Speed Control of a DC Motor System through Delay Time Variant Network

Kenshi Matsuo,Takeshi Miura,Toshiyuki Taniguchi 제어로봇시스템학회 2006 제어로봇시스템학회 국제학술대회 논문집 Vol.2006 No.10

HOMOTOPY FIXED POINT SETS AND ACTIONS ON HOMOGENEOUS SPACES OF p-COMPACT GROUPS

Kenshi Ishiguro,Lee, Hyang-Sook Korean Mathematical Society 2004 대한수학회지 Vol.41 No.6

We generalize a result of Dror Farjoun and Zabrodsky on the relationship between fixed point sets and homotopy fixed point sets, which is related to the generalized Sullivan Conjecture. As an application, we discuss extension problems considering actions on homogeneous spaces of p-compact groups.

Modular invariants under the actions of some reflection groups related to Weyl groups

Kenshi Ishiguro,Takahiro Koba,Toshiyuki Miyauchi,Erika Takigawa 대한수학회 2020 대한수학회보 Vol.57 No.1

Some modular representations of reflection groups related to Weyl groups are considered. The rational cohomology of the classifying space of a compact connected Lie group $G$ with a maximal torus $T$ is expressed as the ring of invariants, $H^*(BG; \Q)\cong H^*(BT; \Q)^{W(G)}$, which is a polynomial ring. If such Lie groups are locally isomorphic, the rational representations of their Weyl groups are equivalent. However, the integral representations need not be equivalent. Under the mod $p$ reductions, we consider the structure of the rings, particularly for the Weyl group of symplectic groups $Sp(n)$ and for the alternating groups $A_n$ as the subgroup of $W(SU(n))$. We will ask if such rings of invariants are polynomial rings, and if each of them can be realized as the mod $p$ cohomology of a space. For $n=3, 4$, the rings under a conjugate of $W(Sp(n))$ are shown to be polynomial, and for $n=6, 8$, they are non--polynomial. The structures of $H^*(BT^{n-1}; \F_p)^{A_n}$ will be also discussed for $n=3, 4$.

INVARIANT RINGS AND DUAL REPRESENTATIONS OF DIHEDRAL GROUPS

Kenshi Ishiguro 대한수학회 2010 대한수학회지 Vol.47 No.2

The Weyl group of a compact connected Lie group is a reflection group. If such Lie groups are locally isomorphic, the representations of the Weyl groups are rationally equivalent. They need not however be equivalent as integral representations. Turning to the invariant theory,the rational cohomology of a classifying space is a ring of invariants,which is a polynomial ring. In the modular case, we will ask if rings of invariants are polynomial algebras, and if each of them can be realized as the mod p cohomology of a space, particularly for dihedral groups.

Clinical Application of Magnifying Endoscopy with Narrow-Band Imaging in the Stomach

Kenshi Yao 대한소화기내시경학회 2015 Clinical Endoscopy Vol.48 No.6

Magnifying endoscopy with narrow-band imaging (M-NBI) can visualize superficial microanatomies in the stomach. The normal morphology of the microanatomy visualized by M-NBI differs according to the part of the stomach. The gastric fundic glandular mucosa appears as a regular honeycomb-like subepithelial capillary network (SECN) pattern with a regular collecting venule pattern and regular oval crypt opening with circular marginal crypt epithelium (MCE) pattern. The gastric pyloric glandular mucosa displays a regular coil-shaped SECN pattern and regular polygonal or curved MCE pattern. For a diagnosis of early gastric cancer using M-NBI, the vessel plus surface classification system was developed. This system is clinically useful for the differential diagnosis of focal gastritis and small depressed cancer and for determining the horizontal extent of early gastric cancer for successful endoscopic resection. Advantages of M-NBI over conventional endoscopic imaging techniques with white light include accurate diagnosis and cost effectiveness. This technique is a breakthrough in the endoscopic diagnostic field.

Optical Microangiography: High-Definition Magnification Colonoscopy with Narrow Band Imaging (NBI) for Visualizing Mucosal Capillaries and Red Blood Cells in the Large Intestine

( Kenshi Yao ),( George K. Anagnostopoulos ),( Aida U. Jawhari ),( Philip V. Kaye ),( Chris J. Hawkey ),( Krish Ragunath ) 대한소화기기능성질환·운동학회 2008 Gut and Liver Vol.2 No.1

Background/Aims: Recent advances in zoom endoscopy have enabled the subepithelial capillary network (SECN) in different organs of the gastrointestinal tract to be visualized. Ex vivo studies have suggested that the SECN demonstrates a honeycomb-like structure in the large intestine, but this has not yet been visualized in vivo. The high clarity and resolution of narrow-band imaging (NBI) may allow visualization at the single red-blood-cell (RBC) level and more accurate visualization of the SECN. We investigated whether high-definition magnification colonoscopy with NBI is useful for visualizing capillaries and RBCs in the large intestine. Methods: Sixteen patients with bowel symptoms undergoing routine colonoscopy with normal findings in a tertiary referral academic gastroenterology and endoscopy unit were included in the study. Total colonoscopies were performed using a high-definition magnification colonoscope (CF-H260AZI, Olympus, Tokyo) and a prototype high-definition electronic endoscopy system capable of NBI. Each part of the large intestine (cecum, ascending, transverse, descending, and sigmoid colon, and rectum) was observed at the maximum magnification with white-light imaging (WLI) and NBI. The normal honeycomb-like SECN and RBC movement by high-definition magnification colonoscopy with either WLI or NBI was prospectively successfully visualized for each part of the large intestine. Results: In all subjects, high-definition magnification colonoscopy with NBI allowed the visualization of a honeycomb-like SECN together with RBC movement in each segment of the large intestine except for the rectum. In contrast, with WLI alone, neither this SECN structure nor RBC movement could be detected. Conclusions: High-definition magnification colonoscopy with NBI could be a new optical method for facilitating noninvasive investigations of both the microvascular architecture and microcirculation without the need for contrast materials. (Gut and Liver 2008; 2:14-18)

