Journal articles on the topic 'Non-saturated traffic'
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Bacco, Manlio, Pietro Cassara, Marco Colucci, and Alberto Gotta. "Modeling Reliable M2M/IoT Traffic Over Random Access Satellite Links in Non-Saturated Conditions." IEEE Journal on Selected Areas in Communications 36, no. 5 (May 2018): 1042–51. http://dx.doi.org/10.1109/jsac.2018.2832799.
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Li, Jun, Yifeng Zhou, Louise Lamont, Mylène Toulgoat, and Camille A. Rabbath. "Packet Delay in UAV Wireless Networks Under Non-saturated Traffic and Channel Fading Conditions." Wireless Personal Communications 72, no. 2 (February 26, 2013): 1105–23. http://dx.doi.org/10.1007/s11277-013-1057-4.
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Sarkar, Subhadeep, Sudip Misra, Bitan Bandyopadhyay, Chandan Chakraborty, and Mahammad S. Obaidat. "Performance Analysis of IEEE 802.15.6 MAC Protocol under Non-Ideal Channel Conditions and Saturated Traffic Regime." IEEE Transactions on Computers 64, no. 10 (October 1, 2015): 2912–25. http://dx.doi.org/10.1109/tc.2015.2389806.
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Hadiuzzaman, M., and M. Mizanur Rahman. "Capacity Analysis for Fixed-Time Signalized Intersection for Non-Lane Based Traffic Condition." Advanced Materials Research 83-86 (December 2009): 904–13. http://dx.doi.org/10.4028/www.scientific.net/amr.83-86.904.
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Capacity analysis of signalized intersections basically consists of estimating saturation flow and delay. Pre-timed signals are most commonly used in developing countries. This research deals with development of saturation flow and delay models for pre-timed signalized intersections with reference to non-lane based traffic condition prevailing in Bangladesh. In order to account non-uniformity in the static and dynamic characteristics of the vehicles passenger car unit (PCU) values for each vehicle is found out using synchronous regression technique and a range of site-specific PCU values were obtained. From this study, it has been observed that unified PCU concept does not hold good for non-lane based traffic condition and it has been recommended that the analysis should be site specific for non-lane based traffic condition. The saturation flow for each study approach was calculated using the average PCU values and multiple linear regression techniques were then used to derive predictive saturation flow models. Field delay for each approach is calculated based on HCM 2000 guidelines. It has been observed that HCM 2000 delay model consistently over estimate delay at degree of saturation more than 1.0. It has been suggested from the analysis that theoretical incremental delay (due to random arrival and over saturated queues) in HCM 2000 delay model be reduced by 70 % to better reflect field conditions in capacity analysis for non lane based traffic condition.
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Lee, Gyu-min, Byeong-hee Roh, Jimyeong Oh, Sungjin Kang, and Do-kyung Kim. "Estimation of the Number of Contending Secondary Users in Distributed Cognitive Radio Environment with Non-Saturated Traffic Patterns." Journal of Korean Institute of Communications and Information Sciences 44, no. 3 (March 31, 2019): 490–97. http://dx.doi.org/10.7840/kics.2019.44.3.490.
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Nguyen, VanDung, Tran Anh Khoa, Thant Zin Oo, Nguyen H. Tran, Choong Seon Hong, and Eui-Nam Huh. "Time Slot Utilization for Efficient Multi-Channel MAC Protocol in VANETs." Sensors 18, no. 9 (September 10, 2018): 3028. http://dx.doi.org/10.3390/s18093028.
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In vehicular ad hoc networks (VANETs), many schemes for a multi-channel media access control (MAC) protocol have been proposed to adapt to dynamically changing vehicle traffic conditions and deliver both safety and non-safety packets. One such scheme is to employ both time-division multiple access (TDMA) and carrier-sense multiple access (CSMA) schemes (called a hybrid TDMA/CSMA scheme) in the control channel (CCH) interval. The scheme can adjust the length of the TDMA period depending on traffic conditions. In this paper, we propose a modified packet transmitted in the TDMA period to reduce transmission overhead under a hybrid TDMA/CSMA multi-channel MAC protocol. Simulation results show that a MAC protocol with a modified packet supports an efficient packet delivery ratio of control packets in the CCH. In addition, we analyze the hybrid TDMA/CSMA multi-channel MAC protocol with the modified packet under saturated throughput conditions on the service channels (SCHs). The analysis results show that the number of neighbors has little effect on the establishment of the number of time slots in TDMA periods and on SCHs under saturated throughput conditions.
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Tsakyridis, Apostolos, Miltiadis Moralis-Pegios, Christos Vagionas, Eugenio Ruggeri, George Kalfas, Amalia Miliou, and Nikos Pleros. "A Deeply Saturated Differentially-Biased SOA-MZI for 20 Gb/s Burst-Mode NRZ Traffic." Applied Sciences 9, no. 15 (July 25, 2019): 2971. http://dx.doi.org/10.3390/app9152971.
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We experimentally demonstrate an optical Burst-Mode Wavelength Converter (BMWC) that simultaneously provides power equalization and wavelength conversion of Non-Return to Zero-On/Off Keying (NRZ-OOK) data and operates up to 20 Gb/s. It employs a balanced, differentially-biased, Semiconductor Optical Amplifier-Mach Zehnder Interferometer (SOA-MZI) operating in deeply saturated regime and its performance is evaluated at 10 Gb/s and 20 Gb/s with loud/soft peak–power ratios up to 9 dB and 5 dB, respectively. Bit Error Rate (BER) measurements reveal error free operation with up to 6.1 dB BER improvement at 10 Gb/s and 3.51 dB at 20 Gb/s, while the use of a single SOA-MZI yields 50% reduction in the number of active components against state-of-the-art BMWCs. Finally, the proposed BMWC is evaluated in non-dispersion compensated 25 km fiber transmission experiment, providing error-free operation with 1.43 dB BER improvement, validating its capabilities for potential employment in Passive Optical Networks (PON) and 5G fronthaul networks.
