromatography/mass spectrometer. It was found that the products used in hair salons contained various chemicals. In fact, from the walk-through survey, a total of 387 different ingredients were found on 129 hair product labels. The hair salons were not well ventilated, with CO 2 levels of 600 to 3576 ppm. The formaldehyde concentrations determined in this study ranged from 12.40 to 1.04 × 10 3  μg m -3 , and the maximum level was above the permissible exposure limit (PEL) of US Occupational Safety and Health Administration (US OSHA). Additionally, 83% of the samples were with levels higher than the standard regulated by Taiwan's IAQ Act. The concentrations of VOCs and phthalate esters were below the occupational exposure limits (OELs), but higher than what was found in general residential environments. The hair products were considered as the major source of air pollutants because significantly higher concentrations were found around the working areas. The number of perming treatments, the number of workers, and the frequency of using formaldehyde releasing products, were found to be associated with the levels of formaldehyde. This study indicates that efforts are

A semi-interactive panorama based 3D reconstruction framework for indoor scenes

NARCIS (Netherlands)

Dang, T.K.; Worring, M.; Bui, T.D.

2011-01-01

We present a semi-interactive method for 3D reconstruction specialized for indoor scenes which combines computer vision techniques with efficient interaction. We use panoramas, popularly used for visualization of indoor scenes, but clearly not able to show depth, for their great field of view, as

Integrated algorithms for RFID-based multi-sensor indoor/outdoor positioning solutions

Science.gov (United States)

Zhu, Mi.; Retscher, G.; Zhang, K.

2011-12-01

Position information is very important as people need it almost everywhere all the time. However, it is a challenging task to provide precise positions indoor/outdoor seamlessly. Outdoor positioning has been widely studied and accurate positions can usually be achieved by well developed GPS techniques but these techniques are difficult to be used indoors since GPS signal reception is limited. The alternative techniques that can be used for indoor positioning include, to name a few, Wireless Local Area Network (WLAN), bluetooth and Ultra Wideband (UWB) etc.. However, all of these have limitations. The main objectives of this paper are to investigate and develop algorithms for a low-cost and portable indoor personal positioning system using Radio Frequency Identification (RFID) and its integration with other positioning systems. An RFID system consists of three components, namely a control unit, an interrogator and a transponder that transmits data and communicates with the reader. An RFID tag can be incorporated into a product, animal or person for the purpose of identification and tracking using radio waves. In general, for RFID positioning in urban and indoor environments three different methods can be used, including cellular positioning, trilateration and location fingerprinting. In addition, the integration of RFID with other technologies is also discussed in this paper. A typical combination is to integrate RFID with relative positioning technologies such as MEMS INS to bridge the gaps between RFID tags for continuous positioning applications. Experiments are shown to demonstrate the improvements of integrating multiple sensors with RFID which can be employed successfully for personal positioning.

Finding dense locations in indoor tracking data

DEFF Research Database (Denmark)

Ahmed, Tanvir; Pedersen, Torben Bach; Lu, Hua

2014-01-01

for semi-constrained indoor movement, and then uses this to map raw tracking records into mapping records representing object entry and exit times in particular locations. Then, an efficient indexing structure, the Dense Location Time Index (DLT-Index) is proposed for indexing the time intervals...... of the mapping table, along with associated construction, query processing, and pruning techniques. The DLT-Index supports very efficient aggregate point queries, interval queries, and dense location queries. A comprehensive experimental study with real data shows that the proposed techniques can efficiently......Finding the dense locations in large indoor spaces is very useful for getting overloaded locations, security, crowd management, indoor navigation, and guidance. Indoor tracking data can be very large and are not readily available for finding dense locations. This paper presents a graph-based model...

Indoor Semantic Modelling for Routing: The Two-Level Routing Approach for Indoor Navigation

Directory of Open Access Journals (Sweden)

Liu Liu

2017-11-01

stand for their connectivity; the detailed (second level focuses on transition spaces such as openings and Spaces of Interest (SOI, and geometric networks are generated regarding these spaces. Nodes of a geometric network refers to locations of doors, windows and subspaces (SOIs inside of the larger spaces; and the edges represent detailed paths among these geometric nodes. A combination of the two levels can represent complex buildings in specified spaces, which avoids maintaining a largescale complete network. User preferences on ordered SOIs are considered in routing on the logical network, and preferences on ordered Points of Interest (POI are adopted in routing on geometric networks. In a geometric network, accessible obstacle-avoiding paths can be computed for users with different sizes. To facilitate automatic generation of the two types of network in any building, a new data model named Indoor Navigation Space Model (INSM is proposed to store connectivity, semantics and geometry of indoor spaces for buildings. Abundant semantics of building components are designed in INSM based on navigational functionalities, such as VerticalUnit(VU and HorizontalConnector(HC as vertical and horizontal passages for pedestrians. The INSM supports different subdivision ways of a building in which indoor spaces can be assigned proper semantics. A logical and geometric network can be automatically derived from INSM, and they can be used individually or together for indoor routing. Thus, different routing options are designed. Paths can be provided by using either the logical network when some users are satisfied with a rough description of the path (e.g., the name of spaces, or a geometric path is automatically computed for a user who needs only a detailed path which shows how obstacles can be avoided. The two-level routing approach integrates both logical and geometric networks to obtain paths, when a user provides her/his preferences on SOIs and POIs. For example, routing results

A Case Study of Indoor Garden-Based Learning with Hydroponics and Aquaponics: Evaluating Pro-Environmental Knowledge, Perception, and Behavior Change

Science.gov (United States)

Jon Schneller, Andrew; Schofield, Casey A.; Frank, Jenna; Hollister, Eliza; Mamuszka, Lauren

2015-01-01

This article reports on a mixed methods evaluation of an indoor garden-based learning curriculum for 5th and 6th graders which incorporated aquaponics and hydroponics technologies. This study provides a better understanding of the extent to which indoor gardening technologies can be used within the formal curriculum as an effective teaching tool.…

Coping with Indoor Air Pollution

Science.gov (United States)

... Pollution > Coping with Indoor Air Pollution Font: Outdoor Pollution Indoor Air Pollution Asthma Triggers For Kids and Teachers Coping with Indoor Air Pollution Indoor air pollution is irritating to everyone: But people who ...

INDOOR POSITIONING AND NAVIGATION BASED ON CONTROL SPHERECAL PANORAMIC IMAGES

Directory of Open Access Journals (Sweden)

T.-C. Huang

2016-06-01

Full Text Available Continuous indoor and outdoor positioning and navigation is the goal to achieve in the field of mobile mapping technology. However, accuracy of positioning and navigation will be largely degraded in indoor or occluded areas, due to receiving weak or less GNSS signals. Targeting the need of high accuracy indoor and outdoor positioning and navigation for mobile mapping applications, the objective of this study is to develop a novel method of indoor positioning and navigation with the use of spherical panoramic image (SPI. Two steps are planned in the technology roadmap. First, establishing a control SPI database that contains a good number of well-distributed control SPIs pre-acquired in the target space. A control SPI means an SPI with known exterior orientation parameters, which can be solved with a network bundle adjustment of SPIs. Having a control SPI database, the target space will be ready to provide the service of positioning and navigation. Secondly, the position and orientation of a newly taken SPI can be solved by using overlapped SPIs searched from the control SPI database. The method of matching SPIs and finding conjugate image features will be developed and tested. Two experiments will be planned and conducted in this paper to test the feasibility and validate the test results of the proposed methods. Analysis of appropriate number and distribution of needed control SPIs will also be included in the experiments with respect to different test cases.

Respiratory Diseases in University Students Associated with Exposure to Residential Dampness or Mold

Directory of Open Access Journals (Sweden)

Mathieu Lanthier-Veilleux

2016-11-01

Full Text Available University students are frequently exposed to residential dampness or mold (i.e., visible mold, mold odor, dampness, or water leaks, a well-known contributor to asthma, allergic rhinitis, and respiratory infections. This study aims to: (a describe the prevalence of these respiratory diseases among university students; and (b examine the independent contribution of residential dampness or mold to these diseases. An online survey was conducted in March 2014 among the 26,676 students registered at the Université de Sherbrooke (Quebec, Canada. Validated questions and scores were used to assess self-reported respiratory diseases (i.e., asthma-like symptoms, allergic rhinitis, and respiratory infections, residential dampness or mold, and covariates (e.g., student characteristics. Using logistic regressions, the crude and adjusted odd ratios between residential dampness or mold and self-reported respiratory diseases were examined. Results from the participating students (n = 2097; response rate: 8.1% showed high prevalence of allergic rhinitis (32.6%; 95% CI: 30.6–34.7, asthma-like symptoms (24.0%; 95% CI: 22.1–25.8 and respiratory infections (19.4%; 95% CI: 17.7–21.2. After adjustment, exposure to residential dampness or mold was associated with allergic rhinitis (OR: 1.25; 95% CI: 1.01–1.55 and asthma-like symptoms (OR: 1.70; 95% CI: 1.37–2.11, but not with respiratory infections (OR: 1.07; 95% CI: 0.85–1.36. Among symptomatic students, this exposure was also associated with uncontrolled and burdensome respiratory symptoms (p < 0.01. University students report a high prevalence of allergic rhinitis, asthma-like symptoms and respiratory infections. A common indoor hazard, residential dampness or mold, may play a role in increasing atopic respiratory diseases and their suboptimal control in young adults. These results emphasize the importance for public health organizations to tackle poor housing conditions, especially amongst university

Evaporative Cooler Use Influences Temporal Indoor Relative Humidity but Not Dust Mite Allergen Levels in Homes in a Semi-Arid Climate.

