168 research outputs found
F-term Moduli Stabilization and Uplifting
We study K\"ahler moduli stabilization in IIB superstring theory. We propose
a new moduli stabilization mechanism by the supersymmetry-braking chiral
superfield which is coupled to K\"ahler moduli in K\"ahler potential. We also
study uplifting of the Large Volume Scenario (LVS) by it. In both cases, the
form of superpotential is crucial for moduli stabilization. We confirm that our
uplifting mechanism does not destabilize the vacuum of the LVS drastically.Comment: 22 pages, 2 figure
Man, Communication, Being
Power Symposium, 2008. NAPS '08. 40th North American, University of Calgary, Calgary, Canada, Sept 28th to 30th, 2008Hybrid system reachability is applied to verification of fault release control in a power system. Fault release control is one strategy in emergency control and aims to mitigate an electrical stress of power system caused by disturbances. We introduce practical data in a fault release control of double machine-infinite bus (DMIB) system. The data is obtained using the RTDS and describes that the control is effective for prevention of transient instability in the DMIB system. By modeling of swing dynamics of the DMIB system as a hybrid automaton and reachability analysis of the automaton, we show that the control is correct for the prevention of transient instability
Regenerative Repair of Bone Defects with Osteoinductive Hydroxyapatite Fabricated to Match the Defect and Implanted with CAD, CAM, and Computer-Assisted Surgery Systems
Regenerative repair of large bone defects currently remains a challenging issue during surgery, owing to the limited regenerative ability of the bone. To address this issue, we attempted a precise repair of a bone defect using computer-aided procedures. Using pelvic computed tomography (CT) images of beagle dogs, virtual tumors were created in the pelvis using computer-aided design (CAD), and a bone resection following the margins of the bone tumor was performed on the CAD image. Hydroxyapatite (HA) implants to fill the bone defects and implants for shape evaluation of bone resection sites were designed and produced by computer-aided manufacturing and three-dimensional printing. Subsequently, using a computer navigation system, iliac bone defects were created in beagle dogs as preoperatively planned on CAD, filled with HA implants shaped to fit the bone defect sites, and coated with a recombinant human bone morphogenetic protein (rhBMP)-2-containing dough bone-forming material. Postoperative CT revealed that the new bone was formed around the implant over time. Anatomical healthy bone repair was confirmed to be completed 12 weeks after the surgery. These results demonstrate potential novel technology for efficacious and accurate repair of large bone defects without bone grafting
植物の防御物質の誘導機構の解明ならびに薬理効果の検証
東京理科大学201
Ordered Counterfactual Explanation by Mixed-Integer Linear Optimization
Post-hoc explanation methods for machine learning models have been widely
used to support decision-making. One of the popular methods is Counterfactual
Explanation (CE), also known as Actionable Recourse, which provides a user with
a perturbation vector of features that alters the prediction result. Given a
perturbation vector, a user can interpret it as an "action" for obtaining one's
desired decision result. In practice, however, showing only a perturbation
vector is often insufficient for users to execute the action. The reason is
that if there is an asymmetric interaction among features, such as causality,
the total cost of the action is expected to depend on the order of changing
features. Therefore, practical CE methods are required to provide an
appropriate order of changing features in addition to a perturbation vector.
For this purpose, we propose a new framework called Ordered Counterfactual
Explanation (OrdCE). We introduce a new objective function that evaluates a
pair of an action and an order based on feature interaction. To extract an
optimal pair, we propose a mixed-integer linear optimization approach with our
objective function. Numerical experiments on real datasets demonstrated the
effectiveness of our OrdCE in comparison with unordered CE methods.Comment: 20 pages, 5 figures, to appear in the 35th AAAI Conference on
Artificial Intelligence (AAAI 2021
Humidity Effects on Unsteady Characteristics of Supersonic Flow
In supersonic wind tunnels, the humidity content of the working fluid is known to have a significant effect on flow conditions in the test section. The intent of this paper is to evaluate the influence of moisture on the test section flow quality for the indraft supersonic wind tunnel located at the Muroran Institute of Technology. The static-pressure fluctuation is measured by means of an unsteady pressure sensor buried in a 10-degree-aperture cone model installed in the test section. The results show that supersonic flow at Mach 2 is contaminated by the self-sustained oscillation of a condensation shock wave for ambient relative humidity greater than approximately 50%. It is also found that for the Mach 2 flow, that the ratio of the static-pressure fluctuation to the dynamic pressure is less than 0.1%, if the absolute humidity is kept below a critical value of 2[g/m3]. Experimental observations also reveal that the three-dimensional boundary-layer transition process is hypersensitive to the influence of free-stream humidity.特集 : 航空宇宙機システム研究センターにおける開発研究2 : 4. オオワシII飛行にむけて並びに関連技術の研究開発(試験設備系
Spectropolarimetric Study on Circumstellar Structure of Microquasar LS I +61deg 303
We present optical linear spectropolarimetry of the microquasar LS I
+61 303. The continuum emission is mildly polarized (up to 1.3 %) and
shows almost no temporal change. We find a distinct change of polarization
across the H emission line, indicating the existence of polarization
component intrinsic to the microquasar. We estimate the interstellar
polarization (ISP) component from polarization of the H line and derive
the intrinsic polarization component. The wavelength dependence of the
intrinsic component is well explained by Thomson scattering in equatorial disk
of the Be-type mass donor. The position angle (PA) of the intrinsic
polarization represents the rotational axis of the Be disk.
This PA is nearly perpendicular to the PA of the radio jet found during
quiescent phases. Assuming an orthogonal disk-jet geometry around the compact
star, the rotational axis of the accretion disk is almost perpendicular to that
of the Be disk. Moreover, according to the orbital parameters of the
microquasar, the compact star is likely to get across the Be disk around their
periastron passage. We discuss the peculiar circumstellar structure of this
microquasar inferred from our observation and possible connection with its
high-energy activities.Comment: 17pages, 7figures; accepted for Publications of the Astronomical
Society of Japa
Ice Core Records of Antarctic Warming Events in the Last Glacial Period
第3回極域科学シンポジウム 横断セッション「海・陸・氷床から探る後期新生代の南極寒冷圏環境変動」11月26日(月) 国立国語研究所 2階講
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