Effect Of Human Movement Research Articles

Review on respiratory infectious disease transmission mechanism: effects of human movement and facemask use

Review on respiratory infectious disease transmission mechanism: effects of human movement and facemask use

Spatial infection control in burn center organization: a burn center design experience for evidence-based architecture

PurposeThis study discusses that the necessary criteria and the solution approach taken to resolve the main spatial infection problems with a burn center design should be evaluated holistically to achieve spatial infection control in a burn center. The burn center design plays an important role in protecting severely burned patients from infection because the microbial flora of the hospital can affect the infection risk. In hospitals, sterilization and disinfection are the basic components of infection prevention; however, the prevention and control of infection for burn patients also requires the design of burn centers that adhere to a specific set of criteria that considers spatial infection control in addition to appropriate burn treatment methods and treatments. In this study, a burn facility converted from a burn unit into a burn center is introduced and the necessary design inputs for the transformation are discussed because there is no holistic study in the literature that delas with all the spaces that should be in a burn center and relations between spaces. This study aims to define the functional relations between each of the units and the spaces that change according to different sterilization demands in the burn center for ensuring spatial infection control. Furthermore, it aims to propose a method for ensuring continuity in the control of spatial infections.Design/methodology/approachThe burn care and health facilities guidelines are examined within the framework of spatial standards, together with a comprehensive literature review. The design method was based on the spread of microorganisms and the effect of human movement on space and spatial transitions in the burn center, according to all relevant literature reviews. To determine the extent to which the differences in treatment protocols of burn care guidelines were reflected in the space, interviews were conducted with burn facility officials. The plan–do–check–act (PDCA) method is also modeled to ensure the continuity of infection control in the burn center.FindingsThe burn center design findings are classified under three main headings, namely, location of the burn center in the hospital, spatial organization and physical features of the burn center and the air flowing system. The importance of the interactions among the criteria for spatial infection control has been revealed. Due to the physical space characteristics and air flow characteristics that change according to human movement and the way microorganisms spread, it has been seen that designing the air flow and architectural aspects together has an effective role in providing spatial infection control. Accordingly, a functional relation scheme for the center has been suggested. It is also proposed as a model to ensure the continuity of infection control in the burn center.Practical implicationsThis research presents spatial measures for infection control in burn centers for practitioners in health-care settings such as designers, engineers, doctors and nurses. The PDCA method also leads to continuity of infection control for hospital management.Originality/valueThis is the first study, to the best of the authors’ knowledge, to focus on developing the criteria for spatial infection control in burn center. Moreover, the aim is to create a function chart that encompasses the relationships between the units within the burn center design so that infection control can be coordinated spatially.

Enhancement effect of human movement on the high risk range of viral aerosols exhaled by a sitting person

Human movement could affect viral aerosol transmission. We carried out full-scale experiments to study the effect of human movement on viral aerosols exhaled by a sitting thermal breathing manikin (STBM), and describe the indoor airflow characteristic. In static scenarios, the aerosol concentration decreased rapidly beyond 1.5 m from a source person. But when a moving manikin (MM) moved in the same direction as STBM's exhalation, forward high risk range Rf extended from 1.5 m to 3.0 m, and lateral range Rl increased from 1.3 m to 2.0 m, referred to as the enhancement effect. Changes in airflow and pressure, air mixing, and the following of aerosols to movement-induced airflow might explain this effect. The airflow velocity v increased when MM passed at 1 m/s, closely related to distance. At the distance 0.25, 0.55 and 1.05 m to MM, v could be up to 0.64, 0.37 and 0.25 m/s, with average value of 0.27 (±0.088), 0.14 (±0.047) and 0.06(±0.039) m/s, respectively. The air continued flowing after MM stopped for more than 30–60 s. Effects related to exhalation direction and ventilation were compared, indicating that the mechanisms of driving lateral and forward transmission might be different. It would be recommended to reduce cross-area walking in areas with epidemic. The increase in ventilation might limit the enhancement effect.

