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Hispidulin is a natural bioactive flavonoid that has been studied for its potential therapeutic properties, including its anti-inflammatory, antioxidant, and neuroprotective effects. The aim of this study was to explore whether hispidulin could inhibit the endothelial inflammation triggered by Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS). The adhesion of monocytes to the vascular endothelium was evaluated through in vitro and ex vivo monocyte adhesion assays. We analyzed the migration of monocytes across the endothelial layer using a transmigration assay. The results showed that treatment with hispidulin decreased the P. gingivalis LPS-induced adhesion of monocytes to endothelial cells and their migration by suppressing the P. gingivalis LPS-triggered expression of intercellular adhesion molecule-1 (ICAM-1) through downregulating nuclear factor-қB (NF-қB). In addition, hispidulin inhibited P. gingivalis LPS-induced mitogen-activated protein kinases (MAPKs) and AKT in endothelial cells. Altogether, the results indicate that hispidulin suppresses the vascular inflammation induced by P. gingivalis LPS. Mechanistically, it prevents the adhesion of monocytes to the vascular endothelium and migration and inhibits NF-қB, MAPKs, and AKT signaling in endothelial cells. [ABSTRACT FROM AUTHOR]

Airlines provide one of the most popular and important transportation services for passengers. While the importance of the airline industry is rising, flight cancellations are also increasing due to abnormal weather factors, such as rainfall and wind speed. Although previous studies on cancellations due to weather factors considered both aircraft and weather factors concurrently, the complex network studies only treated the aircraft factor with a single-layer network. Therefore, the aim of this study was to apply a multilayer complex network (MCN) method that incorporated three different factors, namely, aircraft, rainfall, and wind speed, to investigate aircraft cancellations at 14 airports in the Republic of Korea. The results showed that rainfall had a greater impact on aircraft cancellations compared with wind speed. To find out the most important node in the cancellation, we applied centrality analysis based on information entropy. According to the centrality analysis, Jeju Airport was identified as the most influential node since it has a high demand for aircraft. Also, we showed that characteristics and factors of aircraft cancellation should be appropriately defined by links in the MCN. Furthermore, we verified the applicability of the MCN method in the fields of aviation and meteorology. It is expected that the suggested methodology in this study can help to understand aircraft cancellation due to weather factors. [ABSTRACT FROM AUTHOR]

Accurate pollutant prediction is essential in fields such as meteorology, meteorological disasters, and climate change studies. In this study, long short-term memory (LSTM) and deep neural network (DNN) models were applied to six pollutants and comprehensive air-quality index (CAI) predictions from 2015 to 2020 in Korea. In addition, we used the network method to find the best data sources that provide factors affecting comprehensive air-quality index behaviors. This study had two steps: (1) predicting the six pollutants, including fine dust (PM10), fine particulate matter (PM2.5), ozone (O3), sulfurous acid gas (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO) using the LSTM model; (2) forecasting the CAI using the six predicted pollutants in the first step as predictors of DNNs. The predictive ability of each model for the six pollutants and CAI prediction was evaluated by comparing it with the observed air-quality data. This study showed that combining a DNN model with the network method provided a high predictive power, and this combination could be a remarkable strength in CAI prediction. As the need for disaster management increases, it is anticipated that the LSTM and DNN models with the network method have ample potential to track the dynamics of air pollution behaviors. [ABSTRACT FROM AUTHOR]

