• Title/Summary/Keyword: $^{129}I$

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An Experimental Study on the Dynamic Characteristics of a Planetary Gear Train in the Low Speed Region (유성치차열의 저속영역에서의 동특성에 관한 실험적 연구)

  • Lee, J. H.;Cheon, G. J.;Kim, J. H.;Kim, C.;Han, D. C.;Myung, J. H.;Jeong, T. H.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.5 no.4
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    • pp.121-129
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    • 1997
  • Gear train system test rig of power circulating type was fabricated, and systematic experiment for measuring dynamic characteristics of the planetary gear trains in the low speed region has been carried out using the test rig. The measured parameters are fillet strains of the sun gear and ring gear, carrier displacements, torques of the input and output shafts. The results are as follows : i) Even though the loading torque is constant, torque variation has been observed on the input and output hafts, ii) The variation of the torque has two frequency components, i.e. lower one of the input shaft rotation and higher one of the two teeth meshing, iii) The variation of the fillet strains shows the same tendency as that of the torque, iv) The loci of the carrier depend on the torque and rotational speed.

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A Study on the Applicability of 2-Poisson Model for Selecting Korean Subject Words (2-포아송 모형을 이용한 한글 주제어 선정에 관한 연구)

  • 정영미;최대식
    • Journal of the Korean Society for information Management
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    • v.17 no.1
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    • pp.129-148
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    • 2000
  • Experiments were performed on three subsets of a Korean test collection in order to determine whether 2-Poisson model's Z value is a good measure for selecting subject words from a document to be indexed. It was found that subject word selection based on the Z value was effective for only one subset with short texts, i.e., the Science and Technology subset. Correlation analyses between 2-Poisson model's Z and TF.IDF weight for the three subsets showed that the correlation was relatively high for two test subsets with short texts, i.e., the Science and Technology subset and the Newspaper subset.

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Improvement of Electrostatic Discharge (ESD) Protection Performance through Structure Modification of N-Type Silicon Controlled Rectifier Device (N형 실리콘 제어 정류기 소자의 구조 변형을 통한 정전기 보호성능의 향상에 대한 연구)

  • Yang, Jun-Won;Seo, Yong-Jin
    • Journal of Satellite, Information and Communications
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    • v.8 no.4
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    • pp.124-129
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    • 2013
  • An electrostatic discharge (ESD) protection device, so called, N-type SCR with P-type MOSFET pass structure (NSCR_PPS), was analyzed for high voltage I/O applications. A conventional NSCR_PPS device shows typical SCR-like characteristics with extremely low snapback holding voltage, which may cause latch-up problem during normal operation. However, a modified NSCR_PPS device with counter pocket source(CPS) and partial p-type well(PPW) structure demonstrates highly latch-up immune current-voltage characteristics.

Effect of Dimethyl Sulfoxide on Economic Traits and the Change of Some Metabolic Sustances of Bivoltine Silkworm, Bombyx Mori L.

  • Nirwani, R.B.;Hugar, I.I.;Kaliwal, B.B.
    • Journal of Sericultural and Entomological Science
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    • v.38 no.2
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    • pp.124-129
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    • 1996
  • Oral application of dimethyl sulfoxide in different concentration (1, 3 and 5 percent) to silkworm, Bomyx mori at the fourth and the fifth instar has significantly increased the commercial characters such as larval and silkgland weights, female and male cocoon weights, their shell weights and egg production. However, larval duration, cocooning and hatching percentages did not showed any significant change, as compared with that of the corresponding parameters of the carrier control. Similarly the glycogen and protein contents of the fat body and trehalose and protein contents of the haemolymph were significantly increased in 1 and 3 percent, whereas the increase of them in 5 percent concentration did not take place significantly, except haemolymph trehalose where it was found to be significant, as compared with that of carrier control.

