In 2020, an extended vehicle hold-up on Kan-Etsu Expressway was caused by heavy snowfall. To avoid such vehicle hold-ups, the expressway company provides highway information to encourage users to make wide-area detours and refrain from leaving the highway during heavy snowfalls. In this study, we conducted an SP survey based on a web-based questionnaire to clarify the relationship between the provision of information and users’ behaviour during heavy snowfalls. We analyzed the effects of individual attributes, i.e., frequency of highway use and experience on driving snow-covered roads, the accuracy and timing of highway information, and uncertainties, i.e., the probability of road closures and variation in travel time, on users’ behaviour by estimating a nested logit model. The analysis revealed that driving experience on snow-covered roads, the provision of highly accurate information, and the early provision of information encourage the user’s behaviour such as taking a wide detour or switching to a different mode of transportation. Further, it was also shown that there were differences in the user's behaviour depending on the purpose of travel.

Route buses, which are familiar with public transportation to people, should be easy to use for everyone. However, many people often get on a bus with psychological resistance because basic information on bus usage is not very clearly announced. Therefore, this paper focus on bus route maps and, in particular, on the way the background was drawn. In order to clarify the user evaluation of each type of route map for each complexity of the route network, we first collected bus route maps from all over Japan and identified the design characteristics of both the route maps with maps and the deformed route maps. We then conducted an evaluation experiment using route search to determine whether the mapped or deformed route maps are easier to understand.

Currently, on-street parking is considered a problem because of its negative impact on the smoothness of traffic. In the future, on-street parking is expected to further increase due to the spread of e-commerce, ride-sharing, and autonomous vehicles. Therefore, flexible curbside utilization methods are required to accommodate a variety of uses in a limited space. The purpose of this study is to examine the future vision of curbside and to propose a planning and evaluation procedure for curbside to cope with a society in which autonomous vehicles, etc. have become widespread. As a result of the analysis, it was quantitatively clarified from the case study that the smoothness of traffic and the effective use of space can be improved by restricting parking. On the other hand, it was shown that in order to maintain smoothness, parking demand cannot be addressed in some locations, and off-street facilities are necessary.

With the increasing popularity of time-specified services in the parcel delivery industry, it is becoming increasingly important to understand the impact of time constraints on small-lot logistics. This study focuses on the inter-city transportation part of small-lot logistics and proposes an optimization model that introduces departure and arrival time constraints into the hub network design problem (HNDP), which determines the network geometry. The results show that the model can represent the phenomena of detouring and consolidation on the network as expected, and that a trade-off relationship appears between the strength of the time constraint and the cost of the network.

Intercity passenger transportation is characterized by seasonal fluctuations in demand. There is a risk of idle-ness in the off-season and a decrease in the efficiency of the assets if the amount of rolling stocks such as vehicles and personnel is adjusted to the busy season. This study proposes a method to quantitatively analyze the effects of idle-avoidance measures using an optimization model. Based on the consumer surplus maximization model of the previous study, multiple seasons with different demand patterns are taken into account, and the operation links in the network, operating volume, and fare are treated as season-specific variables. We consider the combination of the interoperability of vehicles and the seasonal changes in fares as idle avoidance measures, and compare the values of total consumer surplus and other factors to assess the effect of them.

Roadside stations called ‘Michi-no-eki’ are facilities for enhancing functions such as parking and resting along ordinary roads in Japan. However, there is no concrete index for the optimal placement of rest facilities such as roadside stations in the whole road network, and there are few researches about that. Therefore, in this study, we model the rest place selection behavior of ordinary road users for rest facility placement evaluation. This model calculated the utility as an evaluation index considering the combination of rest facilities to stop by for any trip, and constructed a framework in which the model parameters can be derived from the SP data. In addition, as a result of verification of its practicality, it was confirmed that the stop-by pattern with greater utility tends to be selected, and the structure of the model is appropriate.

In this study, the authors reviewed the existing manuals and guides on local public transportation and the unique cases of their introduction and extracted the issues that local governments are facing in the field. Based on the reviews, we conducted a questionnaire survey of municipalities for observing effective factors evaluated by each municipality for introduction of community bus and DRT. In conclusion, it was observed that the effective factors of community bus such as target trips, consideration of operation, demand-perspective, setting objective and monitoring were taken into consideration. On the other hand, effective factors on DRT are indicated only as setting objective and monitoring. Therefore, the author found that there are different effective factors between modes because of operational characteristics and demand characteristics.