A 1.2-Mpixel indirect time-of-flight (ToF) CMOS image sensor is presented to lower peak current and to cancel out multi-user interference. The proposed 4-tap 3.5- $\mu \text{m}$ demodulation pixel is optimally designed to improve quantum efficiency (QE) and demodulation contrast (DC). A new “multiple-interleaving” scheme is proposed to reduce the peak current and self-compensate fixed-pattern phase noise (FPPN) with the minimal side effect of DC imbalance. To cancel out interference from the other ToF sensors, a multi-user interference cancellation (MUIC) scheme based on pseudorandom modulation is adopted. From the measurement results, we achieve a high QE of 38% at 940 nm and a high DC of 96% and 80% at 100- and 200-MHz modulation frequencies, respectively. With the superior pixel performance, the depth noise of <0.92% and <0.3% is achieved at the full and 2 $\times $ 2 binning modes, respectively. The multiple-interleaving scheme suppresses the peak current to less than 0.9 A and removes the column FPPN with constant DC for the whole pixel array. The proposed MUIC proves that at least two interferers can be successfully rejected. The sensor chip is fabricated in a two-stack process with 65 nm for the top die and 65 nm for the bottom die. [ABSTRACT FROM AUTHOR]

Featured Application: In this study, the influence of neutron irradiation on the mechanical properties of nuclear pressure vessel materials is investigated using two independent methods of nondestructive magnetic testing. A correlation was found between magnetic characteristics and neutron irradiation-induced damage, regardless of the applied measurement technique. Additionally, by merging the outcome of both testing methods and applying a calibration/training procedure, the damage to reactor steel was successfully predicted. The results are helpful for the potential future practical application of these techniques to the regular inspection of nuclear reactors. The embrittlement of two types of nuclear pressure vessel steel, 15Kh2NMFA and A508 Cl.2, was studied using two different methods of magnetic nondestructive testing: micromagnetic multiparameter microstructure and stress analysis (3MA-X8) and magnetic adaptive testing (MAT). The microstructure and mechanical properties of reactor pressure vessel (RPV) materials are modified due to neutron irradiation; this material degradation can be characterized using magnetic methods. For the first time, the progressive change in material properties due to neutron irradiation was investigated on the same specimens, before and after neutron irradiation. A correlation was found between magnetic characteristics and neutron-irradiation-induced damage, regardless of the type of material or the applied measurement technique. The results of the individual micromagnetic measurements proved their suitability for characterizing the degradation of RPV steel caused by simulated operating conditions. A calibration/training procedure was applied on the merged outcome of both testing methods, producing excellent results in predicting transition temperature, yield strength, and mechanical hardness for both materials. [ABSTRACT FROM AUTHOR]

During the braking process, frictional heat generated between a disc and a pad can lead to high temperatures. The location of friction blocks on the brake pad can lead directly to differences in friction contact time and friction speed at each point on the brake disc surface, this can lead to non-uniform temperature distribution on the brake disc surface. In this paper, the optimum design for friction blocks on a brake pad is investigated using the design of experiments (DOE) of Taguchi approach and response surface method (RSM) with an aim to minimize the deviation in the rate of friction heating in each area along the radial direction of brake disc. 18 design variables on 2 levels are adjusted. A table of orthogonal arrays, L32 (218), is used. Finite element analysis (FEA) is performed to analyze the mean squared error (MSE) values in the temperature deviations from frictional heat, the disc's thermo-mechanical characteristics are taken into account. Analysis of variance (ANOVA) is carried out using the data gathered from the DOE stage, we find 7 significant factors among the design variables. A meta-model using RSM is proposed for reduction of temperature deviations over the brake disc. An optimized brake pad is analyzed in terms of the temperature and thermal stress imparted on the brake disc, this optimized pad is then compared with the original pad. The maximum temperatures of the optimized pad and original pad were 399.8 °C and 480.6 °C, respectively. The thermal stress of the optimized pad and original pad were 640.4 MPa and 721.4 MPa, respectively. In the optimized model, the size of the hot band on the disc is larger than that from the original model, so the thermal stress distribution on the disc is smaller. Finally, the optimized pad was found to give significant performance benefits with a 16.8 % decrease in maximum temperature and 11.2 % decrease in thermal stress. [ABSTRACT FROM AUTHOR]

