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Wear tests were conducted on hydrogen-free DLC coatings lubricated with engine oil containing carbon black (CB) in order to clarify their wear resistance. The influence of CB on accelerating wear was noticeable in the region where the minimum oil film thickness was less than the averaged secondary particle diameter of CB aggregates. According to a Raman spectroscopic analysis, the amount of DLC coating wear when lubricated in oil without CB tended to increase with increasing oil temperature and with an increasing Id/Ig ratio in the coating surface layer. In contrast, the Id/Ig ratio of the DLC coatings tested in oil containing CB tended to decrease, though the amount of DLC coating wear increased, which indicated a different wear mechanism.

The paper proposes the half-wave rectified brushless synchronous generator and analyzes the basic characteristics using the finite element method. It is based on the half-wave rectified excitation theory and doesn't need brush and slip ring system or permanent magnets for field excitation., 7th International Power Electronics Conference, IPEC-Hiroshima - ECCE Asia 2014; Hiroshima; Japan; 18 May 2014 through 21 May 2014, 2014 International Power Electronics Conference (IPEC-Hiroshima 2014 - ECCE-ASIA), pp.3024-3028; 2014

Diamond-like carbon (DLC) coatings have increased demand as protective hard coating for mechanical components due to their exceptional mechanical and tribological performance. They provide ultra-low friction, excellent anti-wear properties and adhesive protection. In recent years, researches focus on the use of DLC coatings under boundary lubricated contacts to increase fuel efficiency of automotive by controlling the friction and to reduce the emission of harmful elements. Commercially available fully formulated oils are designed for ferrous surfaces and contain various additives to enhance the base oils, but interaction between DLC surfaces and those formulated oils is not yet fully understood. In this study we investigated frictional properties of ta-C DLC coating when lubricated with a base oil poly alpha-olefin (PAO) and PAO containing friction modifier glycerol mono-oleate (GMO), anti-wear additives ZnDTP and mixture of GMO+ZnDTP to understand the mechanism of ultra-low friction. The results exhibit that ta-C give ultra-low friction in pure PAO for DLC/steel and DLC/DLC tribopair. GMO additivated PAO provide smooth run-in period for transition to ultra-low friction regime and also enhance the durability of coating. ZnDTP behave differently depending on the presence of ferrous surfaces on the contact. It forms pad-like wear protective tribofilm both on ta-C and steel surfaces for DLC/steel contact, while it form thin white layer on ta-C surfaces for DLC/DLC contact. Using GMO and ZnDTP together does not show any synergistic correlation for steel/steel, DLC/steel and DLC/DLC combinations.

Diamond-like carbon (DLC) coatings offer excellent mechanical and tribological properties. They provide ultra-low friction and superior wear resistance. In recent years, the research of DLC coating focuses on the application of these coating in mechanical components which work under boundary lubricated conditions. Since conventional lubricants and lubricant additives were formulated for metal surfaces, the effects of these lubricants on DLC contact and interaction between lubricant additives and DLC surfaces are still unclear. In this work, we present the influence of lubricant additives and counterbody materials on the wear behavior of ta-C DLC coating under boundary lubrication conditions. Tribological tests were performed in a home-build pin-on-disc tribometer. Atomic Force Microscopy (AFM), Field Emission Scanning Electron Microscopy (FESEM), Nano-indenter, X-ray Photoelectron Spectroscopy (XPS), Raman spectroscopy and scanning white light interferometry were used for characterization of ta-C DLC and worn surface analysis. The results show that ta-C DLC were totally wear out in DLC/steel contact tested in base oil. Addition of lubricant additives into the base oil significantly reduced the wear in the DLC/steel contact. ta-C DLC exhibited totally different wear behavior in DLC/steel and DLC/DLC contact depending on lubricant formulation. It is concluded that combination of lubricant formulation and counterbody material is a crucial factor for the use of DLC in lubricated conditions.

Hydrogen-free diamond-like carbon (DLC) coatings display markedly lower friction coefficients under a lubricated condition owing to the adsorption of oiliness agents and their decomposed components. This study examined the effect on friction properties of the sp2/sp3 bonding ratio of DLC coatings and the addition of nitrogen for improving surface wettability. Evaluations of friction properties under a lubricated condition showed that DLC coatings with a lower ratio of sp3 bonds and nitrogenated DLC coatings displayed higher friction coefficients. Results obtained by electron spin resonance revealed that adding nitrogen decreased the number of dangling bonds of DLC coatings in proportion to the sp3 bond ratio. Assuming that such dangling bonds are oiliness agent adsorption sites, it is concluded that adding nitrogen is not conducive to reducing friction coefficients.

