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In the post and beam structure, the post and beam play a crucial role in directly supporting and transmitting loads, thus making them essential elements in structural design. In cases where the moment resistance performance of the post-beam joint is inadequate, a shear wall and bracing are frequently installed to provide support for horizontal load on the posts and beams. The structural insulated panel (SIP) is increasingly utilized and studied as shear walls alongside light-frame timber construction, owing to its insulation properties as well as its high shear strength. In this study, when using SIP as a shear wall between post and beams, three composite wall structures were considered based on the installation location of the SIPs on the post-beam structure and lateral resistance performance of the hybrid shear wall was evaluated according to the SIP installation location. Depending on the installation location SIPs on the posts and beams, shear strength for I-SIP 150, E-SIP 150, and M-SIP 150 were 23.2, 24.6, and 26.0 kN, respectively. In case of the shear stiffness, I-SIP 150, E-SIP-150, and M-SIP 150 were found to be 4.32, 3.99, and 2.74 kN/mm, respectively.

This study aimed to enhance the thermal efficiency of the sulphitation process in the boiling house of sugar plants using a combined approach of pinch and exergy analyses. Pinch analysis is a reliable method for optimizing the design of energy recovery systems. However, the primary limitations arise from its exclusive focus on heat transfer processes. On the other hand, exergy balance provides valuable insight into the consumption of supplied exergy by individual process units, serving as a quantitative measure of inefficiency. The boiling house was evaluated and modified using pinch-exergy analysis with Sulphitation Process capacity production of 8000 TCD. The results showed a potential reduction in exergy destruction by approximately 10.25 MW. The optimization effort led to reductions of 18.18 and 14.70% in the use of hot and cold external utility, respectively.

The shear resistance of a structural particleboard (PB) wall was evaluated as a means to utilize recycled wood and low-grade logs for long periods. The wall was composed of spruce-pine-fir (SPF) lumber, nails, and structural PB, which was developed by improving the water resistance of default PB. Structural PB has a higher density than OSB, which is a commonly used covering material for light wooden structural walls, so a longer end distance for nailing at edge of sheathing is needed for structural PB. In this study, it was confirmed that structural PB walls sufficiently resisted lateral load when the end distance was 15 mm. In this case, the shear strength, shear modulus, and ductility of the structural PB wall for lateral cyclic load were confirmed as 9.2 kN/m, 2.0 kN/mm, and 6.2, respectively. When compared to the design value, the shear strength value was higher than that of the OSB wall and the plywood wall. The shear modulus was lower than that of OSB walls, but higher than plywood walls. Based on the above results, it was considered that structural PB light-frame wall could be used in residential load-bearing applications.

The recent focus on greenhouse gas emissions from fossil fuel usage has led to strengthened regulations on carbon emissions. Consequently, research on electric vehicles (EV), which have higher energy efficiency compared to internal combustion engine vehicles, is actively being pursued. With advancements in the technology of electronic components in electric vehicles, there is a growing trend in the demand for higher-rated capacities of Low DC-DC Converter (LDC) that possess a wide input-output voltage range. Furthermore, the restricted space within vehicles and the emphasis on high energy utilization necessitate converters with high power density and efficiency. Currently, in electric vehicles, the Active Clamp Forward Converter (ACFC) and the Phase Shift Full-Bridge Converter (PSFB) are commonly applied, as they readily achieve a wide input-output voltage range and high power density. However, ACFC and PSFB encounter difficulties in achieving high efficiency and power density due to the requirement for output inductors with high current specifications. To address these challenges, this study proposes a Two-Transformer Phase Shift Full-Bridge Converter (2-TR PSFB) based on planar transformers, which can replace conventional ACFC and PSFB. The proposed converter achieves high efficiency and power density without the need for high-current output inductors. Additionally, the utilization of GaN power semiconductors allows for a high switching frequency, enabling a significant reduction in the volume of magnetic components. This research presents the operational principles of the 2-TR PSFB and provides design directions. To validate the design, a 2.5 kW prototype was manufactured and tested.

This paper proposes a model predictive control with space vector modulation (MPC-SVM) method that is based on using a voltage angle to reduce ripple components in open-end winding interior permanent magnet synchronous motor (OEW-IPMSM). Conventional model predictive control (CMPC) provides fast transient states by applying an actual voltage vector each switching period. However, due to the limited magnitude of voltage vectors, the CMPC causes large torque ripple and low current quality. The MPC-SVM method proposed herein generates virtual voltage vectors based on the voltage angle and surrounding area. Virtual voltage vectors provide various magnitudes and positions except for areas that are not in use. The optimal reference voltage vector is derived as the result of the cost function operation applied through the space vector modulation (SVM) method, and it improves the steady-state compared to the CMPC. Therefore, torque ripple is reduced and current quality is improved by using fewer virtual voltage vectors, and this results in superior steady-state characteristics. The validity of the proposed MPC-SVM method based on the voltage angle for driving OEW-IPMSM is affirmed through simulation and experimental results in comparison to the CMPC.

