Occupation Location Research Articles

Staphylococcus aureus in two municipal abattoirs in Nigeria: Risk perception, spread and public health implications

Staphylococcus aureus is a zoonotic pathogen of significant public health concern. Information on the prevalence and risk factors facilitating bacterial colonization and spread under abattoir settings in Nigeria are scarce. This cross-sectional study was designed to determine prevalence of S. aureus as well as risk factors on knowledge and practices facilitating pathogen carriage among workers and slaughter animals in two municipal abattoirs of Ilorin and Ibadan, Nigeria. Swab samples (n = 1671) from nostrils of cattle, goats, pigs and abattoir workers, and from meat tables and abattoir walls were collected for detection of S. aureus. A questionnaire was administered to 275 workers to elucidate risk factors of pathogen carriage applying a logistic regression model. S. aureus prevalence was 6.5%. In total, MSSA and MRSA were detected at a frequency of 5.4% and 1.1%. Molecular analysis of the isolates revealed 19 different spa types, including a novel spa type (t16751). Gender, marital status, occupation and abattoir location were factors influencing worker’s practices in relation to pathogen carriage and spread in the abattoir setting. This present study detected not only low MSSA and MRSA prevalence, in both abattoirs but also low risk perception and hygiene practices employed by abattoir workers. Good practices among workers at Nigerian abattoirs are needed to mitigate S. aureus carriage. Further studies expounding the antibiotic resistance and relationships of MSSA and MRSA strains detected in this study are needed to complement understanding of the spread of S. aureus in the abattoir food chain.

Improving sparsity and new user problems in collaborative filtering by clustering the personality factors

In collaborative filtering recommender systems, items recommended to an active user are selected based on the interests of users similar to him/her. Collaborative filtering systems suffer from the ‘sparsity’ and ‘new user’ problems. The former refers to the insufficiency of data about users’ preferences and the latter addresses the lack of enough information about the new-coming user. Clustering users is an effective way to improve the performance of collaborative filtering systems in facing the aforementioned problems. In previous studies, users were clustered based on characteristics such as ratings given by them as well as their age, gender, occupation, and geographical location. On the other hand, studies show that there is a significant relationship between users’ personality traits and their interests. To alleviate the sparsity and new user problems, this paper presents a new collaborative filtering system in which users are clustered based on their ‘personality traits’. In the proposed method, the personality of each user is described according to the big-5 personality model and users with similar personality are placed in the same cluster using K-means algorithm. The unknown ratings of the sparse user-item matrix are then estimated based on the clustered users, and recommendations are found for a new user according to a user-based approach which relays on the interests of the users with similar personality to him/her. In addition, for an existing user in the system, recommendations are offered in an item-based approach in which the similarity of items is estimated based on the ratings of users similar to him/her in personality. The proposed method is compared to some former collaborative filtering systems. The results demonstrate that in facing the data sparsity and new user problems, this method reduces the mean absolute error and improves the precision of the recommendations.

面向室内定位的WIFI探针数据预处理研究

为验证依据多探针同时感知到的同一WIFI终端的RSSI值辨识WIFI终端是否在指定区域内的可行性，本文围绕多探针数据集的构造将将WIFI终端数据预处理流程划分为探针探测数据集解析、探针探测数据时间帧编号、面向室内人员定位的探针数据构造等三个阶段，并设计了相关预处理任务的流程并进行了实现。实验结果表明，以预处理后的数据为输入，基于BP神经网络的判别器可以以很高的准确率判别WIFI终端是否在指定的区域内，依据多探针同时感知到的同一WIFI终端的RSSI值辨识WIFI终端是否在指定区域内是可行的。 To verify the feasibility of identifying whether a WIFI terminal is within a designated indoor area based on RSSI value collected by multi WIFI detector, data preprocessing task for the construc-tion of detection data set is divided into three phase such as WIFI probe data parsing, time frame Numbering for probe data and the construction of indoor occupant location oriented data set in this paper. Flow charts for those three phases are given. In this paper, a BP neural network based discriminator for the identification that whether a WIFI terminal is within a designated indoor area is implemented with multi RSSI vector as input. And experimental results show that the precision of the discriminator for indoor area location is high. It is feasibility of identifying whether a WIFI terminal is within a designated indoor area based on multi RSSI detected.

