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Biofilms are communities of bacteria, fungi or yeasts that form on diverse biotic or abiotic surfaces, and play important roles in pathogenesis and drug resistance. A generic saw palmetto oil inhibited biofilm formation by Staphylococcus aureus, Escherichia coli O157:H7 and fungal Candida albicans without affecting their planktonic cell growth. Two main components of the oil, lauric acid and myristic acid, are responsible for this antibiofilm activity. Their antibiofilm activities were observed in dual-species biofilms as well as three-species biofilms of S. aureus, E. coli O157:H7 and C. albicans. Transcriptomic analysis showed that lauric acid and myristic acid repressed the expressions of haemolysin genes (hla and hld) in S. aureus, several biofilm-related genes (csgAB, fimH and flhD) in E. coli and hypha cell wall gene HWP1 in C. albicans, which supported biofilm inhibition. Also, saw palmetto oil, lauric acid and myristic acid reduced virulence of three microbes in a nematode infection model and exhibited minimal cytotoxicity. Furthermore, combinatorial treatment of fatty acids and antibiotics showed synergistic antibacterial efficacy against S. aureus and E. coli O157:H7. These results demonstrate that saw palmetto oil and its main fatty acids might be useful for controlling bacterial infections as well as multispecies biofilms.

Uptake of the commonly occurring cyanobacterial toxin microcystin-LR (MC-LR) into crop plants via spray irrigation has been demonstrated. As other hazardous compounds such as pesticides were shown to be transported within plants, it was essential to understand the transport and fate of MC-LR in plants and the risks posed to grazers and other consumers. Of specific interest was to investigate if MC-LR could be detected in guttation drops and the toxicity thereof. Triticum aestivum (wheat) seedlings were exposed to 100 μg L−1 MC-LR in two separate experiments during which guttation drops were collected at various time points. The plants of one experiment were sectioned to investigate MC-LR distribution to the various plant appendages via liquid chromatography-tandem mass spectrometry analysis. After exposure, MC-LR could be detected in the roots, stems, leaves, and the guttation drops. However, the guttation drops were not toxic to Daphnia. As the environmentally relevant toxin concentration used was not sufficient to promote mortality in Daphnia, the physiological effect in insects, which rely on guttation drops as a water source, remains unknown. Combined with other contaminants that insects may be exposed to, the additional MC-LR exposure could contribute to the overall toxicity through the “tears of death”.

This paper proposes a global backlight dimming algorithm based on structural similarity that controls the local distortion level of the output image for preserving overall image quality. Unlike existing methods, the proposed method non-iteratively determines a global clipping point that maintains structural similarity for each pixel above the desired level. The proposed method consists of three steps: region analysis, candidate clipping point calculation, and backlight luminance determination. In the first step, the structural similarity is analyzed based on various clipping points. In the second step, the proposed method estimates a candidate clipping point, which preserves the structural similarity index of each pixel above the desired level, based on the estimation of local statistics. Then, the proposed method determines a global clipping point based on a group of candidate clipping points. Finally, the output luminance is determined based on the selected global clipping point. Experimental results showed that the proposed method successfully maintained the structural similarity of each pixel above the desired level. In addition, the proposed method reduced the variation of minimum structural similarity by up to 94.7% compared to the benchmark methods.

We found that the activated carbon-molecular oxygen system promotes the conversion of hydroquinones to benzoquinones, naphthoquinones, and anthraquinones, which are often found in natural products and pharmaceuticals. In particular, the one-pot synthesis of naphthoquinones and anthraquinones involving a Diels-Alder reaction is a useful protocol for this purpose.

In this study, a seismic isolator placed on the base of a structure was optimized under various earthquake records using an adaptive harmony search algorithm (AHS). As known, the base-isolation systems with very low stiffness provide a rigid response of superstructure, so it was assumed that the structure is rigid and the base-isolated structure can be considered as a single-degree of freedom structure. By using this assumption, an optimization method that is independent of structural properties but specific to the chosen earthquake excitation set is proposed. By taking three different damping ratio limits and isolator displacement limits, the isolator period and damping ratio were optimized so that the acceleration of the structure was minimized for nine cases. In the critical seismic analysis performed with optimum isolator parameters, the results obtained for different damping ratios and isolator periods were compared. From the results, it is determined that isolators with low damping ratios require more ductility, and as the damping ratio increases, further restriction of the movement of the isolator increases the control efficiency. Thus, it is revealed that increasing the ductility of the isolator is effective in reducing the total acceleration in the structure.

This paper explores new techniques that are based on a hidden‐layer linear transformation for fast speaker adaptation used in deep neural networks (DNNs). Conventional methods using affine transformations are ineffective because they require a relatively large number of parameters to perform. Meanwhile, methods that employ singular‐value decomposition (SVD) are utilized because they are effective at reducing adaptive parameters. However, a matrix decomposition is computationally expensive when using online services. We propose the use of an extended diagonal linear transformation method to minimize adaptation parameters without SVD to increase the performance level for tasks that require smaller degrees of adaptation. In Korean large vocabulary continuous speech recognition (LVCSR) tasks, the proposed method shows significant improvements with error‐reduction rates of 8.4% and 17.1% in five and 50 conversational sentence adaptations, respectively. Compared with the adaptation methods using SVD, there is an increased recognition performance with fewer parameters.