In the past, the occurrence of macro alga Ulva lactuca on the coastal areas of Jeju Island, Korea, has resulted in the expansion of devastating green tides, thus affecting coastal sustainability, aesthetic appearances, and tourism activities. Taking consideration of the above scenario, substantial economic costs are required for the environmental protection of the island, and it is highly recommended to employ Ulva lactuca in an alternative useful way. Hence, this paper proposes a new strategy to utilize Ulva lactuca as a tribopositive layer in a triboelectric nanogenerator (TENG). Based on the coastal bio-waste Ulva lactuca, the fabricated TENG device generates a maximum output voltage of 875 V, output current of 52 μA, and power density of 272.72 μW/cm2. Furthermore, the device presents excellent cyclic stability with no degradation in the output voltage even after 10000 consecutive cycles at a frequency of 2 Hz. The proposed TENG is further employed to charge the various commercially available capacitors, lightning LEDs, power stopwatches, and scavenge energy from body motions. It is anticipated that the proposed TENG device will pave a new way towards Ulva lactuca management for sustainable energy harvesting and clean coastlines.

With increasing worries about the environment, there is a rising focus on saving energy in various industries. In the e-mobility industry of electric motors, permanent magnet synchronous motors (PMSMs) are widely utilized for saving energy due to their high-efficiency motor technologies. However, challenges like environmental degradation from rare earth development and difficulties in controlling magnetic field fluctuations persist. To address these issues, active research focuses on the wound field synchronous motor (WFSM), known for its ability to regulate field current efficiently across various speeds and operating conditions. Nevertheless, compared with other synchronous motors, the WFSM tends to exhibit relatively lower efficiency and torque density. Because the WFSM involves winding both the rotor and the stator, it results in increased copper and iron losses. In this article, a model that enhances torque density by inserting permanent magnets (PMs) into the rotor of the basic WFSM is proposed. This proposed model bolsters the d axis magnetic flux, thereby enhancing the motor’s overall performance while addressing environmental concerns related to rare-earth materials and potentially reducing manufacturing costs when compared with those of the PMSM. The research methodology involves a comprehensive sensitivity analysis to identify key design variables, followed by sampling using optimal Latin hypercube design (OLHD). A surrogate model is then constructed using the kriging interpolation technique, and the optimization process employs a micro-genetic algorithm (MGA) to derive the optimal model configuration. The algorithm was performed to minimize the use of PMs when the same torque as that of the basic WFSM is present, and to reduce torque ripple. Error assessment is conducted through comparisons with finite element method (FEM) simulations. The optimized permanent-magnet-assisted WFSM (PMa-WFSM) model improved efficiency by 1.08% when it was the same size as the basic WFSM, and the torque ripple decreased by 5.43%. The proposed PMa-WFSM derived from this article is expected to be suitable for use in the e-mobility industry as a replacement for PMSM.

Advanced molecular approaches and continuous surveys in subtidal areas have contributed to improvements in red algal diversity, especially Gigartinales, Halymeniales, and Rhodymeniales. With deep subtidal collection along the Korean coast and molecular analyses in the plastid rbcL region, we resolved three new florideophycean species and a new record of Korean macroalgal list: Chrysymenia barimifolia sp. nov. in Rhodymeniales; Galene scutae sp. nov. in Halymeniales; and Psaromenia stipitata sp. nov. and Turnerella pennyi in Gigartinales. C. barimifolia sp. nov., which is monophyly supported strongly in the phylogenetic analysis, has an iridescent blade in natural habitat uniquely. G. scutae sp. nov. is singly grown and has thin and stiff blades arising from a very short and cylindrical stipe without midrib. P. stipitata sp. nov. has a single, erect, foliose, and membranous blade with pink color. Finally, Korean T. pennyi specimens form a clade with specimens from the species type locality, the Arctic region of Canada, with 1.8% genetic divergence. These four new members from deep subtidal enrich our knowledge of Korean macroalgal flora and help us to understand the vertical distribution of red algal species along Korean coastlines expanded.

This paper presents optimal rotor permanent magnet (PM) and rotor pole-piece skew to improve the total harmonic distortion (THD) of the back electromotive force (Back-EMF) in magnetic geared permanent magnet synchronous motor (MG-PMSM) for traction. MG-PMSM is a system that integrates a magnetic gear and a PMSM which can minimize the size of the driving system and reduce power loss because there is no mechanical friction unlike the existing motor. For this reason, it is more advantageous in terms of output density and efficiency. However, MG-PMSM has a pole-piece rotor for magnetic flux modulation, which can produce additional spatial harmonics in back electromotive force (back-EMF). In addition, this motor has inevitable to have a salient permanent magnet structure for the stator due to magnet loss, and in the case of winding methods, fractional slot concentrated winding (FSCW) is mainly used, which also causes additional harmonics. THD in back-EMF adversely affects torque ripple and make accurate position control difficult. Therefore, in this paper, THD in back-EMF is reduced by focusing on the optimal rotors skew. Considering the characteristics of MG-PMSM, skew is applied to each rotor, and then compared and analyzed with the proposed model.

