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In this study, we successfully fabricated vertically aligned Zn 2 SnO 4 (ZTO)-Fe 3 O 4 core-shell microsphere (MS)-based thermal interface material (TIM) formed by an external magnetic field. The thermal conductivity of the randomly distributed ZTO-Fe 3 O 4 core-shell/PDMS-based TIMs was enhanced with increasing loading fraction of fillers and TIM with 25 vol % fillers 2.5 times effectively reduced GPU temperature compared to bare PDMS sample. Moreover, the vertically-aligned 25 vol% ZTO-Fe 3 O 4 core-shell filler embedded TIM additionally reduced temperature by 5.1 % and 24.1 % compared to randomly dispersed ZTO-Fe 3 O 4 MS TIMs and bare PDMS, respectively. Experimental results showed that the ZTO-Fe 3 O 4 TIMs can be used as high thermal conductivity TIM filler, and vertically aligned core-shell filler can maximize thermal conductivity by forming an effective thermal path from bottom to top. The theoretical analysis results obtained using COMSOL Multiphysics 5.6 simulation corresponded well with experimental ones. Our suggested vertically aligned ZTO-Fe 3 O 4 core-shell-based TIM can provide an effective heat dissipation path for advanced semiconductor devices with a wide range of applications. [ABSTRACT FROM AUTHOR]

Abstract Economic growth and urbanization have reduced urban land resources to the point that such resources are now, in some cases severely, limited. In order to support sustainable development and to solve the problem of land shortages in urban areas, one practical solution is the shifting of land usage from above the surface to underground. However, in most countries, including Korea, the cadastral system cannot adequately handle the legal, administrative, and technical aspects of the registration and maintenance of underground parcels. The main purpose of this research, therefore, was to propose a conceptual registration framework for 3D underground parcels. In order to do that, issues of unregistered underground space were summarized, and the legal, administrative, and technical limitations were revealed. In consideration of these limitations, the registration framework for 3D underground parcels is herein proposed. This framework consists of four steps: 1) preparation of 3D underground parcel data with consideration for information regarding 3D underground cadastral surveying and building-components; 2) definition of 3D underground parcels, based on deep underground regulation in Korea and the registration extent, registration unit, absolute height and relative height of systems; 3) 3D underground cadastral registration according to the three types of cadastral maps and land registration; 4) registration of 3D underground rights, such as ownership and sectional superficies of the 3D underground parcel. Finally, in order to implement the proposed registration framework for a 3D underground parcel, legal, administrative, and technical improvements are proposed. Highlights • The exiting cadastral system cannot fully support land administration related to 3D underground space in most countries. • A registration framework for 3D underground parcel is required to efficiently manage underground properties in urban area. • The proposed registration framework for the 3D underground parcel establishes the workflow of the 3D underground cadastral system. [ABSTRACT FROM AUTHOR]

Abstract Since aluminum responds to various oxidizers and has a high energy density, there are high expectations for its usefulness as a fuel. However, it is covered with an aluminum oxide film, which has a high melting point, and thus, its ignition is difficult. One method suggested to solve this problem is nickel coating; however, in contrast to the extensive amount of research conducted on the overall phenomenon of aluminum combustion, research regarding Ni-coated aluminum is still in nascent stages. This study was carried out to further elucidate the ignition mechanism; thus, millimeter-sized (∼2.38 mm) aluminum particles were used to observe the surface where ignition occurs in air. The spatial and temporal resolutions were heightened by prolonging the heating period. The aluminum particles were nickel coated using electro/electroless methods, and surface analysis by SEM, thermal analysis by TGA/DSC, and species analysis by XRD and EDS were carried out. In addition, two-wavelength pyrometry was used to measure the ignition temperature. The results show that regardless of the nickel content in the coating of the aluminum particles, the ignition temperature was approximately 2400 K, similar to the melting point of aluminum oxide. The thermodynamic and thermophysical characteristics of nickel, aluminum, aluminum oxide, and nickel (II) oxide, and the surface/cross-sectional analysis, thermal and species analysis, and high-speed cinematography of the quenched samples provided a detailed explanation of the ignition process. Through this ignition mechanism, the emitted spectrum of AlO (as an intermediate combustion material) was traced to explain the decrease in ignition delay with increase in nickel content. [ABSTRACT FROM AUTHOR]