In the optimum design of reinforced concrete (RC) structural members, the robustness of the employed method is important as well as solving the optimization problem. In some cases where the algorithm parameters are defined as non-effective values, local-optimum solutions may prevail over the existing global optimum results. Any metaheuristic algorithm can be effective to solve the optimization problem but must give the same results for several runs. Due to the randomization nature of these algorithms, the performance may vary with respect to time. The essential and novel work done in this study is the comparative investigation of 10 different metaheuristic algorithms and two modifications of harmony search (HS) algorithm on the optimum cost design of RC retaining walls constrained with geotechnical and structural state limits. The employed algorithms include classical ones (genetic algorithm (GA), differential evaluation (DE), and particle swarm optimization (PSO)), proved ones on structural engineering applications (harmony search, artificial bee colony, firefly algorithm), and recent algorithms (teaching-learning-based optimization (TLBO), flower pollination algorithm (FPA), grey wolf optimization, Jaya algorithm (JA)). The modifications of HS include adaptive HS (AHS) concerning the automatic change of algorithm parameters and hybridization of AHS with JA that is developed for the investigated problem. According to the numerical investigations, recent algorithms such as TLBO, FPA, and JA are generally the best at finding the optimum values with less deviation than the others. The adaptive-hybrid HS proposed in this study is also competitive with these algorithms, while it can reach the best solution by using a lower population number which can lead to timesaving in the optimization process. By the minimization of material used in construction via best optimization, sustainable structures that support multiple types of constraints are provided. Energy Cloud R&D Program through the National Research Foundation of Korea (NRF) - Ministry of Science, ICT [2019M3F2A1073164]; National Research Foundation of Korea (NRF) - Korea government (MSIT) [2020R1A2C1A01011131] This research was supported by the Energy Cloud R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT (2019M3F2A1073164). This work was also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2020R1A2C1A01011131).

Linux is a representative operating system running on many servers and password is the primitive authentication way. In this paper, we analyze the vulnerabilities of Linux password file management and show that it is possible to use spoofed attack using system administrator privileges. We also suggests countermeasures to prevent this.

The stacking sequence optimization of laminated composite plates while maximizing the structural performance or minimizing the weight is a subject investigated extensively in the literature. Meanwhile, research on the optimization of laminates with cut-outs has been relatively limited. Cut-outs being an indispensable feature of structural components, this paper concentrates on the stacking sequence optimization of composite laminates in the presence of circular cut-outs. The buckling load of a laminate is used as a metric to quantify the structural performance. Here the laminates are modeled as carbon fiber-reinforced composites using the finite element analysis software, ABAQUS. For the optimization, the widely used harmony search algorithm is applied. In terms of design variables, ply thickness, and fiber orientation angles of the plies are used as continuously changing variables. In addition to the stacking sequence, another geometric variable to consider is the aspect ratio (ratio of the length of the longer sides to the length of the shorter sides of the plate) of the rectangular laminates. The optimization is carried out for three different aspect ratios. It is shown that, by using dispersed stacking sequences instead of the commonly used 0 & DEG;/& PLUSMN;45 & DEG;/& PLUSMN;90 & DEG; fiber angle stacks, significantly higher buckling loads can be achieved. Furthermore, changing the cut-out geometry is found to have a significant effect on the structural performance. Energy Cloud R&D Program through the National Research Foundation of Korea (NRF) - Ministry of Science, ICT [2019M3F2A1073164] This research was supported by the Energy Cloud R & D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT (2019M3F2A1073164).

In this study, multi-story structures with different combinations (on each floor and only the first floor) of active tendon control systems driven by a proportional-integral-derivative (PID) controller were actively controlled. The PID parameters, K-p (proportional gain), T-d (derivative gain), and T-i (integral gain) for each structure, were optimally tuned by using both the harmony search algorithm (HS) and flower pollination algorithm (FPA), which are metaheuristic algorithms. In two different active-controlled structures, which are formed according to the position of the PID, the structural responses under near-fault records defined in FEMA P-695 are examined to determine the appropriate feedback which was applied for displacement, velocity, acceleration, and total acceleration. The performance of the different feedback strategies on these two active-controlled structures is evaluated. As a result, the acceleration feedback is suitable for all combinations of the active control system with a PID controller. The HS algorithm outperforms the optimum results found according to the FPA. National Research Foundation of Korea (NRF) - Korea government (MSIT) [2020R1A2C1A01011131]; Energy Cloud R&D Program through the National Research Foundation of Korea (NRF) - Ministry of Science, ICT [2019M3F2A1073164] This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2020R1A2C1A01011131). This research was also supported by the Energy Cloud R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT (2019M3F2A1073164).

