Image-Based Automated Width Measurement of Surface Cracking

The detection of cracks is an important monitoring task in civil engineering infrastructure devoted to ensuring durability, structural safety, and integrity. It has been traditionally performed by visual inspection, and the measurement of crack width has been manually obtained with a crack-width comparator gauge (CWCG). Unfortunately, this technique is time-consuming, suffers from subjective judgement, and is error-prone due to the difficulty of ensuring a correct spatial measurement as the CWCG may not be correctly positioned in accordance with the crack orientation. Although algorithms for automatic crack detection have been developed, most of them have specifically focused on solving the segmentation problem through Deep Learning techniques failing to address the underlying problem: crack width evaluation, which is critical for the assessment of civil structures. This paper proposes a novel automated method for surface cracking width measurement based on digital image processing techniques. Our proposal consists of three stages: anisotropic smoothing, segmentation, and stabilized central points by k-means adjustment and allows the characterization of both crack width and curvature-related orientation. The method is validated by assessing the surface cracking of fiber-reinforced earthen construction materials. The preliminary results show that the proposal is robust, efficient, and highly accurate at estimating crack width in digital images. The method effectively discards false cracks and detects real ones as small as 0.15 mm width regardless of the lighting conditions.

Analysis of Fine Crack Images Using Image Processing Technique and High-Resolution Camera

Visual inspections are performed to investigate cracks in concrete infrastructure. These activities require manpower or equipment such as articulated ladders. Additionally, there are health and safety issues because some structures have low accessibility. To deal with these problems, crack measurement with digital images and digital image processing (DIP) techniques have been adopted in various studies. The objective of this experimental study is to evaluate the optical limit of digital camera lenses as working distance increases. Three different lenses and two digital cameras were used to capture images of lines ranging from 0.1 to 0.5 mm in thickness. As a result of the experiments, it was found that many elements affect width measurement. However, crack width measurement is dependent on the measured pixel values. To accurately measure width, the measured pixel values must be in decimal units, but that is theoretically impossible. According to the results, in the case of 0.3 mm wide or wider cracks, a working distance of 1 m was secured when the focal length was 50 mm, and working distances of 3 m and 4 m were secured when the focal length was 100 mm and 135 mm, respectively. However, for cracks not wider than 0.1 mm, focal lengths of 100 mm and 135 mm showed measurability within 1 m, but a focal length of 50 mm was judged to hardly enable measurement except for certain working positions. Field measurement tests were conducted to verify measurement parameters identified by the results of the indoor experiment. The widths of actual cracks were measured through visual inspection and used for the analysis. From the evaluation, it was confirmed that the number of pixels corresponding to the working distance had a great influence on crack width measurement accuracy when using image processing. Therefore, the optimal distance and measurement guidelines required for the measurement of the size of certain objects was presented for the imaging equipment and optical equipment applied in this study.

Reliability of Markers for Breast Hypoplasia in the Early Postpartum Period

Background Breast hypoplasia is one reason for insufficient milk supply. Case reports use wide intra-mammary width and certain breast appearances as markers of breast hypoplasia. However, the reliability of these variables has not been determined. Research aims To test the (i) interrater and intrarater reliability of intra-mammary width measurement and interrater reliability of categorizing women’s breasts into breast types, and (ii) feasibility and acceptability of study procedures for the participants. Methods This was a prospective, longitudinal, non-experimental design with survey and observational components of a convenience sample of early postpartum women ( N = 31). Interrater and intrarater reliability were measured using intraclass correlation coefficient for agreement for intra-mammary width measurements. Interrater reliability was measured using weighted kappa for agreement for categorizing breast type. Feasibility and acceptability of study procedures were collected 1 month later. Results Excellent intrarater and interrater reliability for the intra-mammary width measurement (ICC = 0.99, 95% CI [0.99, 0.997] and ICC = 0.88, 95% CI [0.74, 0.94], respectively) and fair interrater reliability for breast type categorization (k = 0.35, 95% CI [−0.05, 0.75]) with high level of agreement between raters (97%) were achieved. Proportions of participants agreeing to breast photography and acceptability of study procedures were 68% (21/31) and 100% (28/28) respectively. Conclusion The excellent reliability for the intra-mammary width measurement means it provides a useful measure for future research. Since the “fair” reliability of categorizing breast type was due to lack of breast shape range in our sample, future research could assess the breasts of women with different medical profiles.

Distribusi frekuensi lebar anteroposterior sinus frontalis dengan radiograf lateral cephalometri berdasarkan usia dan jenis kelamin

Objectives: This research is aimed to determine the wide frequency distribution of anteroposterior frontal sinus with lateral cephalometric radiographs based on age and sex in West Jakarta, which is centered on RSGM FKG Trisakti University. Material and Methods: This research is using descriptive observational research design and the anteroposterior width measurement of the frontal sinus uses the Erturk measurement method. This study used 125 lateral cephalometric radiographs (40 males and 85 females) as samples which taken from a server at the Dental Radiology Installation, RSGM FKG Trisakti University. Results: The result showed that the smallest mean width of the anteroposterior frontal sinuses in males is at 7 years (5.4 mm) and the largest size is at 19 years (9.76 mm). Whereas the smallest mean width of anteroposterior frontal sinuses in females is at the age of 7 years (5.4 mm) and the largest size is at the age of 20 years (9.25 mm). The average width of anteroposterior frontal sinuses is 6.6 mm in males and 5.58 mm in females. Conclusion: Males have an average width of anteroposterior frontal sinuses that is larger than females and there are some decrease in size in some age groups. Variations in size can occur due to genetic and environmental factors.