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In this paper, we propose methods for the diagnosis of down conductor cables installed inside blades for the reliable operation of wind turbines. Utilizing the two synchronized drones equipped with X-ray devices to take X-ray images inside the blades, we propose deep learning methods for diagnosis based on X-ray images. The first method is the unsupervised deblurring method for blurry X-ray images that are generated by the drones. The key idea of the proposed method is to apply an image sharpening process to the latent space of the trained model using only blurry X-ray images. Through experiments using the X-ray images of blades, we show that the proposed method makes the outline of the down conductor cable clearer. As the second method, we propose an object detection-based method to provide fast and accurate object detection as the diagnosis. Given an X-ray image, we also propose a method to determine drone flight direction to enable drones to follow the down conductor cable. Through experiments, we show that our method has good performance in object detection (i.e., mAP of 98.21%) and classification (i.e., AUC of 0.9), and drone flight direction determination (i.e., AUC of 0.99).

This paper presents a novel multigeneration system that utilizes ammonia as the primary fuel for marine vessel applications. The system integrates and thermodynamically investigates various components, including solid oxide fuel cells (SOFC), gas turbines (GT), proton exchange membrane fuel cells (PEMFC), organic Rankine cycle (ORC), steam Rankine cycle (SRC), Kalina cycle (KC), and waste heat boiler (WHB). The primary objective of the integration strategy is to recover waste heat from the SOFC and harness the power generated by the PEMFC, resulting in improved thermal efficiency, reduced vessel startup time, and enhanced environmental sustainability. Mathematical models have been developed to facilitate the examination of the system’s thermodynamic performance. Comprehensive thermodynamic modeling employing energy and exergy analysis methods is employed to evaluate the effectiveness of both the proposed system and its subsystem. Moreover, the exergy destruction of all system components and integrated subsystems is quantified to provide a comprehensive understanding of their impact. The projected system exhibits an energy efficiency of 60.69% and an exergy efficiency of 57.50%. The waste heat recovery combined systems generate 1634.46 kW, accounting for 30.07% of the total power output of the integrated SOFC system. The performance of the system was analyzed through parametric studies, where different values of current density, distribution ratio (β) (from 0.1–0.4), and δ parameter (from 0–0.5) were examined. The findings revealed that increasing the current density led to a decrease in energy and exergy efficiency, despite an overall rise in the power output of the cogeneration system. Moreover, the waste heat boiler is capable of providing 1081 kg/h of superheated steam at 162 °C and 405 kPa to fulfill the heating requirements of marine lubricating oil, devices, and accommodation for seafarers on board the ship.

Tagetes erecta and Ocimum basilicum are medicinal plants that exhibit anti-inflammatory effects against various diseases. However, their individual and combined effects on osteoarthritis (OA) are unknown. Herein, we aimed to demonstrate the effects of T. erecta, O. basilicum, and their mixture, WGA-M001, on OA pathogenesis. The administration of total extracts of T. erecta and O. basilicum reduced cartilage degradation and inflammation without causing cytotoxicity. Although WGA-M001 contained lower concentrations of the individual extracts, it strongly inhibited the expression of pathogenic factors. In vivo OA studies also supported that WGA-M001 had protective effects against cartilage destruction at lower doses than those of T. erecta and O. basilicum. Moreover, its effects were stronger than those observed using Boswellia and Perna canaliculus. WGA-M001 effectively inhibited the interleukin (IL)-1β-induced nuclear factor kappa-light-chain-enhancer of the activated B cell (NF-κB) pathway and ERK phosphorylation. Furthermore, RNA-sequence analysis also showed that WGA-M001 decreased the expression of genes related to the IL-1β-induced NF-κB and ERK signaling pathways. Therefore, WGA-M001 is more effective than the single total extracts of T. erecta and O. basilicum in attenuating OA progression by regulating ERK and NF-κB signaling. Our results open new possibilities for WGA-M001 as a potential therapeutic agent for OA treatment.

