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Warpage of Co-fired High K/Low K LTCC Substrate (고유전율/저유전율 LTCC 동시소성 기판의 휨 현상)

  • Cho, Hyun-Min;Kim, Hyeong-Joon;Lee, Chung-Seok;Bang, Kyu-Seok;Kang, Nam-Kee
    • Journal of the Microelectronics and Packaging Society
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    • v.11 no.3
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    • pp.77-82
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    • 2004
  • In this paper, warpages of heterogeneous LTCC substrates comprised of high K/low K hi-layered structure were investigated. The effect of glass content in high K LTCC layer on the warpage of substrate during co-firing process was examined. Shrinkage and dielectric properties of high K and low K green sheets were measured. In-situ camber observation by hot stage microscopy showed different camber development of heterogeneous LTCC substrates according to glass content in high K green sheet. High K green sheet containing $50\%$ glass was matched to low K green sheet in the shrinkage. Therefore, LTCC substrate of Low K/High K+$50\%$ glass structure showed flat surface after sintering.

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Fabrication and Evaluation of AC 400 kV High Voltage Divider using Electric Field Sensor (전기장 센서를 이용한 교류 400 kV 고전압 분압기의 제작 및 평가)

  • Lee, Sang-Hwa;Han, Sang-Gil;Jung, Jae-Kap;Kang, Jeon-Hong;Kim, Yoon-Hyoung;Jeong, Jin-Hye;Han, Sang-Ok
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.57 no.3
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    • pp.265-269
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    • 2008
  • Output voltage value of AC high voltage source has usually been obtained by measuring the low arm voltage of high voltage divider or the secondary voltage of high voltage transformer. In this study, we have fabricated the AC 400 kV high voltage divider using high voltage electrode and electric field measurement sensor. The dividing ratio of the fabricated 400 kV high voltage divider was evaluated using reference 400 kV capacitive divider. The dividing ratio of 400 kV high voltage divider is found to be 12,322 and has the good linearity within 0.63 % against AC high voltage up to 400 kV. Therefore, the developed 400 kV high voltage divider could evaluate 400 kV high voltage supply and voltage divider used in industry.

Device and Circuit Performance Issues with Deeply Scaled High-K MOS Transistors

  • Rao, V. Ramgopal;Mohapatra, Nihar R.
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.4 no.1
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    • pp.52-62
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    • 2004
  • In this paper we look at the effect of Fringe-Enhanced-Barrier-lowering (FEBL) for high-K dielectric MOSFETs and the dependence of FEBL on various technological parameters (spacer dielectrics, overlap length, dielectric stack, S/D junction depth and dielectric thickness). We show that FEBL needs to be contained in order to maintain the performance advantage with scaled high-K dielectric MOSFETs. The degradation in high-K dielectric MOSFETs is also identified as due to the additional coupling between the drain-to-source that occurs through the gate insulator, when the gate dielectric constant is significantly higher than the silicon dielectric constant. The technology parameters required to minimize the coupling through the high-K dielectric are identified. It is also shown that gate dielectric stack with a low-K material as bottom layer (very thin $SiO_2$ or oxy-nitride) will be helpful in minimizing FEBL. The circuit performance issues with high-K MOS transistors are also analyzed in this paper. An optimum range of values for the dielectric constant has been identified from the delay and the energy dissipation point of view. The dependence of the optimum K for different technology generations has been discussed. Circuit models for the parasitic capacitances in high-K transistors, by incorporating the fringing effects, have been presented.

