bluuebunny/crossref_metadata_2025 huggingface dataset:
Benefit-Cost Analysis of Weather Information for Winter Maintenance
Authors: Strong Christopher , Shi Xianming
Published: November 2008

Surface transportation in the United States is continuously affected by adverse weather conditions, which contribute to thousands of highway fatalities and billions of dollars in economic loss every year. Winter weather has its own peculiar challenges, to which transportation agencies respond through winter maintenance operations. Recent trends toward proactive winter maintenance operations have placed a premium on the value of timely and accurate weather information that reflects current and forecast conditions in the roadway environment. However, few studies have sought to quantify this value and compare it to the costs of obtaining such customized weather information. The Utah Department of Transportation (DOT) implemented a weather operations program that assists the agency's operations, maintenance, and construction functions by providing detailed, often customized, area-specific weather forecasts. This program's genesis provides a useful case study to quantify the cost-effectiveness of weather information. Described is the application of an artificial neural network model using winter maintenance cost data from dozens of Utah DOT maintenance sheds for the 2004 to 2005 winter to estimate the cost-effectiveness of this program. The model estimated the value and additional saving potential of the Utah DOT weather service to be 11% to 25% and 4% to 10% of the Utah DOT labor and materials cost for winter maintenance, respectively. On the basis of the program's cost, the benefit-cost ratio was calculated at over 11:1. The results highlight the potential benefits that may be realized by an agency using improved weather information to direct its winter maintenance activities.
Red Retroreflective Raised Pavement Markings
Authors: Miles Jeffrey D. , Carlson Paul J. , Ullman Brooke , Trout Nada
Published: November 2008

Research was conducted to evaluate drivers’ understanding of red retroreflective raised pavement markers (RRPMs) on two-lane and four-lane undivided and divided roadways. The study included 191 participants, equally divided between three participant groups: drivers from countries with left-hand drive (e.g., Australia, United Kingdom, and Japan), drivers from Hawaii, and drivers from the continental United States. Five typical roadway configurations were tested by means of a laptop survey. For each roadway configuration, standard pavement markings were shown as a baseline condition. Three alternate marking treatments were shown for each typical roadway configuration. Two of the alternative marking treatments consisted of different combinations of supplemental RRPMs, and the third alternative treatment consisted of supplemental pavement marking arrows without RRPMs. The general findings were that red RRPMs on one-way divided roadways to indicate the wrong direction of travel helped drivers realize when they were going in the wrong direction; red RRPMs on undivided roadways can improve understanding of drivers from countries with left-hand drive without reducing the understanding of drivers from Hawaii and the continental United States; and replacing supplemental RRPMs with supplemental arrows always improved the rates of correct responses for all roadway configurations and for all participant groups.
Modern Pavement Marking Systems
Authors: Burns David M. , Hedblom Thomas P. , Miller Terry W.
Published: November 2008

Road marking systems have retroreflective properties to assure adequate nighttime visibility. Modern systems can also provide night visibility under rain and wet conditions. The FHWA is currently working to establish requirements for minimum maintained retroreflectivity of pavement markings on all U.S. roads. Its task is complicated by the fact that conventional dry retroreflectivity measurements do not tell the entire story about pavement marking visibility at night. To that end, there is ongoing research into the relationship between a pavement marking system's retroreflective properties and the level of on-road visibility the system provides. A pavement marking system is composed of three basic components: the optics, the structure, and the binder. Each component influences the retroreflective efficiency of the marking, its visibility at night, and the reliability of predictive correlations between the two. Such correlations are required to set practicable minimum maintained pavement marking visibility levels. A Comité Européen de Normalisation 30-m coefficient of retroreflected luminance (RL) value is commonly assumed to be a good predictor of the on-road visibility of pavement marking. While useful for quality assurance, this standardized RL value is not a measure of visibility. This paper describes choices for pavement marking components and their impact on night visibility. Data on the fundamental relationship between optics and retroreflective efficiency related to road marking visibility are presented. Dry and wet conditions are considered, as are flat and structured markings. Field measurements of pavement marking luminance are presented to illustrate how the optical design of a pavement marking system controls nighttime visibility.
Laboratory Test of Driver Responses to Nine-Panel Logo Signs
Authors: Hummer Joseph E. , Maripalli Uday K.
Published: November 2008

When the number of businesses providing a certain service at an interchange exceeds the number of logo panels allowed per sign—currently six—the highway agency faces a dilemma. The agency could refuse to add more logos; this decision could mean more billboards; spread logos from one type of service onto several signs, perhaps using a mixed-use sign; or increase the number of logos allowed per sign. Allowing nine logos per sign would resolve the dilemma at many interchanges. The project objective was to determine the difficulty drivers reading nine-panel signs might have compared with their reading six-panel and mixed-use signs. The authors conducted a slide-based experiment in which volunteers were first given the name of a brand for which to scan. A realistic logo sign image was then shown for a short and varying time, and the subjects were asked whether the brand was on the sign. Six-panel signs had about 8% more correct responses than nine-panel signs and 5% more than mixed-use signs. Another useful finding was that the logo position on a sign made just a small difference in correct response rate. It was not surprising that six-panel and mixed-use signs generally performed better than nine-panel signs. Because the margin of the difference was small, the study team concluded that nine-panel logo signs performed well. If the use of nine-panel signs means drivers will not have to read billboards or a greater quantity of six-panel signs, drivers are likely to be as safe with nine-panel signs.
Driver Stopping Behavior on High-Speed Signalized Intersection Approaches
Authors: El-Shawarby Ihab , Amer Ahmed , Rakha Hesham
Published: November 2008

