자동차용 실리콘 가속도센서의 개발(Ⅱ)

이종현,신장규,이상룡,천희곤,조찬섭,심준환,류인식,박석홍,허정준,박기열 경북대학교 센서기술연구소 1994 연차보고서 Vol.1994 No.-

자동차의 air-bag 장치에 실용될 수 있는 압저항형 단결정 실리콘 가속도센서 칩을 개발하기 위하여 결정 실리콘 미세구조의 제조방법을 확립하고, 단위공정의 검증을 통하여 일괄공정에 의한 PROTO-TYPE 칩을 만드는 기술을 연구하였다. 단결정 실리콘 미세구조는 선택확산법을 이용하여 정확히 선택된 영역에만 air-gap을 형성하여 미세구조의 측면식각을 방지하는 선택확산법에 의한 실리콘 마이크로머시닝 기술로 제조하였다. 일괄공정을 위한 단위공정확립을 위하여 PROTY-TYPE 8빔 브릿지형 가속도 센서를 제조하였다. 제조된 칩의 가속도에 따른 출력전압은 선형성을 나타내고 있으며, 감도는 약 50 ㎶/V·g로 나타났다. 이 감도는 50G용 가속도센서의 사양을 만족하지 못했다. 이는 공정에 의한 문제라기 보다는 가속도센서의 시뮬레이션에 의해 설계한 구조가 이미 원하는 감도에 못 미친다는 것으로 생각된다. 따라서 2차 공정으로 제조될 가속도센서의 파라미터를 SuperSAP 유한요소 패키지를 이용하여 실리콘 미세구조부의 파라미터에 따른 특성을 시뮬레이션하였다. 설계된 50G용 가속도센서의 mass Pad의 반경 및 빔 길이, 빔 폭, 빔 두께, 그리고 mass의 각 파라미터 값은 700 ㎛, 120 ㎛, 5 ㎛, 1.0 ㎎ 이었다. 반도체 공정기술, 관성질량 제조법 및 선택확산을 이용한 마이크로머시닝을 사용하여 일괄공정으로 8빔 브린지형 가속도센서를 제조하였다. We researched the establishment of the silicon microstructure fabrication technique to develop a piezoresistive type silicon acceleration sensor chip and the technique to make a proto-type chip by the verification of the unit-process. Silicon microstructure is fabricated silicon micro-machining by selective diffusion method. This method prevent a side-etching of microstructure because selective diffused region is only formed an air-gap. We fabricated a proto-type 8-beam bridge-type acceleration sensor to establish the unit-process for the batch-process. The output voltage of the chip represented linearity with acceleration, and the sensitivity was about 50 ㎶/V·g. But this sensitivity dosen't satisfy the requirements of a practical acceleration sensor. The cause of this result is assumed not process problem, but the structure designed by simulation isn't suitable already. Threfore, the characteristics of parameters of the acceleration sensor that will be fabricated by 2nd-process is simulated by SuperSAP finite-element package. The determined parameter values of beam length, beam width, beam thickness, mass, and mass radius are 120 ㎛, 5 ㎛, 1.0 ㎎, and 700 ㎛, respectively. We fabricated 8-beam bridge-type acceleration sensor by batch-process using a semiconductor process technique, proof-mass fabrication method, and micromachinig using selective diffusion.

지방정부 민원행정서비스 평가의 의의와 측정모형

서휘석,이동기 全北行政學會 2003 全北行政學報 Vol.17 No.1

고객지향적인 개념의 행정 접근은 이제 중요한 항목으로 받아들이고 있다. 특히 지방자치제가 도입된 이후 그 정도나 내용은 더욱 크게 주목받고 있다. 그 중 민원서비스 부문에 대한 관심은 지방정부의 민원프로그램의 개발과 운영, 서비스 접목 등에 집중되고 있다. 이러한 현상은 지방정부의 근본적인 형태가 지역주민에 바탕을 두고 있으며 이를 통하여 행정의 변화를 이끌어 내기 위한 노력을 하고 있다는 것을 확인할 수 있다. 민원행정서비스의 질과 그 제공 절차에 대한 시민의 인식은 정책의 지속성 유지뿐만 아니라 수혜자인 시민의 삶의 질에 결정적인 영향을 미친다고 보았을 때 그 중요성은 더욱 크다고 볼 수 있다. 따라서 본 연구는 지방정부의 민원행정서비스에 대한 평가의 의의와 측정모형에 대한 초점을 둔다. 민원행정서비스에 대한 평가모델은 시민들과의 직접적인 관계를 형성할 뿐만 아니라 행정의 변화를 느끼게 하는 중요한 창구이고 의사소통의 채널이기 때문이다.