The innovation scorecard for continuous improvement applied to translational science.

This paper reports on the baseline stage of a qualitative evaluation of the application of the Innovative Scorecard (ISC) to the Clinical and Translational Science Award (CTSA) at the University of Texas Medical Branch (UTMB) at Galveston. The ISC is adopted from the established Balanced Scorecard system for strategic planning and performance management. In formulating the evaluation, we focused on the organizational identity literature. The initial evaluation consisted of a series of semi-structured interviews with 22 participants of the ISC Boot Camp conducted in July 2015. The logic of grounded theory pointed to the clustering of perceptions of the ISC around respondents' occupational locations at UTMB. Administrators anticipate the expansion of planning activities to include a wider range of participants under the current CTSA award period (2015-2020) than under our first CTSA approval period (2009-2014). A common viewpoint among the senior scientists was that the scientific value of their work will continue to speak for itself without requiring the language of business. Junior scientists looked forward to the ISC's emphasis on increasingly horizontal leadership that will give them more access to and more control over their work and resources. Postdocs and senior staff welcomed increased involvement in the total research process at UTMB. The report concludes with strategies for future follow-up.

Socio-demography and clinical profile of venous ulcers

Abstract Introduction Venous ulcers are the most common type of non-healing ulcers. They constitute 70% of the chronic leg ulcers. They have significant socioeconomic and psychological consequences reducing the quality of life. There are few Indian studies documenting the extent of the disease Methods All patients with chronic venous ulcers of duration more than 6 months were included from January 2014 to July 2015. Their socio-demographic data such as age, sex, education, occupation, income, socioeconomic status and residential geographic location were documented. Clinical information included size of the ulcer, duplex findings were also noted. Results There were 217 patients. There was male preponderance m: f (8.4:1). Most of them belonged to the economically productive age group of 36 to 45 years and belonged to the middle socioeconomic group. Perforator incompetence was noted to be common in all patients. Conclusions Venous ulcers are common in India. They affect middle age group men predominantly and also belonging to the middle socio-economic group.

Reservation Wages and the Unemployment of Older Workers

Our purpose is to examine the level of reservation wages among older unemployed (45+), and investigate what happens to the level of reservation wages as the length of unemployment increases. Using data from questionnaires completed by unemployed, we examined the reservation wages of 364 individuals and asked whether they would be willing to compromise in terms of their occupation, profession or geographic location to find a job. 112 of the participants responded to two questionnaires over a three-month period to determine the changes in their expectations over time. Additionally, we conducted qualitative interviews with 10 unemployed. We found that older people experienced longer periods of unemployment, and had a greater willingness to reduce salary expectations. The study establishes an innovative connection between older unemployed, reservation wages and the duration of unemployment, showing that higher reservation wages among older unemployed is the cause of prolonging their unemployment.

Multi-mode ventilation: An efficient ventilation strategy for changeable scenarios and energy saving

The advanced air distribution methods such as displacement ventilation and personalized ventilation attempt to seek a balance between better indoor air environment and energy efficiency. However, multiple demand scenarios including variable locations of occupants and indoor sources may exist in daily operation of the ventilation system. Most of existing airflow patterns are single mode and cannot always be efficient when responding to changeable scenarios. In this paper, a novel ventilation strategy, i.e., multi-mode ventilation (MMV), is proposed to address multiple scenarios. MMV is designed by the combination of several single airflow patterns and aims to utilize the individual advantages of each airflow pattern in controlling specific scenarios. The energy saving potential of MMV is demonstrated by numerical studies of a meeting room. An indexed local cooling load (LCL) is adopted to evaluate the performance of airflow patterns. As a key parameter in LCL calculation, the required supply temperature to maintain the set temperature at the target zone is determined by computational fluid dynamics (CFD) method. The results show that each single airflow pattern can only be efficient for part of 8 scenarios. MMV performs better by combining single airflow patterns 1 and 2 regardless of the changes of the location and magnitude of the occupied zone as well as the location of the heat source. MMV achieves a reduction rate of up to 56.8% in cooling load compared with airflow pattern 4. MMV may provide a reference for real projects in controlling temperature, humidity and contaminant concentration under changeable scenarios.