High $K^+$-Induced Relaxation by Nitric Oxide in Human Gastric Fundus

  • Kim, Dae-Hoon;Kim, Young-Chul;Choi, Woong;Yun, Hyo-Young;Sung, Ro-Hyun;Kim, Hun-Sik;Kim, Heon;Yoo, Ra-Young;Park, Seon-Mee;Yun, Sei-Jin;Song, Young-Jin;Xu, Wen-Xie;Lee, Sang-Jin
    • The Korean Journal of Physiology and Pharmacology
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    • v.16 no.5
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    • pp.297-303
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    • 2012
  • This study was designed to elucidate high $K^+$-induced relaxation in the human gastric fundus. Circular smooth muscle from the human gastric fundus greater curvature showed stretch-dependent high $K^+$ (50 mM)-induced contractions. However, longitudinal smooth muscle produced stretch-dependent high $K^+$-induced relaxation. We investigated several relaxation mechanisms to understand the reason for the discrepancy. Protein kinase inhibitors such as KT 5823 (1 ${\mu}M$) and KT 5720 (1 ${\mu}M$) which block protein kinases (PKG and PKA) had no effect on high $K^+$-induced relaxation. $K^+$ channel blockers except 4-aminopyridine (4-AP), a voltage-dependent $K^+$ channel ($K_V$) blocker, did not affect high $K^+$ -induced relaxation. However, N(G)-nitro-L-arginine and 1H-(1,2,4)oxadiazolo (4,3-A)quinoxalin-1-one, an inhibitors of soluble guanylate cyclase (sGC) and 4-AP inhibited relaxation and reversed relaxation to contraction. High $K^+$-induced relaxation of the human gastric fundus was observed only in the longitudinal muscles from the greater curvature. These data suggest that the longitudinal muscle of the human gastric fundus greater curvature produced high $K^+$-induced relaxation that was activated by the nitric oxide/sGC pathway through a $K_V$ channel-dependent mechanism.

Performance Analysis of Top-K High Utility Pattern Mining Methods (상위 K 하이 유틸리티 패턴 마이닝 기법 성능분석)

  • Ryang, Heungmo;Yun, Unil;Kim, Chulhong
    • Journal of Internet Computing and Services
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    • v.16 no.6
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    • pp.89-95
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    • 2015
  • Traditional frequent pattern mining discovers valid patterns with no smaller frequency than a user-defined minimum threshold from databases. In this framework, an enormous number of patterns may be extracted by a too low threshold, which makes result analysis difficult, and a too high one may generate no valid pattern. Setting an appropriate threshold is not an easy task since it requires the prior knowledge for its domain. Therefore, a pattern mining approach that is not based on the domain knowledge became needed due to inability of the framework to predict and control mining results precisely according to the given threshold. Top-k frequent pattern mining was proposed to solve the problem, and it mines top-k important patterns without any threshold setting. Through this method, users can find patterns from ones with the highest frequency to ones with the k-th highest frequency regardless of databases. In this paper, we provide knowledge both on frequent and top-k pattern mining. Although top-k frequent pattern mining extracts top-k significant patterns without the setting, it cannot consider both item quantities in transactions and relative importance of items in databases, and this is why the method cannot meet requirements of many real-world applications. That is, patterns with low frequency can be meaningful, and vice versa, in the applications. High utility pattern mining was proposed to reflect the characteristics of non-binary databases and requires a minimum threshold. Recently, top-k high utility pattern mining has been developed, through which users can mine the desired number of high utility patterns without the prior knowledge. In this paper, we analyze two algorithms related to top-k high utility pattern mining in detail. We also conduct various experiments for the algorithms on real datasets and study improvement point and development direction of top-k high utility pattern mining through performance analysis with respect to the experimental results.

Changes in the Nitrate Assimilation and Ascorbic Acid Content of Spinach Plants Treatmented with Nutrient Solutions Containing High Nitrogen and Low Potassium (고질소 및 저 칼륨 양액처리시 시금치내의 비타민C및 질소 대사의 변화)

  • Park, Yang-Ho;Seo, Beom-Seok
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.4
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    • pp.301-306
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    • 2009
  • This study was conducted to determine the physiological differences betweenhealthy and wilted plants with respect to nitrate assimilation and ascorbic acid content. Wilting was artificially induced in spinach plants by treating the seeds with nutrient solution containing high nitrogen and low potassium. The plants were cultured in different plots 4 types of media: 1N-1P-1K (control), 6N-1P-0K (0K), 6N-1P-0.5K (0.5K), and 6N-1P-2K (2K). The rate of wilting among the plants was as follows: control, 0%; 2K, 10%; 0.5K, 40%; and 0K, 70%. This shows that under high nitrogen conditions, the lower the amount of potassium provided, higher was the rate of wilting. There were no differences in plant growth among the plants treated with different levels of potassium under high nitrogen conditions.The nitrate content in both the leaves and the roots was higher in plants grown under high nitrogen media than those in the control. Furthermore, the nitrate level decreased with increasing potassium concentration. The ascorbic acid content of spinach under high nitrogen conditions was lower than those of the control.

