Greenberg's Model Research Articles

ANALISIS PERBANDINGAN NILAI DERAJAT KEJENUHAN MENGGUNAKAN MODEL GREENSHIELD, GREENBERG DAN UNDERWOOD TERHADAP MKJI 1997 PADA JALAN PERKOTAAN TIPE 2/2 UD (STUDI KASUS RUAS JALAN SALEH SUNGKAR AMPENAN KOTA MATARAM)

If the population increases and the total traffic flow also increases without being matched by an adequate increase and improvement of road infrastructure, it will result in an increase in the degree of saturation which is a parameter in determining the performance of a road section. One of the roads affected by the population growth is the Saleh Sungkar road which is an urban road type 2/2 UD. The Greenshield, Greenberg and Underwood models are the 3 models used to determine the relationship between volume (flow), speed (speed) and density (density). The relationship between flow, speed and density is used to determine or determine the mathematical value of the capacity of a road section and the degree of saturation. This study aims to determine the comparison of the degree of saturation of Jalan Saleh Sungkar which is an urban road using the Greenshield, Greenberg and Underwood models against MKJI 1997. From the results of the analysis, it was obtained that the degree of saturation using the Indonesian Road Capacity Manual (MKJI 1997) was 0.53, so Jalan Saleh Sungkar was at the level of sevice "C" (stable flow, but the speed and motion of the vehicle were controlled, the driver was limited in choosing the speed). Meanwhile, the degree of saturation based on the Greenshield model is 0.55, the Greenberg model is 0.72 and the Underwoods model is 0.60. Both MKJI 1997 and the three models are still at level of service "C".

Implementation of A.I. Vehicle Detection for Traffic Analysis Using In-situ Surveillance Infrastructure

Traffic flow parameters are required for optimizing traffic operations, design of pavements, and future planning of traffic networks. Unfortunately, due to the unique characteristics and variety of vehicles in the sub-continent i.e., size and design, the accuracy of results for a vision-based system is challenged, since most thorough datasets are based on European and American traffic. This paper proposes a solution by developing a detection model ground-up using a dataset created from the local traffic surveillance footage, and creating a python pipeline for vehicle speed detection and classification. The vehicle classification model is developed using the state-of-the-art YOLO object detector which significantly reduces the computation time required to maintain the efficiency of the proposed solution. Furthermore, a computer-vision script is developed to track the movement of vehicles in the footage and record the speeds in a spreadsheet. The technique used eliminates the video calibration, including distance and angle, required for detecting accurate speeds. Finally, the realtime traffic data is analyzed to derive the fundamental traffic flow parameters and discuss the relation between flow and density. To ascertain the validity of this survey technique, the results are compared to the following renowned traffic flow models: The Modified Greenberg model, Eddie’s model, and The Two-regime model. The results are found to closely follow the models in all three cases.

Research on travel time prediction of expressway in peak period based on Greenberg model

Expressway travel time is an important parameter to describe the traffic status, which can accurately reflect the efficiency of expressway traffic. To further simplify the complexity of the travel time prediction method, and improve the prediction accuracy, in this paper, the travel time prediction of the expressway is divided into three cases for discussion. First of all, based on the Greenberg model, under the premise of a comprehensive analysis of the section flow, traffic density, and other factors, to establish different sections under the peak period expressway vehicle travel time prediction model. Finally, the model is verified by taking the expressway around the city as an example. The results shows that the prediction results are always within 10% of the actual measurement error, which shows that compared with the measured data, the error of the model proposed is small, the prediction accuracy is high, within the acceptable range.