The research presented in this paper characterizes driver stopping behavior at the onset of a yellow phase on high-speed signalized-intersection approaches through the use of controlled field data gathered from 60 test subjects by means of an in-vehicle differential global positioning system. A total of 745 data records were available for analysis of all drivers who stopped at the onset of the yellow phase. These ranged from a minimum time to the stop bar (TTS) of 1.34 s to a maximum of 6.19 s. Statistical analyses were used to investigate the effects of the TTS bar, grade (uphill and downhill), age (younger than 40 years old, 40 to 59 years old, and 60 years of age or older), and gender on seven dependent measures of driver performance, including perception time, reaction time, perception–reaction time, braking time, stopping time, and stopping accuracy. The study demonstrated that driver perception time was not affected by TTS, while reaction time was dependent on TTS, roadway grade, and driver age. Younger drivers had longer reaction times than the older group, but they were able to stop over a shorter period of time, as they typically applied more aggressive braking rates. A lower perception–reaction time was found for drivers who had their foot lifted off the accelerator at the onset of the yellow phase. Male drivers showed slightly higher braking times than female drivers, with no significant differences between male and female drivers. Furthermore, the results demonstrated that drivers who tried to stop in short TTSs were more likely to stop downstream of the stop line and that older drivers were significantly more accurate when they stopped than other age groups.
Gate Rushing at Highway–Railroad Grade Crossings
Authors: Khattak Aemal J. , McKnight Gregory A.
Published: November 2008

This paper deals with the issue of aggressive motor vehicle drivers rushing through closed gates or gates in motion when trains are in close proximity to a highway–railroad grade crossing. The paper's objectives were to report drivers’ frequency of gate rushing and factors associated with it and to investigate drivers’ response to varying degrees of control exercised on their ability to rush through gates. Motor vehicle drivers at a highway–railroad grade crossing were observed by using video equipment before and after a plastic and rubber barrier was installed along the roadway centerline on both sides of the crossing. The installation was in two stages that progressively limited drivers’ ability to go through closed gates. During the first stage, the barriers on both sides of the crossing were installed such that they stopped short of the gates, while in the second stage they were fully extended to the gates. The expectation was that gate rushing will diminish when the barrier is erected but stops short of the gates and that it will further diminish when the barrier is fully extended to the gates. Data analysis showed a gate rush occurring about once every five train crossings; installation of the barrier along the roadway centerline on both sides of the crossing during the first stage reduced gate rushing by 37%. Contrary to the authors’ expectations, no additional reduction in gate rushing was observed when the barriers were fully extended to the gates. Instances of gate rushing increased with longer durations of road closures but decreased if crossing trains stopped on the tracks or if weather conditions were not favorable.
Forensic Analysis of Premature Surface Cracking in Full-Depth Asphalt Pavements on Plastic Clays
Authors: Shuler Scott
Published: November 2008

Premature cracking in new asphalt pavements before the pavements are opened to public traffic, before the development of the sites is completed, and before surrounding buildings are occupied is the focus of this paper. Previous studies have been conducted at individual sites to determine the cause of this phenomenon and have resulted in a variety of probable, but not conclusive, causes. This paper describes a forensic analysis that used interviews with principals experienced with this form of distress and the results of field and laboratory tests intended to expose commonality by soil type, pavement materials properties, construction sequence, and pavement design among several sites where cracking occurred and where cracking was not present. Six factors that were common at each site with cracking were detected: all cracks began at the surface of the pavement and propagated downward; the moisture contents of the subgrade soils beneath the cracks were higher than optimum, as measured by AASHTO T99; the densities of the subgrade soils beneath the cracks were lower than optimum, as measured by AASHTO T99; subgrade soils were classified as AASHTO A7; all pavements were full-depth asphalt placed directly on the subgrade; and all pavements were constructed in private developments with typical curb and gutter sections. In addition, similar pavements constructed on crushed stone bases in the vicinity of the full-depth pavements with the same construction and materials characteristics did not display this cracking. The results warrant a reduction in compaction moisture levels so that compaction densities can be increased when full-depth asphalt is used to pave over plastic clays.
Backcalculation of Dynamic Modulus from Resilient Modulus of Asphalt Concrete with an Artificial Neural Network
Authors: Andrew Lacroix , Kim Y. Richard , Ranjithan S. Ranji
Published: November 2008