Abstract A reliable forecasting model is required for photovoltaic (PV) power output because solar energy is highly volatile. Another driver for the need of a reliable forecasting model is concept drift, which means that the statistical properties of the data change over time. In this paper, an online forecasting method to handle concept drift is proposed. First, the problem of forecasting in batch learning is transformed into a forecasting in online learning setting. Then, an online learning algorithm is applied, which is good for handling concept drift. Through experiments using the real‐world data, it is shown that the method noticeably improves performance compared to the case where a trained model is used. Under various concept drift scenarios, the method improves performance by up to 87.3%. It is also shown that the re‐training method (a representative existing method) has several limitations. This method requires several issues to be solved, such as selection of a proper window size, and this is evident through results showing different performance under different settings. In contrast, the method shows a reliable and desirable performance under various concept drift scenarios and thus outperforms the re‐training method. The method improves performance by up to 79%.

Abstract Aims/Introduction Increased blood glucose or increased weight is often observed in patients who are prescribed sodium–glucose cotransporter 2 inhibitors (SGLT2i). The aim of this study was to determine in advance which patients, among those prescribed a SGLT2i, would be likely to have improved or worsened blood glucose levels and gain or loss of weight through the use of real‐world data‐based prescriptions. Materials and Methods After 3 months of dapagliflozin prescription, patients were divided into four groups: H(+)W(+) for improved glucose and weight loss; H(+)W(−) for improved blood glucose and weight gain; H(−)W(+) for worsened glucose and weight loss; and H(−)W(−) for worsened glucose and weight gain. Results The proportion of patients in the H(+)W(+) group was 53.5% (325/608 patients), H(+)W(−) was 19.7% (120/608), H(−)W(+) was 26.8% (114/608) and H(−)W(−) was 8.1% (49/608). The odds of proceeding to H(+)W(−) compared with H(+)W(+), which served as the reference, were 144% in baseline hemoglobin A1c (HbA1c) 7.0–8.0%, 233% in baseline HbA1c 8.0–9.0% and 359% in baseline HbA1c ≥ 9.0% (odds ratio 3.59, P

Demand response (DR) is a voluntary program that encourages related stakeholders, in this case electricity consumers, to cut down on usage during periods of high electricity load. One key to fully exploiting DR is to encourage residential customers to join the DR program. Unlike in the DR programs for commercial and industrial customers, for the successful operation of the residential DR program, several issues have to be addressed, one of which is to provide a group-level incentive to participating customers. In particular, the issue comes up when the incentive calculated for a group is not equal to the aggregated incentives for each customer (i.e., non-equal incentive problem). The non-equal incentive problem deteriorates the successful operation of residential DR by decreasing the motivation of DR operators and customers. We first prove the non-equal incentive problem through mathematical and experimental methods. We then propose the novel single group-based indirect incentive calculation method. The basic idea of our approach is to indirectly calculate the incentive for each customer not using the customer’s data but using the data of other customers of the same DR group. Through experiments involving the electricity usage data of 42,193 households and the real DR events in Korea, we show that our method solves the non-equal incentive problem in most cases. Furthermore, our method improves the accuracy of the baseline estimation (used for calculating the contribution).

In realizing unsupervised pixel-precise anomaly localization by utilizing a generative model, a reference image must be generated (for comparison with an input image) by transforming abnormal patterns of an input image, if any, into normal patterns. In this study, a patch-level operation with adaptive patch control is proposed to improve anomaly localization by generating a better reference image. As a way to exploit a generative model, we divide an image into non-overlapped patches of the same size, generate patch-level reference images, and stitch the patch-level reference images into a single reference image. We then conduct anomaly localization by comparing an input image with the stitched, reconstructed image. To effectively apply the patch-level operation, we propose adaptive patch control to determine the number of non-overlapped patches to be applied. For this, we synthesize defective images using normal images and examine how well the candidate methods with different numbers of patches remove the synthesized defects. In the same way, we utilize adaptive patch control to select a promising model among the candidate generative models. Based on experiments conducted using the MVTec Anomaly Detection dataset, we demonstrate that our method outperforms previous existing methods. Under a real-world scenario, our method shows ROC AUC of 0.926, in contrast to the best value of 0.893 from existing studies. Furthermore, we prove the feasibility of the adaptive patch control by showing that the removal of the synthesized defects and the anomaly localization for real defective images are highly correlated.