In this paper, the Harmony Search (HS) algorithm is utilized to perform single and multivariate parametric studies to acquire the optimization of both size and cost of reinforced concrete (RC) retaining walls embedded in pure frictional soils. The geotechnical properties of the backfill and foundation soil such as shear strength angle, unit weight, and the ultimate bearing pressure of the soil have been used to create different cases for evaluating the effects of site properties on the size and cost of the wall. The change of depth of excavation and surcharge loading condition is fictionalized for generating different environmental conditions for all envisaged soil profiles to predict possible rates of influences. The unit cost of the concrete has also been evaluated as a variant to show the economic constraints on the selection of structural materials. The results of the analyses represent the integrated influences of different significant parameters on the achievement of minimum cost-dimension optimization. Besides, a well-known commercial geotechnical engineering software is used to compare the appropriateness of the suggested designs in terms of both the attainment of geotechnical stability and the structural requirements. Consequently, this study can guide both researchers and designers to select the proper and optimal sections of RC-retaining wall systems with simultaneous analyses of parameters that are influenced by the design process. Furthermore, the optimization results indicate that a significant cost reduction may be achieved when compared with the traditional pre-design method. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. Ministry of Science, ICT and Future Planning: 2019M3F2A1073164; National Research Foundation of Korea; Ministry of Science and ICT, South Korea: 2020R1A2C1A01011131 Funding: This research was supported by the Energy Cloud R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT (2019M3F2A1073164). This work was also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2020R1A2C1A01011131).

This paper investigates a method for obtaining a discriminative phoneme set extended by assigning a new label to acoustically ambiguous speech segments. The proposed method first extracts phoneme-level segments from a large amount of Korean broadcast data and then converts the variable-length segments into fixed-length vectors using the LSTM structure. Then, the fixed-length vectors belonging to each unit are used to generate a multivariate Gaussian model. Finally, we assign a new label to the samples located between the most overlapping Gaussian model pair, which is found by using the Jensen- Shannon divergence with the Monte-Carlo sampling. The above extension process is repeatedly performed until the desired number of units is reached. The newly assigned units constitute a new phoneme set used as the pronunciation dictionary. In broadcast news transcription experiments, we confirmed that the proposed method has the modest effect on discrimination by assigning a new label to the ambiguous speech samples.

The aim of the current article is to describe how to improve the quality of imaging with

We propose a method to extend a phoneme set by using a large amount of broadcast data to improve the performance of Korean spontaneous speech recognition. In the proposed method, we first extract variable-length phoneme-level segments from broadcast data and then convert them into fixed-length embedding vectors based on a long short-term memory architecture. We use decision tree-based clustering to find acoustically similar embedding vectors and then build new acoustic subword units by gathering the clustered vectors. To update the lexicon of a speech recognizer, we build a lookup table between the tri-phone units and the units derived from the decision tree. Finally, the proposed lexicon is obtained by updating the original phoneme-based lexicon by referencing the lookup table. To verify the performance of the proposed unit, we compare the proposed unit with the previous units obtained by using the segment-based k-means clustering method or the frame-based decision-tree clustering method. As a result, the proposed unit is shown to produce better performance than the previous units in both spontaneous, and read Korean speech recognition tasks.

Microplastics (MPs) of varying sizes are widespread pollutants in our environment. The general opinion is that the smaller the size, the more dangerous the MPs are due to enhanced uptake possibilities. It would be of considerably ecological significance to understand the response of biota to microplastic contamination both physically and physiologically. Here, we report on an area choice experiment (avoidance test) using Enchytraeus crypticus, in which we mixed different amounts of high-density polyethylene microplastic particles into the soil. In all experimental scenarios, more Enchytraeids moved to the unspiked sections or chose a lower MP-concentration. Worms in contact with MP exhibited an enhanced oxidative stress status, measured as the induced activity of the antioxidative enzymes catalase and glutathione S-transferase. As plastic polymers per se are nontoxic, the exposure time employed was too short for chemicals to leach from the microplastic, and as the microplastic particles used in these experiments were too large (4 mm) to be consumed by the Enchytraeids, the likely cause for the avoidance and oxidative stress could be linked to altered soil properties.