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Setyowati, Rustiana, and Siti Maria Ulfa. "Hubungan Beban Kerja Dan Lingkungan Kerja Terhadap Stres Kerja Pada Polisi Satlantas Polres Bantul." Jurnal Manajemen Kesehatan Yayasan RS.Dr. Soetomo 6, no. 2 (November 10, 2020): 169. http://dx.doi.org/10.29241/jmk.v6i2.338.
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In Indonesia cases of stress due to workload in the work environment of the police have occurred in several areas and have had quite serious impacts. The Research was conducted at the traffic police Special Region of Yogyakarta in 2019. This Research is a quantitative non experimental research with correlational descriptive. Data analysis techniques using multiple linier regression analysis. Respondents as many as 50 police Bantul Police Traffic Unit, the sample uses a saturated sample.The Study aims to determine the relationship of workload and work environment to work stress of Bantul Police Traffic Unit. The results of the study stated that the traffic police unit that has a light workload of 3 people (6%) moderate 39 people (78%) and weighs 8 people(16%) while the traffic unit police who have a light work environment are 6 people (12%) moderate work environment as many as 31 people (62%) and high work environment as many as 13 people (26%). While the traffic police who have low work stress are 6 people (12%) moderate are 34 people (68%) and heavy are 10 people (20%). Data Analysis using multiple linier regression with a coefficient of deternination. 1,907 and F calculated 49,41 and F table 3,23. The results of the study concluded that there was a relationship between workload and worke nvironment on the work stress of the traffic police at Bantul Region Police Station in Yogyakarta Keywords : Load, environment, Stress, Traffic Police unit
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Lee, Kyu-haeng. "Performance Analysis of the IEEE 802.11ax MAC Protocol for Heterogeneous Wi-Fi Networks in Non-Saturated Conditions." Sensors 19, no. 7 (March 29, 2019): 1540. http://dx.doi.org/10.3390/s19071540.
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The IEEE 802.11ax standard, which realizes multi-user transmission based on orthogonal frequency division multiple access (OFDMA), has been highlighted as a key technology to meet high future demand for Wi-Fi systems. Since this standard is still being developed, performance analysis through mathematical modeling is of paramount importance; however, existing studies have several limitations. Firstly, most of these consider only the saturation network throughput, whereas for 802.11ax in particular, the access delay of the nodes needs to be studied carefully, since they no longer acquire the medium independently but depend solely on the access point’s (AP’s) schedule. Secondly, since the network performance may be affected to a greater extent by legacy nodes than by 802.11ax nodes, it is desirable to consider various heterogeneous cases of networks with existing legacy nodes. In this paper, a new analytical framework for the 802.11ax MAC protocol is provided. Markov-chain-based models are developed to represent the behavior of the 802.11ax nodes, and both non-saturated traffic conditions and co-existence with the legacy nodes are considered. Through both analysis and MATLAB simulations, it is shown that the proposed model accurately evaluates the throughput and the delay performance under various network conditions.
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Grigoropoulos, Georgios, Seyed Abdollah Hosseini, Andreas Keler, Heather Kaths, Matthias Spangler, Fritz Busch, and Klaus Bogenberger. "Traffic Simulation Analysis of Bicycle Highways in Urban Areas." Sustainability 13, no. 3 (January 20, 2021): 1016. http://dx.doi.org/10.3390/su13031016.
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The ongoing increase of bicycle traffic in urban areas forces transport authorities to reconsider the space allocation for different transport modes. Transport policies favor the introduction of high-quality bicycle infrastructure along urban corridors to improve the traffic quality and safety for bicyclists but more importantly to increase the attractiveness of bicycling and over vehicular modes. Especially in urban areas with an already established high and steadily increasing share of bicyclists, the introduction of bicycle highways is considered to further alleviate saturated interurban public transport and motor vehicle connections and increase the average traveled distance by non-motorized modes. Due to the expensive implementation costs and the space restrictions in already built-up urban environments, there should be an extensive planning phase for defining the expected changes in traffic efficiency and safety. However, the effects of urban bicycle highways on traffic performance metrics of bicyclists as well as other road users are not thoroughly studied. This paper aims to quantify and assess the potential effects of urban bicycle highway on road users. The study considers a possible inner-city pilot route in the city of Munich, where the present bicycle infrastructure is planned to be upgraded to a bicycle highway. A simulation model is designed using traffic data from field observations and future estimates for the traffic composition. Through microscopic traffic simulation, the potential effects of the introduced infrastructure on road users are determined for different study scenarios. Results show that traffic quality thresholds for bicycle highways, as defined in official guidelines, can only be fulfilled through the implementation of special bicycle traffic control measures such as bicycle coordination or bicycle passage time extension. Finally, unidirectional bicycle highways together with bicycle passage time extension provided the best overall traffic performance for bicycle traffic and motor vehicle traffic.
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Babio, Nancy, Paloma Vicent, Leonor López, Anna Benito, Julio Basulto, and Jordi Salas-Salvadó. "Adolescents’ ability to select healthy food using two different front-of-pack food labels: a cross-over study." Public Health Nutrition 17, no. 6 (May 17, 2013): 1403–9. http://dx.doi.org/10.1017/s1368980013001274.
