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Viewing 181 to 210 of 8633
2017-03-28
Technical Paper
2017-01-1370
Hiroyuki Hara, Masaaki Kawauchi, Masayuki Katayama, Noriyuki Iwamori
Abstract Driving is an action that depends strongly on visual information. For displays in the cockpit, a combination of “ease of viewing” to inform the driver of danger early and “annoyance reduction” to avoid drops in the driver’s perception is needed. In this study, we tried to capture “ease of viewing” and “annoyance” in one fixed-quantity indicator. We took up a Camera Monitor System (CMS) as the subject and analyzed the effect that annoyance with the display used in CMSs has on driving behavior. Based on our analysis, we hypothesize that evaluating carelessness in viewing behavior is related evaluating to annoyance. Next, we chose a Detection Response Task (DRT) technique as a method to evaluate driving behavior influenced by this annoyance.
2017-03-28
Technical Paper
2017-01-1366
Jeffrey Muttart, Swaroop Dinakar, Jeffrey Suway, Michael Kuzel, Timothy Maloney, Wayne Biever, Toby Terpstra, Tilo Voitel, David Cavanaugh, T.J. Harms
Abstract Collision statistics show that more than half of all pedestrian fatalities caused by vehicles occur at night. The recognition of objects at night is a crucial component in driver responses and in preventing nighttime pedestrian accidents. To investigate the root cause of this fact pattern, Richard Blackwell conducted a series of experiments in the 1950s through 1970s to evaluate whether restricted viewing time can be used as a surrogate for the imperfect information available to drivers at night. The authors build on these findings and incorporate the responses of drivers to objects in the road at night found in the SHRP-2 naturalistic database. A closed road outdoor study and an indoor study were conducted using an automatic shutter system to limit observation time to approximately ¼ of a second. Results from these limited exposure time studies showed a positive correlation to naturalistic responses, providing a validation of the time-limited exposure technique.
2017-03-28
Journal Article
2017-01-1213
Yilin Yin, Zhong Zheng, Song-Yul Choe
Abstract Analysis of thermal behavior of Lithium ion battery is one of crucial issues to ensure a safe and durable operation. Temperature is the physical quantity that is widely used for analysis, but limited for accurate investigations of behavior of heat generation of battery because of sensitivities affected by heat transfer in experiments. Calorimeter available commercially is widely used to measure the heat generation of battery, but does not follow required dynamics because of a relatively large thermal time constant given by cavity and a limited heat transfer capability. In this paper, we proposed a highly dynamic calorimeter that was constructed using two thermoelectric devices (TEMs). For the design of the calorimeter and its calibration, a printed circuit board (PCB) with the same size as the battery was used as a dummy load to generate controlled heat.
2017-03-28
Journal Article
2017-01-1215
Peter Haussmann, Joachim Melbert
Abstract Battery safety is the most critical requirement for the energy storage systems in hybrid and electric vehicles. The allowable battery temperature is limited with respect to the battery chemistry in order to avoid the risk of thermal runaway. Battery temperature monitoring is already implemented in electric vehicles, however only cell surface temperature can be measured at reasonable cost using conventional sensors. The internal cell temperature may exceed the surface temperature significantly at high current due to the finite internal electrical and thermal cell resistance. In this work, a novel approach for internal cell temperature measurement is proposed applying on board impedance spectroscopy. The method considers the temperature coefficient of the complex internal cell impedance. It can be observed by current and voltage measurements as usually performed by standard battery management systems.
2017-03-28
Technical Paper
2017-01-0188
Yoichiro Higuchi, Hiroyuki Kobayashi, Zhiwei Shan, Mikiharu Kuwahara, Yoshiharu Endo, Yuha Nakajima
Abstract As vehicle emission regulations become increasingly rigorous, the automotive industry is accelerating the development of electrified vehicle platforms such as Battery Electric Vehicles (BEV) and Plug-in Hybrid Electric Vehicles (PHEV). Since the available waste heat from these vehicles is limited, additional heat sources such as electric heaters are needed for cabin heating operation. The use of a heat pump system is one of the solutions to improve EV driving range at cold ambient conditions. In this study, an efficient gas-injection heat pump system has been developed, which achieves high cabin heating performance at low ambient temperature and dehumidification operation without the assistance of electric heaters in ’17 model year Prius Prime.
