scholarly journals Study on Air Void Characteristics and Hydraulic Characteristics of Porous Asphalt Concrete Based on Image Processing Technology

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Zhanqi Wang ◽  
Jianguang Xie ◽  
Lei Gao ◽  
Yanping Liu ◽  
Kuan Li
Keyword(s):  
Permeability Coefficient ◽  
Ct Images ◽  
Void Content ◽  
Cross Sectional ◽  
Air Voids ◽  
Porous Asphalt ◽  
Pore Structures ◽  
Drainage Capacity ◽  
The Relationship ◽  
Interconnected Pore

The appearance of porous asphalt (PA) pavement is to solve the problem of road ponding in rainy days. The internal air voids in PA pavement are the main functional structure that determines its drainage performance. It is of great practical significance to find out the relationship between void drainage capacity and air voids. This paper is aimed at researching the relationship between three-dimensional (3D) pore structures and drainage performance of PA concrete. Four samples were formed and scanned by CT equipment to obtain the internal cross-sectional CT images. Image dodging algorithm and OTSU method were conducted to deal with these CT images for segmenting them into three subimages (void image, asphalt mortar image, and aggregate image) according to the three components of PA concrete. The voids on void images were identified and classified into three groups according to the three kind of pores (interconnected pore, semi-interconnected pore, and closed pore) and reshaped them into 3D pore structures according to the overlapping principle. Then, the volume and size distribution of the pores was analyzed. Besides, this research mainly focused on the influence of several parameters obtained from interconnected pores on the drainage performance of PA concrete at last. The permeability coefficient of PA concrete samples was tested, and equations between permeability coefficient and void content were fitted linearly. The distribution of hydraulic radius and cross-sectional area ratio was calculated and researched by statistical methods. A new parameter, perimeter variation coefficient, is proposed to study the influence of boundary wall roughness on the drainage performance. At last, equivalent drainage channel was drawn to reflect the drainage capacity of PA concrete.

The Influence of Porous Asphalt Pavement Based on DEMATEL

2012 ◽  
Vol 178-181 ◽  
pp. 1333-1337 ◽  
Author(s):  
Ching Tsung Hung ◽  
Shih Huang Chen ◽  
Chia Chen Wu
Keyword(s):  
High Performance ◽  
Asphalt Pavement ◽  
Laboratory Method ◽  
Road User ◽  
Porous Asphalt ◽  
Decision Method ◽  
Drainage Capacity ◽  
Pavement Construction ◽  
The Relationship ◽  
Multiple Conditions

Taiwan position is in the subtropics, the climate is high temperature and much rains of year. Freeway mostly uses traditional dense grade in pavement construction, so the pavement could not remove water quickly in rainy day. It will deteriorate by rutting and aging, due to increasing maintenance frequency and cost. Porous asphalt pavement has high performance on road user safe and amenity in many countries. But the prescription in porous asphalt is Variable, for example, the fiber has miner and wood. Base on multiple conditions, the best performance can choice by multiple criteria decision method. This methodology needs the criteria under independent, but the real world is not. The study use Decision-Making Trial and Evaluation Laboratory method to establish the relationship in criteria. With result, the drainage capacity was the important factor in porous asphalt pavement.

Research on Effect of Equivalent Diameter of Voids on Sound Absorption Performance of Porous Asphalt Concrete Based on Grey Entropy Method

2020 ◽  
Vol 861 ◽  
pp. 414-420
Author(s):  
Ming Xi Liu ◽  
Jian Guang Xie ◽  
Zhan Qi Wang ◽  
Yan Ping Liu
Keyword(s):  
Asphalt Concrete ◽  
Sound Absorption ◽  
Traffic Noise ◽  
Entropy Method ◽  
Equivalent Diameter ◽  
Air Voids ◽  
Porous Asphalt ◽  
Absorption Performance ◽  
The Relationship ◽  
Porous Asphalt Concrete

The sound absorption performance of porous asphalt concrete (PAC) is inseparable from the sizes of voids, as different sizes of voids have different absorption effects on noise in different frequency bands. However, the relationship between the two is not clear. In this study, the equivalent diameter of voids was obtained by the proposed image segmentation algorithm based on the square area, then grey entropy method was used to analyze the effect of different equivalent diameter of voids on the sound absorption performance of PAC in the frequency range of traffic noise. The results show that with the increase of air voids, the peak and average sound absorption coefficient of PAC increase, the sound absorption performance of PAC is improved; and the sound absorption performance of PAC is mainly affected by the equivalent diameter of voids of 3-4mm.

