On trace inequalities and their applications to noncommutative communication theory

Certain trace inequalities related to matrix logarithm are shown. These results enable us to give a partial answer of the open problem conjectured by A.S.Holevo. That is, concavity of the auxiliary function which appears in the random coding exponent as the lower bound of the quantum reliability function for general quantum states is proven in the case of $0\leq s\leq 1$.Comment: 8 page

A note on operator inequalities of Tsallis relative operator entropy

Tsallis relative operator entropy was defined as a parametric extension of relative operator entropy and the generalized Shannon inequalities were shown in the previous paper. After the review of some fundamental properties of Tsallis relative operator entropy, some operator inequalities related to Tsallis relative operator entropy are shown in the present paper. Our inequalities give the upper and lower bounds of Tsallis relative operator entropy. The operator equality on Tsallis relative operator entropy is also shown by considering the tensor product. This relation generalizes the pseudoadditivity for Tsallis entropy. As a corollary of our operator equality derived from the tensor product manipulation, we show several operator inequalities including the superadditivity and the subadditivity for Tsallis relative operator entropy. Our results are generalizations of the superadditivity and the subadditivity for Tsallis entropy.Comment: to appear in Linear Algebra App

Generalized Shannon inequalities based on Tsallis relative operator entropy

Tsallis relative operator entropy is defined and then its properties are given. Shannon inequality and its reverse one in Hilbert space operators derived by T.Furuta \cite{Fu:par} are extended in terms of the parameter of the Tsallis relative operator entropy. Moreover the generalized Tsallis relative operator entropy is introduced and then several operator inequalities are derived

Trace inequalities for products of matrices

In this short paper, we study some trace inequalities of the products of the matrices and the power of matrices by the use of elementary calculations

On trace inequalities and their applications to noncommutative communication theory

Certain trace inequalities related to matrix logarithm are shown. These results enable us to give a partial answer of the open problem conjectured by A.S. Holevo. That is, concavity of the auxiliary function which appears in the random coding exponent as the lower bound of the quantum reliability function for general quantum states is proven in the case of 0≦s≦1

Metabolic syndrome correlates intracoronary stenosis detected by multislice computed tomography in male subjects with sleep-disordered breathing

<p>Abstract</p> <p>Background</p> <p>Sleep-disordered breathing (SDB), especially obstructive sleep apnea (OSA), has frequent complications include hypertension, dyslipidemia and insulin resistance based on abdominal obesity or excess visceral fat (called Syndrome Z). OSA is a potential risk factor for cardiovascular diseases. The clinical characteristics of Japanese OSA subjects with OSA remain unclear. The present study investigated prevalence and predictive factors of intracoronary stenosis detected by multislice computed tomography (MSCT) in Japanese male subjects with SDB/OSA.</p> <p>Findings</p> <p>The study (O-VFStudy) subjects were 39 Japanese men with SDB/OSA who underwent all-night cardiorespiratory monitoring with fully attended polysomnography, and moreover both fat computed tomography (CT) scan and 64-row MSCT coronary angiography. The prevalence of coronary stenosis in this selected population with SDB/OSA was 15%. Logistic regression analysis showed a significant relationship between age-adjusted CAD and metabolic syndrome (<it>p </it>< 0.05), but not serum adiponectin levels and nocturnal fall in adiponectin. Subjects with the metabolic syndrome had significantly higher prevalence of CAD (31.3 versus 4.3%, <it>p </it>= 0.033), and lower levels of serum adiponectin (4.5 ± 0.6 versus 6.4 ± 0.6 μg/mL, <it>p </it>= 0.014), compared with groups without the metabolic syndrome.</p> <p>Conclusions</p> <p>The present study describes that the prevalence of greater than 50% intracoronary stenotic lesions detected by MSCT was 15% and the metabolic syndrome was correlated with intracoronary stenosis detected by MSCT in Japanese SDB/OSA subjects.</p> <p>Trial Registration</p> <p>UMIN 000002997</p> <p><url>https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000003633&language=E</url>.</p

5MHz PWM-controlled current-mode resonant DC-DC converter using GaN-FETs

In this paper, the method of the realization of a MHz level switching frequency DC-DC converter for high power-density is presented. For high power-density, Gallium Nitride field effect transistor (GaN-FET) and current-mode resonant DC-DC converter are adopted. In addition, the proposed pulse width modulation (PWM) control method which is suitable for the isolated current-mode resonant DC-DC converter operated at MHz level switching frequency, and the novel primary-side zero voltage switching (ZVS) turn on method for the proposed PWM control are presented. Some experiments have been done with 5MHz isolated DC-DC converter which has GaN-FET, and the total volume of the circuit is 16.14cm3. With the proposed PWM control method, input voltage range is 36-44V, and maximum load current range is 8A at Vi = 44V. The primary-side ZVS turn on is confirmed, and the maximum power-efficiency is 89.4%.7th International Power Electronics Conference, IPEC-Hiroshima - ECCE Asia 2014; Hiroshima; Japan; 18 May 2014 through 21 May 201

High frequency PWM-controlled current-mode resonant DC-DC converter with boost conversion

In this paper, a new pulse width modulation (PWM) control method for the isolated current-mode resonant converter with a fixed switching frequency is presented. The circuit topology is the same as a conventional resonant converter with synchronous rectification and without any additional components. The control technique for the output voltage regulation is proposed with the unique PWM control for synchronously-rectifying switches. By using the transformer\u27s leakage inductance and the PWM control, the boost conversion can be realized. Also, the zero-voltage switching (ZVS) operation can be done for primary switches, simultaneously. Some experiments have been done with 5MHz isolated DC-DC converter which has Gallium Nitride field effect transistor (GaN-FET).2013 15th European Conference on Power Electronics and Applications, EPE 2013; Lille; France; 2 September 2013 through 6 September 201

Five-Megahertz PWM-Controlled Current-Mode Resonant DC?DC Step-Down Converter Using GaN-HEMTs

High power efficiency and high power density are required in regulated isolated dc-dc converters. In this paper, a novel pulsewidth modulation (PWM) control method that is suitable for an isolated current-mode resonant dc-dc converter operated at a megahertz-level switching frequency is proposed. The output voltage with the proposed method can be regulated with no additional components at a fixed switching frequency. In addition, the zero-voltage switching (ZVS) of primary-side switches at turn on can be maintained. The principle of the proposed method and the method of the ZVS operation in the proposed method are explained. Some experiments have been performed with a 5-MHz isolated step-down dc-dc converter using gallium nitride high-electron-mobility transistors; the output voltage is 12 V, and the total volume of the circuit is 16.14 cm3. With the proposed PWM control method, the input voltage range is 42-45.5 V, and the maximum load current range is 10 A at Vi = 45.5 V. The ZVS of the primary-side switches at turn on is confirmed in all experimental regions, and the maximum power efficiency is 89.2%