Comparison of Mental Health Status of People Exposed to Noise Pollution with People in Non-Polluted Areas of Sari

Noise pollution in psychological terms is defined as an unpleasant, undesirable or unwanted sound and in quantitative terms, it is a sound possessing all different wavelengths and intensities with no certain combination which is unpleasant to ear. The present study was conducted to compare the mental health status of people exposed to noise pollution with people in non-polluted areas of Sari. The sample population in the present descriptive study included 200 people selected by Random sampling method. Then, Sari was divided into four areas in terms of noise pollution, and after implementing GHQ-28 questionnaire (which reliability and validity have been confirmed), general health as well as mental health of samples were compared with each other. Data analysis was conducted based on occupation and residence location using variance analysis tests and t-Test for quantitative data and Square-test for qualitative data. Complaints about physical difficulties in traders’ group working in non-polluted environment are lower than traders’ group working in an environment exposed to noise pollution. These complaints among residents in non-polluted areas are at the lowest level. In overall review, the prevalence and average of mental health disorders amongst traders in areas exposed to noise pollution are higher than traders in non-polluted areas. Average complaints about physical difficulties, anxiety and sleeping problems, problems with social performance, depression and in general average mental and physical disorders are higher in resident and working groups in areas exposed to noise pollution, however, only complaints about physical difficulties are statistically significant.

Indoor localisation through object detection within multiple environments utilising a single wearable camera

The recent growth in the wearable sensor market has stimulated new opportunities within the domain of Ambient Assisted Living, providing unique methods of collecting occupant information. This approach leverages contemporary wearable technology, Google Glass, to facilitate a unique first-person view of the occupants immediate environment. Machine vision techniques are employed to determine an occupant’s location via environmental object detection. This method provides additional secondary benefits such as first person tracking within the environment and lack of required sensor interaction to determine occupant location. Object recognition is performed using the Oriented Features from Accelerated Segment Test and Rotated Binary Robust Independent Elementary Features algorithm with a K-Nearest Neighbour matcher to match the saved key-points of the objects to the scene. To validate the approach, an experimental set-up consisting of three ADL routines, each containing at least ten activities, ranging from drinking water to making a meal were considered. Ground truth was obtained from manually annotated video data and the approach was previously benchmarked against a common method of indoor localisation that employs dense sensor placement in order to validate the approach resulting in a recall, precision, and F-measure of 0.82, 0.96, and 0.88 respectively. This paper will go on to assess to the viability of applying the solution to differing environments, both in terms of performance and along with a qualitative analysis on the practical aspects of installing such a system within differing environments.

‘Making space public’ through occupation: The Aboriginal Tent Embassy, Canberra

Through the actions of activists involved in the Arab Spring uprisings, European anti-austerity movements and the Occupy and Umbrella movements among others, long-term occupations of public space have re-entered the repertoire of insurgent social movements to spectacular effect. These events have dramatised the challenges and limits of occupation as a spatial strategy for ‘making space public’. This paper seeks to make a contribution to the critical geographical literatures on occupation and public space, through analysis of the Aboriginal Tent Embassy – a politically motivated occupation of a patch of land in the Australian capital that is now entering its 45th year. The Embassy activists mobillised occupation in the process of making and sustaining a counterpublic. Counterpublic participants face a distinct set of geographical challenges in making space for both withdrawal and representation in the face of spatial subordination. Occupations like the Embassy seek to resolve these challenges by combining both of these activities in a single site. The Embassy draws our attention to two important sets of issues in relation to the counterpublic geography of occupations. First, it has much to teach about how space is made public through occupation, including dynamics related to the location, duration, reproduction and relations of occupation. Second, the Embassy issues a challenge about whose space is made public through occupation – as an embodied enactment of indigenous sovereignty, the Embassy reminds us that democratic politics in settler colonial nations like Australia is premised on a violent dispossession that has yet to be fully acknowledged or addressed.