BackgroundSome patients admitted to hospitals for glycemic control experience hypoglycemia despite regular meals and despite adhering to standard blood glucose control protocols. Different factors can have a negative impact on blood glucose control and prognosis after discharge. This study investigated risk factors for hypoglycemia and its effects on glycemic control during the hospitalization of patients in the general ward.MethodsThis retrospective study included patients who were admitted between 2009 and 2018. Patients were provided regular meals at fixed times according to ideal body weights during hospitalization. We categorized the patients into two groups: those with and those without hypoglycemia during hospitalization.ResultsOf the 3,031 patients, 379 experienced at least one episode of hypoglycemia during hospitalization (HYPO group). Hypoglycemia occurred more frequently particularly in cases of premixed insulin therapy. Compared with the control group, the HYPO group was older (61.0±16.8 years vs. 59.1±16.5 years, P=0.035), with more females (60.4% vs. 49.6%, P

Background/Aims The purpose of the study is to investigate the associations between sarcopenia and health-related quality of life in elderly men and women in Korea. Methods In a cross-sectional study using data from 2008 to 2011 Korean National Health and Nutrition Examination Survey, 4,937 adults aged 60 years and older who underwent a dual-energy X-ray absorptiometry scan were included in the study. Sarcopenia is defined as an appendicular skeletal muscle index of two standard deviations or more below the mean for young, healthy reference populations. The health-related quality of life was measured using the EuroQol-5 dimension questionnaire. Results The overall prevalence of sarcopenia was 6.6% in these Korean people over the age of 60 years: 11.1% for men and 3.2% for women. Sarcopenic men tended to have lower income, lower physical activity, lower body mass index, and smaller waist circumference compared with nonsarcopenic men. Sarcopenic women tended to have higher body mass index and larger waist circumference compared with nonsarcopenic women. Sarcopenic men showed higher impairments in mobility, self-care, usual activities, and pain/discomfort compared with nonsarcopenic men. Women with sarcopenia also showed higher impairments in mobility, self-care, usual activities, and anxiety/depression compared with nonsarcopenic women. Sarcopenia showed an association with impairments in selfcare for men, and with impairments in self-care, usual activities, and anxiety/depression for women, after adjusting for other confounding factors. Conclusions There is a significant association between sarcopenia and impaired health-related quality of life in this elderly Korean population, and these results differ between men and women.

Introduction. In spite of the established importance of detecting angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker- (ARB-) induced hyperkalemia, there have not been many studies on the time of its occurrence. Methods. We retrospectively analyzed electronic medical records to determine the onset time and incidence rate of hyperkalemia (serum potassium>5.5 mEq/L or 6.0 mEq/L) among hospitalized patients newly started on a 15-day ACEI or ARB therapy. Results. Among 3101 hospitalized patients, hyperkalemia incidence was 0.5%–0.9% and 0.8%–2.1% in the ACEI and ARB groups, respectively. However, it was not significantly different among different ARB types. Hyperkalemia’s onset was distributed throughout 15 days, without any trend. Hyperkalemia incidence was 7.3 and 35.1 times higher at 5.5 mEq/L (hazard ratio HR=7.31, 95%confidence interval CI=4.19–12.76, p

Introduction. Severe hypoglycemia can be life-threatening; therefore, it is important to identify the characteristics of the hypoglycemic patients. The aim of this study is to analyze the type and characteristics of diabetic patients with hypoglycemia who visited an emergency room. Methods. We included diabetic patients with hypoglycemia who visited the emergency room of St. Mary’s Hospital in Seoul from January 2009 to August 2018 in the study. Hypo_S group patients visited the emergency room once whereas Hypo_M group patients visited twice or more. We also compared the incidence of cardiovascular disease between the groups within 5 years after hypoglycemia. Results. A total of 843 patients were included in this study, with a mean age of 71±14 years and average glycated hemoglobin (HbA1c) level of 6.7±1.4%. For patients with hypoglycemia, lower body mass index, lower HbA1c, shorter diabetes duration, and lower glomerular filtration rate have a statistically significant relationship with patient characteristics in the emergency room group (all p

