• 제목/요약/키워드: Double Well Function

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Packaging MEMS, The Great Challenge of the $21^{st}$ Century

  • Bauer, Charles-E.
    • 한국마이크로전자및패키징학회:학술대회논문집
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    • 한국마이크로전자및패키징학회 2000년도 Proceedings of 5th International Joint Symposium on Microeletronics and Packaging
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    • pp.29-33
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    • 2000
  • MEMS, Micro Electro-Mechanical Systems, present one of the greatest advanced packaging challenges of the next decade. Historically hybrid technology, generally thick film, provided sensors and actuators while integrated circuit technologies provided the microelectronics for interpretation and control of the sensor input and actuator output. Brought together in MEMS these technical fields create new opportunities for miniaturization and performance. Integrated circuit processing technologies combined with hybrid design systems yield innovative sensors and actuators for a variety of applications from single crystal silicon wafers. MEMS packages, far more simple in principle than today's electronic packages, provide only physical protection to the devices they house. However, they cannot interfere with the function of the devices and often must actually facilitate the performance of the device. For example, a pressure transducer may need to be open to atmospheric pressure on one side of the detector yet protected from contamination and blockage. Similarly, an optical device requires protection from contamination without optical attenuation or distortion being introduced. Despite impediments such as package standardization and complexity, MEMS markets expect to double by 2003 to more than $9 billion, largely driven by micro-fluidic applications in the medical arena. Like the semiconductor industry before it. MEMS present many diverse demands on the advanced packaging engineering community. With focused effort, particularly on standards and packaging process efficiency. MEMS may offer the greatest opportunity for technical advancement as well as profitability in advanced packaging in the first decade of the 21st century! This paper explores MEMS packaging opportunities and reviews specific technical challenges to be met.

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보조 반사체를 이용한 광섬유 페브리페로 간섭계형 온도센서의 성능향상 (Unambiguous Fiber Fabry-Perot Temperature Sensor by an Additional Partial Mirror)

  • 김광수;이홍식
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제49권7호
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    • pp.418-423
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    • 2000
  • The fiber Fabry-Perot interferometric(FFPI) sensor is well known in the field of industrial diagnosis due to its outstanding properties such as tiny size, simple and rugged structure, and easy interrogation. As other fiber interferometric sensors, it also suffers from ambiguous output caused by highly periodic feature in its optical transfer function. In most cases, the ambiguity leads to relatively short dynamic operating range and long processing time during power-on reset, which limits its application to some specific fields requiring very high resolution. In this paper a method based on double sensing scheme was proposed to overcome the above difficulty. By employing a fringe selection auxiliary FFPI sensor the original FFPI sensor can identify its true position on the phase domain. The performance test with 10mm FFPI sensor and a thermocouple temperature sensor for reference shows wide dynamic range 0-900$\ell$ keeping a reasonable resolution of 0.1$\ell$ over the entire range.

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3D Structure of Bacillus halodurans O-Methyltransferase, a Novel Bacterial O-Methyltransferase by Comparative Homology Modeling

  • Lee, Jee-Young;Lee, Sung-Ah;Kim, Yang-Mee
    • Bulletin of the Korean Chemical Society
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    • 제28권6호
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    • pp.941-946
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    • 2007
  • Bacillus halodurans O-methyltransferase (BhOMT) is a S-adenosylmethionine (SAM or AdoMet) dependent methyltransferase. Three dimensional structure of the BhOMT bound to S-adenosyl-L-homocysteine (SAH or AdoHcy) has been determined by comparative homology modeling. BhOMT has 40% sequence identity with caffeoyl-CoA 3-O-methyltransferase (CCoAOMT) from alfalfa. Based on x-ray structure of CCoAOMT, three dimensional structure of BhOMT was determined using MODELLER. The substrate binding sites of these two proteins showed slight differences, but these differences were important to characterize the substrate of BhOMT. Automated docking study showed that four flavonoids, quercetin, fisetin, myricetin, and luteolin which have two hydroxyl groups simultaneously at 3'- and 4'-position in the B-ring and structural rigidity of Cring resulting from the double bond characters between C2 and C3, were well docked as ligands of BhOMT. These flavonoids form stable hydrogen bondings with K211, R170, and hydroxyl group at 3'-position in the Bring has stable electrostatic interaction with Ca2+ ion in BhOMT. This study will be helpful to understand the biochemical function of BhOMT as an O-methyltransferase for flavonoids.