2017-03-14
Journal Article
2017-01-9276
Joseph K. Ausserer, Marc D. Polanka, Jacob A. Baranski, Keith D. Grinstead, Paul J. Litke
Abstract The rapid expansion of the market for remotely piloted aircraft (RPA) includes a particular interest in 10-25 kg vehicles for monitoring, surveillance, and reconnaissance. Power-plant options for these aircraft are often 10-100 cm3 internal combustion engines. Both power and fuel conversion efficiency decrease with increasing rapidity in the aforementioned size range. Fuel conversion efficiency decreases from ∼30% for conventional-scale engines (>100 cm3 displacement) to <5% for micro glow-fuel engines (<10 cm3 displacement), while brake mean effective pressure decreases from >10 bar (>100 cm3) to <4 bar (<10 cm3). Based on research documented in the literature, the losses responsible for the increase in the rate of decreasing performance cannot be clearly defined.
2017-01-10
Technical Paper
2017-26-0262
Neelakandan Kandasamy, Koundinya Narasimha Kota, Prasad Joshi
Abstract The structure of a vehicle is capable of absorbing a significant amount of heat when exposed to hot climate conditions. 50-70% of this heat penetrates through the glazing and raises both the internal cabin air temperature and the interior trim surface temperature. When driving away, the air conditioning system has to be capable of removing this heat in a timely manner, such that the occupant’s time to comfort will be achieved in an acceptable period [1]. When we reduce the amount of heat absorbed, the discomfort in the cabin can be reduced. A 1D/3D based integrated computational methodology is developed to evaluate the impact of vehicle orientation on cabin climate control system performance and human comfort in this paper. Additionally, effects of glazing material and blinds opening/closing are analyzed to access the occupant thermal comfort during initial and final time AC pull down test.
2017-01-10
Technical Paper
2017-26-0370
G. Meenakshi, Nishit Jain, Sandeep Mandal
Abstract Automobile industry is shifting its focus from conventional fuel vehicles to NexGen vehicles. The NexGen vehicles have electrical components to propel the vehicle apart from mechanical system. These vehicles have a goal of achieving better fuel efficiency along with reduced emissions making it customer as well as environment friendly. Idle start-stop is a key feature of NexGen vehicles, where, the Engine ECU switches to engine stop mode while idling to cut the fuel consumption and increase fuel efficiency. Engine restarts when there is an input from driver to run the vehicle. There is always a clash between the Engine ECU and automatic climate control unit (Auto-AC) either to enter idle stop mode for better fuel efficiency or inhibit idle stop mode to keep the compressor running for driver comfort. This clash can be resolved in two ways: 1 Hardware change and,2 Software change Hardware change leads to increase in cost, validation effort and time.
2017-01-10
Technical Paper
2017-26-0237
Bhupesh Agrawal, Mohit Varma, Chandrashekhar Sewatkar
Abstract High temperatures in the surface mounted permanent magnet (SMPM) synchronous motor adversely affect the power output at the motor shaft. Temperature rise may lead to winding insulation failure, permanent demagnetization of magnets and encoder electronics failure. Prediction and management of temperatures at different locations in the motor should be done right at the design stage to avoid such failures in the motor. The present work is focused on the creation of Lumped Parameter Thermal Network (LPTN) and CFD models of SMPM synchronous motor to predict the temperature distribution in the motor parts. LPTN models were created in Motor-CAD and Simulink which are suitable for parameter sensitivity analysis and getting quick results. Air is assumed to be a cooling medium to extract heat from the outer surface of motor. CFD models were useful in providing elaborate temperature distribution and also locating the hot-spots. Correlation models by both the methods, viz.
2017-01-10
Technical Paper
2017-26-0087
Prasad B Warule, Vaibhav V Jadhav
Abstract Hybridization of vehicle drive train is an important step to increase energy security, reduce crude oil import, improvement of air quality and GHG reduction. Heavy traffic congestion poses a great challenge in improvement of fuel economy. Nowadays urban climatic condition forces the passenger to keep air-conditioning (AC) on; thus further decreasing the fuel economy. In a typical urban drive; the vehicle commutes with low speed forcing IC Engine to run in its low efficiency operational points. Further it is characterized by frequent start-stop and crawling. It has been observed that the power consumption for AC is comparable to that required for the vehicle propulsion. Hence the AC on condition with propelling vehicle demands higher power from engine creating a challenge for fuel economy improvement.
