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Background: Job stress was found to directly increase the likelihood of accidents and indirectly increase the likelihood of accidents by lowering the safety atmosphere. Job stress has a significant impact on the safety environment, and job satisfaction is effective in reducing accident rates. Accordingly, we sought to investigate the correlation between safety level, job stress, and job satisfaction in small businesses with a high risk of industrial accidents. Additionally, we aim to investigate factors that may affect job stress, job satisfaction, and safety levels. Methods: This study was conducted on 230 workers in small businesses in Korea. First, hierarchical regression analysis was conducted using SPSS software, and anova analysis was used to investigate significant variables. Finally, the relationships between variables were investigated using structural equation modeling (SEM). Results: The analysis results showed that safety level and job stress had a negative correlation with a coefficient of −0.8. Safety level and job satisfaction had a correlation with a coefficient of 0.2. Job satisfaction and job stress had a negative correlation with a coefficient of −0.7. This shows that when job stress is high, there is a negative correlation between job satisfaction and safety level. In addition, 4 general characteristics items and 3 job characteristics items showed a correlation with job stress. 2 general characteristics items and 8 job characteristics items showed a correlation with job satisfaction. 4 general characteristics items and 11 job characteristics items showed a correlation with safety level. Conclusion: Small businesses' job stress, safety level, and job satisfaction showed a significant correlation. In addition, the relationship between the variables affecting them was significant. In order to reduce the occurrence of accidents among workers in small businesses, control of factors and efforts to reduce job stress are necessary.

Abstract Hexagonal boron nitride (h‐BN) is a key ingredient for various 2D van der Waals heterostructure devices, but the exact role of h‐BN encapsulation in relation to the internal defects of 2D semiconductors remains unclear. Here, it is reported that h‐BN encapsulation greatly removes the defect‐related gap states by stabilizing the chemisorbed oxygen molecules onto the defects of monolayer WS2 crystals. Electron energy loss spectroscopy (EELS) combined with theoretical analysis clearly confirms that the oxygen molecules are chemisorbed onto the defects of WS2 crystals and are fixated by h‐BN encapsulation, with excluding a possibility of oxygen molecules trapped in bubbles or wrinkles formed at the interface between WS2 and h‐BN. Optical spectroscopic studies show that h‐BN encapsulation prevents the desorption of oxygen molecules over various excitation and ambient conditions, resulting in a greatly lowered and stabilized free electron density in monolayer WS2 crystals. This suppresses the exciton annihilation processes by two orders of magnitude compared to that of bare WS2. Furthermore, the valley polarization becomes robust against the various excitation and ambient conditions in the h‐BN encapsulated WS2 crystals.

ROV operators often encounter challenges with orientation awareness while operating underwater, primarily due to relying solely on 2D camera feeds to manually control the ROV robot arm. This limitation in underwater visibility and orientation awareness, as observed among Malaysian ROV operators, can compromise the accuracy of arm placement, and pose a risk of tool damage if not handle with care. To address this, a 3D orientation monitoring system for ROVs has been developed, leveraging measurement sensors with nine degrees of freedom (DOF). These sensors capture crucial parameters such as roll, pitch, yaw, and heading, providing real-time data on the ROV’s position along the X, Y, and Z axes to ensure precise orientation. These data are then utilized to generate and process 3D imaging and develop a corresponding 3D model of the operational ROV underwater, accurately reflecting its orientation in a visual representation by using an open-source platform. Due to constraints set by an agreement with the working class ROV operators, only short-term tests (up to 1 min) could be performed at the dockyard. A video demonstration of a working class ROV replica moving and reflecting in a 3D simulation in real-time was also presented. Despite these limitations, our findings demonstrate the feasibility and potential of a cost-effective 3D orientation visualization system for working class ROVs. With mean absolute error (MAE) error less than 2%, the results align with the performance expectations of the actual working ROV.

The purpose of this study is to develop and validate a simple unsafe behavior checklist to assess the extent of unsafe behavior among workers in an industrial setting. The checklist was developed using Focus Group Interview (FGI) and Analytical Hierarchy Process (AHP) analysis methodology. Preliminary testing was conducted with an unspecified sample and the correlation between unsafe behavior and accident experience was validated. The analyzed and compared the correlation between the type of unsafe behavior and accident experience and demonstrated the suitability of the unsafe behavior checklist. A risk sensitivity and risk-taking checklist was employed to identify five types of unsafe behavior. This study concludes that the unsafe behavior checklist can be used to predict accident concerns among workers with high types of dangerous behavior. This can help improve unsafe behavior and reduce the frequency of incidents. Therefore, the "Unsafe behavior Checklist" developed in this study can be used as an early indicator of the extent to which workers are aware of dangers in industrial workplaces in order to prevent accidents.

Abstract Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO2 reduction to solar fuels. A surface‐modified Ag@Ru‐P25 photocatalyst with H2O2 treatment was designed in this study to convert CO2 and H2O vapor into highly selective CH4. Ru doping followed by Ag nanoparticles (NPs) cocatalyst deposition on P25 (TiO2) enhances visible light absorption and charge separation, whereas H2O2 treatment modifies the surface of the photocatalyst with hydroxyl (–OH) groups and promotes CO2 adsorption. High‐resonance transmission electron microscopy, X‐ray photoelectron spectroscopy, X‐ray absorption near‐edge structure, and extended X‐ray absorption fine structure techniques were used to analyze the surface and chemical composition of the photocatalyst, while thermogravimetric analysis, CO2 adsorption isotherm, and temperature programmed desorption study were performed to examine the significance of H2O2 treatment in increasing CO2 reduction activity. The optimized Ag1.0@Ru1.0‐P25 photocatalyst performed excellent CO2 reduction activity into CO, CH4, and C2H6 with a ~95% selectivity of CH4, where the activity was ~135 times higher than that of pristine TiO2 (P25). For the first time, this work explored the effect of H2O2 treatment on the photocatalyst that dramatically increases CO2 reduction activity.