Relationships between Parent-Adolescent Communication and Family Cohesion and Adaptability: Korean Adolescents Resident in Korea and in America (한국 청소년과 재미교포 청소년이 지각한 부모 자녀간 의사 소통과 가족 응집성 및 적응성간의 관계)

  • Kil, Ae Jin;Yi, Soon Hyung
    • Korean Journal of Child Studies
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    • v.20 no.1
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    • pp.239-248
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    • 1999
  • The purpose of this study was to examine relationships between parent-adolescent communication, family cohesion and family adaptability perceived by Korean adolescents resident in Korea (K-K) and Korean adolescents resident in America (K-A). Subjects were selected from among middle and high school, undergraduate and graduate school students in Korea (N=555) and counterpart students in Los Angeles (N=296). The survey instruments were the Parent-Adolescent Communication Inventory (Barnes & Olson, 1982) and FACES III (Bell, Olson, & Partner, 1982). Major findings were that : (1) K-A adolescents engaged in open communication with their parents more than K-K adolescents. (2) K-A families communicated about their health and life styles more frequently than K-K families, while K-K families communicated about school problems and problems with friends more than K-A families. (3) In both groups, family cohesion was related to family adaptability. That is, when family cohesion was high, family adaptability was also high. (4) When communication styles were open, perceived family cohesion and adaptability was high.

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Study of High-k Sensing Membranes for the High Quality Electrolyte Insulator Semiconductor pH Sensor (High-k 감지막 평가를 통한 고성능 고감도의 Electrolyte-Insulator-Semiconductor pH센서 제작)

  • Bae, Tae-Eon;Jang, Hyun-June;Cho, Won-Ju
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.25 no.2
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    • pp.125-128
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    • 2012
  • We fabricated the electrolyte-insulator-semiconductor (EIS) devices with various high-k sensing membranes to realize a high quality pH sensor. The sensing properties of each high-k dielectric material were compared with those of conventional $SiO_2$ (O) and $SiO_2/Si_3N_4$ (ON) membranes. As a result, the high-k sensing membranes demonstrated better sensitivity and stability than the O and ON membranes. Especially, the $SiO_2/HfO_2$ (OH) stacked layer showed a high sensitivity and the $SiO_2/Al_2O_3$ (OA) stacked layer exhibited an excellent chemical stability. In conclusion, the high-k sensing membranes are expected to have excellent operating characteristics in terms of sensitivity and chemical stability for the biosensor application.

Pulse energy high Power test of metal film resistor (메탈 필름 저항의 펄스 대전력 시험)

  • Son, Y.G.;Jang, S.D.;Kwon, S.J.;Oh, J.S.;Cho, M.H.;Lee, K.T.
    • Proceedings of the KIEE Conference
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    • pp.2103-2105
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    • 2005
  • Metal film type of resistor have been tested to invest maximum usable power at the pulsed high voltage and pulsed high current. Experiments were carried out using capacitor charging power supply and dump switch. Pulsed amplitude were varied from 1kV to 25kV. The peak current reached was 1kA. Datasheet are given for the limited pulsed power and energy for metal film type of resistor in nanosecond and microsecond time range. The experimental investigation of the threshold loading of the resistor in the high current and voltage pulsed mode has shown that the process of destruction of resistor has specific features for each mode. The mechanisms of failure and destruction of resistors under action of high-voltage and high-current pulses are discussed.

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Short- and Long-term Effects of Potassium on Renin-Aldosterone System in Hypertensive Rats Fed with Different Amounts of Sodium

  • Kim, Sook-Young;Yang, Eun-Kyung;Park, Jae-Sik;Lee, Won-Jung;Kim, Suhn-Hee
    • The Korean journal of physiology & pharmacology
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    • v.25 no.1
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    • pp.69-79
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    • 1991
  • To evaluate the acute and chronic effects of potassium on aldosterone response to different amounts of sodium intake, two series of experiments were conducted. In the first series of experiments, when the plasma K level was increased acutely by KCI infusion $(20\;{\mu}g/kg/min\;for\;20 min)$, plasma aldosterone concentration increased in both low Na and high Na groups. However, the aldosterone response to K infusion was significantly greater in the low Na than in the high Na groups. In the second series of experiments, rats fed a high K diet chronically showed a significantly higher plasma K level than those fed a low K diet. However, plasma Na level was maintained relatively constant independent of the Na intake. Both the plasma renin activity (PRA) and aldosterone levels were inversely related to the Na intake. There was a highly positive correlation between aldosterone level and PRA over a wide range of sodium intakes. However, the slope of the correlation line was distinctly steeper in the K-repleted than in the K-depleted rats. The above results indicate that the adrenotropic action of acute K load was augmented in the presence of high plasma renin levels. However, when plasna K level was elevated chronically by a high-K diet, aldosterone secretion was markedly stimulated, although the plasma lenin levels were suppressed.

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