• 제목/요약/키워드: C-MAC

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A Design and Implementation of ZigBee Educational System in USN Environment (USN환경에서 교육용 ZigBee 장비의 설계 및 구현)

  • Park, Gyun Deuk;Chung, Joong Soo;Jung, Kwang Wook
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.5
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    • pp.335-340
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    • 2013
  • This paper has designed and realized educational ZigBee equipment befitting to the USN environment. In addition, this study has enabled users to exercise operation process for software technology education and to propose software design methods in the process in the USN environment through practice equipment for ZigBee education. As for the development environment of system, Atmega128 process of Atmel is used for CPU; AVR compiler for the debugging environment; C language for firmware development language; and C++ for application program. The system operation process is initiated by coordinator's sensing information reading order from the hyper terminal through a server through the Internet or directly connected; and then delivering it to a terminating device by using ZigBee technology. The terminating device delivers various sensing information to the coordinator which delivers it to a server through the Internet or to a HYPER terminal directly connected to the coordinator. As for the educational course, it is about practices on such ZigBee operation process and relevant programing skills. Regarding it, the communication between coordinator and terminating device is designed by utilizing physical layer of ZigBee protocol, MAC layer and network layer while the communication between server and coordinator is designed by proposing an independent protocol on TCP/IP socket and the protocol processing procedure during sensing data delivery is verified by interpretation.

A Study of the Viscosity of Some Electrolytic Solutions and Its Concentration Function (電解質溶液의 粘度係數의 測定과 濃度關係에 對한 考察)

  • Sakong, Yull;Hwang, Jung-Eui
    • Journal of the Korean Chemical Society
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    • v.8 no.1
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    • pp.9-14
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    • 1964
  • The viscosities of strong electrolytic solutions, such as KCl, KI and NaI have been measured over a fairy wide range of concentration variation (from 0.00002 to 3.7M). It was hoped that a study of the data in the light of modern theories on solution might reveal new relation between viscosity and surface tension of electrolytic solution. To secure more accurate measurements of viscosity and surface tension of the solutions, Ostwald viscometer was made with pyrex glass and modified the timing system for the transit of the meniscus with a new electronics system and with a pulse counter. As the experimental data obtained were in good agreement with the Jone's values, Jones-Dole equations for the electrolytic solutions were deduced, ${\eta}KCl\;=\;1\;+\;0.0052{\sqrt{c}}\;-\;0.01612c\;+\;0.00808c^2\;at\;30^{\circ}C$ ${\eta}KI\;=\;1\;+\;0.0220{\sqrt{c}}\;-\;0.01290c\;+\;0.02988c^2\;at\;25^{\circ}C$${\eta}Na\; =\;1\;+\;0.0240{\sqrt{c}}\;-\;0.0640c\;+\;0.03268c^2\;at\;25^{\circ}C$Gruneisen effect appeared in the dilute solution, whereas anti-Gruneisen effect was found for the extremely dilute solution. No satisfactory interpretation for the variation of the viscosity with concentration can be found at the present.

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Effects of Straw Size and Thawing Rate on Post-thaw Quality of Bog Semen (개의 동결 정액 제조시 Straw의 크기와 융해온도가 정자의 생존율에 미치는 영향)