This research addresses the crucial task of improving accuracy in the semantic segmentation of aerial imagery, essential for applications such as urban planning and environmental monitoring. This study emphasizes the significance of maintaining the Intersection over Union (IOU) score as a metric and employs data augmentation with the Patchify library, using a patch size of 256, to effectively augment the dataset, which is subsequently split into training and testing sets. The core of this investigation lies in a novel architecture that combines a U-Net framework with self-attention mechanisms and separable convolutions. The introduction of self-attention mechanisms enhances the model’s understanding of image context, while separable convolutions expedite the training process, contributing to overall efficiency. The proposed model demonstrates a substantial accuracy improvement, surpassing the previous state-of-the-art Dense Plus U-Net, achieving an accuracy of 91% compared to the former’s 86%. Visual representations, including original patch images, original masked patches, and predicted patch masks, showcase the model’s proficiency in semantic segmentation, marking a significant advancement in aerial image analysis and underscoring the importance of innovative architectural elements for enhanced accuracy and efficiency in such tasks.

This paper provides a systematic review of advanced control strategies for the two mostly acclaimed standalone/off-grid distributed generation (DG) systems, i.e., wind energy conversion systems (WECSs) and solar photovoltaic energy systems (PVESs). The existing literature individually studies each DG system and does not provide an appropriate categorization of available advanced control strategies. Thus, it is quite difficult to systematically comprehend the control requirements of overall standalone/off-grid DG systems. Unlike the existing literature, this paper conducts a systematic study based on a useful distinctive organization of the advanced control strategies for the standalone permanent magnet synchronous generator (PMSG)-/doubly-fed induction generator (DFIG)-based WECSs and PVESs. The generalized control configurations for both standalone/off-grid DG systems are specifically exhibited by assigning a control system (CS) with its inherent inputs and outputs for every power conditioning unit (PCU) in the corresponding generation system. The advanced control techniques for all CSs are distinctively classified based on the presented generalized control configurations for both DG systems. Then, a comprehensive review is performed on every control technique with regard to its control functionality in the particular CS. Last, significant future research recommendations are provided for both standalone DG systems keeping in view the improved control strategies and PCUs.

The ongoing expansion of the Fourth Industrial Revolution has led to a diversification of drone applications. Among them, this paper focuses on the critical technology required for load management using drones. Generally, when using autonomous drones, global positioning system (GPS) receivers attached to the drones are used to determine the drone’s position. However, GPS integrated into commercially available drones have an error margin on the order of several meters. This paper, proposes a method that uses fixed-size quick response (QR) codes to maintain the error of drone 3D localization within a specific range and enable accurate mapping. In the drone’s 3D localization experiment, the errors were maintained within a specific range, with average errors ranging from approximately 0 to 3 cm, showing minimal differences. During the mapping experiment, the average error between the actual and estimated positions of the QR codes was consistently around 0 to 3 cm.

Abstract This paper presents a state‐of‐the‐art comprehensive review of the modern control techniques for the widely recommended two distributed generation systems (DGSs) using permanent magnet synchronous generator (PMSG)‐ and doubly‐fed induction generator (DFIG)‐based wind turbines (WTs) and photovoltaic (PV) arrays in grid‐connected applications. The already published review papers individually study each DGS and also lack a systematic discussion on the control techniques without any suitable classification. This makes it difficult to study the comparatively improved performance of each control technique and comprehensively understand the control requirements of overall DGSs. Unlike existing literature, this paper first distinctively presents the generalized control configurations for both DGSs in the form of control blocks (CBs). Second, the modern control techniques suggested for each DGS are uniquely classified based on the CBs. Third, each CB is studied in detail considering its required control operation for the particular DGS component and recently proposed control techniques for its implementation. Furthermore, a detailed data analysis and comparative graphical illustrations are provided to appropriately study the merits and demerits of every state‐of‐the‐art control technique. Finally, the useful future research directions are presented to realize improved hardware components and control techniques for the grid‐connected WTs and PV arrays DGSs.

Abstract Energy storage systems are pivotal for maximising the utilisation of renewable energy sources for smart grid and microgrid systems. Among the ongoing advancements in energy storage systems, the power conditioning systems for energy storage systems represent an area that can be significantly improved by using advanced power electronics converter designs and control techniques. Normally, the battery, flywheel, ultracapacitor and superconducting magnetic energy storage are the types of energy storage systems that typically require power conditioning systems for efficient bidirectional power flows. Compared to the previous review papers, this paper critically reviews the power conditioning system configurations and control techniques from the perspective of energy storage system applications in the power systems. First, the power conditioning systems are categorised into DC bus power conditioning systems and AC bus power conditioning systems based on the output voltage types at the connected point. Next, the topologies and control configurations of popular power electronics are comparatively analysed to highlight their advantages and power system applications. Moreover, the control configurations are discussed in terms of the popular applications of energy storage systems, that is, power backup smoothing, frequency regulation, voltage regulation and power quality applications. In addition, the latest developments in the energy storage system such as multi‐functional energy storage system stacking, artificial intelligence for power conditioning system of energy storage systems and security of control of energy storage systems are critically analysed. Finally, the review is concluded by discussing industrial applications and future research trends for the power conditioning systems of energy storage systems.

