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The characteristics of thermomechanical fatigue life of complex electronic device system, micro-scaled design, is highly sensitive to changes in design factors. The solder ball, which acts as a linkage between the circuit board and the package, is a vital part to examine the performance of electronic device system. Repeated thermal loading causes the solder crack growth in models, eventually leads to the breakdown of devices. There have been lots of studies on investigating the fatigue life of solder joints employing well-established finite element procedure. However, generating a finite element model reflecting the whole device often requires unnecessarily large finite element matrices which may increase the computational cost and solder joint fatigue life can be highly dependent on the mesh resolutions. Recent studies suggest the sub-modeling method to handle the meshing process and alleviate the computational cost. In this paper, we delineate the methodology of two-step sub-modeling framework, aimed at improving the mesh fidelity of complex models while ensuring the efficiency of labor-intensive process of solder joint fatigue analysis. We employ the strain energy-based Darveaux's fatigue model to predict the fatigue life of solder joints. Through the investigation of the predicted fatigue life of solder joints across various sets of design parameters, it has been observed that the design factors of electronic devices exhibit a clear pattern in relation to the predicted fatigue life, even when only the second step of two-step sub-modeling framework is considered. Our findings suggest that it is efficient to utilize solely the second step of two-step sub-modeling framework to identify an appropriate reduced design space, where design parameters can be strategically selected for designing an optimal model. • Two-step sub-modeling enables efficient fatigue life prediction of DRAM modules compared to the conventional approach. • An efficient framework allows the geometric effect of solder ball to be quickly verified. • The proposed method aids in identifying appropriate design space guidelines to optimize subsequent model development. [ABSTRACT FROM AUTHOR]

The Jigunsan Formation is the middle Ordovician shale-dominated transgressive succession in the Taebaeksan Basin, located in the eastern margin of the North China platform. The total organic carbon (TOC) content and some geochemical properties of the succession exhibit a stratigraphically distinct distribution pattern. The pattern was closely associated with the redox conditions related to decomposition, bulk sedimentation rate (dilution), and productivity. To explain the distinct distribution pattern, this study attempted to construct a high-resolution sequence stratigraphic framework for the Jigunsan Formation. The shale-dominated Jigunsan Formation comprises a lower layer of dark gray shale, deposited during transgression, and an upper layer of greenish gray siltstone, deposited during highstand and falling stage systems tracts. The concept of a back-stepped carbonate platform is adopted to distinguish early and late transgressive systems tracts (early and late TST) in this study, whereas the highstand systems tracts and falling stage systems tracts can be divided by changes in stacking patterns from aggradation to progradation. The late TST would be initiated on a rapidly back-stepping surface of sediments and, just above the surface, exhibits a high peak in TOC content, followed by a gradually upward decrease. This trend of TOC distribution in the late TST continues to the maximum flooding surface (MFS). The perplexing TOC distribution pattern within the late TST most likely resulted from both a gradual reduction in productivity during the late TST and a gradual increase in dilution effect near the MFS interval. The reduced production of organic matter primarily incurred decreasing TOC content toward the MFS when the productivity was mainly governed by benthic biota because planktonic organisms were not widespread in the Ordovician. Results of this study will help improve the understanding of the source rock distribution in mixed carbonate–siliciclastic successions within a stratigraphic framework, particularly for unconventional shale reservoirs. [ABSTRACT FROM AUTHOR]

Abstract: Korean species of the genus Frontina (Diptera: Tachinidae) are reviewed. This Palaearctic genus currently includes five nominal species, of which three occur in Korea (Frontina femorata, F. laeta and F. tricolor). We found that the only Korean record of this genus was F. laeta, but examination of the voucher specimens revealed that they actually were F. femorata. We provide a key, descriptions and illustrations of the three Korean species. [Copyright &y& Elsevier]

Abstract: This report describes the initial discovery of the genus Pseudogonia of the tribe Goniini (Diptera: Tachinidae) in Korea. This Old World genus currently includes seven nominal species. In the process of revising Korean Goniini, we were able to collect Korean representatives of the type species (P. rufifrons), and hereby provide the descriptions and illustrations of both sexes. [Copyright &y& Elsevier]

Abstract: The properties of a new cathode material of nano-sized TiO2-coated Ni powder for application in molten carbonate fuel cells (MCFCs) are investigated. The material is prepared by a sol–gel method. X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM) with energy dispersive X-ray analysis (EDAX), transmission electron microscopy (TEM) and Raman spectroscopy are employed to characterize the cathode material. The nano-sized TiO2 particles are homogenously coated on the surface of the Ni powder. A stable LiTi1−x Ni x O2 phase is formed on the surface of the Ni powder during immersion in molten carbonate at 650°C. The solubility of the TiO2-coated Ni cathode is about 50% lower compare with that of a pure Ni cathode. [Copyright &y& Elsevier]