Research on travel time prediction of expressway in peak period based on Greenberg model

Research on travel time prediction of expressway in peak period based on Greenberg model

ROAD PERFORMANCE ANALYSIS WITH MEDIAN AND WITHOUT MEDIAN ON THE ROAD OF A.YANI SATUI

The road that is located in the City of Satui is a road that connects cities that are large in the South Kalimantan, the road is often used by mining trucks. From these conditions, there will be a high movement of people, goods, and services. For this reason, it is necessary to conduct a review to determine the performance of the road.The location in this study is on A.Yani Street, City of Satui, South Kalimantan. On this road, there is a part of the road that has a median and does not have a median. Data collected from the results of traffic surveys are primary data which includes geometric data, traffic volume data, and traffic speed data. Secondary data which includes an overview of the study area. The data obtained are then grouped according to the composition of the vehicle. Then the data is made into hourly traffic data to get volume, speed, and density. The data obtained was analyzed to obtain capacity, the appropriate relationship model, and performance changes between roads.The results of data analysis on A.Yani Street, City of Satui are the maximum volumes obtained on the road with a median of 468,75 amp/hour while those on the road without the median are 421,51 amp/hour. The maximum density obtained on the road with a median of 133,67 SMP/km while on the road without a median of 55,86 SMP/km. The maximum speed obtained on the road without the median is 129,2 km/hour while the road with the median maximum speed is 60,87 km/hour. The corresponding equation for A.Yani Street, the City of Satui on the road with the median is the Underwood model, y = 61,161e-0,048x with the R-value of 0,90675 while the road without the median is the Greenberg model, y = -20,41ln(x) + 82,208 with an R-value of 0,90161.

Mathematical Model of Traffic Speed and Capacity in the Archipelago Base

The transportation engineering developing who the application of the principal use planning, analysis and design to the disciplines comprising transportation: its vehicles, physical infrastructure, safety in travel, environment impacts and energy usage. The mathematical model in base archipelago was not much enough to research by transportation practiced. It had been of characteristic which different mainland. This paper using greenshields and greenberg models for approach real condition of the base archipelago. In the transportation involves working with the businessman, with industry, with citizen group, with elected officials, and with employes to the joint each segment of the public strip depended on at least one constructed facility. In this time there three components that included the discussion of the traffic of a microscop scale were flow, density and speed. At the greenshields model, the speed-density relationship show whose the value of speed higher than value of density lower with determination value 0,9755 where the curve of flow-density relationship show the value determination 0,8634 and for curva of flow-speed relationship showing whose maximum value of flow 1807 vehicles/hour at the value traffic speed 46 km/hour, traffic speed which at the lower or it the higher, so it condition given impact that the value of flow will going to low. on the other hand for greenberg model at speed-density relationship’s determination 0,9463, density-flow relationship show that the value minimum of density is 25 vehicles/km while value of flow is 1400 vehicles/hour and the relationship between flow-speed curve show that value maximum flow 1750 vehicles/hour with value speed 37. Base the value of each condition, so the greenshields model was better than greenberg model for this research. The mathematical model of the traffic flow which approach the real condition for the base archipelago was greenshields model.

The Viscosity Effect on Velocity of a Macroscopic Vehicular Traffic Model

Traffic in Mexico City poses a serious problem of vehicle saturation that causes a decrease in speed and increased transport time in the streets that suffer mobility collapses. A macroscopic model of vehicular traffic is used to show the effect of viscosity on the vehicular variables (speed and vehicle density), applied to two avenues in Mexico City, is studied. The input parameters were calculated following the Greenberg model. As the original model presents numerical divergences, the two assumptions corresponding to conservation of the vehicle’s mass and the viscous term are modified. The results suggest that the viscosity depends on time and that it can be adapted to recommend modifications in urban mobility parameters, or even to implement the public planning policies in construction of infrastructure for urban transport, to make vehicle flow more efficient.

