• Title/Summary/Keyword: excess pulse

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Characterization of Ferroelectric $SrBi_2Ta_2O_9$ Thin Films Deposited by RF Magnetron Sputtering With Various Annealing Temperatures (RF magnetron sputtering으로 제조된 강 유전체 $SrBi_2Ta_2O_9$ 박막의 열처리 온도에 따른 특성 연구)

  • 박상식;양철훈;윤순길;안준형;김호기
    • Journal of the Korean Ceramic Society
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    • v.34 no.2
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    • pp.202-208
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    • 1997
  • Bi-layered SrBi2Ta2O9(SBT) films were deposited on Pt/Ti/SiO2/Si sibstrates by rf magnetron sputt-ering at room temperature and then were annealed at 75$0^{\circ}C$, 80$0^{\circ}C$ and 85$0^{\circ}C$ for 1 hour in oxygen at-mosphere. The film composition of SrBi2Ta2O9 was obtained after depositing at room temperature and annealing at 80$0^{\circ}C$. Excess 20mole% Bi2O3 and 30 mole% SrCO3 were added to the target to compensate for the lack of Bi and Sr in SBT film. 200 nm thick SBT film exhibited and dense microstructure, adielectric constant of 210, and a dissipation factor of 0.05 at 1 MHz frequency. The films exhibited Curie temperature of 32$0^{\circ}C$ and a dielectric constant of 314 at that temperature under 100 kHz frequency. The remanent polarization(2Pr) and the coercive field(2Ec) of the SBT films were 9.1 $\mu$C/$\textrm{cm}^2$ and 85 kV/cm at an applied voltage of 3V, resspectively and the SBT film showed a fatigue-free characteristics up to 1010 cy-cles under 5V bipolar pulse. The leakage current density of the SBT film was about 7$\times$10-7A/$\textrm{cm}^2$ at 150 kV/cm. Fatigue-free SBT films prepared by rf magnetron sputtering can be suitable for application to non-volatile memory device.

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Chemical Analysis and Thermoelectric Properties of the PbSnTe Semiconductors (화학조성에 따른 PbSnTe계 반도체의 열전특성조사)

  • Oh, Kyu-Whan;Oh, Seung-Mo
    • Applied Chemistry for Engineering
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    • v.1 no.1
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    • pp.83-90
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    • 1990
  • The semiconducting $(Pb_1\;_xSn_x)_1$ $_yTe_y$, one of the low - temperature thermoelectric materials, has been prepared and its chemical composition and nonstoichiometry has been analyzed. The content of Pb in the specimens was determined by the complexometric back - titration method with EDTA and Pb(II) standard solutions. Te - content was analyzed with the redox titration method. The electrical conductivity and the thermoelectric power have also been measured by the DC 4 - probe and the heat-pulse technique, respectively. All of the specimens showed a nonstoichiometric behavior in their chemical compositions (Te excess), thus gave rise to a p - type semiconducting property, and the nonstoichoimetry became bigger as the Sn - content increased. The thermoelectric power vs. temperature results have been analyzed upon the basis of the Fermi level vs. temperature profiles in the saturation regime. The specimen of x=0.1 evolved a transition from p - to n - type property at about 670K, which has been explained by the fact that the mobility of electrons is bigger than that of holes in the temperature range of the intrinsic regime.

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Directivity Analysis of Ultrasonic Wave Reflected from the Artificial Defect in Simulated Butt Welded Joint (가상 용접부내의 결함으로부터 반사된 초음파의 지향성 해석)

  • Nam, Young-Hyun
    • Journal of the Korean Society for Nondestructive Testing
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    • v.15 no.2
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    • pp.378-385
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    • 1995
  • The ultrasonic non-destructive testing uses the directivity of the ultrasonic pulse wave which propagates in one direction. The directivity is expressed as the relationship between the propagate direction and its sound pressure. The directivity of ultrasonic wave is closely related to determination of probe arrangement, testing sensitivity, scanning pitch and defect location and characterization. The paper measured the directivity of shear wave, which reflected from artificial defect located in weld metal zone in butt welded joint similar model made of pyrex glass by using visualization method. 2 MHz and 4 MHz angle probes were used to measure the directivity of reflection wave at the artificial defect. The directivity of shear waves reflected from the defect was different according to the probe position and the shape of butt welded joint. The difference of directivity of reflection wave was existed between 2 MHz and 4 MHz angle probes. The angle of reflection wave became equal to angle of incidence as increase of the height of excess metal.