Experimental and numerical simulations of human movement effect on the capture efficiency of a local exhaust ventilation system

In local exhaust ventilation systems, external turbulence from e.g. human movements can affect the capture efficiency of the system considerably. In this study, experimental and numerical (CFD) approaches were utilized to evaluate the effect of human movement on the capture efficiency of a local exhaust ventilation system with an exterior circular hood. Human movements were simulated by back-and-forth movements of three human-sized moving objects: a flat plate (CFD + experimental), a cylinder (CFD) and a human-shaped manikin (CFD), respectively. The experiments consisted of tracer gas measurements in a full-scale test room. The numerical simulations included dynamic mesh methods to handle object movements. The results showed reasonable agreement between numerical and experimental results regarding the capture efficiency at different movement frequencies and exhaust flow rates, indicating that CFD is a feasible method for investigating complex flows of the studied kind. In comparison with the moving manikin, the moving plate caused significantly lower capture efficiency, whereas the moving cylinder yielded higher values. Overall, the results with the cylinder as moving object proved more similar to those of the manikin than the results with the flat plate. These findings have particular relevance towards existing test standards that stipulate the use of a moving flat plate in similar test situations. Further, some parameter variations verified that local exhaust capture efficiency increases by increasing the exhaust air flow rate and movement time interval, and also by decreasing the distance between contaminant source and exhaust hood opening. Also increasing the distance between the movable object and the contaminant source, as well as decreasing the diameter of the exhaust hood opening increased the capture efficiency.

On the Interplay of Regional Mobility, Social Connectedness and The Spread of COVID-19 in Germany

Since the primary mode of respiratory virus transmission is person‐to‐person interaction, we are required to reconsider physical interaction patterns to mitigate the number of people infected with COVID‐19. While research has shown that non‐pharmaceutical interventions (NPI) had an evident impact on national mobility patterns, we investigate the relative regional mobility behaviour to assess the effect of human movement on the spread of COVID‐19. In particular, we explore the impact of human mobility and social connectivity derived from Facebook activities on the weekly rate of new infections in Germany between 3 March and 22 June 2020. Our results confirm that reduced social activity lowers the infection rate, accounting for regional and temporal patterns. The extent of social distancing, quantified by the percentage of people staying put within a federal administrative district, has an overall negative effect on the incidence of infections. Additionally, our results show spatial infection patterns based on geographical as well as social distances.

The effects of human movements on urban climate over Eastern China

We live on an urban planet with unprecedented human mobility. In this study, we collectively analyze ten large cities over densely populated Eastern China, and detect that mass people outflows during Spring Festival (SF) holiday significantly cool down urban climate expressed as urban heat island intensity variation particularly at the nighttime after minimizing the effects of other factors. We estimate that the average nighttime cooling effects of the ten large cities over Eastern China during the SF holiday relative to the nearby background period are 0.63 °C stronger during the 2000s than during the 1990s. The attribution analysis points to that the urban cooling effects are primarily caused by mass people outflows during the SF holiday. Our findings help to better understand the complex interactions of human population dynamics, urban development, and the environment, and may have important implications for promoting sustainable, people-centered, and resilient development of our urban planet.

Impact of People’s Movement on Wi-Fi Link Throughput in Indoor Propagation Environments: An Empirical Study

There has been tremendous growth in the deployment of Wi-Fi 802.11-based networks in recent years. Many researchers have been investigating the performance of the Wi-Fi 802.11-based networks by exploring factors such as signal interference, radio propagation environments, and wireless protocols. However, exploring the effect of people’s movement on the Wi-Fi link throughout the performance is still a potential area yet to be explored. This paper investigates the impact of people’s movement on Wi-Fi link throughput. This is achieved by setting up experimental scenarios by using a pair of wireless laptops to file share where there is human movement between the two nodes. Wi-Fi link throughput is measured in an obstructed office block, laboratory, library, and suburban residential home environments. The collected data from the experimental study show that the performance difference between fixed and random human movement had an overall average of 2.21 ± 0.07 Mbps. Empirical results show that the impact of people’s movement (fixed and random people movements) on Wi-Fi link throughput is insignificant. The findings reported in this paper provide some insights into the effect of human movement on Wi-Fi throughputs that can help network planners for the deployment of next generation Wi-Fi systems.

