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An evaluation was conducted to assess the surf-riding/broaching vulnerability of a 9.77-ton fishing boat by applying the regulations for stability assessment proposed by IMO (International Maritime Organization). Both Level 1 and 2 assessments were conducted and included a range of parameters along with the IMO second-generation intact stability criteria. In particular, it is considered three cases of wave forces acting on the hull for the surf-riding/broaching vulnerability Level 2 assessment calculations: (a) Froude-Krylov force (fFK) + 0.1M, (b) Froude-Krylov force (fFK) + added mass of the ship (Ma), and (c) Froude-Krylov force (fFK) + diffraction force (fD) + added mass of the ship (Ma). Previous results provided by IMO correspond to (b), and accurate calculation of wave forces helps to obtain more design margins. The design margins are high in the order (a) < (b) < (c), as described in the classification criteria. However, in certain cases, the assessment results may not differ significantly, so the hydrodynamic approximation assumption may be useful.

Expanding waste-to-energy (WtE) facilities is difficult, and with tightening incineration regulations, improvements in WtE facility operations are required to dispose of waste that is increasing by an average of 4.8% annually. To achieve this, an intelligent combustion control (ICC) system was studied using digital technologies such as the Internet of Things and artificial intelligence to improve the operation of WtE facilities. The ICC system in this study is composed of three modules: perception, decision, and control. Perception: collecting and visualizing digital data on the operating status of WtE facilities; Decision: using AI to propose optimal operation methods; Control: automatically controlling the WtE facility according to the AI-suggested optimization methods. The ICC system was applied to the “G” WtE facility, a solid waste WtE facility operating in Gyeonggi province, Republic of Korea, and the digital data collected over six months showed high quality, with low delay and a data loss rate of only 0.12%. Additionally, in January 2024, the ICC system was used to automatically control the second forced draft fan and induced draft fan over a four-day period. As a result, the incinerator flue gas temperature decreased by 0.66%, steam flow rate improved by 2.41%, power generation increased by 3.09%, CO emissions were reduced by 60.72%, and NOx emissions decreased by 7.33%. Future research will expand the ICC system to include the automatic control of the first forced draft fan and the operation time of the stoker.

Visceral artery pseudoaneurysms is a known vascular complication of pancreatitis that can lead to life-threatening hemorrhages with a high mortality rate if left untreated. We present a case of ruptured gastroduodenal artery pseudoaneurysm in a 68-year-old male with acute pancreatitis presenting with fatal gastrointestinal and retroperitoneal bleeding that was successfully managed with endovascular coil embolization of the involved vasculature. Patients with hemorrhagic pancreatitis or those presenting with unexplained retroperitoneal or gastrointestinal bleeding in the setting of pancreatitis with an unexplained drop in hematocrit or sudden expansion of pancreatic fluid collection should be screened in a timely manner for pseudoaneurysm using CT angiogram of the abdomen, which is the gold standard imaging modality to identify pseudoaneurysms. Once pseudoaneurysm is diagnosed, it should be treated immediately. Endovascular treatment options are now favored over surgical options in most cases.

Breast cancers metastasize most commonly to the bone, brain, liver, and lungs, but rarely to the gastrointestinal tract. Although metastatic breast carcinomas in the stomach can be confused with primary gastric cancers due to their nonspecific presentation and rare incidence, it is important to differentiate the two since the treatment is different. Clinical suspicion is imperative for a prompt endoscopic evaluation and a definitive diagnosis that will lead to appropriate treatment. Therefore, it is important for clinicians to be aware of the possibility of gastric metastasis of breast cancers, especially in those with a history of invasive lobular breast carcinoma and a new onset of gastrointestinal symptoms.

Abstract Recently, low-cost sensors (LCSs) have been widely used in monitoring particulate matter (PM) mass concentrations. Maintaining the accuracy of the sensors is important and requires rigorous calibration and performance evaluation. In this study, two commercial LCSs, Plantower PMS3003 and Plantower PMS7003, were evaluated in the laboratory and in the field using a reference-grade PM monitor (GRIMM 11-D). Laboratory evaluation was conducted with polystyrene latex (PSL) particles in a 1 m3 chamber at 20°C with a relative humidity of 20%. Each LCS indicated higher mass concentrations than GRIMM 11-D for small-sized PSL particles (0.56 µm); however, the LCSs indicated lower mass concentrations than GRIMM 11-D for PSL particles larger than 0.56 µm. In addition, the difference in mass concentrations between the LCS and GRIMM 11-D became higher with particle sizes greater than 0.56 µm. Nonetheless, a high correlation (R2 > 0.9) between each LCS and GRIMM 11-D was obtained. Field evaluation was conducted at Yonsei University (Seoul, South Korea) from February 12 to March 31, 2022. The LCSs showed generally higher PM mass concentrations than GRIMM 11-D; however, some data points of the LCSs revealed different trends. We observed that outdoor PM10/PM2.5 and relative humidity had notable impacts on the LCS data; in addition, LCS sensitivity depended on whether the PM concentration was low or high. Based on these observations, regression-based calibration models were constructed using the selected independent variables (outdoor PM10/PM2.5 and relative humidity) after dividing the PM concentration into low and high sections. Consequently, the accuracy of the LCSs was significantly enhanced. Therefore, using LCSs with the calibration models can replace the use of expensive reference PM monitors, resulting in cost savings.