Traffic noise level handling on A P Pettarani road towards elevated toll road construction

The construction of the elevated toll road is part of the transportation network system, in addition to managing the traffic system in the area to be more integrated, the facility is also used to deal with congestion that often occurs, as well as the construction plan of elevated toll on Pettarani road is expected to reduce the level of congestion that occurs. Based on previous studies, the prediction of noise levels on AP. Pettarani roads when the elevated toll road is operating with a shift estimated of 25% of the vehicle’s volume to the elevated toll road at 79.58 dB. Therefore, we need a way to handle the noise level on the AP Pettarani road if the elevated toll road is operating. Traffic load analysis is performed using the V-S-D (volume, speed and density) model analysis. The V-S-D model analysis consists of 3 models namely the Greenshield Model, the Greenberg Model, and the Underwood Model. The results of the V-S-D model analysis obtained are the Underwood Model at each point of the scenario so that it is used to calculate the average speed on the road segment according to the traffic volume. Then the results of the analysis and statistical tests through several variations of the simulation have obtained the best noise level handling by using traffic loading on the AP Pettarani Road through 50% motorcycle switch to the BRT (Bus Rapid Transyt) and can reduce the noise level by 3.05 dB.

HUBUNGAN VOLUME, KECEPATAN DAN KEPADATAN DENGAN MODEL GREENSHIELDS, GREENBERG, DAN UNDERWOOD PADA RUAS JALAN LUAR KOTA KAWASAN GUNUNG GEURUTEE

In Indonesia, Karl-L Bang research in 1994 on the relationship between traffic parameters was included in the Indonesian Road Capacity Manual 1997. The research has undergone many changes between 1994 and 2018 in the growth of traffic that may affect traffic flow and volume, speed and density all urban roads, roads outside the city in an area, In Aceh studies have also been conducted into the relationship between traffic parameters on different roads. On this basis, it is very necessary to know the characteristics of traffic flows that occur on the Banda Aceh - Meulaboh section 65+450 is located in Aceh Jaya Regency, in the province of Aceh. Given that this road is located in an extremely mountainous area, where there are many very steep curves and ravines and rocks on the cliff side of the road. Analysis using models Greenshields, Greenberg, and Underwood. The results of the study show that the Greenshields model is the most satisfying compared to the Greenberg model and the Underwood model with a coefficient of determination (R2) greater than 0.88. The model is by the traffic conditions on the Outer City Road. Then the traffic flow obtained can not reach optimum conditions, namely in a stable traffic flow condition. The relationship between speed and density (S-D) with the model equation is S = 36,525 - 0,815 D; The volume-density (V-D) relationship with the model equation is V = 36,525 D - 0,815 D2; The relationship of volume - speed (V-S) with the model equation is V = 44,835 S - 1,228 S2

PENGARUH MANUVER KENDARAAN PARKIR DI BADAN JALAN TERHADAP DERAJAT KEJENUHAN PADA JALAN TEUKU UMAR KOTA BANDA ACEH

Teuku Umar Street has very high activities as an access service, but there are also on-street parking facilities. On-street parking facilities cause traffic congestion on teuku umar road area, especially in public service areas such as Seutui Market, Harapan Bunda Hospital, Suzuya Mall and Canai Mamak. This is caused by the influence of vehicle maneuvers when entering and exiting from parking facility location, and this phenomenon often occurs during rush hour and the volume of vehicles is very dense. Based on these problems, a study was conducted to determine the effect of vehicle maneuvers when exiting and entering of parking facility on the traffic of degree of saturation and relation model between volume, speed and density using 3 models i.e. Greenshields, Greenberg and Underwood. Based on the analysis results, the Greenberg Model is the best model with the highest determination of the three variables of speed-density-volume. The model is chosen based on the greatest value of determination approaching one rate. The capacity of Teuku Umar Street Directions Gunongan-Sp.Tiga is 2970 pcu/hour, and after the on-street parking activity, the capacity decreased by 2079 pcu/hour (30%). For the way to Gunongan, the capacity is 2970 pcu/hour, after parking activities the capacity drops 2524 pcu/hour (15%). The value of saturation degree in the segment is no parking facility towards Gunongan to Sp. Tiga is 0.31 and there is parking obtained 0.43. Sp. Tiga-Gunongan street direction has the value of surfeit level on the segment no parking facility at 0.37 and there is parking obtained at 0.44. The alternative improvements to increase capacity is by providing special parking facilities and limiting vehicles in and out, so that the surfeit level will decrease.