International ships carrying liquefied fuel are strongly recommended to install vent masts to control the pressure of cargo tanks in the event of an emergency. However, the gas emitted from a vent mast may be hazardous for the crew of the ship. In the present study, the volume and length of the flammable zone (FZ) created by the emitted gas above the ship was examined. Various scenarios comprising four parameters, namely, relative wind speed, arrangement of vent masts, combination of emissions among four vent masts, and direction of emission from the vent-mast outlet were considered. The results showed that the convection acts on the volume and length of an FZ. The volume of an FZ increases when there is a reduction in convection reaching the FZ and when strong convection brings hydrogen from a nearby FZ. The length of the FZ is also related to convection. An FZ is elongated if the center of a vortex is located inside the FZ, because this vortex traps hydrogen inside the FZ. The length of an FZ decreases if the center of the vortex is located outside the FZ, as such a vortex brings more fresh air into the FZ.

Purpose Defensin alpha 6 (DEFA6) is cationic short peptide with known functional activities in innate antimicrobial immunity. DEFA6 is also highly expressed in colorectal cancer tissue. The mechanism and function of DEFA6 have not been reported how to play a significant role in carcinogenesis and cancer progression. The aim of this study was to evaluate the protumorigenic functions of DEFA6 in the colorectal cancer cell line and the clinical significance of DEFA6 expression in colorectal cancer patients. Methods DEFA6 expression was investigated by immunohistochemistry in 151 cases of colorectal cancer tissue and the association of DEFA6 expression was correlated with patient's cancer charecteristics. Results Immunohistochemistry analysis showed that the DEFA6 protein was expressed higher in advanced cancer group (high T stage, patients with lymph node metastasis, patients with vascular invasion) than early cancer group (low T stage, patients without lymph node metastasis, patients without vascular invasion) (P=0.007/0.032/0.047). Conclusion As patient's survival usually depends on migration and invasion of the cancer cell, the high expression of DEFA6 in colorectal cancer cell is associated with patient's cancer charecteristics and could be a biomarker for colorectal cancer. The future study about characterization of DEFA6 will clarify its specific role in oncogenesis and its therapeutic potential.

Liquefied natural gas (LNG) is attracting increasing attention as an alternative fuel in the maritime sector, as it can reduce harmful emissions for compliance with stricter environmental regulations. Owing to this environmental advantage, the number of ships using LNG as a fuel is increasing; thus, the demand for ship-to-ship LNG bunkering is increasing. One of the challenges of ship-to-ship LNG bunkering is boil-off gas (BOG) management, as it is more difficult than normal BOG management. This study analyzed the influences of the parameters on vapor generation, including the temperature difference between the bunker tank and receiving tank, bunkering flow rate, insulation performance, and compositions. A model based on a typical bunkering system was established, and a dynamic simulation was conducted using a commercial process simulator, Aspen HYSYS. The results indicated that as the initial temperature of the receiving tank increased, the amount of vapor return increased proportionally. In addition, increasing the bunkering flow rate decreased the amount of heat entering through the pipes and tanks; however, the heat dissipated by the pump shaft power increased. Different LNG compositions in the bunker tank led to changes in the initial pressure of the bunker tank, influencing the vapor return and vapor generation in the receiving tank. Through a parametric study, it was found that the pressure of the tank is the most important factor in terms of vapor return and vapor generation. As such, a pressure control method was proposed for the tank, so as to reduce vapor generation and vapor return. With pressure control, the total amount of vapor return to the bunker tanks is reduced from 7392 to 3317 kg. The net vapor generation in the receiving tank is reduced by up to 4047 kg and the net vapor generation in the overall system is reduced by 16.2%.

Justicia procumbens L. is known across Korea, India, China, and Taiwan as a remedy against fever, cough, sore throat, and cirrhosis of ascites. J. procumbens provides the raw material for a candidate anti-asthma drug (DW2008S) currently completing phase I clinical trials sponsored by Dong Wha Pharmaceutical Company. HPLC-DAD was used to quantify phytochemical constituents of J. procumbens, and HPLC and 1H-NMR results were assessed by multivariate analysis. This is the first time a comparative study using HPLC-DAD and NMR fingerprints has been applied to identify chemical differences between wild and cultivated J. procumbens. The amount of justicidin B as the marker compound was higher in cultivated samples (0.80 ± 0.25 mg/g) than in wild ones (0.63 ± 0.30 mg/g). Orthogonal partial least squares discriminant analysis (OPLS-DA) from HPLC and NMR data revealed that there were clear differences between wild and cultivated types and identified five secondary metabolites, which could help distinguish between wild and cultivated plants. Among these five lignans, diphyllin showed the most potent discrimination between two types and was significantly detected higher in cultivated ones than in wild ones. A combination of 1H-NMR and HPLC-DAD analysis is effective for J. procumbens standardization and metabolomics studies.