Science.gov (United States)

Johnston, James D; Tuttle, Steven C; Nelson, Morgan C; Bradshaw, Rebecca K; Hoybjerg, Taylor G; Johnson, Julene B; Kruman, Bryce A; Orton, Taylor S; Cook, Ryan B; Eggett, Dennis L; Weber, K Scott

2016-01-01

Concerns about energy consumption and climate change make residential evaporative coolers a popular alternative to central air conditioning in arid and semi-arid climates. However, evaporative coolers have been shown to significantly increase indoor relative humidity and dust mite allergen levels in some studies, while showing no association in other studies. Improved measurement of temporal fluctuations in indoor relative humidity may help identify factors that promote mite growth in homes in dry climates. Dust samples and continuous indoor relative humidity measurements were collected from homes with central air conditioning and homes with evaporative coolers in Utah. Samples were collected over two seasons, winter/spring (Jan-Apr) and summer (July-Sept), 2014. Dust samples were analyzed for Der p 1 and Der f 1 using a two-site monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) analysis. Housing characteristics including age of home, occupant density, and age of mattresses, furniture, and carpeting were also measured. Positive Der p 1 or Der f 1 samples were found in 25.0% of the homes and there was no difference in mean allergen levels by type of air conditioning. Indoor relative humidity was significantly higher in homes with evaporative coolers compared to those with central air conditioning during the summer. Homes with evaporative coolers also spent significantly more time during summer above 55.0% and 65.0% relative humidity compared to central air homes, but not above 75.0%. Findings from this study suggest that increased humidity from evaporative coolers may not be sufficient to exceed the critical equilibrium humidity or maintain humidity excursions for sufficient duration in relatively larger single-family homes in semi-arid climates to support mite growth and reproduction.

Indoor Tanning

Science.gov (United States)

... proof that indoor tanning is safer than tanning outdoors. Indoor tanning systems give concentrated UV exposure regardless ... For example, it’s essential for promoting good bone health. While UV ... a tan to get that benefit. According to the Surgeon General, fair and light- ...

An assessment of ecological and case-control methods for estimating lung cancer risk due to indoor radon

International Nuclear Information System (INIS)

Stidley, C.A.; Samet, J.M.

1992-01-01

Studies of underground miners indicate that indoor radon is an important cause of lung cancer. This finding has raised concern that exposure to radon also causes lung cancer in the general population. Epidemiological studies, including both case-control and ecological approaches, have directly addressed the risks of indoor residential radon; many more case-control studies are in progress. Ecological studies that associate lung-cancer rates with typical indoor radon levels in various geographic areas have not consistently shown positive associations. The results of purportedly negative ecological studies have been used as a basis for questioning the hazards of indoor radon exposure. Because of potentially serious methodologic flaws for testing hypotheses, we examined the ecological method as a tool for assessing lung-cancer risk from indoor radon exposure. We developed a simulation approach that utilizes the Environmental Protection Agency (EPA) radon survey data to assign exposures to individuals within counties. Using the computer-generated data, we compared risk estimates obtained by ecological regression methods with those obtained from other regression methods and with the open-quotes trueclose quotes risks used to generate the data. For many of these simulations, the ecological models, while fitting the summary data well, gave risk estimates that differed considerably from the true risks. For some models, the risk estimates were negatively correlated with exposure, although the assumed relationship was positive. Attempts to improve the ecological models by adding smoking variables, including interaction terms, did not always improve the estimates of risk, which are easily affected by model misspecification. Because exposure situations used in the simulations are realistic, our results show that ecological methods may not accurately estimate the lung-cancer risk associated with indoor radon exposure

Waste-based materials; capability, application and impact on indoor environment – literature review

DEFF Research Database (Denmark)

Krejcirikova, Barbora; Rode, Carsten; Kolarik, Jakub

2014-01-01

This paper reviews and discusses various sustainable materials utilizing waste products with the focus on their properties having an impact on the indoor environmental conditions and indoor air quality (IAQ). Materials included in the review are selected considering the following aspects......: sustainability, cradle to cradle perspective, application, their impact on indoor environment and human well-being. The attempt of the paper is to cover a wide spectrum of information so to provide better understanding of waste utilization in construction industry....

Frequency Based Real-time Pricing for Residential Prosumers

Science.gov (United States)

Hambridge, Sarah Mabel

This work is the first to explore frequency based pricing for secondary frequency control as a price-reactive control mechanism for residential prosumers. A frequency based real-time electricity rate is designed as an autonomous market control mechanism for residential prosumers to provide frequency support as an ancillary service. In addition, prosumers are empowered to participate in dynamic energy transactions, therefore integrating Distributed Energy Resources (DERs), and increasing distributed energy storage onto the distributed grid. As the grid transitions towards DERs, a new market based control system will take the place of the legacy distributed system and possibly the legacy bulk power system. DERs provide many benefits such as energy independence, clean generation, efficiency, and reliability to prosumers during blackouts. However, the variable nature of renewable energy and current lack of installed energy storage on the grid will create imbalances in supply and demand as uptake increases, affecting the grid frequency and system operation. Through a frequency-based electricity rate, prosumers will be encouraged to purchase energy storage systems (ESS) to offset their neighbor's distributed generation (DG) such as solar. Chapter 1 explains the deregulation of the power system and move towards Distributed System Operators (DSOs), as prosumers become owners of microgrids and energy cells connected to the distributed system. Dynamic pricing has been proposed as a benefit to prosumers, giving them the ability to make decisions in the energy market, while also providing a way to influence and control their behavior. Frequency based real-time pricing is a type of dynamic pricing which falls between price-reactive control and transactive control. Prosumer-to-prosumer transactions may take the place of prosumer-to-utility transactions, building The Energy Internet. Frequency based pricing could be a mechanism for determining prosumer prices and supporting

Service Differentiation in Residential Broadband Networks

DEFF Research Database (Denmark)

Sigurdsson, Halldór Matthias

2004-01-01

As broadband gains widespread adoption with residential users, revenue generating voice- and video-services have not yet taken off. This slow uptake is often attributed to lack of Quality of Service management in residential broadband networks. To resolve this and induce service variety, network...... access providers are implementing service differentiation in their networks where voice and video gets prioritised before data. This paper discusses the role of network access providers in multipurpose packet based networks and the available migration strategies for supporting multimedia services...... in digital subscriber line (DSL) based residential broadband networks. Four possible implementation scenarios and their technical characteristics and effects are described. To conclude, the paper discusses how network access providers can be induced to open their networks for third party service providers....

Indoor Air Quality

DEFF Research Database (Denmark)

Selman, Ayser Dawod; Heiselberg, Per

Overall purpose of the research is to provide an overview of the relevance and importance of various defined Indoor Air Quality (IAQ) parameters in a European perspective. Based on the report it should be possible to prioritize which countries to target for further activities as well as it should...

Physico-Chemical Characterization of Indoor/Outdoor Particulate Matter in Two Residential Houses in Oslo, Norway: Measurements Overview and Physical Properties – URBAN-AEROSOL Project

Czech Academy of Sciences Publication Activity Database

Lazaridis, M.; Aleksandropoulou, V.; Smolík, Jiří; Hansen, J.E.; Glytsos, T.; Kalogerakis, N.; Dahlin, E.

2006-01-01

Roč. 16, č. 4 (2006), s. 282-295 ISSN 0905-6947 Grant - others:ENVK4(XE) CT/2000/00018 Institutional research plan: CEZ:AV0Z40720504 Keywords : indoor air quality * ventilation rate * indoor sources Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.057, year: 2006

Indoor Thermal Factors and Symptoms in Office Workers: Findings from the U.S. EPA BASE Study

Energy Technology Data Exchange (ETDEWEB)

Mendell, Mark; Mirer, Anna

2008-06-01

Some prior research in office buildings has associated higher indoor temperatures even within the recommended thermal comfort range with increased worker symptoms. We reexamined this relationship in data from 95 office buildings in the U.S. Environmental Protection Agency's Building Assessment Survey and Evaluation (BASE) Study. We investigated relationships between building-related symptoms and thermal metrics constructed from real-time measurements. We estimated odds ratios (ORs) and 95percent confidence intervals in adjusted logistic regression models with general estimating equations, overall and by season. Winter indoor temperatures spanned the recommended winter comfort range; summer temperatures were mostly colder than the recommended summer range. Increasing indoor temperatures, overall, were associated with increases in few symptoms. Higher winter indoor temperatures, however, were associated with increases in all symptoms analyzed. Higher summer temperatures, above 23oC, were associated with decreases in most symptoms. Humidity ratio, a metric of absolute humidity, showed few clear associations. Thus, increased symptoms with higher temperatures within the thermal comfort range were found only in winter. In summer, buildings were overcooled, and only the higher observed temperatures were within the comfort range; these were associated with decreased symptoms. Confirmation of these findings would suggest that thermal management guidelines consider health effects as well as comfort.

Comparing clinical and demographic characteristics of people with mental illness in hospital- and community-based residential rehabilitation units in Queensland.