Abstract Antimicrobial peptides (AMPs) are promising therapeutics in the fight against multidrug‐resistant bacteria. As a mimic of AMPs, peptoids with N‐substituted glycine backbone have been utilized for antimicrobials with resistance against proteolytic degradation. Antimicrobial peptoids are known to kill bacteria by membrane disruption; however, the nonspecific aggregation of intracellular contents is also suggested as an important bactericidal mechanism. Here,structure‐activity relationship (SAR) of a library of indole side chain‐containing peptoids resulting in peptoid 29 as a hit compound is investigated. Then, quantitative morphological analyses of live bacteria treated with AMPs and peptoid 29 in a label‐free manner using optical diffraction tomography (ODT) are performed. It is unambiguously demonstrated that both membrane disruption and intracellular biomass flocculation are primary mechanisms of bacterial killing by monitoring real‐time morphological changes of bacteria. These multitarget mechanisms and rapid action can be a merit for the discovery of a resistance‐breaking novel antibiotic drug.

In this work, the effects of carbon nanotubes and an amphoteric surfactant, namely lauryl betaine, on the absorbance, contact angle, surface tension, and thermal conductivity of DW were experimentally investigated. The concentration of the carbon nanotubes was 0.5 wt% and that of lauryl betaine was 100, 500, and 1000 ppm in distilled water. From the absorbance measurement results, the addition of lauryl betaine could increase the absorbance in the wavelength range of UV and visible rays (200~1000 nm). In addition, the higher the surfactant concentration, the higher the dispersibility. The contact angle of the distilled water showed a monotonic decreasing trend with an increase in the surfactant blending ratio, while there were no significant changes in that of the carbon nanotube nanofluid. Analogous behaviors were observed in the surface tension measurements. The surface tension of the distilled water dramatically decreased with an increase in the surfactant blending ratio. The highest decrement was 46.05% at the surfactant concentration of 1000 ppm. In contrast, there were no significant changes in the case of the carbon nanotube nanofluid. Adding 0.5 wt% of the carbon nanotubes to distilled water could substantially enhance the thermal conductivity up to approximately 3%. The degradation effect of the amphoteric surfactant on the thermal conductivity of the fluids was observed in both distilled water and nanofluids.

With increasingly stringent emissions legislation, such as that stipulated by the International Maritime Organization, for nitrogen oxide emission reduction in marine diesel engines, the imperative of curtailing nitrogen oxide emissions from marine diesel engines is intensifying. Consequently, the significance of aftertreatment technologies, including diesel particulate filters (DPFs) and selective catalytic reduction (SCR), is poised to grow substantially. In particular, a redesign is required to reduce the size of DPF and SCR systems for application in small ships. In this study, we varied the shape of the filters in DPF and SCR systems, aiming to achieve a distinct flow pattern and enable overall miniaturization. The performance metrics, including the nitric oxide (NO) reduction rate, NH3 slip rate, and pressure drop, of the redesigned models were compared with those of the conventional model. Computational fluid dynamics simulations were used to compare the performance of the redesigned model with that of the conventional model in terms of NO reduction and pressure drop. The redesigned system achieved a NO reduction rate of 6.9% below that of the conventional system, offering additional noteworthy benefits such as a 50% reduction in both pressure and overall length.

Background: Right ventricular (RV) dysfunction in acute COVID-19 was reported to be associated with poor prognosis. We studied the association between parameters of RV dysfunction and in-hospital mortality during the surges caused by different SARS-CoV-2 variants. Methods: In a retrospective single-center study, we enrolled 648 consecutive patients hospitalized with COVID-19 [66 (10 %) hospitalized during the alpha variant surge, 433 (67 %) during the delta variant surge, and 149 (23 %), during the omicron variant surge]. Patients were reported from a hospital with an underreported population of mostly African American and Hispanic patients. Patients were followed for a median of 11 days during which in-hospital death occurred in 155 (24 %) patients [Alpha wave: 25 (38 %), Delta Wave: 112 (26 %), Omicron wave: 18 (12 %), p