2017-01-10
Technical Paper
2017-26-0029
Shubham Saxena, Mudassir Ahmed
Abstract Higher fuel economy of the vehicle is a critical concern in automobile industry. Traditional internal combustion (IC) engines waste a large portion of the available fuel energy as heat loss via exhaust gas. This proposal aims at recovering the available exhaust heat of the IC engines using stirling engine (SE) as an add-on device. SE is a type of cyclic heat engine which operates by compression and expansion of the working fluid, at different temperature levels resulting in a conversion of the heat energy into mechanical work. A thermodynamic analysis is performed on the chosen beta SE rhombic drive configuration with different combinations of design parameters like working fluid mass, total dead volume, thermal resistance, and hot side and cold side temperatures. A regenerator temperature model is developed to account for first law consistency in the regenerator section of SE, along with heat transfer in accordance with mass flow within the regenerator.
2017-01-10
Technical Paper
2017-26-0150
Abhijeet Chothave, Yashwant Mohite, Vinay Poal, Phaneendra Pamarthi
Abstract In present day passenger cars, Mobile Air Conditioning (MAC) system is one of the essential features due to rise in overall ambient temperatures and comfort expectation of customers. During the development of MAC system, the focus is on cooling capacity of system for maintaining in-cabin temperatures. However, parameters like solar radiation, air velocities at occupant, relative humidity, metabolic rate and clothing of occupants also influence occupant’s thermal comfort and normally not considered in design of the MAC system. Subjective method is used to evaluate thermal comfort inside vehicle cabin which depends mainly on human psychology. To better understand the effect and minimize the human psychological factors a large sample of people are required. That process of evaluating the comfort inside the vehicle cabin is not only time consuming but also impractical.
2017-01-10
Technical Paper
2017-26-0098
Riaz Ahamed, Koorma Rao Vavilapalli, Clement Jones, V P Abhijith
Abstract Major decision driving constraints in the automobile sector is space and cost. With the advent of electric vehicles, these constraints apply for electric drive motor also. For applications involving neighborhood electric vehicles (NEV), the challenges become manifold with target cost of complete drivetrain system, including motor, controller & transmission, being very low. This and application of low cost axle mount drive systems prohibits usage of liquid cooled systems. In this scenario, ways to improve thermal performance of motor can be - to reduce heat generation, increase heat conduction and to increase heat rejection so that temperature of winding is kept under thermal limit of insulation used. Major area of thermal hotspots in the motor is at the end windings where direct conductive path to the housing is less. In this paper, thermal performance of the motor is improved by introducing vacuum encapsulation at the end winding thereby increasing net heat conduction.
2017-01-10
Journal Article
2017-26-0364
Igor Gritsuk, Vladimir Volkov, Vasyl Mateichyk, Yurii Gutarevych, Mykola Tsiuman, Nataliia Goridko
Abstract The article suggests the results of experimental and theoretical studies of the engine heating system with a phase-transitional thermal accumulator when the vehicle is in motion in a driving cycle. The aim of the study is to evaluate the efficiency of the vehicle heating system within thermal accumulator and catalytic converter under operating conditions. The peculiarity of the presented system is that it uses thermal energy of exhaust gases to accumulate energy during engine operation. The article describes the methodology to evaluate vehicle fuel consumption and emission in the driving cycle according to the UNECE Regulation № 83-05. The methodology takes into account the environmental parameters, road conditions, the design parameters of the vehicle, the modes of its motion, thermal state of the engine cooling system and the catalytic converter.
2017-01-10
Journal Article
2017-26-0073
B Ashok, K Nantha Gopal, Thundil Karuppa Raj Rajagopal, Sushrut Alagiasingam, Suryakumar Appu, Aravind Murugan
Abstract With the alarming increase in vehicular population, there is depletion of fossil fuel availability. Hence to overcome the difficulties, alternative fuels are tested and used in parts of the world. One of the difficulties with usage of alternate fuels is their high viscosity in comparison to fossil fuels. To overcome this, preheating of biofuel is a good option as it makes the fuel less viscous. In our research, we have used a helical coil heat exchanger to preheat the inlet fuel using the engine’s exhaust gas, making the system more sustainable since no external energy is used. In order to evaluate the effectiveness of preheating device a simulation study has been carried for the ethanol based biofuels. For simulation work, a set of boundary conditions has been arrived based on the experimental analysis. The results from the experiment such as velocity of air and fuel inlet were utilized as input for simulation work.