Science.gov (United States)

Meehan, Tom; Stedman, Terry; Parker, Stephen; Curtis, Bretine; Jones, Donna

2017-05-01

Objective The aim of the present study was to examine care pathways and characteristics of mental health consumers participating in both hospital- and community-based residential rehabilitation programs. Methods An audit of consumers (n=240) in all publicly funded residential rehabilitation units in Queensland was performed on the same day in 2013. Data collection focused on demographic characteristics, clinical information and measures of consumer functioning. Results Significant differences emerged for consumers in community- and hospital-based services with regard to age, length of stay, functioning, Mental Health Act status, guardianship status, family contact and risk of violence. Consumers in hospital-based programs have more severe and complex problems. Conclusions Consumers in residential rehabilitation units have high levels of disability, poor physical health and high levels of vulnerability. Nonetheless, it is likely that a sizeable proportion of consumers occupying rehabilitation beds in Queensland could be discharged if more 'step-down' options to move patients on were available. What is known about the topic? A small subgroup of people with severe and complex mental health problems is likely to require time in a residential rehabilitation program. This group is characterised by failure to respond to treatment, severe negative symptoms and some degree of cognitive impairment. What does this paper add? Patients currently occupying residential rehabilitation beds in Queensland have high levels of disability, poor physical health and high levels of vulnerability. Patients in hospital-based programs are more severely disabled than those in community-based programs. What are the implications for practitioners? It is likely that a sizeable proportion of patients occupying rehabilitation beds in Queensland could be discharged if more 'step-down' options were available. Future planning initiatives need to focus on developing a greater array of community

Clustering-based analysis for residential district heating data

DEFF Research Database (Denmark)

Gianniou, Panagiota; Liu, Xiufeng; Heller, Alfred

2018-01-01

The wide use of smart meters enables collection of a large amount of fine-granular time series, which can be used to improve the understanding of consumption behavior and used for consumption optimization. This paper presents a clustering-based knowledge discovery in databases method to analyze r....... These findings will be valuable for district heating utilities and energy planners to optimize their operations, design demand-side management strategies, and develop targeting energy-efficiency programs or policies.......The wide use of smart meters enables collection of a large amount of fine-granular time series, which can be used to improve the understanding of consumption behavior and used for consumption optimization. This paper presents a clustering-based knowledge discovery in databases method to analyze...... residential heating consumption data and evaluate information included in national building databases. The proposed method uses the K-means algorithm to segment consumption groups based on consumption intensity and representative patterns and ranks the groups according to daily consumption. This paper also...

77 FR 28519 - Test Procedure Guidance for Room Air Conditioners, Residential Dishwashers, and Residential...

Science.gov (United States)

2012-05-15

... Guidance for Room Air Conditioners, Residential Dishwashers, and Residential Clothes Washers: Public... procedures for room air conditioners, residential dishwashers, and residential clothes washers. DATES: DOE...'s existing test procedures for residential room air conditioners, residential dishwashers, and...

Suggestions on Strengthening Greening Construction of Ecological Residential Areas

OpenAIRE

Li, Peng

2013-01-01

Greening construction is an important part of the construction of ecological residential areas, but there exist some misunderstandings in greening construction of ecological residential districts at present. Based on the description of functions of green space in ecological residential areas, the summarization of principles of greening design, and the discussion of questions in greening construction of ecological residential districts, some suggestions as well as specific measures for strengt...

Steering Angle Function Algorithm of Morphing of Residential Area

Directory of Open Access Journals (Sweden)

XIE Tian

2015-07-01

Full Text Available A residential area feature morphing method based on steering angle function is presented. To residential area with the same representation under two different scales,transforming the representation of the residential area polygon from vector coordinates to steering angle function,then using the steering angle function to match,and finding out the similarity and the differences between the residential areas under different scale to get the steering angle function of the the residential areas under any middle scale,the final,transforming the middle scale steering angle function to vector coordinates form,and get the middle shape interpolation of the the residential area polygon.Experimental results show:the residential area morphing method by using steering angle function presented can realize the continuous multi-scale representation under the premise of keeping in shape for the residential area with the rectangular boundary features.

Modeling the Temperature Effect of Orientations in Residential Buildings

Directory of Open Access Journals (Sweden)

Sabahat Arif

2012-07-01

Full Text Available Indoor thermal comfort in a building has been an important issue for the environmental sustainability. It is an accepted fact that their designs and planning consume a lot of energy in the modern architecture of 20th and 21st centuries. An appropriate orientation of a building can provide thermally comfortable indoor temperatures which otherwise can consume extra energy to condition these spaces through all the seasons. This experimental study investigates the potential effect of this solar passive design strategy on indoor temperatures and a simple model is presented for predicting indoor temperatures based upon the ambient temperatures.

INDOOR AIR QUALITY AND INHALATION EXPOSURE - SIMULATION TOOL KIT

Science.gov (United States)

A Microsoft Windows-based indoor air quality (IAQ) simulation software package is presented. Named Simulation Tool Kit for Indoor Air Quality and Inhalation Exposure, or IAQX for short, this package complements and supplements existing IAQ simulation programs and is desi...

Residential Consumption Scheduling Based on Dynamic User Profiling

Science.gov (United States)

Mangiatordi, Federica; Pallotti, Emiliano; Del Vecchio, Paolo; Capodiferro, Licia

Deployment of household appliances and of electric vehicles raises the electricity demand in the residential areas and the impact of the building's electrical power. The variations of electricity consumption across the day, may affect both the design of the electrical generation facilities and the electricity bill, mainly when a dynamic pricing is applied. This paper focuses on an energy management system able to control the day-ahead electricity demand in a residential area, taking into account both the variability of the energy production costs and the profiling of the users. The user's behavior is dynamically profiled on the basis of the tasks performed during the previous days and of the tasks foreseen for the current day. Depending on the size and on the flexibility in time of the user tasks, home inhabitants are grouped in, one over N, energy profiles, using a k-means algorithm. For a fixed energy generation cost, each energy profile is associated to a different hourly energy cost. The goal is to identify any bad user profile and to make it pay a highest bill. A bad profile example is when a user applies a lot of consumption tasks and low flexibility in task reallocation time. The proposed energy management system automatically schedules the tasks, solving a multi-objective optimization problem based on an MPSO strategy. The goals, when identifying bad users profiles, are to reduce the peak to average ratio in energy demand, and to minimize the energy costs, promoting virtuous behaviors.

Accurate Simulation of 802.11 Indoor Links: A "Bursty" Channel Model Based on Real Measurements

Directory of Open Access Journals (Sweden)

Agüero Ramón

2010-01-01

Full Text Available We propose a novel channel model to be used for simulating indoor wireless propagation environments. An extensive measurement campaign was carried out to assess the performance of different transport protocols over 802.11 links. This enabled us to better adjust our approach, which is based on an autoregressive filter. One of the main advantages of this proposal lies in its ability to reflect the "bursty" behavior which characterizes indoor wireless scenarios, having a great impact on the behavior of upper layer protocols. We compare this channel model, integrated within the Network Simulator (ns-2 platform, with other traditional approaches, showing that it is able to better reflect the real behavior which was empirically assessed.

Search of medical literature for indoor carbon monoxide exposure

Energy Technology Data Exchange (ETDEWEB)

Brennan, T.; Ivanovich, M.

1995-12-01

This report documents a literature search on carbon monoxide. The search was limited to the medical and toxicological databases at the National Library of Medicine (MEDLARS). The databases searched were Medline, Toxline and TOXNET. Searches were performed using a variety of strategies. Combinations of the following keywords were used: carbon, monoxide, accidental, residential, occult, diagnosis, misdiagnosis, heating, furnace, and indoor. The literature was searched from 1966 to the present. Over 1000 references were identified and summarized using the following abbreviations: The major findings of the search are: (1) Acute and subacute carbon monoxide exposures result in a large number of symptoms affecting the brain, kidneys, respiratory system, retina, and motor functions. (2) Acute and subacute carbon monoxide (CO) poisonings have been misdiagnosed on many occasions. (3) Very few systematic investigations have been made into the frequency and consequences of carbon monoxide poisonings.

Providing Databases for Different Indoor Positioning Technologies: Pros and Cons of Magnetic Field and Wi-Fi Based Positioning

Directory of Open Access Journals (Sweden)

Joaquín Torres-Sospedra

2016-01-01

Full Text Available Localization is one of the main pillars for indoor services. However, it is still very difficult for the mobile sensing community to compare state-of-the-art indoor positioning systems due to the scarcity of publicly available databases. To make fair and meaningful comparisons between indoor positioning systems, they must be evaluated in the same situation, or in the same sets of situations. In this paper, two databases are introduced for studying the performance of magnetic field and Wi-Fi fingerprinting based positioning systems in the same environment (i.e., indoor area. The “magnetic” database contains more than 40,000 discrete captures (270 continuous samples, whereas the “Wi-Fi” one contains 1,140 ones. The environment and both databases are fully detailed in this paper. A set of experiments is also presented where two simple but effective baselines have been developed to test the suitability of the databases. Finally, the pros and cons of both types of positioning techniques are discussed in detail.

Peripheral and gastrointestinal immune systems of healthy cattle raised outdoors at pasture or indoors on a concentrate-based ration

Directory of Open Access Journals (Sweden)

Reilly Petrina

2010-03-01

Full Text Available Abstract Background Despite an increasing preference of consumers for beef produced from more extensive pasture-based production systems and potential human health benefits from the consumption of such beef, data regarding the health status of animals raised on pasture are limited. The objective of this study was to characterise specific aspects of the bovine peripheral and the gastrointestinal muscosal immune systems of cattle raised on an outdoor pasture system in comparison to animals raised on a conventional intensive indoor concentrate-based system. Results A number of in vitro functional tests of immune cells suggested subtle differences between the animals on the outdoor versus indoor production systems. There was a decrease in the number of neutrophils and monocytes engaged in phagocytosis in outdoor cattle (P P P P P P P Conclusion Despite distinctly contrasting production systems, only subtle differences were identified in the peripheral immune parameters measured between cattle raised at pasture in comparison to animals raised on a conventional intensive indoor concentrate-based production system.

Indoor air quality inspection and analysis system based on gas sensor array

Science.gov (United States)

Gao, Xiang; Wang, Mingjiang; Fan, Binwen

2017-08-01

A detection and analysis system capable of measuring the concentration of four major gases in indoor air is designed. It uses four gas sensors constitute a gas sensor array, to achieve four indoor gas concentration detection, while the detection of data for further processing to reduce the cross-sensitivity between the gas sensor to improve the accuracy of detection.