The vehicle system is a multi-domain system, so that computer simulation technique has become an indispensable tool for vehicle system development. Our research group proposed a simulation modeling method based on the VHDL-AMS language. This paper describes how VHDL-AMS is used to model of vehicle fuel consumption simulation. We examine the influence of the power-network with electrical load and hill climb resistance in the vehicle running resistance.

Hydrogen-free diamond-like carbon (DLC) coatings were formed using four different deposition methods: trigger-type arc ion plating, laser-discharge-induced arc ion plating, filtered cathodic vacuum arc ion plating and magnetron sputtering. Wear tests were conducted on the coatings under a lubricated condition to investigate the effect of their surface hardness on wear, as well as the phase transformation from sp 3 to sp 2 and the influence of their surface properties. The results showed that DLC coating wear tended to decrease with higher hardness and that surface droplets (particles) formed during the deposition process tended to have the effect of increasing wear. Further wear testing was done using thicker coating samples to investigate the effect of the droplets in more detail. The results showed that abrasive wear tended to occur accompanying the falling out of droplets from inside the coating. An examination of such droplets by electron energy-loss spectroscopy using a transmission electron microscope (TEM-EELS) revealed that they originated from sputtered graphite debris that was not completely melted during the coating deposition process and served as the nucleus for droplet growth. Additionally, the structure of the droplet-coating interface was found to be a weak sp 2 -rich layer.

Objective The objectives of this study were to clarify changes in antimullerian hormone (AMH) concentrations during the menopausal transition and to determine whether AMH may serve as a marker to predict the onset of menopause. Methods Blood samples were collected annually for 6 years from 595 women living in Iwaki, Japan. We selected 44 women according to strict criteria: those older than 40 years at first participation; those who had their regular menstruation; those whose menstrual cycle had changed from regular to irregular or those who met the final menstrual period; and those who did not take medication that may affect the menstrual cycle. Serum AMH concentrations were determined by the newly developed AMH Gen II assay kit. Stage of the menopausal transition was defined according to the Stages of Reproductive Aging Workshop. Results Among the 44 women who participated in the study, 29 experienced menopause during the study (group A), whereas the remainder developed irregular menstrual cycles (group B). AMH was consistently found to be undetectable for 3 years before menopause, suggesting that AMH is a sensitive marker for predicting the onset of menopause. In addition, serum AMH was detectable at low levels in women from group B until menstrual cycles became irregular, suggesting that AMH serves as a marker for diagnosing the menopausal transition. Conclusions When AMH levels fall below detectable levels, women at the menopausal transition will progress to menopause within 3 years.

In this paper, a new digital hysteresis current control for ac-dc converters is presented. The new control circuit has the peak and valley current detectors which are comprised of an RC integrator, comparator and R-S flip-flop. These current detectors can detect the peak and valley reactor currents in real time. The proposed control circuit structure and the operation principle are explained with the simulation result. As a result, it is confirmed that both peak and valley currents are detected instantaneously using the proposed method.

Sensorless control technique is desired in applications of a long stroke linear synchronous motor (LSM) without using a linear scale. This paper discusses the development of a stator-magnetless LSM (no magnet mounted on the stator of LSM) for sensorless control technique that includes a high speed position estimation algorithm based on magnetic hysteresis phenomenon. This paper presents the new structure of a flux-switching LSM to achieve a high saliency ratio by designing a cutout which causes magnetic saturation in the armature core. The effect of sub-teeth to reduce cogging thrust is also presented. Furthermore, this paper also reports the analytical and experimental characteristics of inductance, thrust, cogging thrust, and sensorless control drive using a prototype.

Fractional Winding is used for permanent magnet type synchronous machine to improve the EMF form and cogging etc. This paper report the characteristics of q=1/2 and q=3/8 (q, 2011 International Conference on Electrical Machines and Systems, ICEMS 2011; Beijing; 20 August 2011 through 23 August 2011, ICEMS 2011, pp.1-6

This paper presents a design method for a linear synchronous motor with half-wave-rectified self-excitation; this method enables the construction of a motor with small thrust ripple. The mover of the motor is designed to be asymmetrical in order to reduce the thrust ripple. First, we design the configuration of the asymmetrical mover and the field winding of the mover by using the finite element method and a characteristic equation. The asymmetrical mover is built, and the thrust ripple reduction is verified by experiments. Next, the linear synchronous motor is modeled using a circuit simulator in order to confirm its high-speed performance. The operation characteristics are clarified by simulation. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(1): 43–52, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21051