WOS:000756066300001 Performance of convergence to the optimum value is not completely a known process due to characteristics of the considered design problem and floating values of optimization algorithm control parameters. However, increasing robustness and effectiveness of an optimization algorithm may be possible statistically by estimating proper algorithm parameters values. Not only the algorithm which utilizes these estimated-proper algorithm parameter values may enable to find the best fitness in a shorter time, but also it may supply the optimum searching process with a pragmatical manner. This study focuses on the statistical investigation of the optimum values for the control parameters of the harmony search algorithm and their effects on the best solution. For this purpose, the Taguchi method integrated hybrid harmony search algorithm has been presented as an alternative method for optimization analyses instead of sensitivity analyses which are generally used for the investigation of the proper algorithm parameters. The harmony memory size, the harmony memory considering rate, the pitch adjustment rate, the maximum iteration number, and the independent run number of entire iterations have been debated as the algorithm control parameters of the harmony search algorithm. To observe the effects of design problem characteristics on control parameters, the new hybrid method has been applied to different engineering optimization problems including several engineering-optimization examples and a real-size engineering optimization design. End of extensive optimization and statistical analyses to achieve optimum values of control parameters providing rapid convergence to optimum fitness value and handling constraints have been estimated with reasonable relative errors. Employing the Taguchi method integrated hybrid harmony search algorithm in parameter optimization has been demonstrated as it is a reliable and efficient manner to obtain the optimum results with fewer numbers of run and iteration.

Purpose This paper aims to examine the merit of an indirect payment system for audit fees, a system where an intermediary collects fees from the auditee and then pays this audit fee to the auditor. Design/methodology/approach Big 4 auditors and professional analysts in South Korea participated in an experiment and survey to investigate whether the change in the payment channel (from direct to indirect) of audit fees positively impacts auditors’ decision-making. Findings The authors find evidence that the indirect payment of audit fees is positively associated with professional skepticism. Research limitations/implications This paper, by highlighting the potential for alternate auditor payment channels to improve the quality of auditor judgments, motivates future research in this area. Practical implications Qualified by the need for further research, the potential merit in an indirect payment system may have implications for audit regulators. Social implications An indirect payment channel has the potential to improve public perceptions of the audit function, thereby elevating society’s confidence in auditor opinions and improving the effectiveness and efficiency with which scarce resources are distributed within society. Originality/value This study is one of the first that looks into a systematic change in audit fee payment channel and how an indirect payment system of audit fees impacts professional skepticism.

The antibacterial efficacy of UV–TiO2 photocatalysis pre-washing in a water-assisted system (UVT, 4.5 mW/cm2, 5–15 min) and high hydrostatic pressure (HHP, 300–500 MPa, 1 min at 25 °C) post-package combined treatment was evaluated against Salmonella Typhimurium inoculated onto whole cherry tomato surfaces and compared with chlorine disinfection (200 ppm). An air pump was fitted at the bottom of UVT reactor to create turbulent flow for rotation of fruits for uniform disinfection. UVT–HHP combined treatment at 500 MPa achieved bacterial reduction of more than 5 log via a synergistic effect, compared with chlorine disinfection. Lycopene and total phenolic contents and antioxidant activities were not significantly changed in tomatoes after any treatment. UVT–HHP combined treatment did not affect the surface color but caused softness in tomatoes. UVT pre-washing followed by HHP post-package treatment can be the effective intervention strategy alternative to conventional chlorine disinfection for production of ready-to-eat (RTE) fresh cherry tomatoes.

Air conditioning in an electric car significantly impairs its driving range. This study intends to save energy consumed by air conditioning in cars while maintaining a similar level of the thermal environment in the cabin. The cooling load is removed by controlling the air temperature by an evaporator. Conventional feedback controllers only counteract errors with phase delay. To control the temperature and also save energy, model predictive control is proposed with an optimization algorithm of quadratic programming. Vehicle tests cost too much to be conducted frequently for the development of predictive control. To replace vehicle tests, a dynamic refrigeration cycle is developed as a high fidelity simulator, and its performance is verified against vehicle tests. The error dynamics of the air temperature are developed as a first order system, and linear approximation of the compressor power with a decision variable is proposed to establish a linear constraint that is necessary for the optimization formulation. The algorithm tested with the simulator leads to an energy savings of 2.65% while maintaining a similar level of temperature control by use of conventional feedback control.

Dynamic voltage restorer (DVR) technology has become a mature power quality product. In high-power applications, DVR using a multilevel converter is commonly used. However, DVR using a multilevel direct pulse width modulation (PWM) ac–ac converter has not been well studied. This paper presents a new DVR topology using a cascaded multilevel direct PWM ac–ac converter. In the proposed scheme, the unit cell of the multilevel converter consists of a single-phase PWM ac-ac converter using switching cell structure with coupled inductors. Therefore, the multilevel converter can be short- and open-circuited without damaging the switching devices. Neither lossy RC snubber nor a dedicated soft commutation strategy is required in the proposed DVR. This improves the reliability of the DVR system. The output voltage levels of the multilevel converter increase with the number of cascaded unit cells, and a high ac output voltage is obtained by using low-voltage-rating switching devices. Furthermore, a phase-shifted PWM technique is applied to significantly reduce the size of the output filter inductor. A 1-kW prototype of single-phase DVR is developed, and its performance is experimentally verified. Finally, the simulation results are shown for a three-phase DVR system.