scholarly journals Virtual Asphalt to Predict Roads’ Air Voids and Hydraulic Conductivity

2018 ◽  
Author(s):  
Mustafa Aboufoul ◽  
Andrea Chiarelli ◽  
Isaac Triguero ◽  
Alvaro Garcia
Keyword(s):  
Hydraulic Conductivity ◽  
Asphalt Mixtures ◽  
Maximum Aggregate Size ◽  
High Dispersion ◽  
Void Content ◽  
Air Voids ◽  
Porous Asphalt ◽  
Pore Networks ◽  
Asphalt Materials ◽  
Air Void

This paper investigates the effects of air void topology on hydraulic conductivity in asphalt mixtures with porosity in the range 14%-31%. Virtual asphalt pore networks were generated using the Intersected Stacked Air voids (ISA) method, with its parameters being automatically adjusted by the means of a differential evolution optimisation algorithm, and then 3D printed using transparent resin. Permeability tests were conducted on the resin samples to understand the effects of pore topology on hydraulic conductivity. Moreover, the pore networks generated virtually were compared to real asphalt pore networks captured via X-ray Computed Tomography (CT) scans. The optimised ISA method was able to generate realistic 3D pore networks corresponding to those seen in asphalt mixtures in term of visual, topological, statistical and air void shape properties. It was found that, in the range of porous asphalt materials investigated in this research, the high dispersion in hydraulic conductivity at constant air void content is a function of the average air void diameter. Finally, the relationship between average void diameter and the maximum aggregate size and gradation in porous asphalt materials was investigated.

Coping Style as a Mediator of the Relationship Between Depressive Symptoms and Deliberate Self-Harm

Crisis ◽  
2011 ◽  
Vol 32 (5) ◽  
pp. 272-279 ◽  
Author(s):  
Allison S. Christian ◽  
Kristen M. McCabe
Keyword(s):  
Depressive Symptoms ◽  
Undergraduate Students ◽  
Cross Sectional Study ◽  
Self Report ◽  
Hierarchical Regression ◽  
Cross Sectional ◽  
Deliberate Self Harm ◽  
Self Blame ◽  
Self Harm ◽  
The Relationship

Background: Deliberate self-harm (DSH) occurs with high frequency among clinical and nonclinical youth populations. Although depression has been consistently linked with the behavior, not all depressed individuals engage in DSH. Aims: The current study examined maladaptive coping strategies (i.e., self-blame, distancing, and self-isolation) as mediators between depression and DSH among undergraduate students. Methods: 202 students from undergraduate psychology courses at a private university in Southern California (77.7% women) completed anonymous self-report measures. Results: A hierarchical regression model found no differences in DSH history across demographic variables. Among coping variables, self-isolation alone was significantly related to DSH. A full meditational model was supported: Depressive symptoms were significantly related to DSH, but adding self-isolation to the model rendered the relationship nonsignificant. Limitations: The cross-sectional study design prevents determination of whether a casual relation exists between self-isolation and DSH, and obscures the direction of that relationship. Conclusions: Results suggest targeting self-isolation as a means of DSH prevention and intervention among nonclinical, youth populations.

Authoritative Maternal Parenting Associates With the Explicit Need for Autonomy

2020 ◽  
Vol 41 (2) ◽  
pp. 110-116
Author(s):  
Jonathan E. Ramsay
Keyword(s):  
University Students ◽  
Parenting Style ◽  
Cross Sectional ◽  
Perceived Parenting ◽  
Maternal Parenting ◽  
Retrospective Design ◽  
Dependent Variables ◽  
Paternal Parenting ◽  
The Relationship

Abstract. Previous research suggests that parenting style influences the development of the needs for achievement, power, and affiliation. The present study investigated the relationship between parenting style and another important motive disposition – the need for autonomy – in a sample of Singapore university students ( N = 97, 69% female), using a cross-sectional and retrospective design. It was predicted that an authoritative perceived parenting style would relate positively to the implicit need for autonomy ( nAut), the explicit need for autonomy ( sanAut), and the congruence between these two motive dispositions. Authoritative maternal parenting was found to positively associate with sanAut, while maternal parenting was not found to associate with nAut, or with nAut/ sanAut congruence. Paternal parenting was not associated with any of the dependent variables.