The NCHRP Project 1-37A Guide for Mechanistic–Empirical Design of New and Rehabilitated Pavement Structures introduces the dynamic modulus (|E*|) as the material property for the characterization of hot-mix asphalt mixtures. This is a significant change from the resilient modulus used in the previous AASHTO Guide for the Design of Pavement Structures. One of the challenges of changing the material characterization is that databases, such as the Long-Term Pavement Performance Materials Database, contain older material characterization information. Thus, such databases must convert their data to the currently accepted standard (i.e., |E*|). Other investigators have presented evidence that the resilient modulus can be predicted from the dynamic modulus by using the theory of viscoelasticity. By using their prediction method, this study proposes the population of a database of measured dynamic moduli with the corresponding predicted resilient moduli to train an artificial neural network (ANN). The ANN model was verified with four 12.5-mm surface course mixtures with different aggregate types and binder types and one 25.0-mm base mixture. The dynamic moduli predicted from the measured resilient moduli with the trained ANN were found to be reasonable compared with the measured dynamic moduli.
Effect of Laboratory Data Range Selection in Permanent Deformation Characterization of Asphalt Mixtures
Authors: Diaz Luis G. , Archilla Adrian R.
Published: November 2008

As the power model parameters play a critical role in the permanent deformation characterization of asphalt mixtures and their direct use in pavement structural design methodologies becomes standard practice, all known sources of variability in their estimation should be considered. Although there is clear consensus in the ability of the power model to characterize the secondary stage of deformation properly, defining where this stage begins and ends is an arbitrary process, and therefore different parameter estimates could be obtained for the same mixture, potentially generating different design recommendations when they are used in the Guide for Mechanistic–Empirical Design of New and Rehabilitated Pavement Structures (referred to as MEPDG). The effect that laboratory data range selection has in the determination of the power model parameters was evaluated by using data from repeated load tests with short, medium, and long duration times performed with standard and modified asphalt mixtures. The results from the analysis indicate the potential for significant differences in the power model parameters because of data range selection alone during model fitting, even when the data selected are confined to the secondary deformation stage. The magnitude of the observed differences and its potential impact in rut depth prediction supports the need for the establishment of unified criteria for the selection of ranges of data from permanent deformation tests. As the potential implementation and acceptance of MEPDG will rely heavily on local calibration efforts, including permanent deformation laboratory testing, this paper proposes a procedure to unify the way in which the range of data used to estimate the parameters from the power model is selected.
Investigation of Simple Performance Characteristics of Plant-Produced Asphalt Mixtures in Tennessee
Authors: Huang Baoshan , Shu Xiang , Bass James
Published: November 2008

With the recent adoption of the dynamic modulus, flow number, and flow time tests as simple performance tests (SPTs) to complement the Super-pave® volumetric mixture design and the selection of dynamic modulus as a basic material property input in the new AASHTO 2002 M-E design guide, SPTs have been receiving more attention and have been more often used in the asphalt community. This paper presents the results from a laboratory study with the asphalt mixtures used in Tennessee obtained by SPTs. Eleven plant-produced mixtures with asphalt cements with different PGs and different aggregates were evaluated by the dynamic modulus and flow number tests. The asphalt pavement analyzer (APA) test was also included in this study to characterize the rutting resistance of asphalt mixtures. The results indicated that generally repeatable data can be obtained from the dynamic modulus test. The flow number test was able to identify the effects of both asphalt cement and aggregate in the rutting resistance of mixtures. The SPTs and APA test produced consistent results in this study.
Comparing MOBILE6.2 and Emfac2007 Emission Factors
Authors: Claggett Michael , Houk Jeffrey
Published: November 2008

At the top of the list of tools needed to forecast reliably any potential adverse health outcomes from proposed highway projects are, predictably, models of mobile source emission factors. A comparison of the two current regulatory models is provided: Emfac2007, developed by the California Air Resources Board for applications in California, and MOBILE6.2, developed by the U.S. Environmental Protection Agency for regulatory applications elsewhere in the United States. Pollutant emission factors computed by the models are evaluated. Although the two models share the same fundamental principle—that is, emissions from motor vehicles are based on testing with correction factors utilized to account for on-road vehicle use—the models produce strikingly divergent results. MOBILE6.2 tends to predict higher emission factors for carbon monoxide, volatile organic compounds, nitrogen oxides, and benzene compared with Emfac2007. In contrast, Emfac2007 predicts higher emission factors for particulate matter (PM) of size ≤2.5 μm and diesel PM. The reasons for these calculation differences are discussed. The implications pertaining to the evaluation of highway project alternatives are also discussed.
Approach to Development and Evaluation of Driving Cycles for Classified Roads Based on Vehicle Emission Characteristics
Authors: Yu Lei , Wang Ziqianli , Qiao Fengxiang , Qi Yi
Published: November 2008