Vehicles have come to be regarded as another important indoor environment where people spend a significant amount of time. Along with the accelerated development of self-driving vehicles, more attention has been focused on optimizing the thermal comfort of vehicle users. Compared with buildings, vehicles have a non-uniform indoor environment that dynamically changes under the influence of solar radiation and the season of the year. Considering the various environmental factors that significantly impact the indoor condition of a vehicle, it is very challenging to estimate the thermal comfort of a vehicle user, especially when the vehicle is outdoors. Many comfort models have been developed based on subject experiments conducted using vehicles placed in climatic chambers. However, because such laboratory experiments consider only very limited conditions, a dynamic scene that simulates the actual situation of vehicle users under real driving conditions cannot be implemented. To address this issue, the present study utilized long-term outdoor experiments. Based on the data acquired from the experiments, we derived equations for predicting the overall thermal sensation (OTS) of a female vehicle user under both transient and stable conditions. The field experiments were conducted over three seasons and considered a total of 80 female subjects of ages 20–30 years. All the experiments were performed using an experimental vehicle on the rooftop of a seven-story building, where the sunlight was not shielded. The environmental conditions (air temperature, relative humidity, solar radiation, and air velocity) inside and outside the vehicle were measured. The psychological and physiological responses of the subjects during the experiments were also recorded. The physiological responses consisted of the skin temperature at 16 local body sites, while the psychological responses consisted of the local and overall thermal sensation and comfort. The data of 60 randomly selected subjects of the experiments were used to derive optimal multiple regression equations for predicting the OTS of a female vehicle user, while the data of the other 20 subjects were used to validate the proposed equations. The two derived equations of the OTS prediction model for both non-uniform and uniform state of a vehicle consist of simple and straightforward environmental indicators such as outdoor and indoor air temperature, the difference between the outdoor and indoor air temperature, and the solar radiation. A strong correlation between the actual OTS and predicted OTS from the equations were found, showing the feasibility of the developed OTS prediction model.

The cybersecurity industry is continuing to grow in workforce participation due to the growing popularity of its services in both commercial and government organizations. The government has recognized and created several frameworks that outline the work role standards for the multiple sectors. A comparison of these frameworks would not only provide a perspective of the purpose for maintaining different frameworks, but also provide a model of their relationships and the sectors that they cover. This paper will compare frameworks, outline the differences and similarities among them, and suggest ways to promote the workforce participation even more.

In this paper, we suggest a basic topical model(TM) framework to adapt speech recognition system to multi-domain and prevent topical errors. This paper employs the cosine similarities between target and context words at a spoken utterance as the topical model parameters. The TM is applied to frames having a large number of candidate words at lattice network, and it adjusts the ranking of candidate words by adding it to total cost estimated from acoustic model(AM) and language model(LM). To cover multidomain, the word embedding was trained with 5.5 billion text corpus from multi-domain. As an acoustic model and a language model, DNN-HMM and $N$ - gram were selected. 501 sentences (10,054 words) includes 35 topics were used as an evaluation data set. As a result, the best performances were obtained by our approach, and the performance of WERR was increased up to about 4% compared with $N$ -gram based model. The WERR increased above 10% when the word errors were correctly detected. The results show this suggestion has a possibility of adapting a model to multi-domains without sub-topic models.

Endocrine active compounds with structural similarities to natural hormones such as 17&beta, estradiol (E2) and androgen are suspected to affect the human endocrine system by inducing hormone-dependent effects. This study aimed to detect the (anti-)estrogenic and (anti-)androgenic activities of mono-(2-ethylhexyl) phthalate (MEHP) by yeast estrogen/androgen bioassay (YES/YAS). In addition, the mechanism and uptake of MEHP to receptors during agonistic and antagonistic activities were investigated through the activation signal recovery test and chromatographic analysis using liquid chromatography and tandem mass spectrometry (LC-MS/MS). Estrogenic and androgenic activities of MEHP were not observed. However, MEHP exhibited anti-estrogenic (IC50 = 125 &mu, M) and anti-androgenic effects (IC50 = 736 &mu, M). It was confirmed that these inhibitory effects of MEHP were caused by receptor-mediated activity of the estrogen receptor and non-receptor-mediated activity of the androgen receptor in an activation signal recovery test. When IC50 concentrations of anti-estrogenic and androgenic activity of MEHP were exposed to yeast cells, the uptake concentration observed was 0.0562 &plusmn, 0.0252 &mu, M and 0.143 &plusmn, 0.0486 &mu, M by LC-MS/MS analysis.

In this paper, a novel dual output dual-active-bridge (DAB) converter with output voltage balancing is proposed. The proposed circuit is similar in structure with conventional DAB converter, but a balancing inductor is added in between the transformer secondary winding and midpoint of dual outputs to balance the two output voltages. As conventional DAB converter, it is operated with phase-shifted pulse-width-modulation control. Although a balancing inductor is added, it does not affect the operation mode significantly. Therefore, the proposed converter retains most of the characteristics of the conventional DAB converter. Although the proposed converter has slightly increased secondary switch current due to the balancing inductor, it achieves balanced output voltages without additional switching devices. A 2.7 kW prototype converter is built and tested to verify the performances of the proposed converter.