This paper presents the design, analysis, and control of a dual transformer-based bidirectional DC/DC resonant converter featuring balanced voltage stress across all the resonant capacitors. Compared to existing topologies, the proposed converter has a dual-rectifier structure on the secondary side, which allows operation over a wide load range with balanced voltage stress across all resonant components. The transformer stress is greatly reduced by employing two small transformers, thus greatly lowering thermal as well electrical stresses on the transformers’ windings. Furthermore, by operating the primary-side interleaved converter at a fixed 50% duty, input current ripples are significantly reduced. The proposed controller consists of a feedforward control part for effective system uncertainty compensation and a feedback control part for the convergence of system error dynamics. Notably, state-plane trajectory theory is employed to derive accurate feedforward compensation terms. Additionally, the effect of resonant elements’ parameter mismatch is analyzed in detail. The designed controller was implemented using the TI TMS320F28377D DSP on a 3.3 kW prototype hardware board. Detailed experimental investigations under tough, practical operating conditions corroborate an effective bidirectional power transfer operation with a balanced voltage stress distribution in each resonant element.

The increasing emissions created by the large-scaled number of automobiles around the world pose severe threats to modern life by causing global warming issues and deteriorating air quality. These serious issues stimulate the essential demand for cleaner, safer, and more efficient vehicles, such as battery electric vehicles (BEVs). Unlike other studies on the charging technologies of BEVs, this paper gives a comprehensive state-of-the-art review on the charging technologies available for BEVs: wired charging and wireless charging technologies. First, the wired charging technologies are systematically classified into AC charging (indirect charging) and DC charging (direct charging) methods based on how the BEVs batteries are fed from the grid. Next, the configurations and commonly used topologies of wireless charging technologies for BEVs are thoroughly discussed. The leading institutes/companies driving advancements in both technologies are also acknowledged. Finally, this paper extensively highlights the recent and future research trends along with the industrial applications.

This paper presents an improved continuous control set model predictive control (CCS-MPC) scheme using a fuzzy logic approach (FLA) for three-phase constant voltage constant frequency (CVCF) inverters with an output LC filter. The proposed method can enhance the output voltage quality by using an optimal predictive control law (OPCL). Additionally, the proposed method corrects the input voltage commands through the FLA-based online gain tuning aiming to satisfy the hardware constraint. Thus, the proposed FLA-based CCS-MPC can guarantee an acceptable output voltage with a faster transient response, smaller steady-state error (SSE), and lower total harmonic distortion (THD). Moreover, a Kalman filter-based load current observer is used to significantly improve the reliability and robustness. Comparative experimental studies with another CCS-MPC method are conducted on a prototype three-phase CVCF inverter using TI TMS320F28335 DSP to validate the improved performance under the step-changes of linear/unbalanced/nonlinear loads with uncertain parameters.

This paper proposes a simple $1^{\mathrm {st}}$ -order disturbance observer (DO)-based optimal control (DOBOC) strategy for surface-mounted permanent magnet synchronous motor (SPMSM) drives. A detailed comparative analysis of three reduced-order (i.e., $1^{\mathrm {st}}$ , $2^{\mathrm {nd}}$ , and $3^{\mathrm {rd}}$ ) DOs has been presented in terms of structural complexity along with transient and steady-state performances. A simple $1^{\mathrm {st}}$ -order DOBOC is proposed with a considerably simple and easy gain tuning procedure without any complex equation and time-consuming weighting matrices selection while ensuring a competitive control performance. Also, the stability of three DOBOCs is proven using the Lyapunov function, which has not been carried out in the previous studies. Furthermore, this paper provides a detailed procedure to systematically select the controller and observer gains of three reduced-order (i.e., $1^{\mathrm {st}}$ , $2^{\mathrm {nd}}$ , and $3^{\mathrm {rd}}$ ) DOBOC by experiment. Comparative experiments are performed to confirm the feasibility of the proposed $1^{\mathrm {st}}$ -order DOBOC using a prototype SPMSM test-bed with a TI TMS320F28335 DSP. Finally, verification results and comparative table are presented to compare the speed tracking performance (e.g., transient response, undershoot (US), steady-state error (SSE), and robustness to load torque disturbances) of three reduced-order DOBOC methods under speed and load torque step-changes.

This paper proposes a theoretical and experimental implementation of an advanced sliding mode control (SMC) for a three-phase voltage source inverter (VSI) to achieve robustness against the unknown uncertainties of an LC filter. The significant contributions of the proposed SMC are summarized as considerations for the matched and mismatched uncertainties of the LC filter, more relaxed norm-bounds, dynamic characterization of sliding surface, and unique stability analysis. Unlike the conventional SMC techniques with matched uncertainties, the mismatched uncertainties in the state matrix are taken for the design of the proposed SMC. Also, the relaxed norm-bound designed for matched and mismatched uncertainties allows a wide range of variations in the values of LC filter. The voltage tracking errors are significantly reduced and the total harmonic distortions (THDs) are highly suppressed by characterizing the sliding surface in terms of flexible linear matrix inequalities (LMIs). Next, the stability analysis and reachability conditions are given using the Lyapunov criterion. The authenticity of the proposed SMC method is proved by TMS320LF28335 DSP based experimental results with a prototype 1-kVA test-bed. The comparative experimental results and analysis for the proposed SMC scheme, the conventional SMC scheme, and the conventional PI-PI control scheme are presented under the load step change, unbalanced load, and non-linear load step change with the parameter uncertainties to demonstrate the excellent performance of the proposed controller such as fast transient response, small steady-state error, and low THD.

This paper proposes an improved torque ripple minimization (TRM) method using model-based loss minimization (LM) control to reduce the torque ripples and enhance the efficiency for surface-mounted permanent magnet synchronous motor (SPMSM) drives. The conventional SPMSM drives usually achieve the maximum torque per ampere (MTPA) control by applying the zero d-axis current (ZDC) and ignore an actual core loss resistance in the controller design. Unlike the conventional MTPA method, the proposed TRM selects the appropriate d-axis current value by making the derivative of the electromagnetic torque equal to zero in the SPMSM drives. Consequently, the proposed method can improve the torque ripples and efficiency compared to the conventional MTPA. Using the proportional-integral (PI) controllers, comparative experimental verifications between the proposed model-based TRM, the conventional model-based MTPA, and the conventional model-based LM are performed through a prototype SPMSM drive with a TI TMS320F28335 digital signal processor (DSP).

