Suzaku View of the Neutron Star in the Dipping Source 4U 1822−-37

The dipping X-ray source 4U 1822$-$37 was observed by Suzaku on 2006 Octrober 20 for a net exposure of 37 ks. The source was detected with the XIS at a 1-10 keV flux of 5.5$\times10^{-10}$ erg cm$^{-2}$ s$^{-1}$, and with the HXD (HXD-PIN) at a 10-50 keV flux of 8.9$\times10^{-10}$ erg cm$^{-2}$ s$^{-1}$. With HXD-PIN, the pulsation was detected at a barycentric period of 0.592437 s, and its change rate was reconfirmed as $-2.43\times$10$^{-12}$ s s$^{-1}$. The 1-50 keV spectra of 4U 1822-37 were found to be very similar to those of Her X-1 in the slopes, cutoff and iron lines. Three iron lines (Fe K$\alpha$, Fe XXV, and Fe XXVI) were detected, on top of a 1-50 keV continuum that is described by an NPEX model plus a soft blackbody. In addition, a cyclotron resonance scattering feature was detected significantly ($>99\%$ confidence), at an energy of 33$\pm$2 keV with a depth of 0.4$^{+0.6}_{-0.3}$. Therefore, the neutron star in this source is concluded to have a strong magnetic field of 2.8$\times10^{12}$ G. Further assuming that the source has a relatively high intrinsic luminosity of several times 10$^{37}$ erg s$^{-1}$, its spectral and timing properties are consistently explained

Coalition structure generation in cooperative games with compact representations

This paper presents a new way of formalizing the coalition structure generation problem (CSG) so that we can apply constraint optimization techniques to it. Forming effective coalitions is a major research challenge in AI and multi-agent systems. CSG involves partitioning a set of agents into coalitions to maximize social surplus. Traditionally, the input of the CSG problem is a black-box function called a characteristic function, which takes a coalition as input and returns the value of the coalition. As a result, applying constraint optimization techniques to this problem has been infeasible. However, characteristic functions that appear in practice often can be represented concisely by a set of rules, rather than treating the function as a black box. Then we can solve the CSG problem more efficiently by directly applying constraint optimization techniques to this compact representation. We present new formalizations of the CSG problem by utilizing recently developed compact representation schemes for characteristic functions. We first characterize the complexity of CSG under these representation schemes. In this context, the complexity is driven more by the number of rules than by the number of agents. As an initial step toward developing efficient constraint optimization algorithms for solving the CSG problem, we also develop mixed integer programming formulations and show that an off-the-shelf optimization package can perform reasonably well

胎生魚ウミタナゴ科魚類3種の交尾行動と社会構造に関する研究

第1章 緒言 第2章 ウミタナゴの交尾生態 第3章 アオタナゴの交尾生態 第4章 オキタナゴの交尾生態 第5章 日本産ウミタナゴ科魚類の交尾生態の比較 第6章 要約 第7章 謝辞 第8章 参考文献 第9章 SUMMARYMade available in DSpace on 2012-09-06T04:35:48Z (GMT). No. of bitstreams: 3 sakurai1.pdf: 10902720 bytes, checksum: 7e9f6723c63d82f57f3446a5f82f65c1 (MD5) sakurai2.pdf: 15700162 bytes, checksum: d21d883ee9c0b86a270953b13928116e (MD5) sakurai3.pdf: 6920238 bytes, checksum: 1ca1d524019d5e31791a423249520940 (MD5) Previous issue date: 1998-01-26主1-参

Stress Waves in Rocks and their Effects on Rock Breakage

In these experimental studies the authors have chiefly investigated the characteristics of the stress waves in rocks caused by detonators or explosives. The research consisted of two parts. In the first part, we have treated mainly the phenomena which accompany the detonator's attack and have discussed the dynamic characteristics of rocks under such impulsive loadings. The following results were obtained from this part of the investigation. The values of Young's moduli for rocks obtained dynamically are about two or three times greater than those obtained statically. The dynamic strengths of rocks are also greater than the static ones, but the difference seems to be not so great as in the case of metals. Moreover, it is an interesting result that various shock effects appear in accordance with the physical properties of rocks. In the second part we advanced to a study of the phenomena accompanying an explosive's attack and observed chiefly the changes in the propagation velocities of the induced stress waves near the explosion point. The results obtained can be summarized as follows. From the results obtained concerning the changes in the velocity of propagation of the stress waves with distance, a plastic wave of higher order seems to exist in the region very near the point of explosion and the appearance of the plastic wave seems to depend not only on the physical characteristics of the rocks but also on the brisance of the explosives. The compressibility of a rock under impulsive high pressure is peculiar to the physical properties of the rock, and it has no relation to the natures of the explosive. The peak pressure of the wave front decreases very rapidly with distance, and only within a few centimeters of the point of explosion do the explosives develop a different high pressure in proportion to their brisances

Term delivery choriocarcinoma patient with brain and lung metastases successfully treated by etoposide, methotrexate, actomycin D, cyclophosphamide and vincristine (EMA-CO) chemotherapy.

It is well known that antecedent term delivery and metastasis to sites other than the lungs and vagina are high risk factors for patients with gestational trophoblastic neoplasia. Here we report on a patient with choriocarcinoma who presented with brain and lung metastases after term delivery and was treated by EMA-CO chemotherapy. A 31-year-old woman delivered a healthy infant at term. Frequent episodes of hemoptysis occurred beginning 3 weeks after the delivery. On admission to our hospital, she had lesions in the uterus, lungs and brain as well as motor aphasia and hemiplagia. The pretreatment beta-hCG level was 21,000 ng/ml and the WHO score was 16 (high-risk group). The EMA-CO regimen was administrated as first-line chemotherapy and the patient achieved complete remission after 7 courses. Treatment was terminated after 11 courses and maintained with etoposide (25 mg/day) for 6 months. The patient has remained in complete remission for more than 16 years without other adjuvant therapies. We believe that EMA-CO can currently be considered the regimen of first choice for most high-risk patients with gestational trophoblastic neoplasia in view of its effectiveness and excellent tolerability.</p