Climate change and health: Indoor heat exposure in vulnerable populations

International Nuclear Information System (INIS)

White-Newsome, Jalonne L.; Sánchez, Brisa N.; Jolliet, Olivier; Zhang, Zhenzhen; Parker, Edith A.; Timothy Dvonch, J.; O'Neill, Marie S.

2012-01-01

Introduction: Climate change is increasing the frequency of heat waves and hot weather in many urban environments. Older people are more vulnerable to heat exposure but spend most of their time indoors. Few published studies have addressed indoor heat exposure in residences occupied by an elderly population. The purpose of this study is to explore the relationship between outdoor and indoor temperatures in homes occupied by the elderly and determine other predictors of indoor temperature. Materials and methods: We collected hourly indoor temperature measurements of 30 different homes; outdoor temperature, dewpoint temperature, and solar radiation data during summer 2009 in Detroit, MI. We used mixed linear regression to model indoor temperatures' responsiveness to weather, housing and environmental characteristics, and evaluated our ability to predict indoor heat exposures based on outdoor conditions. Results: Average maximum indoor temperature for all locations was 34.85 °C, 13.8 °C higher than average maximum outdoor temperature. Indoor temperatures of single family homes constructed of vinyl paneling or wood siding were more sensitive than brick homes to outdoor temperature changes and internal heat gains. Outdoor temperature, solar radiation, and dewpoint temperature predicted 38% of the variability of indoor temperatures. Conclusions: Indoor exposures to heat in Detroit exceed the comfort range among elderly occupants, and can be predicted using outdoor temperatures, characteristics of the housing stock and surroundings to improve heat exposure assessment for epidemiological investigations. Weatherizing homes and modifying home surroundings could mitigate indoor heat exposure among the elderly.

Indoor Climate Quality Assessment -

DEFF Research Database (Denmark)

Ansaldi, Roberta; Asadi, Ehsan; Costa, José Joaquim

This Guidebook gives building professionals useful support in the practical measurements and monitoring of the indoor climate in buildings. It is evident that energy consumption in a building is directly influenced by required and maintained indoor comfort level. Wireless technologies for measure...... for measurement and monitoring have allowed a significantly increased number of possible applications, especially in existing buildings. The Guidebook illustrates several cases with the instrumentation of the monitoring and assessment of indoor climate.......This Guidebook gives building professionals useful support in the practical measurements and monitoring of the indoor climate in buildings. It is evident that energy consumption in a building is directly influenced by required and maintained indoor comfort level. Wireless technologies...

Indoor aerosol modeling for assessment of exposure and respiratory tract deposited dose

Science.gov (United States)

Hussein, Tareq; Wierzbicka, Aneta; Löndahl, Jakob; Lazaridis, Mihalis; Hänninen, Otto

2015-04-01

Air pollution is one of the major environmental problems that influence people's health. Exposure to harmful particulate matter (PM) occurs both outdoors and indoors, but while people spend most of their time indoors, the indoor exposures tend to dominate. Moreover, higher PM concentrations due to indoor sources and tightness of indoor environments may substantially add to the outdoor originating exposures. Empirical and real-time assessment of human exposure is often impossible; therefore, indoor aerosol modeling (IAM) can be used as a superior method in exposure and health effects studies. This paper presents a simple approach in combining available aerosol-based modeling techniques to evaluate the real-time exposure and respiratory tract deposited dose based on particle size. Our simple approach consists of outdoor aerosol data base, IAM simulations, time-activity pattern data-base, physical-chemical properties of inhaled aerosols, and semi-empirical deposition fraction of aerosols in the respiratory tract. These modeling techniques allow the characterization of regional deposited dose in any metric: particle mass, particle number, and surface area. The first part of this presentation reviews recent advances in simple mass-balance based modeling methods that are needed in analyzing the health relevance of indoor exposures. The second part illustrates the use of IAM in the calculations of exposure and deposited dose. Contrary to previous methods, the approach presented is a real-time approach and it goes beyond the exposure assessment to provide the required information for the health risk assessment, which is the respiratory tract deposited dose. This simplified approach is foreseen to support epidemiological studies focusing on exposures originating from both indoor and outdoor sources.

An Evaluation of Antifungal Agents for the Treatment of Fungal Contamination in Indoor Air Environments

Directory of Open Access Journals (Sweden)

Senthaamarai Rogawansamy

2015-06-01

inhibit the growth of fungal genera found in the indoor air environment. The results indicate that tea tree oil was the most effective antifungal agent tested, and may have industrial application for the remediation of fungal contamination in residential and occupational buildings.

An evaluation of antifungal agents for the treatment of fungal contamination in indoor air environments.

Science.gov (United States)

Rogawansamy, Senthaamarai; Gaskin, Sharyn; Taylor, Michael; Pisaniello, Dino

2015-06-02

of fungal genera found in the indoor air environment. The results indicate that tea tree oil was the most effective antifungal agent tested, and may have industrial application for the remediation of fungal contamination in residential and occupational buildings.

Defining indoor heat thresholds for health in the UK.

Science.gov (United States)

Anderson, Mindy; Carmichael, Catriona; Murray, Virginia; Dengel, Andy; Swainson, Michael

2013-05-01

It has been recognised that as outdoor ambient temperatures increase past a particular threshold, so do mortality/morbidity rates. However, similar thresholds for indoor temperatures have not yet been identified. Due to a warming climate, the non-sustainability of air conditioning as a solution, and the desire for more energy-efficient airtight homes, thresholds for indoor temperature should be defined as a public health issue. The aim of this paper is to outline the need for indoor heat thresholds and to establish if they can be identified. Our objectives include: describing how indoor temperature is measured; highlighting threshold measurements and indices; describing adaptation to heat; summary of the risk of susceptible groups to heat; reviewing the current evidence on the link between sleep, heat and health; exploring current heat and health warning systems and thresholds; exploring the built environment and the risk of overheating; and identifying the gaps in current knowledge and research. A global literature search of key databases was conducted using a pre-defined set of keywords to retrieve peer-reviewed and grey literature. The paper will apply the findings to the context of the UK. A summary of 96 articles, reports, government documents and textbooks were analysed and a gap analysis was conducted. Evidence on the effects of indoor heat on health implies that buildings are modifiers of the effect of climate on health outcomes. Personal exposure and place-based heat studies showed the most significant correlations between indoor heat and health outcomes. However, the data are sparse and inconclusive in terms of identifying evidence-based definitions for thresholds. Further research needs to be conducted in order to provide an evidence base for threshold determination. Indoor and outdoor heat are related but are different in terms of language and measurement. Future collaboration between the health and building sectors is needed to develop a common

Evolution of the indoor biome.

Science.gov (United States)

Martin, Laura J; Adams, Rachel I; Bateman, Ashley; Bik, Holly M; Hawks, John; Hird, Sarah M; Hughes, David; Kembel, Steven W; Kinney, Kerry; Kolokotronis, Sergios-Orestis; Levy, Gabriel; McClain, Craig; Meadow, James F; Medina, Raul F; Mhuireach, Gwynne; Moreau, Corrie S; Munshi-South, Jason; Nichols, Lauren M; Palmer, Clare; Popova, Laura; Schal, Coby; Täubel, Martin; Trautwein, Michelle; Ugalde, Juan A; Dunn, Robert R

2015-04-01

Few biologists have studied the evolutionary processes at work in indoor environments. Yet indoor environments comprise approximately 0.5% of ice-free land area--an area as large as the subtropical coniferous forest biome. Here we review the emerging subfield of 'indoor biome' studies. After defining the indoor biome and tracing its deep history, we discuss some of its evolutionary dimensions. We restrict our examples to the species found in human houses--a subset of the environments constituting the indoor biome--and offer preliminary hypotheses to advance the study of indoor evolution. Studies of the indoor biome are situated at the intersection of evolutionary ecology, anthropology, architecture, and human ecology and are well suited for citizen science projects, public outreach, and large-scale international collaborations. Copyright © 2015 Elsevier Ltd. All rights reserved.

VOLATILIZATION RATES FROM WATER TO INDOOR AIR ...