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A Study of Extracting Acoustic Parameters for Individual Speakers (개별화자의 음성파라미터 추출에 관한 연구: 음성파라미터의 상관관계를 중심으로)

  • Ko, Do-Heung
    • Speech Sciences
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    • v.10 no.2
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    • pp.129-143
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    • 2003
  • Fundamental frequency (Fo), jitter, shimmer, and harmonics-to-noise ratio (NHR) have been measured to see their interactions between the parameters using Multi-Dimensional Voice Program (MDVP). 100 Korean normal adults (50 males and 50 females) ranging from their early 20's to their early 30's produced the eight sustained vowels including /a/, /i/, /u/, /c/, /e/,/$\varepsilon$/, /i/, and /e/. The subjects were asked to read the above vowels five times in isolation with the interval of five seconds, respectively. Male voices, on the average, showed 130.7 Hz in Fo, 0.6696% in jitter, 1.8151% in shimmer, and 0.12 in NHR, while female voices showed 232.8 Hz in Fo, 0.9222% in jitter, 1.9199% in shimmer, and 0.1098 in NHR. As to the correlation coefficient, it was found that for male speakers jitter vs. shimmer, shimmer vs. NHR, Fo vs. shimmer, and Fo vs. NHR are statistically significant. It was found that for female subjects jitter vs. shimmer and Fo vs. shimmer are statistically significant. However, it is concluded that the correlation coefficient in females are not meaningful in a practical way though they are all statistically significant.

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The vertical environmental characteristics in the tidal flat sediments (갯벌의 수직적 환경 특성)

  • 김종구;유선재
    • Journal of Environmental Science International
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    • v.9 no.2
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    • pp.125-129
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    • 2000
  • As one of the fundamental survey to evaluate purification capacity of pollutants at the tidal flat sediments, we studied vertical environmental characteristics in three tidal flat sediments, Chunjangdae, Eueunri and Gyewhado. These are dissmilar to external feature in each other. The results of this study may be summarized as followed; As the results of particle analysis, Eueunri tidal flat fediment located in Keum river estuary consists of 98.98% as silt & clay, Chunjangdae tidal flat sediment located in SeocheonGun consists of 97.99% as sand. And Gyewhado tidal flat sediment located in Saemankeum in Saemankeum area consists area consists of 32.81% as silt & clay and 67.19% as sand. The concentration of organic pollutants(I.L., COD, POC, PON) in Eueunri tidal flat sediment which highly content of silt & clay were 3~4 times higher than others. The concentration of organic pollutants at each layer were slightly increase goes with deepen layer. The linear correlation between I.L. and COD, POC, PON were obtained. Correlation coefficients were in range of 0.821~0.940. Also the correlation between pH and COD, POC, PON were high(>r=0.9). Filteration rate in Chunjangdae tidal flat sediment was 0.01584cm/s as mean value, but the other were almost nothing filtered off.

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Studies on the Mineral Content of Edible Mushrooms (식용 버섯류의 무기물 함량)

  • 허윤행;김옥경
    • Journal of Environmental Health Sciences
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    • v.17 no.1
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    • pp.129-135
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    • 1991
  • To investigate on the trace element content of twelve edible mushrooms and Aloe arborescens, i. e., Lentinus edodes, Ganoderma lucidum (culturing in wood and soil), Tricholoma matsutake, Agaricus bisporus, Cyrophora esculenta, Auricularia auricula-Jude (produced in Korea and China), Sarcodon asparatus, Pleurotus ostreatus, Coriolus versicolor, Smilax rotundifolia and Aloe arborescerts were analyzed by Atomic absorption spectrometer. The obtained results were summerized as follows: 1. Potassium, sodium, magnesium and iron content for the most part samples were in large quantities, especially phosphorus content of those was highest ammount for the all samples. 2. Sodium content was much ammount in the Lentinus edodes (39mg) and Ganoderma lucidurn (20 mg), Culturing in wood and soil, while potassium was very high ammount in the Aloe arborescens and other samples. Mush ammount of magnesium as compared with others was Lentinus edodes (144mg), Ganoderma lucidurn (128mg), Aloe arborescerts (50mg) and pleurotus ostreatus (60mg). Phosphorus content of Ganoderma lucidurn, Lentinus edodes, Gyrophora esculenta, Auricularia polytricha and Agaricus bisporus was much ammount while iron content of all samples equality higher ammount. Sodium content of Aloe arborescens was not analyzed out for almost all, its potassium (82mg), magnesium (50mg) and iron (18rng) content comparatively higher quentity than others minerals and phosphorus volume (4.9mg) as compared with others, was conspicuously lower detect. 4. Cadimium and lead content of harmful metal element were detected on trace quentity for the most part samples 5. Organic acids of samples i.e., Legtinus edodes, Agaricus bisporus, Pleurotus ostreatus and Ganoderma lucidum were Citrate, Malate, Fumalate, Succinate, Oxalate, Acetate, Lactate, and Tartarate and Citrate, Malate and Fumarate contents were higher amount remarkbly than other organic acids. Tartarate content was trace amount.

