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Abstract To enhance our understanding of the carbon cycle in the Arctic Ocean, comprehensive observational data are crucial, including measurements from the underlying ice water. This study proposed a practical method for calibrating pCO2 sensor using measured dissolved inorganic carbon and total alkalinity. Our findings suggested the minimum number of bottle samples needed for calibration to ensure 1% accuracy. Additionally, we identified the significant role of a decrease in dissolved inorganic carbon due to photosynthesis and the increase in buffer capacity of the seawater from the release of excess alkalinity by sea ice in regulating pCO2. The mean air–sea CO2 fluxes were −48.9 ± 44.6, −7.3 ± 14.6, and −1.4 ± 2.8 mmol m−2 d−1 in the southern Chukchi Sea, northern Chukchi Sea, and northern East Siberian Sea, respectively. We found a robust negative correlation between the flux and sea ice concentration in the Arctic Sea ice regions.

Strain engineering provides an attractive approach to enhance device performance by modulating the intrinsic electrical properties of materials. This is especially applicable to 2D materials, which exhibit high sensitivity to mechanical stress. However, conventional methods, such as using polymer substrates, to apply strain have limitations in that the strain is temporary and global. Here, we introduce a novel approach to induce permanent localized strain by fabricating a stressor on SiO2/Si substrates using fiber laser irradiation, thereby enabling precise control of the surface topography. MoS2 is transferred onto this stressor, which results in the application of ~0.8% tensile strain. To assess the impact of the internal strain on the operation of ReRAM devices, the flat-MoS2-based and the strained-MoS2-based devices are compared. Both devices demonstrate forming-free, bipolar, and non-volatile switching characteristics. The strained devices exhibit a 30% reduction in the operating voltage, which can be attributed to bandgap narrowing and enhanced carrier mobility. Furthermore, the strained devices exhibit nearly a two-fold improvement in endurance, presumably because of the enhanced stability from lattice release effect. These results emphasize the potential of strain engineering for advancing the performance and durability of next-generation memory devices.

The rapid evolution of microelectronics and display technologies has driven the demand for advanced manufacturing techniques capable of precise, high-speed microchip transfer. As devices shrink in size and increase in complexity, scalable and contactless methods for microscale placement are essential. Laser-induced forward transfer (LIFT) has emerged as a transformative solution, offering the precision and adaptability required for next-generation applications such as micro-light-emitting diodes (μ-LEDs). This study optimizes the LIFT process for the precise transfer of silicon microchips designed to mimic μ-LEDs. Critical parameters, including laser energy density, laser pulse width, and dynamic release layer (DRL) thickness are systematically adjusted to ensure controlled blister formation, a key factor for successful material transfer. The DRL, a polyimide-based photoreactive layer, undergoes photothermal decomposition under 355 nm laser irradiation, creating localized pressure that propels microchips onto the receiver substrate in a contactless manner. Using advanced techniques such as three-dimensional profilometry, X-ray photoelectron spectroscopy, and ultrafast imaging, this study evaluates the rupture dynamics of the DRL and the velocity of microchips during transfer. Optimization of the DRL thickness to 1 µm and a transfer velocity of 20 m s⁻1 achieves a transfer yield of up to 97%, showcasing LIFT’s potential in μ-LED manufacturing and semiconductor production.

In recent years, researchers have increasingly focused on alloy design in additive manufacturing (AM) to adjust the microstructure and improve the mechanical properties. The microstructure of columnar grains, strong texture, and chemical inhomogeneity in designed alloy exhibit anisotropic properties, which negatively affect the mechanical properties of the materials. One such material affected by this problem is titanium (Ti), which is known for its exceptional mechanical properties. Unlike other alloys, titanium lacks grain refiners that can ameliorate the columnar structure. Consequently, numerous studies are currently underway to refine the Ti grain through the addition of solute elements. In this study, Ti6Al4V with Cu element was deposited using the directed energy deposition (DED) process to investigate the feasibility of Ti6Al4V-xCu and analyze the effect of Cu addition. Ti6Al4V with Cu addition was successfully deposited and exhibited evenly distributed composition. In addition, finer grains were more created than the deposited Ti6Al4V by converting columnar to equiaxed grain due to the high cooling rate facilitated by high restriction factor Q of Cu. The deposited Ti6Al4V–4Cu of mechanical properties exhibited a 19 % increase in ultimate tensile strength, a 19 % increase in hardness at the top, and reduced elongation compared to the deposited Ti6Al4V, owing to the precipitation of Ti2Cu, grain refinement, and solid solution of Cu. However, although the hardness of the deposited Ti6Al4V–7Cu exhibited a 36 % increase in hardness at the top, Ti2Cu precipitate was generated significantly, which adversely exhibited a 26 % decrease in ultimate tensile strength compared to the deposited Ti6Al4V.