• Modified OpenFOAM accurately predicts large-scale 2-phase flow, conjugate heat transfer & boiling in CE-PECS using temp-dependent properties. The PECS (Passive Ex-vessel corium retaining and Cooling System) is installed inside the EU (European Union)-APR (Advanced Power Reactor) 1400 to prevent CCI (corium-concrete interaction) and to cool down the corium under an ex-vessel severe accident. The main phenomenon in the PECS is the natural convection of the cooling water generated by the heat from the corium. A verification experiment on the cooling capability of the PECS has been conducted in the CE (Cooling Experiment)-PECS. A benchmark CFD analysis of the CE-PECS (Cooling Experiment-PECS) was performed using the modified OpenFOAM solver. In this study, the physical properties such as specific heat, dynamic viscosity, and density of water were modified to provide inputs as a function of temperature. Since the modified solver was developed to analyze PECS, the mesh was made as simple as and the number of cells is also optimized to reduce the computational load. As a result of a simulation using the improved solver, the prediction of both the mass flow rate and the temperature change of the cooling water showed good accuracy compared to the case of inputting the existing constant properties. [ABSTRACT FROM AUTHOR]

Power gating circuit suffers from large amount of rush current during wakeup, especially when all switch cells are turned on simultaneously. If each switch cell is turned on at a different time, rush current can be reduced. It is shown in this paper that rush current can be reduced even more if signal transition time (or signal slew) to each switch cell is adjusted. We define wakeup scheduling as to determine turn-on time and signal slew of each switch cell; the goal is to minimize wakeup delay while keeping rush current below the maximum value that is allowed. The determined turn-on time and signal slew are implemented using a buffered tree. The wakeup scheduling and buffered tree construction are integrated into a design flow. To adapt to process variation, we use adjustable delay buffers in the wakeup network. We also apply grid-based design flow and use Schmitt triggers to implement large designs. Experiments in an industrial 1.1 V, 32-nm technology demonstrate that the wakeup delay is reduced by 12% on average of example circuits compared with turn-on scheduling. [ABSTRACT FROM AUTHOR]

Complex of platelet-derived growth factor (PDGF) isoforms and PDGF receptors have important functions in the regulation of growth and survival of various cell types. Herein, it was found that aberrant PDGFC expression is closely associated with survival rates in triple-negative breast cancer (TNBC) patients. In addition, PDGFC expression was identified to be significantly increased in TNBC cells unlike other subtypes such as PDGFA, PDGFB, and PDGFD. Apparently, the effects of specific PDGF receptor (PDGFR) inhibitors such as sunitinib and ponatinib on HCC1806 and Hs578T TNBC cells were investigated. Both inhibitors decreased cell viability in a dose-dependent manner. In addition, the inhibitors completely inhibited cell growth in both the cell lines and decreased the expression of matrix metalloproteinase-1 (MMP-1), one of the metastasis-related genes. Cell migration was also decreased by the inhibitors. Finally, the combined effects of the inhibitors with doxorubicin (DOX) were investigated. The results showed that the combination of two PDGFR inhibitors with DOX inhibited the growth of cells and enhanced the apoptotic cell death more uniformly than DOX. Consequently, it is demonstrated that PDGFR inhibitors, sunitinib and ponatinib hold the potential for effective treatment of TNBC. [ABSTRACT FROM AUTHOR]

• Simulating IR signatures and flow structure of plume at the rear of solid rocket motor. • Using HTPB (weak afterburning) and NEPE (strong afterburning) propellants. • Confirming the effect of altitude, flight Mach number, and motor size. In this study, radiation signatures of rocket plumes based on HTPB and NEPE propellants are simulated under varying altitudes, flight Mach numbers, and motor size. The flow field of plume is calculated by computational fluid dynamics, and the infrared signature is predicted using a Ludwig model. To verify the numerical method, experiments were conducted using small rocket motors and radiometric FTIR. The acceptable agreement between numerical calculation and the experiment was obtained in 2 – 5 μm wavelength region. The total radiance decreases with increasing altitude whether afterburning exists or not. A decreasing rate in the radiance of the plume with strong afterburning is larger than that of the plume with weak afterburning. The change in total intensity according to altitude depends on the afterburning and is directly affected by the radiating area. As the flight Mach number increases, total radiance, total intensity, and radiating area decrease. The motor size makes radiation intensity increase exponentially; exponent value is from 2.6 to 2.7. As the motor size increases, the effect of altitude increases, while the effect of flight Mach number decreases. [ABSTRACT FROM AUTHOR]