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AbstractObjectiveTo compare, in adolescents, two models of front-of-pack Guideline Daily Amounts (GDA) labels in terms of (i) friendliness and acceptance and (ii) the ability to choose a diet that closely follows the nutritional recommendations.DesignA randomized cross-over study was designed to compare two simplified front-of-pack GDA nutrition labels.SettingA Spanish secondary school.SubjectsEighty-one healthy adolescents aged between 14 and 16 years were recruited. Participants were randomly exposed to two experimental non-real food-choice conditions using multiple-traffic-light or monochrome nutritional labels. Participants had to choose options from a closed menu for 5 d on the basis of the experimental front-of-pack labelling. For each meal, three food options with different nutritional compositions were given to the participants. The contents of total energy and fat, saturated fat, sugar and salt of the chosen options were calculated.ResultsThere were no significant differences in baseline sociodemographic and anthropometric characteristics between participants regardless of the experimental condition in which they started. There were no carry-over effects between the experimental sequences. It was observed that when participants used the multiple-traffic-light GDA system they chose significantly less total energy (mean –123·1 (sd 211·0) kJ (−29·4 (sd 50·4) kcal), P < 0·001), sugar (−4·5 (sd 4·6) g, P < 0·001), fat (−2·1 (sd 4·5) g, P = 0·006), saturated fat (−1·0 (sd 1·9) g, P = 0·002) and salt (−0·4 (sd 0·5) g, P < 0·001) than when they used the monochrome GDA system.ConclusionsCompared with the monochrome GDA front-of-pack nutritional label, the multiple-traffic-light system helped adolescents to differentiate between healthier and less healthy food, theoretically making it possible for them to choose a diet closer to dietary recommendations.
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Jia, Peng Fei, and Ai Wu Yang. "A Modified Davidenkov Model for Stiffness and Damping Characteristics of Saturated Clayey Soils due to Low-Amplitude Small-Strain Vibrations." Advanced Materials Research 680 (April 2013): 166–71. http://dx.doi.org/10.4028/www.scientific.net/amr.680.166.
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Railway track and nearby structures in the vicinity of high-speed railway are exposed to low-amplitude small-strain vibrations as high-speed railway traffic construction activities arise. These low-level dynamic events can lead to a non-linear softening behavior of the “elastic” stiffness and a considerable amount of energy dissipation in soils with a gradually increasing strain. The modelling of these non-linear behaviours are an important to predict lifetime and serviceability of existing structures in the vicinity of high-speed railway. An objective of this study is to develop validated computational models that can be used to perform stiffness and damping characteristics of saturated clayey soils due to low-amplitude small-strain vibrations. This paper provides an insight in the normalized shear modulus G/Gmax and damping ratio D in relation with shear strain amplitude γ through free-vibration column test, and proposes a modified Davidenkov model.
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Wiles, Charles E., Ameen I. Ramzy, and Howard Belzberg. "Cellular Telecommunications at Amtrak's Worst Crash." Prehospital and Disaster Medicine 4, no. 2 (December 1989): 160–62. http://dx.doi.org/10.1017/s1049023x00029952.
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AbstractMedical communications associated with a collision between a passenger train and three locomotives which resulted in the death of 16 and injury to at least 177 persons quickly overwhelmed the relatively sophisticated EMS communications center (SYSCOM) serving the state of Maryland, U.S.A. Other than traditional talk-by and ambulance-hospital communications, the system was saturated by: 1) communications between seven prehospital sectors; 2) persons moved into the field from their usual in-hospital environment who were not familiar or experienced with the use of radio communications; 3) traffic generated through the operations of 11 helicopters; and 4) the usual confusion that accompanies such events. The use of cellular telephones during this incident, substantially enhanced all levels of communications. Many of the participants expressed preference for this form of communications compared to the use of radios.Problems associated with the use of cellular telephone communications included an insufficient number of channels made available by the telephonecommunications provider causing competition with non-essential personnel for use, and relatively short battery life. These problems can be solved by the provider opening more channels and by the use of larger power sources such as automobile storage batteries. It is concluded that portable and vehicle-mounted cellular telephones can serve as useful communications tools in mass casualty and disaster situations.
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Céspedes, Máximo Morales, Borja Genovés Guzmán, and Víctor P. Gil Jiménez. "Lights and Shadows: A Comprehensive Survey on Cooperative and Precoding Schemes to Overcome LOS Blockage and Interference in Indoor VLC." Sensors 21, no. 3 (January 28, 2021): 861. http://dx.doi.org/10.3390/s21030861.
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Visible light communications (VLC) have received significant attention as a way of moving part of the saturated indoor wireless traffic to the wide and unregulated visible optical spectrum. Nowadays, VLC are considered as a suitable technology, for several applications such as high-rate data transmission, supporting internet of things communications or positioning. The signal processing originally derived from radio-frequency (RF) systems such as cooperative or precoding schemes can be applied to VLC. However, its implementation is not straightforward. Furthermore, unlike RF transmission, VLC present a predominant line-of-sight link, although a weak non-LoS component may appear due to the reflection of the light on walls, floor, ceiling and nearby objects. Blocking effects may compromise the performance of the aforementioned transmission schemes. There exist several surveys in the literature focused on VLC and its applications, but the management of the shadowing and interference in VLC requires a comprehensive study. To fill this gap, this work introduces the implementation of cooperative and precoding schemes to VLC, while remarking their benefits and drawbacks for overcoming the shadowing effects. After that, the combination of both cooperative and precoding schemes is analyzed as a way of providing resilient VLC networks. Finally, we propose several open issues that the cooperative and precoding schemes must face in order to provide satisfactory VLC performance in indoor scenarios.