2017-01-10
Technical Paper
2017-26-0180
Swaminathan Ramaswamy, Christophe Schorsch, Mario Kolar
Abstract Automotive OEMs are adapting various “green” technologies to meet the upcoming and anticipated regulations for reducing direct and indirect GHG emissions equivalent to CO2. Using compact devices and lightweight components on the aggregates, OEMs get the benefit of carbon credits towards their contribution in reducing CO2 emissions. With regards to the HVAC systems, enhancements such as ultra-low permeation hose assemblies and adoption of low GWP refrigerant have shown promising results in reducing the direct GHG emissions by controlling refrigerant permeation & indirect GHG emissions by using compact and high efficiency compressors, compact heat exchangers, and other technologies that contribute to weight reduction and ultimately impact CO2 emissions. Traditional AC lines are routed/installed in space that accommodates the relative movement between the engine and chassis by connecting the various parts.
2016-11-08
Technical Paper
2016-32-0008
Balagovind Nandakumar Kartha, Srikanth Vijaykumar, Pramod Reddemreddy
Abstract Today, nations are in the path of low-emission transformation mandating stricter emission norms with periodic revisions. With the expected introduction of Bharath Stage VI (BS VI) for two wheelers in India by 2020, limitation in primary pollutants namely - Carbon Monoxide (CO), Total Hydro-Carbons (THC) and Nitrogen Oxides (NOx) are reduced by 50%, 75% and 85% respectively in comparison to the existing Bharath Stage IV. The original equipment manufacturers (OEMs) are identifying measures to improve the overall efficiency and raw emissions from the engine through strategies like multi-spark configurations, improved charge induction concepts, liquid cooling, lean combustion etc. With end user demands for performance, low end torque, high power to displacement ratio, quick acceleration and fuel efficiency, the balance with the emission regulation is expected to be challenging.
2016-11-08
Technical Paper
2016-32-0081
Giovanni Vichi, Michele Becciani, Isacco Stiaccini, Giovanni Ferrara, Lorenzo Ferrari, Alessandro Bellissima, Go Asai
Abstract For the development of a very high efficiency engine, the continuous monitoring of the engine operating conditions is needed. Moreover, the early detection of engine faults is fundamental in order to take appropriate corrective actions and avoid malfunctioning and failures. The in-cylinder pressure is the most direct parameter associated to the engine thermodynamic cycle. The cost and the intrusiveness of the dynamic pressure sensor and the harsh operating condition that limits its life-time, make the direct measurement of the in-cylinder pressure not suitable for mass production applications. Consequently, research is oriented on the measurement of physical phenomena linked to the thermodynamic cycle to obtain useful information for the ICE control.
2016-11-08
Technical Paper
2016-32-0085
Giovanni Vichi, Michele Becciani, Isacco Stiaccini, Giovanni Ferrara, Lorenzo Ferrari, Alessandro Bellissima, Go Asai
Abstract For the development of a very high efficiency engine, the continuous monitoring of the engine operating conditions is needed. Moreover, the early detection of engine faults is fundamental in order to take appropriate corrective actions and avoid malfunctioning and failures. The in-cylinder pressure is the most direct parameter associated to the engine thermodynamic cycle. The cost and the intrusiveness of the dynamic pressure sensor and the harsh operating condition that limits its life-time, make the direct measurement of the in-cylinder pressure not suitable for mass production applications. Consequently, research is oriented on the measurement of physical phenomena linked to the thermodynamic cycle to obtain useful information for the ICE control.
2016-11-08
Technical Paper
2016-32-0079
Daisuke Fukui, Yoshinari Ninomiya
Abstract With the remarkable rise of gas prices and global air pollution, measures to improve fuel efficiency and reduce emissions have become urgently needed in the motorcycle industry, as in the automobile industry. One approach is to improve the thermal efficiency of the engine, and much research and development has been done for many years on this subject. Community-based small motorcycles require both high mobility and fuel efficiency in developed and developing countries. Drivability and emission control of recreation and sports motorcycles are also needed. However, when developing engines for small motorcycles, due to differences in engine speed range, driving load range, devices for driving and emission control, market prices, and infrastructure, some different approaches from those for automobile engines with their many advanced technologies are needed.