Science.gov (United States)

Contaminated water can lead to volatilization of chemicals to residential indoor air. Previous research has focused on only one source (shower stalls) and has been limited to chemicals in which gas-phase resistance to mass transfer is of marginal significance. As a result, attempts to extrapolate chemical emissions from high-volatility chemicals to lower volatility chemicals, or to sources other than showers, have been difficult or impossible. This study involved the development of two-phase, dynamic mass balance models for estimating chemical emissions from washing machines, dishwashers, and bathtubs. An existing model was adopted for showers only. Each model required the use of source- and chemical-specific mass transfer coefficients. Air exchange (ventilation) rates were required for dishwashers and washing machines as well. These parameters were estimated based on a series of 113 experiments involving 5 tracer chemicals (acetone, ethyl acetate, toluene, ethylbenzene, and cyclohexane) and 4 sources (showers, bathtubs, washing machines, and dishwashers). Each set of experiments led to the determination of chemical stripping efficiencies and mass transfer coefficients (overall, liquid-phase, gas-phase), and to an assessment of the importance of gas- phase resistance to mass transfer. Stripping efficiencies ranged from 6.3% to 80% for showers, 2.6% to 69% for bathtubs, 18% to 100% for dishwashers, and 3.8% to 100% for washing machines. Acetone and cyclohexane al

Indoor air quality analysis based on Hadoop

International Nuclear Information System (INIS)

Tuo, Wang; Liang, Yu; Weihong, Cui; Yunhua, Sun; Song, Tian

2014-01-01

The air of the office environment is our research object. The data of temperature, humidity, concentrations of carbon dioxide, carbon monoxide and ammonia are collected peer one to eight seconds by the sensor monitoring system. And all the data are stored in the Hbase database of Hadoop platform. With the help of HBase feature of column-oriented store and versioned (automatically add the time column), the time-series data sets are bulit based on the primary key Row-key and timestamp. The parallel computing programming model MapReduce is used to process millions of data collected by sensors. By analysing the changing trend of parameters' value at different time of the same day and at the same time of various dates, the impact of human factor and other factors on the room microenvironment is achieved according to the liquidity of the office staff. Moreover, the effective way to improve indoor air quality is proposed in the end of this paper

Indoor air quality analysis based on Hadoop

Science.gov (United States)

Tuo, Wang; Yunhua, Sun; Song, Tian; Liang, Yu; Weihong, Cui

2014-03-01

The air of the office environment is our research object. The data of temperature, humidity, concentrations of carbon dioxide, carbon monoxide and ammonia are collected peer one to eight seconds by the sensor monitoring system. And all the data are stored in the Hbase database of Hadoop platform. With the help of HBase feature of column-oriented store and versioned (automatically add the time column), the time-series data sets are bulit based on the primary key Row-key and timestamp. The parallel computing programming model MapReduce is used to process millions of data collected by sensors. By analysing the changing trend of parameters' value at different time of the same day and at the same time of various dates, the impact of human factor and other factors on the room microenvironment is achieved according to the liquidity of the office staff. Moreover, the effective way to improve indoor air quality is proposed in the end of this paper.

Indoor air: Reference bibliography

International Nuclear Information System (INIS)

Campbell, D.; Staves, D.; McDonald, S.

1989-07-01

The U. S. Environmental Protection Agency initially established the indoor air Reference Bibliography in 1987 as an appendix to the Indoor Air Quality Implementation Plan. The document was submitted to Congress as required under Title IV--Radon Gas and Indoor Air Quality Research of the Superfund Amendments and Reauthorization Act of 1986. The Reference Bibliography is an extensive bibliography of reference materials on indoor air pollution. The Bibliography contains over 4500 citations and continues to increase as new articles appear

A Three-Dimensional Wireless Indoor Localization System

Directory of Open Access Journals (Sweden)

Ping Yi

2014-01-01

Full Text Available Indoor localization, an emerging technology in location based service (LBS, is now playing a more and more important role both in commercial and in civilian industry. Global position system (GPS is the most popular solution in outdoor localization field, and the accuracy is around 10 meter error in positioning. However, with complex obstacles in buildings, problems rise in the “last mile” of localization field, which encourage a momentum of indoor localization. The traditional indoor localization system is either range-based or fingerprinting-based, which requires a lot of time and efforts to do the predeployment. In this paper, we present a 3-dimensional on-demand indoor localization system (3D-ODIL, which can be fingerprint-free and deployed rapidly in a multistorey building. The 3D-ODIL consists of two phases, vertical localization and horizontal localization. On vertical direction, we propose multistorey differential (MSD algorithm and implement it to fulfill the vertical localization, which can greatly reduce the number of anchors deployed. We use enhanced field division (EFD algorithm to conduct the horizontal localization. EFD algorithm is a range-free algorithm, the main idea of which is to dynamically divide the field within different signature area and position the target. The accuracy and performance have been validated through our extensive analysis and systematic experiments.

A Comprehensive Real-Time Indoor Air-Quality Level Indicator

Directory of Open Access Journals (Sweden)

Jungho Kang

2016-09-01

Full Text Available The growing concern about Indoor Air-Quality has accelerated the development of small, low-cost air-quality monitoring systems. These systems are capable of monitoring various indoor air pollutants in real time, notifying users about the current air-quality status and gathering the information to the central server. However, most Internet of Things (IoT-based air-quality monitoring systems numerically present the sensed value per pollutant, making it difficult for general users to identify how polluted the air is. Therefore, in this paper, we first introduce a tiny air-quality monitoring system that we developed and, based on the system, we also test the applicability of the comprehensive Air-Quality Index (AQI, which is widely used all over the world, in terms of its capacity for a comprehensive indoor air-quality indication. We also develop design considerations for an IoT-based air-quality monitoring system and propose a real-time comprehensive indoor air-quality level indication method, which effectively copes with dynamic changes and is efficient in terms of processing and memory overhead.

Regionalised tertiary psychiatric residential facilities.

Science.gov (United States)

Lesage, Alain; Groden, David; Goldner, Elliot M; Gelinas, Daniel; Arnold, Leslie M

2008-01-01

Psychiatric hospitals remain the main venue for long-term mental health care and, despite widespread closures and downsizing, no country that built asylums in the last century has done away with them entirely--with the recent exception of Italy. Differentiated community-based residential alternatives have been developed over the past decades, with staffing levels that range from full-time professional, to daytime only, to part-time/on-call. This paper reviews the characteristics of community-based psychiatric residential care facilities as an alternative to long-term care in psychiatric hospitals. It describes five factors decision makers should consider: 1. number of residential places needed; 2. staffing levels; 3. physical setting; 4. programming; and 5. governance and financing. In Italy, facilities with full-time professional staff have been developed since the mid-1990s to accommodate the last cohorts of patients discharged from psychiatric hospitals. In the United Kingdom, experiments with hostel wards since the 1980s have shown that home-like, small-scale facilities with intensive treatment and rehabilitation programming can be effective for the most difficult-to-place patients. More recently in Australia, Community Care Units (CCUs) have been applying this concept. In the Canadian province of British Columbia (BC), Tertiary Psychiatric Residential Facilities (TPRFs) have been developed as part of an effort to regionalise health and social services and downsize and ultimately close its only psychiatric hospital. This type of service must be further developed in addition to the need for forensic, acute-care and intermediate-level beds, as well as for community-based care such as assertive community treatment and intensive case management. All these types of services, together with long-term community-based residential care, constitute the elements of a balanced mental health care system. As part of a region's balanced mental health care plan, these Tertiary

Temporal variation of residential pesticide use and comparison of two survey platforms: a longitudinal study among households with young children in Northern California.

Science.gov (United States)

Wu, Xiangmei May; Bennett, Deborah H; Ritz, Beate; Tancredi, Daniel J; Hertz-Picciotto, Irva

2013-08-20

Pesticide use patterns are essential inputs into human pesticide exposure models. Currently, data included for modeling purposes have mostly been collected in cross-sectional surveys. However, it is questionable whether responses to one-time surveys are representative of pesticide use over longer periods, which is needed for assessment of health impact. This study was designed to evaluate population-wide temporal variations and within-household variations in reported residential pesticide use patterns and to compare alternative pesticide data collection methods - web surveys versus telephone interviews. A total of 481 households in Northern California provided up to 3 annual telephone interviews on residential pesticide use; 182 of these households provided up to 6 quarterly web surveys that covered the same topics for some of the same time periods. Information on frequency and areas of application were collected for outdoor and indoor sprays, indoor foggers, professional applications, and behind-the-neck treatments for pets. Population-wide temporal variation and within-household consistency were examined both within telephone surveys and within web surveys, and quantified using Generalized Estimating Equations and Mixed Effect Modeling. Reporting between the two methods, the telephone survey and the web survey, was also compared. Use prevalence of outdoor sprays across the population reported in both the annual telephone surveys and the quarterly web surveys decreased over time, as did behind-the-neck treatment of pets reported in the quarterly web survey. Similarly, frequencies of use of these products decreased in the quarterly web surveys. Indoor sprays showed no statistically significant population-wide temporal variation in either survey. Intraclass correlation coefficients indicated consistent use within a household for behind-the-neck treatment on pets and outdoor sprays but great variability for the use of indoor sprays. Indoor sprays were most

Energy and exergy performance of residential heating systems with separate mechanical ventilation

International Nuclear Information System (INIS)

Zmeureanu, Radu; Yu Wu, Xin

2007-01-01

The paper brings new evidence on the impact of separate mechanical ventilation system on the annual energy and exergy performance of several design alternatives of residential heating systems, when they are designed for a house in Montreal. Mathematical models of residential heating, ventilation and domestic hot water (HVAC-DHW) systems, which are needed for this purpose, are developed and furthermore implemented in the Engineering Equation Solver (EES) environment. The Coefficient of Performance and the exergy efficiency are estimated as well as the entropy generation and exergy destruction of the overall system. The equivalent greenhouse gas emissions due to the on-site and off-site use of primary energy sources are also estimated. The addition of a mechanical ventilation system with heat recovery to any HVAC-DHW system discussed in the paper increases the energy efficiency; however, it decreases the exergy efficiency, which indicates a potential long-term damaging impact on the natural environment. Therefore, the use of a separate mechanical ventilation system in a house should be considered with caution, and recommended only when other means for controlling the indoor air quality cannot be applied

Residential-energy-demand modeling and the NIECS data base: an evaluation

Energy Technology Data Exchange (ETDEWEB)

Cowing, T.G.; Dubin, J.A.; McFadden, D.

1982-01-01

The purpose of this report is to evaluate the 1978-1979 National Interim Energy Consumption Survey (NIECS) data base in terms of its usefulness for estimating residential energy demand models based on household appliance choice and utilization decisions. The NIECS contains detailed energy usage information at the household level for 4081 households during the April 1978 to March 1979 period. Among the data included are information on the structural and thermal characteristics of the housing unit, demographic characteristics of the household, fuel usage, appliance characteristics, and actual energy consumption. The survey covers the four primary residential fuels-electricity, natural gas, fuel oil, and liquefied petroleum gas - and includes detailed information on recent household conservation and retrofit activities. Section II contains brief descriptions of the major components of the NIECS data set. Discussions are included on the sample frame and the imputation procedures used in NIECS. There are also two extensive tables, giving detailed statistical and other information on most of the non-vehicle NIECS variables. Section III contains an assessment of the NIECS data, focusing on four areas: measurement error, sample design, imputation problems, and additional data needed to estimate appliance choice/use models. Section IV summarizes and concludes the report.