In recent decades, the cooling water discharge (CWD) from thermoelectric power plants into coastal waters has increased. The higher temperatures at the discharge outlets can elevate the seawater partial pressure of carbon dioxide (pCO2), potentially resulting in increased carbon dioxide (CO2) emissions or reduced CO2 absorption. Using a comprehensive global power plant database, we evaluated the impact of CWD on surface water CO2. Our assessment suggests that CWD from coastal power plants has the potential to contribute to a decline in oceanic CO2 uptake by 0.09–0.69 Tg C yr−1 (equivalent to 0.3–2.5 Tg CO2 yr−1). This estimation considered solely the influence of air–sea CO2 exchange, excluding the impact of air–sea heat exchange following cooling water discharge. Therefore, our estimate of 0.09–0.69 Tg C yr−1 is likely an upper theoretical limit. While our estimate appears minor in relation to global estimates of the oceanic CO2 flux, this impact of CWD should be addressed on a national scale. For precise quantification of the impact of CWD on local air–sea CO2 flux, accurate information on environmental factors such as wind speeds, mixed layer depth, and background carbonate chemistry is essential.

Offloading virtual reality (VR) computations to a cloud computing entity can enable support for VR services on low-end user devices but may result in increased latency, which will lead to mismatch between the user’s viewport and the received VR image, thus inducing motion sickness. Predicting future motion and rendering future images accordingly is a promising solution to the latency problem. In this paper, we develop velocity- and error-aware model switching schemes applicable to a wide range of existing motion prediction models. First, we consider the chattering problem of machine learning (ML)-based prediction models and the relationship between the velocity and the prediction error gap between an ML model and the case of no prediction (NOP). Accordingly, we propose a velocity-aware switching (VAS) scheme that combines the outputs from the ML model and the NOP case via a weight determined by the head motion velocity. Next, we develop an ensemble method combining a set of outputs from VAS and other models, called error-aware switching (EAS). EAS switches between model outputs based on the error statistics of those outputs under the parallel execution of multiple models, including VAS models. For EAS, schemes for both hard switching and soft integration of the model outputs are proposed. We evaluate the proposed schemes based on real VR motion traces for diverse ML-based prediction models.

An organic nano‐floating‐gate transistor (ONFGT) with both photosynaptic and electrical memory functions is developed using a perovskite (CsPbBr3) NC‐insulating polymer (polystyrene; PS) nanocomposite and CsPbBr3 NCs as the tunneling and floating gate layers, respectively. The introduction of the CsPbBr3 NCs–PS nanocomposite layer improves the photoresponsivity of the ONFGT under ultraviolet–visible irradiation, resulting in an increase in both the photocurrent and the light‐to‐dark current ratio by 10−8 A and 104 orders of magnitude, respectively. It also exhibits high responsivity (0.804 A W−1) and external quantum efficiency (249.3%) under 400 nm irradiation. Furthermore, the photosynaptic characteristics of the ONFGT under visible‐light irradiation are investigated. To mimic biological nervous systems, the photocurrent of the device is dynamically modulated by varying the light intensity and duration. Notably, an increase in synaptic weight is observed under repeated photonic stimulations, as shown by changes in synaptic weight with each light pulse. Also, the ONFGT exhibits excellent nonvolatile memory characteristics in the dark, displaying a hysteresis window value of 2.9 V for a gate double sweep under ±5.0 V. Consequently, the perovskite NCs–insulating polymer nanocomposite tunneling layer is crucial for enabling photoresponsivity and memory characteristics in nano‐floating‐gate transistors, making them suitable for multifunctional electronic devices.