Effect of daily human movement on some characteristics of dengue dynamics

Human movement is a key factor in infectious diseases spread such as dengue. Here, we explore a mathematical modeling approach based on a system of ordinary differential equations to study the effect of human movement on characteristics of dengue dynamics such as the existence of endemic equilibria, and the start, duration, and amplitude of the outbreak. The model considers that every day is divided into two periods: high-activity and low-activity. Periodic human movement between patches occurs in discrete times. Based on numerical simulations, we show unexpected scenarios such as the disease extinction in regions where the local basic reproductive number is greater than 1. In the same way, we obtain scenarios where outbreaks appear despite the fact that the local basic reproductive numbers in these regions are less than 1 and the outbreak size depends on the length of high-activity and low-activity periods.

Three-dimensional analysis of the effect of human movement on indoor airflow patterns.

Human activity is known to leave significant effects on indoor airflow patterns. These patterns are carefully designed for many facilities such as cleanrooms, pharmaceutical settings, and healthcare environments, where human-induced wakes contribute to the transport of contaminants. Therefore, the knowledge about these wakes as it relates to indoor air quality is critical. As a result, a series of experiments were conducted in a controlled chamber to study the three-dimensional effects of true human walking on airflow. Experiments were designed to capture the effect of human walking under three different flow conditions, and for two different walking schemes. The results show that the effect of walking on the airflow is not negligible and can sustain up to 10seconds after the moving body has passed. Walking on a straight line creates significant change in the velocity normal to the walking path and vertical to the plane of walking movement. These changes were detectable till 1.0m away from the walking track. Also, the similarity between airflow patterns of walking once and twice illustrated a promising opportunity of predicting the flow patterns of random walk from a set of base cases.

An Autonomous RSSI Filtering Method for Dealing with Human Movement Effects in an RSSI-Based Indoor Localization System

In this paper, an experimental evaluation of received signal strength indicator (RSSI-based) localization methods in an indoor wireless network is studied. The major contributions of this work are twofold. First, the well-known and widely used min–max and trilateration methods are tested in the cases of without and with human movement effects. By this purpose, how RSSI data during human movements affect the accuracy of such methods and which method shows the best position estimation result, have been investigated. Second, we also design and develop a new RSSI filter to automatically reduce RSSI variation and the position estimation error caused by human movements. Experiments are carried out in a parking building. An LPC2103F microcontroller interfaced with a CC2500 RF transceiver as a low-cost, low power, 2.4 GHz radio module is used as a wireless node. Results demonstrate that without human movement effects, the performances by both localization methods are not much different. However, with human movement effects, the min–max method shows better accuracy than the trilateration method in handling the RSSI variation problem. The results also indicate that by applying the proposed RSSI filter, it can directly cope with the RSSI variation problem caused by humans. The localization error decreases by 69.87% for the case of the min–max method, and it decreases by 72.74% for the case of the trilateration method (the best case). Compared with the case of employing the moving average filter as the commonly used filter, the localization error only decreases by 18.67% and 12.99%, respectively.

A Comparative Study of RSSI-Based Localization Methods: RSSI Variation Caused by Human Presence and Movement

In a received signal strength indicator (RSSI) based localization system, the presence or movement of humans is one of the major effects causing RSSI variation. Using RSSI data during such a situation to estimate the target position can give large errors. Regarding this problem, in this paper, a comparison of several RSSI-based localization methods with and without human presence and movement were investigated experimentally. The major contribution of this work is that the well-known and widely used RSSI-based localization methods presented in the literature, including the min–max, the trilateration, the weighted centroid localization (WCL), and the relative span exponential weighted localization (REWL) methods, were tested. Thus, how human presence or absence influences the accuracy of these methods, and which methods show the best estimates while tolerating human movement effects can be investigated. The experiments were carried out in a laboratory and in a parking building. The results demonstrate that, without human movement effects, all methods perform very similarly. In contrast, human movements significantly increased estimation errors.Here, the maximum distance errors of the min–max, the trilateration, the WCL, and the REWL are 1.34 m, 4.09 m, 1.25 m, and 1.24 m, respectively. Obviously, the min–max, the WCL (with an optimal parameter), and the REWL (with the optimal parameter) can well tolerate the RSSI variations caused by human movements and provide significantly better accuracy than the trilateration method. Based on these findings, all the mentioned localization methods should be further improved to deal with the human movement problem.