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Marvi, Murk, Adnan Aijaz, and Muhammad Khurram. "Toward a Unified Framework for Analysis of Multi-RAT Heterogeneous Wireless Networks." Wireless Communications and Mobile Computing 2019 (January 3, 2019): 1–19. http://dx.doi.org/10.1155/2019/6918637.
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The increased penetration of different radio access technologies (RATs) and the growing trend towards their convergence necessitates the investigation of wireless heterogeneous networks (HetNets) from coverage and capacity perspective. This paper develops a unified framework for signal-to-interference-plus-noise ratio and rate coverage analysis of multi-RAT HetNets, with each RAT employing either a contention-free or a contention-based channel access strategy. The proposed framework adopts tools from stochastic geometry, with the location of APs and mobile users modeled through independent Poisson point processes (PPPs). We specifically focus on a two-RAT scenario (i.e., cellular and Wi-Fi), where for multi-tier Wi-Fi RAT, with contention-based channel access like CSMA/CA, the location dependent distribution of interfering APs has been approximated through a homogeneous PPP. Moreover, by using some simple yet realistic set of assumptions, the distance to nearest active AP has been defined which results in simplified expressions. The medium access probability for a random and a tagged AP under a multi-tier Wi-Fi RAT has also been derived and discussed. By keeping in view the tremendous effect of temporal domain on overall network performance, the stable queue probability has been derived by assuming a non-saturated traffic model. The results have been validated through extensive simulations and compared with existing approaches. Some useful insights have also been presented that shed light on design and analysis of multi-RAT HetNets and provide motivation for further research in this direction.
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Nordström, T., T. Mustelin, T. Pessa-Morikawa, and L. C. Andersson. "Modulation of calcium fluxes in Jurkat T cells by myristic acid. Inhibition is independent of membrane potential and intracellular pH." Biochemical Journal 283, no. 1 (April 1, 1992): 113–18. http://dx.doi.org/10.1042/bj2830113.
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Treatment of T lymphocytes with mitogenic antibodies against the T-cell receptor/CD3 complex induces within seconds a rise in the concentration of intracellular free Ca2+. We recently reported that free myristic acid, but not its methyl ester, inhibits both the anti-CD3-induced Ca2+ influx across the cell membrane and the Ca2+ release from intracellular stores in Jurkat T cells. Here we show that myristic acid induced a rapid hyperpolarization of the cell membrane potential and a decrease in intracellular pH in Jurkat cells. Lauric acid and palmitic acid caused minor hyperpolarization, whereas other saturated non-esterified fatty acids tested were without effect. Hyperpolarization of the membrane potential in Jurkat cells with valinomycin did not, however, inhibit the anti-CD3-induced Ca2+ signal, and the blocking effect on the Ca2+ signal in myristic acid-treated Jurkat cells was not reversed after normalization of the cell membrane potential by treatment with gramicidin. The inhibitory effect of myristic acid on the Ca2+ fluxes thus cannot be explained by changes in membrane potential. We also present evidence that the blocking effect of myristic acid on the receptor-operated Ca2+ flux is not due to the myristic acid-induced decrease in intracellular pH. Moreover, we demonstrate that myristic acid does not prevent the release of Ca2+ triggered by inositol 1,4,5-trisphosphate from intracellular pools in permeabilized cells. Our findings indicate that myristic acid blocks anti-CD3-induced Ca2+ traffic in Jurkat cells by interfering with the regulation of Ca2+ mobilization, apparently by blocking an early step in signal transduction from the T-cell-antigen receptor/CD3 complex.
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Chalbot, M. C. G., J. Brown, P. Chitranshi, G. Gamboa da Costa, E. D. Pollock, and I. G. Kavouras. "Functional characterization of the water-soluble organic carbon of size fractionated aerosol in the Southern Mississippi Valley." Atmospheric Chemistry and Physics Discussions 14, no. 3 (February 10, 2014): 3629–66. http://dx.doi.org/10.5194/acpd-14-3629-2014.
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Abstract. The chemical content of the water soluble organic carbon (WSOC) as a function of particle size was characterized in Little Rock, Arkansas in winter and spring 2013. The objectives of this study were to: (i) compare the functional characteristics of coarse, fine and ultrafine WSOC and (ii) reconcile the sources of WSOC for the period when carbonaceous aerosol was the most abundant particulate component. The WSOC accounted for 5% of particle mass for particles with dp > 0.96 μm and 10% of particle mass for particles with dp < 0.96 μm. Non-exchangeable aliphatic (H-C), unsaturated aliphatic (H-C-C=), oxygenated saturated aliphatic (H-C-O), acetalic (O-CH-O) and aromatic (Ar-H) protons were determined by proton nuclear magnetic resonance. The total non-exchangeable organic hydrogen concentrations varied from 4.1 ± 0.1 nmol m−3 for particles with 0.96 < dp < 1.5 μm to 73.9 ± 12.3 nmol m−3 for particles with dp < 0.49 μm, resulting in molar H / C ratios of 0.48 ± 0.05 to 0.92 ± 0.09 observed in combustion-related organic aerosol. The R-H was the most abundant group representing about 45% of measured total non-exchangeable organic hydrogen concentration followed by H-C-O (27%) and H-C-C= (26%). Levoglucosan, amines, ammonium and methanosulfonate were tentatively identified in NMR fingerprints of fine particles. Sucrose, fructose, glucose, formate and acetate were associated with coarse particles. These qualitative differences of 1H-NMR profiles for different particle sizes indicated the possible contribution of biological aerosol and a mixture of aliphatic and oxygenated compounds from biomass burning and traffic exhausts. The concurrent presence of ammonium and amines also suggested the presence of ammonium/aminium nitrate and sulfate secondary aerosol. The size-dependent origin of WSOC was further corroborated by the increasing δ13C abundance from −26.81 ± 0.18‰ for the smallest particles to −25.93 ± 0.31‰ for the largest particles and the relative distribution of the functional groups as compared to those previously observed for marine, biomass burning and secondary organic aerosol. The latter also allowed for the differentiation of urban combustion-related aerosol and biological particles. The five types of organic hydrogen accounted for the majority of WSOC for particles with dp > 3.0 μm and dp < 0.96 μm.