Design methodology for crash occupant protection in cabin design of the high speed vessel

Expansion of marine transport and growing number of high speed vessels travelling in the neighbourhood of the coastline significantly increase the risk of the crash on the sea. Within the existing high speed craft legislations there are no regulations related to prediction of the vessel occupants injury and trauma. Former research has exposed the similarities between the high speed vessel crash and automotive collision enabling the transfer of advanced crash safety technologies between the automotive and marine.This paper investigates the application of the most recent CAE automotive safety technologies to predict the injuries of high speed Cruise Logistics Ferry (CLF) occupants in 40 knots crash with a harbour peer. At first, the probability of occupant injuries was studied using a 50th percentile HYBRID III standing crash test dummy model. The study considered various occupant positions within the boat cabin for two different cabin orientations. The investigation was then followed by computer analyses utilising the state of the art Total Human computer Model for Safety (THUMS) to evaluate the localised passenger traumatology. This model is the most advanced human computer model available, capable of computing injury risks at organ levels.Results from the analyses using both models showed that the standing HYBRID III dummy was suitable to assess the overall risk of occupants' injuries in a cabin design context, while the THUMS model added detailed trauma injuries for selected occupant locations. The results of both investigation indicated very high risk of life changing injuries or even death to the boat occupant within the cabin.A strong relationship between the probability of severe injury and the distance between the passenger and any obstacle in the cabin was found. In conclusion, the research is proposing a design methodology for cabin occupant protection based on the location of each individual passenger relative to obstacles and the associate risk of injury. This is in stark contrast to the general design guidelines of the High Speed Craft code (2000) which are based on threshold values of a global collision design acceleration.

Quantitative evaluation of the occupant kinematic response of the THUMS 50th-percentile male model relative to PMHS laboratory rollover tests

ABSTRACTObjective: The objective of the current study was to evaluate the whole-body kinematic response of the Total Human Model for Safety (THUMS) occupant model in controlled laboratory rollover tests by comparing the model response to postmortem human surrogate (PMHS) kinematic response targets published in 2014.Methods: A computational model of the parametric vehicle buck environment was developed and the AM50 THUMS occupant model (Ver 4.01) was subjected to a pure dynamic roll at 360°/s in trailing-side front-row seating position.A baseline configuration was defined by a baseline posture representing the average of all PMHS postures, with a friction coefficient of 0.4 for the belt and 0.6 for the seat.To encompass challenges in controlling boundary conditions from the PMHS tests and ensure the robustness of the model evaluation, a total of 12 simulations were performed to investigate the following:1. The effect of initial posture by adding 3 additional postures representing PMHS extremes.2. The effect of belt tension by varying tension from the nominal vehicle retractor belt tension of 5 N to the 35 N belt tension used in the PMHS tests.3. The effect of friction between the environment (belt, seat) and THUMS.Trajectories (head, T1, T4, T10, L1, and sacrum), spinal segment rotations (head-to-T1, T1-to-T4, T4-to-T10, T10-to-L1, and L1-to-sacrum) relative to the rollover buck and spinal segment elongation/compression calculated from the simulations were compared to PMHS corridors using a correlation method (CORA).Results: THUMS baseline response showed lower correlation (overall CORA score = 0.63) with the PMHS response in rollover compared to other crash modes. THUMS and PMHS demonstrated similar kinematic responses in the longitudinal axis and vertical axis but significantly different lateral excursion relative to the seat. In addition, no spinal elongation was observed for THUMS compared to the PMHS.The posture, pretension, and belt frictions were found to alter model kinematics, especially on THUMS lateral axis motion. The posture was judged to be the most sensitive parameter evaluated because a change of 30 mm in the lateral axis results in up to an 80 mm of change in observed displacement.Conclusions: Though the model response in the lateral axis is significantly different than that of the PMHS, it is unclear whether this difference is the result of extrinsic factors (posture, pretension, and friction), where exact values in experiment are unknown or by model intrinsic factors (e.g., spine stiffness). These differences in occupant kinematics could potentially subject the PMHS and THUMS to very different loading conditions under roof impact in rollover crashes: different occupant posture and different roof impact location. Therefore, different injury mechanisms and severity might be predicted by the current model relative to the PMHS. Consequently, though the information provided in the current study could be useful for improving model biofidelity for rollover crashes, additional studies are required to properly solve this issue.