This paper proposes an advanced discontinuous pulse-width modulation (DPWM) scheme for a dual inverter to reduce switching loss. A dual inverter is used to drive an open-end winding interior permanent magnet synchronous motor (OEW-IPMSM). It is composed of double two-level inverters with large switching loss owing to the use of 12 switching devices. When a current phase changes, the switching loss cannot be minimized by using a conventional DPWM scheme. As the conventional DPWM scheme uses reference voltage for switching, the switching loss cannot be minimized due to the difference between the phases of the stator current and phases of reference voltages. However, the proposed DPWM scheme with additional calculations of the current phase can minimize switching loss. When the current phase changes, the proposed DPWM is switched to ±30° of the maximum point of the current. Furthermore, the effectiveness of the proposed switching loss reduction ability is verified through simulations and experimental results.

Scholars have believed that motivation crowding out will occur when performance-based personnel management is practiced in the public sector. However, drawing on a more sophisticated typology of human motivation, this study demonstrates that the provision of extrinsic rewards can motivate, rather than demotivate, public employees even if public employees have strong public service motivation. Analyzing the data from the Federal Employee Viewpoint Survey (USA), this study found that the practice of employee performance management increases work effort and job satisfaction, and that such effects were mediated mainly by the hybrid motivational mechanisms (i.e., via enhanced self-concepts and perceived fairness), rather than by increasing sheer extrinsic motivation. This implies that the practice of employee performance management can be effective in motivating public employees.

Objectives: The purpose of this study is to comprehensively review Korean domestic stud-ies and investigate the research trends of pharmacopuncture therapy on cervical pain caused by traffic accidents. Methods: Domestic studies between February 1999 and May 2020 from four Korean databases were searched with combinations of keywords ‘cervical pain’, ‘traffic accident’, ‘whiplash injury’, and ‘pharmacopuncture’.Results: 17 studies were selected for review, including 7 randomized controlled trials, 5 retrospective observational studies, 3 case reports, and 2 non-randomized controlled trials. Each study was reviewed by published year, study type, types of pharmacopuncture solu-tions, selected acupuncture points, dosage of pharmacopuncture solutions, frequency of treatment, concurrent treatments, outcome measurements, and the effectiveness of phar-macopuncture therapy. The results are as follows: (1) It showed that the total number of published studies had increased slightly in the last 10 years compared to the previous de-cade. (2) The pharmacopuncture solutions used in the studies were in the following order: Bee-Venom (蜂毒), Jungsongouhyul (中性瘀血), Hwangryunhaedoktang (黃連解毒湯) and Soyeom (消炎). Frequently used acupuncture points were GB20, GV21, A-shi point, GV16, EX-B2, and SI15 in order. (3) The most commonly used total injection dosage was 1.0 cc at a time, and the frequency of treatment was twice a week. (4) Concurrent treatments such as acupuncture, herbal medication, physical therapy and Chuna manual therapy were per-formed in all 17 studies. (5) Pharmacopuncture therapy showed positive effects on cervical pain caused by traffic accidents in all 17 studies reviewed.Conclusion: Pharmacopuncture therapy was effective in cervical pain caused by traffic ac-cidents in all 17 studies selected. Further studies will be needed using more larger scales and more objective data to confirm the effectiveness of pharmacopuncture therapy and to generalize its application.

Many have expected that performance management will enhance the motivation of public employees. However, studies have reported that the motivational effect was minimal. This study examines whether the motivational impact can be enhanced by exerting transformational and transactional leadership. The analysis of the 2013 Federal Employee Viewpoint Survey reveals that while transformational leadership has a positive main effect on motivation, transactional leadership did not do so. As for moderator analysis, it indicates that transactional leadership has a positive moderating effect on the relationship between performance management on motivation, while transformational leadership does not. These results indicate that leadership makes significant differences in the motivational effect of performance management and that transactional leadership and transformational leadership influence worker motivation in distinctive ways. Hence, managers need to strike a balance between exerting transformational and transactional leadership to motivate people effectively in the era of performance management.

The marine red algal order Halymeniales currently includes two families, the Halymeniaceae and Tsengiaceae, and consist of 38 genera and about 358 species. Phylogenetic analyses on specific taxa of the order are common, but not comprehensive, leaving the many intra-ordinal relationships within the Halymeniales unresolved. To reassess the phylogeny of the Halymeniales, we conducted extensive phylogenetic analyses based on 207 rbcL sequences and multigene analyses (rbcL, psaA, psbA, cox1, and LSU) using 47 taxa from the order. The combined data set fully supports the monophyly of the Grateloupia sensu lato clade. Phylogenetic assessment of the reproductive structures in the order using the type of auxiliary cell ampullae, pericarp origin, and tetrasporangial development characters, supports a Grateloupia sensu lato clade distinct from the Halymeniaceae exemplified by the generitype Halymenia. As a result, we propose to reinstate the family Grateloupiaceae Schmitz based on the Grateloupia sensu lato clade and including Grateloupia and eight other genera: Dermocorynus, Mariaramirezia, Neorubra, Pachymeniopsis, Kintokiocolax, Phyllymenia, Prionitis, and Yonagunia. The emended Grateloupiaceae is distinguished from the Halymeniaceae by the following three characteristics; (i) simple unbranched and unilateral type of auxiliary cell ampullae, (ii) pericarp formed densely by the fusion of secondary medullary filaments from subcortical cells and lateral ampullary filaments from a fusion cell complex, (iii) tetrasporangia originating laterally from the outer cortex. The Halymeniales comprises the monophyletic Grateloupiaceae, Halymeniaceae sensu lato (which requires further study), and the Tsengiaceae.

