Actual Electricity Utility Factor of Plug-In Hybrid Electric Vehicles in Typical Chinese Cities Considering Charging Pattern Heterogeneity

The actual energy saving effect of plug-in hybrid vehicles (PHEVs) is usually evaluated by the electricity utility factor (UF) in a standardized charging pattern. To further evaluate the impacts of the charging pattern heterogeneity of PHEV, actual vehicle travel data are adopted to classify the charging pattern in seven typical Chinese cities and derive its impacts on actual UF. Additionally, UF curves are fitted as power exponential functions. The result shows that during daily usage, UF can reach over 0.8 for 50 km all-electric-range PHEVs for the 77% frequently charging adopters, while it is as low as 0.1 for the 3% rarely charging adopters. Comprehensive UF values at an actual charging pattern are 0.53 and 0.68 for the 50 km and 80 km all-electric-range PHEVs, and the values are 0.03 and 0.04 smaller than the standard UF, respectively.

Influence of Sea Sand on Sintering of V–Ti–Fe Concentrate—A Case Study from Indonesia

This study explores the feasibility of Indonesian sea sand in replacing V–Ti–Fe concentrate for sintering. The influence of different additive proportions of Indonesian sea sand on sintering index and sinter properties is examined in a laboratory by adjusting the substitution proportion from 5% to 40%. Results imply that vertical sintering speed and utility factor show an apparent decreasing trend, but drum strength, finished product rate and returned fine rate are not significantly affected with the increase in the proportion of Indonesian sea sand and with the decrease in the proportion of V–Ti–Fe concentrate. With the increase in the proportion of sea sand, the reduction degradation index of sinter at low temperatures declines sharply from 65% to 31%, the grade of sinter and content of TiO2 changes slightly, and the reduction degradation and degree decline. Unlike V–Ti–Fe concentrate, Indonesian sea sand does not perform well in sintering, and the substitution proportion should not exceed 35%.

A Decision-making method for the Application of Pavement Repair Materials Based on Stackelberg Model

Highway repair cost mainly depends on the toll income, which in turn is associated with the traffic volume. Scientifically making decision for the application of repair materials is within the reasonable planning of managers regarding road maintenance scale and funds. For exploring effective strategy specific to the highway maintenance plan, the paper focuses on integrating the utility factor of traveler into the highway repair decision. Relevant problems are introduced, together with the establishment of the Stackelberg model. Considering the sensitivity analysis, the heuristic algorithm is employed specific to the traffic volume N. The paper solves the decision-making model with regard to the two expressways’ maintenance plan, as well as derives corresponding strategies. At last, the paper concludes, based on analyses, the general process regarding the maintenance decisions of multiple highways with the traffic volume N, assisting highway operators in making effective decisions.

ANALISIS PRODUKTIVITAS TENAGA KERJA PADA PEKERJAAN PASANGAN BATA PERUMAHAN TIPE 36 (Studi Kasus pada Perumahan Griya Putri Tanjung Kota Bengkulu)

The process of housing development is inseparable from labor productivity. This study aimed to determine the value of LUR (Labor Utilization Rate), workgroup productivity, and dominant factors that influence the masonry work in Griya Putri Tanjung Housing. The method used in the research was field observations for six houses by observing the effective work time, contribution work time, and ineffective work time, calculating the area of bricklaying and questionnaires to 12 workers. The questionnaires were processed with SPSS 24. The results obtained showed that the highest worker utility factor (LUR) was on day 2 of 88.89%. The Average LUR in Putri Tanjung Griya Housing is greater than 50%, so the work utility factor reaches the effective time. The highest average productivity of each workforce is on the 3rd day by a productivity value of 1.51 m2/hour/person. The most dominant factor was the time factor and implementation conditions (up to 82%), then the physical factor of labor (32,8%), managerial (-24,1%), the background of the employee (19,1%). The lowest factor was the group factor and the expertise of the workforce by a percentage of influence of -17,5%. Keywords: housing, labor, bricklaying.

Stackelberg game analysis of enterprise operation improvement decision and consumer choice behaviour

: In the process of enterprise operation and management, operators constantly improve the operating environment according to the changes of the market, so as to repair and update the project content to attract consumers. Consumers choose projects based on the content and their own needs or preferences. The operator's improvement and renewal of the project and the consumer's choice of the project form a game relationship. In order to explore the effective improvement of operation decision, we integrate consumers into operation decision as a utility factor. Under the assumption of maximizing the benefits of consumers and managers, we describe the related problems and establish a Stackelberg game model. We use the heuristic algorithm of sensitivity to solve and calculate the operation decision model of two projects with N number of consumers, obtain the corresponding strategy and carry out discussion, so as to provide decision-making reference for the operation enterprise of two charging projects.

Influence of User Preferences on the Revealed Utility Factor of Plug-In Hybrid Electric Vehicles

Plug-in hybrid electric vehicles (PHEVs) are an effective intermediate vehicle technology option in the long-term transition pathway towards light-duty vehicle electrification. Their net environmental impact is evaluated using the performance metric Utility Factor (UF), which quantifies the fraction of vehicle miles traveled (VMT) on electricity. There are concerns about the gap between Environmental Protection Agency (EPA) sticker label and real-world UF due to the inability of test cycles to represent actual driving conditions and assumptions about their driving and charging differing from their actual usage patterns. Using multi-year longitudinal data from 153 PHEVs (11–53 miles all-electric range) in California, this paper systematically evaluates how observed driving and charging, energy consumption, and UF differs from sticker label expectations. Principal Components Analysis and regression model results indicated that UF of short-range PHEVs (less than 20-mile range) was lower than label expectations mainly due to higher annual VMT and high-speed driving. Long-distance travel and high-speed driving were the major reasons for the lower UF of longer-range PHEVs (at least 35-mile range) compared to label values. Enhancing charging infrastructure access at both home and away locations, and increasing the frequency of home charging, improves the UF of short-range and longer-range PHEVs respectively.