Indoor-Outdoor Detection Using a Smart Phone Sensor.

Science.gov (United States)

Wang, Weiping; Chang, Qiang; Li, Qun; Shi, Zesen; Chen, Wei

2016-09-22

In the era of mobile internet, Location Based Services (LBS) have developed dramatically. Seamless Indoor and Outdoor Navigation and Localization (SNAL) has attracted a lot of attention. No single positioning technology was capable of meeting the various positioning requirements in different environments. Selecting different positioning techniques for different environments is an alternative method. Detecting the users' current environment is crucial for this technique. In this paper, we proposed to detect the indoor/outdoor environment automatically without high energy consumption. The basic idea was simple: we applied a machine learning algorithm to classify the neighboring Global System for Mobile (GSM) communication cellular base station's signal strength in different environments, and identified the users' current context by signal pattern recognition. We tested the algorithm in four different environments. The results showed that the proposed algorithm was capable of identifying open outdoors, semi-outdoors, light indoors and deep indoors environments with 100% accuracy using the signal strength of four nearby GSM stations. The required hardware and signal are widely available in our daily lives, implying its high compatibility and availability.

Indoor-Outdoor Detection Using a Smart Phone Sensor

Directory of Open Access Journals (Sweden)

Weiping Wang

2016-09-01

Full Text Available In the era of mobile internet, Location Based Services (LBS have developed dramatically. Seamless Indoor and Outdoor Navigation and Localization (SNAL has attracted a lot of attention. No single positioning technology was capable of meeting the various positioning requirements in different environments. Selecting different positioning techniques for different environments is an alternative method. Detecting the users’ current environment is crucial for this technique. In this paper, we proposed to detect the indoor/outdoor environment automatically without high energy consumption. The basic idea was simple: we applied a machine learning algorithm to classify the neighboring Global System for Mobile (GSM communication cellular base station’s signal strength in different environments, and identified the users’ current context by signal pattern recognition. We tested the algorithm in four different environments. The results showed that the proposed algorithm was capable of identifying open outdoors, semi-outdoors, light indoors and deep indoors environments with 100% accuracy using the signal strength of four nearby GSM stations. The required hardware and signal are widely available in our daily lives, implying its high compatibility and availability.

The right to healthy indoor air: Status by 2002

DEFF Research Database (Denmark)

Mølhave, Lars; Krzyzanowski, M.

2003-01-01

. The discussions and statements are available as a WHO report. It informs the individuals and groups responsible for healthy indoor air about their rights and obligations, and empowers the general public by making people familiar with those rights. One year after their publication the statements have been adopted......One of the reasons for the inadequate quality of indoor air arises from the poor articulation, appreciation and understanding of basic principles underlying the policies and actions related to indoor air quality. A WHO Working Group derived nine statements on rights to healthy indoor air...... as the base for future regulation and guidance. The Board of Directors of the International Society of Indoor Air Quality (ISIAQ) and the participants of two international conferences endorse the use of the statements. No opposition to the statements have been registered. The statements have entered curricula...

Indoor climate design for a monumental building with incidental high indoor moisture loads

NARCIS (Netherlands)

Schijndel, van A.W.M.

2005-01-01

The paper presents a study of the indoor climate of a monumental building with periodic high indoor moisture loads. Several scenarios of the past performance and new control classes are simulated and evaluated. The results include the influence of hygric inertia on the indoor climate and

Bluetooth Indoor Positioning System using Fingerprinting

DEFF Research Database (Denmark)

Frost, Christian; Jensen, Casper Svenning; Luckow, Kasper Søe

2011-01-01

Indoor Positioning has been an active research area in the last decade, but so far, commercial Indoor Positioning Systems (IPSs) have been sparse. The main obstacle towards widely available IPSs has been the lack of appropriate, low cost technologies, that enable indoor positioning. While Wi-Fi...... infrastructures are ubiquitous, consumer-oriented Wi-Fi enabled mobile phones have been missing. Conversely, while Bluetooth technology is present in the vast majority of consumer mobile phones, Bluetooth infrastructures have been missing. Bluetooth infrastructures have typically been installed as part...... of complete hardware/software IPSs that often incur a substantial hardware cost. Furthermore, Bluetooth has low power consumption compared to Wi-Fi devices, which promotes longer battery life-time on mobile phones. In this paper, we present a Bluetooth IPS based entirely on commodity-grade products...

Behavior Analysis of Novel Wearable Indoor Mapping System Based on 3D-SLAM.

Science.gov (United States)

Lagüela, Susana; Dorado, Iago; Gesto, Manuel; Arias, Pedro; González-Aguilera, Diego; Lorenzo, Henrique

2018-03-02

This paper presents a Wearable Prototype for indoor mapping developed by the University of Vigo. The system is based on a Velodyne LiDAR, acquiring points with 16 rays for a simplistic or low-density 3D representation of reality. With this, a Simultaneous Localization and Mapping (3D-SLAM) method is developed for the mapping and generation of 3D point clouds of scenarios deprived from GNSS signal. The quality of the system presented is validated through the comparison with a commercial indoor mapping system, Zeb-Revo, from the company GeoSLAM and with a terrestrial LiDAR, Faro Focus 3D X330. The first is considered as a relative reference with other mobile systems and is chosen due to its use of the same principle for mapping: SLAM techniques based on Robot Operating System (ROS), while the second is taken as ground-truth for the determination of the final accuracy of the system regarding reality. Results show that the accuracy of the system is mainly determined by the accuracy of the sensor, with little increment in the error introduced by the mapping algorithm.

Behavior Analysis of Novel Wearable Indoor Mapping System Based on 3D-SLAM

Directory of Open Access Journals (Sweden)

Susana Lagüela

2018-03-01

Full Text Available This paper presents a Wearable Prototype for indoor mapping developed by the University of Vigo. The system is based on a Velodyne LiDAR, acquiring points with 16 rays for a simplistic or low-density 3D representation of reality. With this, a Simultaneous Localization and Mapping (3D-SLAM method is developed for the mapping and generation of 3D point clouds of scenarios deprived from GNSS signal. The quality of the system presented is validated through the comparison with a commercial indoor mapping system, Zeb-Revo, from the company GeoSLAM and with a terrestrial LiDAR, Faro Focus3D X330. The first is considered as a relative reference with other mobile systems and is chosen due to its use of the same principle for mapping: SLAM techniques based on Robot Operating System (ROS, while the second is taken as ground-truth for the determination of the final accuracy of the system regarding reality. Results show that the accuracy of the system is mainly determined by the accuracy of the sensor, with little increment in the error introduced by the mapping algorithm.

Finding dense locations in symbolic indoor tracking data

DEFF Research Database (Denmark)

Ahmed, Tanvir; Pedersen, Torben Bach; Lu, Hua

2017-01-01

presents two graph-based models for constrained and semi-constrained indoor movement, respectively, and then uses the models to map raw tracking records into mapping records that represent object entry and exit times in particular locations. Subsequently, an efficient indexing structure called Hierarchical...... Dense Location Time Index (HDLT-Index) is proposed for indexing the time intervals of the mapping table, along with index construction, query processing, and pruning techniques. The HDLT-Index supports very efficient aggregate point, interval, and duration queries as well as dense location queries......Finding the dense locations in large indoor spaces is very useful for many applications such as overloaded area detection, security control, crowd management, indoor navigation, and so on. Indoor tracking data can be enormous and are not immediately ready for finding dense locations. This paper...

Determining the market value of high-rise residential buildings based on evaluation of consumer properties

Directory of Open Access Journals (Sweden)

Kolobova Svetlana

2018-01-01

Full Text Available As you know, high-rise construction is an indicator of the practical implementation of advanced innovative technologies in the construction industry of the country. High-rise building inevitably comes to the big cities, in connection with the shortage and value of land. The life cycle of any construction project, including high-rise buildings consists of chains: of engineering survey - design-construction-operation. In the process of operation of a tall building, decisions about major repairs or reconstruction of a building are made for decision-making on further use. This article describes methods of assessing the consumer quality of high-rise residential buildings and the establishment of prices based on consumer characteristics of a tall residential building. It is proposed to assess the premises under their quality characteristics. The study was conducted to establish the influence of individual, comprehensive and integral indicators of comparable quality for effective quality living spaces. Simultaneously, there was established a relationship of quality with the consumer cost of housing, ultimately with the potential needs of owners, tenants of the home, lessor dwelling, or buyers of residential properties and other participants in the residential real estate market. This relationship further creates consumer requirements to quality standard of premises at a certain stage of socio-economic development.

Determining the market value of high-rise residential buildings based on evaluation of consumer properties

Science.gov (United States)

Kolobova, Svetlana

2018-03-01

As you know, high-rise construction is an indicator of the practical implementation of advanced innovative technologies in the construction industry of the country. High-rise building inevitably comes to the big cities, in connection with the shortage and value of land. The life cycle of any construction project, including high-rise buildings consists of chains: of engineering survey - design-construction-operation. In the process of operation of a tall building, decisions about major repairs or reconstruction of a building are made for decision-making on further use. This article describes methods of assessing the consumer quality of high-rise residential buildings and the establishment of prices based on consumer characteristics of a tall residential building. It is proposed to assess the premises under their quality characteristics. The study was conducted to establish the influence of individual, comprehensive and integral indicators of comparable quality for effective quality living spaces. Simultaneously, there was established a relationship of quality with the consumer cost of housing, ultimately with the potential needs of owners, tenants of the home, lessor dwelling, or buyers of residential properties and other participants in the residential real estate market. This relationship further creates consumer requirements to quality standard of premises at a certain stage of socio-economic development.