Surface coating approaches for silicon (Si) have demonstrated potential for use as anodes in lithium-ion batteries (LIBs) to address the large volume change and low conductivity of Si. However, the practical application of these approaches remains a challenge because they do not effectively accommodate the pulverization of Si during cycling or require complex processes. Herein, Si-embedded titanium oxynitride (Si-TiON) was proposed and successfully fabricated using a spray-drying process. TiON can be uniformly coated on the Si surface via self-assembly, which can enhance the Si utilization and electrode stability. This is because TiON exhibits high mechanical strength and electrical conductivity, allowing it to act as a rigid and electrically conductive matrix. As a result, the Si-TiON electrodes delivered an initial reversible capacity of 1663 mA h g−1 with remarkably enhanced capacity retention and rate performance.

This paper presents switch fault detection and compensation control schemes for a modified dc-dc converter that relocates a diode location. The proposed fault detection and compensation control schemes are applicable to various energy generation systems that include energy storage. A fault detection index has been introduced to detect an open switch fault in the modified converter structure, and a compensation control method based on a mixed switching strategy has been developed. The fault-tolerant control method along with the detection scheme can make a system return to work even under a switch fault. The proposed schemes have been tested and verified both by the simulations and by experiments using a TMS320F28335 DSP. The results will significantly improve the reliability of alternative energy generation systems against open switch faults.

Fiber-shaped dye-sensitized solar cells (FDSSCs) with flexibility, weavablity, and wearability have attracted intense scientific interest and development in recent years due to their low cost, simple fabrication, and environmentally friendly operation. Since the Grätzel group used the organic radical 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) as the redox system in dye-sensitized solar cells (DSSCs) in 2008, TEMPO has been utilized as an electrolyte to further improve power conversion efficiency (PCE) of solar cells. Hence, the TEMPO with high catalyst oxidant characteristics was developed as a hybrid solid-state electrolyte having high conductivity and stability structure by being integrated with a lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) film for FDSSCs. The optimized 4-Oxo TEMPO (OX) based solid-state FDSSC (SS-FDSSC) showed the PCE of up to 6%, which was improved by 34.2% compared to that of the reference device with 4.47%. The OX-enhanced SS-FDSSCs reduced a series resistance (Rs) resulting in effective electron extraction with improved short-circuit current density (JSC), while increasing a shunt resistance (Rsh) to prevent the recombination of photo-excited electrons. The result is an improvement in a fill factor (FF) and consequently a higher value for the PCE.

Research on the magnetic levitation driving system of Hyperloop which has emerged as the next new vehicle is being carried out. Recently, magnetic levitation driving systems use EMS (Electro-Magnetic Suspension) and EDS (Electro-Dynamic Suspension) methods, and both EMS and EDS methods use two or more systems for propulsion/levitation/guidance. However, using two or more driving systems cause complexity of structure of whole system and increase significantly maintenance costs. Therefore, to solve these problems, this study proposed the concept and structure of Double-Sided Linear Induction Motor (DSLIM) that can be generating propulsion/levitation/guidance in one system, and carried out basic design and performance analysis by analyzing the design requirements of DSLIM. In addition, a detailed design through the selection of design parameters and analysis of characteristics that significantly affect the output characteristics was carried out to derive a performance improvement model for DSLIM.

Unlike the conventional railway traction motor, the concept of the dual-rotor in a dual-rotor permanent magnet synchronous motor (DR-PMSM) is that two rotors are mounted on the same rotation axis, and the outer rotor and the inner rotor rotate at different speeds. The DR-PMSM can transmit the power to the wheels in a structure that can cope with various problems of the reducer systems using mechanical gear mechanisms. In this research, the design study of the inner rotor including the permanent magnet is carried out in the application of the DR-PMSM. In designing the DR-PMSM models, surface permanent magnet (SPM) type and interior permanent magnet (IPM) type are considered according to the permanent magnet type of rotor, and IPM type is designed by dividing into bar type and V type. A comparative analysis of the three 1kW-class DR-PMSM models, in terms of electromagnetic properties, is performed to assess their general performance. The overall electromagnetic properties of the three designed models are similarly derived. But, the cogging torque and the rated torque characteristics of the IPM (V) type model are the best in comparison with the other models. In addition, the 1kW-class DR-PMSM prototype with V type magnet is fabricated to verify the validity of the analytical model and performance verification is performed.

Conventional diesel railway vehicles produce many air pollutants. In order to solve this problem, railway vehicles using eco-friendly hydrogen fuel cells are emerging. The main difference from the conventional traction motor is that it does not control the phase back electromotive force (phase-BEMF) separately at the maximum speed. Because of this, it should reduce the use of permanent magnets yet increase their size due to necessary high current. This paper performs the interior permanent magnet synchronous motor (IPMSM) design to meet the harsh electrical and mechanical constraints. Although the basic design is carried out to satisfy the design constraints, structural problems occur. These are resolved through the optimization process to attain the optimal design of a 314kW-class IPMSM for railway vehicles using hydrogen fuel cells.