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Experimental investigation of Scalability of DDR DRAM packages

  • Crisp, R.
    • Journal of the Microelectronics and Packaging Society
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    • v.17 no.4
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    • pp.73-76
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    • 2010
  • A two-facet approach was used to investigate the parametric performance of functional high-speed DDR3 (Double Data Rate) DRAM (Dynamic Random Access Memory) die placed in different types of BGA (Ball Grid Array) packages: wire-bonded BGA (FBGA, Fine Ball Grid Array), flip-chip (FCBGA) and lead-bonded $microBGA^{(R)}$. In the first section, packaged live DDR3 die were tested using automatic test equipment using high-resolution shmoo plots. It was found that the best timing and voltage margin was obtained using the lead-bonded microBGA, followed by the wire-bonded FBGA with the FCBGA exhibiting the worst performance of the three types tested. In particular the flip-chip packaged devices exhibited reduced operating voltage margin. In the second part of this work a test system was designed and constructed to mimic the electrical environment of the data bus in a PC's CPU-Memory subsystem that used a single DIMM (Dual In Line Memory Module) socket in point-to-point and point-to-two-point configurations. The emulation system was used to examine signal integrity for system-level operation at speeds in excess of 6 Gb/pin/sec in order to assess the frequency extensibility of the signal-carrying path of the microBGA considered for future high-speed DRAM packaging. The analyzed signal path was driven from either end of the data bus by a GaAs laser driver capable of operation beyond 10 GHz. Eye diagrams were measured using a high speed sampling oscilloscope with a pulse generator providing a pseudo-random bit sequence stimulus for the laser drivers. The memory controller was emulated using a circuit implemented on a BGA interposer employing the laser driver while the active DRAM was modeled using the same type of laser driver mounted to the DIMM module. A custom silicon loading die was designed and fabricated and placed into the microBGA packages that were attached to an instrumented DIMM module. It was found that 6.6 Gb/sec/pin operation appears feasible in both point to point and point to two point configurations when the input capacitance is limited to 2pF.

Reaction of Cr Atoms with O2 at Low Pressures: Observation of New Chemiluminescence Bands from CrO2*

  • Son, Hyung-Su;Ku, Ja-Kang
    • Bulletin of the Korean Chemical Society
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    • v.25 no.2
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    • pp.226-232
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    • 2004
  • Ground and low-lying electronic states of Cr atoms in the gas phase were generated from photolysis of $Cr(CO)_6$ vapor in He or Ar using an unfocussed weak UV laser pulse and their reactions with $O_2$ and $N_2O$ were studied. When 0.5-1.0 Torr of $Cr(CO)_6$ /$O_2$ /He or Ar mixtures were photolyzed using 295-300 nm laser pulses, broadband chemiluminescence peaked at ~420 and ~500 nm, respectively, was observed in addition to the atomic emissions from $z^7P^{\circ}$, $z^5P^{\circ}$, and $y^7P^{\circ}$ states of Cr atoms. When $N_2O$ was used instead of $O_2$, no chemiluminescence was observed. The chemiluminescence intensities as well as the LIF intensities for those three low-lying electronic states ($a^7S_3,\;a^5S_2\;and\;a^5D_J$) showed second-order dependence on the photolysis laser power. Also, the chemiluminescence intensities were first-order in $O_2$ pressure, but the presence of excess Ar showed a strong inhibition effect on them. Based on the experimental results, the chemiluminecent species in this work is attributed to $CrO_2^*$ generated from hot ground state Cr atoms with $O_2$. The apparent radiative lifetimes of the chemiluminescent species and collisional quenching rate constants by $O_2$ and Ar also were investigated.