HUBUNGAN KUALITAS KEHIDUPAN KERJA TERHADAP KINERJA PERAWAT PELAKSANA

2019 ◽  
Vol 9 (4) ◽  
pp. 413-420
Author(s):  
Amella Gusty ◽  
Dachriyanus Dachriyanus ◽  
Leni Merdawati
Keyword(s):  
District Hospital ◽  
Simple Random Sampling ◽  
Work Life ◽  
Quality Of Work Life ◽  
P Value ◽  
Work Context ◽  
Cross Sectional ◽  
Quality Of Work ◽  
The Relationship

Kinerja perawat merupakan hasil yang dicapai dalam melaksanakan asuhan keperawatan di rumah sakit. Terciptanya asuhan keperawatan yang optimal sangat diperlukan dukungan dari pihak rumah sakit salah satunya adalah menciptakan kualitas kehidupan kerja baik bagi perawat. Penelitian ini bertujuan untuk mengetahui hubungan antara kualitas kehidupan kerja terhadap kinerja perawat pelaksana di RSUD Teluk Kuantan. Jenis penelitian kuantitatif dengan pendekatan cross sectional. Jumlah sampel 120 responden yang diperoleh melalui proportionate simple random sampling. Hasil penelitian menunjukkan kualitas kehidupan kerja perawat RSUD Teluk Kuantan berada pada kategori sedang, kinerja perawat berada pada kategori kurang baik. Berdasarkan analisis kedua variabel teridentifikasi bahwa tidak ada hubungan antara kualitas kehidupan kerja dengan kinerja perawat pelaksana dengan  p value 0,817. Dimensi work context merupakan komponen yang memiliki hubungan dengan kinerja perawat pelaksana dengan p value 0,008, dimensi work life  tidak berhubungan secara signifikan dengan kinerja perawat. Kesimpulan penelitian diketahui tidak ada hubungan antara kualitas kehidupan kerja dengan kinerja perawat pelaksana. Ada hubungan dimensi work context dengan kinerja perawat pelaksana. Tidak ada hubungan dimensi work life dengan kinerja perawat.   Kata kunci: kualitas kehidupan kerja, kinerja, perawat pelaksana   THE RELATIONSHIP BETWEEN THE QUALITY OF WORK LIFE AND THE PERFORMANCE OF IMPLEMENTERS NURSES   ABSTRACT Nurse performance is the result achieved in implementing nursing care in a hospital. The creation of optimal nursing care is very much needed support from the hospital, one of which is to create a good quality of work life for nurses. This study aims to determine the relationship between the quality of work life and the performance of nurses at the Kuantan District Hospital. This type of quantitative research with cross sectional approach. The number of samples of 120 respondents obtained through proportionate simple random sampling. The results showed that the quality of work life of nurses at the Kuantan District Hospital was in the medium category, the nurses' performance was in the unfavorable category. Based on the analysis of the two variables, it was identified that there was no relationship between the quality of work life with the performance of implementing nurses with a p value of 0.817. The work context dimension is a component that has a relationship with the performance of nurses implementing with p value 0.008, the dimension of work life does not significantly correlate with nurse performance. The conclusion of the research is that there is no relationship between the quality of work life and the performance of the implementing nurses. There is a relationship between the dimensions of the work context and the performance of the nurses. There is no relationship between the dimensions of work life and nurse performance.   Keywords: quality of work life, performance, implementers nurse

HUBUNGAN KOMUNIKASI TERAPEUTIK PERAWAT DENGAN KECEMASAN ANAK USIA PRASEKOLAH AKIBAT HOSPITALISASI

2019 ◽  
Vol 9 (2) ◽  
pp. 135-140
Author(s):  
Qurrotul Aeni ◽  
Andriyani Mustika Nurwijayanti ◽  
Muhammad Khabib Burhanuddin Iqomh
Keyword(s):  
Research Data ◽  
School Age Children ◽  
P Value ◽  
School Age ◽  
Therapeutic Communication ◽  
Cross Sectional ◽  
Communication Anxiety ◽  
Children’S Anxiety ◽  
The Relationship ◽  
Severe Anxiety