This paper reports the design of a magnetic-geared permanent magnet synchronous motor (MG-PMSM) for a 45 kW tram traction system based on high torque density. In the case of the existing tram driving system, due to mechanical reduction gear and induction motor, it causes power transmission loss, low efficiency, and difficulty in lightweight. To solve this problem, research on the MG-PMSM, which combines a contactless magnetic gear with a high-power-density PMSM, is being actively conducted. This motor has a double rotor structure, and the inner rotor, including permanent magnet, and the outer rotor composed of pole-pieces rotate at different mechanical speeds. However, it is hard to design a tram driving system with a high torque density within limited conditions, because only one rotor in MG-PMSM is used as an output. In addition, there is no study conducted from basic design to final design, including gear ratio and topology selection in MG-PMSM for tram. Therefore, this paper presents the design process of MG-PMSM with high torque density to be applied to the 45 kW–class tram driving system. After designing the magnetic gear part that increases torque and efficiency by selecting an appropriate topologies-and-gear ratio that meets the constraints, the final finite elements method (FEM) model and electromagnetic field analysis results were derived by considering the number of poles and the number of slots. Through this, we confirmed that it is superior in output characteristics compared to the existing induction motor + mechanical gear.

In this paper, to complement the capability of the existing heating system using an electric-heating wire for melting snow and ice in railway turnouts, 250kHz-200W-class Induction Heating (IH) system was designed. The IH system consists of the resonant inverter and the IH device. In order to perform the electric circuit, the electromagnetic field, and the thermal analysis, the Multi-Physics analysis for IH system was derived. In addition, IH system was compared with the existing heating system.

Fiber-shaped solar cells (FSCs) with flexibility, wearability, and wearability have emerged as a topic of intensive interest and development in recent years. Although the development of this material is still in its early stages, bacteriophage-metallic nanostructures, which exhibit prominent localized surface plasmon resonance (LSPR) properties, are one such material that has been utilized to further improve the power conversion efficiency (PCE) of solar cells. This study confirmed that fiber-shaped dye-sensitized solar cells (FDSSCs) enhanced by silver nanoparticles-embedded M13 bacteriophage (Ag@M13) can be developed as solar cell devices with better PCE than the solar cells without them. The PCE of FDSSCs was improved by adding the Ag@M13 into an iodine species (I−/I3−) based electrolyte, which is used for redox couple reactions. The optimized Ag@M13 enhanced FDSSC showed a PCE of up to 5.80%, which was improved by 16.7% compared to that of the reference device with 4.97%.

Next-generation renewable energy sources and perovskite solar cells have revolutionised photovoltaics research and the photovoltaic industry. However, the presence of toxic lead in perovskite solar cells hampers their commercialisation. Lead-free tin-based perovskite solar cells are a potential alternative solution to this problem; however, numerous technological issues must be addressed before the efficiency and stability of tin-based perovskite solar cells can match those of lead-based perovskite solar cells. This report summarizes the development of lead-free tin-based perovskite solar cells from their conception to the most recent improvements. Further, the methods by which the issue of the oxidation of tin perovskites has been resolved, thereby enhancing the device performance and stability, are discussed in chronological order. In addition, the potential of lead-free tin-based perovskite solar cells in energy storage systems, that is, when they are integrated with batteries, is examined. Finally, we propose a research direction for tin-based perovskite solar cells in the context of battery applications.

The magnetic geared permanent magnet synchronous motor (MG-PMSM) is a PMSM that has two rotors with different rotation speeds and includes the function of magnetic gear. The design studies of the 45kW-class MG-PMSM are conducted for the application of the driving system for a tram. In this research, first, to derive the detailed model of the 45kW-class MG-PMSM for the tram, the analysis of the characteristics according to the stator winding method was performed. After selecting the winding method that can reduce the size of the MG-PMSM, two design topologies were applied to determine the number of stator poles, the number of outer rotor pole pieces, and the number of inner rotor poles of the MG-PMSM. A 45kW-class MG-PMSM detailed model was derived by applying a design topology that can minimize the size of the MG-PMSM, and it was confirmed that the required performance is satisfied through electromagnetic characteristics analysis. In addition, the 4.5kW-class small-scaled MG-PMSM prototype with concentrated winding was manufactured to verify the validity of the analytical model, and performance verification was performed.

Dyskinesia hyperpyrexia syndrome is a rare medical emergency in Parkinson’s disease. It is characterized by continuous dyskinesia associated with hyperthermia, rhabdomyolysis, and alteration of the mental state. We present the case of a 74-year-old woman who presented with recurrent dyskinesia hyperpyrexia syndrome. Although some provocation factors and clinical manifestations seem to be shared with parkinsonism hyperpyrexia syndrome, a clear distinction in management should be considered.