This study performs energetic and exergetic comparisons between the steam methane reforming and steam methanol reforming technologies combined with HT-PEMFC and a carbon capture/liquefaction system for use in hydrogen-fueled ships. The required space for the primary fuel and captured/liquefied CO2 and the fuel cost have also been investigated to find the more advantageous system for ship application. For the comparison, the steam methane reforming-based system fed by LNG and the steam methanol reforming-based system fed by methanol have been modeled in an Aspen HYSYS environment. All the simulations have been conducted at a fixed Wnet, electrical (475 kW) to meet the average shaft power of the reference ship. Results show that at the base condition, the energy and exergy efficiencies of the methanol-based system are 7.99% and 1.89% higher than those of the methane-based system, respectively. The cogeneration efficiency of the methane-based system is 7.13% higher than that of the methanol-based system. The comparison of space for fuel and CO2 storage reveals that the methanol-based system requires a space 1.1 times larger than that of the methane-based system for the total voyage time, although the methanol-based system has higher electrical efficiency. In addition, the methanol-based system has a fuel cost 2.2 times higher than that of the methane-based system to generate 475 kW net of electricity for the total voyage time.

Purpose: Neuropilin-2 is expressed by venous and lymphatic endothelial cells and can bind the lymphangiogenesis-associated ligand vascular endothelial growth factor (VEGF)-C and D. Recently, neuropilin-2 was shown to play a role in lymph node metastasis and cancer promotion. The aim of this study was to determine the clinical relevance of neuropilin-2 expression in colorectal carcinomas. Methods: Immunohistochemical analysis of neuropilin-2 expression of 350 colorectal cancer samples was evaluated using tissue microarray. The relationship between neuropilin-2 expression and other clinicopathological variables were analyzed in colorectal carcinomas. To clarify the role of neuropilin-2 in colorectal cancer lymphangiogenesis, its expression was examined with VEGF-C, VEGF-D, and VEGF receptor 3 expression of the colorectal carcinomas. Results: Neuropilin-2 was detected in 176 of 350 colorectal carcinomas (50.3%). Overexpression of neuropilin-2 was correlated with lymph node metastasis (P=0.041) and VEGF-D expression (P=0.020), but was not correlated with TNM (tumor, node, metastasis) stage, other lymphangiogenic factor expression and survival colorectal cancer patients. Conclusion: Neuropilin-2 expression was correlated with lymph node metastasis and VEGF-D expression in colorectal carcinomas. Our results suggest a possible role of neuropilin-2 in lymphangiogenesis and cancer progression in colorectal carcinomas.

Hypoxia in the tumor microenvironment is the leading factor in angiogenesis. Angiogenesis can be identified by dynamic contrast-enhanced breast MRI (DCE MRI). Here we investigate the relationship between perfusion parameters on DCE MRI and angiogenic and prognostic factors in patients with invasive ductal carcinoma (IDC). Perfusion parameters (Ktrans, kep and ve) of 81 IDC were obtained using histogram analysis. Twenty-fifth, 50th and 75th percentile values were calculated and were analyzed for association with microvessel density (MVD), vascular endothelial growth factor (VEGF) and conventional prognostic factors. Correlation between MVD and ve50 was positive (r = 0.33). Ktrans50 was higher in tumors larger than 2 cm than in tumors smaller than 2 cm. In multivariate analysis, Ktrans50 was affected by tumor size and MVD with 12.8% explanation. There was significant association between Ktrans50 and tumor size and MVD. Therefore we conclude that DCE MRI perfusion parameters are potential imaging biomarkers for prediction of tumor angiogenesis and aggressiveness.