This paper proposes a nonlinear disturbance observer (NDO)-based sliding mode speed controller (SMSC) to guarantee the superior control performance in terms of robustness, fast transient response, and small steady-state error for a surface-mounted permanent magnet synchronous motor (SPMSM) drive. Generally, the control performance of the SPMSM drives can be degraded by disturbances, so an NDO with a proper disturbance rejection capability is proposed to appropriately improve the tracking performance of the SMSC designed for the SPMSM drives. Unlike the linear disturbance observers (LDOs), the proposed NDO can efficiently estimate the lumped disturbance such as uncertainties parameters and unmodeled dynamics by using the nonlinear design function. The proposed NDO rejects the complex disturbances as well as self-regulates the observer gains to increase the convergence rate. The feasibility of the proposed NDO-based SMSC is verified by using a MATLAB/Simulink software program and a prototype SPMSM drive system with a TI TMS320F28335 digital signal processor (DSP). The comparative results with a conventional LDO-based SMSC are analyzed under load torque disturbances and model uncertainties to prove the excellent performance of the proposed NDO-based SMSC.

We evaluated contemporary trends in radical prostatectomy (RP) in men aged >70 years and investigated associations of selected variables with recovery of urinary continence (UC) in two age groups: >70 and ≤ 70 years. A retrospective cohort of 2301 eligible patients attending our institution from 2004 to 2015 was reviewed. Patients were divided into two groups based on age at surgery (>70 years [n = 610] vs 70 years [n = 1691]) and four groups by year of surgery. Over the study period, the proportion of patients aged >70 years gradually increased up to 30.0%, and the rate of robot-assisted RP and neurovascular bundle (NVB) saving increased continually to 80.0% and 67.4% of older patients, respectively. Although the rate of recovery of UC within 12 months (3 months) in patients aged >70 years was lower than that in those aged ≤ 70 years (81.5% [52.6%] vs 88.6% [60.9%], respectively; both P < 0.001), the gap between age groups in the rate of recovery within 12 months narrowed from the second quarter of the study period. Among younger patients, age, robot-assisted RP, prostate volume, membranous urethral length (MUL), and NVB saving were predictors of recovery of UC within 3 or 12 months. In contrast, only age and MUL were predictors of recovery of UC within 3 and 12 months in patients aged >70 years. Therefore, unlike younger patients, only variables (age and MUL), possibly associated with the inherent function of the urinary sphincter, were predictors of recovery of UC in patients aged >70 years.

This paper designs an adaptive sliding mode speed controller (ASMSC) that can compensate for parameter uncertainty of an interior permanent magnet synchronous motor (IPMSM) drive. Unlike the previous control systems, the proposed ASMSC guarantees a precise speed tracking capability in the presence of severe parameter variations without accurate knowledge on the motor parameter values and uncertainty bounds. In particular, the proposed adaptive switching gain tuning (ASGT) term can effectively solve the excessive input energy consumption problem due to an unnecessarily overestimated switching gain. Next, the convergence and stability analysis are proven through a Lyapunov function. The feasibility of the proposed approach is verified via experimental results using a prototype IPMSM test bed with a TI TMS320F28335 digital signal processor. In this paper, the proposed SMSC is investigated with two control terms: without an ASGT term and with an ASGT term. In addition, the conventional proportional-integral speed controller and conventional linear matrix inequalities based sliding mode speed controller are chosen for the performance comparison. Finally, the proposed ASMSC can assure more robust and faster speed performances against the parameter uncertainty under three dynamic load conditions.

This paper proposes a simplified near optimal control (NOC) scheme to reject the disturbances of interior permanent magnet synchronous motor (IPMSM) drives by minimizing the complex calculations in the Taylor series method required for solving the state-dependent Riccati equation (SDRE). Since the speed tracking performance of an IPMSM can be significantly degraded in the presence of the disturbances owing to the practical factors (e.g., external load torque, parameter uncertainties, and so on), an SDRE-based near optimal disturbance observer (NODO) is designed to accurately estimate and reject the disturbances associated with the speed and current in the feedforward control. The state-dependent coefficient matrices of the IPMSM are rearranged in the controller and observer to minimize the complex offline calculations of the Taylor series method used to solve the SDRE. By significantly simplifying the calculations, the proposed SDRE-based NOC scheme can be efficiently applied to the IPMSM drives. To verify the precise and robust control performance of the proposed NODO-based near optimal speed controller, experiments are conducted via a prototype IPMSM drive system with a TI-TMS320F28335 DSP under different disturbances. Finally, the comparative experimental results with the conventional NOC are presented under load change and wide speed range conditions.

This paper proposes an improved model predictive control (MPC) scheme with a robust prediction and stability-constrained finite states for three-phase voltage source inverters (3Φ-VSIs) with an LC filter. In this paper, the stability-constrained finite states are selected via the asymptotic stability conditions as a key factor to reduce the total harmonic distortions (THDs) and steady-state errors. Meanwhile, the Kalman filter-based observers improve the overall robustness against model mismatches and noises via a robust prediction. To select the stabilized finite states, the stability conditions are derived by the equivalent feedback-gains and constrained in the exhausting search of the proposed finite-set (FS) MPC. Unlike conventional FS-MPC methods, three control targets (i.e., robustness, stability, and optimality) are simultaneously achieved as the new contributions to remarkably enhance the voltage control performance of the 3Φ-VSI, which are also the challenge of the conventional control methods. To verify the superiority of the proposed FS-MPC, comparative studies are conducted on a prototype three-wire 3Φ-VSI system with a TI TMS320F28335 DSP under practical conditions (i.e., parameter mismatches, linear/nonlinear-load step-changes). The experimental results confirm that the performance of the proposed FS-MPC has been significantly improved in terms of lower THDs, smaller steady-state errors, faster dynamic response, and more robustness under critical system changes as compared with the conventional FS-MPC.