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Chalbot, M. C. G., J. Brown, P. Chitranshi, G. Gamboa da Costa, E. D. Pollock, and I. G. Kavouras. "Functional characterization of the water-soluble organic carbon of size-fractionated aerosol in the southern Mississippi Valley." Atmospheric Chemistry and Physics 14, no. 12 (June 20, 2014): 6075–88. http://dx.doi.org/10.5194/acp-14-6075-2014.
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Abstract. The chemical content of water-soluble organic carbon (WSOC) as a function of particle size was characterized in Little Rock, Arkansas in winter and spring 2013. The objectives of this study were to (i) compare the functional characteristics of coarse, fine and ultrafine WSOC and (ii) reconcile the sources of WSOC for periods when carbonaceous aerosol was the most abundant particulate component. The WSOC accounted for 5% of particle mass for particles with dp > 0.96 μm and 10% of particle mass for particles with dp < 0.96 μm. Non-exchangeable aliphatic (H–C), unsaturated aliphatic (H–C–C=), oxygenated saturated aliphatic (H–C–O), acetalic (O–CH–O) and aromatic (Ar–H) protons were determined by proton nuclear magnetic resonance (1H-NMR). The total non-exchangeable organic hydrogen concentrations varied from 4.1 ± 0.1 nmol m−3 for particles with 1.5 < dp < 3.0 μm to 73.9 ± 12.3 nmol m−3 for particles with dp < 0.49 μm. The molar H / C ratios varied from 0.48 ± 0.05 to 0.92 ± 0.09, which were comparable to those observed for combustion-related organic aerosol. The R–H was the most abundant group, representing about 45% of measured total non-exchangeable organic hydrogen concentrations, followed by H–C–O (27%) and H–C–C= (26%). Levoglucosan, amines, ammonium and methanesulfonate were identified in NMR fingerprints of fine particles. Sucrose, fructose, glucose, formate and acetate were associated with coarse particles. These qualitative differences of 1H-NMR profiles for different particle sizes indicated the possible contribution of biological aerosols and a mixture of aliphatic and oxygenated compounds from biomass burning and traffic exhausts. The concurrent presence of ammonium and amines also suggested the presence of ammonium/aminium nitrate and sulfate secondary aerosol. The size-dependent origin of WSOC was further corroborated by the increasing δ13C abundance from −26.81 ± 0.18‰ for the smallest particles to −25.93 ± 0.31‰ for the largest particles and the relative distribution of the functional groups as compared to those previously observed for marine, biomass burning and secondary organic aerosol. The latter also allowed for the differentiation of urban combustion-related aerosol and biological particles. The five types of organic hydrogen accounted for the majority of WSOC for particles with dp > 3.0 μm and dp < 0.96 μm.
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Little, David I., and Bernard Fichaut. "VISUAL COMPARISONS OF SELECTED SHORES AFFECTED BY THE Prestige OIL SPILL, NORTHERN SPAIN 2002–2004." International Oil Spill Conference Proceedings 2005, no. 1 (May 1, 2005): 685–88. http://dx.doi.org/10.7901/2169-3358-2005-1-685.
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ABSTRACT Walkover and photographic surveys were conducted on four occasions up to February 2004 on shorelines of Galicia, Asturias and Vizcaya that were severely affected by Heavy Fuel Oil (HFO) from the November 2002 Prestige incident. The geomorphology and ecology impacts resulting from both the oil and cleanup actions were observed by experienced scientists. Some cleanup methods worked well, and environmental disturbance was minimized. However, inefficient or over-zealous treatments also occurred, particularly early in the incident response. The study showed that rocky headlands are now often clean, and that wave-cut rock platforms have been cleaned effectively by high-pressure flushing. Maritime vegetation has, however, been trampled and oiled secondarily in the supra-tidal zone. Backshore botanical impacts resulted from cleanup equipment lay-down, vehicle refueling, and vehicular and pedestrian traffic. In some cases, vegetation and often soil removal during construction of access routes across the backshore will mean permanent adverse impact. Boulder and cobble storm berms were often oil-saturated above the mean high water level. Some of these are in fact relict geomorphic features inherited from previous higher sea levels during the interglacial periods, and so natural recovery would be very slow indeed. These coarse deposits were commonly treated by inefficient storm berm relocation, although good results were also achieved elsewhere. Numerous cases were seen of underlying and non-oiled finer sediments being exposed to erosion. Vegetation and substrate impacts were most severe where oil quantities were large and cleanup protracted or imperfectly supervised. Generally, estuaries were well protected by booming, and were only slightly oiled. Sand dunes have also escaped the worst impacts of oil and intrusive cleanup. There was, however, criticism of the government's handling of offers of advice from Spanish scientists expert in shoreline dynamics. This was in contrast to the international cooperation that typified the tracking, modeling and cleanup of oil offshore. It is recommended that existing best practices (e.g. Shoreline Cleanup Assessment Technique; SCAT) be more widely adopted in spills with potentially prolonged and injurious shoreline cleanups.