A nondestructive testing device, consisting of a scanner and signal processing circuits was developed to detect cracks in turbine disk roots. The scanner consists of a longitudinal feeder and a fir-tree-shaped sensor probe. The feeder inserted the sensor probe along the grooves of the turbine blade attachment. Meanwhile, permanent magnets were placed in opposite direction, to generate a closed magnetic field between the magnetic sensors located on the crests of the sensor probe. The fatigue crack in the turbine disk root occurred in the circumferential direction of the turbine. As a result, magnetic flux leakage was caused by disturbing the flow of closed magnetic field by permanent magnets. The magnetic flux leakage was measured by a magnetic sensor. The effectiveness of the proposed device has been verified using artificial defects introduced into the turbine disk roots by electric discharge machining. [ABSTRACT FROM AUTHOR]

Background Macaque species share >93% genome homology with humans and develop many disease phenotypes similar to those of humans, making them valuable animal models for the study of human diseases (e.g. HIV and neurodegenerative diseases). However, the quality of genome assembly and annotation for several macaque species lags behind the human genome effort. Results To close this gap and enhance functional genomics approaches, we used a combination of de novo linked-read assembly and scaffolding using proximity ligation assay (HiC) to assemble the pig-tailed macaque (Macaca nemestrina) genome. This combinatorial method yielded large scaffolds at chromosome level with a scaffold N50 of 127.5 Mb; the 23 largest scaffolds covered 90% of the entire genome. This assembly revealed large-scale rearrangements between pig-tailed macaque chromosomes 7, 12, and 13 and human chromosomes 2, 14, and 15. We subsequently annotated the genome using transcriptome and proteomics data from personalized induced pluripotent stem cells derived from the same animal. Reconstruction of the evolutionary tree using whole-genome annotation and orthologous comparisons among 3 macaque species, human, and mouse genomes revealed extensive homology between human and pig-tailed macaques with regards to both pluripotent stem cell genes and innate immune gene pathways. Our results confirm that rhesus and cynomolgus macaques exhibit a closer evolutionary distance to each other than either species exhibits to humans or pig-tailed macaques. Conclusions These findings demonstrate that pig-tailed macaques can serve as an excellent animal model for the study of many human diseases particularly with regards to pluripotency and innate immune pathways. [ABSTRACT FROM AUTHOR]

The threaded fasteners are typical machine components in tightening of the machine parts and structures. In addition, as threaded fasteners are easy to maintenance, these are used extensively from large structures to small electronic devices. However, after the clamping, if repetitive load is applied to the bolt/screw, loosening of the screw occurs. In this study, clamping analysis and loosening analysis are carried out for the M12 bolts which are used for the wheels of commercial vehicles. Since it is difficult to carry out test and finite element analysis (FEA) for the wheels of commercial vehicles, we propose a complex structure to deal with these problems. Through the test and FEA, the clamping force and the loosening load of bolt are derived. Not only the reduction of clamping force but also displacement of the complex structure subjected to load can indicate the loosening of the bolt. Three equivalent models are proposed to replace a detailed model for reduction of the analysis time and cost. Then, the three equivalent models are forms of rigid beam — beam — pretension (RBP), shell — beam — pretension (SBP) and shell — beam — temperature (SBT), respectively. Among these forms, the SBT model is most similar with analysis results of the detailed model. The difference between the analysis results of the detailed model and the SBT model was only 5 %. Based on the SBT model and the detailed model, it is applied to the wheel of the commercial vehicles to be verified. Then, the changes in the clamping force of the detailed model and the SBT model are identified as similar, proving the validity of the equivalent. [ABSTRACT FROM AUTHOR]

This paper presents an algorithm that estimates the presence, location, shape, and depth of flaws using a bobbin-type magnetic camera consisting of bobbin probes and a bobbin-type integrated giant magnetoresistance (GMR) sensor array (BIGiS). The presence of the flaws is determined by the lobe path of the Lissajous curves obtained from bobbin coil with respect to the applied frequency. The location of the flaw, i.e., whether it is an inner diameter (ID) or outer diameter (OD) flaw, can be determined from the rotational direction of the lobe with respect to the frequency change. The shape of the flaw is then determined from the area of the lobe and the BIGiS image. At this stage, multi-site damage can be determined from the BIGiS image. The effectiveness of the flaw classification algorithm was evaluated using various types of artificial flaws introduced into small-bore tube test specimens made of austenitic stainless steel. [ABSTRACT FROM AUTHOR]