The G115 standardized ginseng extract: an example for safety, efficacy, and quality of an herbal medicine

  • Bilia, Anna R.;Bergonzi, Maria C.
    • Journal of Ginseng Research
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    • 제44권2호
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    • pp.179-193
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    • 2020
  • Ginseng products on the market show high variability in their composition and overall quality. This becomes a challenge for both consumers and health-care professionals who are in search of high-quality, reliable ginseng products that have a proven safety and efficacy profile. The botanical extract standardization is of crucial importance in this context as it determines the reproducibility of the quality of the product that is essential for the evaluation of effectiveness and safety. This review focuses on the well-characterized and standardized ginseng extract, G115, which represents an excellent example of an herbal drug preparation with constant safety and efficacy within the herbal medicinal products. Over the many decades, extensive preclinical and clinical research has been conducted to evaluate the efficacy and safety of G115. In vitro and in vivo studies of G115 have shown pharmacological effects on physical performance, cognitive function, metabolism, and the immune system. Furthermore, a significant number of G115 clinical studies, most of them double-blind placebo-controlled, have reinforced the findings of preclinical evidence and proved the efficacy of this extract on blood glucose and lipid regulation, chronic obstructive pulmonary disease, energy, physical performance, and immune and cognitive functions. Clinical trials and 50 years of presence on the market are proof of a good safety profile of G115.

The Relationship between Tree-Ring Growth in Pinus densiflora S. et Z. and the Corresponding Climatic Factors in Korea

  • LEE, Kwang Hee;JO, Sang Yoon;KIM, Soo Chul
    • Journal of the Korean Wood Science and Technology
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    • 제50권2호
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    • pp.81-92
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    • 2022
  • To analyze the relationship between climatic factors (mean monthly temperature and total precipitation) and tree-ring growths of Pinus densiflora S. et Z. from National Parks (according to region) of the Korea, 20 trees were sampled from 13 National Parks. Only trees that were successfully cross-dated were used for dendrochronological analysis, and at least 11 trees were included. The tree-ring chronology of Mt. Bukhan (covering the shortest period of 1917 - 2016 [100 years]) was assessed, as well as that of Mt. Seorak (covering the longest period of 1687 - 2017 [331 years]). After cross-dating, each ring width series was double-standardized by first fitting a logarithmic curve and then a 50-year cubic spline. The relationships between climate and tree-ring growth were calculated with response function analysis. The results show a significant positive correlation between a given year's February-March temperature, May precipitation levels, and tree-ring growth. It indicates that a higher temperature in early spring and precipitation before cambium activity are important for radial growths of Pinus densiflora in the Korea.

Effects of AIF on Knee Osteoarthritis Patients: Double-blind, Randomized Placebo-controlled Study