It is difficult to assess the local public transportation only with the ridership and freight revenues in mountainous area. For sustaining local public transportation in mountainous area, it is important to clarify the effect of local public transportation on settlement for older-non-users. Therefore, this study clarified the effect of conducting local public transportation on settlement for older-non-users by intention to use local public transportation in mountainous area. As a result, it is suggested that improving local public transportation service promotes the consciousness of settlement for older-non-users who intends to use the local public transportation in the future. And then, it is also suggested that the degradation of local public transportation service reduces the consciousness of settlement for older-non-users who intend not to use the local public transportation in the future.

The Parking Development Plan is a statutory plan based on Article 4 of the Parking Act, and is an important plan that sets the basic policy and target amount of parking development for each municipality. In order to set the target amount of development, it is assumed that it will be necessary to forecast future parking demand, but there is no formalized method for this. In addition, in light of the recent increase in parking supply, mainly due to the increase in the number of mandatory parking spaces, it can be pointed out that future demand forecasts may not be necessary. The purpose of this study is to categorize these methods by collecting parking facility development plans published on the Internet and investigating their descriptions of future parking demand forecasts, and to organize issues related to future parking demand forecasting methods.

Global aviation demand is increasing year by year, especially in emerging economies such as Asia and South America, and urgent functional enhancement is a top priority at metropolitan airports. On the other hand, in recent years, with the rapid changes in social conditions and the natural environment, countermeasures against environmental impacts have begun to be required. Overseas, the development of software such as the introduction of an efficient control processing system is progressing, and the effects of improving the workload of controllers, reducing fuel consumption, and reducing the environmental load are being achieved. Moreover, in Japan, the Yokota airspace, which is an entry restricted area, and the metropolitan area airspace are not being effectively utilized due to the influence of noise. The purpose of this study is to study a new flight route utilizing the airspace of the Tokyo metropolitan area for Haneda Airport and analyze its effect. Therefore, we focused on the Point Merge System as an advanced control operation method introduced in Japan in recent years, and clarified the actual operation at Haneda Airport. Furthermore, based on the results, after improving the airspace simulator developed in the previous research and verifying the reproducibility, we conducted a simulation analysis when utilizing the metropolitan area airspace for flights arriving on the west side. A basic study of the effect was conducted.

Bicycles are widely used in Japan by people of all age groups in daily usage. Responding to the COVID-19 pandemic, bicycle will play a central role in commuting and traveling instead of using trains and other public transportation. However, the safety of bicycle facilities in Japan are still far behind comparing to the countries developed in Europe and America. The reason for this is that, a car traffic priority is still common in Japanese road planning. In this study, in order to examine the possibility of road space reallocation in Japan, we analyze the effect of three to two-lane road space reallocation considering the environment of bicycle facilities. The result shows the reallocation of road space has little negative influence on the traffic flow by estimating travel time, travel speed, conflict frequency and carbon dioxide emission.

Although the roadway space for bicycle traffic has been improved in recent years, there are many situations in which bicycles and pedestrians share the same space. In particular, when bicycles overtake pedestrians, there are many cases of confusion and a decreased sense of security. To improve this situation, appropriate traffic communication between pedestrians and bicycles is considered to be effective, but there is no established traffic communication method. In this study, we developed an experimental apparatus for two-player cooperative games with movies, and analyzed the social acceptability of several communication methods when they are established as social rules. The results showed that “passing without doing anything”, which is currently prevalent, tends to be unacceptable, while bells, alarms (bells), and talking to others were highly acceptable. However, since there were negative opinions depending on the situation and individual attributes, the optimal method for each situation could not be found in a unified manner.

