Indirect Studies of Electroweakly Interacting Particles at 100 TeV Hadron Colliders

There are many extensions of the standard model that predict the existence of electroweakly interacting massive particles (EWIMPs), in particular in the context of the dark matter. In this paper, we provide a way for indirectly studying EWIMPs through the precise study of the pair production processes of charged leptons or that of a charged lepton and a neutrino at future 100 TeV collider experiments. It is revealed that this search method is suitable in particular for Higgsino, providing us the $5\sigma$ discovery reach of Higgsino in supersymmetric model with mass up to 850 GeV. We also discuss how accurately one can extract the mass, gauge charge, and spin of EWIMPs in our method.Comment: 20 pages, 7 figures, 5 table

Hemming for Joining High Strength Steel Sheets

AbstractA high strength steel sheet is used to make the hollow sections for the body structure of automobiles. The hollow sections, which are typically joined by resistance spot welding have insufficient energy absorption because the joins are not continuous. Thus, to overcome this problem, the hollow section is joined using the hemming process. The hemming of the high strength steel sheet was successfully performed using punch with stopper. The high strength steel hollow sections joined by hemming and resistance spot welding were then examined by tensile and fatigue tests. The hollow section with hemmed joins showed better performance in both tests. The overlapping joins of the hemmed hollow section have greater strength as compared to the resistance of spot welding joins

Isotopic fractionation of water during snow formation: Experimental evidence of kinetic effect

Deuterium excess(d-excess=δD-8・δ^(18)O), which is calculated using two water isotope ratios(δD and δ^(18)O), is an indicator of kinetic isotope fractionation. The d-excess value reflects the evaporation process from the ocean or ice-crystal growth. Consequently, d-excess records preserved in ice cores may provide a climatic history of ocean surface conditions at the vapor source area. J. Jouzel and L. Merlivat(J. Geophys. Res., 89, 11749, 1984) proposed an isotope model to analyze information from ice cores. That model includes kinetic fractionation during snow formation, depending on the degree of the supersaturation ratio of vapor. However, no experiment was conducted under the controlled supersaturation ratio. Experiments described herein measured the isotopic ratios of the vapor and artificial snow produced under a controlled supersaturation ratio to confirm the kinetic isotope effect experimentally. Results indicate a higher d-excess value for ice crystals at a higher vapor supersaturation ratio and provide experimental evidence for the kinetic effect during snow formation

Preoperative Computed Tomography-Derived Bone Densities in Hounsfield Units at Implant Sites Acquired Primary Stability

The purpose of this study was to evaluate preoperative CT-derived bone densities in Hounsfield units (HU) at implant sites that acquired primary stability, and to compare these values to the optimal bone densities proposed in the literature. Fifty-one patients, 18 males (37 implant sites) and 33 females (67 implant sites) between 2003 and 2010 were assessed. CT data for different jaw sections, regions, and operating procedures were compared using the Kruskal-Wallis test and Scheffe's test for multiple comparisons (P < 0.05). The mean bone density in the maxilla was significantly lower than that in the mandible (P < 0.05); the mean bone densities in the 4 jaw regions decreased in the following order: anterior mandible > anterior maxilla > posterior mandible > posterior maxilla. The bone densities assessed by HU fell into the range of optimal bone densities associated with acquired primary implant stability proposed in the literature

Performance Evaluation of Alternating Current Square Waveform Submerged Arc Welding as a Candidate for Fabrication of Thick Welds in 2.25Cr-1Mo Heat-Resistant Steel

The paper evaluates the performance of alternating current (AC) square waveform submerged arc welding (SAW) as a candidate technology for manufacturing thick welds for high-pressure vessels. A new mathematical formulation for calculating melting efficiency in square waveform arc welding is presented. The melting efficiency and the heat consumption are presented as a mathematical model of welding parameters, namely welding current, welding speed, current frequency, and electrode negativity (EN) ratio. The proposed approach is demonstrated through the welding of 2.25Cr-1Mo heat-resistant steel performed over a wide range of welding parameters. The investigation provides deeper insights into the interplay between process parameter, total heat consumption, and melting efficiency. The effect on flux consumption is also explained. The melting efficiency is inversely proportional to flux consumption. The welding heat does not necessarily promote the plate melting. Improper use of welding heat may lead to decreased melting efficiency and increased unwanted melting and consumption of welding flux. Compared to the conventional direct current (DC) power sources, the AC square waveform welding achieves almost the same order of melting efficiency with added advantages of better weld bead shape and flux consumption in a desirable range. The two additional parameters (frequency and EN ratio) of the AC square waveform power source provide more freedom to fine-tune the process and thereby efficiently use welding heat. The results of this investigation will be advantageous to the designers and fabricators of high-pressure vessels using AC square waveform welding. © 2020 by ASME

A resource-efficient process design for heavy fabrication: A case of single-pass-per-layer narrow gap welding

The welding process, omnipresent in the heavy fabrication industry, is a potential source of hazardous emissions. The article is motivated by the need to improve the sustainability of the heavy fabrication processes. Single-pass-per-layer narrow gap welding (NGW) is a potential alternative for reducing carbon footprint in high-thickness joints conventionally fabricated using the multi-pass multi-layers, sometimes even 100 or more layers, which is time-, material-, and energy- consuming. A newly developed mathematical model allows process design based on resource-efficient bead-on-plate welds (i.e., one layer deposited on a substrate). The results of bead-on-plate experiments are firstly utilized to identify the process capabilities in terms of strength, process, and production measures and subsequently coupled with the NGW mathematical model to arrive at feasible process parameters for a given groove design. The proposed approach implemented for a candidate case reveals significant improvement in the utilization of process capabilities, i.e., increase in strength, melting efficiency, and deposition rate and reduction in energy and material consumption. This investigation brings out three fundamental design rules for single-pass-per-layer NGW, namely i) the corresponding width of the bead-on-plate weld should be >1.5 times the groove width, ii) an upper limit on the utilization of process capabilities exists beyond which the productivity goes down drastically, and iii) the upper limit can be realized only at critical layer thicknesses. The design approach can be implemented to achieve more productive, economical, and sustainable design for processes involving high energy and material consumption. © 2022 The Author(s

A case of pulmonary pleomorphic carcinoma with preexisting interstitial pneumonia successfully treated with pembrolizumab

Pulmonary pleomorphic carcinoma is often refractory to chemotherapy and follows an aggressive clinical course. Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of advanced lung cancer, and a few cases with pleomorphic carcinoma have been reported to show tumor shrinkage after therapy with ICIs. When treating patients with ICIs, patient selection is essential, and monitoring and management of immune-related adverse events, including pneumonitis, are needed. We herein report a case of pulmonary pleomorphic carcinoma with preexisting interstitial pneumonia treated with pembrolizumab, antiprogrammed cell death 1 antibody. Our report highlights important considerations necessary when treating advanced pleomorphic carcinoma patients complicated with interstitial pneumonia. We also review the literature regarding the use of ICIs in such patients