The first objective of this study is to develop driving cycles for classified roads incorporating a vehicle's driving activities as well as emission characteristics by using the data collected by a portable emission measurement system, which was not available or has never been used in developing driving cycles. The second objective is to develop an approach to evaluate driving cycles in which the vehicle specific power, a parameter that can readily connect the driving modes with emissions, is used to evaluate how well the driving cycles can represent the driving and emission characteristics on real roads. A comparison is conducted of driving cycles developed by the proposed method versus the traditional methodology. Results show that driving cycles developed by the proposed method can better represent the emission characteristics of on-road vehicles.
Comparison of Technological and Operational Strategies to Reduce Trucking Emissions in Southern California
Authors: Facanha Cristiano , Ang-Olson Jeffrey
Published: November 2008

This study compares the cost-effectiveness and the emission reduction potential from selected trucking strategies in Southern California. The Ports of Los Angeles and Long Beach will have to accommodate substantial traffic growth in the next decades because of Asia Pacific corridor trade growth. Not only will California have to improve capacity and avoid gridlock, but it will also have to develop strategies that reduce emissions from goods movement. The Southern California Association of Governments and other agencies are developing major plans for goods movement infrastructure investments as well as technological and operational strategies that account for environmental performance. Beside future improvements in trucking emissions due to new emission standards, additional trucking strategies are evaluated in this analysis. They include truck replacement, truck repowering, truck retrofit with particulate matter control devices, and two operational strategies—a virtual container yard and an expanded incident management program that tackles incidents involving heavy-duty diesel trucks.
Mapping with a Consistent Wildlife Habitat Classification to Improve Transportation and Conservation Planning
Authors: O'Neill Thomas , Langhoff Cory , Johnson Amber
Published: November 2008

A basic tenet to streamline transportation and conservation planning is consistency. An overview is given of the steps necessary to create a consistent methodology for habitat assessment. This process was developed in the Pacific Northwest and combines three components for determining the baseline condition for fish and wildlife habitat. Each component captures a portion of the information necessary to assess wildlife habitats across large areas consistently. The first component is a hierarchical wildlife habitat classification scheme that can be mapped at various scales. The second piece is a relational database that ties multiple species–habitat relationships to the hierarchical classification scheme. Finally, the third component necessary is a consistent mapping methodology that can tie together both relational databases and classification schemes at various hierarchical scales. Each component is described, and a broad outline of how to combine these three components to determine the baseline habitat value for wildlife is offered. Examples are used to illustrate several products from this approach that are useful for transportation and conservation planning. Creating a consistent methodology for wildlife habitat assessment can help streamline transportation and conservation projects by enabling resource managers to determine baseline habitat values, focus the discussion on high-value areas, and improve mitigation efforts based on value rather than acreage.
Assessing Environmental Impact of Transport Noise with Wireless Sensor Networks
Authors: McDonald Paul , Geraghty Dermot , Humphreys Ivor , Farrell Stephen
Published: November 2008

Noise pollution from transportation systems devalues the environment and carries with it substantial social and economic costs. New legislation aims to reduce the impact of transport noise. This study outlines how wireless sensor networks can be used to assess accurately the socio-economic benefits of noise mitigation policies. Various economic methods of estimating the disamenity of noise are explored. Current practices for predicting the benefits of noise reduction strategies are examined, and the need for a long-term monitoring solution within the current system is observed. Sensor network with delay tolerance (SeNDT) units are presented as a wireless sensor networking device capable of monitoring environmental noise levels. Preliminary results from the SeNDT pilot study deployments are presented. These readings are used to estimate both the personally perceived and monetary gains resulting from the implementation of a new traffic policy that bans heavy goods vehicles in the city center of Dublin, Ireland. Initial calculations indicate that the ban will reduce the number of people annoyed by road traffic noise by approximately 8% and constitute a monetary saving of €77.50 ($105) per household in the area per year.
Shear Strength Characteristics of Recycled Glass
Authors: Ooi Phillip S. K. , Li Melanie M. W. , Sagario Michelle L. Q. , Song Yonghui
Published: November 2008

A comparison of the California bearing ratio (CBR) for recycled glass (RG) with other recycled materials and a basaltic virgin aggregate, all having similar gradations, revealed that the CBR of RG is superior to that of recycled asphalt pavement but less than that of recycled concrete and virgin aggregate. Direct shear tests were then run on the as-received gradation to derive strength parameters for RG prepared at very high and very low relative densities. For “dense” RG, the peak failure envelope was nonlinear with secant friction angles varying from 50° to 61°. For “loose” RG, the peak and critical state failure envelopes were linear with friction angles of 41° and 38°, respectively. Bolton's postulate that the peak friction angle is approximately equal to the critical friction angle plus 0.8 times the maximum angle of dilation works well for the RG tested in direct shear. A friction angle of 38° at critical state is significant, implying that RG has the potential to be used in even more foundation and ground improvement applications that are so often associated with transportation infrastructure construction. With increased use of recycled materials, civil engineers can help comply with the demand for sustainable development, a major theme in society today.
State of the Practice of Cable Barrier Systems
Authors: Sheikh Nauman M. , Alberson Dean C. , Chatham Linda S.
Published: November 2008

