380 research outputs found

    Remark on the Limit Case of Positive Mass Theorem for Manifolds with Inner Boundary

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    In [5] Herzlich proved a new positive mass theorem for Riemannian 3-manifolds (N,g)(N, g) whose mean curvature of the boundary allows some positivity. In this paper we study what happens to the limit case of the theorem when, at a point of the boundary, the smallest positive eigenvalue of the Dirac operator of the boundary is strictly larger than one-half of the mean curvature (in this case the mass m(g)m(g) must be strictly positive). We prove that the mass is bounded from below by a positive constant c(g),m(g)โ‰ฅc(g)c(g), m(g) \geq c(g), and the equality m(g)=c(g)m(g) = c(g) holds only if, outside a compact set, (N,g)(N, g) is conformally flat and the scalar curvature vanishes. The constant c(g)c(g) is uniquely determined by the metric gg via a Dirac-harmonic spinor.Comment: 12 pages, latex2

    Some extensions of the Einstein-Dirac equation

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    We considered an extension of the standard functional for the Einstein-Dirac equation where the Dirac operator is replaced by the square of the Dirac operator and a real parameter controlling the length of spinors is introduced. For one distinguished value of the parameter, the resulting Euler-Lagrange equations provide a new type of Einstein-Dirac coupling. We establish a special method for constructing global smooth solutions of a newly derived Einstein-Dirac system called the {\it CL-Einstein-Dirac equation of type II} (see Definition 3.1).Comment: 21page

    Relaxing Synchronization in Distributed Simulated Annealing

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    Simulated annealing is an attractive, but expensive, heuristic for approximating the solution to combinatorial optimization problems. Since simulated annealing is a general purpose method, it can be applied to the broad range of NP-complete problems such as the traveling salesman problem, graph theory, and cell placement with a careful control of the cooling schedule. Attempts to parallelize simulated annealing, particularly on distributed memory multicomputers, are hampered by the algorithmโ€™s requirement of a globally consistent system state. In a multicomputer, maintaining the global state S involves explicit message traffic and is a critical performance bottleneck. One way to mitigate this bottleneck is to amortize the overhead of these state updates over as many parallel state changes as possible. By using this technique, errors in the actual cost C(S) of a particular state S will be introduced into the annealing process. This dissertation places analytically derived bounds on the cost error in order to assure convergence to the correct result. The resulting parallel Simulated Annealing algorithm dynamically changes the frequency of global updates as a function of the annealing control parameter, i.e. temperature. Implementation results on an Intel iPSC/2 are reported

    Parallel Error Tolerance Scheme Based on the Hill Climbing Nature of Simulated Annealing

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    In parallelizing simulated annealing in a multicomputer, maintaining the global state S involves explicit message traffic and is a critical performance bottleneck. One way to mitigate this bottleneck is to amortize the overhead of these state updates over as many parallel state changes as possible. Using this technique introduces errors in the calculated cost C(S) of a particular state S used by the annealing process. Analytically derived bounds are placed on this error in order to assure convergence to the correct result. The resulting parallel simulated annealing algorithm dynamically changes the frequency of global updates as a function of the annealing control parameter, i.e., temperature. Implementation results on the Intel iPSC/2 are reporte

    Relaxing Synchronization in Distributed Simulated Annealing

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    This paper presents a cost error measurement scheme and relaxed synchronization method, for simulated annealing on a distributed memory multicomputer, which predicts the amount of cost error that an algorithm will tolerate. An adaptive error control method is developed and implemented on an Intel iPSC/

    Uterine and placental expression of TRPV6 gene is regulated via progesterone receptor- or estrogen receptor-mediated pathways during pregnancy in rodents

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    Transient receptor potential cation channel, subfamily V, member 6 (TRPV6) is an epithelial Ca2+ channel protein expressed in calcium absorbing organs. In the present study, we investigated the expression and regulation of uterine and placental TRPV6 during gestation in rodents. Uterine TRPV6 peaked at pregnancy day (P) 0.5, P5.5 and, P13.5 and was detected in uterine epithelium and glands of rats, while placental TRPV6 mRNA levels increased in mid-gestation. Uterine and placental TRPV6 mRNA levels in rats appear to cyclically change during pregnancy, suggesting that TRPV6 may participate in the implantation process. In addition, uterine TRPV6 mRNA is only expressed in placenta-unattached areas of the uterus, and uterine TRPV6 immunoreactivity was observed in luminal and glandular epithelial cells. In the placenta, TRPV6 was detected in the labyrinth and spongy zone. These results may indicate that TRPV6 has at least two functions: implantation of the embryo and maintenance of pregnancy. To investigate the pathway(s) mediating TRPV6 expression in rodents, anti-steroid hormone antagonists were injected prior to maximal TRPV6 expression. In rats, TRPV6 expression was reduced by RU486 (an anti-progesterone) through progesterone receptors, and ICI 182,780 (an anti-estrogen) blocked TRPV6 expression via estrogen receptors in mice. The juxtaposition of uterine and placental TRPV6 expressed in these tissues supports the notion that TRPV6 participates in transferring calcium ions between the maternal and fetal compartments. Taken together, TRPV6 gene may function as a key element in controlling calcium transport in the uterus between the embryo and the placenta during pregnancy