Nondestructive examination and evaluation system for high pressure feed water heat exchanger tubes in nuclear power plant was developed. Differential-type bobbin coils made of copper wire are placed on both sides of GMR sensors arranged in a ring shape. If alternating current (AC) is applied to the bobbin coils, then an inductive current is occurred in circumferential direction of the tube to be examined. Under these conditions, eddy currents are generated around the defect. Because the time-varying magnetic field is distorted by eddy current that is generated around the defect, the shapes and dimensions of defect can be quantitatively evaluated with cylindrical arrayed GMR sensors. The result was verified by the artificial defects fabricated in a small diameter heat exchanger tube. [ABSTRACT FROM AUTHOR]

Background: Genomic data have become major resources to understand complex mechanisms at fine-scale temporal and spatial resolution in functional and evolutionary genetic studies, including human diseases, such as cancers. Recently, a large number of whole genomes of evolving populations of yeast (Saccharomyces cerevisiae W303 strain) were sequenced in a time-dependent manner to identify temporal evolutionary patterns. For this type of study, a chromosome-level sequence assembly of the strain or population at time zero is required to compare with the genomes derived later. However, there is no fully automated computational approach in experimental evolution studies to establish the chromosome-level genome assembly using unique features of sequencing data. Methods and results: In this study, we developed a new software pipeline, the integrative meta-assembly pipeline (IMAP), to build chromosome-level genome sequence assemblies by generating and combining multiple initial assemblies using three de novo assemblers from short-read sequencing data. We significantly improved the continuity and accuracy of the genome assembly using a large collection of sequencing data and hybrid assembly approaches. We validated our pipeline by generating chromosome-level assemblies of yeast strains W303 and SK1, and compared our results with assemblies built using long-read sequencing and various assembly evaluation metrics. We also constructed chromosome-level sequence assemblies of S. cerevisiae strain Sigma1278b, and three commonly used fungal strains: Aspergillus nidulans A713, Neurospora crassa 73, and Thielavia terrestris CBS 492.74, for which long-read sequencing data are not yet available. Finally, we examined the effect of IMAP parameters, such as reference and resolution, on the quality of the final assembly of the yeast strains W303 and SK1. Conclusions: We developed a cost-effective pipeline to generate chromosome-level sequence assemblies using only short-read sequencing data. Our pipeline combines the strengths of reference-guided and meta-assembly approaches. Our pipeline is available online at including a Docker image, as well as a Perl script, to help users install the IMAP package, including several prerequisite programs. Users can use IMAP to easily build the chromosome-level assembly for the genome of their interest. [ABSTRACT FROM AUTHOR]

A moisture separator reheater (MSR) system is installed between the high-pressure and low-pressure steam turbines in a nuclear power plant to increase the heat efficiency of the power plant. Erosion and corrosion of the MSR tubes have threatened the long-term operation of nuclear power plants. Thus a partial saturation eddy current testing (PSECT) method using a bobbin-type integrated Hall sensor array (BIHaS) was proposed in our previous study and it showed good results compared with a conventional PSECT. This paper presents a novel signal processing technique to improve detectability and measurability of electromagnetic testing method using a BIHaS through mitigating the inherent vibration signal noise between the BIHaS and ferritic stainless steel tubes. [ABSTRACT FROM AUTHOR]