Cation substitution technique in halide perovskites (HPs) is one of the famous schemes to enhance the characteristics of HPs-based electronic and optoelectronic devices. Here, we fabricated rubidium (Rb) substituted inorganic double halide perovskites (HPs) Cs 2−x Rb x AgBiBr 6 (x = 0, 0.05, 0.1, 0.2, and 0.3) film-based resistive switching (RS) devices and investigated effects of Rb cation substitution on characteristics of RS devices. Grain sizes of the formed Cs 2−x Rb x AgBiBr 6 films gradually increased as increase of Rb contents in the precursor. All of the fabricated RS devices demonstrated non-volatile bipolar RS behavior, device with the Rb content x = 0.1 showed a particularly high on/off ratio (9.29 × 102) of about 30 times greater than pristine Cs 2 AgBiBr 6 -based ones (3.09 × 10). In addition, it has been shown that an appropriate amount of Rb substitution at the level of x = 0.1 can effectively prevent the appearance of other crystalline phases at high humidity condition of > 80 %. Through various analytical techniques including SEM, XPS, and SCLC measurement, it was confirmed that an enlargement in grain size resulting in a decrease in defects such as Br vacancies in the fabricated film can lead to an increase in resistance at a high resistance state (HRS) and high on/off resistance ratio. This study provides a facile and feasible way to enhance performances of HPs-based RS devices for practical electronic memory applications. [Display omitted] • We fabricated rubidium (Rb) substituted inorganic double halide perovskites (HPs) Cs 2−x Rb x AgBiBr 6 film-based resistive switching (RS) devices • Grain sizes of Cs 2−x Rb x AgBiBr 6 (x = 0, 0.05, 0.1, 0.2, and 0.3) films gradually increased as increase of Rb contents. • Cs 2−x Rb x AgBiBr 6 -based RS devices with x = 0.1 showed a particularly high on/off ratio (9.29 × 102) of about 30 times greater than pristine one. • An appropriate amount of Rb substitution at the level of x = 0.1 can prevent the appearance of other phases at high humidity condition of > 80 %. [ABSTRACT FROM AUTHOR]

The evolution of multi-dimensional grains of solid rocket motor propellant was carried out using the partial interface tracking method. This method applies the Lagrangian approach to the axisymmetric area of the X – Y plane and the fin area of the Y – Z plane to analyze the multi-dimensional grain burnback. The Lagrangian approach is an effective way to simulate the axisymmetric or 2D shape of a grain, but it is difficult to determine the 3D shape using this method. Therefore, the partial interface tracking method was designed to solve this problem and to get solutions quickly. The grid data resulting from this method is generated in a standard file format, which makes it easy to check the grid shape through commercial modeling software. This method showed good agreement with previous literature and was effective for numerous different grains. Also, it was confirmed that the code can be applicable to the 0D flow field model. [ABSTRACT FROM AUTHOR]

• A full-scale WWTP treating PRW was monitored to evaluate pollutant removal. • Removal efficiencies of SCOD and benzene in influent were achieved more than 70%. • Sulfuritalea and Azoarcus were mainly responsible for degradation of benzene. • Ottowia and Thauera were possibly involved in phenol degradation as well. This research investigated the process efficiency and microbial communities and their diversity in a full-scale wastewater treatment plant (WWTP) fed with petroleum refining wastewater (PRW) that contained toxic hydrocarbon contaminants and carcinogens. Process parameters and bacterial community structures were monitored for six months to create a link between microbial dynamics and influent characteristics of petrochemical wastewater. The WWTP showed a stable process with efficiencies >70% for both soluble chemical oxygen demand (SCOD) and benzene removal. More than 30 genera were identified by metagenomic analysis, and the bacterial populations changed significantly during the operation period. Among them, genera Sulfuritalea (11.9 ± 3.5%) , Ottowia (4.3 ± 2.2%) , Thauera (3.1 ± 7.2%) and Hyphomicrobium (1.3 ± 0.7%) were dominant and important bacterial genera that may have been responsible for the degradation of aromatic compounds such as benzene and phenol. [ABSTRACT FROM AUTHOR]

Aberrant interleukin-1 beta (IL-1β) expression is associated with cancer development, metastasis, and poor prognosis. Here, we have investigated the regulatory mechanism of IL-1β expression, and the inhibitory effect of zerumbone (ZER) on IL-1β expression and IL-1β-induced signatures, including cell invasion and signaling activation in triple negative breast cancer (TNBC) cells. The basal IL-1β and cell invasiveness levels were significantly higher in TNBC cells, compared with non-TNBC cells. The invasiveness of TNBC cells was also increased following IL-1β treatment. In contrast, the invasiveness of TNBC cells was decreased following IL-1 receptor antagonist (IL-1RA) treatment. Additionally, the basal IL-1β level and the invasiveness of TNBC cells were decreased by Bay11-7085. In contrast, overexpression of NF-κB (p65) caused an increase in IL-1β expression in TNBC cells. Our results showed that treatment with ZER decreased the basal IL-1β expression level, and the phosphorylation level of NF-κB, in TNBC cells. Furthermore, we found that ZER completely suppressed IL-1β-induced NF-κB phosphorylation, but did not suppress IL-1β-induced Akt phosphorylation, in TNBC cells. Our results also demonstrate that IL-1β-induced cell invasion is suppressed by ZER in TNBC cells. Taken together, we demonstrated that IL-1β expression is regulated by the NF-κB-dependent pathway, and that elevated IL-1β is directly influencing the invasiveness of TNBC cells. ZER down-regulates IL-1β expression through the inhibition of NF-κB activity, and then suppresses cell invasiveness of TNBC. [ABSTRACT FROM AUTHOR]