Epidemiological study of cutaneous leishmaniasis in southwest of Iran during 2001–2011

ObjectiveTo examine the prevalence process and epidemiological characteristics of cutaneous leishmaniasis (CL) during 2001–2011. MethodsThis was a cross-sectional epidemiologic study examining 2 637 patients with CL in Susangerd county during 2001–2011. The data of all patients who referred to the Prevention Unit of Susangerd Health Center were registered in CL epidemiologic data summary forms. The data and parameters included age, gender, occupation, season, residence (urban, rural), and lesion location. ResultsOut of 2 637 patients, 1 174 cases (44.5%) were females and 1463 patients (55.5%) were males. The maximum rate of infection was recorded in under 10-year-old age group (45.32%) and its minimum rate was seen among those aged over 60 years (0.87%). Among them, 1 557 patients (59.0%) were living in urban and 1 080 (41.0%) were in rural areas. The maximum and minimum occupational frequency distributions were seen in students (49.9%) and farmers (0.6%), respectively. The study showed that the maximum and minimum frequencies were observed in winter (52.33%) and summer (7.62%) correspondingly. The most lesion frequencies from lesion location point of view were related to hands (37.5%), faces (30.0%), feet (26.3%) and other organs (6.2%) and the number of lesions ranged from 1–5 and sized varied from 0.5–5.5 cm ConclusionsEpidemiological parameters such as age, gender, occupation, season, residence (urban, rural) and lesion location in endemic regions have had significant effects on the prevalence of CL in Susangerd county and the findings can be effective for assessing disease prevention programs. In addition, CL might become a serious dermatological health problem in the near future due to a great population movement to the neighboring country Iraq with a high incidence to an endemic area.

Occupational Snake Bites: a Prospective Case Series of Patients Reported to the ToxIC North American Snakebite Registry.

In the developing world, occupation has been identified as a risk factor for snake bite. Such an association has not been described in the USA. The objective of this study was to describe the epidemiology and clinical manifestations of occupational snake bite in patients reported to the ToxIC North American Snakebite Registry (NASBR). This was a prospective case series of patients reported to the ToxIC NASBR between January 1, 2014 and November 5, 2015. Variables collected included snake species, patient demographics, date and location of exposure, occupation, bite location, clinical manifestations, and management. Of 180 adult snake bites reported, 25 (13.9%; 95% CI 9.2-19.8%) were occupational in nature. Rattlesnake envenomations were common (80%). Most snake bites (96%) occurred in men. Occupations most associated with snake bite were landscaping (28%) and working directly with snakes (24%). Fifty-six percent of bites occurred in an outdoor work environment. Seventy-six percent of envenomations were to the upper extremities. Intentional interaction occurred in 40% of cases, all of which sustained finger envenomations. No cases presented with apparent acute ethanol intoxication. The majority of occupational snake bites occurred in men working outdoors and were unintentional injuries. Bites involving the upper extremity tended to result from intentional interactions. Acute ethanol intoxication did not appear to be involved with occupational envenomations.