Integrated biochemical sensors based on Mach-Zehnder interferometers (MZIs) rely on the evanescent field detection principle to monitor the phase shift induced by a refractive index change on the surface of the sensing arm, providing a high sensitivity thanks to the long interaction length with the analyte. This paper presents an integrated refractive index and biochemical sensor based on a pair of balanced MZIs realized on silicon-on-insulator. The device includes a thermal phase modulator in one of the branches of each MZI to extract univocally the induced phase change by applying active phase detection based on the phase generated carrier technique. The direct modulation of the MZI results in a simple configuration of the sensor, only requiring a fixed wavelength laser and a photodetector, enabling the possibility of full monolithic integration. The results of refractive index measurements show a detection limit down to 4.88 × 10–7 RIU. Additionally, an immunoassay reports the binding of anti-bovine serum albumin (BSA) to BSA, with anti-BSA concentrations down to 33.33 nM.

Total Potential Optimization using Metaheuristic Algorithms (TPO/MA) is an alternative tool for the analysis of structures. It is shown that this emerging method is advantageous in solving nonlinear problems like trusses, tensegrity structures, cable networks, and plane stress systems. In the present study, TPO/MA, which does not need any specific implementation for nonlinearity, is demonstrated to be successfully applied to the analysis of plane strain structures. A numerical investigation is performed using nine different metaheuristic algorithms and an adaptive harmony search in linear analysis of a structural mechanics problem having 8 free nodes defined as design variables in the minimization problem of total potential energy. For nonlinear stress-strain relation cases, two structural mechanics problems, one being a thick-walled pipe and the other being a cantilever retaining wall, are analyzed by employing adaptive harmony search, which was found to be the best one in linear analyses. The nonlinear stress-strain relations considered in these analyses are hypothetical ones due to the lack of any such relationship in the literature. The results have shown that TPO/MA can solve nonlinear plane strain problems that can be encountered as engineering problems in structural mechanics. Energy Cloud R&D Program through the National Research Foundation of Korea (NRF) - Ministry of Science, ICT [2019M3F2A1073164]; National Research Foundation of Korea (NRF) - Korea government (MSIT) [2020R1A2C1A01011131] This research was supported by the Energy Cloud R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT (2019M3F2A1073164). This work was also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2020R1A2C1A01011131).

New AD-based denoising method using adaptive smoothing strength is proposed.Many classifiers are used to consider the varying noise characteristics.Training data are filtered to obtain balanced training results.Simple region analysis metric is proposed. This paper presents an improved anisotropic diffusion method using region adaptive smoothing strength. Unlike existing methods, the proposed method uses an adaptive classifier to find a good estimate of the optimal smoothing strength for each iteration to consider the varying noise characteristics. Further, when training the classifiers, the usefulness of the training data is verified and less useful data are excluded to avoid degraded training results, thereby generating robust and improved denoising performance. For reduction of the computational complexity, this paper also proposes a simple region analysis technique. Consequently, the proposed method is appropriate for the devices that have relatively small computing power. Experimental results confirm that the proposed method outperforms AD-based benchmark methods by increased peak signal-to-noise ratio up to 2.37dB and structural similarity up to 0.0557 for 10% noise level.

Objectives: Materials coming into contact with food may result in the migration of chemical substances into the food. To protect consumers from exposure, Regulation (EU) No. 10/2011 specifies the use of standard migration tests. Polyethylene terephthalate (PET), widely used for food packaging materials, has drawn the attention of researchers because unwanted migration of PET into food might occur when consumers reuse packaging material. The aim of this study was to predict and develop a migration model for two components, acetaldehyde and butyraldehyde in PET, into food simulants under conditions of changing pH and solvents, such as those observed in fermented foods like kimchi or sauerkraut. Methods: Using a migration model based on Fick’s second law of diffusion in one dimension, the migration of acetaldehyde and butyraldehyde from PET into a simulant of fermented food at 20 ℃ over 10 days was evaluated. The simulant for fermented food was modelled as 10% ethanol for three days, followed by 3% acetic acid for seven days. Results: The migration of acetaldehyde into the 10% ethanol was 0.36 times that of a simulated fermented food system, while that of butyraldehyde was 1.34 times greater. These results may have been influenced by the chemical interactions among the migrants, polymers and simulants, as well as by the solubilities of the migrants in polymers and simulants. Conclusion: Because food simulants have a limited capacity to mimic real food systems under the current migration model, an appropriate simulant and migration test should be considered in the case of increasing acidity. Furthermore, since the accuracy of the worst-case estimation of migration predicted by the current model is severely limited under changing food conditions, food simulants and their interactions should be further investigated with respect to conservative migration modelling.