2016-11-08
Technical Paper
2016-32-0077
Roland Baar, Valerius Boxberger, Maike Sophie Gern
Abstract Two-cylinder engines not only have special demands concerning uniformity and dynamics of oscillating masses and firing order, but also place very different demands on the turbocharger. With two-cylinder engines, the pulsating influence grows and changes the operation of the turbine. In this paper different boosting technologies are compared in small engine applications. Besides turbochargers the potentials and limits of superchargers and electric chargers are compared as well as their combinations. These technologies show differences concerning power supply, operation range and efficiency, and these effects have different implications in small engines. The efficiency of a turbo compressor, for example decreases, rapidly for small dimensions. Results from experiments and engine process simulations are shown based on a two-cylinder engine of 0.8l displacement. The operating condition of a turbocharger turbine in a two-cylinder engine is very specific due to exhaust pulsations.
2016-11-08
Journal Article
2016-32-0028
Pascal Piecha, Philipp Bruckner, Stephan Schmidt, Roland Kirchberger, Florian Schumann, Stephan Meyer, Tim Gegg, Stefan Leiber
Abstract Small displacement two-stroke engines are widely used as affordable and low-maintenance propulsion systems for motorcycles, scooters, hand-held power tools and others. In recent years, considerable progress regarding emission reduction has been reached. Nevertheless, a further improvement of two-stroke engines is necessary to cover protection of health and environment. In addition, the shortage of fossil fuel resources and the anthropogenic climate change call for a sensual use of natural resources and therefore, the fuel consumption and engine efficiency needs to be improved. With the application of suitable analyses methods it is possible to find improving potential of the working processes of these engines. The thermodynamic loss analysis is a frequently applied method to examine the working process and is universally adaptable.
2016-11-08
Journal Article
2016-32-0033
Tiago J. Costa, Mark Nickerson, Daniele Littera, Jorge Martins, Alexander Shkolnik, Nikolay Shkolnik, Francisco Brito
Abstract This paper describes predictive models and validation experiments used to quantify the in-chamber heat transfer of LiquidPiston’s rotary 70cc SI “XMv3” engine. The XMv3 engine is air cooled, with separate cooling flow paths for the stationary parts and the rotor. The heat transfer rate to the stationary parts was measured by thermal energy balance of that circuit’s cooling air. However, because the rotor’s cooling air mixes internally with the engine’s exhaust gas, a similar procedure was not practical for the rotor circuit. Instead, a CONVERGE CFD model was developed, and used together with GT-POWER to derive boundary conditions to estimate a ratio between rotor and stationary parts heat transfer, thus allowing estimation of rotor and total heat losses. For both cases studied (5000 and 9000 rpm under full load), the rotor’s heat loss was found to be ∼60% that of the stationary parts, and overall heat losses were less than 35% of supplied fuel energy.
2016-11-08
Journal Article
2016-32-0034
Stephan Jandl, Hans-Juergen Schacht, Stephan Schmidt, Ute Dawin, Armin Kölmel, Stefan Leiber
Abstract Worldwide increasing energy consumption, decreasing energy resources and continuous restriction of emission legislation cause a rethinking in the development of internal combustion engines and fuels. Alternative renewable fuels, so called bio-fuels, have the potential to contribute to environmentally friendly propulsion systems. This study concentrates on the usage of alcohol fuels like ethanol, methanol and butanol in non-automotive high power engines, handheld power tools and garden equipment with the focus on mixture formation and cold start capability. Although bio-fuels have been investigated intensely for the use in automotive applications yet, the different propulsion systems and operation scenarios of nonautomotive applications raise the need for specific research. A zero dimensional vaporization model has been set up to calculate the connections between physical properties and mixture formation.