Optimization of Traffic Flow On KS Tubun Street using Greenberg Model

KS Tubun Street is a street in Bogor, which has a fairly high vehicle volume and become one of a high-traffic jam area. This is caused by KS Tubun Street is the main road for road users from Jakarta and Bogor. Traffic jam problem that occurs due to the confluence interchange of traffic flow and traffic lights settings that are not proportional to the volume of vehicles across the road. Optimization of traffic flow at KS Tubun Street performed by the stages of forming a model of traffic flow, determining the density and velocity of the vehicle is based on the Greenberg model, and determining the length of the traffic lights to avoid a buildup of vehicles. The result is a traffic flow model with distance and time parameters. The density of vehicles that occurs on the streets of KS. Tubun street based on the Greenberg model between 180 to 240 unit car of passanger (ucp) with the average velocity of vehicles 15 to 19.5 km per hour. The density of vehicles on KS. Tubun street can be break down by increasing time. Traffic light cycle time can be reduced for 8 seconds with the red light glowing time is 80 seconds and the green light glowing time is 62 seconds.

Impact Analysis of Rainfall on Traffic Flow Characteristics in Beijing

To improve traffic operations and management under inclement weather, this work quantificationally investigated the influence of rainfall on the traffic flow characteristics of urban expressways in Beijing. Four basic traffic flow models (Greenshields model, Greenberg model, Underwood model, and Drake function model) were compared to determine the most suitable model for the detected data, which were collected by microwave detectors in the Beijing 2nd and 4thring expressway under normal or rainfall condition. Results showed that the Greenshields model was the best-fitted model. Under rainfall conditions, varying degrees of reductions were observed in the road capacity, free-flow speed, and speed at capacity. The findings also showed that the reductions of road capacity were 7.26%, 10.87%, and 17.09%, and the reductions of free-flow speed were 3.07%, 5.29%, and 6.64% under light rain, medium rain, and heavy rain, respectively. The reductions of speed at capacity revealed a similar tendency as that of the free-flow speed. Simultaneously, a new model that incorporated rainfall intensity is proposed on the basis of the Greenshields model and can achieve good performance. Overall, the results are beneficial for traffic managers in improving their decision s and predictions under rainfall weather.

Pemodelan Hubungan Parameter Karakteristik Lalu Lintas pada Jalan Tol Belmera

Belmera toll road in North Sumatra was the first toll road, links Belawan-Medan-Tanjung Morawa. The aim of this research is to find the relationship model between speed, density and volume on Belmera toll road based on a traffic study. The traffic study which embodies volume study and the speed of vehicles were divided into 5 vehicle classification, into 2 traffic lines (Entrance and Exit Tanjung Morawa’s toll gates), was conducted on Friday and Saturday around the peak hour on each traffic current. The study concluded that Greenberg model is the best approach for traffic current on Belmera toll road. According to Greenberg model we acquire a mathematical equation of the relationship between speed-density, volume-density, and volume-speed of Exit Tanjung Morawa’s toll gates as: S=98,100-6,700LnD, V=98,100D–16,700DLnD, V=355,758Se-0,059S and the Entrance as: S=99,312–17,442LnD, V=99,312D–17,442DLnD, V=297,033 Se-0,057S. Based on the observation and application of Greenberg model, traffic indicator (v/c, flow, density) of both current revealed that the level of service of Belmera toll road is C and it’s a fine traffic performance so far. The speed rate (km/hour) and density (pcu/km) revealed that the acquired rate from the observation is smaller than the application of Greenberg model.