    Proposal of a New Scenario Composition Method for Escape Room Game Design

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    ๋ฆฌ์–ผ ๋ฐฉํƒˆ์ถœ ๊ฒŒ์ž„์€ (์ดํ•˜ ๋ฐฉํƒˆ์ถœ ๊ฒŒ์ž„) ๊ด€์ฐฐ๋ ฅ๊ณผ ์ฐฝ์˜๋ ฅ์„ ๋ฐœ์ทจํ•˜์—ฌ ํŒ€์› ๊ฐ„์˜ ์ƒํ˜ธ์ž‘์šฉ์„ ํ†ตํ•ด ์‹ค์ œ ๊ณต๊ฐ„์—์„œ ์ง„ํ–‰ํ•  ์ˆ˜ ์žˆ๋Š” ๊ฒŒ์ž„์œผ๋กœ์„œ ์ „ ์„ธ๊ณ„์ ์œผ๋กœ ๋งŽ์€ ์ธ๊ธฐ๋ฅผ ์–ป๊ณ  ์žˆ๋‹ค. ๋ณธ ๋…ผ๋ฌธ์€ ๋ฐฉํƒˆ์ถœ ๊ฒŒ์ž„ ๋””์ž์ธ์˜ ๊ธฐ๋ฐ˜์ด ๋˜๋Š” ์‹œ๋‚˜๋ฆฌ์˜ค ๊ตฌ์„ฑ ๋ฐฉ๋ฒ•์„ ์ œ์•ˆํ•˜๊ณ ์ž ํ•œ๋‹ค. ์ด๋ฅผ ์œ„ํ•ด ๋ฐฉํƒˆ์ถœ ๊ฒŒ์ž„์˜ ์ฒดํ—˜ ๋ฐ ๊ด€์ฐฐ ํ†ตํ•ด ์‚ฌ๋žŒ๋“ค์ด ์ฆ๊ฑฐ์›€์„ ๋Š๋ผ๋Š” ๊ณผ์ •์„ ์ดํ•ดํ•˜๊ณ  ์‹œ๋‚˜๋ฆฌ์˜ค ๊ตฌ์„ฑ ๊ณผ์ •์„ ์ •์˜ํ•œ ๋’ค ์‹œ๋‚˜๋ฆฌ์˜ค ์ดˆ์•ˆ์„ ์ž‘์„ฑํ•˜์—ฌ ์Šคํ† ๋ฆฌ๋ผ์ธ์„ ๊ฐ•์กฐํ•˜๋Š” ๋ฐฉํƒˆ์ถœ ๊ฒŒ์ž„์˜ ์‹œ๋‚˜๋ฆฌ์˜ค ๊ธฐ๋ณธ ์š”์†Œ์™€ ๊ตฌ์„ฑ ์›์น™์„ ์ œ์•ˆํ•˜์˜€๋‹ค.OAIID:RECH_ACHV_DSTSH_NO:A201701934RECH_ACHV_FG:RR00200003ADJUST_YN:EMP_ID:A080155CITE_RATE:FILENAME:hci2017_๋ฐฉํƒˆ์ถœ ๊ฒŒ์ž„ ๋””์ž์ธ์„ ์œ„ํ•œ ์‹œ๋‚˜๋ฆฌ์˜ค ๊ตฌ์„ฑ๋ฐฉ๋ฒ• ์ œ์•ˆ.pdfDEPT_NM:๋””์ž์ธํ•™๋ถ€EMAIL:[email protected]_YN:FILEURL:https://srnd.snu.ac.kr/eXrepEIR/fws/file/977abf52-2a2d-4bec-8817-4fb7e3ef54d7/linkCONFIRM:
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