The genetic investigation of the archeological or museum samples, including endangered species, provides vital information necessary to plan, implement, and revisit conservation strategies. In South Korea, the Asian black bear went almost extinct in wild by 2002, without leaving any authentic specimens representing the native population. Recently researchers found a set of animal bones in a natural cave in Mt. Taebaek (South Korea), suspected to be of a bear. In the present study, we undertook a molecular investigation and radiocarbon dating to establish the species’ identity, phylogenetic position, and approximate age of the recovered specimen. The genetic investigation (CytB, COI, D-loop, SRY, and ZFX-ZFY) identified the sample as a male Asian black bear with close phylogenetic affinity with Northeast Asian bears. Radiocarbon dating estimated the bones to be aged 1800–1942 calAD. These findings indicate that the bone specimens found in the natural cave in Mt. Taebaek were from an individual that naturally inhabited South Korea long before the importing of farm bears (the 1980s) and initiation of wild population restoration (2004). The present study provides the first genetic information record of the native South Korean black bear. Our findings reaffirm the appropriateness of the ongoing bear restoration program in South Korea, with the reintroduction of individuals from North Korea and Russia.

The factors that control the partial pressure of carbon dioxide (pCO2) in the Pacific sector of the Southern Ocean were investigated in April 2018, onboard the icebreaker, ARAON. The mean (± 1σ) of the sea surface pCO2 was estimated to be 431 ± 6 μatm in the north of the Ross Sea (NRS), 403 ± 18 μatm in the Amundsen–Bellingshausen Sea (ABS), and 426 ± 16 μatm in the western Antarctic Peninsula and Weddell Sea (WAP/WS). The controlling factors for pCO2 in the NRS appeared to be meridionally different based on the southern boundary of the Antarctic Circumpolar Current (SB; ~62.5°S in the Ross Sea). The sea surface pCO2 exhibited a strong correlation with salinity and the difference between the O2/Ar (ΔO2/Ar) values of the sample and air-saturated water in the north and south of the SB, respectively. The pCO2 in the ABS and western WAP/WS displayed a strong correlation with salinity. Furthermore, ΔO2/Ar and sea ice formation appear to be the dominant factors that control pCO2 in the Confluence Zone (CZ) and northern parts of WAP/WS. The estimated air–sea CO2 fluxes (positive and negative values indicate the source and sink for atmospheric CO2, respectively) range from 3.1 to 18.8 mmol m−2 d−1 in the NRS, −12.7 to 17.3 mmol m−2 d−1 in the ABS, and −59.4 to 140.8 mmol m−2 d−1 in the WAP/WS. In addition, biology-driven large variations in the air–sea CO2 flux were observed in the CZ. Our results are the most recent observation data acquired in austral autumn in the Southern Ocean.

Towards further integration and miniaturization of e-textiles, in this work, authors demonstrate an integrated electronic fibre platform by fabricating multiple electronic components such as transistors, inverters, ring oscillators, and thermocouples onto the outer surface of a microfibre substrate.

This study investigates the influence of the Southern Annular Mode (SAM) on chlorophyll- a (Chl- a ) concentrations and the underlying mechanisms governing their associated environmental variations in the mid-latitude (35–50° S) ocean from 1998 to 2021. The intensification of westerly winds during positive SAM phases influences meridional water transport and mixed layer depth (MLD), which are both critical factors that affect surface nutrient availability. A marked contrast in the relationship between the meridional current anomaly and the SAM was observed, with reduced northward transport of nutrient-rich water in regions north of 50° S during positive SAM phases. This reduction could be attributed to the poleward migration of the westerly winds, which impeded the meridional current from reaching the mid-latitudes. The relationship between SAM and MLD south of 50° S was positive whereas that in the mid-latitude eastern (60–110° E) South Indian Ocean and eastern (90–140° W) South Pacific Ocean was negative or weak. The immediate effect of a more positive SAM on Chl- a in the mid-latitude ocean was reduced productivity caused by enhanced nutrient depletion. However, in the mid-latitude eastern South Pacific Ocean, the northward migration of the zonal mean meridional current anomaly closely aligned with the lagged correlation pattern between SAM variability and Chl- a over time, suggesting that the delayed northward transport of nutrient-rich waters may partially counterbalance the immediate effects of the SAM on ocean productivity. This mechanism was not present in the mid-latitude eastern South Indian Ocean, implying that future climate change may variably affect these regions. Our findings emphasize the importance of considering regional differences and temporal lags when evaluating the influence of SAM variability on ocean productivity and nutrient dynamics in the context of climate change.