Health effects of indoor odorants.

Science.gov (United States)

Cone, J E; Shusterman, D

1991-11-01

People assess the quality of the air indoors primarily on the basis of its odors and on their perception of associated health risk. The major current contributors to indoor odorants are human occupant odors (body odor), environmental tobacco smoke, volatile building materials, bio-odorants (particularly mold and animal-derived materials), air fresheners, deodorants, and perfumes. These are most often present as complex mixtures, making measurement of the total odorant problem difficult. There is no current method of measuring human body odor, other than by human panel studies of expert judges of air quality. Human body odors have been quantitated in terms of the "olf" which is the amount of air pollution produced by the average person. Another quantitative unit of odorants is the "decipol," which is the perceived level of pollution produced by the average human ventilated by 10 L/sec of unpolluted air or its equivalent level of dissatisfaction from nonhuman air pollutants. The standard regulatory approach, focusing on individual constituents or chemicals, is not likely to be successful in adequately controlling odorants in indoor air. Besides the current approach of setting minimum ventilation standards to prevent health effects due to indoor air pollution, a standard based on the olf or decipol unit might be more efficacious as well as simpler to measure.

Analysis and Design of Timing Recovery Schemes for DMT Systems over Indoor Power-Line Channels

Directory of Open Access Journals (Sweden)

Cortés José Antonio

2007-01-01

Full Text Available Discrete multitone (DMT modulation is a suitable technique to cope with main impairments of broadband indoor power-line channels: spectral selectivity and cyclic time variations. Due to the high-density constellations employed to achieve the required bit-rates, synchronization issues became an important concern in these scenarios. This paper analyzes the performance of a conventional DMT timing recovery scheme designed for linear time-invariant (LTI channels when employed over indoor power lines. The influence of the channel cyclic short-term variations and the sampling jitter on the system performance is assessed. Bit-rate degradation due to timing errors is evaluated in a set of measured channels. It is shown that this synchronization mechanism limits the system performance in many residential channels. Two improvements are proposed to avoid this end: a new phase error estimator that takes into account the short-term changes in the channel response, and the introduction of notch filters in the timing recovery loop. Simulations confirm that the new scheme eliminates the bit-rate loss in most situations.

Phytoforensics: Trees as bioindicators of potential indoor exposure via vapor intrusion.

Directory of Open Access Journals (Sweden)

Jordan L Wilson

Full Text Available Human exposure to volatile organic compounds (VOCs via vapor intrusion (VI is an emerging public health concern with notable detrimental impacts on public health. Phytoforensics, plant sampling to semi-quantitatively delineate subsurface contamination, provides a potential non-invasive screening approach to detect VI potential, and plant sampling is effective and also time- and cost-efficient. Existing VI assessment methods are time- and resource-intensive, invasive, and require access into residential and commercial buildings to drill holes through basement slabs to install sampling ports or require substantial equipment to install groundwater or soil vapor sampling outside the home. Tree-core samples collected in 2 days at the PCE Southeast Contamination Site in York, Nebraska were analyzed for tetrachloroethene (PCE and results demonstrated positive correlations with groundwater, soil, soil-gas, sub-slab, and indoor-air samples collected over a 2-year period. Because tree-core samples were not collocated with other samples, interpolated surfaces of PCE concentrations were estimated so that comparisons could be made between pairs of data. Results indicate moderate to high correlation with average indoor-air and sub-slab PCE concentrations over long periods of time (months to years to an interpolated tree-core PCE concentration surface, with Spearman's correlation coefficients (ρ ranging from 0.31 to 0.53 that are comparable to the pairwise correlation between sub-slab and indoor-air PCE concentrations (ρ = 0.55, n = 89. Strong correlations between soil-gas, sub-slab, and indoor-air PCE concentrations and an interpolated tree-core PCE concentration surface indicate that trees are valid indicators of potential VI and human exposure to subsurface environment pollutants. The rapid and non-invasive nature of tree sampling are notable advantages: even with less than 60 trees in the vicinity of the source area, roughly 12 hours of tree

Phytoforensics: Trees as bioindicators of potential indoor exposure via vapor intrusion.

Science.gov (United States)

Wilson, Jordan L; Samaranayake, V A; Limmer, Matt A; Burken, Joel G

2018-01-01

Human exposure to volatile organic compounds (VOCs) via vapor intrusion (VI) is an emerging public health concern with notable detrimental impacts on public health. Phytoforensics, plant sampling to semi-quantitatively delineate subsurface contamination, provides a potential non-invasive screening approach to detect VI potential, and plant sampling is effective and also time- and cost-efficient. Existing VI assessment methods are time- and resource-intensive, invasive, and require access into residential and commercial buildings to drill holes through basement slabs to install sampling ports or require substantial equipment to install groundwater or soil vapor sampling outside the home. Tree-core samples collected in 2 days at the PCE Southeast Contamination Site in York, Nebraska were analyzed for tetrachloroethene (PCE) and results demonstrated positive correlations with groundwater, soil, soil-gas, sub-slab, and indoor-air samples collected over a 2-year period. Because tree-core samples were not collocated with other samples, interpolated surfaces of PCE concentrations were estimated so that comparisons could be made between pairs of data. Results indicate moderate to high correlation with average indoor-air and sub-slab PCE concentrations over long periods of time (months to years) to an interpolated tree-core PCE concentration surface, with Spearman's correlation coefficients (ρ) ranging from 0.31 to 0.53 that are comparable to the pairwise correlation between sub-slab and indoor-air PCE concentrations (ρ = 0.55, n = 89). Strong correlations between soil-gas, sub-slab, and indoor-air PCE concentrations and an interpolated tree-core PCE concentration surface indicate that trees are valid indicators of potential VI and human exposure to subsurface environment pollutants. The rapid and non-invasive nature of tree sampling are notable advantages: even with less than 60 trees in the vicinity of the source area, roughly 12 hours of tree-core sampling with minimal

Phytoforensics: Trees as bioindicators of potential indoor exposure via vapor intrusion

Science.gov (United States)

Wilson, Jordan L.; Samaranayake, V.A.; Limmer, Matthew A.; Burken, Joel G.

2018-01-01

Human exposure to volatile organic compounds (VOCs) via vapor intrusion (VI) is an emerging public health concern with notable detrimental impacts on public health. Phytoforensics, plant sampling to semi-quantitatively delineate subsurface contamination, provides a potential non-invasive screening approach to detect VI potential, and plant sampling is effective and also time- and cost-efficient. Existing VI assessment methods are time- and resource-intensive, invasive, and require access into residential and commercial buildings to drill holes through basement slabs to install sampling ports or require substantial equipment to install groundwater or soil vapor sampling outside the home. Tree-core samples collected in 2 days at the PCE Southeast Contamination Site in York, Nebraska were analyzed for tetrachloroethene (PCE) and results demonstrated positive correlations with groundwater, soil, soil-gas, sub-slab, and indoor-air samples collected over a 2-year period. Because tree-core samples were not collocated with other samples, interpolated surfaces of PCE concentrations were estimated so that comparisons could be made between pairs of data. Results indicate moderate to high correlation with average indoor-air and sub-slab PCE concentrations over long periods of time (months to years) to an interpolated tree-core PCE concentration surface, with Spearman’s correlation coefficients (ρ) ranging from 0.31 to 0.53 that are comparable to the pairwise correlation between sub-slab and indoor-air PCE concentrations (ρ = 0.55, n = 89). Strong correlations between soil-gas, sub-slab, and indoor-air PCE concentrations and an interpolated tree-core PCE concentration surface indicate that trees are valid indicators of potential VI and human exposure to subsurface environment pollutants. The rapid and non-invasive nature of tree sampling are notable advantages: even with less than 60 trees in the vicinity of the source area, roughly 12 hours of tree-core sampling with

Indoor Air Quality and Asthma

Directory of Open Access Journals (Sweden)

Robert Golden

2017-02-01

Full Text Available Numerous contaminants in indoor air and their potential to cause or exacerbate asthma continue to be a subject of public health concern. Many agents are causally associated with or can exacerbate asthma, particularly in children. For formaldehyde, an established respiratory irritant based on numerous studies, the evidence for an association with asthma is still considered only limited or suggestive. However, there is no evidence that indicates increased sensitivity to sensory irritation to formaldehyde in people often regarded as susceptible such as asthmatics. Acrolein, but not formaldehyde, was significantly associated with asthma in a large cohort of children. This prompted an evaluation of this highly irritating chemical that had never previously been considered in the context of the indoor air/childhood asthma issue. Because acrolein is more potent than formaldehyde as a respiratory irritant and ubiquitous in indoor air, it is plausible that previous studies on potential risk factors and childhood asthma may be confounded by formaldehyde acting as an unrecognized proxy for acrolein.

EML indoor radon workshop, 1982

International Nuclear Information System (INIS)

George, A.C.; Lowder, W.; Fisenne, I.; Knutson, E.O.; Hinchliffe, L.