Formation of amino acid precursors with large molecular weight in dense clouds and their relevance to origins of bio-homochirality

AbstractA wide variety of organic compounds have been found in carbonaceous chondrites and comets, which suggests that extraterrestrial organic compounds could have been an important source of the first terrestrial biosphere. In the Greenberg model, these organic compounds in the small bodies were originally formed in interstellar dusts (ISD) in dense clouds by the action of cosmic rays and ultraviolet light. We irradiated a frozen mixture of methanol, ammonia and water with high-energy heavy ions from an accelerator (“HIMAC” in NIRS, Japan) to simulate the action of cosmic rays in dense clouds. Racemic mixtures of amino acids were detected after hydrolysis of the irradiation products. A mixture of carbon monoxide, ammonia and water also gave such complex amino acid precursors with large molecular weights. When such amino acid precursors were irradiated with circular polarized UV light from a synchrotron, enantiomeric excesses were detected. The yield of amino acids was not largely changed between, before, and after CPL-irradiation. The present results suggest that the seed of homochirality of terrestrial amino acids were originally formed in interstellar space.

Development of Improved and Efficient Traffic Flow Model

The paper deals with development of efficient and improved traffic flow model to predict the space mean speed, ūs, in terms of the mean free flow speed, uf, and the density, k. The Greenberg model (which is based on fluid-flow analogy concept)satisfies the boundary condition only at jam density, kj. It violates the boundary condition at zero density, k, in the sense that it can only be attained at infinitely high speeds according to Khisty and Lall [1] and Papacostas and Prevedouros [2]. The intent of this research work is specifically to arrive at an improved version of Greenberg model (CSUF model). The CSUF model will be accomplished by expansion of natural log expression in Greenberg expression and considering only linear terms. The correlation coefficient will then be calculated. Existing experimental results will be used to validate the model. These results will then be compared with the results already existing in the literature from the Greenberg model as well as the Underwood and Eddie model.

Modifications to Warner's Model Using Blank Cards

SYNOPTIC ABSTRACTIn recent years, several authors have suggested modifications of the Warner's (1965) randomized response model and of the Greenberg, Abul-ela, Simmons and Horvitz (1969) unrelated question model by using some blank cards in the randomization deck and by asking respondents to simply say “yes” (or “no”) if a blank card is drawn. In this paper, we examine the effectiveness of these modifications.

The alpha spending function approach to interim data analyses.

Over the past three decades, clinical trials have become one of the major standards for evaluating new therapies and interventions in medicine [1–3]. Numerous clinical trials have been conducted during this period across a wide variety of diseases, evaluating drugs, procedures, devices, and biologic materials. The fundamentals of the design, conduct, and analyses of clinical trials have been developed and refined during this period as well. One such fundamental is that clinical data should be carefully monitored during the course of the trial so that unexpected or unacceptable toxicity can be detected as soon as possible in order to minimize patient exposure; in addition, trials should not be continued longer than necessary to prove the benefits of the therapy or intervention under study, or to understand the trade-offs between the benefits and risks of the therapy. In order to accomplish this goal, the National Institutes of Health sponsored a committee in the 1960s to develop guidelines for the conduct of clinical trials. The chair of this committee was Dr. Bernard Greenberg from the University of North Carolina, and the report, which was issued in 1967, has become known as the Greenberg Report [4], although it was only recently published in the literature. This report endorses the concept of interim review of data by an independent Data and Safety Monitoring Board (DSMB), a committee that has no conflict of interest for the study. This typically means that committee members should not be investigators entering patients into the trial. The Coronary Drug Project (CDP) [5] was one of the first trials to implement the Greenberg model.

Greenberg's Two-Factor Safety and Effectance Drive Theory: Implications for Rehabilitation

Greenberg proposed a model of drive theory which focuses on safety and effectance as primary motives for human behavior. In this paper, we elucidate Greenberg's theory, and apply it to persons with disabilities within a rehabilitation context. This model can add a great deal of specificity to understanding the conflicts people with disabilities may experience in their attempts at life adjustment. We utilize several case examples to illustrate that Greenberg's model is a useful tool to conceptualize and deal with client adjustment issues.