The vehicle system is a multi-domain system that requires many branches of science and engineering. Therefore the development of the vehicle system requires the use of design methodologies that utilize simulations, which have grown increasingly sophisticated in recent years. This paper describes how VHDL-AMS was used to model the powertrain, alternator and battery system that are the basic elements of the vehicle power network system, and examines the simulation results with the aim of realizing a system simulation whose scope covers the entire vehicle., 2010 International Symposium on Power Electronics, Electrical Drives, Automation and Motion (SPEEDAM 2010) : Pisa, Italy, 2010.06.14-2010.06.16, SPEEDAM 2010, pp.1046-1051

To clarify what kind of risk factors predict incident fractures in patients treated with bisphosphonates, the authors investigated the relationship between baseline characteristics and incident vertebral fracture in Japanese osteoporosis patients undergoing bisphosphonate treatment. This was a multi-center follow-up study conducted at three centers, in which a total of 251 Japanese patients with osteoporosis (mean age 70.5 years) from the three centers were followed for 3.2 ± 2.0 years. Baseline data, including pre-existing fractures, bone mineral density in the lumbar spine (LBMD), bone metabolic markers, urinary pentosidine, and plasma homocysteine, were evaluated. Changes in LBMD, bone turnover markers, and incident fractures after the treatment were followed. Sixty-one patients developed incident vertebral fractures; this group of patients was older and had lower LBMD, a higher prevalent vertebral fracture number, and higher homocysteine and pentosidine levels than patients who did not develop incident vertebral fractures. Changes in LBMD, urinary N-terminal telopeptides of type I collagen (NTX), and bone-derived alkaline phosphatase showed no significant association with the occurrence of vertebral fractures. Cox's proportional hazard model demonstrated that age, prevalent fracture, pentosidine, and homocysteine were independent predictors of the incident vertebral fracture rate under bisphosphonate treatment. Higher baseline levels of pentosidine and homocysteine in osteoporosis patients are potential risk factors for incident vertebral fractures when these patients are treated with bisphosphonates. Further clarification is needed to explain why such patients have higher fracture susceptibility.

We have developed a low-speed and low-capacity wind power generator. In this paper, we introduce the outline of the 5kW multi-polar synchronous generator that generates the electric power efficiently from 50rpm to 180rpm. The generator is produced by a magnetic powder core for cost reduction. We also express the outline and field test results of the low-capacity power plant constructed in Ohmura City, Nagasaki.

This paper presents a design method for a linear synchronous motor with half-wave-rectified self excitation; this method enables the construction of a motor with small thrust ripple. The mover of the motor is designed to be asymmetrical for reducing the thrust ripple. First, we design the structure of the asymmetrical mover and the field winding of the mover by using the finite element method and a characteristic equation. The asymmetrical mover is built, and the thrust ripple reduction is verified by performing experiments. Next, the linear synchronous motor is modeled using a circuit simulator in order to confirm its high-speed performance. The operation characteristics are clarified by performing a simulation.

Aim: Hyaluronate plays an important role in the regulation of cervical function during parturition. In our previous study we showed that 4-methylumbelliferone (MU) suppresses hyaluronate synthesis by cultured human skin fibroblasts. The present study investigated the effects of MU on fibroblasts obtained from the human uterine cervix and assessed the possibility of controlling cervical ripening with MU. Methods: Human uterine cervical fibroblasts were collected from uterine cervices obtained from the uteri of three patients who had a total hysterectomy for uterine myoma at Hirosaki University Hospital. The fibroblasts were cultured in Dulbecco's modified Eagle's medium until confluence. They were then cultured in medium containing [3H]glucosamine (0.074 MBq/mL) with various MU doses. Hyaluronate synthesis was evaluated by assessing the incorporation of [3H]glucosamine into the soluble fraction of hyaluronate. Three independent studies were carried out on each specimen to clarify whether MU causes compositional changes or promotes hyaluronate degradation, whether the inhibitory effects of MU on hyaluronate synthesis are dose-dependent, and whether the effects of MU are reversible. Results: MU added to the medium of the cultured cells reduced the synthesis of hyaluronate in a dose-dependent manner. After MU was removed from the medium, hyaluronate synthesis recommenced, and the amount of [3H]hyaluronate synthesized was similar to the control level. Conclusions: MU inhibits the synthesis of hyaluronate in human uterine cervical fibroblasts.