  • Park, Sung-Hoon;Kim, Seong-Kyu;Shin, Im-Hee;Kim, Hyung-Gun;Choe, Jung-Yoon
    • The Korean Journal of Physiology and Pharmacology
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    • 제13권1호
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    • pp.33-37
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    • 2009
  • Anti-inflammatory factor(AIF) is a water soluble extract of three herbs, Panax notoginseng(Burk.) F. H. Chen, Rehmannia glutinosa Libosch and Eleutherococcus senticosus. The present study aimed to investigate the safety and efficacy of herb extracts, AIF, on Korean knee osteoarthritis patients for six weeks. Fifty seven patients with knee osteoarthritis, ranging from 43 to 73 years of age, who fulfilled the "American College of Rheumatology"(ACR) classification of idiopathic osteoarthritis of knee and radiographic criteria were randomly selected and enrolled for the study. After initial screening and resting period, two capsules each of AIF(Each capsule contains; 400 mg) and similar identical placebo were administered twice a day to both groups. Pain intensity at second, fourth, and sixth weeks of study as well as one week after discontinuation of drugs was assessed by using 100 mm visual analogue scale(VAS). Changes in the Korean version of the Western Ontario and McMaster Universities(K-WOMAC) index score were compared at the initiation and completion of the study. VAS assessed by patients were significantly reduced(at visit 2; $54.64{\pm}14.72$, at visit 4, $37.32{\pm}16.58$, p<0.001) after AIF administration. Results showed an improvement in the physical function of K-WOMAC scale which was significantly higher(p=0.013) in AIF than placebo group, and decreases of total K-WOMAC score were also significantly higher(p=0.030) in AIF groups than placebo group. No serious adverse effect was observed, and there was no difference in incidence of adverse effect between AIF and placebo groups. In this population of Korean patients with knee osteoarthritis, AIF was found to be safe, tolerable and effective for symptomatic improvement of pain and physical function.

Purification and Characterization of Hrp1, a Homolog of Mouse CHD1 from the Fission Yeast Schizosaccharomyces pombe

  • Yong Hwan Jin;Eung Jae Yoo;Yeun Kyu Jang;Seung Hae Kim;Chee-Gun Lee;Rho Hyun Seong;Seung Hwan Hong;Sang Dai Park
    • Animal cells and systems
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    • 제2권4호
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    • pp.539-543
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    • 1998
  • Hrp1, of Schizosaccharomyces pombe, is a new member of the SW12/SNF2 protein family that contains a chromodomain and a DNA binding domain as well as ATPase/7 helicase domains. This configuration suggests that Hrp1 could be a homolog of mouse CHD1, which is thought to function in altering the chromatin structure to facilitate gene expression. To understand the enzymatic nature of Hrp1 we purified the 6-Histidine-tagged Hrp1 protein (6$\times$His-Hrp1) to homogeneity from a S. pombe Hrp1-overexpressing strain and hen examined its biochemical properties. We demonstrate that the purified 6$\times$His-Hrp1 protein exhibited a DNA-binding activity with a moderate preference to the (A+T)-rich tract in double-stranded NA via a minor groove interaction. However, we failed to detect any intrinsic DNA helicase activity from the purified Hrp1 like other SW12/SNF2 proteins. These observations suggest that the DNA binding activities of Hrp1 may be involved in the remodeling of the chromatin structure with DNA-dependent ATPase. We propose that Hrp1 may function in heterochromatins as other proteins with a chromo- or ATPase/helicase domain and play an important role in the determination of chromatin architecture.

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Different Types of Active Region EUV Bright Points by Hinode/EIS

  • 이경선;문용재;김수진
    • 천문학회보
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    • 제35권1호
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    • pp.28.2-28.2
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    • 2010
  • We have investigated seven Extreme-Ultraviolet (EUV) bright points in the active region (AR 10926) on 2006 December 2 by the EUV imaging spectrometer (EIS) onboard Hinode spacecraft. We determined their Doppler velocities and non-thermal velocities from 15 EUV spectral lines (log T=4.7-7.2) by fitting each line profile to a Gaussian function. We present the Doppler velocity map as a function of temperature which corresponds to a different height. As a result, these active region bright points show two different types of characteristics. Type 1 bright point shows a systematic increase of Doppler velocity from -68 km/s (blue shift) at log T=4.7 to 27 km/s (red shift) at log T=6.7, while type 2 bright points have Doppler velocities in the range of -20 km/s and 20 km/s. Using MDI magnetograms, we found that only type 1 bright point was associated with the canceling magnetic feature at the rate of $2.4{\times}10^{18}$ Mx/hour. When assuming that these bright points are caused by magnetic reconnection and the Doppler shift indicates reconnection out flow, the pattern of the Doppler shift implies that type 1 bright point should be related to low atmosphere magnetic reconnection. We also determined electron densities from line ratio as well as temperatures from emission measure loci using CHIANTI atomic database. The electron densities of all bright points are comparable to typical values of active regions (log Ne=9.9-10.4). For the temperature analysis, the emission loci plots indicate that these bright points should not be isothermal though background is isothermal. The DEM analysis also show that while the background has a single peak distribution (isothermal), the EUV bright points, double peak distributions.