Implementing a heterostructure by vertically stacking two-dimensional semiconductors is necessary for responding to various requirements in the future of semiconductor technology. However, the chemical-vapor deposition method, which is an existing two-dimensional (2D) material-processing method, inevitably causes heat damage to surrounding materials essential for functionality because of its high synthesis temperature. Therefore, the heterojunction of a 2D material that directly synthesized MoS2 on graphene using a laser-based photothermal reaction at room temperature was studied. The key to the photothermal-reaction mechanism is the difference in the photothermal absorption coefficients of the materials. The device in which graphene and MoS2 were vertically stacked using a laser-based photothermal reaction demonstrated its potential application as a photodetector that responds to light and its stability against cycling. The laser-based photothermal-reaction method for 2D materials will be further applied to various fields, such as transparent display electrodes, photodetectors, and solar cells, in the future.

Offloading heavy virtual reality (VR) computational operations to a network edge computation entity is receiving increasing attention as a tool to wirelessly and energy efficiently provide low-end client devices with high-quality and immersive interactive VR services anytime and anywhere across the globe. In this work, we aim to provide an understanding of various characteristics of VR computation offloading through comprehensive experiments conducted using a prototype testbed for edge-assisted VR processing and streaming. First, we investigate the benefits of VR offloading in terms of computational load and power consumption reduction for a client device compared to standalone operation. Next, we measure VR traffic patterns, including frame size and data and packet rates with various settings, such as different resolution and encoding options. We also measure several performance metrics associated with the quality of experience, namely, frame rate, packet loss rate, and image quality, with various configuration settings. Then, we present latency measurement studies and investigate per-component latency with various settings. Furthermore, we report the rigorous experiments performed to study the impacts of latency and motion patterns on the black borders formed due to image reprojection and the overfilling technique used to eliminate these black borders.

Photophysical and photochemical features of graphene quantum dots (GQDs) strongly depend on their chemical nature that remains challenging to be controlled in a systematic and uniform manner. Here the authors report an efficient solvent-catalyst-aided growth of chemically tailored N-doped GQDs.

Background and Objectives: The goal in treating anterior cruciate ligament (ACL) injury especially in revision cases is return to sports activity by regaining dynamic postural stability. Among various methods to achieve this goal, additional anterolateral ligament reconstruction (ALLR) is gaining attention. The purpose of this study was to evaluate the effects of additional ALLR in revision ACL reconstruction (RACLR). Materials and Methods: Patients who underwent RACLR between July 2015 and June 2018 were enrolled. The exclusion criteria were less than 1-year follow-up, age older than 45 years, concomitant multiple ligament injuries, contralateral knee injury, subtotal or total meniscectomized state, and articular cartilage lesions worse than Outerbridge grade 3. Thirty-nine patients (20 patients; RACLR only (Group A), 19 patients; RACLR with additional ALLR (Group B)) were included. Clinical scores (Lysholm score, subjective International Knee Documentation Committee (IKDC) score, Tegner activity scale), isokinetic strength test, single-leg-hop for distance test (SLHDT), Y-balance test (YBT) were checked preoperatively and 1-year postoperatively. Results: Limb symmetry index values in YBT showed significantly better result in Group B 1-year postoperatively (Group A: 97.2 ± 4.0, Group B: 100.3 ± 2.9, p = 0.010), although there were no differences preoperatively between groups (Group A: 90.4 ± 6.7, Group B: 89.3 ± 5.5, p = 0.594). Regarding clinical scores, isokinetic strength tests, and SLHDT, there were no differences between groups preoperatively nor 1-year postoperatively. Conclusions: Additional ALLR in RACLR helped patients gain better dynamic postural stability at 1-year postoperative follow-up.

Abstract The tung tree produces large seeds with approximately 40–50% of their composition consisting of non-edible oil. α-Eleostearic acid makes up about 80% of tung oil, while linoleic acid and oleic acid make up 7 and 6%, respectively. The oil is readily oxidized due to the three, conjugated double bonds in α-eleostearic acid; however, it is stable inside the tung seed, which is expected to contain strong antioxidative compounds that protect the oil from oxidation. Previously, we isolated and identified a catechol-type lignan (3,3′-bisdemethylpinoresinol) and neolignans (isoamericanol A and americanol A) from the seeds of tung tree fruits that exhibited strong antioxidative activity, similar to that of Trolox. In this study, we show that the catechol-type lignan and neolignans are specifically present in the seed coat of the tung tree fruit seeds. The lignans were not detected in any other tissue, such as the pericarp, bark, leaves, or wood of the tree. The lignan content was determined in each developmental stage of the fruit, and the amount of the three lignans in the tung seeds was the highest in the green mature stage. This was likely because the amount of tung oil was also at its highest during this stage, and the oil composition was stable. Our results indicate that the catechol-type lignan and neolignans are located within the seed coat of the tung tree fruit seeds, where they protect the oil in the endosperm from autoxidation and polymerization processes.