This paper presents a new control method in order to improve the operation characteristics for a novel linear synchronous motor with half-wave rectified self excitation. First, we propose the new control method by addition of the reluctance thrust across full speed range for the novel linear synchronous motor. Then, the operation characteristics of the proposed control method are theoretically estimated and compared with the previous control method., International Conference on Electrical Machines and Systems, ICEMS 2007; Seoul; 8 October 2007 through 11 October 2007, ICEMS 2007, pp.1850-1853

A 3D boundary integral equation is applied to a model of a short-primary linear reluctance motor. The model is a double-sided construction where the primary member is surrounded by a set of secondary iron plates on both sides. Six kinds of different secondary geometries are calculated and their characteristics are discussed. For the confirmation of calculation results, a test machine is manufactured. Test results are compared with calculated ones. Furthermore, the static thrusts of a single-sided machine and a coreless PMLSM are measured and compared with those of the double-sided machine. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(1): 58–65, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20390

In the previous paper, we proposed a long-armature type novel linear synchronous motor with half-wave rectified self excitation. The field winding was short circuited with a diode and the armature winding was usual 3-phase windings. This paper presents a short-armature type novel linear synchronous motor applicable for a transport system. Compensated short pitch windings are proposed for the armature windings in order to decrease end effect., International Conference on Electrical Machines and Systems, ICEMS 2007; Seoul; 8 October 2007 through 11 October 2007, ICEMS 2007, pp.1513-1516

This paper presents an AC-AC power converter integrated with techniques that provide environmental harmony. The voltage source PWM inverter has been established as the major motor drive equipment. However, it is associated with issues pertaining to PWM switching as well as issues related to the input harmonics caused by capacitor input-type rectification. Hence, there is need for a converter that addresses these problems and provides an environmentally harmonious solution. The matrix converter has a topology that inherently exhibits sinusoidal input current waveforms and less stressful output voltage waveforms. Combining the matrix converter with certain filter topologies is shown to provide an environmentally harmonious solution. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(8): 1–10, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10129

A matrix converter has a topology that inherently exhibits sinusoidal input current waveforms and has small output voltage steps. This paper proposes to integrate the matrix converter with filters, which provide lower electromagnetic interference (EMI), lower common-mode current, lower shaft voltage, and sinusoidal output voltage waveforms. A salient aspect of the proposed integration is its ability to significantly reduce the value of the input EMI filter capacitors and still meet strict EMI regulations. This helps in reducing the ground leakage current, which in the past has been a serious limitation in applying EMI filters with low ground currents for human and cattle safety

This paper presents the principle and basic characteristics of a novel linear synchronous motor based on “half-wave rectified self excitation principle.” The field winding is short circuited through a diode and the armature winding consists of conventional three-phase windings. If the amplitude of the balance three-phase currents is modulated by an alternating wave with bias frequency, the produced magnetomotive force pulsates at the bias frequency and moves at the synchronous velocity. This pulsating magnetomotive force induces the electromotive force with a bias frequency in the field winding. The field excitation is obtained by rectifying the electromotive force with the diode in the field winding. In this paper, the authors design and build an experimental machine and confirm its basic characteristics. They also deduce the performance equations and investigate the thrust ripple reduction. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(1): 82–90, 2008; Published online in Wiley InterScience (www. interscience.wiley.com). DOI 10.1002/eej.20684

This paper presents a consideration about miniaturization of buck-boost dc-dc converter with the fast P control. From frequency characteristics, it is identified that fast P control method is useful to suppression of output capacitance and circuit miniaturization.

This research aims to examine the possibility of Switched Reluctance Motor (SRM) for the application to servo system. This paper proposes a position control at the arbitrary rotor position using measured torque curves. This proposed method is able to compensate the magnetic nonlinearity and manufacturing flaw, and realizes precision torque and position control. This paper verifies our proposed method through experimental results under various loads.

This paper studies the dynamics of the proposed vibration energy harvester to develop the method of designs and controls for the system. The harvester converts vibrational energy into electrical energy through rotational motion of a mechanical pendulum or a so-called parametric pendulum. The rotation is maintained for periodic vibration with appropriate amplitude and frequency. However, such appropriate vibration is not always supplied from nature. For this reason, reasonable energy conversion requires system designs including the electrical circuit for output power and control methods to establish and maintain the rotation against vibrations of nature. The study on the load characteristics of the system indicates the possibility to control the behavior of the mechanical pendulum by regulating the electrical load and to improve the mechanical characteristics by designing the load.