Present State of Membrane Structures in Japan

Oda, Kenshi Korean Association for Spatial Structures 2002 한국공간구조학회지 Vol.2 No.2

Formerly, it was called a tent and now, it is called membrane structure. If saying a tent, it imagines the tent of Bedouin, Mongolia and North American Indian. It became clear from the excavated wall painting that have been covered with the retractable roof of the canvas on the auditorium at the amphitheater in Pompeii and became a topic. These tents were made of the animal skins or fabric woven with the flax plants, and these tents are still used. However, if saying membrane material at present, it says the one to have applied a coating resin to the textile. Because the base fabric of membrane material is a woven fabric, the relation between the stress and the strain is different to the direction of the weaving thread. Moreover, the tensile force must always occur in the membrane surface. From these reasons, because the membrane structure corresponds to the particular building material and the construction method about the Building Standard Law, it must be examined specially that the membrane structural building have the same or any more safety as the provisions which was set to the Building Standard Law. Therefore, the technical standards about the membrane structural building became indispensable. In the paper, the kinds of the membrane materials, which are used for the membrane structural buildings, and technical standards process of the creating for the membrane structure buildings are introduced. Lastly, some of the soccer stadiums for 2002 FIFA World Cup KOREA/JAPAN which be covered with the roof of the membrane structures are presented.

MODULAR INVARIANTS UNDER THE ACTIONS OF SOME REFLECTION GROUPS RELATED TO WEYL GROUPS

Ishiguro, Kenshi,Koba, Takahiro,Miyauchi, Toshiyuki,Takigawa, Erika Korean Mathematical Society 2020 대한수학회보 Vol.57 No.1

Some modular representations of reflection groups related to Weyl groups are considered. The rational cohomology of the classifying space of a compact connected Lie group G with a maximal torus T is expressed as the ring of invariants, H*(BG; ℚ) ≅ H*(BT; ℚ)^W(G), which is a polynomial ring. If such Lie groups are locally isomorphic, the rational representations of their Weyl groups are equivalent. However, the integral representations need not be equivalent. Under the mod p reductions, we consider the structure of the rings, particularly for the Weyl group of symplectic groups Sp(n) and for the alternating groups A_n as the subgroup of W(SU(n)). We will ask if such rings of invariants are polynomial rings, and if each of them can be realized as the mod p cohomology of a space. For n = 3, 4, the rings under a conjugate of W(Sp(n)) are shown to be polynomial, and for n = 6, 8, they are non-polynomial. The structures of H*(BT^n-1; 𝔽_p)^A_n will be also discussed for n = 3, 4.

INVARIANT RINGS AND DUAL REPRESENTATIONS OF DIHEDRAL GROUPS

Ishiguro, Kenshi Korean Mathematical Society 2010 대한수학회지 Vol.47 No.2

The Weyl group of a compact connected Lie group is a reflection group. If such Lie groups are locally isomorphic, the representations of the Weyl groups are rationally equivalent. They need not however be equivalent as integral representations. Turning to the invariant theory, the rational cohomology of a classifying space is a ring of invariants, which is a polynomial ring. In the modular case, we will ask if rings of invariants are polynomial algebras, and if each of them can be realized as the mod p cohomology of a space, particularly for dihedral groups.

OKAYAMA ASTROPHYSICAL OBSERVATORY WIDE-FIELD CAMERA

YANAGISAWA KENSHI The Korean Astronomical Society 2005 Journal of The Korean Astronomical Society Vol.38 No.2

We present the design, expected performance, and current status of the wide field near-infrared camera (OAOWFC) now being developed at Okayama Astrophysical Observatory, NAOJ, NINS. OAOWFC is a near-infrared survey telescope whose effective aperture is 91cm. It works at Y, J, H, and $K_s$ bands and is dedicated to the survey of long period variable stars in the Galactic plane. The field of view is $0.95 {\times} 0.95 deg^2$ which is covered by one HAWAII-2 RG detector of 2048 ${\times}$ 2048 pixels with the pixel size of $18.5 {\mu}m\;{\times}\;18.5{\mu}m$, that results in the sampling pitch of 1.6 arcsec/pixel. OAOWFC can sweep the area of $840 deg^2$ every 3 weeks, attaining a limiting magnitude of 13 in $K_s$ band. It allows us to observe long period variables embedded in the Galactic plane where interstellar extinction is severe in optical.