• Title/Summary/Keyword: Frequency of appearance

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Optimization of Nd:YAG laser welding parameters for sealing the small Ti tube ends (소형 티타늄 튜브 끝의 밀봉용접을 위한 Nd:YAG 레이저 용접조건의 최적화)

  • Lee Hyeong Geun;Han Hyeon Su;Son Gwang Jae;Hong Sun Bok
    • Proceedings of the KWS Conference
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    • v.43
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    • pp.73-75
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    • 2004
  • The purpose of this study is to optimize Nd:YAG laser welding parameters to seaz a Rf source into a Ti micro capsule. Ti tube ends can be sealed as some length of ぉbe end is melted and coalesced. The exact control of the melted length is the most important to get sound sealing. The Nozzle type, tube rotating speed, tilt angle, focal position, pumping voltage, pulse frequency and pulse width were selected as the Nd:YAG laser welding Parameters. These Parameters were optimized by the Taguchi experimental method using 115 orthogonal array. Appearance and cross section of the seated tube ends were examined by SEM.

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Critical and Flutter Speeds of Rotating Disks in Information Storage Devices (정보저장기기용 회전디스크의 임계속도 및 플러터 속도에 관한 연구)

  • 이승엽;윤동화
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.484-489
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    • 2001
  • Recent trends in information storage devices disk are the transition from CD drives to high density DVD drives, the development of writable disk drives and the appearance of several high-density portable disk drives. In some flexible disk drives, self-excited disk vibrations become severe as rotation speed increases near or above critical speed. Critical speeds of CD/DVD, ASMO and floppy disks are experimentally measured and compared with analytical predictions. Flutter instability caused by aero-induced disk vibration at high speeds are experimentally observed. In ASMO, three nodal-diameter mode experiences its flutter at 8750 rpm with the frequency lock-on phenomenon. The CD/DVD disk does not have the aero-induce flutter up to 14,000 rpm.

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QUASI-PERIODICITY AND CHAOTIC CONVECTION IN A HORIZONTAL ANNULUS WITH A CONSTANT HEAT FLUX WALL (일정 열 유속 벽을 갖는 수평 환형 공간에서의 준주기성과 혼돈대류)

  • Yoo, Joo-Sik
    • Journal of computational fluids engineering
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    • v.16 no.3
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    • pp.52-58
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    • 2011
  • This study investigates the bifurcation sequence to chaos in a horizontal annulus with a constant heat flux wall. After the first Hopf bifurcation from a steady to a simple time-periodic flow with a fundamental frequency, quasi-periodic flows with two or three incommensurable frequencies appear. A reverse transition from a quasi-periodic flow to a simple periodic flow is observed with increase of Rayleigh number. And finally, chaotic convection is established after appearance of three incommensurable frequencies at a high Rayleigh number. Simple periodic flows exist between quasi periodic flows. The transition route to chaos of the present simulations follows the Ruelle-Takens route.

Simultaneous Observation of Fe-F and F-Fe-F Stretching Vibrations of Fluoride Anion Ligated Tetraphenylporphyrin Iron(Ⅲ) by Resonance Raman Spectroscopy

  • 이인숙;신지영;남학현;김도균;팽기정
    • Bulletin of the Korean Chemical Society
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    • v.18 no.7
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    • pp.730-733
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    • 1997
  • Monofluoroiron(Ⅲ) tetraphenylporphyrin, Fe(TPP)F, and difluoroiron(Ⅲ) tetraphenylporphyrin, [Fe(TPP)F2]- were generated in a various non-aqueous solvents by the reaction between Fe(TPP)Cl and tetrabutylammonium fluoride TBAF 3H2O. Formation of the these complexes was detected by the appearance of the ν(F-Fe) (ν, stretching vibration) at 506 cm-1 for Fe(TPP)F and the ν(F-Fe-F) at 448 cm-1 for [Fe(TPP)F2]-, simultaneously, with 441.6 nm excitation by Resonance Raman (RR) spectroscopy. These assignments were confirmed by observed frequency shifts due to 56Fe/54Fe and TPP/TPP-d8/TPP-N15 isotopic substitutions. Difluoroiron complex is an iron(Ⅲ) high-spin complex with the oxidation sensitive band at 1347 cm-1 for ν4 and core size/spin state sensitive band at 1541 cm-1 for ν2.