This paper proposes a robust high-order disturbance observer (HODO) for the state-dependent Riccati equation (SDRE)-based suboptimal speed controller of an interior permanent magnet synchronous motor (IPMSM) drive. The conventional disturbance observers (DOs) cannot accurately estimate the fast time-varying disturbances of an IPMSM during the transient-state because the disturbances are assumed to change slowly, so the inaccurately estimated disturbances lead to conservative robust control. Unlike the conventional DOs, the proposed HODO guarantees the fast convergence of the estimated error for an IPMSM drive by accurately estimating the fast time-varying disturbances and their all high-order derivatives. Also, it is specifically applicable to the SDRE based suboptimal speed controller which cannot completely eliminate the steady-state error in the presence of mismatched disturbances and uncertainties. Finally, the simulation results via a MATLAB/Simulink package and the experimental results via a prototype IPMSM test-bed having TI TMS320F28335 DSP are presented to verify the faster dynamic response, smaller steady-state error, and more robust response of the SDRE speed controller with the proposed HODO compared with the conventional 1st-order DO, conventional generalized proportional integral observer (GPIO), and conventional SDRE observer.

We evaluated whether the prostate-specific antigen (PSA) mass or free PSA (fPSA) mass (i.e., absolute amount of total circulating PSA or fPSA protein, respectively), versus serum PSA or fPSA concentration, improves the accuracy of predicting the total prostate volume (TPV) in relation to obesity. Among men whose multicore (≥12) transrectal prostate biopsy was negative, 586 who had a PSA of ≤10 ng ml−1 and underwent the fPSA test prior to biopsy were enrolled. The PSA mass or fPSA mass (μ g) was calculated by multiplying the serum level by plasma volume. At each TPV cut-off point (30 ml, 40 ml, and 50 ml), the areas under the receiver operating characteristics curve (AUCs) of each variable were compared in obesity-based subgroups. AUCs of fPSA and fPSA mass for predicting TPV were significantly larger than those for PSA and PSA mass by 8.7%–12.1% at all cut-off points. Subgroup analyses based on obesity showed that, although PSA mass and fPSA mass enhanced accuracy by 4% (P = 0.031) and 1.8% (P = 0.003), respectively, for determining TPVs of ≥30 ml and ≥50 ml in obese and overweight men, they did not improve the accuracy in most other combinations of the degrees of obesity with TPV cut-off points. Thus, compared with serum PSA or fPSA, the absolute amount of PSA or fPSA protein mass improved the accuracy of predicting TPV in obese men very minimally and only for certain TPV cut-off points. Hence, these indicators may not provide clinically meaningful improvement in predicting TPV in obese men.

As the elderly population increases globally, the demand for systems and algorithms that target the elderly is increasing. Focusing on the extendibility of smart mirrors, our purpose is to create a motion detection system based on video input by an attached device (an RGB camera). The motion detection system presented in this paper is based on an algorithm that returns a Boolean value indicating the detection of motion based on skeletal information. We analyzed the problems that occur when the adjacent frame subtraction method (AFSM) is used in the motion detection algorithm based on the skeleton-related output of the pose estimation model. We compared and tested the motion recognition rate for slow-motion with the previously used AFSM and the vector sum method (VSM) proposed in this paper. As an experimental result, the slow-motion detection rate showed an increase of 30–70%.

The mitogenome of Myuroclada maximowiczii (GenBank accession number MT834960) has a total length of 104,216 bp and encodes 40 protein-coding genes, three ribosomal RNAs, and 24 transfer RNAs. The overall nucleotide composition is asymmetric (29.6% A, 29.4% T, 21.2% G, and 19.8% C), with AT content (59.0%) higher than GC content (41.0%). The gene arrangement of this mitogenome is identical to that in other bryophytes. Phylogenetic trees were constructed using complete mitochondrial genome sequences of 24 bryophytes publicly available in GenBank and the mitogenome sequence derived in this study. Our phylogenetic analysis revealed that M. maximowiczii clustered in a clade with other hypnalean taxas.

Computed tomography (CT) perfusion can analyze tissue perfusion and quantitative parameters, including blood flow, blood volume, and transit time. CT perfusion has been used for evaluating split renal function. However, its applicability in veterinary medicine was not validated. This study aimed to evaluate the correlation of renal blood flow (RBF) derived by maximum slope-based CT perfusion and an ultrasonic flow probe and assess the effect of the presence of a pre-existing contrast medium on CT perfusion in the kidneys. In five healthy purpose-bred beagles, CT perfusion was performed at the level of the left renal hila after injection of 1 mg/kg iohexol, during measuring RBF with an ultrasonic flow probe placed on the left renal artery. After post-contrast CT scan with injection of 2 mg/kg iohexol, CT perfusion scan was repeated with the same protocol used in the first perfusion study. The CT perfusion derived RBF was analyzed based on the maximum slope and was compared with the true RBF obtained using an ultrasonic flow probe. Results indicated that CT perfusion derived RBF was significantly correlated with true RBF, although CT perfusion derived RBF did not match the absolute value of the true RBF. It was correlated with the true RBF, even in the presence of a pre-existing contrast medium in the kidney. CT perfusion can estimate the change in individual renal perfusion non-invasively, and this method can be used supplementary to the conventional CT protocol in clinic.