• 3D grid-based screening process could be used to quickly screen different sub-basins or aquifers for CO 2 storage potential. • Instead of estimating the storage capacity, Gravitational Number is used as screening criterion. • The proposed criteria and ranking framework are applicable to identify suitable regions for the early CCS implementation. • The ranking results of six sub-basins in the Gunsan Basin indicate that the East Sub-basin is the most promising region. This study presents an approach to screen sedimentary basins for their CO 2 geological storage potential based on a 3D grid with geological data. The 3D grid-based screening was applied to the Gunsan Basin, offshore Korea, for selecting potential sub-basins. Six sub-basins were recognized and prioritized using a set of quantifiable criteria, reflecting storage capacity, geological risk, and socio-economic aspects. Nine criteria were defined and weighed to reflect local priority and geological characteristics. Every grid cell was populated with geological and geometrical properties, scored and ranked for each criterion. Typically, the storage capacity is used for evaluating the storage potential of a basin, which, however, was not estimated here due to the low quantity of available data. Instead, the capacity potential was quantified by combining the pore volume and Gravitational Number for each grid cell. Mean score values for each sub-basin indicate that the East Sub-basin is the most promising region, containing a suitable aquifer with an estimated storage capacity of a few hundreds of MtCO 2. Therefore, we suggest that the Gunsan Basin is suitable for implementing a CCS program with an injection rate of 4 MtCO 2 /year for 30 years. Moreover, we suggest that the 3D grid-based screening process could be used to quickly screen different sub-basins or potential aquifers by depth. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of hyperglycemia on the expression of the aquaporin (AQP) isoforms in the diabetic rat vagina. Methods: Female Sprague-Dawley rats (230-240 g, n = 45) were divided into control (n = 10) and experimental (n = 35) groups. Diabetes in the experimental group was induced by intraperitoneal injection of streptozotocin (STZ, 65 mg/kg). STZ-induced diabetic rats were left untreated or given subcutaneous injections of insulin (3 U/d). After 2 and 4 weeks, the blood glucose was measured, and the vaginal blood flow was assessed by Doppler flowmetry. The expression and cellular localization of AQP1 and AQP2 in the rat vagina were determined by Western blot and immunohistochemistry. Results: The vaginal blood flow (mL/min/100 g tissue) after pelvic nerve stimulation was significantly lower in the STZ-induced diabetic rats (21.9 ± 6.5 at 2 weeks and 21 ± 2.8 at 4 weeks) compared with the control group (55.5 ± 8.9 at 2 weeks and 52.9 ± 6.5 at 4 weeks; P < .05). In contrast, the vaginal blood flow response was significantly greater in the insulin-treated diabetic groups (47.7 ± 8.7 at 2 weeks and 47.7 ± 8.4 at 4 weeks) and comparable to that of the control group. The protein expression of AQP2 was significantly lower in the STZ-induced diabetic rats and was restored to the control level after insulin treatment. However, no change was seen in AQP1 expression. Thus, hyperglycemia might cause downregulation of AQP2 expression in the diabetic rat vagina. Conclusion: These results suggest that decreased vaginal lubrication in diabetic women might result from changes in aquaporin expression, in addition to a reduction in the vaginal blood flow response. [ABSTRACT FROM AUTHOR]

In this study, we made a novel alternative cathode material of molten carbonate fuel cell (MCFC) using electroless deposition of Co on the surface of the Ni powder. Using this manufacturing method, we expect that economical and large-scale cathode can be made easily. The cathode prepared by this method formed LiCo1−yNiyO2 phase in molten (Li0.62K0.38)2CO3 at 650 °C under CO2:O2=66.7:33.3% atmosphere, its solubility is 40% lower than that of NiO cathode. In the unit cell test, the performance of the cell composed of Co-coated Ni cathode was same as that of the cell composed of NiO cathode. Thus the cathode made by Co-coated Ni powder used as an alternative cathode can maintain the advantages of NiO cathode and lengthen the lifetime of MCFC. [Copyright &y& Elsevier]