A novel synchronous generator has been developed for wind power generation. The generator does not require slip rings and brushes for field power supply as well as permanent magnets. The field flux is generated by the half-wave rectified excitation method. In this paper, the basic principle is explained. Then a test machine is produced and the performance characteristics are shown analytically and experimentally.

Recently development of the new concept motor for EV/HEV becomes very active. Due to the demands of expanding the high efficiency and controllable torque area, we proposed a novel Claw Pole Type Half-Wave Rectified Variable Field Flux Motor (CP-HVFM). This motor is simple and robust brushless structure and has variable field flux performance. This paper introduces the principle of variable field flux excitation method. And we evaluate an influence of the variable field flux on the torque and efficiency characteristics.

To decrease the switching loss and to reduce the surge voltage and current of a Matrix Converter (MC) using a high carrier frequency, the auxiliary resonant commutated pole (ARCP), a soft switching technique, is applied to a MC (ARCPMC). The ARCPMC system has an auxiliary switch linked to each output phase. The auxiliary switch generates the switching and conduction losses. This paper aims to examine by comparison the losses of ARCPMC with conventional MC through experimental and mathematical analysis.

Recently development of the new concept motor for EV or HEV becomes very active. The wider torque and speed controllable operating range and high efficiency under driving area are needed for traction motor. As a novel motor candidates, we proposed a novel Claw Pole Type Half-Wave Rectified Variable Field Flux Motor (CP-HVFM). This motor is simple and robust brushless structure and has variable field flux performance. This paper describes the influence of the rotor structure on the torque characteristic of CP-HVFM.

A novel segment type switched reluctance motor (SRM) is proposed, in which the segment core is embedded in aluminum (conductive metal) rotor block in order to increase the mechanical strength and easy manufacturing as well as to improve the performance characteristics and reduce the vibration and acoustic noise. The effect of design parameters on the average torque is investigated using the finite element method. Comparison with conventional VR type SRMs and segment type SRMs without conductive metal construction rotor show the proposed segment type SRM has advantages in the torque performances and the vibration and noise characteristics. The performance is also investigated by experiment.

In previous papers, we proposed the Cylindrical Rotor Type Switched Reluctance Motor (SRM), in which q-axis short-circuited windings were wound around the q-axis iron poles of the rotor and the stator windings were excited by the usual pulse current. It is confirmed experimentally that the short-circuited windings reduced the q-axis leakage flux and caused additional torque generation. In this paper we describe characteristic analysis of the new type SRM using the circuit simulation considering all the inductances coupled with the FEM analysis.

In this paper, we propose a new hybrid-type switched reluctance motor (SRM) with salient pole stator, which has a pair of permanent magnets attached symmetrically between the iron poles of the rotor. We describe experimental results not only on the basic characteristics of the hybrid SRM, but also characteristics with a current control loop under optimized advanced firing angle and cutoff angle control. Considerable improvement of machine performance, especially in the efficiency and power factor, for the hybrid SRM over the conventional VR-type SRM is confirmed. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(3): 72–79, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10285

In this paper, we propose a new Hybrid type SRM with salient pole stator, which has a pair of permanent magnets attached symmetrically between the iron poles of the rotor. The paper describes experimental results of not only basic characteristics of the Hybrid SRM but also characteristics with current control loop under optimized advanced firing angle and cut-off angle. Considerable improvement of machine performance, especially efficiency and power factor, in the Hybrid SRM over conventional VR type SRM is confirmed.

In our previous paper, we proposed a new sensorless elimination method for position control of an Interior Permanent Magne (IPM) motor, in which we utilize carrier frequency component current of PWM inverter as the motor position informatio source. In this paper we propose a new position estimation diagram and shows the experimental system together with the control results of the new position control method. With this control scheme, the motor speed has been successfully controlled from zero speed to 1, 400rpm (1.4 times rated speed) without mechanical sensor.

This paper verifies a proposed position control method under load condition. This proposed method realizes precision and quick torque and position control method for Switched Reluctance Motor (SRM). In order to compensate the magnetic nonlinearity and manufacturing flaw, the look-up tables in the torque controller are tabulated by measured torque curves. The experimental results show that the proposed method has the precision position control capability under load condition.