Background: Overweight contributes to type 2 diabetes mellitus (T2DM) development. Although the obesity paradox has been suggested in many vascular diseases, little information is available about stroke patients with T2DM. We investigated whether body mass index (BMI) has a differential impact on the incidence of major adverse cardiovascular events (MACE) in patients with ischemic stroke and T2DM.Methods: This retrospective study used a prospective cohort of patients with acute ischemic stroke and included consecutive patients with T2DM after excluding those with active cancer or who died within 1 month of an index stroke. We investigated the long-term risk of MACE (stroke, myocardial infarction, unstable angina, coronary revascularization procedure, and death) according to BMI.Results: Among the 1,338 patients, MACE occurred in 415 patients (31.1%) during a median follow-up of 3.6 years. Compared to the normal weight group, MACE occurred more frequently in the underweight group [adjusted hazard ratio (HR) 1.55, 95% confidence interval (CI): 1.01–2.38], but less frequently in the overweight group (adjusted HR: 0.87, 95% CI: 0.70–1.08) and obese group (adjusted HR: 0.58, 95% CI: 0.41–0.86) group. In analyses of association between BMI and each component of MACE, stroke and cardiovascular mortality indicated an L- and a U-shaped pattern, respectively. However, fatal or non-fatal stroke showed an inverse pattern, and fatal or non-fatal cardiovascular events showed a reversed J-shaped pattern.Discussions: This study showed the overall presence of the obesity paradox in stroke patients with T2DM. However, obese patients had different risks of cardiovascular events and stroke.

This paper presents a method of utilizing a non-contact position sensor for the tilting and movement control of a rotor in a rotary magnetic levitation motor system. This system has been studied with the aim of having a relatively simple and highly clean alternative application compared to the spin coater used in the photoresist coating process in the semiconductor wafer process. To eliminate system wear and dust problems, a shaft-and-bearing-free magnetic levitation motor system was designed and a minimal non-contact position sensor was placed. An algorithm capable of preventing derailment and precise movement control by applying only control without additional mechanical devices to this magnetic levitation system was proposed. The proposed algorithm was verified through simulations and experiments, and the validity of the algorithm was verified by deriving a precision control result suitable for the movement control command in units of 0.1 mm at 50 rpm rotation drive.

Abstract We found specimens of foliose Bangiales from the subtidal zone of Udo, Jeju Island, Korea. In molecular analyses of rbcL sequences, these Korean specimens were almost identical to Miuraea migitae from Osaka, Japan. In the morphological comparison, Korean specimens were consistent with habitat, color, and vegetative characteristics with the description of M. migitae. This is the first record of M. migitae outside the type locality and Nagasaki in Japan. This study confirms that new or unrecorded species of the order Bangiales may be discovered from subtidal habitats.

The genus Callophyllis is recorded as six separate species with imprecise species delimitation in Korea. To elucidate the species boundaries of Korean Callophyllis, we performed morphological observations and molecular analyses, and included three Japanese Callophyllis species from the type locality. From the results of molecular analyses using plastid rbcL and mitochondrial COI-5P genes, we confirmed ten Callophyllis species, including five cryptic ones: C. adhaerens, C. adnata, C. crispata, and C. japonica from Korea and Japan; C. hayamensis as an unrecorded species from Korea; C. cartilaginea, C. mollitia, C. repens, C. serratifolia, and C. undulata as new species from Korea. There were no Korean specimens that matched C. adnata or C. crispata from Japan, except Korean C. japonica, which formed a genetic group with the Japanese species. We obtained the interspecific divergences among the five cryptic species as 0.6–4.5% in rbcL and 2.8–8.4% in COI-5P. We recognized that the species diversity of Callophyllis has been underestimated from the northwestern Pacific region. The species boundary of Callophyllis from Korea and Japan will be a cornerstone to revealing the phylogenetic affinity of the genus distributed in both hemispheres of the western Pacific.

Poly(D,L-lactic acid) (PDLLA) and poly(ethylene glycol) (PEG) was used to modify mechanical and biodegradability properties of poly(L-lactic acid) (PLLA) through solution blending method using solvent mixture of dichloromethane-ethanol. Polymer samples were then characterized using FTIR, DSC, UTM, and enzymatic degradation test. FTIR spectrum of pure PLLA showed specific IR absorption peaks at wavenumber of 3504 cm-1 (-OH), 1757 cm-1 (-C=O), and 1381 cm-1 (-CH3 symmetric). Further, polymer blend samples showed absorption peak shifts at 1755 cm-1 and 1382 cm-1 for PLLA/PDLLA due to stereocomplex interaction and at 3429 cm-1 due to hydrogen bond interaction. DSC results showed that there was melting temperature depression for all polymer blend samples compared to pure PLLA with increasing of either PDLLA or PEG composition. In PLLA/PDLLA, two melting points were discovered because of homocrystallite and stereocomplex phase formation. While PLLA/PEG samples showed increasing crystallinity to 69% at 20%-wt PEG composition. Mechanical analysis showed that 10%-wt of PDLLA addition in PLLA produced better mechanical performance than pure PLLA while 20%-wt of PEG addition showed highest elongation at break with the value of 89%. Polymer blend samples were degradable during enzymatic degradation test represented by percent weight loss with maximum value of 21% for PLLA/PEG sample. Keywords: polymer properties, solution-blending, Poly(lactic acid), polymer blend, enzymatic degradation