Shear wave elastography (SWE) induces lateral shear wave through acoustic pulses of the transducer and evaluates tissue stiffness quantitatively. This study was performed to evaluate feasibility and reproducibility of two-dimensional shear wave elastography (2D SWE) for evaluation of tissue stiffness and to examine technical factors that affect shear wave speed (SWS) measurements in adult dogs. Nine healthy, 2 year-old, adult beagles with the median weight of 9.8 kg were included. In this prospective, experimental, exploratory study, 2D SWE (Aplio 600) from the liver, spleen, kidneys, pancreas, prostate, lymph nodes (submandibular, retropharyngeal, axillary, medial iliac, and inguinal), submandibular salivary gland, and thyroid was performed in anesthetized beagles. Color map was drawn and SWS of each SWE were measured as Young’s modulus (kPa) and shear wave velocity (m/s). The effect of measuring site, scan approach, depth, and anesthesia on SWE was assessed in abdominal organs by two observers independently. A total of 27 SWE examinations were performed in 12 organs by each observer. All SWS measurements were preformed successfully; however, SWE in the renal medulla could not be successfully conducted, and it was excluded from further analysis. Interobserver agreement of SWE was moderate to excellent in all organs, except for the left liver lobe at 10–15 mm depth with the intercostal scan. In the liver, there was no significant effect of the measuring site and scan approach on SWE. SWS of the liver and spleen tended to be higher with increasing the depth, but no significant difference. However, anesthesia significantly increased tissue stiffness in the spleen compared to awake dog regardless of the depth (P < 0.05). There was a significant difference in SWS according to the measuring site in the kidneys and pancreas (P < 0.001). 2D SWE was feasible and highly reproducible for the estimation of tissue stiffness in dogs. Measuring site and anesthesia are sources of variability affecting SWE in abdominal organs. Therefore, these factors should be considered during SWS measurement in 2D SWE. This study provides basic data for further studies on 2D SWE on pathological conditions that may increase tissue stiffness in dogs.

This paper proposes a post-processing method called bidirectional interpolation method for sampling-based path planning algorithms, such as rapidly-exploring random tree (RRT). The proposed algorithm applies interpolation to the path generated by the sampling-based path planning algorithm. In this study, the proposed algorithm is applied to the path created by RRT-connect and six environmental maps were used for the verification. It was visually and quantitatively confirmed that, in all maps, not only path lengths but also the piecewise linear shape were decreased compared to the path generated by RRT-connect. To check the proposed algorithm’s performance, visibility graph, RRT-connect algorithm, Triangular-RRT-connect algorithm and post triangular processing of midpoint interpolation (PTPMI) were compared in various environmental maps through simulation. Based on these experimental results, the proposed algorithm shows similar planning time but shorter path length than previous RRT-like algorithms as well as RRT-like algorithms with PTPMI having a similar number of samples.

The present study reports the complete mitochondrial genome of Myurella julacea (Schwägr.) Schimp. (GenBank accession number MT850126); the genome size was 104,979 bp. The gene arrangement was found to be similar to that in other bryophytes, and the genome consisted of 40 protein-coding genes (PCGs), 3 ribosomal RNAs (rRNAs), and 24 transfer RNAs (tRNAs). The phylogenic relationship was analyzed by construction of a phylogenetic tree based on the mitogenome of M. julacea and 25 other bryophytes publicly available in GenBank. The complete mitogenome of M. julacea is expected to provide insights into the evolution of species belonging to the order Hypnales.

To identify the dietary composition and characteristics of both Adélie (Pygoscelis adeliae) and Emperor (Aptenodytes forsteri) penguins at four breeding sites, we performed stable carbon (δ13C) and nitrogen (δ15N) isotope analysis of down samples taken from penguin chicks. Adélie Penguin chicks at Cape Hallett mostly fed on Antarctic krill (Euphausia superba; 65.5 ± 3.5%), a reflection of the prevalence of that species near Cape Hallett, and no significant differences were noted between 2017 and 2018. However, Adélie Penguin chicks at Inexpressible Island, located near Terra Nova Bay, fed on both Antarctic silverfish (Pleuragramma antarctica; 42.5%) and ice krill (Euphausia crystallorophias; 47%), reflecting the high biomass observed in Terra Nova Bay. Meanwhile, no significant difference was noted between the two breeding sites of the Emperor Penguin. Emperor Penguin chicks predominantly fed on Antarctic silverfish (74.5 ± 2.1%) at both breeding sites (Cape Washington and Coulman Island), suggesting that diet preference represents the main factor influencing Emperor Penguin foraging. In contrast, the diet of the Adélie Penguin reflects presumed regional differences in prey prevalence, as inferred from available survey data.

It is difficult to guarantee optimality using the sampling-based rapidly-exploring random tree (RRT) method. To solve the problem, this paper proposes the post triangular processing of the midpoint interpolation method to minimize the planning time and shorten the path length of the sampling-based algorithm. The proposed method makes a path that is closer to the optimal path and somewhat solves the sharp path problem through the interpolation process. Experiments were conducted to verify the performance of the proposed method. Applying the method proposed in this paper to the RRT algorithm increases the efficiency of optimization by minimizing the planning time.

In many seabirds, individuals abstain from eating during the moult period. Penguins have an intense moult that lasts for weeks, during which they are confined to land. Despite the importance for survival, it is still unclear how the faecal microbiota of Antarctic penguins changes in response to the moult fast. Here, we investigated the faecal microbiota of chinstrap (Pygoscelis antarcticus) and gentoo penguins (Pygoscelis papua) on King George Island, Antarctica. The bacterial community compositions during the feeding and moulting stages were compared for both species using bacterial 16S rRNA gene amplicon on an Illumina MiSeq platform. Our results showed that the moult fast altered the bacterial community structures in both penguin species. Interestingly, the bacterial community composition shifted in the same direction in response to the moult fast but formed two distinct clusters that were specific to each penguin species. A significant increase in bacterial diversity was observed in gentoo penguins, whereas no such change was observed for chinstrap penguins. By analysing the contribution of the ecological processes that determine bacterial community assembly, we observed that processes regulating community turnover were considerably different between the feeding and moulting stages for each penguin. At the phylum level, the relative abundances of Fusobacteria, Firmicutes and Proteobacteria were dominant in chinstrap penguins, and no significant changes were detected in these phyla between the feeding and moulting periods. Our results suggest that moult fast-induced changes in the faecal microbiota occur in both species.