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Apuani, Tiziana, Marco D'Attoli, Marco Masetti, and Federico Fischanger. "Change of hydraulic conductivity of cohesive soils due to consolidation treatments with expanding resins." Acque Sotterranee - Italian Journal of Groundwater 7, no. 3 (September 25, 2018): 33–45. http://dx.doi.org/10.7343/as-2018-340.
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Settlements of ground subjected to foundation load are often due to both natural and/or anthropogenic causes, such as differential consolidation, seepage, periods of drought alternating with heavy rainfalls, growth of tree roots, sewer leaks, vibrations induced by vehicle traffic, excavations, or construction defects. Techniques of soil consolidation and stabilization by means of injection of polyurethane expanding resins have been efficiently used to mitigate or even solve this issue. The efficiency of the resin injection treatment has been well documented also thanks to the develop of a procedure of planning and monitoring which combines traditional geotechnical tests with the application of electrical resistivity tomography, which is strongly sensitive to the presence of water or voids. The combination of these survey methodologies allows to recognize the effect of injection in terms of soil compaction and water migration, a key factor for understanding the phenomenon and planning of resolutive interventions. The present study follows a previous work aimed at evaluating the increase in the geotechnical performance of cohesive soils treated by injection of expanding resins (same soil, resin, at the same site) and integrates it by focusing on the quantification of the effects of consolidation treatments, by means of expanding resins injection, on hydrologic properties of cohesive soils, focusing on saturated hydraulic conductivity measurements. Laboratory permeability test, performed in triaxial cell at different stress conditions and hydraulic gradients, were performed on undisturbed samples collected on “natural (non-treated)” and “treated soils”, before and after the injection of resin (MAXIMA ® by GEOSEC ® ) in a full-scale test site characterized by the presence of continuous and homogeneous cohesive soils, (clay and silts). The investigated soil is classified as CH or CL soil, very firm and apparently overconsolidated. The study shows how the treatment is able to modify the characteristics of hydraulic conductivity of the soil. The injected resins partly follow pre-existing weaknesses and partly impregnate homogeneous and continuous masses of soil in a capillary way, giving it, in addition to the already documented greater mechanical strength, a lower hydraulic conductivity. The electrical resistivity investigations allow to appreciate the volumes affected by the treatment to which the variations of the measured properties can be attributed.
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Prayitno, Eko, and Veronika Veronika. "KAJIAN KINERJA PERSIMPANGAN TIDAK BERSINYAL (STUDI KASUS : PERSIMPANGAN TIGA GADUT, JALAN RAYA INDARUNG – BANDAR BUAT, KOTA PADANG)." Rang Teknik Journal 2, no. 2 (April 24, 2019). http://dx.doi.org/10.31869/rtj.v2i2.1183.
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The highway is one of the infrastructure for the smooth traffic. One part of the road that are considered necessary to be analyzed and evaluated is an intersection. Three Gadut intersection is non signalized intersection. The traffic flow is quite dense, and lack of discipline of road user factors competing space to pass the crossing, resulting in congestion is very influential on traffic conditions at peak hours in the morning, afternoon and evening. Prior to conducting the survey, the first to do is survey the condition of the intersection that includes geometric characteristics and traffic volume. From the analysis of environmental data, side friction factor to the junction of three Gadut is the criteria being. Rated capacity (C) the smallest is 3706.3 smp/hour, the degree of saturation of 1.1 smp/hour. This value is over the limit permitted values manually indonesian road capacity of 0.8 to 0.9 (1.1> 0.9), it is concluded that the traffic flow is the crossroads of three Gadut saturated traffic flow. The queue probability value between 128.8% - 157.4% with a total delay largest average 11.57 seconds/smp. It is concluded that the chances of a queue at the intersection of three Gadut very large, so it could cause congestion.
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Chauhan, Ritvik, Ashish Dhamaniya, and Shriniwas Arkatkar. "Driving Behavior at Signalized Intersections Operating under Disordered Traffic Conditions." Transportation Research Record: Journal of the Transportation Research Board, August 19, 2021, 036119812110338. http://dx.doi.org/10.1177/03611981211033863.
Full textAbstract:
A higher degree of heterogeneity in vehicle class and drivers, coupled with non-lane-based driving habits, creates several challenges in traffic flow analysis. This study investigates vehicles’ microscopic driving behavior at signalized intersections operating under weak lane discipline with mixed traffic (disordered) conditions. For this purpose, a comprehensive vehicular trajectory data set is developed from field-recorded video footage using a semi-automated tool for data extraction. Microscopic parameters such as relative velocity, spacing between vehicles, following time, lane preference, longitudinal and lateral speed profile, hysteresis evidence, and lateral movement of different vehicle classes during different traffic phases are presented in the study. The data is then segregated into three flow conditions: stopped flow, saturated flow, and unaffected flow. It is found that smaller vehicles prefer near-side lanes over far-side lanes. Motorized three-wheeler (3W) and motorized two-wheeler (2W) vehicle classes exhibit the greatest lateral velocity, lateral movement, and aggressiveness. This results in several interactions between vehicles as a function of different leader–follower vehicle pairs. Signalized intersections with more heterogeneity in traffic composition, especially higher composition of 2W and 3W vehicle classes, exhibit higher levels of aggressive driving behavior that might lower safety standards. As a practical application, ranges of various driving behavior parameter values for different leader–follower combinations and traffic conditions are quantified in the study. The observations and results are expected to help better understand prevailing driving behavior in disordered traffic and contribute toward robust calibration of microscopic traffic flow models for better replicating disordered traffic conditions at signalized intersections.