Molecular electronics holds promise for device miniaturization yet can only be realized by choosing specially designed molecular species to date. Here, Shin et al. show tunable rectifying characteristics in a molecular heterojunction with non-functionalized molecules and two-dimensional semiconductors.

The role of sea ice melting on the air-sea CO2 flux was investigated at two ice camps in the East Siberian Sea of the Arctic Ocean. On average, sea ice samples from the two ice camps had a total alkalinity (TA) of ∼108 and ∼31 μmol kg–1 and a corresponding salinity of 1.39 and 0.36, respectively. A portion (18–23% as an average) of these sea ice TA values was estimated to exist in the sea ice with zero salinity, which indicates the excess TA was likely attributed to chemical (CaCO3 formation and dissolution) and biological processes in the sea ice. The dilution by sea ice melting could increase the oceanic CO2 uptake to 11–12 mmol m–2 d–1 over the next 21 days if the mixed layer depth and sea ice thickness were assumed to be 18.5 and 1.5 m, respectively. This role can be further enhanced by adding TA (including excess TA) from sea ice melting, but a simultaneous release of dissolved inorganic carbon (DIC) counteracts the effect of TA supply. In our study region, the additional impact of sea ice melting with close to unity TA:DIC ratio on air-sea CO2 exchange was not significant.

This study examines interannual variations in the seawater CO2 partial pressure (pCO2) for months (August–October) with frequent tropical cyclone (TC) events in the northwestern subtropical Pacific Ocean (22°N–28°N, 135°E–145°E) between 2007 and 2017. The temperature-normalized pCO2 averaged over August–October showed a year-to-year variation ranging from 346 to 359 μatm over the 11 study years, which appeared to be related to the variation in vertical mixing that likely results from the TC activity in these months. Sea surface temperature and wind data consistently supported the association between mixing and TC intensity. Nonetheless, the pCO2 reduction caused by negative sea-surface temperature anomalies found over the TC season (July–October) shifted the study area from a CO2 source to a CO2 sink over these months. In the south (17°N–22°N) of the study area, mixing-driven variations in pCO2 were smaller during the same months, which appeared to be caused by the relatively deeper mixed layer depth and the more homogenous profile of CO2 in this tropical region. These results suggest that more extensive pCO2 measurements are required to fully resolve the effect of TCs on the carbonate system from the regional- to the basin-scale in the western Pacific Ocean, where TC intensity is expected to increase in the future.

Movable object type wave power generators produce energy through the process of primary energy conversion, which converts the potential and kinetic energy of the waves into mechanical energy, secondary energy conversion that converts it into energy for generator operation using a mechanical system or hydraulic system, and final energy conversion, the last step in power generation. The secondary energy conversion system that transmits and amplifies energy according to the primary energy conversion needs to secure durability while power generation performance varies greatly depending on how the secondary energy conversion system is built. As a result, reliability assessment of systems based on system engineering are a very important issue. Therefore, in this study, for the conceptual design based on reliability assessment of the secondary energy conversion system, the system concept was established using the integrated computer-aided manufacturing (ICAM) definition for function modeling (IDEF0), a system analysis method, while necessary equipment and process flow diagrams (PFD) were derived. In addition, the database (DB) and formula of the secondary energy conversion system were constructed, and reliability assessment algorithms and programs were developed. Finally, the PFD and reliability assessment program were verified by applying them to a representative movable object type wave power generator.

The aim of this study was to investigate the plasma dopamine and serum serotonin levels in humans with and without caffeine (CAFF) ingestion during treadmill running exercise. Thirty male volunteers participated in the randomized experiment involving two groups: CON (n = 15, 200 mL of tap water) versus CAFF (n = 15, 3 mg/kg CAFF and 200 mL tap water). After treadmill running, the dopamine level was significantly increased in the CAFF group (P < 0.01) and was significantly higher than in the CON group (P < 0.01). Serotonin was significantly increased in both groups after treadmill running (P < 0.05). However, serotonin levels showed no significant statistical difference between the groups. Prolactin and cortisol were significantly increased in both groups after treadmill running (P < 0.01). However, there was no significant statistical difference between groups. β-endorphin level was significantly increased in the CAFF group at after treadmill running (P < 0.01) and was significantly higher than in CON after treadmill running (P < 0.01). In conclusion, 3 mg/kg CAFF ingestion before treadmill running stimulated dopamine release without inhibiting serotonin, which may reduce central fatigue.