한국 학생들의 영어 어두자음 발화학습에 관한 실험 연구

강석근,이희천 서울대학교 어학연구소 2002 語學硏究 Vol.38 No.1

The purpose of this paper is to examine through experiment if Korean students can learn sounds like /r/, /f/, /b/ and /v/ precisely, sounds which Korean does not contain, and to discover methods whereby this learning may be accomplished. To this end, we prepared two kinds of test materials with 30 questions each, consisting of pairs with /l, r/, /f, p/, and /b, v/ in word-initial positions. In the tests, 40 third-year students from Janghang Technical High School served as subjects. The subjects were divided into two groups: an experimental group and a control group. The tests consisted of two steps. First, we examined each group's pronunciation ability of the above consonants in word-initial positions. Next, after teaching the experimental group the differences between the consonants above with special programs, we examined their degree of improvement. The results showed that the pronunciation ability of the experimental group improved more than that of the control group. In conclusion, although most of the subjects of the control group had difficulty in pronouncing the sounds that Korean does not contain, they improved their pronunciation ability to some degree by learning the place and manner of articulation, and through reetitive practice.

The benzodiazepine anesthetic midazolam prevents hyperglycemia‐induced microvascular leakage in the retinas of diabetic mice

Lee, Yeon-Ju,Kim, Minsoo,Lee, Jee-Yeon,Jung, Se-Hui,Jeon, Hye-Yoon,Lee, Seung Ah,Kang, Seongsik,Han, Eun-Taek,Park, Won Sun,Hong, Seok-Ho,Kim, Young-Myeong,Ha, Kwon-Soo Federation of American Society for Experimental Bi 2018 The FASEB Journal Vol.32 No.11

Identification of a novel mutation in a patient with pseudohypoparathyroidism type Ia

Lee, Ye Seung,Kim, Hui Kwon,Kim, Hye Rim,Lee, Jong Yoon,Choi, Joong Wan,Bae, Eun Ju,Oh, Phil Soo,Park, Won Il,Ki, Chang Seok,Lee, Hong Jin The Korean Pediatric Society 2014 Clinical and Experimental Pediatrics (CEP) Vol.57 No.5

Pseudohypoparathyroidism type Ia (PHP Ia) is a disorder characterized by multiform hormonal resistance including parathyroid hormone (PTH) resistance and Albright hereditary osteodystrophy (AHO). It is caused by heterozygous inactivating mutations within the Gs alpha-encoding GNAS exons. A 9-year-old boy presented with clinical and laboratory abnormalities including hypocalcemia, hyperphosphatemia, PTH resistance, multihormone resistance and AHO (round face, short stature, obesity, brachydactyly and osteoma cutis) which were typical of PHP Ia. He had a history of repeated convulsive episodes that started from the age of 2 months. A cranial computed tomography scan showed bilateral calcifications in the basal ganglia and his intelligence quotient testing indicated mild mental retardation. Family history revealed that the patient's maternal relatives, including his grandmother and 2 of his mother's siblings, had features suggestive of AHO. Sequencing of the GNAS gene of the patient identified a heterozygous nonsense mutation within exon 11 (c.637 C>T). The C>T transversion results in an amino acid substitution from Gln to stop codon at codon 213 ($p.Gln213^*$). To our knowledge, this is a novel mutation in GNAS.

Metagenome analysis: organic fruit thinner has impact on microbial community of Ginkgo biloba rhizosphere

Seok Hui Lee,Jong-Beom Seo,Jun Young Park,Ah Hyeon Choi,Dae Sol Kim,Do Yeon Kim,Su Hong Jeon,Hee Min Lim,Woo Jin Park,Sin Young Park,Sang Jun Park,Seong-Ho Kim,Jae Doo Jo,Jun Won Kang 충남대학교 농업과학연구소 2023 Korean Journal of Agricultural Science Vol.50 No.1

InsP₆-Sensitive Variants of the Gle1 mRNA Export Factor Rescue Growth and Fertility Defects of the <i>ipk1</i> Low-Phytic-Acid Mutation in Arabidopsis

Lee, Ho-Seok,Lee, Du-Hwa,Cho, Hui Kyung,Kim, Song Hee,Auh, Joong Hyuck,Pai, Hyun-Sook American Society of Plant Biologists 2015 The Plant cell Vol.27 No.2