Immediate Toe-to-Hand Transfer in Acute Hand Injuries (급성 수부 손상시 즉시 족지 전이술)

  • Woo, Sang-Hyun;Kim, Hak-Soo
    • Archives of Reconstructive Microsurgery
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    • v.11 no.1
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    • pp.19-28
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    • 2002
  • From 1994-2001, 25 mutilated digits were reconstructed with immediate toe-to-hand transfer in acute hand injury in 21 patients. There were 15 cases of great toe-to-hand transfer(partial great toe transfer 8 cases, modified wrap-around procedure 2 cases, and trimmed great toe transfer 2 cases) for thumb reconstruction, 2 cases of second toe transfer for index reconstruction, and 4 cases of simultaneous two toe-to-hand transfer(great toe & second toe transfer 1 case, bilateral second-toe transfer 2 cases, combined second & third toe transfer 1 case) for reconstruction of multiple digit amputations. Two cases of emergency exploration(2/25, 8%) were successfully salvaged. The incidence of emergency exploration and postoperative infection was not significantly different from that of the elective toe-to-hand transfer cases. Duration of industrial insurance coverage was 225 days, which is much shorter than that of elective cases. Among 43% of patients maintained their original job even after injury and immediate toe-to-hand transfer. The subjective satisfaction self- assessment scores of aesthetic appearance and function on the new reconstructed thumb were 80 and 88 in average, respectively, over a total score of 100. These were higher than those of reconstruction of other digits, but lower than those of elective reconstruction. The donor site after harvest of the great toe was mostly unsatisfied in a view of appearance. Immediate toe-to-hand transfer provides many advantages over elective procedure in acute hand injuries such as single stage reconstruction, shortened convalescent period, early return to work and efficient socio-economic factor. Furthermore because there were no significant differences in success rate, frequency of complications or ultimate functional result, immediate toe-to-hand transfer is a safe and reliable procedure in case of limited indications for acute digits loss.

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Study on the Perceived Stress Degree and Content of Mother of High-Risk Infants in Neonatal Intensive Care Unit (신생아 집중실에 입원한 고위험 신생아 어머니의 스트레스 정도 및 내용에 관한 연구)

  • Sung Mi-Hae
    • Child Health Nursing Research
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    • v.8 no.1
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    • pp.97-109
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    • 2002
  • This study was conducted to understand the degree and contents of stress which the mothers of high-risk infants can be experienced from the hospitalization of ICU for their new borns, and thus to offer the basic program to he nursing intervention program for these. Subjects were the 171 mother of hospitalized newborn in NICU of 1 University Hospital in Busan from June, 20, 2001 to September, 15, 2001, who agreed to take part in this study. The instruments used in this study were Parental Stressor Scale:NICU(PSS:NICU) developed by Miles et al. The questionnaire has 4 dimensions and 45 items ; sight and sounds of NICU(5 items), babies' appearance and behavior nursing intervention(19 items), parental role alteration and relationship with their baby(10 items), health team communication(11 items). The data was analysed as average, frequency, Standard Deviation, t-test, ANOVA, Pearson correlation coefficient by use of SPSS/PC+. The results of this study are as follows ; 1. The total perceived stress level score of mothers of high-risk infants was slightly high(3.44±0.71). The highest scored dimension was 'appearance and behavior of the baby'(4.06±0.80), and next were 'relationship with their baby and parental role change'(3.55±0.98), 'sight and sounds of NICU'(3.22±1.01), 'communication with health team'(2.93±0.91). 2. The total perceived stress level score was significantly correlated with birth weight (F=2.35, p<.05). 3. In sight and sounds of NICU, the perceived stress level score was significantly correlated with nursing in the incubator(t=2.28, p<.05) and birth weight(t=2.26, p<.05). In summary, information about physical environment of NICU, birth weight and nursing in the incubator must be included in nursing intervention program of mother's of high-risk infants in reducing the patents stress level. And, it is suggested that there need to find the coping mechanism of mother of high-risk infants.

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Pathophysiology of orthostatic tremor: a multiple case study (길입성 진전의 병태생리: 다증 증례 연구)

  • Seo, Man-Wook;Lee, Kwang-Woo
    • Annals of Clinical Neurophysiology
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    • v.4 no.1
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    • pp.44-50
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    • 2002
  • Introduction : Orthostatic tremor develops in the legs while standing up with no weakness, pain or imbalance in the leg and the tremor is characteristically not observed when walking. However there have been some confusions about orthostatic tremor in several aspects. For the past ten years, we have observed 4 patients with orthostatic tremor. In each case tests were performed to investigate the following three important areas of inquiry about orthostatic tremor. Firstly, whether this disorder is an independent diagnostic entity or a variant of essential tremor. Secondly, whether the progress of this disorder is specifically related with standing posture. Lastly, the nature of the pathophysiologic mechanism behind the appearance of the tremor when standing after the lapse of a certain latent period and its disappearance upon the commencement of walking. Methods : Our 4 cases of orthostatic tremor were studied clinically, electrophysiologically, and pharmacologically. Electrophysiological tests included tremor spectrum test and electromyography. Results : We observed the presence of this tremor in several other tonic postures, as well as its absence, in a vertically lifted position from all our cases. Our cases registered a variable tremor frequency between 5 and 12 Hz according to the tremor spectrum test and EMG. Furthermore all our 4 cases demonstrated patterns of both synchronous EMG activity and alternating EMG activity at various times in homologous muscles of both legs. Orthostatic tremor was improved significantly with propranolol as well as clonazepam. Conclusions : From the results of our study we drew the following conclusions. It is probable that orthostatic tremor is simply a variant of essential tremor rather than being an independent diagnostic entity and that in most cases its development is specifically related with muscle contraction rather than merely with the act of standing. Furthermore we discovered a clue in the previously described neural control mechanism that the nuclear bag fibers in the muscle spindle have lag time of several seconds in their response to muscle strength and that their baseline does not reset fully in rapidly moving muscle. This neural control mechanism could offer sufficient explanation for the phenomena of tremor appearance when standing and disappearance when walking in orthostatic tremor.