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Mondal, Satyajit, and Ankit Gupta. "Non-Linear Evaluation Model to Analyze Saturation Flow under Weak-Lane-Disciplined Mixed Traffic Stream." Transportation Research Record: Journal of the Transportation Research Board, March 7, 2021, 036119812199837. http://dx.doi.org/10.1177/0361198121998370.
Full textAbstract:
Saturation flow is an essential parameter for the performance evaluation and signal cycle design of an intersection. However, in a weak-lane-disciplined mixed traffic stream, vehicles (mainly motorized two- and three-wheelers) are more interested in forming queues with the behavior of creeping and infiltration through the larger vehicles for a quick dispersion. Consequently, a high rate of discharge can be found in the first few seconds of green, followed by a wavering discharge pattern to the end of the green period. In this context, the present study frames a non-linear evolutionary model (NLEM) to analyze passenger car unit (PCU) and saturation flow value by minimizing the vehicle encroachment and wavering in discharge for mixed traffic stream. Field traffic data was collected from 10 signalized intersections from three different cities of India. The NLEM considers the vehicle discharge during the saturated green interval in the optimization process to analyze PCU and saturation flow value. The result indicates an appropriate estimation of PCU and saturation flow concerning the Highway Capacity Manual. The discharge profile obtained using the proposed model also specifies the model’s aptness in analyzing the effect of vehicle encroachment and wavering throughout the green period. Thus, the proposed NLEM is probably suitable for analyzing the PCU and saturation flow of an intersection where vehicle interaction is sensitive because of a mixed scenario.
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Schade, Gunnar W., and Geoffrey Roest. "Source apportionment of non-methane hydrocarbons, NOx and H2S data from a central monitoring station in the Eagle Ford shale, Texas." Elementa: Science of the Anthropocene 6 (January 1, 2018). http://dx.doi.org/10.1525/elementa.289.
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Unconventional oil and gas exploration in the US has become a significant new source of atmospheric hydrocarbons. Field measurements and monitoring have been initiated to determine integral effects from this geographically dispersed source in and downwind of shale areas, driven mostly by concerns related to photochemical ozone production. The Texas Commission on Environmental Quality (TCEQ) deployed its first air quality monitor near the Eagle Ford shale in south Texas in summer 2013, followed by a more centrally located monitor in winter 2014/15. Here, we report on the latter monitor’s 2015 data, showing at times extraordinarily high levels of saturated hydrocarbons, similar to earlier findings in this area. Using hydrocarbon ratios, we establish that the dominant sources at this site appear to be oil and gas exploration. A non-negative matrix factorization (NMF) analysis revealed six consistent source factors, of which two were associated with pre-existing local sources from car traffic and industry, three with regional oil and gas exploration, and one with diesel emissions. The dominant source factors were associated with evaporative and fugitive emissions, and with flaring and (diesel-powered) compressor engine emissions. The former is a major source of saturated hydrocarbons while the latter is a major source of NOx and unsaturated hydrocarbons, confirming earlier findings. Due to the rural nature of the site, road traffic is a minor NOx source in this area, and the NMF results support inventory estimates showing oil and gas exploration to be the dominant regional source of NOx emissions. The NMF based source apportionment results also suggests that benzene levels in this rural area in 2015, while comparable to levels in Houston now, were probably three to five times lower before the shale boom.
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Nisumanti, Sartika, and Evina Krisna. "EVALUASI KINERJA JALAN NASIONAL TERHADAP KARAKTERISTIK LALU LINTAS PADA RUAS JALAN NASIONAL KOTA PALEMBANG." JURNAL TEKNO GLOBAL UIGM FAKULTAS TEKNIK 9, no. 1 (August 10, 2020). http://dx.doi.org/10.36982/jtg.v9i1.1082.
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<p><em>The roads</em><em> </em><em>transportation is an </em><em>important infrastructure as one of the land transportation infrastructures for the movement of social activities and to support economic development, specifically in Palembang City. </em><em>The population growth of Palembang City has resulted in an increase in the number of vehicles and highway users. As a result</em><em>, transportation activities in Palembang, especially at Parameswara </em><em>roads are increasing. </em><em>The impact of this, there will be heavy traffic volume, resulting in conflicts on the road, which lead to traffic accidents. </em><em>Therefore</em><em>, there will be congestion and a decrease in the performance of the road speed.</em></p><p><em>The research is conducted at Parameswara Road in Palembang that visually diminished the ability to accommodate the road traffic volume per day, accordingly the effect of traffic that occurs due to the lack of road capacity as the sequence of large volume traffic. The purpose of this study is to determine the capacity and level of road services to carried out the performance value on this road. The method used in the analysis is the Greenshield model, Greenberg, and Underwood. This study explains the maximum volume at peak hour that develop on Monday is between 1561 smp/hour and 1549 smp/hour. Whereas the lowest is around 1225 smp/hour and 1008 smp/hour that occurs on Sunday. Therefore, the analysis of service level on the research years at Parameswara Road depicts the saturated traffic conditions and low starting speed with D service index category and service level analysis at 10 years of planning time projections, the lpda result is from 2022 to 2026, The Parameswara road conditions at E and F service index categories are the traffic jam circumstances and slight speed. Hence, it necessitates constructing a non-plot way at Parameswara Road intersection to tackle this traffic congestion.</em></p><p><strong><em>Keywords</em></strong><em>:<strong> </strong></em><em>Greenshield, Greenberg, Underwood</em>, <em>Road Capacity</em><em>.</em></p>
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Dorlach, T. "The emergence of nutrition warning labels in Latin America." European Journal of Public Health 30, Supplement_5 (September 1, 2020). http://dx.doi.org/10.1093/eurpub/ckaa165.002.