Willingness-to-Pay for Community-Based Health Insurance among Informal Workers in Urban Bangladesh.

IntroductionReliance on out-of-pocket payment for healthcare may lead poor households to undertake catastrophic health expenditure, and risk-pooling mechanisms have been recommended to mitigate such burdens for households in Bangladesh. About 88% of the population of Bangladesh depends on work in the informal sector. We aimed to estimate willingness-to-pay (WTP) for CBHI and identify its determinants among three categories of urban informal workers rickshaw-pullers, shopkeepers and restaurant workers.MethodsThe bidding game version of contingent valuation method was used to estimate weekly WTP. In three urban locations 557 workers were interviewed using a structured questionnaire during 2010 and 2011. Multiple-regression analysis was used to predict WTP by demographic and household characteristics, occupation, education level and past illness.ResultsWTP for a CBHI scheme was expressed by 86.7% of informal workers. Weekly average WTP was 22.8 BDT [Bangladeshi Taka; 95% confidence interval (CI) 20.9–24.8] or 0.32 USD and varied significantly across occupational groups (p = 0.000) and locations (p = 0.003). WTP was highest among rickshaw-pullers (28.2 BDT or 0.40 USD; 95% CI: 24.7–31.7), followed by restaurant workers (20.4 BDT 0.29 USD; 95% CI: 17.0–23.8) and shopkeepers (19.2 BDT or 0.27 USD; 95% CI: 16.1–22.4). Multiple regression analysis identified monthly income, occupation, geographical location and educational level as the key determinants of WTP. WTP increased 0.196% with each 1% increase in monthly income, and was 26.9% lower among workers with up to a primary level of education versus those with higher than primary, but less than one year of education.ConclusionInformal workers in urban areas thus are willing to pay for CBHI and socioeconomic differences explain the magnitude of WTP. The policy maker might think introducing community-based model including public-community partnership model for healthcare financing of informal workers. Decision making regarding the implementation of such schemes should consider worker location and occupation.

Dear Driver, Could You Enter the Bus Bay Properly?

This study investigated the underlying reasons for the improper use of bus bays in Istanbul, Turkey, one of the megacities in the developing world. Improper use occurs when a bus driver elects to enter a bus bay partially or not at all. Data were compiled from field studies during peak and off-peak hours at three selected bus bays on Buyukdere Street, which was one of the most important urban arterials on the European side of Istanbul. During the field study, information was collected about bus bay use preferences, in addition to data on arrival time, departure time, bus occupancy, number of passengers waiting at a bus stop, illegal parking in the bus bay, and traffic volume on the road. These data were used to estimate three multinomial logit bus bay use models by stratifying the sample with respect to bus bay occupancy and bus stop location. The results showed that illegally parked vehicles were a major factor that led to improper use of bus bays, and the effect was similar to that of the presence of one or more buses in a bus bay on a new bus’s arrival. Moreover, the occupancy of buses was found to be significant because relatively empty buses were more likely not to fully enter a bus bay, whereas packed buses tended toward full use, especially when passengers were alighting at each stop. In terms of policy, it is essential to prevent illegal parking through methods such as the installation of medians. Overall, the study revealed that the success of bus bays was questionable, and the need for them in megacities, such as Istanbul, disputable.