This paper presents an accurate real-time stereo matching method, which is based on the extended binary weighted aggregation. The accuracy of the proposed stereo matching method was significantly enhanced by extending its binary weighted aggregation so that remote connections of support regions can be allowed for aggregation. The extended binary weighted aggregation is based on the following two new ideas. First, the extended binary weighted aggregation connects distant regions over color boundaries, making them one large support region for a given pixel. This approach induces more aggregation targets, and, thus, makes the aggregation step more robust. Second, it excludes cost outliers in the support region to prevent them from being propagated during the aggregation step, making a quality support region. With the extended binary weighted aggregation, the proposed stereo matching method obtains more accurate disparity maps than existing stereo matching methods using binary weighted aggregation methods, while maintaining the speed advantage of binary weighted aggregation. Experimental results illustrated that the proposed stereo matching method outperformed all existing real-time stereo matching methods in terms of accuracy, providing the average bad pixel rate of 5.12%, for the Middlebury stereo test images. The proposed stereo matching method was implemented on a CUDA platform with a high-end GPU. The implemented system operated at up to 300 fps for the stereo images with 320 × 240 pixel resolution and a disparity range of 32 pixels.

A high fidelity refrigeration cycle simulator was developed using the moving boundary method and the simulator's performance was confirmed with test data of a household air conditioner. The simulator showed a good agreement with the test data. The simulator was applied as a virtual test bed to generate normal and faulty operation data which were needed to develop FDD algorithm. To evaluate the feasibility of the simulator for FDD development, a typical time-varying cooling load was generated and normal and faulty cases were simulated. Steady state filter was constructed from moving average and standard deviation. Evaporator fouling was diagnosed by comparing estimated UA at a given fan speed with normal UA at the same fan speed. Superheat cannot be controlled when an EEV gets stuck. Time-integrated superheat error was found to be a good indicator to detect the fault.

The shear buckling of web plates and lateral&ndash, torsional buckling are among the major failure modes of plate girders. The importance of the lateral&ndash, torsional buckling capacity of plate girders was further evidenced when several plate girders of a bridge in Edmonton, Alberta, Canada failed in 2015, because insufficient bracing led to the lateral buckling of the plate girders. In this study, we focus on the optimisation of the cross-sections of plate girders using a well-known and extremely efficient meta-heuristic optimisation algorithm called the harmony search algorithm. The objective of this optimisation is to design the cross-sections of the plate girders with the minimum area that satisfies requirements, such as the lateral&ndash, torsional buckling load and ultimate shear stress. The base geometry, material properties, applied load and boundary conditions were taken from an experimental study and optimised. It was revealed that the same amount of load-carrying capacity demonstrated by this model can be achieved with a cross-sectional area 16% smaller than that of the original specimen. Furthermore, the slenderness of the web plate was found to have a decisive effect on the cost-efficiency of the plate girder design.

In dc microgrid, a bipolar dc bus configuration has more merits than an unipolar one, due to higher reliability, easy grounding, and having more voltage levels. However, tight voltage balancing control is necessary to handle unbalanced power between positive and negative buses. To solve this issue effectively, this paper proposes a new voltage balancer with dc-dc converter function. The proposed balancer can serve as both a voltage balancer and a bidirectional dc-dc converter. Thus, it can be applied to battery management system or fast charger in electric vehicles (EVs) charging station while balancing the bipolar dc bus voltages. Unlike the conventional voltage balancing control using a three-level dc-dc converter, the voltage balancing range of the proposed system is not limited. To confirm this superiority, a comparison of the voltage balancing range between the proposed and conventional scheme is explored. Simulation and experimental results are provided in order to validate the effectiveness of the proposed system.

A cascaded dual-buck ac-ac converter (CDBAC) possesses no shoot-through worries, no commutation problem, and can enhance efficiency by using power MOSFETs. The main drawback of a CDBAC is the use of more inductors than traditional cascaded multilevel ac-ac converter, which decreases the power density and increases the system cost. This paper presents a modified CDBAC using coupled inductors. In the proposed converter, the limiting inductors connected between units are integrated with one core. Because they share the current path where output inductor current is flowing. As a result, the total inductance, inductor footprints, and magnetic volume can all be reduced. To demonstrate the advantages of the proposed converter, the topology derivation, operation, and experimental results are presented.

The antibacterial efficacy of UV–TiO(2) photocatalysis pre-washing in a water-assisted system (UVT, 4.5 mW/cm(2), 5–15 min) and high hydrostatic pressure (HHP, 300–500 MPa, 1 min at 25 °C) post-package combined treatment was evaluated against Salmonella Typhimurium inoculated onto whole cherry tomato surfaces and compared with chlorine disinfection (200 ppm). An air pump was fitted at the bottom of UVT reactor to create turbulent flow for rotation of fruits for uniform disinfection. UVT–HHP combined treatment at 500 MPa achieved bacterial reduction of more than 5 log via a synergistic effect, compared with chlorine disinfection. Lycopene and total phenolic contents and antioxidant activities were not significantly changed in tomatoes after any treatment. UVT–HHP combined treatment did not affect the surface color but caused softness in tomatoes. UVT pre-washing followed by HHP post-package treatment can be the effective intervention strategy alternative to conventional chlorine disinfection for production of ready-to-eat (RTE) fresh cherry tomatoes.