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Abstract Over the last decade, Latin American countries have become leaders in the emerging policy field of front-of-pack nutrition labelling (FOPNL). Recommended by public health experts and the World Health Organization, FOPNL regulations seek to improve the healthiness of population diets and thereby reduce the incidence of overweight and obesity and associated non-communicable diseases, such as diabetes, cancer, and heart diseases. In 2011, Chile passed the world's first comprehensive nutrition labelling law and now prohibits school sales and daytime advertisement of any product labeled “high in” sugar, salt, saturated fats, or calories. Ecuador introduced a mandatory traffic-light labelling scheme in 2014, while Peru, Uruguay, and Mexico introduced Chile-style warning labels since 2018. Several other Latin American countries, including Argentina and Brazil, are currently debating the introduction of mandatory front-of-pack warning labels. In contrast, most countries in the Global North have so far failed to introduce mandatory FOPNL and the European Union even banned its member states from doing so in 2011. This presentation will trace and explain this emergence of FOPNL in Latin America.
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Kim, In-Ju, and Salaheddine Bendak. "Emerging safety risks from public facilities: a field study for ablution spaces in mosques." Facilities ahead-of-print, ahead-of-print (June 21, 2021). http://dx.doi.org/10.1108/f-09-2020-0109.
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Purpose Muslims require an exclusive ablution space for preparing for daily prayers in mosques. Ablution floors seem to entail design challenges since they are often encountered in lubricated conditions from worshippers’ body cleaning manoeuvers. Accordingly, fall risks on saturated surfaces of ablution floors would be a major issue to Muslim worshippers. Thus, the purpose of this study is to investigate the safety status of mosque ablution floors in terms of slip resistance properties and surface texture. Design/methodology/approach Fifteen mosques in Dubai and Sharjah cities of the UAE were randomly chosen to investigate the safety conditions of ablution spaces. In-situ slip-resistance properties and surface finishes of each ablution floor were measured under clean, wet, and soapy conditions at two different volumes of traffic areas: heavy- and non-traffic. Surface finishes of ablution floors were also measured and analysed. Findings Outcomes from this study evidently showed that the inspected ablution floors were not currently protected against falls, especially under wet and soapy environments. Surface analyses identified that the present ablution floors have extremely flat surfaces (? 2 µm in the Ra parameter) so they require significant improvements against fall risks. Originality/value Regardless of the magnitude of this issue, it is scarce to attain any published study on ablution floors’ fall incidence and avoidance plans in the scientific and technical literature. There are also no officially and publicly available data on fall incidents from ablution places in mosques. Findings from this study would be a great step forward to establish safer ablution floors for Muslim prayers.
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Balakrishna, M. N., Fouad Mohammad, Robert Evans, and M. M. Rahman. "EVALUATION OF CHLORIDE ABSORPTION IN PRE-CONDITIONED CONCRETE CUBES." Malaysian Journal of Civil Engineering 30, no. 2 (August 5, 2018). http://dx.doi.org/10.11113/mjce.v30n2.473.
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The chloride contamination will occur from an application of de-icing salts. It was confirmed that, the application of de-icing salts caused a significant reduction in structural and serviceability reliabilities. The chemicals used in the snow and ice control operations (de-icers) may cause corrosion damage to the transportation infrastructure such as reinforced/pre-stressed concrete structures/steel bridges. There are many ways to manage the corrosive effects of de-icers, such as selection of high-quality concrete, adequate concrete cover and alternative reinforcement, control of an ingress and accumulation of deleterious species, injection of beneficial species into concrete, and use of non-corrosive de-icer alternatives and optimal application rates. In fact, snow and ice on streets and highway are a major threat to human life and limb. Traffic accidents and fatalities climb as snow and ice reduce traction on roadways. Lengthened emergency response times create additional risks for persons in urgent need of medical care, particularly in cases of heart attacks, burns, childbirth and poisoning. Thus the de-icing salts are necessary to provide safe winter driving conditions and save lives by preventing the freezing of a layer of ice on concrete infrastructure. However, the safety and sense of comfort provided by these salts is not without a price, as these salts can greatly contribute to the degradation and decay of reinforced concrete transportation systems. An importance of chloride concentration as a durability-based material property has received greater attention only after the revelation that chloride-induced corrosion is the major problem for concrete durability. Therefore, there is a need to quantify the chloride concentration in concrete which is of paramount importance. The present research work was made an attempt to interpret the concrete chloride absorption in ordered to characterize the different concrete mixtures design for in case of pre-conditioned concrete cubes such as dry/fully/partially saturated condition which was salt ponded with chloride solution for about 160 days. Thus the objectives of this present research are such as: First, this research will examine an influence of conditioning such as dry/fully/partially saturated condition on the results of chloride absorption performed on concrete cubes with different mixtures proportion in which slump, and w/c ratio value was varied with constant compressive strength as in the First case and compressive strength, and w/c ratio value varied with constant slump as in the Second case. Seventy-two concrete cubes (100 mm3) with Grades of concrete ranges from 25 to 40 N/mm2 were prepared and evaluate the chloride absorption under different exposure condition. It’s concluded from the results that, in dry/saturated conditioned concrete cubes, the chloride absorption value was increased in all designed mixtures type. Similarly, average chloride absorption was decreased in solvent/water based impregnation DCC/PSC/FSC cubes as when compared to control DCC/PSC/FSC cubes for constant higher compressive strength and varied slump value as well as varied compressive strength and constant slump value. Whereas average chloride absorption was increased in solvent/ water based impregnation DCC/PSC/FSC cubes for lesser compressive strength and constant slump value as when compared to constant higher compressive strength and varied slump value and the chloride absorption was goes on decreases with an increased compressive strength and constant slump value.