Comparison of Electrodermal Activity between Hypertensive and Non-hypertensive Subject in Health Screening Population (건강검진자 대상 고혈압 유무에 따른 피부전기활동성 비교 연구)

  • Kim, Young Eun;Kim, Chul;Yea, Sang Jun;Yang, Chang Sop;Song, Mi Young
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.6
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    • pp.847-852
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    • 2013
  • The aim of this study was to investigate the difference of electrodermal activity between the hypertensive and non-hypertensive subjects. A total 161 subjects who visited a hospital for health check ups from August 2011 through November 2011 and from September 2012 through November 2012 were included in this study. We divided the subjects into two groups by blood pressure, hypertension group(81 patients) and non-hypertension group(180 subject). Then we compared electrodermal activity between two groups by using the autonomic bioelectric response device model CP-6000A. The data was analyzed by independent t-test and logistic regression. In this study, there was a significant difference in electrodermal activity(the mean absolute value of positive, negative pulse conductivity) between hypertensive and normotensive group in t-test and electrodermal activity showed the significant influence on the prevalence risk of hypertension with age, body mass index and dyslipidema in binominal logistic regression. In conclusion, hypertensive patients had high level of electrodermal activity compared with normotensive subjects and this finding suggests that electrodermal activity which is explained excess tendency in Korean traditional medicine could be used for diagnosis in hypertension patients at Korean traditional medical clinic.

A Study on the Abdominal Diagnostic Method of Kitao Shunpo about the Movement Qi between kidneys (북미춘포(北尾春圃)의 신간동기(腎間動氣) 복진법(腹診法)에 대한 고찰(考察))

  • Kim, Hye-il;Baik, You-sang
    • Journal of Korean Medical classics
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    • v.29 no.3
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    • pp.113-132
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    • 2016
  • Objectives : In this study, the Abdominal Diagnostic Method of Kitao Shunpo(北尾春圃) about Movement Qi between kidneys in Sanghauidam(桑韓醫談) and Jeonggisinron(精氣神論) are investigated for the purpose of understanding the definite technique of the method and the position in the context of abdominal diagnosis in Japan. Methods : The materials related to the abdominal diagnosis to Movement Qi between kidneys were selected from Sanghauidam and Jeonggisinron written by Kitao Shunpo, and analyzed to know the characteristics of the method. Results : Kitao Shunpo suggested the theoretical background of the Abdominal Diagnostic Method that Original Qi(元氣) is made from Original Essence(元精) when a person is born, and mentality(神) and body essence(精), qi(氣) and blood(血) are formed from those. Movement Qi between kidneys(腎間動氣), that is to say innate Original Qi can be diagnosed in abdominal region by the method in Japanese Medicine. Kitao Shunpo decided deficiency and excess of Original Qi and prognosis in clinical treatment by the method, and suggested the standard pulse condition of the Movement Qi between kidneys. Conclusions : After the theory about Movement Qi between kidneys appeared in Nanjing(難經), many doctors have not made attention to diagnose that for a long time, until Kitao Shunpo with other Japanese doctors established the theoretical background of the Abdominal Diagnostic Method, and applied the theory to clinical treatment.

Four-pass dye laser amplifier for the direct pulsed amplification of a tunable narrow-bandwidth continuous-wave laser (좁은 선폭을 갖는 파장가변 연속파 레이저의 펄스형 증폭을 위한 사중경로 색소 레이저 증폭기)

  • 이재용;이해웅;유용심;한재원
    • Korean Journal of Optics and Photonics
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    • v.10 no.2
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    • pp.162-168
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    • 1999
  • A new design of four-pass dye laser amplifier affording a narrow-bandwidth pulsed output is demonstrated to suppress the amplified spontaneous emission(ASE) carried by the amplifier output and reduce the possibility of parasitic oscillation in the amplifier. By the direct pulsed amplification of a cw 100 mW dye laser under a Q-switched doubled Nd:YAG laser pumping with energy of 5.6 mJ/pulse, high-peak-power pulsed output with 1.5-mJ energy in 130-MHz bandwidth is obtained corresponding to a power gain greater than $2{\times}10^6$ and an energy efficiency of 27%. The ASE ratio in the four-pass amplifier output is dramatically reduced by using a diffraction grating in the amplifier. Compared with the results obtained from the normal operation of the amplifier with no frequency-selective device, the ASE ratio is reduced by a factor in excess of 10 to remain under 1.5% of the amplifier output whereas the total output energy is slightly increased by ~4%.