  • Son J.M.;Kim Y.S.;Shin Y.J.;Lim Y.H.;Yoon K.Y.;Lee D.S.;Shin S.T.;Cho J.K.
    • Journal of Embryo Transfer
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    • v.21 no.1
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    • pp.77-83
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    • 2006
  • 본 연구는 개 동결 정액 융해 시 straw 크기 및 융해 속도가 융해 정자의 질(quality)에 미치는 영향을 조사하고 최적의 융해 조건을 조사하는데 그 목적이 있다. 정상적인 번식능을 가진 비글 수컷 5마리에서 정액을 채취하여 원심 분리하여 정장을 버리고 남은 정자에 동결보호제인 glycerol이 첨가된 tris-glucose-egg yolk extender를 첨가하여 동결하고 액체질소에 보관한 후 융해하였다. 동결 융해 조건에 따른 효과를 알아보기 위해 straw는 0.25 ml과 0.5 ml크기를 사용하였고 융해 조건은 $75^{\circ}C$에 10초, $55^{\circ}C$에 12초 및 $37^{\circ}C$에서 120초로 하여 융해 후 정자의 활력도(vigor), 운동성(motility), Hypo-osmotic test(HOS test)를 이용한 생존성(viability) 및 $SperMac^{\circledR}$ 염색을 하여 정자의 membrane integrity를 비교 조사하였다. 조사 결과 0.5 ml 크기의 straw를 사용한 경우 $37^{\circ}C$ 융해가 $55^{\circ}C,\;75^{\circ}C$ 융해보다, 0.25 ml 크기의 straw를 사용한 경우에는 $37^{\circ}C,\;55^{\circ}C$ 융해가 $75^{\circ}C$ 융해보다 유의적으로 높은 활력 지수 및 생존성을 보였다(P<0.05). Straw크기에 따라 비교하였을 경우 0.5 ml 군에서 유의적으로 높은 활력도, 생존성 및 membrane integrity를 보였다(P<0.05). 결론적으로 개 정액이 동결 및 융해 시 0.5ml straw를 이용하여 동결한 후 $37^{\circ}C$에서 120초 동안 융해하는 것이 최적의 조건임이 사료된다.

COMPARISON OF MICROLEAKAGE OF NEW GENERATION DENTIN BONDING SYSTEM (자가부식 전처치제를 이용한 상아질 결합재의 미세 누출에 관한 연구)

  • Kim, Jong-Soo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.26 no.1
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    • pp.53-61
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    • 1999
  • Newley developed dentin bonding system which contains self-etching primer performed the removing of smear layer and etching procedure at once. So, it make possible more simple and shorter working time, the stronger bonding strength than conventional dentin bonding system. Cavities were prepared in the buccal and lingual surface of 30 extracted primary molars, and randomly assigned into three equal groups of 10 each. All cavities were filled with Z-100 composite resin following manufacturer's specifications after priming of three different dentin bonding system. Specimens stored for 7 days in 37 degree C water, thermocycled for 1000 cycles between 5 degree C and 55 degree C, immersed in 50% silvernitrate solution for 24 hours, and embedded in resin before being sectioned longitudinally. Data were analyzed by t-test and ANOVA. Mac-Bond II and Clearfil Linear-Bond II showed less microleakage at the occlusal and gingival margins compared to Scotchbond Multi Purpose. All dentin bonding systems showed significantly less microleakage at the occlusal margins compared to the gingival margins. But, there were no significantley difference between each group.

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분만후 젖소의 자궁내 미생물상 조사 및 Lipopolysaccharide의 분리

  • 백광수;김태일;우제석;전병순;박수봉;김현섭;이현준;홍의철;안병석
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 2003.10a
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    • pp.119-119
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    • 2003
  • 분만후 젖소의 자궁내 미생물상을 조사하고 미생물로부터 분리한 Lipopolysaccharide를 적용하여 소의 번식효율 증진에 기여하고자 분만후 젖소의 도축장 유래 자궁을 채취하여 혐기적 상태에서 균분리 동정을 실시하였다. 균분리 동정을 위하여, 시료를 1cm$\times$1cm로 채취하여 혐기상태에서 거품이 생길 때까지 vortexing한 후 균액 300$\mu l$를 뽑아 혐기배지에 도말하였고 도말한 plate는 $37{\circ}C$ 혐기chamber에서 24시간 배양하였다. 혐기배지에서 자란 균의 colony를 따서 Mac, BHI+B, BHI 배지에 배양한 후 Gram stain을 실시하였다. BHI 배지에서 자란 균의 colony를 따서 BUA+B 배지에 계대배양하였고 BUA+B 배지에서 자란 균중에 가장 마지막으로 자란 균을 따서 An-IF에 넣고 탁도를 63%T로 맞춘 후 An micro plate에 100$\mu l$씩 분주하였다. 분주한 plate를 $37{\circ}C$ 혐기 chamber에서 20~24시간 동안 배양한 후 Biolog를 실시하였다. 시료의 UV측정을 위하여 Sonic Processor로 세포를 분쇄하였고 분쇄한 세포를 $4{\circ}C$에서 10,000rpm으로 10분간 원심분리한 후 상층액을 분리하여 0.45$\mu m$ 필터로 여과한 다음 여과액을 취하여 UV로 standard(E.coli O26 B6 LPS)와 sample(10배 및 20배 희석액)을 측정하였다. (중략)