Specimens of Umbraulva with greenish iridescent were collected in the subtidal zone of Jeju Island, Korea. To investigate these collections, plastid rbcL and tufA sequencing of six greenish iridescent specimens, including four Umbraulva japonica, were analyzed. Phylogenetic analysis of a concatenated multigene alignment found that the greenish iridescent specimens belonged to a yet undescribed taxon in the genus Umbraulva. We herein propose the name Um. yunseulla sp. nov. for this specimens. Juveniles of Um. yunseulla sp. nov. resemble the generitype Um. japonica in appearance, showing globular to subglobular and funnel-shaped habits, but the blades of this new species are not split longitudinally like those of Um. japonica. Although the multigene phylogenetic tree showed the polyphyletic clade of Umbraulva with respect to the genus Ryuguphycus, Um. yunseulla sp. nov. formed a clade with Um. japonica and Um. amamiensis by weak bootstrap support. These findings, Um. yunseulla sp. nov., highlight the importance of studying the biodiversity of subtidal habitats from Jeju Island, Korea and further emphasize the need for investigations of macroalgae in the mesophotic zone around the Korean peninsula. [ABSTRACT FROM AUTHOR]

Several species classified to the genus Ulva are primarily responsible for causing green tides all over the world. For almost two decades, green tides have been resulted in numerous ecological problems along the eastern coast of Jeju Island, Korea. In order to characterize the species of Ulva responsible for causing the massive blooms on Jeju Island, we conducted DNA barcoding of tufA and rbcL sequences on 183 specimens of Ulva from eight sites on Jeju Island. The concatenated analysis identified five bloom-forming species: U. australis, U. lactuca, U. laetevirens, U. ohnoi and a novel species, U. pseudo-ohnoi sp. nov. Among them, U. australis, U. lactuca, and U. laetevirens caused to the blooms coming mainly from the substratum. U. ohnoi and U. pseudo-ohnoi sp. nov. were causative the free-floating blooms. Four species, except U. australis, are characterized by marginal teeth. A novel species, U. pseudo-ohnoi sp. nov., is clearly diverged from the U. lactuca, U. laetevirens, and U. ohnoi clade in the concatenated maximum likelihood analysis. Accurate species delimitation will contribute to a management of massive Ulva blooms based on this more comprehensive knowledge. [ABSTRACT FROM AUTHOR]

This paper is a study on the application position of skew in order to reduce the cogging torque of a magnetic geared synchronous motor (MGM). The cogging torque affects the noise and vibration of the motor, so it should be reduced as much as possible. To solve this problem, a conventional permanent magnet (PM) synchronous motor is skewed to a PM. However, unlike other synchronous motors, the MGM has pole pieces (PPs), and a larger cogging torque is generated due to a larger reluctance difference. There have been few studies on the reduction of cogging torque of MGM, so it is essential to study the skew structure of MGM. Therefore, this paper has derived the optimum skew method by comparing and analyzing three models of MGM skewed to PM, PP, and PM and PP simultaneously. [ABSTRACT FROM AUTHOR]

This paper discusses the effect of nanocrystalline cellulose (NCC) when used as filler on polylactic acid (PLA)-based nanocomposites and on its mechanical properties and permeability. NCC was produced from commercial cellulose and another cellulose source, i.e. oil palm empty fruit bunch, by hydrolysis of microcrystalline cellulose with sulphuric acid and by oxidation with ammonium persulfate. The nanocomposites were made by adding nanocrystalline cellulose with varying compositions into PLA. A solvent casting method was used to produce a nanocomposite film with 5% v/v triacetin as a coupling agent. Both methods produced crystalline celluloses within the micro and nano range with mean particle size at 99.5 nm and 157.9 nm for the sulphuric acid hydrolysis and the ammonium persulfate oxidation method, respectively. The utilization of NCC as PLA composite filler increased the percentage of elongation at break with a highest percentage 19.02% for addition of 1% NCC filler. However, higher compositions of cellulosic filler resulted in a decreasing trend of tensile strength and elongation at break. Higher content of NCC filler in the PLA matrix increased the nanocomposite's water vapor permeability. [ABSTRACT FROM AUTHOR]

This paper proposes an optimal control algorithm through lateral displacement and yaw angle in curved road of shallow-depth subway systems. In the case of the surface transportation, which has recently been introduced, curved driving performance is required for the downtown. The existing research works are the main research theme of the lateral displacement restoration control, but there is a limit to smooth operation when the curve is run only by receiving the lateral information. However, when the yaw angle displacement information is obtained, it is possible to consider the turning angle of the vehicle while the vehicle is driving in a curved road. However, it is difficult to control because the change of yaw angle is more sensitive than lateral drift. Therefore, this paper suggests an algorithm that uses yaw angle displacement control. The validity and usefulness of the proposed control algorithm is verified by experimental results using a small-scale bogie system. [ABSTRACT FROM AUTHOR]

