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131.
Kataoka K. Itoh T. Okumura K. Suga T. 《Electronics Packaging Manufacturing, IEEE Transactions on》2007,30(3):194-199
A contact process between large-scale integration (LSI) pads and test probes at low contact force is a key to developing a probe card with smaller pitch and higher pin count. In this paper, we report on the characteristics of low-force contact methods on Cu electrodes. One is the fritting process, in which an electric breakdown is utilized to break the surface oxide, and the other is the heating treatment in hydrogen gas aimed at deoxidizing the surface Cu oxide. Conventional tungsten needle probes were used as testing probes, and contact resistances at low contact force of 1-5 mN were measured. Contact resistances smaller than 1 Omega were obtained by the fritting processes, in which the voltage and the current were 10 V and 280-320 mA, respectively. A deoxidization process at over 260degC was found to be effective for decreasing the contact resistance. The X-ray photoelectron spectroscopy (XPS) was utilized to investigate the surface state of hydrogen-treated Cu, and the deoxidization of Cu2O to Cu was observed in samples treated at 260degC, while no change was found in that at 150degC. 相似文献
132.
This paper proposes and demonstrates a numerical simulation method suitable to analyze the local damage and dynamic response of the structures composed of the reinforced concrete (RC) and/or the geological materials subjected to extremely severe loading by the energetic material like high explosives (HE). 相似文献
133.
Wada Yuichi Takagi Yoichiro Mori Teijiro Hamano Suenobu Miyamoto Toshio Itoh Toshio 《Industry Applications, IEEE Transactions on》1980,(1):30-39
The increase in electric power consumption in industry has led to the development of modern distribution systems such as control centers having high kVA ratings and high prospective fault current. In such a situation, the improvement of the system usefulness such as reliability and cost effectiveness is the essential requirement. An index is presented to evaluate the system usefulness using the cost effectiveness for fault protection in a system of given bank kVA. The index is estimated on four different system structures of control centers, including one which utilizes Permanent Power Fuses (PPF). It is presented that the PPF combined with molded case circuit breaker in main circuit effectively improves the cost effectiveness in control centers with high fault current. Operating principles of the PPF and the control center utilizing the PPF are briefly outlined. 相似文献
134.
Kenji Fukuzawa Hiroaki Tsuji Satoshi Hamaoka Mitsuhiro Shikida Shintaro Itoh Hedong Zhang 《Microsystem Technologies》2013,19(9-10):1567-1572
It is important to understand friction force in micro/nano mechanical devices both at high sliding speed and with high lateral resolution. Dual-axis friction force microscopes that can provide high lateral resolution and accuracy have been proposed; however, the sliding speed is limited by the probe scan speed. While a micro mechanical probe (MMP) with an electrostatic actuator can overcome this problem, details of probe design have not been established yet. This paper presents the principle of the mechanical design for an MMP with high force sensitivity and sufficient drive force. The dimensions of the double cantilever beam control the spring constants, resonant frequencies, and drive force. The use of an actuated MMP enables accurate friction force microscopy at high sliding speeds, which is required for the design of micro/nano mechanical devices. 相似文献
135.
Dong F. Wang Kohei Isagawa Takeshi Kobayashi Toshihiro Itoh Ryutaro Maeda 《Microsystem Technologies》2013,19(6):923-927
A passive (power-less), non-contact macro-scale piezoelectric bimorph DC current sensor to satisfy the increasing needs of DC power supply for monitoring the electricity consumption by either one-wire or two-wire appliance cord was proposed at our laboratory previously. In present study however, a MEMS-scale piezoelectric single-side DC current sensor, comprised of five parallel PZT plates, was further proposed and micro-fabricated for preliminarily examination. A micro magnet was fixed by manipulator onto the PZT cantilever tip to the theoretically pinpointed position of the center plate. Different from the results of the macro-scale piezoelectric bimorph DC current sensor, impulsive piezoelectric output voltages accompanying with a gradual decrease in decay were detected when the applied DC electric current was varied from 0.5 to 2.5 A. A linear relationship between the detected peak value of the impulse output voltage and the applied DC electric current was also obtained but with a higher slope compared to the result of the macro-scale piezoelectric bimorph DC current sensor. 相似文献
136.
137.