Improving the safety, efficiency and smoothness of pedestrian traffic flow in urban areas is an important issue from various perspectives, such as promoting walkability and livability. This requires an appropriate understanding of the nature of pedestrian traffic flow. Factors that influence pedestrian behavior have been extensively studied. In this study, we focus on background music (BGM) as one of the influential factors. It is well known that music affects human emotion, which brings about behavioral alteration. According to previous research, individual walking speed increases when BGM tempo increases. However, whether and how emotional aspects of music influence the pedestrian crowd flow, in which individual pedestrians interact with one another, is still unknown. If emotional aspects of music influence the macroscopic characteristics of pedestrian flow, music could be employed as a tool for managing the pedestrian crowd and boosting its efficiency. In this study, we investigate the impact of emotional aspects of BGM on the macroscopic characteristics of pedestrian flow by conducting a walking experiment under the influence of various forms of BGM. As a result of the experiment, it is found that i) positiveness and easiness can be used to explain the components of music, ii) BGM affects the shape of the diagrams depicting a relationship between density and average speed, iii) there are statistically significant variations in average speed and average flow rate under free-flow and congested-flow condition, and iv) there are tendencies that the traffic capacity increases as the BGM positiveness increases.

In recent years, street design improvement has been required for both functions of transport and activity, the effectiveness of which can be affected by the road usage of cars and pedestrians. Accordingly, the purpose of this study is to analyze the impacts of traffic density, including cars and pedestrians, on the street design evaluation. First, based on the traffic density index, various streetscapes are produced with CG. Then, a questionnaire survey is conducted to evaluate the street design with the different patterns of traffic density. As a result, The traffic density improved the enjoyment through the large number of people, and the interaction related to the traffic density also showed a gradual decrease effect, indicating that it is important to improve the space in consideration of the road usage of cars and pedestrians.

The walkability is a significant indicator of livability of urban areas, which is determined by various factors of street conditions. The security of streets has direct impact on pedestrians’ walking experience and relates to incidence of actual crimes or aggressive behaviors against pedestrians. In order to improve the security level of urban streets and build a comfortable and safe walking environment for citizens, on one hand, it should be figured out what the influential factors of occurrence of security issues are, and on the other hand, it’s also essential to clarify that how pedestrians’ perception of security is influenced. People’s perception is identified to be influenced by external urban environment, therefore the environmental features of urban streets were involved in analysis. This research aims to clarify the effects of built environment and street configuration on pedestrians’ perception of security, by using the technology of electroencephalogram (EEG) to measure the level of psycho-physiological reaction of pedestrians in real-time walking. The correlations between participants’ emotional feelings and environmental features was analyzed, and the gendered and temporal differences of participants’ emotional responses were clarified.

In the parking lots of expressway rest areas, the use of small cars during the daytime on weekends and large cars during the nighttime on weekdays is concentrated, resulting in a difference in the sizes of vehicles that fill up the parking lots depending on the time of day. Considering the limited parking lots space, expressway companies took a measure to convert some of the conventional large-vehicle-only lots to “Flexible Parking Lots”. In the Flexible Parking Lots, two small cars are allowed to park in parallel depending on the congestion in the parking lot, but there are few previous studies that quantitatively show how much it contributes to reducing congestion. Therefore, the purpose of this study is to quantitatively verify how the introduction and installation ratio of Flexible Parking Lots affect the occurrence of vehicles giving up to park and the overall parking lot occupancy rate. The results of the simulation analysis revealed that the number of vehicles leaving the parking area can be reduced by installing Flexible Parking Lots, and that the actual occupancy rate, calculated based on the width of the parking cells, is generally high.

The number of public transportation users is rapidly declining in the regional cities of Hokkaido because of a severe population decline. In response to this problem, the MaaS demonstration tests are being implemented in various regions to improve public transportation services. In this study, we have conducted a macro-transportation simulation for Muroran City, Hokkaido, Japan, using various open data to address the two issues. These objectives include identifying bus routes that need to maintain and areas that need to implement demand-responsive transportation in the future. In addition, in the Hakuchodai district, an “oldnew town” in Muroran City, we analyzed monitor questionnaire data and user movement data from the pilot on-demand transportation project conducted in 2021. Through simulation analysis, we clarified the demanded service level by residents and the number of required vehicles for on-demand transportation.

Japan aims to reduce CO₂ emissions by about 10% in the aviation sector through flight path shortening and other improvements in flight operation methods. However, it has not been quantitatively clarified how much reduction can actually be expected. In addition, considering CO₂ emissions, it is necessary to select the optimal aircraft and number of flights compared to the current situation. Therefore, the purpose of this study was to estimate the CO₂ reduction potential by shortening flight routes and selecting aircraft and flight numbers, and to analyze the effects on passengers and airlines. As a result, the CO₂ reduction potential of shortening flight routes and selecting aircraft and number of flights was quantitatively determined for the domestic airline network. The impact of these reduction measures on passengers and airlines was compared, and it was clarified that high-demand routes have the potential to reduce CO₂ emissions by selecting aircraft and number of flights.

