符号分割多元接続によるバケット通信に関する研究

本研究では移動体通信に適用可能な簡便で高効率な無線デ-タ通信の実現を目的として符号分割多元接続によるバケット通信(CDMA ALOHA方式)について検討を行い、以下のような研究成果が得られた. (1)CDMA U-ALOHA方式のスル-プットおよび遅延特性を解析的に求めた. (2)バケットの再送を考慮してCDMA U-ALOHA方式のスル-プットおよび遅延特性を解析的に求めた. (3)バケットの送信制御と再送制御の両方を行うOACPを提案し,これを用いたときのスル-プット特性を解析的に導出した. (4)アクセス制御を行う際に重要な問題であるアクセス制御遅延による影響を解析的に明らかにした. (5)アクセス制御遅延の影響を和らげることのできるMCLSPを提案した.MCLSPは伝搬距離が非常に長い静止衛星の場合にも特性の劣化が生じないので,衛生通信のようなアクセス制御遅延が非常に大きくなる場合にふさわしい方式であることがわかった. (6)セルラ-環境下におけるCDMA U-ALOHA方式のスル-プット特性をセグメント分割モデルを用いることにより解析的に求めた. 以上の研究成果は国内外の学会・論文等に公表した.これらは独創的な研究として高い評価を受けている.科学研究費補助金 研究種目:基盤研究(B)(2) 課題番号:07455160 研究代表者:小川 明 研究期間:1995-1996年度research repor

Observation of the ηc(2S) in Exclusive B→KKSK-π+ Decays

journal articl

地形や道路幅員、緑が住宅地の歩行空間の緑視率と印象評価に与える影響

departmental bulletin pape

Characterization of the Surface of AIkali Metaｌ-modified MgO by IR spectroscopy

application/pdfCO_2 gas was employed to characterize the surface of alkali metal-modified MgO by IR spectroscopy.　Doses of alkali metals changed the composition of CO_2-derived species　because of the enchanced basicity of the surfaces. Li showed the highest modification effect of the three alkali metals used ； this result was in the reverse order of electron-donating　ability. Taking inso account the fact that Li^+ can be substituted for Mg^^ due to their　similar sizes，and that alkali metal oxide and hydroxide were shown by XRD patterns， the　existence of an Li site strongly-connected with oxygen was considered.　The data from both lR spectra and TPD profiles leads to the possibility of quantitative evaluation of basicity of　the surface only by IR spectroscopy to a certain degree.departmental bulletin pape

Amphotropic liquid-crystalline behaviour of glycolipids in amino acid ionic liquids

We examined lyotropic liquid-crystalline behaviour of glycolipids (GLs) with a normal alkyl chain or a diacetylene-functionalised alkyl chain in several amino acid ionic liquids (AAILs). It was found that the mixtures of GL and AAIL form various nanosegregated liquid-crystalline phases, such as smectic, bicontinuous cubic and hexagonal columnar phases, depending on the two-component ratio and AAIL species. The observed liquid-crystalline behaviours were summarised as phase diagrams. It is noteworthy that the employment of amino acid anions with superior hydrogen-bonding ability, such as aspartic and glutamic acid anions, gives a phase diagram with a wide liquid-crystalline region. Comparing with a phase diagram obtained for the GL/water mixtures, we gained insights on the similarity/dissimilarity between water and AAILs as self-organisation media of amphiphiles. For the diacetylene-functionalised molecule, UV irradiation was carried out to progress polymerisation. It is of interest that the polymerisation reaction progressed when the glycolipid formed a smectic phase in an AAIL while a reaction progress was not found when it formed a bicontinuous cubic phase in another AAIL. We believe that AAILs have a great potential to be a liquid media not only for amphiphiles but for various functional materials, such as polymers and colloids, to form novel assemblies.</p

SOCS1 physically interacts with RhTRIM5α.

<p>HEK293T cells were co-transfected with 1.0 µg of pRhTRIM5α-HA and 2.0 µg of pHuSOCS1. The total amount of plasmids transfected was adjusted to 3.0 µg per sample with pcDNA3.1. Two days post-transfection, whole cell lysates were subjected to immunoprecipitation for RhTRIM5α with anti-HA antibody. Input lysates (left panels) and precipitated proteins (right panels) were separated by SDS-PAGE and proteins were detected by immunoblot analyses with anti-SOCS1 (upper panels) and anti-HA (RhTRIM5α-HA, lower panels) antibodies.</p

The effects of African green and cynomolgus monkey TRIM5α C-terminal sequences on TRIM5αrh-mediated HIV-1 late restriction activities.

<p>(A) Schematic representation of the chimeric TRIM5α constructs between rhesus monkey (Rh, filled), African green monkey (Ag, hatched) and cynomolgus (Cy, dotted) TRIM5α proteins. (B) Western blot analysis of chimeric TRIM5α proteins A/R, R/A and R/C following transfection into 293T cells. Arrow indicates approximate full-length TRIM5α size. (C) Late-restriction activities of chimeric TRIM5α proteins upon co-transfection with pNL4-3 into 293T cells. Viral titers were determined in GHOST(3)R3X4R5 indicator cells and reported as infectious units per ml (IU/ml). Error bars indicate one standard deviation.</p

Antiviral activities of chimeric TRIM5α proteins against HIV-1 production.

<p>(A) Schematic representation of the chimeric TRIM5α constructs between human (Hu), rhesus monkey (Rh), African green monkey (Ag) and cynomolgus monkey (Cy) TRIM5α proteins. (B) Upper panel: late-restriction activities of chimeric TRIM5α proteins upon co-transfection with pNL4-3 into 293T cells. Viral titers were determined in GHOST(3)R3X4R5 indicator cells and reported as infectious units per ml (IU/ml). Error bars indicate one standard deviation. Lower panel: western blot analysis of chimeric TRIM5α proteins following transfection into 293T cells. Arrow indicates approximate full-length TRIM5α size.</p

TRIM5α orthologue expression in 293T cells and antiviral spectrum of TRIM5α orthologues against lentiviral production.

<p>(A) Verification of the proper expression of TRIM5α orthologues. Control plasmid (−), TRIM5αhu (Hu), TRIM5αrh (Rh), TRIM5αag (Ag) and TRIM5αcy (Cy) expression in transfected 293T cells were verified via immunoblot analysis. Arrow depicts approximate TRIM5α band size. (B) 293T cells were co-transfected with a primate lentivirus proviral plasmid and increasing amounts of human (Hu), rhesus monkey (Rh), African green monkey (Ag) or cynomolgus monkey (Cy) TRIM5α-expressing plasmids. As infectious proviral plasmids, HIV-1 Group M (pNL4-3 and p89.6), HIV-1 Group O (pCMO2.41, pCMO2.5), HIV-2 (pROD10), and SIV (pSIV_MAC1A11, pSIV_AGMTan-1 and pSIV_AGMSAB-1) were used. Viral titers were determined in GHOST(3)R3X4R5 indicator cells and described as infectious units per ml (IU/ml). Error bars indicate one standard deviation.</p