This paper presents the state of the practice of the use of cable barrier systems in the United States. A literature review was conducted to identify the types of cable barriers systems being used. The scope of this review included benefits of using cable barriers, available guidelines, policies or procedures related to barrier placement, and issues related to the maintenance and in-service performance of the cable barriers. A comprehensive survey was conducted to identify experiences, practices, and design and construction standards for the use of cable barrier systems. To improve survey quality, survey participants were people identified as managing the cable barrier systems firsthand. The participants were therefore likely to be most knowledgeable about the design and construction, maintenance, and overall experience of cable barrier usage. Concluding remarks about the state of the practice of cable barriers, along with areas of further research, are presented.
Community Context and Strip Mall Retail
Authors: Wolf Kathleen L.
Published: November 2008

Strip malls (or mini-malls) are a common land use, historically promoted by U.S. zoning practices that concentrate retail and commercial development in a narrow band along urban arterials and major streets. They are an entry-level retail niche offering opportunity for independent, start-up businesses that serve a limited market. Communities have begun to question land uses that enable efficient ingress and egress of vehicles in retail and commercial districts but give little attention to multimodal motility. Some communities are redeveloping small mall zones on the basis of “complete street” principles, expanding landscape plantings, and redeveloping the character of a business district. This study assessed public response to one element of small mall (re)development: landscape and vegetation. Prior studies indicated that consumer behavior is positively associated with city trees (urban forest) on multiple cognitive and behavioral dimensions. In mail surveys depicting varied roadside treatments, residents of three major cities in the Pacific Northwest were asked to indicate preferences and perceptions about proposed changes. Survey stimulus materials addressed visual quality, retail perceptions, patronage behavior, wayfinding, and willingness to pay for goods and services. Combined econometrics and psychometrics indicated that respondents prefer landscaped roadsides and report positive retail behavior, such as willingness to pay 8.8% more for goods and services in well-landscaped malls. Redevelopment and roadside management guidelines are proposed based on the research results, with implications for the economics of local communities.
Do Context-Sensitive Solutions Really Work?
Authors: Olszak Lisa , Goldbach Robert , Long James
Published: November 2008

Most state transportation agencies tout context-sensitive solutions (CSS) as an underlying principle in their approach to transportation project development. FHWA defines CSS as “a collaborative, interdisciplinary approach that involves all stakeholders to develop a transportation facility that fits its physical setting and preserves scenic, aesthetic, historic and environmental resources while maintaining safety and mobility.” The purpose of this research was to apply TRB CSS measurement criteria to test whether a well-planned CSS strategy contributes to a safe, cost-effective transportation project that is integrated within the fabric of the community. Olszak Management Consulting, Inc.—with support from FHWA and the Pennsylvania Turnpike Commission (PTC)—evaluated a CSS approach to an FHWA major highway project, The Mon/Fayette Expressway. PTC empowered five design advisory teams (DATs) made up of technical and community members to make decisions about critical design issues. Olszak's evaluation efforts focused on DAT stakeholder and multidisciplinary team performance activities that spanned 24 months of preliminary design. Surveys of designers, meeting facilitators, community stakeholders, and project leaders yielded strong evidence of satisfaction with both processes and outcomes. Cost savings were indicated and the project schedule was maintained. This paper details the DAT structure and functions, methods for documentation and information exchange, reliability of metrics, research findings, lessons learned, and suggestions for future research.
Students’ Perceptions of Difficulties in Cycling to School in Urban and Suburban Taiwan
Authors: Chang Hsin-Wen , Chang Hsin-Li
Published: November 2008

Previous research has identified the importance of cycling training programs and examined the relationship between cycling attitudes and the behavior of cyclists; another important factor that needs further research is obstacles to cycling in cities. This study investigates cycling difficulties confronted by Taiwanese students in the Hsin-Chu technopolis while riding their bikes to and from school. For an empirical perspective, a questionnaire was designed to collect data related to perceptions of cycling difficulties and to provide a descriptive analysis of students and their parents. Data were collected from samples in urban and suburban environments. The Rasch model was applied to analyze the cycling abilities of the students as well as their perceptions of cycling difficulty. Findings indicate that boys have better cycling abilities than girls, urban students have better abilities than suburban students, ability parallels age (older students have better cycling ability), and parents’ attitudes toward cycling to school parallel their children's abilities (parents of students with better cycling ability are less concerned). Various impediments to cycling are identified and, based on students’ perceptions, levels of difficulty are assigned. Implications of the results are discussed, and recommendations are offered, so as to facilitate matching bicycle use with Taiwan's status as a worldwide leader in bicycle manufacturing.
Effects of water stress at various growth stages on the physio-morphological characters and yield in chilli
Authors: Khan MAI , Farooque AM , Haque MA , Rahim MA , Hoque MA
Published: November 2008