Railway operators are endeavoring to improve levels of their services in order to gain more residents nearby. However, there are no studies focusing on the relationship between levels of railway services and residential location preference in the metropolitan areas. In this study, a questionnaire survey was conducted in the metropolitan areas. We applied conjoint analysis to the collected data, and quantified the effect of each transportation services on residential location preference. We confirmed that the effects can be compared quantitatively among each transportation services. The result of analysis suggests that railway services that affect residential location preference differ depending on resident’s attributes such as where they live and/or how often they use rail.

In this study, we applied the concept of “Social Incentives” from cognitive psychology to examine the effect of presenting normative “information” to bicyclists to improve the utilization rate of bicycle lanes. The control group (n=280), the SI information group (n=280), and the penalty information group (n=280) were presented with six road spaces with different maintenance contents, and the number of lanes. The results showed that presenting SI information could increase the intention to pass on the roadway even under the influence of covariates such as individual attributes, the actual condition of bicycle traffic space in the residential area, and road structure. On the other hand, this tendency was not directly proportional to the rate of roadway passage of others presented by SI.

There are many cases where Diverging Diamond Interchange (DDI) is adopted to prevent traffic accidents relevant to right-turning vehicles at the conventional diamond interchange in Western countries. This paper aims to evaluate the safety of vehicles and pedestrians at DDI based on subject experiments for Japanese drivers and pedestrians by means of a driving simulator and head mount display after virtually reproducing the intersection model in the 3D virtual reality space with reference to the existing intersection shape in Japan. With respect to the driving experiment, compared to the conventional diamond interchange, it is found that DDI has a deceleration effect on vehicles and tends to induce the drivers’ yielding behavior to pedestrians. Additionally, from the perspective of pedestrians, it is revealed that DDI has a superiority in ease of safety confirmation when crossing via analysis of pedestrians’ head motion. Also, the model analysis using the ordered logit model and structural equation model indicates that rearrangement of sidewalk design will lead to creating positive awareness of pedestrians.

In winter Hokkaido, poor visibility occurs due to snowstorm on the road and increases the risk of accidents and traffic restrictions. Visibility conditions on the road are affected by snowfall, wind, and roadside environments, it is desirable using not only still image captured by Closed-circuit TeleVision (CCTV) camera but also snowfall information along the road. In this study, we attempted to verify the applicability of precipitation intensity observed by eXtended RAdar Information Network (XRAIN) as snowfall information along the road. Using cross-correlation, we investigated degree of influence of precipitation intensity of XRAIN on value of the WIPS calculated from still image captured by CCTV camera. As a result, when snowfall was observed and wind direction was west, the time variation of precipitation intensity by XRAIN affected that of value of the WIPS, and it was revealed that the change of value of the WIPS was related to that of precipitation intensity with time lag. It was indicated that using precipitation intensity observed by XRAIN as snowfall information was usefulness. On the other hand, it was also revealed that information such as wind speed, wind direction, roadside environment, and so on is necessary when the time change between precipitation intensity and value of the WIPS was different.

In recent years, the logistics industry in Japan has been facing a serious problem of labor shortage due to the decrease in the working population caused by the declining birthrate and aging population. In order to maintain and develop a stable logistics network in the future, it is necessary to improve labor productivity through the introduction of new technologies. The introduction of various new technologies in the logistics industry is currently under consideration, and one of the most notable is novel high capacity mobility such as double trailer truck and truck platooning. However, it entails vehicles/sets of vehicles which are extremely long and are considered to have a high accident risk. Especially, highway merging points is bottleneck for introducing such high-capacity mobility due to a high potential for accidents. In this research, a simulation model was developed using reinforcement learning to quantitatively and comprehensively analyze the impact of introducing double trailer trucks and truck platooning on the safety of highway merging areas.

The traffic volume varies by time of a day. For example, traffic volume of an expressway between cities has two typical peaks for the morning rush hour and evening rush hour. The fluctuation of drivers can be analyzed by estimating a probability density function from traffic volume data that is easy to observe. In this case, it is necessary to process the periodic data such as traffic volume in a day by applying directional statistics. In this study, we estimate the parameter for the mixture of circular distribution, which is the probability density function for angular data. Finally, the two peaks of morning rush peak and evening rush peak are divided. It is clarified that the earlier peak is sharp and left skewed peak, and the latter peak is gentle peak for both passing and driving lanes.