This paper proposed a triangular inequality-based rewiring method for the rapidly exploring random tree (RRT)-Connect robot path-planning algorithm that guarantees the planning time compared to the RRT algorithm, to bring it closer to the optimum. To check the proposed algorithm’s performance, this paper compared the RRT and RRT-Connect algorithms in various environments through simulation. From these experimental results, the proposed algorithm shows both quicker planning time and shorter path length than the RRT algorithm and shorter path length than the RRT-Connect algorithm with a similar number of samples and planning time.

Environment maps must first be generated to drive mobile robots automatically. Path planning is performed based on the information given in an environment map. Various types of sensors, such as ultrasonic and laser sensors, are used by mobile robots to acquire data on its surrounding environment. Among these, the laser sensor, which has the property of being able to go straight and high accuracy, is used most often. However, the beams from laser sensors are refracted and reflected when it meets a transparent obstacle, thus generating noise. Therefore, in this paper, a state-of-the-art algorithm was proposed to detect transparent obstacles by analyzing the pattern of the reflected noise generated when a laser meets a transparent obstacle. The experiment was carried out using the environment map generated by the aforementioned method and gave results demonstrating that the robot could avoid transparent obstacles while it was moving towards the destination.

The Cape petrel Daption capense, a seabird, is observed throughout the southern hemisphere including the Antarctic region. Herein, we report the complete mitogenome of Cape petrel with the GenBank accession number MH924023 to elucidate the genetic characteristics of this genus. The mitogenome is 17,312 bp long and comprises 13 protein-coding genes (PCGs), two rRNA genes, and 22 tRNA genes. The overall base composition of the 13 PCGs is as follows: A (31.1%), C (30.3%), T (25.4%), and G (13.2%), with a GC content of 43.5%. The results provide useful information for further genetic studies in Procellariiformes.

To evaluate whether the risk of prostate cancer was different according to the pattern of fluctuation in prostate-specific antigen (PSA) levels in patients undergoing repeat transrectal ultrasound-guided prostate biopsy (TRUS-Bx). Methods: From March 2003 to December 2012, 492 patients underwent repeat TRUS-Bx. The patients were stratified into 3 groups based on the PSA fluctuation pattern: group 1 (continuous elevation of PSA, n=169), group 2 (PSA fluctuation with PSA velocity [PSAV]=1.0 ng/mL/yr, n=123), and group 3 (PSA fluctuation with PSAV

A major limitation of performing hemiablative focal therapy (FT) for prostate cancer (PCa) is the possibility of accompanying significant cancer in the contralateral side of the prostate that is missed on prostate biopsy. We attempted to verify whether clinical and biopsy-related parameters can be used to predict the absence of significant cancer in the prostate lobe. Methods: We assumed that hemiablative FT could be performed in patients with low-risk PCa, with unilateral tumors as assessed by transrectal ultrasound-guided biopsy. We evaluated 214 patients who had undergone radical prostatectomy (RP) and fulfilled the eligibility criteria. Seemingly preserved lobes, defined by the absence of cancer on biopsy, were classified as lobes with no cancer (LNC), lobes with insignificant cancer (LIC), and lobes with significant cancer (LSC) according to RP pathology. Cases with an estimated tumor volume of

There are various motion planning techniques for robots or agents, such as bug algorithm, visibility graph, Voronoi diagram, cell decomposition, potential field, and other probabilistic algorithms. Each technique has its own advantages and drawbacks, depending on the number and shape of obstacles and performance criteria. Especially, a potential field has vector values for movement guidance to the goal, and the method can be used to make an instantaneous and smooth robot movement path without an additional controller. However, there may be some positions with zero force value, called local minima, where the robot or agent stops and cannot move any further. There are some solutions for local minima, such as random walk or backtracking, but these are not yet good enough to solve the local minima problem. In this paper, we propose a novel movement guidance method that is based on the water sink model to overcome the previous local minima problem of potential field methods. The concept of the water sink model is to mimic the water flow, where there is a sink or bathtub with a plughole and floating piece on the water. The plughole represents the goal position and the floating piece represents robot. In this model, when the plug is removed, water starts to drain out via the plughole and the robot can always reach the goal by the water flow. The water sink model simulator is implemented and a comparison of experimental results is done between the water sink model and potential field.

The Expanded Douglas⁻Peucker (EDP) polygonal approximation algorithm and its application method for the Opposite Angle-Based Exact Cell Decomposition (OAECD) are proposed for the mobile robot path-planning problem with curvilinear obstacles. The performance of the proposed algorithm is compared with the existing Douglas⁻Peucker (DP) polygonal approximation and vertical cell decomposition algorithm. The experimental results show that the path generated by the OAECD algorithm with EDP approximation appears much more natural and efficient than the path generated by the vertical cell decomposition algorithm with DP approximation.

One emerging biometric identification method is the use of human footprint. However, in the previous research, there were some limitations resulting from the spatial resolution of sensors. One possible method to overcome this limitation is through the use additional information such as dynamic walking information in sequential walking footprint. In this study, we suggest a new person recognition scheme based on both overlapped foot shape and COP (Center Of Pressure) trajectory during one-step walking. And, we show the usefulness of the suggested method, obtaining a 98.6% recognition rate in our experiment with eleven people. In addition, we show an application of the suggested method, automatic door-opening system for intelligent residential space.