Summary Sikhye is a popular Korean rice-and-malt drink. This drink is prepared using a specific traditional process and has short shelf life. Commercial processing using ultra-high temperature affects characteristic colour and flavour attributes and disturbs the traditional method of sikhye preparation. The objective of this study was to compare the effect of TiO2–UVC photocatalysis (TUVP) nonthermal processing with heat-pasteurised and untreated sikhye samples during storage at 4 and 10 °C. TUVP and heat treatments were both sufficient to inhibit regrowth of total aerobic bacteria and coliform during storage. Hunter colour parameter values showed that the colour of sikhye was less affected by TUVP treatment compared to the heat treatment. Higher sensory scores for flavour, taste and overall preference were attained for low-dosage TUVP-treated (0.24 J cm−2) samples than for heat-treated samples but without a significant difference. TUVP treatment effectively controlled the microbial growth during storage at 4 °C for more than 18 days which was reported a serious microbiological safety issue. In summary, TUVP showed its suitability for commercialisation possibilities of fresh sikhye drink by inactivating the main micro-organisms and thus increasing significantly its shelf life with minimum impact on quality characteristics.

We analyze objects and methods required for checking automated design compliance.We analyze 27 RFPs for various types of large public buildings in South Korea.Only 14% of over 9800 RFP sentences are analyzed as being computer-interpretable.Three types of objects and 29 types of methods are derived.The sufficiency of the objects and methods is validated using additional RFPs. This study reports on the requirements for developing computer-interpretable rules for checking the compliance of a building design in a request for proposal (RFP), especially in the building information modeling (BIM) environment. It focuses on RFPs for large public buildings (over 5million dollars) in South Korea, which generally entail complex designs. A total of 27 RFPs for housing, office, exhibition, hospital, sports center, and courthouse projects were analyzed to develop computer-interpreted RFP rules. Each RFP was composed of over 1800 sentences. Of these, only three to 366 sentences could be translated into a computer-interpretable sentence. For further analysis, this study deployed context-free grammar (CFG) in natural language processing, and classified morphemes into four categories: i.e., object (noun), method (verb), strictness (modal), and others. The subcategorized morphemes included three types of objects, twenty-nine types of methods, and five levels of strictness. The coverage applicability of the derived objects and methods was checked and validated against three additional RFP cases and then through a test case using a newly developed model checker system. The findings are expected to be useful as a guideline and basic data for system developers in the development of a generalized automated design checking system for South Korea.

A novel optimization approach for reinforced concrete (RC) biaxially loaded columns is proposed. Since there are several design constraints and influences, a new computation methodology using iterative analyses for several stages is proposed. In the proposed methodology random iterations are combined with music inspired metaheuristic algorithm called harmony search by modifying the classical rules of the employed algorithm for the problem. Differently from previous approaches, a detailed and practical optimum reinforcement design is done in addition to optimization of dimensions. The main objective of the optimization is the total material cost and the optimization is important for RC members since steel and concrete are very different materials in cost and properties. The methodology was applied for 12 cases of flexural moment combinations. Also, the optimum results are found by using 3 different axial forces for all cases. According to the results, the proposed method is effective to find a detailed optimum result with different number of bars and various sizes which can be only found by 2000 trial of an engineer. Thus, the cost economy is provided by using optimum bars with different sizes.

Few-layer tungsten diselenide (WSe2) is investigated using circularly polarized Raman spectroscopy with up to eight excitation energies. The main E2g1 and A1g modes near 250 cm-1 appear as a single peak in the Raman spectrum taken without consideration of polarization but are resolved by using circularly polarized Raman scattering. The resonance behaviors of the E2g1 and A1g modes are examined. Firstly, both the E2g1 and A1g modes are enhanced near resonances with the exciton states. The A1g mode exhibits Davydov splitting for trilayers or thicker near some of the exciton resonances. The low-frequency Raman spectra show shear and breathing modes involving rigid vibrations of the layers and also exhibit strong dependence on the excitation energy. An unidentified peak at ~19 cm-1 that does not depend on the number of layers appears near resonance with the B exciton state at 1.96 eV (632.8 nm). The strengths of the intra- and inter-layer interactions are estimated by comparing the mode frequencies and Davydov splitting with the linear chain model, and the contribution of the next-nearest-neighbor interaction to the inter-layer interaction turns out to be about 34% of the nearest-neighbor interaction. Fano resonance is observed for 1.58-eV excitation, and its origin is found to be the interplay between two-phonon scattering and indirect band transition., 45 pages, 20 figures (including Supplementary Information)