<P>Expression of Gle1 variants with modified InsP<SUB>6</SUB> binding pockets rescues mRNA export defects of the <I>ipk1</I> InsP<SUB>6</SUB>-deficient mutant, suggesting a critical role for Gle1 in mediating InsP<SUB>6</SUB> function.</P><P><I>Myo</I>-inositol-1,2,3,4,5,6-hexa<I>kis</I>phosphate (InsP<SUB>6</SUB>), also known as phytic acid, accumulates in large quantities in plant seeds, serving as a phosphorus reservoir, but is an animal antinutrient and an important source of water pollution. Here, we report that Gle1 (GLFG lethal 1) in conjunction with InsP<SUB>6</SUB> functions as an activator of the ATPase/RNA helicase LOS4 (low expression of osmotically responsive genes 4), which is involved in mRNA export in plants, supporting the Gle1-InsP<SUB>6</SUB>-Dbp5 (LOS4 homolog) paradigm proposed in yeast. Interestingly, plant Gle1 proteins have modifications in several key residues of the InsP<SUB>6</SUB> binding pocket, which reduce the basicity of the surface charge. <I>Arabidopsis thaliana</I> Gle1 variants containing mutations that increase the basic charge of the InsP<SUB>6</SUB> binding surface show increased sensitivity to InsP<SUB>6</SUB> concentrations for the stimulation of LOS4 ATPase activity in vitro. Expression of the Gle1 variants with enhanced InsP<SUB>6</SUB> sensitivity rescues the mRNA export defect of the <I>ipk1</I> (<I>inositol 1,3,4,5,6-penta</I>kis<I>phosphate 2-kinase</I>) InsP<SUB>6</SUB>-deficient mutant and, furthermore, significantly improves vegetative growth, seed yield, and seed performance of the mutant. These results suggest that Gle1 is an important factor responsible for mediating InsP<SUB>6</SUB> functions in plant growth and reproduction and that Gle1 variants with increased InsP<SUB>6</SUB> sensitivity may be useful for engineering high-yielding low-phytate crops.</P>

A New Record of the Varunid Crab, Varuna yui (Decapoda: Varunidae), from Korea

Lee, Sang-Hui,Jeong, Jin-Hyeop,Kim, Ju-Yeon,Lee, Seok-Hyun The Korean Society of Systematic Zoology 2022 Animal Systematics, Evolution and Diversity Vol.38 No.1

The varunid crab, Varuna yui Hwang & Takeda, 1986, is known as widely distributed in the Southeast Asian region. Three specimens of varunid crabs were collected near the estuary of the river from Korea and identified as V. yui. Varuna yui could be distinguished from the other congeneric species, V. litterata (Fabricius, 1798), by having a more extended mesial lobe on the distal region of the male first gonopod. In this paper, morphological diagnosis and illustrations of the newly collected V. yui are provided. The specimens examined herein were deposited in the National Marine Biodiversity Institute of Korea and Nakdonggang National Institute of Biological Resources.

Cryptosporidium Infection in Animal Facilities in Korea

Hui-Young Lee,Seung-Hyeok Seok,Min-Won Baek,Dong-Jae Kim,Byoung-Hee Lee,Jae-Hak Park 한국실험동물학회 2005 Laboratory Animal Research Vol.21 No.4

We investigated the presence of Cryptosporidium in four specific pathogen free (SPF) and four conventional facilities in Korea. From November 2000 to March 2005, 329 mice were histopathologically examined for Cryptosporidium infection, and infection was detected in 18.52% (5 of 27) and 3.68% (7 of 190) animals in 2000 and 2004, respectively. The detected Cryptosporidium was classified based on oocyst size and the parasitized organ. Oocysts were predominantly round to oval (measured by light microscopy, 5~12×5~10 ㎛) and parasitized the stomach. To confirm Cryptosporidium infection, PCR was performed to detect genes of Cryptosporidium parvum and Cryptosporidium oocyst wall protein. Our results suggest that Cryptosporidium had infected conventional mice, but that it had not infected SPF mice in Korea. The detected Cryptosporidium was presumed to be C. muris based on oocyst size and parasitized organ.

Evaluation of<i>phoP</i>and<i>rpoS</i>mutants of<i>Salmonella enterica</i>serovar Typhi as attenuated typhoid vaccine candidates: virulence and protective immune responses in intranasally immunized mice

Lee, Hui-Young,Cho, Sun-A,Lee, In-Soo,Park, Jong-Hwan,Seok, Seung-Hyeok,Baek, Min-Won,Kim, Dong-Jae,Lee, Seok-Ho,Hur, Sook-Jin,Ban, Sang-Ja,Lee, Yoo-Kyoung,Han, Yang-Keum,Cho, Young-Keun,Park, Jae-Hak Oxford University Press 2007 FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY Vol.51 No.2

<P>The attenuation and immunoenhancing effects of rpoS and phoPSalmonella enterica serovar strain Typhi (Salmonella typhi) mutants have not been compared. Here, three S. typhi deletion mutants (phoP, rpoS, and rpoS-phoP double mutant) are constructed and these mutants are characterized with respect to invasiveness, virulence, and protective immune response compared with wild-type Ty2. It was found that phoP and phoP-rpoS deletion mutants are less invasive to HT-29 cells than the wild-type Ty2 and the rpoS single-deleted strain. The LD(50) of immunized mice was higher for phoP than for rpoS mutants, and the highest for the phoP-rpoS double mutant. In addition, all S. typhi mutants showed an increase in the specific serum IgG levels and T-cell-mediated immunity, and showed equal protection abilities against a wild-type Ty2 challenge after two rounds of immunization in BALB/c mice. It is concluded that phoP genes appear to play a more important role than rpoS genes in both cellular invasion and virulence of S. typhi, but not in immunogenicity in mice. Furthermore, the data indicate that the phoP-rpoS double mutant may show promise as a candidate for an attenuated typhoid vaccine.</P>