2016-11-07
Technical Paper
2016-22-0006
John R. Humm, Narayan Yoganandan, Frank A. Pintar, Richard L. DeWeese, David M. Moorcroft, Amanda M. Taylor, Brian Peterson
The objective of the present exploratory study is to understand occupant responses in oblique and side-facing seats in the aviation environment, which are increasingly installed in modern aircrafts. Sled tests were conducted using intact Post Mortem Human Surrogates (PMHS) seated in custom seats approximating standard aircraft geometry. End conditions were selected to represent candidate aviation seat and restraint configurations. Three-dimensional head center-of-gravity linear accelerations, head angular velocities, and linear accelerations of the T1, T6, and T12 spinous processes, and sacrum were obtained. Three-dimensional kinematics relative to the seat were obtained from retroreflective targets attached to the head, T1, T6, T12, and sacrum. All specimens sustained spinal injuries, although variations existed by vertebral level.
2016-11-07
Technical Paper
2016-22-0009
Hollie A. Pietsch, Kelly E. Bosch, David R. Weyland, E. Meade Spratley, Kyvory A. Henderson, Robert S. Salzar, Terrance A. Smith, Brandon M. Sagara, Constantine K. Demetropoulos, Christopher J. Dooley, Andrew C. Merkle
Three laboratory simulated sub-injurious under-body blast (UBB) test conditions were conducted with whole-body Post Mortem Human Surrogates (PMHS) and the Warrior Assessment Injury Manikin (WIAMan) Technology Demonstrator (TD) to establish and assess UBB biofidelity of the WIAMan TD. Test conditions included a rigid floor and rigid seat with independently varied pulses. On the floor, peak velocities of 4 m/s and 6 m/s were applied with a 5 ms time to peak (TTP). The seat peak velocity was 4 m/s with varied TTP of 5 and 10 ms. Tests were conducted with and without personal protective equipment (PPE). PMHS response data was compiled into preliminary biofidelity response corridors (BRCs), which served as evaluation metrics for the WIAMan TD. Each WIAMan TD response was evaluated against the PMHS preliminary BRC for the loading and unloading phase of the signal time history using Correlation Analysis (CORA) software to assign a numerical score between 0 and 1.
2016-10-28
Technical Paper
Interiors, Cabins and Cockpits
2016-10-25
Technical Paper
2016-36-0429
Michelle Pelka, Edgar L. Baptista, Marcos R. de Lima, Rodrigo G. Albino, Camilo A. Adas
Abstract The methodology consisted in comparing two different techniques for dynamic evaluation of vehicle’s thermal comfort, using the obtained data from a relatively simple thermal stress equipment (ISO 7243) and correlating it to the results from a complex dedicated thermal comfort equipment (ISO 7730 - ISO 14505). Therefore, it was necessary to add sensors and develop a new program using the algorithm provided by the standard. The results showed that it is possible to use this correlation with good approximation for a quick analysis, with simpler instrumentation, reduced complexity and lower cost of the measurement.
2016-10-25
Technical Paper
2016-36-0351
Ricardo Gonçalves, Reinaldo dos Santos
Abstract Increasingly, the auto industry has been challenged to meet its financial needs to remain competitive. Customer comfort needs in regard to the Vehicle Interior Noise levels are also remarkable. The application of fixed displacement air conditioning compressors and low cost exhaust system in vehicles to meet the programs cost targets generated a series of notorious and undesirable effects to the customer. The noise perception of the compressor coupling during its operation cycle is one of them. This happens in some specific situations and varies with weather and engine operating conditions. The vehicle used in this study presented a boom noise coming from the exhaust tailpipe during the AC compressor coupling phase. This noise was attenuated to satisfactory levels in regard to consumer perception with only a change in engine calibration strategy.
2016-10-25
Technical Paper
2016-36-0262
Edney Rejowski, Juliano Pallaoro de Souza, Rafael Bettini Rabello
Abstract Engine development activities are being driven forward primarily by the challenge of continuing to reduce CO2 and exhaust emissions. From the piston/liner system it is well known that Lube Oil Consumption (LOC) is affected by the bore distortion occurrences within Internal Combustion Engines (ICE) that usually demands a redesign on the piston ring pack not in favor to reduce friction losses. This article shows a potential solution to reduce bore distortion and oil evaporation through more efficient heat dissipation from combustion chamber to engine cooling system in a modern aluminum Spark Ignition (SI) block. Electroplated nickel coating applied to the external cast iron surface previous to the casting process enable a metallurgical diffusion layer with the aluminum block material and therefore improve heat conductivity in fired operation conditions compared to conventional cast iron liners.
Viewing 181 to 210 of 8633