SEXUALLY TRANSMITTED INFECTIONS

Objectives: This study aimed to uncover the trend regarding knowledge aboutsexually transmitted infections (STIs) among Pakistani women of reproductive age 15-49 as wellas evaluating the socio demographic differentials associated with STIs knowledge. Design:The secondary data sets are used of Pakistan demographic and health survey (PDHS) of evermarried women with sample size 10023and 13558.Period: PDHS 2006-07 and PDHS 2012-13.Setting: The national institute of population studies done this survey with the technical supportfrom ICF International and Pakistan bureau of statistics and the USAID supported the financially.Methods: Descriptive frame work along withbivariate analysis was performed to understandthe trend regarding STIs knowledge and evaluate the significant socio demographic factorsrespectively. Results: The awareness regarding STIs and knowledge to use always condomduring sex to reduce the risk of getting HIV/AIDSafter equating the two PDHS has improvedover time just by 3.85% and 6.50% respectively in PDHS-2012-13 compared to PDHS 2006-07.Early age group (15-19) women have sufficient lack of knowledge about STIs. Urban has moreknowledge regarding STIs compared to rural. Education, wealth index and media awarenesshave positive association with STIs knowledge. Conclusions: Socio demographic differentialssuch as age, education, location and geographical area of residence, media access, wealthindex and women occupation are found to be statistically highly significant with respect tosexually transmitted infections knowledge. These statistical outcomes will enhance thecapability in disease management and control.

English

Objectives: This study aimed to uncover the trend regarding knowledge about sexually transmitted infections (STIs) among Pakistani women of reproductive age 15-49 as well as evaluating the socio demographic differentials associated with STIs knowledge. Design: The secondary data sets are used of Pakistan demographic and health survey (PDHS) of ever married women with sample size 10023and 13558.Period: PDHS 2006-07 and PDHS 2012-13. Setting: The national institute of population studies done this survey with the technical support from ICF International and Pakistan bureau of statistics and the USAID supported the financially. Methods: Descriptive frame work along withbivariate analysis was performed to understand the trend regarding STIs knowledge and evaluate the significant socio demographic factors respectively. Results: The awareness regarding STIs and knowledge to use always condom during sex to reduce the risk of getting HIV/AIDSafter equating the two PDHS has improved over time just by 3.85% and 6.50% respectively in PDHS-2012-13 compared to PDHS 2006-07. Early age group (15-19) women have sufficient lack of knowledge about STIs. Urban has more knowledge regarding STIs compared to rural. Education, wealth index and media awareness have positive association with STIs knowledge. Conclusions: Socio demographic differentials such as age, education, location and geographical area of residence, media access, wealth index and women occupation are found to be statistically highly significant with respect to sexually transmitted infections knowledge. These statistical outcomes will enhance the capability in disease management and control.

Indoor Granular Presence Sensing and Control Messaging With an Ultrasonic Circular Array Sensor

Providing automated granular control of lighting, along with user-driven control, results in an energy-efficient smart lighting system design while catering to personal occupant preferences. Two functional ingredients in such a system are: 1) sensing that provides granular information on occupant location and 2) a communication system to transmit control messages from a user. In this paper, we consider an ultrasonic circular array sensor that provides the dual functionality of granular occupant sensing and a communication receiver for user control transmissions. A ceiling-mounted sensor configuration with a colocated ultrasonic transmitter and array receiver is considered. To perform presence sensing, this transmitter sends periodic bursts of sinusoidal pulses that, upon reflection from the environment, are received at the array sensor. The echoes are processed to obtain estimates of range, azimuth, and elevation angles corresponding to possible occupant movements. A Kalman filter based on a near constant velocity model is used for target tracking. The resulting occupant location is used for energy-efficient lighting control. A user may in addition control lamps in its vicinity by sending messages at ultrasonic frequency, which are processed by the receiver array, and used to further adapt requested parameters of the lighting system. The proposed sensing and messaging solution is tested in an indoor office space with an eight-element receiver array sensor prototype.

Modeling, designing, and testing low frequency impact isolation solutions for building structures with fitness centers above grade

There is a trend for fitness centers to find a quick, inexpensive occupancy and ideal location in a vacant office or retail space, often above grade. The tenants sharing the building structure are then subjected to sudden airborne noise and structureborne vibration from the impact energy generated by heavy weights being dropped onto the floor. Because of this trend there is a need to analyze the large, low frequency, shock generated energies that travel through the structure. This paper will discuss the process of designing an experimental floor assembly and apparatus to test weight drops, developing a modeling program to simulate weight drops using three degrees of freedom, which can be tailored to varying isolation solutions, and the means of physically testing the results.