Lubricant (or oil)-impregnated porous surface has been considered as a promising surface treatment to realize multifunctionality. In this study, silicone oil was impregnated into a hard porous oxide layer created by the plasma electrolytic oxidation (PEO) of aluminum (Al) alloys. The monolayer of polydimethylsiloxane (PDMS) from silicone oil is formed on a porous oxide layer; thus, a water-repellent slippery oil-impregnated surface is realized on Al alloy, showing a low contact angle hysteresis of less than 5°. This water repellency significantly enhanced the corrosion resistance by more than four orders of magnitude compared to that of the PEO-treated Al alloy without silicone oil impregnation. The silicone oil within the porous oxide layer also provides a lubricating effect to improve wear resistance by reducing friction coefficients from ~0.6 to ~0.1. In addition, because the PDMS monolayer can be restored by frictional heat, the water-repellent surface is tolerant to physical damage to the oxide surface. Hence, the results of this fundamental study provide a new approach for the post-treatment of PEO for Al alloys.

In this paper, the evaluation procedure for Level 1, Level 2A, and Level 2B for the parametric roll among the five modes of the IMO second generation stability criteria was explained in detail. Parametric roll mode evaluation was performed using the design data of a medium-sized 13K chemical tanker instead of a well-known container ship. As a result of the Level 1 evaluation, δGM1/GM was smaller than the standard value, thus satisfying the first criterion, but the second criterion value was smaller than 1, so it was found that the Level 1 criterion was not satisfied. Subsequently, in the Level 2A evaluation, the weighted sum value was larger than the standard value under the ship speed and given wave conditions, so it was also not satisfied. In particular, the process of numerical analysis in the time domain was described through the equation of motion when estimating the maximum roll angle of a ship in the Level 2B evaluation, which was not detailed in previous studies. The calculation result was larger than the standard value, so it was not satisfied, and consequently, the 13K chemical tanker did not satisfy Level 1, Level 2A, and 2B.

One of the fundamental technologies for unmanned combat aerial vehicles and combat simulators is behavior optimization, which finds a behavior that maximizes the probability of winning a battle. With the advent of military science, combat logs became available, allowing machine learning algorithms to be used for the behavior optimization. Due to implicit attributes such as the experience of an operator that are not explicitly presented in log data, existing methods for behavior optimization have limitations in performance improvement. Furthermore, specific behaviors occur with low frequency, resulting in a dataset with imbalanced and empty values. Therefore, we apply a matrix factorization (MF) method, which is one of latent factor models and known for sophisticated imputation of empty values, to the behavior optimization problem of unmanned combat aerial vehicles. A situation-behavior matrix, whose elements are ratings indicating the optimality of behaviors in situations, is defined to implement the MF based method. Experiments for performance comparison were conducted on combat logs, in which the proposed method yielded satisfactory results.

Usually, the level of asymmetry between the left and right brain caused by the difference between left and right brain functions is seen in an EEG analysis, as we see in the literature. A prerequisite for optimizing brain function is appropriate symmetry between the left brain and the right brain. In this paper, we developed a neurofeedback system to improve emotional disorders, such as anxiety and depression, and to optimize the brain function. Our experiment confirmed an enhancement in the symmetry of left/right brain activities and EEGs in each training section. A comparison of the results for the first and third weeks of the experiment showed a considerable increase in alpha and beta waves, and we found that the symmetry between the left and right brain activities was improved. The system might be applied in various fields, including education programs improving concentration for children and medical treatments to improve depression and insomnia for adults.

Laser powder bed fusion (LPBF) is a promising additive-manufacturing process for metallic materials. It has the advantage of flexibility in product design, such that various mechanical parts can be fabricated. However, because metal parts are built-up in a layer-by-layer manner, the material fabricated by LPBF has an anisotropic microstructure, which is important for the design of materials. In this study, the corrosion resistance of 18Ni300 maraging steel (MS) fabricated by LPBF was explored considering the building direction. Furthermore, the effects of heat treatment and aging on the microstructure and corrosion resistance were investigated. Sub-grain cells formed by rapid cooling in LPBF improve the corrosion resistance of MS. As a result, the as-built MS has the highest corrosion resistance. However, the sub-grain cells are eliminated by heat treatment or aging, which causes the deterioration of corrosion resistance. In the case of 18Ni300 MS, the cylindrical sub-grain cells are formed and aligned along the heat dissipation direction, which is similar to the building direction; thus, a significant anisotropy in corrosion resistance is found in the as-built MS. However, such anisotropy in corrosion resistance is diminished by heat treatment and aging, which eliminates the sub-grain cells.