1983-07-01

A workshop on indoor radon, held at the Environmental Measurements Laboratory (EML) on November 30 and December 1, 1982, covered recent developments in radon daughter research and development. Thirty papers were presented dealing with standardization and quality assurance measurement methods, surveys, measurements strategy, physical mechanisms of radon and radon daughter transport and development of guidance standards for indoor exposures. The workshop concluded with a planning session that identified the following needs: (1) national and international intercomparisons of techniques for measuring radon and radon daughter concentrations, working level and radon exhalation flux density; (2) development and refinement of practical measurement techniques for thoron and its daughter products; (3) quantitative definition of the sources of indoor radon and the mechanisms of transport into structures; (4) better knowledge of the physical properties of radon daughters; (5) more complete and accurate data on the population exposure to radon, which can only be met by broadly based surveys; and (6) more international cooperation and information exchange among countries with major research programs

A proposed UAV for indoor patient care.

Science.gov (United States)

Todd, Catherine; Watfa, Mohamed; El Mouden, Yassine; Sahir, Sana; Ali, Afrah; Niavarani, Ali; Lutfi, Aoun; Copiaco, Abigail; Agarwal, Vaibhavi; Afsari, Kiyan; Johnathon, Chris; Okafor, Onyeka; Ayad, Marina

2015-09-10

Indoor flight, obstacle avoidance and client-server communication of an Unmanned Aerial Vehicle (UAV) raises several unique research challenges. This paper examines current methods and associated technologies adapted within the literature toward autonomous UAV flight, for consideration in a proposed system for indoor healthcare administration with a quadcopter. We introduce Healthbuddy, a unique research initiative towards overcoming challenges associated with indoor navigation, collision detection and avoidance, stability, wireless drone-server communications and automated decision support for patient care in a GPS-denied environment. To address the identified research deficits, a drone-based solution is presented. The solution is preliminary as we develop and refine the suggested algorithms and hardware system to achieve the research objectives.

On Calibrating the Sensor Errors of a PDR-Based Indoor Localization System

Directory of Open Access Journals (Sweden)

Wen-Yuah Shih

2013-04-01

Full Text Available Many studies utilize the signal strength of short-range radio systems (such as WiFi, ultrasound and infrared to build a radio map for indoor localization, by deploying a large number of beacon nodes within a building. The drawback of such an infrastructure-based approach is that the deployment and calibration of the system are costly and labor-intensive. Some prior studies proposed the use of Pedestrian Dead Reckoning (PDR for indoor localization, which does not require the deployment of beacon nodes. In a PDR system, a small number of sensors are put on the pedestrian. These sensors (such as a G-sensor and gyroscope are used to estimate the distance and direction that a user travels. The effectiveness of a PDR system lies in its success in accurately estimating the user’s moving distance and direction. In this work, we propose a novel waist-mounted based PDR that can measure the user’s step lengths with a high accuracy. We utilize vertical acceleration of the body to calculate the user’s change in height during walking. Based on the Pythagorean Theorem, we can then estimate each step length using this data. Furthermore, we design a map matching algorithm to calibrate the direction errors from the gyro using building floor plans. The results of our experiment show that we can achieve about 98.26% accuracy in estimating the user’s walking distance, with an overall location error of about 0.48 m.

Evaporative Cooler Use Influences Temporal Indoor Relative Humidity but Not Dust Mite Allergen Levels in Homes in a Semi-Arid Climate.

Directory of Open Access Journals (Sweden)

James D Johnston

Full Text Available Concerns about energy consumption and climate change make residential evaporative coolers a popular alternative to central air conditioning in arid and semi-arid climates. However, evaporative coolers have been shown to significantly increase indoor relative humidity and dust mite allergen levels in some studies, while showing no association in other studies. Improved measurement of temporal fluctuations in indoor relative humidity may help identify factors that promote mite growth in homes in dry climates. Dust samples and continuous indoor relative humidity measurements were collected from homes with central air conditioning and homes with evaporative coolers in Utah. Samples were collected over two seasons, winter/spring (Jan-Apr and summer (July-Sept, 2014. Dust samples were analyzed for Der p 1 and Der f 1 using a two-site monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA analysis. Housing characteristics including age of home, occupant density, and age of mattresses, furniture, and carpeting were also measured. Positive Der p 1 or Der f 1 samples were found in 25.0% of the homes and there was no difference in mean allergen levels by type of air conditioning. Indoor relative humidity was significantly higher in homes with evaporative coolers compared to those with central air conditioning during the summer. Homes with evaporative coolers also spent significantly more time during summer above 55.0% and 65.0% relative humidity compared to central air homes, but not above 75.0%. Findings from this study suggest that increased humidity from evaporative coolers may not be sufficient to exceed the critical equilibrium humidity or maintain humidity excursions for sufficient duration in relatively larger single-family homes in semi-arid climates to support mite growth and reproduction.

A Middleware Based Approach to Dynamically Deploy Location Based Services onto Heterogeneous Mobile Devices Using Bluetooth in Indoor Environment

Science.gov (United States)

Sadhukhan, Pampa; Sen, Rijurekha; Das, Pradip K.

Several methods for providing location based service (LBS) to mobile devices in indoor environment using wireless technologies like WLAN, RFID and Bluetooth have been proposed, implemented and evaluated. However, most of them do not focus on heterogeneity of mobile platforms, memory constraint of mobile devices, the adaptability of client or device to the new services it discovers whenever it reaches a new location. In this paper, we have proposed a Middleware based approach of LBS provision in the indoor environment, where a Bluetooth enabled Base Station (BS) detects Bluetooth enabled mobile devices and pushes a proper client application only to those devices that belong to some registered subscriber of LBS. This dynamic deployment enables the mobile clients to access any new service without having preinstalled interface to that service beforehand and thus the client's memory consumption is reduced. Our proposed work also addresses the other issues like authenticating the clients before providing them LBSs and introducing paid services. We have evaluated its performance in term of file transfer time with respect to file size and throughput with respect to distance. Experimental results on service consumption time by the mobile client for different services are also presented.

Critical analysis about solutions and models of solar shades in non-residential buildings from tropical regions.

Science.gov (United States)

Castañon, J A B; Caldeira, L F D; Gervásio, M F; Brum, F M

2012-01-01

Whereas the non-residential buildings consume a significant percentage of the total energy produced by the city, is important that these buildings have for such consumption is reduced or consumed in a conscious way. To do so, using concepts of energy efficiency, this work is to explain passive strategies with the use of flexible solar shades that help to get a favorable outcome with respect to the performance of the building right in the initial stages of planning and design. Once initial gains can be obtained and the architecture constants that value at the same time provide better working conditions and indoor comfort.

Cancer risk disparities between hispanic and non-hispanic white populations: the role of exposure to indoor air pollution.

Science.gov (United States)

Hun, Diana E; Siegel, Jeffrey A; Morandi, Maria T; Stock, Thomas H; Corsi, Richard L

2009-12-01

Hispanics are the fastest growing minority group in the United States; however, minimal information is available on their cancer risks from exposures to hazardous air pollutants (HAPs) and how these risks compare to risks to non-Hispanic whites. We estimated the personal exposure and cancer risk of Hispanic and white adults who participated in the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study. We evaluated 12 of the sampled volatile organic compounds and carbonyls and identified the HAPs of most concern and their possible sources. Furthermore, we examined sociodemographic factors and building characteristics. Cumulative cancer risks (CCRs) estimated for Hispanics (median = 519 x 10(-6), 90th percentile = 3,968 x 10(-6)) and for whites (median = 443 x 10(-6), 90th percentile = 751 x 10(-6)) were much greater than the U.S. Environmental Protection Agency (EPA) benchmark of 10(-6). Cumulative risks were dominated by formaldehyde and p-dichlorobenzene (p-DCB) and, to a lesser extent, by acetaldehyde, chloroform, and benzene. Exposure to all of these compounds except benzene was primarily due to indoor residential sources. Hispanics had statistically higher CCRs than did whites (p indoors increased in houses with lower ventilation rates. Hispanics appear to be disproportionately affected by certain HAPs from indoor and outdoor sources. Policies that aim to reduce risk from exposure to HAPs for the entire population and population subgroups should consider indoor air pollution.

Ozone-surface interactions: Investigations of mechanisms, kinetics, mass transport, and implications for indoor air quality

Energy Technology Data Exchange (ETDEWEB)

Morrison, Glenn Charles [Univ. of California, Berkeley, CA (United States)

1999-12-01

In this dissertation, results are presented of laboratory investigations and mathematical modeling efforts designed to better understand the interactions of ozone with surfaces. In the laboratory, carpet and duct materials were exposed to ozone and measured ozone uptake kinetics and the ozone induced emissions of volatile organic compounds. To understand the results of the experiments, mathematical methods were developed to describe dynamic indoor aldehyde concentrations, mass transport of reactive species to smooth surfaces, the equivalent reaction probability of whole carpet due to the surface reactivity of fibers and carpet backing, and ozone aging of surfaces. Carpets, separated carpet fibers, and separated carpet backing all tended to release aldehydes when exposed to ozone. Secondary emissions were mostly n-nonanal and several other smaller aldehydes. The pattern of emissions suggested that vegetable oils may be precursors for these oxidized emissions. Several possible precursors and experiments in which linseed and tung oils were tested for their secondary emission potential were discussed. Dynamic emission rates of 2-nonenal from a residential carpet may indicate that intermediate species in the oxidation of conjugated olefins can significantly delay aldehyde emissions and act as reservoir for these compounds. The ozone induced emission rate of 2-nonenal, a very odorous compound, can result in odorous indoor concentrations for several years. Surface ozone reactivity is a key parameter in determining the flux of ozone to a surface, is parameterized by the reaction probability, which is simply the probability that an ozone molecule will be irreversibly consumed when it strikes a surface. In laboratory studies of two residential and two commercial carpets, the ozone reaction probability for carpet fibers, carpet backing and the equivalent reaction probability for whole carpet were determined. Typically reaction probability values for these materials were 10