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Analysis of Current Status of Marine Products and Characteristics of Processed Products Seafood in Joseon - via the Veritable Records of the Joseon Dynasty based data - (『조선왕조실록(朝鮮王朝實錄)』 속 수산물 현황과 가공식품 특성 분석)

  • Kim, Mi-Hye
    • Journal of the Korean Society of Food Culture
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    • v.37 no.1
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    • pp.26-38
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    • 2022
  • This study used the big data method to analyze the chronological frequency of seafood appearance and variety mentioned by the veritable records of the Joseon dynasty. The findings will be used as a basis for Joseon Period's food cultural research. The web-crawling method was used to digitally scrap from the veritable records of the Joseon dynasty of Joseon's first to the twenty-seventh king. A total of 9,536 cases indicated the appearance of seafood out of the 384,582 articles. Seafood were termed "seafood" as a collective noun 107 times (1.12%), 27 types of fish 8,372 times (87.79%), 3 types of mollusca (1.28%), 18 types of shellfish 213 times (2.23%), 6 types of crustacean 188 times (1.97%), 9 types of seaweed 534 times (5.60%). Fish appeared most frequently out of all the recorded seafood. Sea fish appeared more frequently than the freshwater fish. Kings that showed the most Strong Interest Inventory (SII) were: Sungjong from the 15thcentury, Sehjo from the 15th, Youngjo from the 18th, Sehjong from the 15th, and Jungjo from the 18th respectively. Kings of Chosen were most interested in seafood in the 15th and 18th centuries.

A Research of Apperance-mnagement Bhavior in 20-40's women according to Degree of Apperance Concern (20-40대(代) 여성(女性)의 외모관심도(外貌觀心度)에 따른 외모관리행동(外貌管理行動))

  • Kim, Sung-Nam;Lee, Kyoung-Sook
    • Journal of Fashion Business
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    • v.11 no.4
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    • pp.29-41
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    • 2007
  • This study is to research how women aging from 20 through 40 Apperance -Mnagement Bhavior and care of their outer looks from a beauty treatment perspective. This research should help satisfy the wants of women who are the main clients of the beauty products and help the beauty industry to produce new products and also to help out on their marketing strategy. In order to search the general characteristics of our target women, Frequency Analysis was used, to find out the sub-factor of interest in beauty Factor Analysis and Reliability Analysis was used. In order to divide the group according to Degree of Apperance Concern 'sub-factor, cluster analysis, analysis of variance, Scheffe'-test, $X^2-test$ was used, and to find out the difference on how they care of beauty analysis of variance was used, and further more to summarize the result of analysis of variance Scheffe'-test was used. As a result, in all different ways of beauty caring, weight resisting, skin care and plastic surgery summed up similarly among the self-care group, hair care ended up with similar results among all three groups: self-caring group, no interest in beauty at all group, and the too conscious of other eyes group, and results on the interest rate of clothing ended up similarly among the other-eye conscious group, beauty care interest group, and the self-care group.

Pathogenicity in Nursery Box and Symptom Appearance and Yield Damage in Paddy Field by Each Strain of Fusarium moniliforme (Fusarium moniliforme의 Strain 별(別) 육묘상(育苗床)과 본답(本畓)에서 병(病) 발생(發生)과 피해(被害) 해석(解析)에 관한 시험(試驗))

  • Sung, Jae-Mo;Yang, Sung-Suk;Lee, Eun-Jong
    • The Korean Journal of Mycology
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    • v.12 no.2
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    • pp.65-73
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    • 1984
  • Strain IV caused highest reduction of germination and caused abnormal elongation of all part of the plant which finally died. Milyang 23 and Nampungbyeo formed mesocotyl. Samnambyeo and Jinjubyeo did not formed mesocotyl on the soil surface in nursery boxes when they were planted on soil infested with each strain of F. moniliforme. Infected seedlings with mesocotyl recovered after transplanting in the the field. The most frequency of Strain IV was isolated from infected rices and this strain was isolated from all part of rice. When rice seedling infected with Strain IV were transplanted in paddy field, most of rice showed Bakanae symptom. Ear emergence of rice was more delayed when seedlings infected with Strain IV were transplanted than that of healthy plant. Number of panicle per hill and grain yield from rice when infected rice seedling by Strain IV were transplanted were more decreased than that of the healthy plant in paddy field.

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