This paper proposes an adaptive duty-cycled hybrid X-MAC (ADX-MAC) protocol for energy-efficient forest fire prediction. The Asynchronous sensor network protocol, X-MAC protocol, acquires additional environmental status details from each forest fire monitoring sensor for a given period, and then changes the duty-cycle sleep interval to efficiently calculate forest fire occurrence risk according to the environment. Performance was verified experimentally, and the proposed ADX-MAC protocol improved throughput by 19% and was 24% more energy efficient compared to the X-MAC protocol. The duty-cycle was shortened as forest fire probability increased, ensuring forest fires were detected at faster cycle rate.

A dual-band circularly polarized (CP) dielectric resonator antenna (DRA) designed on multi-layer substrates is proposed. An asymmetric C-shaped metallic strip is also incorporated into the upper side of the top substrate in the proposed design. The hexagonal dielectric resonator (DR) is excited by the proposed 3-D meandered probe, which generates multiple orthogonal TE-modes. It is found that the lower CP band arises due to the pair of fundamental modes of the hexagonal DR. In the upper CP band, pairs of higher broadside and even modes of the hexagonal DR are combined with a CP band that is induced by the asymmetric C-shaped metallic strip to yield a wide 3 dB axial ratio bandwidth (ARBW). A prototype of the proposed DRA is fabricated for experimental verification. The antenna exhibits a measured −10 dB reflection bandwidth of 56.43% (2.15–3.84 GHz). The far-field measurement shows measured 3 dB ARBWs of 7.56% (2.29–2.47 GHz) with a peak gain of 5.6 dBic and 16.47% (3.12–3.68 GHz) with a peak gain of 7.84 dBic in the lower and upper bands, respectively.

A new human-friendly assistive home environment, Intelligent Sweet Home (ISH), developed at KAIST, Korea for testing advanced concepts for independent living of the elderly/the physically handicapped. The concept of ISH is to consider the home itself as an intelligent robot. ISH always checks the intention or health status of the resident. Therefore, ISH can do actively the most proper services considering the resident's life-style by the detected intention or emergency information. But, when there are more than two residents, ISH cannot consider the residents' characteristics or tastes if ISH cannot identify who he/she is before. To realize a personalized service system in the intelligent residential space like ISH, we deal with a human-friendly user identification method for ubiquitous computing environment, specially focused on dynamic human footprint recognition. And then, we address some case studies of personalized services that have been experienced by Human-friendly Welfare Robot System research center, KAIST.

A vertical-strip-fed dielectric resonator antenna exhibiting broadband circular polarization characteristics is presented. A broad 3 dB axial ratio bandwidth (ARBW) is achieved by combining multiple orthogonal modes due to the use of a special-shaped dielectric resonator. The proposed antenna is fabricated to evaluate its actual performance capabilities. The antenna exhibits a measured 3 dB ARBW of 44.2% (3.35–5.25 GHz), lying within a −10 dB reflection bandwidth of 82.7% (2.44–5.88 GHz). The measured peak gain within 3 dB ARBW is found to be 5.66 dBic at 4.8 GHz. The measured results are in good agreement with the simulated results.

OBJECTIVES: We developed a mobile application-based Seoul National University Prostate Cancer Risk Calculator (SNUPC-RC) that predicts the probability of prostate cancer (PC) at the initial prostate biopsy in a Korean cohort. Additionally, the application was validated and subjected to head-to-head comparisons with internet-based Western risk calculators in a validation cohort. Here, we describe its development and validation. PATIENTS AND METHODS: As a retrospective study, consecutive men who underwent initial prostate biopsy with more than 12 cores at a tertiary center were included. In the development stage, 3,482 cases from May 2003 through November 2010 were analyzed. Clinical variables were evaluated, and the final prediction model was developed using the logistic regression model. In the validation stage, 1,112 cases from December 2010 through June 2012 were used. SNUPC-RC was compared with the European Randomized Study of Screening for PC Risk Calculator (ERSPC-RC) and the Prostate Cancer Prevention Trial Risk Calculator (PCPT-RC). The predictive accuracy was assessed using the area under the receiver operating characteristic curve (AUC). The clinical value was evaluated using decision curve analysis. RESULTS: PC was diagnosed in 1,240 (35.6%) and 417 (37.5%) men in the development and validation cohorts, respectively. Age, prostate-specific antigen level, prostate size, and abnormality on digital rectal examination or transrectal ultrasonography were significant factors of PC and were included in the final model. The predictive accuracy in the development cohort was 0.786. In the validation cohort, AUC was significantly higher for the SNUPC-RC (0.811) than for ERSPC-RC (0.768, p

Currently, no standardized method is available to predict success rate after percutaneous nephrolithotomy. We devised and validated the Seoul National University Renal Stone Complexity (S-ReSC) scoring system for predicting the stone-free rate after single-tract percutaneous nephrolithotomy (sPCNL).The data of 155 consecutive patients who underwent sPCNL were retrospectively analyzed. Preoperative computed tomography images were reviewed. The S-ReSC score was assigned from 1 to 9 based on the number of sites involved in the renal pelvis (#1), superior and inferior major calyceal groups (#2-3), and anterior and posterior minor calyceal groups of the superior (#4-5), middle (#6-7), and inferior calyx (#8-9). The inter- and intra-observer agreements were accessed using the weighted kappa (κ). The stone-free rate and complication rate were evaluated according to the S-ReSC score. The predictive accuracy of the S-ReSC score was assessed using the area under the receiver operating characteristic curve (AUC).The overall SFR was 72.3%. The mean S-ReSC score was 3.15±2.1. The weighted kappas for the inter- and intra-observer agreements were 0.832 and 0.982, respectively. The SFRs in low (1 and 2), medium (3 and 4), and high (5 or higher) S-ReSC scores were 96.0%, 69.0%, and 28.9%, respectively (p