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A Study on the coverage of e-commerce insurance (전자상거래 보험의 담보범위에 관한 고찰)

  • Shin, Gun-Hoon
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.27
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    • pp.129-161
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    • 2005
  • Todays, computers in business world are potent facilitators that most companies could not without them, while they are only tools. They offer extremely efficient means of communication, particularly when connected to Internet. What I stress in this article is the risks accompanied by e-commerce rather than the advantages of Internet or e-commerce. The management of e-commerce companies, therefore, should keep in mind that the benefit of e-commerce through the Internet are accompanied by enhanced and new risks, cyber risks or e-commerce risks. For example, companies are exposed to computer system breakdown and business interruption risks owing to traditional and physical risks such as theft and fire etc, computer programming errors and defect softwares and outsider's attack such as hacking and virus. E-commerce companies are also exposed to tort liabilities owing to defamation, the infringement of intellectual property such as copyright, trademark and patent right, negligent misrepresent and breach of confidential information or privacy infringement. In this article, I would like to suggest e-commerce insurance or cyber liability insurance as a means of risk management rather than some technical devices, because there is not technically perfect defence against cyber risks. But e-commerce insurance has some gaps between risks confronted by companies and coverage needed by them, because it is at most 6 or 7 years since it has been introduced to market. Nevertheless, in my opinion, e-commerce insurance has offered the most perfect defence against cyber risks to e-commerce companies up to now.

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Design of Propulsion Shafting System for Controllable Pitch Propeller (I : Latout Design with Sizing) (가변추진기 추진축계시스템의 설계 (제 I 보 : 외형설계 ))

  • 김기인;전효중;박명규;김정렬
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2002.05a
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    • pp.129-134
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    • 2002
  • This study is focused on the layout design with sizing for the main propulsion shafting with controllable pitch propeller system. For appropriate design and successful manufacturing of controllable pitch Propeller system, it is based on specifications to be required from the customer as well as the stresses calculation and analysis of main propulsion system for hollow shafting. And it must be performed according to the U.S military specifications MIL-STD-2189(SH) with drawing of NAVSHIPS 803-2145807, and also the stress analysis by applying safety factor. The results are as follows : 1. For the main propulsion system with controllable pitch propeller, it is designed the following items propeller diameter, hub diameter, dimensions of oil distribution or actuating unit based on shaft mounting type, diameters of propeller and intermediate shaft, dimension of split muff coupling, coupling flange thickness and of coupling bolt diameter. 2. As the results, we can get complete our own design ability for the main propulsion shafting with controllable pitch propeller system with critical data which are necessary to establish shafting arrangement from the ship building companies.

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A Comparative Study on the Modern Architectural Movement in Catholic Church - Focused on the 'Riturgical Movement' and 'L' art $Sacr\'{e}$ Movement' in Europe in the first half of 20th century - (20세기 현대교회건축 운동에 관한 비교 연구 - 독일의 전례운동과 프랑스의 성미술운동을 중심으로 -)

  • Kim, Jung-Shin
    • Journal of architectural history
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    • v.8 no.4 s.21
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    • pp.129-146
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    • 1999
  • The Purpose of this Study is to find the Modern Movements which had done important roles on the development of modern church architecture and sacred art in the first half of 20th century. I had investigated the background and process of the movements, and analyzed the buildings which represented the movements. And I compared the architectural fruits of 'Riturgical Movement' and 'L' art $Sacr\'{e}$ Movement. The results are summarized as follows : First, there are two important movements in Catholic church in the backgrounds of the innovative changes of modern church architecture, Those are 'Riturgical Movement' which pursuits to establish a closer relation between clergy and congregation, and to make the positive participants in the service not mere observers and 'L' art $Sacr\'{e}$ Movement' which pursuits to accept modern secular art into church. Second, both movements had been developed on the bases of the theological studies with tow monasteries - Benedictine Order and Dominican Order - as leader. And the main concept was a kind of revival movement which recovers the Christian tradition. Third, The two movements began from the different themes and in the different regions. But they exerted influences each other, and achieved successful fruits in the Catholic churches of England and Swiss in 1960'. Fourth, 'Riturigical reformation' and 'Acceptance of modern art' had been officialized and generalized through the second Vatican Council(1962-1965).

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