The average step speed of the escalator is 30m per min. But some escalators have more step speed to promote traffic capacity. In previous studies, it was found that the walking rate of the high-speed escalator is less than the normal speed one. However, the quantitative research had been missing. In this study, behaviors of passengers on normal speed escalator (V=30m/min) and high-speed escalator (V=40m/min) were video recorded and analyzed at TOYOSU station in Tokyo Metro Line. As a result, the linear relationship between traffic volume and walking rate was found at both type of escalator. And the high-speed escalator can decrease the walking rate by 5 - 8 points. As walking speed on the escalator, the high-speed escalator can decrease walking speed by 9%. Therefore, the effect of the high-speed escalator on walking rate / speed reduction is relatively small.

Previous studies have shown that the traffic performance of interurban expressways declined during the past 14 years from 2003 to 2016. However, it is not clear how it decreased during the same period. In addition, there are few studies showing the secular change of the observed non-congested speed by traffic volume, and the change in speed distribution is unknown. In this study, after analyzing the non-congested speed by traffic volume on interurban expressways for 24 years from 1996 to 2019, it was clarified that it started to decrease from 2001 to 2008, and the free flow speed distribution shifted to a lower region. In addition, the speed reduction is large for constrained flow at high flow condition, and the speed decreased more over time especially for large vehicles.

In the estimation of traffic capacity at stop-controlled intersections in Japan, overseas parameter values are used due to the lack of studies in Japan. However, the usage of overseas values may lead to overestimation and underestimation of traffic capacity in Japan because these traffic environments may be different. In this study, using the parameter values at the stop-controlled intersection obtained from the observation survey in Japan, various comparative analysis was conducted. As a result, it was clarified that the parameter values at the stop-controlled intersection in Japan are influenced by the angle of the intersection, the type of vehicle, the time of day, and so on. Furthermore, it was shown that the measured traffic capacity can be reproduced by the parameter values obtained in this study.

In the past, the police have conducted traffic enforcement activities as a countermeasure against traffic accidents, and have achieved a certain degree of success. However, the relationship between traffic accidents and traffic enforcement activities is still unclear, and traffic enforcement activities based on clear evidence have not yet been implemented. In this context, there is a movement toward the use of artificial intelligence to predict the occurrence of traffic accidents and to implement traffic effective enforcement activities. In this study, we developed an accident prediction model that takes into account traffic enforcement activities, and evaluated the relationship between traffic accidents and traffic enforcement activities. In addition, we developed a model to estimate effective methods of traffic enforcement activities using Deep Q-Network, a type of artificial intelligence. As a result, we were able to quantitatively understand the deterrent effect of traffic enforcement activities on traffic accidents, and we were able to specifically propose appropriate traffic enforcement activity methods according to traffic conditions.

An auxiliary lane is usually used as an effective measure against traffic congestion to correct lane utilization and increase traffic capacity at the sags of multi-lane expressways. There are three forms of auxiliary lanes that have been installed in Japan, i.e. left-addition left-closure, right-addition right-closure, and right-addition left-closure. The objective of the study is to obtain guidelines for the most appropriate operational form of an auxiliary lane at both high and medium traffic levels. In this study, the traffic behavior is first obtained for each type of auxiliary lane from the video surveys to calibrate an existing microscopic traffic flow simulation model. Then the simulation model is used to examine the applicable conditions for the installation of an auxiliary lane in different road and traffic conditions at the two traffic levels from the viewpoint of traffic efficiency and safety. As a result, the right-addition left-closure type is suitable as a countermeasure against traffic congestion when traffic volume level is high. When the traffic level is moderate, however, it is optimal to apply the right-addition right-closure type to improve the level of service of the traffic flow.