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Foraminoplastic Superior Vertebral Notch Approach with Reamers in Percutaneous Endoscopic Lumbar Discectomy : Technical Note and Clinical Outcome in Limited Indications of Percutaneous Endoscopic Lumbar Discectomy

  • Lee, Chul-Woo;Yoon, Kang-Jun;Ha, Sang-Soo;Kang, Joon-Ki
    • Journal of Korean Neurosurgical Society
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    • v.59 no.2
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    • pp.172-181
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    • 2016
  • To describe the details of the foraminoplastic superior vertebral notch approach (FSVNA) with reamers in percutaneous endoscopic lumbar discectomy (PELD) and to demonstrate the clinical outcomes in limited indications of PELD. Retrospective data were collected from 64 patients who underwent PELD with FSVNA from August 2012 to April 2014. Inclusion criteria were high grade migrated disc, high canal compromised disc, and disc protrusion combined with foraminal stenosis. The clinical outcomes were assessed using by the visual analogue scale (VAS), Oswestry Disability Index (ODI) and modified MacNab criteria. Complications related to the surgery were reviewed. The procedure used a unique approach, using the superior vertebral notch as the target and performing foraminoplasty with only reamers under C-arm control. The mean age of the 55 female and 32 male patients was 52.73 years. The mean F/U period was $12.2{\pm}4.2$ months. Preoperative VAS ($8.24{\pm}1.25$) and ODI ($67.8{\pm}15.4$) score improved significantly at the last follow-up (VAS, $1.93{\pm}1.78$; ODI, $17.14{\pm}15.7$). Based on the modified MacNab criteria, excellent or good results were obtained in 95.3% of the patients. Postoperative transient dysthesia (n=2) and reoperation (n=1) due to recurred disc were reported. PELD with FSVNA could be a good method for treating lumbar disc herniation. This procedure may offer safe and efficacious results, especially in the relatively limited indications for PELD.

On the Composition of Evaluation Questions Corresponding to Each Level in Matrix Chapter of the High School (행렬의 수준별 평가에 대한 연구)

  • Lee, Min-Jung;Lee, Yang
    • Journal of the Korean School Mathematics Society
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    • v.13 no.3
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    • pp.357-379
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    • 2010
  • There are many studies about the method of trying leveled class because we say the Excellence of Education after high school's Equalization Policy. After the leveled c1ass, Ministry of Education, Science and Tech. announced the induction of leveled classes' evaluation in 2008, it is called that students take classes adapted to their levels. This study illustrates criteria of forming evaluation, it composes leveled assessment tests referenced by Gibb's evaluation effects & Cotton's evaluation principles. Before anything else, this study induced contents of studies which is emphasized the structure rather than the arithmetic that is based on Foucault' s analysis of mathematics' class and examination & MacGregor's point of algebra. Since then we made leveled assessment tests which made by students' Question. And then, In this study, we modified evaluation tests appropriately by criteria of evaluation and analysing the result.

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Study on a Secure Authentication and Authorization Protocol based on Kerberos (커버로스 기반의 안전한 인증 및 허가 프로토콜 에 관한 연구)

  • 김은환;김명희;전문석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.5C
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    • pp.737-749
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    • 2004
  • Kerberos authenticates clients using symmetric-key cryptography, and supposed to Oust other systems of the realm in distributed network environment. But, authentication and authorization are essential elements for the security. In this paper, we design an efficient and secure authentication/authorization mechanism by introducing the public/private-key and installing the proxy privilege server to Kerberos. In the proposed mechanism, to make a system more secure, the value of the session key is changed everytime using MAC(message authentication code) algorithm with the long-term key for user-authentication and a random number exchanged through the public key. Also, we reduce the number of keys by simplifying authentication steps. Proxy privilege server certifies privilege request of client and issues a privilege attribute certificate. Application server executes privilege request of client which is included a privilege attribute certificate. Also, a privilege attribute certificate is used in delegation. We design an efficient and secure authentication/authorization algorithm with Kerberos.