An experiment was carried out during October 1999 to January 2000 in the field of Horticulture Department of Bangladesh Agricultural University, Mymensingh with two chilli accessions viz, C-0277 and C-0272 of moisture stress tolerant and susceptible type. The chilli accessions were put into trial under field condition to observe the effects of different water treatments imposed at their vegetative, flowering, and fruiting stages of growth and development. Results of the experiment revealed that accession C-0277 was water stress tolerant compared to accession C-0272. Watering at 4-day interval significantly gave the highest yield and dry matter. While, watering imposed in fruiting stage produced the maximum yield and dry matter in chilli. Key Words: Chilli accessions, field condition, water stress, yield. doi:10.3329/bjar.v33i3.1594 Bangladesh J. Agril. Res. 33(3) : 353-362, September 2008
Heterosis and combining ability for grain yield and its contributing characters in maize
Authors: Alam AKMM , Ahmed S , Begum M , Sultan MK
Published: November 2008

Combining ability analysis for grain yield and its contributing characters in maize were carried out in 5Ã5 diallel cross. The highest percentage of heterosis for grain per ear over mid parent and better parent were observed by the cross P2ÃP3. Crosses P1ÃP3 and P1ÃP5 showed significant negative heterosis for days to maturity. Significant general and specific combining ability variances were observed for all the characters except ear height. Almost equal role of additive and non-additive gene actions was observed for days to maturity. Additive genetic variance was preponderant for grains per ear and 1000-grain weight and non-additive gene action was involved in plant height, ear height, days to silking, and days to maturity. The inbred lines P2 and P5 were found to be best general combiner for 1000-grain weight. Key Words: Heterosis, combining ability, grain yield, maize. doi:10.3329/bjar.v33i3.1596 Bangladesh J. Agril. Res. 33(3) : 375-379, September 2008
Hurricane Footprints in Global Climate Models
Authors: Tapiador Francisco  J.
Published: November 2008

This paper addresses the identification of hurricanes in low-resolution global climate models (GCM). As hurricanes are not fully resolvable at the coarse resolution of the GCMs (typically 2.5 × 2.5 deg), indirect methods such as analyzing the environmental conditions favoring hurricane formation have to be sought. Nonetheless, the dynamical cores of the models have limitations in simulating hurricane formation, which is a far from fully understood process. Here, it is shown that variations in the specific entropy rather than in dynamical variables can be used as a proxy of the hurricane intensity as estimated by the Accumulated Cyclone Energy (ACE). The main application of this research is to ascertain the changes in the hurricane frequency and intensity in future climates.
EVALUATION OF THE INTENSITY OF ELECTROMAGNETIC FIELDS RADIATED BY RADAR
Authors: Maceika Kazimieras Vytautas
Published: November 2008

A method to calculate intensity of electromagnetic fields radiated by powerful radars equipment is proposed in this paper. In such radars exposures the energy may reach very high values of power density during peaks, but relatively low levels of power density averaged over time. Calculations are made for a TA 10MTD radar according to proposed equations. It is shown that an antenna 5 m in height radiates a power flux density at the height of a man's head more than forty times smaller than the level permitted by Lithuanian law ‐ 20.0 μW/cm2.

Santrauka

Pasiūlyta galingų radiolokatorių elektromagnetinės spinduliuotės skaičiavimo metodika. Atkreiptas dėmesys, kad skaičiavimuose reikia naudoti vidutinę jo spinduliuojamą galią. Vidutinę galią apsprendžia du faktai: radiolokatorius spinduliuoja trumpus radijo impulsus su, palyginti, ilgais tarpais tarp jų, be to besisukanti antena su siaura kryptingumo diagrama horizontalioje plokštumoje spinduliuoja į nurodytą erdvės tašką tik trumpą antenos sukimosi periodo dalį. Pagal pateiktas formules buvo atliktas įvertinamasis skaičiavimas radiolokatoriui TA 10MTD. Nustatyta, kad antena, sumontuota 5 m aukštyje, žmogaus galvos lygyje sukuria elektromagnetinės bangos galios srauto tankį, daug kartų mažesnį už Lietuvos normatyvais leistiną – 20,0 µW/cm2 ,todėl sanitarinė apsaugos zona nesusidaro.
Primer on disability: Why accessibility is important for all medical physicists
Authors: Jones Lindsay E. , Eliason Grace , Gupta Shivani , Jeong Elizabeth G. , Besemer Abigail , Sterling David A. , Fagerstrom Jessica M.
Published: February 2025

Disability and accessibility remain under‐addressed topics despite the increasing prevalence of disabled people in the workforce. In the field of medical physics, there is growing evidence that the proportion of people with one or more disabilities mirrors that of the US population. Addressing disability and accessibility is a crucial facet of the American Association of Physicists in Medicine's 2018 strategic goal to “champion equity, diversity, and inclusion in the field of medical physics.” This review aims to provide guidance on disability‐related topics in the context of the medical physics profession. An overview of current knowledge and recommendations is provided on essential topics such as how to comply with federal law, handle accommodation requests, and discuss disability using appropriate language. To that end, background information such as definitions, models, and classifications of disability is included. Beyond the essentials, this review also applies disability‐related concepts to improve overall efficiency and productivity, attract diverse talent, and demonstrate leadership as an individual or organization.
A semi‐supervised domain adaptation method with scale‐aware and global‐local fusion for abdominal multi‐organ segmentation
Authors: Han Kexin , Lou Qiong , Lu Fang
Published: February 2025

Background

Abdominal multi‐organ segmentation remains a challenging task. Semi‐supervised domain adaptation (SSDA) has emerged as an innovative solution. However, SSDA frameworks based on UNet struggle to capture multi‐scale and global information.