With the tightening of environmental regulations (i.e., IMO Tier III), natural gas (NG) has been spotlighted as an eco-friendly fuel with few air pollutants other than nitrogen oxides (NOx) and sulfur oxides (SOx). For reasons of economic efficiency, it is mainly stored and transported in a liquid state at -163 °C, which is a cryogenic temperature, using a liquefied gas storage tank. Accordingly, it is necessary to reduce the boil-off gas (BOG) occurrence due to the heat flow according to the temperature difference between the inside and outside of the storage tank. Therefore, in this study, a BOG measurement test on an independent-type storage tank made up of SUS304L was carried out. The test results showed the tendency for BOG occurrence according to the temperature under different filling ratios.

Abstract Low voltage operational organic transistors (

This study determines the presence of R. tanezumi from in Nepal using morphological and molecular analyses. Morphologically, it is indistinguishable with R. rattus owing to similar fur colour and morphometric data. However, molecular identification and phylogenetic analysis using sequences of the mitochondrial DNA (mtDNA) Cytochrome B (CytB) gene revealed two different species R. rattus and R. tanezumi from collected specimens. The genetic distance between R. rattus and R. tanezumi was found 0.043. In phylogenetic tree, the clade of R. tanezumi is distinguished into two sub-clades, R. tanezumi found in Nepal, and East Asian countries, China, Laos, Thailand, Viet Nam, and South Korea have genetic distance 0.031, suggesting the different lineages of R. tanezumi. This study confirmed the R. tanezumi present in Nepal. Our findings suggest that morphological analysis and molecular study should be carried out simultaneously for accurate identification of small sized cryptic mammals like R. tanezumi and R. rattus.

Fiber electronics is a key research area for realizing wearable microelectronic devices. Significant progress has been made in recent years in developing the geometry and composition of electronic fibers. In this review, we present that recent progress in the architecture and electrical properties of electronic fibers, including their fabrication methods. We intensively investigate the structural designs of fiber-shaped devices: coaxial, twisted, three-dimensional layer-by-layer, and woven structures. In addition, we introduce remarkable applications of fiber-shaped devices for energy harvesting/storage, sensing, and light-emitting devices. Electronic fibers offer high potential for use in next-generation electronics, such as electronic textiles and smart integrated textile systems, which require excellent deformability and high operational reliability.

Background: Relatively few studies on the peripheral sweating mechanisms of trained tennis athletes have been conducted. The purpose of this study was to compare the sweating capacities of tennis athletes against untrained subjects (controls). Methods: Thirty-five healthy male volunteers participated including 15 untrained subjects and 20 trained tennis athletes (nationally ranked). Active heat generation was performed for 30 min (running at 60%VO2max) in a climate chamber (temperature, 25.0°C ± 0.5°C; relative humidity, 60% ± 3%, termed active heating). Sweating data (local sweat onset time, local sweat volume, activated sweat glands, sweat output per gland, whole body sweat loss volume) were measured by the capacitance hygrometer-ventilated capsule method and starch-iodide paper. Mean body temperature was calculated from tympanic and skin temperatures. Results: Local sweat onset time was shorter for tennis athletes (p

In order to understand the feeding ecology and dietary differences of roe deer (Capreolus pygargus tianschanicus) in different seasons and altitudes, this study was carried out at three altitudinal sites (Songdang 250–270 m above sea level (ASL), Aradong 330–370 m ASL, Mt. Hallasan 1100 m ASL) on Jeju Island, South Korea. Altogether, 205 plants taxa of six categories of foods (forbs-climbers, graminoids, trees, shrubs, conifers, and ferns) were identified using morphological and molecular analyses. The highest number of dietary plants was found in summer (93 taxa) and at Aradong (124 taxa) and lowest at Songdang (71 taxa) and in winter (51 taxa). Food categories were significantly different among the seasons (F = 15.646, p