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Reduction-Sensitive and Cysteine Residue-Mediated Streptococcus pneumoniae HrcA Oligomerization In Vitro

  • Kwon, Hyog-Young;Kim, Eun-Hye;Tran, Thao Dang Hien;Pyo, Suhk-Neung;Rhee, Dong-Kwon
    • Molecules and Cells
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    • 제27권2호
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    • pp.149-157
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    • 2009
  • In both gram-positive and several gram-negative bacteria, the transcription of dnaK and groE operons is negatively regulated by HrcA; however, the mechanism modulating HrcA protein activity upon thermal stress remains elusive. Here, we demonstrate that HrcA is modulated via reduction and oligomerization in vitro. Native-PAGE analysis was used to reveal the oligomeric structure of HrcA. The oligomeric HrcA structure became monomeric following treatment with the reducing agent dithothreitol, and this process was reversed by treatment with hydrogen peroxide. Moreover, the mutant HrcA C118S exhibited reduced binding to CIRCE elements and became less oligomerized, suggesting that cysteine residue 118 is important for CIRCE element binding as well as oligomerization. Conversely, HrcA mutant C280S exhibited increased oligomerization. An HrcA double mutant (C118S, C280S) was monomeric and exhibited a level of oligomerization and CIRCE binding similar to wild type HrcA, suggesting that cysteine residues 118 and 280 may function as checks to one another during oligomer formation. Biochemical fractionation of E. coli cells overexpressing HrcA revealed the presence of HrcA in the membrane fraction. Together, these results suggest that the two HrcA cysteine residues at positions 118 and 280 function as reduction sensors in the membrane and mediate oligomerization upon stress.

무대 진입로에서 시민 참여와 소통으로 -고대 그리스 파로도스 공간의 기능과 의미에 대한 재고- (Passageway to Stage and for Civic Unification: Reconsideration of the Function of Parodos in Ancient Greek Theatre)

  • 박정만
    • 한국연극학
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    • 제48호
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    • pp.485-507
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    • 2012
  • Parodos, the side entrances to orchestra (acting space), was one of the intrinsic elements for the ancient Greek theatre structure. It is worth noting that parodos was the sole structural component that remained the original form while all the other elements such as orchestra, skene, and theatron experienced drastic or gradual changes in form throughout the passage of time. On the reason for parodo's maintenance of the original form, this study suggests a possibility that parodos could be the most intrinsic among the elements for Greek theatre buildings. For evidence, this paper indicates the historical fact that the procession tradition was the key event in the national or civic festival known as City Dionysia, and that the single-direction passageway, as seen in the Panathenaic Way passing through the City Athens, could be the easiest and most efficient way to realize the cause for the procession tradition that is the citizens' participation and subsequent unification. This study suggests another possibility that the single-direction passageway in the procession could be the archetype of parodos. For evidence, this study finds that this type of passageway was ubiquitous around the City Athens especially in the Agora, the most popular place in the city and the gateway to the processional event for Dionysian Cult as well as the space for the earliest Greek theatricality and, therefore, was familiar to the citizens. From the discussion, this paper argues that the Greek theatre should be the miniature of the Agora in terms of form (single-direction passageway) and function (civic participation and unification), and that parodos was the theatrical version of the processional passageway in the Dionysian Cult. In conclusion, this paper argues that parodos played a double role. It satisfied the theatrical necessity by functioning as the passageway to dramatic action (entrance and exit of actor/chorus) and as the literal door for the entrance of the audience members. At the same time, it satisfied the social cause, that is civic participation and subsequent unification, by functioning as the processional passage to relay the theatre space to civic events for the national religious cult.