First, second and potential third generation spreads of the COVID-19 epidemic in mainland China: an early exploratory study incorporating location-based service data of mobile devices

ObjectivesThe outbreak of atypical pneumonia caused by the novel coronavirus (COVID-19) has currently become a global concern. The generations of the epidemic spread are not well known, yet these are critical parameters to facilitate an understanding of the epidemic. A seafood wholesale market and Wuhan city, China, were recognized as the primary and secondary epidemic sources. Human movements nationwide from the two epidemic sources revealed the characteristics of the first-generation and second-generation spreads of the COVID-19 epidemic, as well as the potential third-generation spread. MethodsWe used spatiotemporal data of COVID-19 cases in mainland China and two categories of location-based service (LBS) data of mobile devices from the primary and secondary epidemic sources to calculate Pearson correlation coefficient,r, and spatial stratified heterogeneity, q, statistics. ResultsTwo categories of device trajectories had generally significant correlations and determinant powers of the epidemic spread. Bothr and q statistics decreased with distance from the epidemic sources and their associations changed with time. At the beginning of the epidemic, the mixed first-generation and second-generation spreads appeared in most cities with confirmed cases. They strongly interacted to enhance the epidemic in Hubei province and the trend was also significant in the provinces adjacent to Hubei. The third-generation spread started in Wuhan from January 17–20, 2020, and in Hubei from January 23–24. No obvious third-generation spread was detected outside Hubei. ConclusionsThe findings provide important foundations to quantify the effect of human movement on epidemic spread and inform ongoing control strategies. The spatiotemporal association between the epidemic spread and human movements from the primary and secondary epidemic sources indicates a transfer from second to third generations of the infection. Urgent control measures include preventing the potential third-generation spread in mainland China, eliminating it in Hubei, and reducing the interaction influence of first-generation and second-generation spreads.

An experimental study of the influence of a moving person on airflow characteristics and thermal conditions with diffuse ceiling ventilation

The influence of occupants'’ movements should be considered when analysing local thermal comfort. This study presents the effect of human movement on airflow characteristics and local thermal conditions with diffuse ceiling ventilation by experimental studies. A simulated person moving was used to study the human movement in an office. In these experiments, three moving speeds were studied: 0.3, 0.6 and 1.0 m/s. The simulated person moved in four cycle patterns: continuous moving and with 5 s, 10 s and 15 s interval breaks between each turn. Three heat gain levels of 40, 60 and 80 W/m2were evaluated in the chamber. The results indicate that the human movement decreased vertical temperature gradient compared with the steady-state condition. Instead, the moving intervals would have no effect on the vertical air temperature gradient. The power spectral density was increased by 90% due to the person movement compared with the steady-state condition. The moving person would create different micro-environments close to work stations than close to the moving area.

Human movement effects on the performance of the RSSI-based trilateration method: adaptive filters for distance compensation

In this paper, an experimental study of human movement effects in indoor wireless networks on the performance of the received signal strength indicator (RSSI)-based trilateration method is presented. The contribution of this work is that how the RSSI fluctuation caused by human movements nearby a target node influences the estimation accuracy of the trilateration method is studied. Additionally, efficient adaptive filters which can observe RSSI variation levels and select appropriate inputs (i.e., distance values converted from RSSI values) are proposed for handling the RSSI variation problem and compensating the position estimation error. Experiments using low-cost 2.4-GHz wireless nodes have been set and tested in a laboratory room. Results demonstrate that, during the human blocking the communication link between the transmitter and the receiver, RSSI data are fluctuated and the trilateration method shows a large estimation error. Here, the localization accuracy significantly depends on the RSSI variation level. The experimental results also indicate that, by applying our proposed solutions, they can automatically provide appropriate inputs for the trilateration method. The estimation error decreases by 43.76% and 46.28% for our test scenarios.