Recently development of the new concept motor for EV or HEV becomes very active. The wider torque and speed controllable operating range and high efficiency under driving area are needed for traction motor. As the new motor candidates, the novel motor with the variable motor constant, variable field flux and variable magnetized magnet are proposed by many universities and companies. In the previous paper, we proposed a half-wave rectified brushless synchronous motor using half-wave rectified variable field flux method. This motor is simple and robust brushless structure and has variable field flux performance. This paper describes a new Claw Pole Type Half-Wave Rectified Variable Field Flux Motor (CP-HVFM) and introduces the results of first-order design for prototype machine.

The purpose of this paper is to present a digital control method which suppresses the delay-time for the switching power supplies. The operation part of power supply has two controllers as the fast PD and the conventional PID, which are processed in parallel. Therefore, the fast PD control can improve the transient response of switching pulses. Obtained simulation results show that the proposed method can improve the transient response compared with the conventional PID control method. It is confirmed that 39% and 28% improvements have been obtained for undershoot and convergence time respectively.

Background: Hyaluronate plays an important role in the regulation of cervical function during parturition. In a previous study, we reported that 4-methylumbelliferone (MU) suppresses hyaluronate synthesis by cultured human skin fibroblasts. In the present study, the effect of MU on hyaluronate synthesis was investigated in cultured fibroblasts from the human uterine cervix. Methods: The cells were incubated with [3H]glucosamine in the presence of various concentrations of MU, and the effect of MU on hyaluronate synthesis was investigated. Then, the cells were preincubated in media that contained various concentrations of MU. After 72 h, the medium was removed and the cells were incubated with fresh medium containing [3H]glucosamine for 48 h. The amount of [3H]hyaluronate synthesized was measured. Results: MU added to the medium of cultured cells reduced the synthesis of hyaluronate in a dose-dependent manner. After MU was removed from the medium, hyaluronate synthesis recommenced and the amount of [3H]hyaluronate synthesized was similar to the control level. Conclusion: The MU-induced suppression of hyaluronate synthesis may contribute to the control of cervical ripening during human pregnancy.

Linear metro with single-sided linear induction motor (SLIM) propulsion and wheel-on-rail support and guidance came into service in April 1990 in Osaka and in December 1991 in Tokyo, and is under construction or planned for Yokohama, Kobe, and Fukuoka. Since the new traffic system is used widely, it is of great importance to decrease its energy consumption. In this paper, the design of the SLIM for the linear metro is formulated as a constrained nonlinear programming problem, and optimum design is carried out to maximize efficiency. Seven parameters are chosen as independent variables: number of poles, pole pitch, stack height, secondary aluminum sheet thickness, overhang length, slot width/slot pitch ratio, and rated slip. The output KW/input KVA ratio, maximum flux density in teeth, temperature rise, primary length, stack height, overhang length, maximum thrust, and vertical force are selected as constraint functions. In the optimization procedure, the performance characteristics are formulated by space harmonic analysis taking account of the end effect, skin effect, and air gap leakage. The accuracy of the formulas is verified against experimental results. Effective ways of increasing efficiency include the addition of a copper reaction plate and minimization of the mechanical clearance. © 2001 Scripta Technica, Electr Eng Jpn, 137(2): 36–43, 2001

The urinary bladder is lined by transitional epithelium, the glycocalyx on the luminal surface has interesting properties and is implicated in protective functions. Glycoconjugates are major components of the glycocalyx, but their biochemical nature is not well understood. Previous studies on rabbit bladder indicated the presence of significant levels of sialoglycoproteins compared to glycosaminoglycans in the epithelium. In this study, rabbit explant cultures were radiolabeled by precursor sugars or amino acids and a major lectin-reactive glycoprotein of rabbit bladder mucosa was isolated by affinity chromatography on jacalin-agarose. The radiolabeled glycoprotein was purified to homogeneity by a second cycle on the lectin column, followed by gel filtration and density gradient centrifugation. The average molecular mass of the glycoprotein was estimated to be 245 kDa and 210 kDa by gel filtration and SDS-PAGE, respectively. Its buoyant density was 1.40 g/ml, suggesting a carbohydrate content of approximately 50%. The percent distribution of glucosamine-derived tritium label in sialic acid, galactosamine, and glucosamine was 30, 52, and 18, respectively. The glycoprotein consisted entirely of small sialylated and neutral oligosaccharides O-glycosidically linked to serine and threonine residues. The same glycoprotein could be immunoprecipitated with an antibody against the carboxy terminal 17 amino acid peptide of human MUC1 mucin glycoprotein. This suggests that this mucin glycoprotein is the rabbit homolog of MUC1 glycoprotein, which has been previously established to be a component of human bladder urothelium and has been purified from human urine and biochemically characterized.