This paper proposes an algorithm to obtain better results in the integrated control by reflecting the characteristics of the individual control of the front wheel and the rear wheel of tram systems. In the case of the surface transportation, which has recently been introduced, severely curved driving performance is required for the downtown. It is possible to decrease the curve radius and to improve the performance of the straight driving with the individual torque control. Therefore, the individual torque control performance of the motor is the most important point of the surface transportation. The front and rear wheels have different torque characteristics, and the length of the bogie during curve travel also affects these results. This system is more controllable than the system with 1Controller 4Motor (1C4M) in the form of 2C4M with the front and rear wheels being individually controlled, allowing more precise control because of its higher degree of freedom. Because of this individually controlled characteristic, it is possible to control more precisely in the integrated control considering the characteristics of the front wheel and the characteristics of the rear wheel. The validity of the proposed control algorithm is verified by experimental results using a small-scale bogie system. [ABSTRACT FROM AUTHOR]

The concept of sustainable leadership is increasingly gaining popularity among organizational scholars. However, empirical evidences for the effectiveness of sustainable leadership are still lacking. This study investigated whether and how diverse elements of sustainable leadership influence the effectiveness of organization. Analyzing the large data collected from the employees of diverse U.S. federal agencies, this study found that sustainable leadership practices explained a significant variance of diverse aspects of organizational effectiveness. However, the different elements of sustainable leadership influenced the different aspects of organizational effectiveness to a different degree. The results showed that the relative strengths of the effects of each element of sustainable leadership differed across different aspects of organizational effectiveness. For example, promoting work/life balance was the most significant predictors of employee satisfaction, while its effect diminished when investigated against other aspects of organizational effectiveness. [ABSTRACT FROM AUTHOR]

The red algal genus Amalthea was first described from New Zealand with one species, A. freemaniae. We discovered a new species of Amalthea from Korea, Amalthea rubida sp. nov., and described it based on morphology and rbcL sequences. A. rubida is characterized by a foliose, membranous and soft thallus having loosely arranged anticlinal medullary filaments, much like A. freemaniae, except for a difference of the cortex thickness in the basal part of vegetative structure. In the rbcL phylogenetic analyses, A. rubida formed a clade with A. freemaniae from New Zealand and Halymenia abyssicola from Mexico. A. rubida showed 5.7% interspecific divergence to A. freemaniae and 4.7% to H. abyssicola. Our discovery of A. rubida expands the distribution of Amalthea from the oceanic southwestern Pacific into the continental northwestern. A targeted global study is needed to fully reveal the species diversity and phylogenetic relationships of the genus Amalthea and members of the order Halymeniales. [ABSTRACT FROM AUTHOR]

This study concerns the improvement and enhancement of the properties of poly(L-lactic acid) (PLLA) through simple solution blending of pure PLLA with different kinds of biodegradable polymers. Synthesized PLLA was blended with synthesized poly(D,L-lactic acid) (PDLLA) or poly(ethylene glycol) (PEG) at various composition ratios in a solvent mixture of dichloromethane/ethanol at room temperature to produce dipolymer. The polymer-blend properties were analyzed using FTIR, DSC, UTM data and an enzymatic degradation test was conducted. It was found that PLLA blend films were obtained with limitation of the second polymer content up to 20% (w) through solvent casting. From the DSC data, two different melting temperature peaks showed that stereocomplex formation occurred during polymer precipitation for all PLLA/PDLLA blends, while only one single melting temperature peak appeared in the PLLA/PEG blend. Regarding the mechanical properties, the PLLA/PEG blend showed better performance with an improvement of the mechanical strength by around 11.18% and an improvement of the elongation at break by around 89% compared to pure PLLA. Furthermore, after the 48-hour enzymatic biodegradability test, the PLLA/PEG blends showed improvement of biodegradability with 21.88% of sample weight-loss compared to 2.53% for pure PLLA. [ABSTRACT FROM AUTHOR]

Production of biodegradable polylactic acid (PLA) from biomass-based lactic acid is widely studied for substituting petro-based plastics or polymers. This study investigated PLA production from commercial lactic acid in a batch reactor by applying a direct melt polycondensation method with two kinds of catalyst, γ-aluminium(III) oxide (γ-Al2O3) or zinc oxide (ZnO), in reduced pressure. The molecular weight of the synthesized PLA was determined by capillary viscometry and its structural properties were analyzed by functional group analysis using FT-IR. The yields of polymer production with respect to the theoretical conversion were 47% for γ-Al2O3 and 35% for ZnO. However, the PLA from ZnO had a higher molecular weight (150,600 g/mol) than that from γ-Al2O3 (81,400 g/mol). The IR spectra of the synthesized PLA from both catalysts using polycondensation show the same behavior of absorption peaks at wave numbers from 4,500 cm-1 to 500 cm-1, whereas the PLA produced by two other polymerization methods -- polycondensation and ring opening polymerization -- showed a significant difference in % transmittance intensity pattern as well as peak area absorption at a wave number of 3,500 cm-1 as --OH vibration peak and at 1,750 cm-1 as -C=O carbonyl vibrational peak. [ABSTRACT FROM AUTHOR]