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A Bibliographic investigation in the method of Chong-Yol-Sa-Hwa(淸熱瀉火) on the treatment of Cerebro Vascular Attack (C.V.A.) (중풍치료(中風治法)에 있어서 청열사화법(淸熱瀉火法)에 대(對)한 문헌적(文獻的) 고찰(考察))

  • Park, Jung-Yang;Byun, Il
    • The Journal of Internal Korean Medicine
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    • v.12 no.1
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    • pp.155-165
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    • 1991
  • On the treatment of C.V.A, I obtain the results through the bibliographic investigation in the method of Chong-Yol-Sa-Hwa as follows ; 1. The method of Chong-Yol-Sa-Hwa on the treatment of CVA. is used for the occation of flaming fire in the heart caused by fire emotions in excess (五志過極), difficiency of Yin, flaming up of excessive in liver and plegm-heat. 2. The representative symptoms which can be used by the method of Chong-Yol-Sa-Hwa are firerishness, redness on face, foul breath, fidgets, angry, high fever, constipation slimy and greasy yellow coat of the tongue, and the pulse shaped on full-rapid (洪數), tautsmaooth and rapid (弦滑血數). 3. The general prescription on the method of Chong-Yol-Sa-Hwa are Bang pung tong sung-San, Yangkyuk-San, Backho-Tang, Sosiho-Tang, Samhwa-Tang, Chibo-Tan and Woohwang chongsim-Hwan on excessive symptom-complex, Yookmichihwang-Tang-Kakam, Samool-Tang-Kakam and Youngyangkak-Tang on insufficency symptom complex. 4. The most frequently dosed medicinal plants are Seok-ko, Chi-mo, Dae-Hwang, Mang-cho, Hwang-kewm, Hwang-back, Chi-ja, Si-ho, Han-Su-Seok, Yong-Tam-Cho, Mok-Tan-Pi and Saeng-Chi-Hwang. 5. The method of chong-Yol-Sa-Hwa might be expressed good medicinal effects adopted on the symptoms or flaming evil fire (火旺) after awakend and ‘Yang’ occlusion of Chung-Chang-Pu (中臟脈) which is accompanied with the method of purgation, break through the plegm, resuscitate and nourishing the Yin.

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An Observational Multi-Center Study Protocol for Distribution of Pattern Identification and Clinical Index in Parkinson's Disease (파킨슨병 변증 유형 및 지표 분포에 대한 전향적 다기관 관찰연구 프로토콜)

  • HuiYan Zhao;Ojin Kwon;Bok-Nam Seo;Seong-Uk Park;Horyong Yoo;Jung-Hee Jang
    • The Journal of Internal Korean Medicine
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    • v.45 no.1
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    • pp.1-10
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    • 2024
  • Objectives: This study investigated the pattern identification (PI) and clinical index of Parkinson's disease (PD) for personalized diagnosis and treatment. Methods: This prospective observational multi-center study recruited 100 patients diagnosed with PD from two Korean medicine hospitals. To cluster new subtypes of PD, items on a PI questionnaire (heat and cold, deficiency and excess, visceral PI) were evaluated along with pulse and tongue analysis. Gait analysis was performed and blood and feces molecular signature changes were assessed to explore biomarkers for new subtypes. In addition, unified PD rating scale II and III scores and the European quality of life 5-dimension questionnaire were assessed. Results: The clinical index obtained in this study analyzed the frequency statistics and hierarchical clustering analysis to classify new subtypes based on PI. Moreover, the biomarkers and current status of herbal medicine treatment were analyzed using the new subtypes. The results provide comprehensive data to investigate new subtypes and subtype-based biomarkers for the personalized diagnosis and treatment of PD patients. Ethical approval was obtained from the medical ethics committees of the two Korean medicine hospitals. All amendments to the research protocol were submitted and approved. Conclusions: An objective and standardized diagnostic tool is needed for the personalized treatment of PD by traditional Korean medicine. Therefore, we developed a clinical index as the basis for the PI clinical evaluation of PD. Trial Registration: This trial is registered with the Clinical Research Information Service (CRIS) (KCT0008677)