In order to utilize wave energy, various wave power systems are being actively researched and developed and interest in them is increasing. To maximize the operational efficiency, it is very important to monitor and maintain the fault of components of the system. In recent years, interest in the management cost, high reliability and facility utilization of such systems has increased. In this regard, fault diagnosis technology including fault factor analysis and fault reproduction is drawing attention as an important main technology. Therefore, in this study, to reproduce and monitor the faults of a wave power system, firstly, the failure mode of the system was analyzed using FMEA analysis. Secondly, according to the derived failure mode and effect, the thrust bearing was selected as a target for fault reproduction and a test equipment bench was constructed. Finally, with the vibration data obtained by conducting the tests, the vibration spectrum was analyzed to extract the features of the data for each operating status; the data was classified by applying the three machine learning algorithms: naïve Bayes (NB), k-nearest neighbor (k-NN), and multi-layer perceptron (MLP). The criteria for determining the fault were derived. It is estimated that a more efficient fault diagnosis is possible by using the standard and fault monitoring method of this study.

When developing an automobile control application, its scheduling parameters as well as the control algorithm itself should be carefully optimized to achieve the best control performance from given computing resources. Moreover, since the wide acceptance of the AUTOSAR standard, where finer-granular scheduling entities (called runnables) rather than the traditional real-time tasks are used, the number of scheduling parameters to be optimized is far greater than the traditional task-based control systems. Hence, due to the vast problem space, it is not feasible to reuse existing time-consuming search-based optimization methods. With this motivation, this paper presents an analytical codesign method for deciding runnable periods that minimize given control cost functions. Our solution approach, based on the Lagrange multiplier method, can find optimized runnable periods in polynomial times due to its analytical nature. Moreover, our evaluation results for synthesized applications with varying complexities show that our method performs significantly better (12% to 59% of control cost reductions) than a state-of-the-art evolutionary algorithm. To the best of our knowledge, this study is one of the first attempts to find runnable periods that maximize a given system’s control performance.

In 2012, the International Maritime Organization (IMO) regulated the emissions of SOx and NOx by setting the emission control area and strengthened the regulations on ship building and operation. Because the environmental regulations have been reinforced, there has been a drastic increase in LNG-fueled ships. Therefore, it is necessary to carry out systematic research on the design of the LNG fuel tank, which is one of the important components of LNG fuel supply systems. In this study, aiming to design a type-B LNG fuel tank used in the real structure, a procedure for structural integrity assessment considering the International Gas Carrier (IGC) Code was proposed. A 10,000 TEU containership was chosen as an operating vessel, and independent type-B tank was selected as an LNG fuel tank. Structural integrity was evaluated by applying a systematic procedure based on the IGC Code. A series of finite element analysis was conducted under the various design loads and operating conditions. Fatigue life and fatigue damage were calculated using the numerical results obtained from transient thermal-structural analysis and fatigue analysis to provide the safety level of the design scheme.

The primary objective of this study was to investigate the molecular compositions of humic-like substances (HULISs) in size-resolved ambient aerosols, which were collected using an Anderson-type air sampler (eight size cuts between 0.43 and 11 μm) during the winter season (i.e., the heating period of 8−12 January 2018) in Songdo, South Korea. The aerosol samples collected during the pre- (preheating, 27 November−1 December 2017) and post-winter (postheating, 12−16 March 2018) periods were used as controls for the winter season samples. According to the concentrations of the chromophoric organics determined at an ultraviolet (UV) wavelength of 305 nm, most of the HULIS compounds were found to be predominantly enriched in particles less than 2.1 μm regardless of the sampling period, which shows that particulate matter (diameter less than 2.5 μm; PM2.5) aerosols were the dominant carriers of airborne organics. Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (UHR FT−ICR MS) analysis of the aerosol-carried organic substances revealed that as the aerosol size increased the proportions of CHO and nitrogen-containing CHO (CHON) compounds decreased, while the proportion of sulfur-containing CHO (CHOS) species increased. In particular, the ambient aerosols during the heating period seemed to present more CHO and CHON and less CHOS molecules compared to aerosols collected during the pre- and postheating periods. The aerosols collected during the heating period also exhibited more aromatic nitrogen-containing compounds, which may have originated from primary combustion processes. Overall, the particle size distribution was likely influenced by source origins; smaller particles are likely from local sources, such as traffic and industries, and larger particles (i.e., aged particles) are likely derived from long-range transport generating secondary organic aerosols (SOAs) in the atmosphere. The results of the size-segregated particles can be utilized to understand particle formation mechanisms and shed light on their toxicity to human health.