Introduction: anxiety is a condition that will be experienced by children who experience hospitalization and must get attention and management. Anxiety during hospitalization that is not properly addressed will hinder treatment and affect child development. The purpose of the study: to determine the relationship between therapeutic communication nurses and the anxiety of preschool children due to hospitalizationMethod: The study design used descriptive correlation with a cross-sectional approach. The number of samples is 31 with purposive sampling. Collecting research data using a questionnaire.Results: The results showed a majority of therapeutic communication was 61.3%, anxiety in children due to hospitalization of 100% with severe anxiety was 58.1%, there was a relationship between therapeutic communication and children's anxiety (p = 0.001). Suggestions need to be carried out further research on the factors that influence the low therapeutic communication in nurses.Discussion: The results of the statistical analysis using the Spearman's Rho test got p value 0.001 (p <0.05) the relationship between therapeutic communication and the anxiety of pre-school age children who experienced hospitalization, therapeutic communication can be used as an action to prevent anxiety due to hospitalization in pre-school age children.Suggestion: need to do further research on the factors that influence the low therapeutic communication in nurses Keywords: therapeutic communication, anxiety, hospitalization.  

STRATEGI KOPING ORANG TUA TERHADAP ANAK AUTIS DAN POLA ASUH ORANG TUA

2018 ◽  
Vol 11 (2) ◽  
pp. 196-204
Author(s):  
Asirotul Ma’rifah ◽  
Naning Puji Suryantini Suryantini ◽  
Rina Mardiyana
Keyword(s):  
Coping Strategies ◽  
Sampling Technique ◽  
Children With Autism ◽  
Adaptive Coping ◽  
Autistic Children ◽  
Cross Sectional ◽  
Authoritarian Parenting ◽  
Cross Tabulation ◽  
Relationship Of ◽  
The Relationship

Autism is still a nightmare for most parents. Parents with autism can be very stressful when dealing with a hyperactive child's behavior, aggressive and passive. Stress experienced by parents of children with autism will affect the ability of parents in the parenting role, especially in relation to coping strategies have in dealing with problems of children. The participation of parents is crucial the success of socializing with children with autism in the general population. This study aims to determine the relationship of coping strategies parents of autistic children and parenting parents. This type of research is an analytic correlation with cross sectional approach. The population in this study were all parents of autistic children in SLB Muhammadiyah Mojokerto numbering 15 people. Samples in this study were all parents of autistic children in SLB Muhammadiyah Mojokerto which totaled 15 people by using total sampling technique. Collecting data using questionnaires. Data analized use cross tabulation, presented in a frequency distribution. On cross-tabulation obtained results tend to use maladaptive coping strategies permissive parenting that is 8 (53.3%), there are also respondents who use adaptive coping strategies using authoritarian parenting as much as one person (16.7%), and adaptive coping strategies tend using democratic parenting style as much as 5 people (33.3%). Expected parents still seeking information to broaden their parents on coping strategies of parents of autistic children and parenting parents as well as parents to give special attention for children with autism to the development and advancement of their lives because they have the same rights as any other normal child.

IDENTIFIKASI SERTA HUBUNGAN KONSTRUKSI SUMUR GALI TERHADAP KANDUNGAN COLIFORM PADA AIR SUMUR GALI DI DUSUN JIKEN KABUPATEN LOMBOK TIMUR

2019 ◽  
Vol 7 (2) ◽  
pp. 115
Author(s):  
Dini Yuliansari
Keyword(s):  
Cross Sectional Study ◽  
Coliform Bacteria ◽  
Well Water ◽  
Chi Square ◽  
Cross Sectional ◽  
Content Variable ◽  
Chi Square Test ◽  
Dug Wells ◽  
Dug Well ◽  
The Relationship

The well is one of the source water used for bathing, washing, and drinking by the citizens in Jiken Hamlet, Rarang Village, Terara Sub-District. Poor dug well construction conditions can affect the amount of coliform bacteria contained in the dug well water. The purpose of this study is to identify the construction of dug wells and the content of coliform bacteria in dug well water and determine the relationship between dug well construction and the content of coliform bacteria. This research is analytic with a cross sectional study design. The results were obtained from 11 samples of dug wells which were observed in construction and the coliform content was known that all samples did not requirements as good dug well construction. Coliform content test results showed that as many as 5 dug well water samples did not pass the clean water quality standards. The results of data analysis with the chi-square test variable construction of dug wells with coliform content variable  showed 0,172 > 0,05, then the concluded is the dug well not suitable to use by people in that area as a source of water for daily needs.

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