The structure of a brake disc is coupled to the axle and rotates together with the wheel. A brake disc is a friction-type device that presses the pad on both sides of the disc. As more of its surface area becomes exposed to the air, it has better heat dissipation than the drum disc. It also has low fade phenomenon or vapor lock phenomenon despite frequent brake operation. In addition, it has the advantage of enabling precise control. But the braking force is obtained by the disc brake system by using the frictional force between the disc and the pad, and the pad is subjected to wear. For high-speed railway vehicles in particular, the wear and tear of the pad occurs more rapidly. This not only shortens the replacement cycle of the pad, but also has the disadvantage of reducing braking efficiency due to the rise in temperature during the initial braking process. Moreover, the heat that occurs will cause thermal distortion, which leads to the occurrence of a hot spot. This results in a reduction of the disc life. Looking comprehensively at the research trends to date it appears that thermal behavior analysis has only been performed thus far in terms of frictional thermal energy between the disc and the pad. Thermomechanical contact characteristics, on the other hand, have yet to be considered. The thermal behavior of the disc is analyzed experimentally using an infrared camera, and the causes of the hot band and hotspot are suggested. This analytical approach can shorten the analysis time, but it can only confirm the temperature distribution achieved by a single braking. While there is a significant difference in temperature distribution according to the actual braking, the analytical approach has solely focused on the hotspot generation mechanism. Therefore, in this study, the authors will use both a dynamometer and a thermographic camera to analyze BPs through a repetitive braking process, and will attempt to verify the cause of thermomechanical movement and BP occurrence through contact analysis of the disc and the pad. [ABSTRACT FROM AUTHOR]

One of the primary interests in the railway field is to improve speed as well as to secure the safety of railway vehicles at a high speed. In light of this, the demand for braking systems that offer improved performance and safety has also been growing consistently. The braking system is a critical element directly connected with safety. In order to secure reliability and establish the maintenance standard for the braking system, it is necessary to secure an accurate evaluation technology. As the braking disc of the braking system is very sensitive to safety and maintenance, a method to evaluate thermal cracking must be developed. Because the brake disc goes through a repeated process of heating and cooling due to the friction energy and the heat convection, respectively, in every braking action, it is subject to thermal fatigue. As well, the partial contact area caused by friction between disc and pad during the braking process results in thermal distortion, causing a hot band and a hot spot. This thermal distortion may also cause thermal cracking on the friction surface. The aim of this research was to find the cause of thermal cracking through a thermo-mechanical friction analysis of disc and pad, and to verify the analysis model through the dynamo machine. [ABSTRACT FROM AUTHOR]

This study aimed to dynamically analyze a simulated bimodal tram by determining the motion equations for computer-aided analysis with Newton-Euler equations of motion, which algebraically represent motion. We utilized the multi-body dynamics analysis program, MSC.Adams, to evaluate the equations of motion, running stability, curving performance, and ride comfort of the simulated bimodal tram in comparison with single fleet and double fleet trams. For the double fleet tram, the characteristic equation was deduced to control the all-wheel steering mechanism by independently moving all the wheels characterizing an articulated vehicle. Our study aimed to design a double fleet bimodal tram. We confirmed that domestic and international standards were satisfied via the design and analysis of the simulation. Steering control equations are the significant preliminary data for coupling device research and development for double fleet bimodal trams. [ABSTRACT FROM AUTHOR]

The histidine-rich Ca-binding protein (HRC) is located in the lumen of the sarcoplasmic reticulum (SR) and exhibits high-capacity Ca-binding properties. Overexpression of HRC in the heart resulted in impaired SR Ca uptake and depressed relaxation through its interaction with SERCA2a. However, the functional significance of HRC in overall regulation of calcium cycling and contractility is not currently well defined. To further elucidate the role of HRC in vivo under physiological and pathophysiological conditions, we generated and characterized HRC-knockout (KO) mice. The KO mice were morphologically and histologically normal compared to wild-type (WT) mice. At the cellular level, ablation of HRC resulted in significantly enhanced contractility, Ca transients, and maximal SR Ca uptake rates in the heart. However, after-contractions were developed in 50 % of HRC-KO cardiomyocytes, compared to 11 % in WT mice under stress conditions of high-frequency stimulation (5 Hz) and isoproterenol application. A parallel examination of the electrical activity revealed significant increases in the occurrence of Ca spontaneous SR Ca release and delayed afterdepolarizations with ISO in HRC-KO, compared to WT cells. The frequency of Ca sparks was also significantly higher in HRC-KO cells with ISO, consistent with the elevated SR Ca load in the KO cells. Furthermore, HRC-KO cardiomyocytes showed significantly deteriorated cell contractility and Ca-cycling caused possibly by depressed SERCA2a expression after transverse-aortic constriction (TAC). Also HRC-null mice exhibited severe cardiac hypertrophy, fibrosis, pulmonary edema and decreased survival after TAC. Our results indicate that ablation of HRC is associated with poorly regulated SR Ca-cycling, and severe pathology under pressure-overload stress, suggesting an essential role of HRC in maintaining the integrity of cardiac function. [ABSTRACT FROM AUTHOR]