This study analyzed the effectiveness and user acceptability of a narrow two-stage crossing facility based on a video observation survey and questionnaire survey at a two-stage crosswalk with a traffic island of 2.0 meter width installed on two-lane, two way road in Meito Ward, Nagoya City. As a result, it was found that the narrow two-stage crossing facility was effective in facilitating and safe crossing, such as increasing the vehicle yield rate and reducing vehicle speed, and that the effect was sufficient in comparison with other locations with similar road structures. In addition, it was found that pedestrians generally accepted the width of the traffic island of approximately 2.0 m, that the presence of the traffic island increased drivers’ attention to pedestrians, and that visibility of the traffic island was one of the factors that strongly influenced users’ decision before and after the installation of the traffic island by statistical test and discriminant analysis.

This paper investigates the impact of work from home (WFH) on the temporal agglomeration (dis-) economies associated with the morning commute in cities. Specifically, we extend the equilibrium model by Takayama¹⁾ to a model including the effects of WFH, and analyze its equilibrium and social optimum both theoretically and numerically. We then show that (i) WFH would make work start times to be more clustered (inconsistent with staggered work hours); (ii) for the situation where the productivity of individual firms and workers improves due to the introduction of WFH, the social welfare can be lower than before.

This study develops a queueing model based on a continuum traffic flow model that endogenously describes the capacity drop (CD) phenomenon at freeway sag and tunnel bottlenecks and analyzes the characteristics of the traffic breakdown probability. The model describes the traffic breakdown probability in two steps, distinguishing between fluctuations in arrival demand and those in traffic capacity, in addition to taking into account the CD phenomenon. Monte Carlo simulations are performed for each step, and the following results are obtained: (i) the CD phenomenon shifts the traffic breakdown probability distribution to a lower demand range; (ii) the traffic capacity fluctuations mainly determine the shape of the breakdown probability distribution.

In this study, the impact of introducing time-varying fare during rush hour was analyzed by simulation, assuming structural changes in the demand for commuter rail in urban areas in the post-COVID-19. In the simulation, a departure time choice and passenger demand equilibrium assignment Model for commuters with two different commuting styles and a system optimal assignment Model for deriving the first best pricing were constructed. Simulation results under three post-COVID-19 scenarios ((1) increase in telework, (2) increase in flexible work hour, and (3) increase in resistance to congestion) confirmed that the total fare revenue for charges obtained by congestion rates and time-varying fare changed from before COVID-19. The Model was applied to a real line (Seibu Shinjuku Line) to indicate possible future changes in commuters’ departure time choice behavior.

The objective of this study is to analyze the change in cognition and understanding about “Traffic accident risk” and the behavioral intensions change for safe driving by providing the driver with traffic accident risk information. In this study, in order to grasp changes of cognition and understanding about the concept of “Traffic accident risk” and the applicability of traffic accident risk information, multiple communication experiments about traffic accident risk information were conducted. After analyzing changes in cognition and behavioral intentions regarding traffic accident risk information in each experiment, long-term changes in cognition and behavioral intentions regarding traffic accident risk information were shown by comparing results of two experiments. In addition to that, the route choice experiment providing traffic risk information were conducted before and after provision communication information regarding traffic accident risk and the effects of communication on low accident risk route choice behavior were analyzed. It was found that subjects of experiments who correctly perceived “the relationship of the traffic accident risk between roads and highways” increased by communication and subjects who want to use the low accident risk route increased either. As shown results of route choice model providing traffic accident risk information, communications about traffic accident risk information provision affected low accident risk route choice behavior positively.

Community transport provided by residents plays key role as a complimenting of public transport in a rural area. In the previous study, actual state of the community transport was found by the questionnaire surveys. However, the questionnaire surveys do not fully cover the continuity perspective. Therefore, the aim of this study is to investigate the continuity of community transport based on the questionnaire survey. Our survey targets the community transport defined by road traffic act in Japan. Continuity was measured by subjective continuity confidence. Decision tree analysis revealed that the design of transportation services is strongly related to short- and medium-term continuity, and that long-term continuity is strongly related to key-person independence.

This study analyzes two car-following models based on the Intelligent Driver Model+ (IDM+) for developing an endogenous and easy-to-use microsimulation model that can represent the capacity drop (CD) phenomenon in freeway sag sections. One is a model in which the safety time gap varies depending on the location, suggested by the recent CD theory, and the other is a conventional model in which a gradient term is directly added to the original model. Specifically, we verify whether or not the CD phenomenon occurs for these models by conducting simulation experiments in which the model parameters are varied systematically. We then show that both models can reproduce the CD phenomenon if the parameters are appropriately chosen.