As unmanned aerial vehicles have become popular, the number of accidents caused by an operator’s inattention have increased. To prevent such accidents, the operator should maintain an attention status. However, limited research has been conducted on the brain-computer interface (BCI)-based system with an alerting module for the operator’s attention recovery of unmanned aerial vehicles. Therefore, we introduce a detection and alerting system that prevents an unmanned aerial vehicle operator from falling into inattention status by using the operator’s electroencephalogram signal. The proposed system consists of the following three components: a signal processing module, which collects and preprocesses an electroencephalogram signal of an operator, an inattention detection module, which determines whether an inattention status occurred based on the preprocessed signal, and, lastly, an alert providing module that presents stimulus to an operator when inattention is detected. As a result of evaluating the performance with a real-world dataset, it was shown that the proposed system successfully contributed to the recovery of operator attention in the evaluating dataset, although statistical significance could not be established due to the small number of subjects.

In this paper, a framework for a simulation approach to develop a formal representation of control and analysis of human-involved computer integrated manufacturing systems (Hi-CIM) is presented. Important properties of a human material handler within manufacturing systems are discussed and human tasks and errors are identified to build a simulation model. Based on the number of locations where a human operator is required to move to complete a task, material handling tasks are classified into two sets which include an on-the-spot task set and an around-the-system task set. For human errors associated with the task sets, a location error set and an orientation error set are defined. These task sets and error types provide a framework for developing a simulation model of a human material handling task-performing process. To represent the model, a colored Petri net model is used because it provides a good graphical and analytical representation of a system. Human tasks and error types are represented using color tokens. A simulation model of the system can be implemented based on the proposed colored Petri Net model.

For patients who have a senile mental disorder such as dementia, the quantity of exercise and amount of sunlight are an important clue for doses and treatment. Therefore, monitoring daily health information is necessary for patients’ safety and health. A portable and wearable sensor device and server configuration for monitoring data are needed to provide these services for patients. A watch-type device (smart watch) that patients wear and a server system are developed in this paper. The smart watch developed includes a GPS, accelerometer, and illumination sensor, and can obtain real time health information by measuring the position of patients, quantity of exercise, and amount of sunlight. The server system includes the sensor data analysis algorithm and web server used by the doctor and protector to monitor the sensor data acquired from the smart watch. The proposed data analysis algorithm acquires the exercise information and detects the step count in patients’ motion acquired from the acceleration sensor and verifies the three cases of fast pace, slow pace, and walking pace, showing 96% of the experimental results. If developed and the u-Healthcare System for dementia patients is applied, higher quality medical services can be provided to patients.

The International Maritime Organization (IMO) has been discussing technical issues by dividing the second-generation intact stability criteria for ships into five types. In this paper, we paid attention to the dead ship condition and introduced the process for the assessment of Levels 1 and 2 in detail. Dead ship condition refers to a case where a large angle of rolling motion occurs due to waves incident on the side of the ship's hull after the ship's engine has failed. Basically, in the dead ship condition, if the Level 1 criterion for analysis related to the GZ curve is not satisfied, an evaluation is performed against the Level 2 criterion considering the hydrodynamics of waves. The method for the effective wave slope function required to obtain the spectrum of the effective relative roll angle, which is the most important factor in the calculation of Level 2, was implemented. In particular, unlike existing ship types in terms of various experiences, this study performed stability evaluation using special ship data of a 5000HP tug boat and obtained results that satisfied both Level 1 and 2 standards. Through this example of dead ship condition evaluation for a tug boat, we aim to ensure the expansion of IMO second-generation intact stability evaluation targets for various types of ships. [ABSTRACT FROM AUTHOR]

An 8-year-old, 6.5 kg, neutered female Shih-Tzu dog was presented for surgical resection of a mediastinal mass. A median sternotomy and left cranial lung lobectomy were performed. Intraoperatively, with the patient under general anaesthesia, a bilateral transversus thoracis plane (TTP) block was performed by injecting 0.5% bupivacaine (0.2 ml/kg) per side using real-time ultrasound guidance. After surgery, indwelling catheters for repeated bolus injections of bupivacaine in TTP were placed as follows: the fifth sternebra was palpated in dorsal recumbency, and the transducer was placed in the longitudinal plane lateral to the sternal border. A 16 gauge over-the-needle catheter was inserted caudo-cranially using an in-plane technique and located in the TTP. An intermittent bolus of bupivacaine (0.1 ml/kg) per side was injected via the indwelling catheter every 8 h for 3 days, with a constant rate infusion of an intravenous fentanyl (1 μg/kg/h) and ketamine (0.12 mg/kg/h) combination. Post-operative pain was evaluated using the Glasgow composite measure pain scale and the score was 4--5/24 on the day of surgery and gradually decreased over time. Additional rescue analgesia was not required. Repeated boluses of bupivacaine for a continuous bilateral TTP block may be a useful adjuvant for perioperative pain management strategies, including median sternotomy, in dogs. [ABSTRACT FROM AUTHOR]