Human movements: immigrants and asylum seekers. Two sides of the same coin

AbstractAim: Millions of people are displaced globally, as refugees, asylum seekers or migrants. Although, at a first glance, crisis and conflicts are considered the main trigger for these movements, the migration challenge may have different roots: demographic trends, poverty, the globalization of communication, etc. The present article is an introduction to the main concepts and terminology regarding migration and it links the migration with actual labor problems within the EU.Design: The article shows how migration terminology is reflected in the EU migration policy and how migration policy affects labor policy and vice versa. The article is to be considered a state of the art or methanalysis and explains the concepts: in-migration, out-migration, refugees, asylum-seekers. In addition, it draws attention to controversies regarding the use of concepts: illegal migration, irregular migration and return migration.Conclusions: The article presents eight main economic theories of migration. Five of them have as subject of analysis the determinants of migration and the other three have the subject of analysis the perpetuation of migration. Some of the main theories analyzed here are the neoclassical theory of migration, the human capital theory of migration, the new economics theory of migration, world system theory, network theory, migration systems theory.Originality: The article demonstrates the fact that neither of these economic theories/models explain adequately the actual determinants of migration and it proposes a new model focused more on the transdisciplinary effects of human movements. Keywords: migration, crisis, development, asylum seekers, labor market policiesJEL: J015, J61, J15

Implementation and test of an RSSI-based indoor target localization system: Human movement effects on the accuracy

The movement of humans in wireless networks is one of major effects leading to significant received signal strength indicator (RSSI) variation. Using fluctuated RSSI on estimating the target position in the RSSI-based indoor localization system can give large error and poor decision of the system. In this paper, how the human movement affects the accuracy of an implemented indoor target localization system is explored by experiments, and a proposed simple RSSI filtering solution as the guideline solution to directly handle such a research problem is also presented. For our purpose, firstly, the RSSI-based indoor target localization system, which consists of design communication operations for measuring the RSSI in the wireless network and selected well-known localization methods (i.e. the min-max and the trilateration methods) for estimating the target position, is implemented and tested. Secondly, selected well-known filtering methods (i.e. the moving average and the exponentially weighted moving average filters) and the span thresholding filter (i.e. the proposed solution) are applied for reducing the RSSI variation and the estimated position error caused by the human movement. Our experiments have been carried out in an indoor environment. An LPC2103F microcontroller interfacing with a 2.4 GHz CC2500 RF module is developed and employed as the wireless node. Experimental results reveal that the estimated position error determined by the min-max and the trilateration methods significantly increases during the human movement, and converts according to human movement patterns and numbers of movement people. Also, the results demonstrate that by applying the moving average filter with a high window size and the exponentially weighted moving average filter with an optimal weighting factor to raw RSSI data, the estimated position error is not much improved. In contrast, the span thresholding filter gives better results and can directly cope with the human movement problem. In average, the localization error and the standard deviation decrease 11.921% and 42.086% in the case of the min-max method, and they decrease 44.535% and 87.154% in the case of the trilateration method.

Stability analysis of a fractional order model for the HIV/AIDS epidemic in a patchy environment

A multi-patch HIV/AIDS epidemic model with fractional order derivative is formulated to investigate the effect of human movement on the spread of HIV/AIDS epidemic among patches. We derive the basic reproduction number R 0 and prove that if R 0 < 1 , the disease-free equilibrium (DFE) is locally and globally asymptotically stable. In the case of R 0 > 1 , we obtain sufficient conditions under which the endemic equilibrium is unique and globally asymptotically stable. We also formulate a fractional optimal control problem (FOCP), in which the state and co-state equations are given in terms of the left fractional derivatives. We incorporate into the model time dependent controls aimed at controlling the spread of HIV/AIDS epidemic. The necessary conditions for fractional optimal control of the disease are obtained. The simulation of the model is done with two patches. The numerical results show that implementing all the control efforts decreases significantly the number of HIV-infected and AIDS people in both patches. In addition, the value of R c , the control reproduction number, for a long time is at its minimum level, and the value of objective functional J(u) increases when the fractional derivative order α is reduced from 1 ( 0 . 8 ≤ α ≤ 1 ).