Purpose

Our work aimed to propose a novel SSDA method to achieve more accurate abdominal multi‐organ segmentation with limited labeled target domain data, which has a superior ability to capture the multi‐scale features and integrate local and global information effectively.

Methods

The proposed network is based on UNet. In the encoder part, a scale‐aware with domain‐specific batch normalization (SAD) module is integrated to adaptively extract multi‐scale features and to get better generalization across source and target domains. In the bottleneck part, a global‐local fusion (GLF) module is utilized for capturing and integrating both local and global information. They are integrated into the framework of self‐ensembling mean‐teacher (SE‐MT) to enhance the model's capability to learn common features across source and target domains.

Results

To validate the performance of the proposed model, we evaluated it on the public CHAOS and BTCV datasets. For CHAOS, the proposed method obtains an average DSC of 88.97% and ASD of 1.12 mm with only 20% labeled target data. For BTCV, it achieves an average DSC of 88.95% and ASD of 1.13 mm with 20% labeled target data. Compared with the state‐of‐the‐art methods, DSC and ASD increased by at least 0.72% and 0.33 mm on CHAOS, 1.29% and 0.06 mm on BTCV, respectively. Ablation studies were also conducted to verify the contribution of each component of the model. The proposed method achieves a DSC improvement of 3.17% over the baseline with 20% labeled target data.

Conclusion

The proposed SSDA method for abdominal multi‐organ segmentation has a powerful ability to extract multi‐scale and more global features, significantly improving segmentation accuracy and robustness.
Data‐Driven Adaptive Control With Global Sliding Behavior: A Dynamic Parametrization Approach
Authors: Sun Mingxuan , Zou Shengxiang , Li Wei
Published: February 2025

In this article, the problem of data‐driven adaptive control is addressed for a general class of non‐linear systems. Input/output difference representation is provided for the system undertaken, with which dynamic parametrization is applied for handling the involved non‐linearity. By underlining finite difference principle, this article proposes a design method of data‐driven adaptive control with guaranteed global sliding behavior, through estimation for the time‐varying parameters and compensation for the prediction error. The sliding behavior characterization is presented through an assessment of the resultant closed‐loop system by power‐rate rule. The derivations for the absolute attracting layer, steady‐state error band, and monotone decreasing region of the error dynamics are presented in detail. Numerical simulation is carried out to examine the error behavior and validate the effectiveness of the proposed control scheme.
Oklahoma bill would abolish mental health/substance use agency and replace it with corrections
Authors: Knopf Alison
Published: February 2025

A bill proposed by Oklahoma state representative Justin Humphrey, a Republican, would transfer all money and power from the Department of Mental Health and Substance Abuse Services to the state's Department of Corrections. Sources tell ADAW that this bill has no prospects of moving forward. According to the bill text, the move is “immediately necessary for the preservation of the public peace, health or safety, an emergency is hereby declared to exist, by reason whereof this act shall take effect and be in full force from and after its passage and approval. Last month, Humphrey also proposed a bill to rename the Oklahoma Department of Corrections (DOC) to the Oklahoma Department of Corruption.
All‐In‐One Double Perovskite Flexible Film with Highly Efficient Warm‐White Emission, Near‐Infrared Emission, and X‐Ray Radioluminescence
Authors: Peng Hui , Huang Wenjie , Kong Linghang , Yu Shuiyue , Zou Bingsuo
Published: February 2025

Recently, lead‐free double perovskites have gained much attention for their superior optoelectronic properties. However, realizing efficient white light and near‐infrared (NIR) emission, as well as bright radioluminescence (RL) in a single compound has not yet been reported. Herein, Bi3+/Mo4+‐codoped Cs2Ag0.6Na0.4InCl6 double perovskite is synthesized by a hydrothermal reaction. Under photoexcitation, the codoped compound exhibits highly efficient broadband warm‐white emission (610 nm) and NIR emission (930 nm), which can be attributed to self‐trapped exciton emission of Bi3+ and d–d transition of Mo4+, respectively. Interestingly, Bi3+/Mo4+‐codoped Cs2Ag0.6Na0.4InCl6 also emits strong radioluminescence with a light yield of 25100 photons per MeV under X‐ray irradiation. Based on Bi3+/Mo4+‐codoped Cs2Ag0.6Na0.4InCl6/PDMS flexible film, its applications in white light emitting diodes (WLED), NIR light source, and X‐ray scintillator are demonstrated, respectively, all of which exhibit remarkable optoelectronic properties. Finally, the as‐fabricated devices in white light, NIR, and X‐ray imaging are further demonstrated respectively, and the pixel‐level white light, NIR, and X‐ray image fusion is realized without pixel mismatch and complex imaging processing. Therefore, the internal information of the capsule wrapped with centrifuge tube and iron wire is successfully demonstrated through X‐ray to NIR image fusion.
Ultra‐Elastic, Durable, Bio‐Degradable, and Recyclable Pulp Foam as an Air Dielectric Substitute for Sustainable Capacitive Pressure Sensing
Authors: Cheng Na , Liu Chao , Gao Yufa , Wu Meiyan , Yu Guang , Chen Chaoji , Rahmaninia Mehdi , Shen Jing , Li Bin
Published: February 2025