Shozo Miyazaki Akie Takahashi Kunihiko Itoh Mariko Ishitani Masatake Dairaku Mitsuo Togashi 《Drug development and industrial pharmacy》2013,39(7):780-787
Background: Oral sustained release gel formulations may provide a means of administering drugs to dysphagic and geriatric patients who have difficulties with handling and taking oral dosage forms. Aim: We have designed gel formulations for the oral administration of paracetamol with suitable rheological characteristics for ease of administration to patients with swallowing difficulties and sufficient integrity in the acidic environment of the stomach to achieve a sustained release of this drug. Method: Gels formed by gelatin, agar, gellan, pectin, and xyloglucan were assessed for suitable gel strength and in vitro and in vivo release characteristics. Results: Gellan (1.5%?w/v) and xyloglucan gels (1.5%?w/w) had acceptable gel strengths for ease of swallowing and retained their integrity in the rat stomach sufficiently well to sustain the release of paracetamol over a period of 6 hours. Comparison of 1.5%?xyloglucan gels with a commercially available preparation with identical paracetamol concentrations demonstrated improved sustained release properties of the xyloglucan gels. Conclusions: Gels formed by gellan and xyloglucan have suitable rheological and sustained release characteristics for potential use as vehicles for oral delivery of drugs to dysphagic patients. 相似文献
138.
Ken’ichiro Kita Masaki Narisawa Atsushi Nakahira Hiroshi Mabuchi Masayoshi Itoh Masaki Sugimoto Masahito Yoshikawa 《Journal of Materials Science》2010,45(1):139-145
The polymer blends of PCS (polycarbosilane) and PMHS-h (polymethylohydrosiloxane with high molecular weight) were prepared
by freeze-drying process of mixed benzene solution. Melt viscosity, mass loss, and gas evolution from prepared polymer blends
were analyzed. A polymer blend of HSah15 (15 mass% PMHS-h to PCS) was melt-spun to fiber form, curing by thermal oxidation
and pyrolyzed at various temperatures up to 1773 K. The obtained fibers were investigated by tensile tests, FE-SEM (field
emission scanning electron microscope) observation, and XRD (X-ray diffraction) analysis. After pyrolysis at 1273 K, there
were no pores in the cross section of the fiber derived from pure PCS; however, there were amounts of pores in the cross sections
of the fiber derived from HSah15. After pyrolysis at 1773 K, the coarse β-SiC (silicon carbide) crystals were formed on the
outside surface of the fiber derived from pure PCS; however, no remarkable β-SiC crystal were formed on the outside surface
of the fiber derived from HSah15. 相似文献
139.
Kiyoshi Minoura Shigeaki Mizushima Yasushi Asaoka Ichiro Ihara Eiji Satoh Sayuri Fujiwara Yasuhisa Itoh 《Journal of the Society for Information Display》2008,16(1):129-136
Abstract— A novel reflective color LCD without polarizers has been developed using a PDLC film and a retro‐reflector. Bright color images including moving images are achievable with ambient light. This novel LCD will enable the new application area of electronic paper. 相似文献
140.
A Mori S Tamura T Katsuno Y Nishimura T Itoh K Saheki H Takatsuka H Wada Y Fujimori T Okamoto Y Takemoto E Kakishita 《Canadian Metallurgical Quarterly》1999,6(1):55-58
STUDY OBJECTIVE: To evaluate the efficacy of conservative laparoscopic surgery in a series of patients with stage III-IV endometriosis. DESIGN: Prospective study (Canadian Task Force classification II-1). SETTING: University-affiliated hospital. PATIENTS: All 141 women who underwent conservative operative laparoscopy for stage III-IV endometriosis between January 1993 and December 1996 and were followed for a minimum of 6 months. INTERVENTIONS: Laparoscopic procedures performed with scissors, bipolar coagulation, and hydrodissection. MEASUREMENTS AND MAIN RESULTS: Clinical examination, transvaginal ultrasonography, and pain questionnaire were scheduled every 6 months postoperatively. The cumulative proportion of pregnant patients and cumulative recurrence rate were calculated by Kaplan-Meier method. Twenty-five women (44%) with infertility became pregnant. Twenty-three (51%) had stage III and two (16.7%, p <0.05) had stage IV endometriosis. The 24-month cumulative pregnancy rate was 57.5%. Thirty-one women (22%) reported pain recurrence during follow-up. Five (3.5%) recurrences were confirmed by histologic examination and eight (5.7%) were documented only by clinical and ultrasonographic findings. No recurrence occurred in the first 6 months of follow-up. CONCLUSION: Operative laparoscopy seems to be effective treatment for stage III endometriosis. A larger series with longer follow-up is necessary to clarify its role in the management of stage IV disease. (J Am Assoc Gynecol Laparosc 6(1):55-58, 1999) 相似文献