The shale gas potential of a Late Devonian shale sequence in the Liard Basin, an important unconventional gas reservoir, was assessed using the retained gas volume based on gas generation potential and hydrocarbon expulsion efficiency. Evaluation of gas generation potential in the Liard Basin depends on understanding the characteristics of the original organic matter. However, due to high thermal maturity, it is difficult to estimate the characteristics of the original organic matter from conventional methods. The type of original organic matter was inferred from inorganic geochemical proxies that reflect productivity (Ex-SiO 2), terrestrial sediment input (Al 2 O 3 , Zr), and oxygen level in the bottom water (Mo EF and U EF). By considering the present day TOC (TOCpd) and the type of original organic matter, the original hydrogen index (HIo) and original total organic carbon (TOCo) values were calculated to range from 200 to 700 mgHC/gTOC and from 0.3 to 29.0 wt%, respectively. The measured TOCpd values were similar to the TOCpd calculated from the 1-D petroleum system model using the original organic matter characteristics inferred in this study, which indicates that the TOCo values are reliable. Based on the evolution of the TOCo during its thermal history, the total gas generation potential in the Late Devonian shale sequence (550 ft) of the Liard Basin is estimated to be 1690 bcf/section. Considering the total gas in place (496 bcf/section), based on the estimated ultimate recovery, approximately 70% of the hydrocarbon might have been expelled. The retained gas volume fluctuates vertically in the Late Devonian shale sequence. The retained gas volume is higher in the 3946–3993 m (136 bcf/section) and 3993–4047 m (281 bcf/section) intervals than other intervals (less than 60 bcf/section), indicating that these intervals are the most prospective for shale gas exploration and development in the studied well. • The Late Devonian shale sequence in the Liard Basin is important unconventional gas reservoir. • Gas generation potential was estimated from TOCo inferred from inorganic geochemical data. • Based on the estimated ultimate recovery, 30% of gas generation potential is retained. • The estimated retained gas volume shows vertical change though the Late Devonian shale sequence. [ABSTRACT FROM AUTHOR]

New proton exchange membranes were prepared and evaluated as polymer electrolytes for a proton exchange membrane fuel cell (PEMFC). Two types of fluorinated poly(arylene ether)s (FPAEs) were synthesized by nucleophilic aromatic substitution of decafluorobiphenyl (DFBP) with 4,4′-(hexafluoroisopropylidene)diphenol (HFDP) and bisphenol-A (BPA). The FPAEs so prepared were converted into proton exchange polymers by sulfonation with fuming sulfuric acid (30% SO3). The FPAEs and sulfonated-fluorinated poly(arylene ether)s (S-FPAEs) with various sulfonation levels were characterized using 1H NMR, thermogravimetric analysis (TGA) and back titration, and then successfully evaluated as proton exchange membranes (PEM) with unit cell operation. power output measurements of S-DFBP-HFDP carried out at a cell temperature of 80 °C. They exhibited a maximum power density of 425.5 mW/cm2 at 1150 mA/cm2. [Copyright &y& Elsevier]

The estimation of the hydrocarbon generation potential of shales in unconventional and conventional resources depends on an accurate estimation of the original total organic carbon (TOCo) content and original hydrogen index (HIo). TOCo is partially lost during thermal alteration whereas Mo/Al is hardly altered, suggesting that a linear correlation between them in immature shales can be used to estimate TOCo in mature shales. However, this correlation method is not applicable when immature and mature shales have different kerogen types. Herein, a refined method to calculate TOCo for mature shales using a linear correlation between two major fractions of organic matter (generative organic carbon (GOC), and non-generative organic carbon (NGOC)) and Mo/Al is proposed. If thermal maturity increases, only GOC that generates hydrocarbon is reduced without change in NGOC associated with kerogen type. However, the linear correlation between TOCo and Mo/Al of immature shales can change the NGOC as well as GOC in the mature shales. To estimate TOCo of mature shales, original GOC (GOCo) in the mature shale is calculated using linear correlation between the GOC and Mo/Al of the immature shale and subsequently, the calculated GOCo is combined with the NGOC unconverted from thermal alteration in the mature shales. We applied the refined method to the Devonian Muskwa Formation where mature and immature shales have different kerogen types. The HIo was calculated from the ratio of GOCo to TOCo using the refined method. The calculated HIo values are similar to those roughly deduced from the cross-plot of Tmax vs. HI values. The result indicates that the refined method is useful for accurate estimation of TOCo and GOCo in the shales. The refined method improves the estimation of original characteristics of organic matter in a shale gas reservoir where the original kerogen type cannot be identified due to an increase in thermal maturity. • TOCo is important factor evaluating hydrocarbon generation potential in source rock. • Ratio of TOCo to Mo/Al in immature shale can be used to estimate TOCo in mature shale. • The ratio can't be used to evaluate TOCo if both shales have different kerogen type. • We estimate reliable TOCo by using correlation between two fractions of TOC and Mo/Al. • The proposed method can be useful when kerogen type can't be identified. [ABSTRACT FROM AUTHOR]

Abstract: The dynamics of the melt-quenched amorphization in TiO x mixed Ge2Sb2Te5 films were studied using real-time reflectivity measurements with a nanosecond laser pulse and various amounts of TiO x . It was observed that the laser-power required for amorphization was significantly reduced by 27% when 9.1mol% of TiO x was incorporated with Ge2Sb2Te5. The lowering of the thermal conductivity of the films, due to the increase in the number of interface between the Ge2Sb2Te5 and TiO x phases, led to an increase in the thermal efficiency. Such enhanced thermal efficiency is of great technological importance in phase change storage applications. [Copyright &y& Elsevier]