Green carbon‐based cellulosic pulp foams with excellent renewable and biodegradable properties are promising alternatives to traditional petroleum‐based lightweight materials, for reducing carbon emission and plastic pollution. However, the fabrication of super‐elastic and durable pulp‐based foams for high‐value utilization remains challenging. Herein, a novel composite bio‐foam material is prepared by a simple strategy of wet foaming and ionically cross‐linking. The obtained foam assembled by cellulosic pulp fibers and polylactic acid (PLA) fibers at atmospheric pressure shows an oriented lamellar structure with interconnected macropores and super‐elastic property. The prepared PLA@Pulp‐20 foam shows a high compressive strain of up to 90% with the maximum stress of 150 kPa, while retaining ≈91% of its original height even after 30 000 compressive cycles (far superior to the reported pulp‐based foams with compressive cycles <10). Furthermore, the foam exhibits outstanding recyclability and stability in a wide range of temperature and humidity. Remarkably, the potential application of PLA@Pulp foam as a dielectric layer for capacitive sensors is first demonstrated because of its electrical non‐conductivity, and low dielectric constant (comparable to air). The corresponding device achieves non‐contact touch or contact touch sensing, demonstrating highly attractive performance in sustainable super‐elastic pressure sensing, monitoring, and beyond.
Direct Integration of Biomass‐Derived Furan Polymers for Enhanced Stability and Efficiency in Hybrid Perovskite Solar Cells
Authors: Lin Zilu , Li Yujia , Das Maloy , Liang Caihong , Xiao Xingchi , Yen Zhihao , Kulshreshtha Chandramouli , Chia Wei Min Luke , Lim Junan Aren , N'konou Kekeli , Sum Tze Chien , Mathews Nripan , Grimsdale Andrew C. , Ng Leonard W. T.
Published: February 2025

This study introduces a novel, biomass‐derived, furan‐based conjugated polymer, PBDF‐DFC, enabling a simplified direct precursor integration fabrication method for hybrid perovskite solar cells (HPSCs). Unlike traditional thiophene‐based polymers, PBDF‐DFC exhibits high solubility in perovskite precursor solvents, allowing direct incorporation into the precursor solution. This direct precursor integration approach significantly streamlines the fabrication process, reducing steps and potentially lowering production costs. The PBDF‐DFC‐modified HPSCs achieves a power conversion efficiency (PCE) of 21.39%, a 7.8% improvement over the 19.84% PCE of control devices. Moreover, these devices demonstrates enhanced stability under various environmental stresses, retaining 90% of their initial efficiency after over 1100 h of storage compared to 52% for control devices. X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy analyses reveals that PBDF‐DFC accumulates at grain boundaries, improving film crystallization and reducing defects. This dual innovation of a new polymer and simplified fabrication process presents a promising pathway for more efficient, stable, and potentially more sustainable HPSCs. The successful integration of PBDF‐DFC and the direct precursor integration method opens new avenues for streamlined production of high‐performance perovskite solar cells, addressing key challenges in scalability and environmental impact.
Tough and Elastic Anisotropic Triboelectric Materials Enabled by Layer‐by‐Layer Assembly
Authors: Liu Tao , Zhao Zhuo , Liang Rongrong , He Huanjie , Liu Yanhua , Yu Kang , Chi Mingchao , Luo Bin , Wang Jinlong , Zhang Song , Cai Chenchen , Wang Shuangfei , Nie Shuangxi
Published: February 2025

The synergistic integration of elastic porous material with self‐powered sensing capabilities holds immense promise for smart wearable devices. However, the intrinsic contradiction between elasticity and strength has hindered the mechanical performance of elastic porous materials. This research reports a diffusion‐driven layer‐by‐layer assembly strategy to enhance the mechanical strength of elastic porous materials. As a prerequisite, the anisotropic layered structure of natural materials is leveraged to endow the porous material with fundamental elasticity. Subsequently, vacuum and chemically‐assisted enhanced solvent diffusion are sequentially employed to assemble conductive and elastic layers on cellulose from the inside out. This endows the triboelectric material (TM) with exceptional mechanical properties (elastic strain range of 0–80%, compressive strength reaching 4.55 MPa). Utilizing the TM as a sensing material, a self‐powered sensor with a response time of 48 ms and a sensitivity of 0.57 kPa−1 is constructed. Moreover, the application of the sensor in a smart wearable helmet is demonstrated, enabling remote monitoring and traceability of head impact events. This research has overcome the incompatibility between the high strength and elasticity of porous materials and offers promising avenues for their utilization in smart wearable devices.