A Study of the Nutritional Status and its Related Factors in the Elderly Hemodialysis Patients (노인 혈액투석 환자의 영양상태와 이에 관련된 요인에 관한 연구)

  • Park Kyung-Ae;Sim Yu-Mi;Kim Soon-Bae;Choi S-mi
    • Journal of Nutrition and Health
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    • v.39 no.2
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    • pp.133-144
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    • 2006
  • The purpose of this study was to evaluate the nutritional status and to identify related factors in elderly hemodialysis patients. Sixty-four patients who were registered in Asan Medical Center, Seoul, Korea, participated in the study. The data was collected between September and December, 2003. General characteristics were obtained with the use of an interviewer-administered questionnaire. Anthropometric and biochemical data, 3-day dietary records and dietary habits were also obtained. The results of this study were analyzed with t-test or $X^2$-test using SPSS package program. The percentage of elderly hemodialysis patients who were undergoing mild to severe malnutrition (MN group) and were normal nutrition (NN group) by subjective global assessment (SGA) criteria were 46.9% and 53.1 %, respectively. Appetite (p < 0.05) and dietary cholesterol intakes (p < 0.05) were significantly lower in MN group than the NN group. Body mass index (BMI, p < 0.001), lean body mass (LBM, p < 0.05), triceps skinfold thickness (TSF, p < 0.01), mid ann circumference (MAC, p < 0.01) and mid ann muscle circumference (MAMC, p < 0.05) were also lower in the MN group than the NN group. There were also significant differences in blood urea nitrogen (BUN, p < 0.05), creatinine (p < 0.05), prealbumin (p < 0.001) and C-reactive protein (CRP, p < 0.05). SGA was negatively correlated with serum BUN, creatinine and pre albumin, dry weight, BMI, LBM, total body water, TSF, MAC and MAMC, and positively correlated with age. In stepwise multiple regression analysis, SGA was related to BMI, CRP, age and BUN. In conclusion, almost half of the subjects were in malnourished status and had lower values in anthropometric and biochemical data. Our results suggest that SGA is a simple and adequate method for assessing the nutritional status in elderly hemodialysis patients and adequate dietary guidelines based on individual nutritional status are needed in the patients.

Immunohistochemical Study on the TNFα-Secreting Macrophages and Endothelial Cells in the Porcine Corpus Luteum (돼지 황체에서 TNFα-분비 대식세포와 내피세포에 관한 면역조직화학적 연구)

  • Park, C.S.;Han, S.R.;Kim, S.I.;Cho, K.J.;Kim, W.S.
    • Journal of Animal Science and Technology
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    • v.47 no.5
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    • pp.711-720
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    • 2005
  • In the corpus luteum, TNF$\alpha$ is known to induce functional and structural luteolysis. In addition, it acts as luteotropic agent during the initial and early stage of luteal development. In spite of its importance in corpus luteal development, there is still different opinions for the source cells of TNF$\alpha$ in the corpus luteum. One is the macrophages only, and the other is macrophages are the main source and endothelial cells are the minor source. In this experiment, using the porcine corpora lutea of pregnancy and ovulatory stages, hematoxylin-eosin stain, macrophage and TNF$\alpha$ immunohistochemistry were carried to reveal the sources of TNF$\alpha$. As a result, MAC 387-positive macrophages were present in all the stages of corpora lutea. In the mature corpora lutea of nonpregnant stages, the sites of MAC 387-positive macrophages and those of TNF$\alpha$- positive macrophages were coincided, and the sites of endothelial cells and those of TNF$\alpha$-positive endothelial cells were nearly coincided. But, in the mature CL of pregnant stage, mid- and advanced luteolytic stages of both nonpregnant and pregnant stages, the sites of MAC 387-positive macrophages and those of TNF$\alpha$-positive macrophages were coincided, but not in the endothelial cells. Accordingly, it can be concluded that macrophages are the main source of TNF$\alpha$ in the corpus luteum and endothelial cells are the minor source in the mature and mid-lytic stages, but, in the advanced luteolytic stage, macrophages are the only source of TNF$\alpha$.