Population Movement as a Risk Factor for Malaria Infection in High-Altitude Villages of Tahtay-Maychew District, Tigray, Northern Ethiopia: A Case-Control Study.

Key goal and targets of the Ethiopia National Malaria Control Program are to achieve malaria elimination within specific geographical areas with historically low malaria transmission and to reach near-zero malaria transmission in the remaining malarious areas by 2020. However, back and forth population movement between high-transmission and low-transmission area imposes challenge on the success of national malaria control programs. Therefore, examining the effect of human movement and identification of at-risk populations is crucial in an elimination setting. A matched case-control study was conducted among 520 study participants at a community level in low malaria transmission settings in northern Ethiopia. Study participants who received a malaria test were interviewed regarding their recent travel history. Bivariate and multivariate analyses were carried out to determine if the reported travel was related to malaria infection. Younger age (adjusted odds ratio [AOR] = 3.20, 95% confidence interval [CI]: 1.73, 5.89) and travel in the previous month (AOR = 11.40, 95% CI: 6.91, 18.82) were statistically significant risk factors for malaria infection. Other statistically significant factors, including lower educational level (AOR = 2.21, 95% CI: 1.26, 3.86) and nonagricultural in occupation (AOR = 2.0, 95% CI: 1.02, 3.94), were also found as risk factors for malaria infection. Generally, travel history was found to be a strong predictor for malaria acquisition in the high-altitude villages. Therefore, besides the existing efforts in endemic areas, targeting those who frequently travel to malarious areas is crucial to reduce malaria infection risks and possibility of local transmissions in high-altitude areas of northern Ethiopia.

Assessment of optimal strategies in a two-patch dengue transmission model with seasonality.

Emerging and re-emerging dengue fever has posed serious problems to public health officials in many tropical and subtropical countries. Continuous traveling in seasonally varying areas makes it more difficult to control the spread of dengue fever. In this work, we consider a two-patch dengue model that can capture the movement of host individuals between and within patches using a residence-time matrix. A previous two-patch dengue model without seasonality is extended by adding host demographics and seasonal forcing in the transmission rates. We investigate the effects of human movement and seasonality on the two-patch dengue transmission dynamics. Motivated by the recent Peruvian dengue data in jungle/rural areas and coast/urban areas, our model mimics the seasonal patterns of dengue outbreaks in two patches. The roles of seasonality and residence-time configurations are highlighted in terms of the seasonal reproduction number and cumulative incidence. Moreover, optimal control theory is employed to identify and evaluate patch-specific control measures aimed at reducing dengue prevalence in the presence of seasonality. Our findings demonstrate that optimal patch-specific control strategies are sensitive to seasonality and residence-time scenarios. Targeting only the jungle (or endemic) is as effective as controlling both patches under weak coupling or symmetric mobility. However, focusing on intervention for the city (or high density areas) turns out to be optimal when two patches are strongly coupled with asymmetric mobility.

The Impact of Evolutionary Driving Forces on Human Complex Diseases: A Population Genetics Approach.

Investigating the molecular evolution of human genome has paved the way to understand genetic adaptation of humans to the environmental changes and corresponding complex diseases. In this review, we discussed the historical origin of genetic diversity among human populations, the evolutionary driving forces that can affect genetic diversity among populations, and the effects of human movement into new environments and gene flow on population genetic diversity. Furthermore, we presented the role of natural selection on genetic diversity and complex diseases. Then we reviewed the disadvantageous consequences of historical selection events in modern time and their relation to the development of complex diseases. In addition, we discussed the effect of consanguinity on the incidence of complex diseases in human populations. Finally, we presented the latest information about the role of ancient genes acquired from interbreeding with ancient hominids in the development of complex diseases.