Metabolic profiling of the fecal extracts of male mice was carried out to assess the effects of probiotics on colonic inflammation using 1H NMR spectroscopy coupled with multivariate data analysis. The control group (n = 5) was administered phosphate buffered saline for 14 days. Acute colitis was induced with dextran sulfate sodium (DSS) for 7 days following administration of phosphate buffered saline for 7 days (DSS-treated group, n = 5). LAB + DSS-treated group (n = 5) was administered lactic acid bacteria (LAB) daily for 7 days followed by treatment with DSS for 7 days to investigate protective effect of LAB against DSS-inducible colitis. Histological damage, myeloperoxidase activity, and malondialdehyde content of colon tissue were reduced, whereas colon length increased in LAB + DSS-treated mice compared to those in DSS-treated mice. DSS treatment was associated with fecal excretion of amino acids, short chain fatty acids, and nucleotides, revealing significant decreases of threonine, alanine, glutamate, glutamine, aspartate, lysine, glycine, butyrate, uracil, and hypoxanthine together with increases of monosaccharides, glucose, and trimethylamine in the feces of mice with DSS-induced colitis. Increased levels of acetate, butyrate, and glutamine and decreased levels of trimethylamine were found in the feces of LAB + DSS-treated mice compared to DSS-treated mice alone. The increased short chain fatty acids levels in the feces of mice fed with LAB indicate that the probiotics have protective effects against DSS-induced colitis via modulation of the gut microbiota. This work highlights the possibility for alternative approach of metabonomics in feces for assessing the probiotic effect in an animal model of inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

To investigate the mechanisms of the preventive activity of lactic acid bacteria in colitis, the inhibitory effect of Bifidobacterium longum HY8004, which potently inhibited lipid peroxidation in vitro, was examined in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitic mice. We measured the ability of lactic acid bacteria (LAB) to inhibit lipid peroxidation in vitro and to inhibit colitis outcomes, colon shortening, and myeloperoxidase activity in TNBS-induced colitis in C3H/HeN and C3H/HeJ mice. We also measured levels of the inflammatory markers interleukin (IL)-1β and tumor necrosis factor (TNF)-α and their transcription factor, NF-κB, in the colon by enzyme-linked immunosorbent assay and immunoblot analysis. Among the LAB tested, B. logum HY8004 most potently inhibited lipid peroxidation in vitro but did not inhibit TLR-4-linked NF-κB activation in HEK cells. Oral administration of HY8004 inhibited TNBS-induced colon shortening and myeloperoxidase activity in the colon of C3H/HeN and C3H/HeJ mice as well as IL-1β and TNF-α expression. B. longum HY8004 also inhibited TNBS-induced lipid peroxidation, TLR-4 expression, and NF-κB activation in the colon of C3H/HeN and C3H/HeJ mice. B. longum HY8004 can improve colitis via the inhibition of lipid peroxidation as well as NF-κB activation. [ABSTRACT FROM AUTHOR]

To evaluate the anti-colitic effect of lactic acid bacteria by cDNA microarray analysis, a lactic acid bacteria mixture (LM) consisting of Lactobacillus brevis HY7401, L. suntoryeus HY7801 and Bifidobacterium longum HY8004 was orally administered to dextran sulfate (DSS)-induced colitic mice and the expression profile of numerous genes was assessed. DSS treatment caused colitic outcomes such as inflammation and colon shortening. DSS also up-regulated the expression of inflammation-related genes: pro-inflammatory and chemotactic cytokines, including IL-1β, TNF-α, IL-6, CCL2, CCL4, CCL7, CCL24, CXCL1, CXCL2, CXCL5, CXCL9 and CXCL10, and their receptors CCR3 and CCR7, and other colitis-related genes such as COX-2, PAP, MMP family, S100a8, S100a9 and DEFA1. LM treatment inhibited the mRNA expression of inflammation-related and tissue remodeling genes induced by DSS as well as the colitic symptoms. LM inhibition for the DSS-induced expression of the representative inflammatory markers, IL-1β, TNF-α and COX-2, was supported by quantitative real-time polymerase chain reaction analysis. These findings suggest that LM ameliorates DSS-induced colitis by regulating inflammatory-related cytokines as well as tissue remodeling genes. [ABSTRACT FROM AUTHOR]

The Korean Railroad Research Institute (KRRI) developed the rubber-tired AGT system (Model: K-AGT) between 1999 and 2005. The K-AGT is a light rail transit system does not require a driver and generally operates on an elevated railroad for transporting passengers. Accidents caused by driverless vehicles can severely affect social confidence, safety and economy. Therefore, it is very important to minimize the occurrences of such faults, and to accurately perform detailed maintenance tasks and thoroughly investigate the cause of any repeated failures. This research develops the web-based reliability centered maintenance (RCM) system for the K-AGT train system. The framework of the RCM system is based on performing a failure mode and effects analyses (FMEA) procedure on all the sub-systems in the K-AGT system. Out of the devices that have a low reliability, the high failure ranked devices are included high on the list for performing the overall maintenance plans. Through registration of historical failure data and the reliability indexes, the results of the FMEA can be updated. Such a process is repeated continuously and can achieve very accurate predictions for device operational lifetimes and failure rates. Also, the RCM system is designed so that workers can refer to the expert system for the latest procedures to perform the required diagnosis and repair of any failure. The overall RCM system consists of a failure/task management system, a preventive maintenance system, an expert system, a material management system, and an approval system. This research describes the development of the preventive maintenance system and the expert system that have been produced because these are the main functions for the RCM system. [ABSTRACT FROM AUTHOR]

We have developed a reflection‐mode switchable subwavelength Bessel‐beam (BB) and Gaussian‐beam (GB) photoacoustic microscopy (PAM) system. To achieve both reflection‐mode and high resolution, we tightly attached a very small ultrasound transducer to an optical objective lens with numerical aperture of 1.0 and working distance of 2.5 mm. We used axicon and an achromatic doublet in our system to obtain the extended depth of field (DOF) of the BB. To compare the DOF performance achieved with our BB‐PAM system against GB‐PAM system, we designed our system so that the GB can be easily generated by simply removing the lenses. Using a 532 nm pulse laser, we achieved the lateral resolutions of 300 and 270 nm for BB‐PAM and GB‐PAM, respectively. The measured DOF of BB‐PAM was approximately 229 μm, which was about 7× better than that of GB‐PAM. We imaged the vasculature of a mouse ear using BB‐PAM and GB‐PAM and confirmed that the DOF of BB‐PAM is much better than the DOF of GB‐PAM. Thus, we believe that the high resolution achieved at the extended DOF by our system is very practical for wide range of biomedical research including red blood cell (RBC) migration in blood vessels at various depths and observation of cell migration or cell culture. Limited depth‐of‐field images (A, C) by Gaussian‐beam photoacoustic microscopy (PAM) vs extended depth‐of‐field images (B, D) by Bessel‐beam PAM. [ABSTRACT FROM AUTHOR]