• 제목/요약/키워드: Height variation

검색결과 1,128건 처리시간 0.023초

HDD용 에어베어링 슬라이더의 강건설계에 관한 연구 (A Robust Design Study of Air Bearing Slider for HDD)

  • 전규찬;장동섭;좌성훈
    • Tribology and Lubricants
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    • 제16권4호
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    • pp.247-252
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    • 2000
  • As the demand for higher areal recording densities requires a lower flying height of the slider, the variation of the flying height of the slider during drive operation becomes of great concern. The variation of the flying height is closely related with the slider design parameters such as air bearing shape, cavity depth, shallow step depth, crown, camber, pitch offset, roll offset, gram load, and so on. The objective of this work is to optimize the cavity depth and the shallow step depth, which are the control factors in air bearing design, using Robust Design method. It was found that the shallow step depth was statistically significant in affecting the variation of flying height, therefore the level of the shallow step depth should be chosen to minimize the variation of flying height.

Analysis of Electrical Properties of Ti/Pt/Au Schottky Contacts on (n)GaAs Formed by Electron Beam Deposition and RF Sputtering

  • Sehgal, B-K;Balakrishnan, V-R;R Gulati;Tewari, S-P
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제3권1호
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    • pp.1-12
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    • 2003
  • This paper describes a study on the abnormal behavior of the electrical characteristics of the (n)GaAs/Ti/Pt/Au Schottky contacts prepared by the two techniques of electron beam deposition and rf sputtering and after an annealing treatment. The samples were characterized by I-V and C-V measurements carried out over the temperature range of 150 - 350 K both in the as prepared state and after a 300 C, 30 min. anneal step. The variation of ideality factor with forward bias, the variation of ideality factor and barrier height with temperature and the difference between the capacitance barrier and current barrier show the presence of a thin interfacial oxide layer along with barrier height inhomogenieties at the metal/semiconductor interface. This barrier height inhomogeneity model also explains the lower barrier height for the sputtered samples to be due to the presence of low barrier height patches produced because of high plasma energy. After the annealing step the contacts prepared by electron beam have the highest typical current barrier height of 0.85 eV and capacitance barrier height of 0.86 eV whereas those prepared by sputtering (at the highest power studied) have the lowest typical current barrier height of 0.67 eV and capacitance barrier height of 0.78 eV.

수평채널 밑면에 부착된 단일 발열모듈에서 채널높이의 변화에 따른 냉각특성 연구 (The Study about Cooling Effect of a Heated module in a Horizontal Channel with a Variation of Channel Height)

  • 이진호;유갑종;장준영;김병하
    • 설비공학논문집
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    • 제13권5호
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    • pp.348-355
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    • 2001
  • The coupled conduction and convection heat transfer from a protruding heated module in a horizontal channel with a variation of channel height is experimentally investigated. The input power to the module is 3, 7W and thermal resistance of module support is 0.06 , 1.03 and 158K/W. the Reynolds number ranged from 350 to 4500 corresponding to the inlet velocity(0.4~1.3 m/s) and channel height(11~35 mm). The results were obtained that the decrease of thermal resistance of module support reduces the module temperature by redistributing the heat flux and the overall thermal resistance of the module. In the study the effect of channel height is very significant in the adiabatic condition, but negligible in the conjugate condition. Finally, correlations for Nusselt number and $Q_B$/Q with a variation of Reynolds number were developed respectively.

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Geographic Variation in Survival Rate and Height Growth of Pinus densiflora S. et Z. in Korea

  • Kim, In-Sik;Ryu, Keun-Ok;Song, Jeong-Ho;Kim, Tae-Su
    • 한국산림과학회지
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    • 제94권2호통권159호
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    • pp.73-81
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    • 2005
  • This study was conducted to examine the geographic variation among provenances of Pinus densiflora in survival rate and height growth at four test plantations (Jungsun, Chungju, Naju, and Jeju). The plantations were parts of the eleven provenance trials of Pinus densiflora established by Korea Forest Research Institute in 1996. The survival rate and height growth were significantly different among test plantations at $p{\leq}0.01$. Latitude and longitude of test plantation were negatively correlated with survival rate and height growth. On the other hand, annual mean temperature, mean temperature (Nov.~Feb.), extremely low temperature (Dec.~Feb.), and annual mean growing days of test plantation were positively correlated with these two. The relationships between growth variables and geographic variables were analysed with canonical correlation analysis. A considerable amount of variation in survival rate and height growth was explained by latitude, annual mean growing days, extremely low temperature (Dec.~Feb.) and extremely high temperature (Nov.~Feb.) of provenances. It is estimated that up to 47.1% and 67.4% of the genetic variability in survival rate and height growth was attributable to the environmental variability of the provenances, respectively. The response surface curve of survival rate and height growth was plotted against latitude and longitude to examine growth performance of provenances for each test site. Generally, the local provenances showed better survival rate and height growth.

20대 여성의 하반신 체형 유형에 따른 플레어스커트의 패턴 설계 (Pattern Making of the Flared Skirt According to the Lower Body Somatotype of the 20's Women)

  • 이연순;류지현;김경아
    • 한국의류산업학회지
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    • 제10권5호
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    • pp.660-667
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    • 2008
  • The purpose of this study was to modify a Flared Skirt for women according to the somatotype of lower body. The subjects for the wear test were 3 students, who were in $mean{\pm}1{\sigma}$ each somatotype. The results of this study are as follows: First, the Flared Skirt pattern was modified according to each type. The front waist line rising measurement proposed for type 1 and type 2 were 0.5cm, because of lower front silhouette with waist shape. The back waist line rising measurement proposed for type 2 was 1cm and type 3 was 0.5cm, because of lower back shape with hip. Second, the wave-height of nodes were regular at front and back in type 1. Also, the wave-height of nodes were evenly distributed side and center. The variation ratio of wave-height of back nodes were lower than existing pattern in type 2 and type 3. It means the variation ratio of wave-height of back nodes were regular in modification pattern. Altogether, modification patterns were more regular and lower than existing pattern in the number of nodes, the distribution ratio of nodes, the wave-height of node, the variation ratio of wave height of nodes.

칼라 꺾임선(線) 눕힘각도(角度) 변화(變化)에 따른 외곽치수(外廓値數) 및 스탠드량 변화(變化)에 관(關)한 연구(硏究) - 오픈 칼라를 중심(中心)으로 - (A Study on the Variation of Collar Edge and Height according to the Angles of Collar Roll Line - Based on the Open Collar -)

  • 임자영
    • 패션비즈니스
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    • 제9권2호
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    • pp.143-159
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    • 2005
  • This study was done to provide basic data for clothing design and thus to contribute to the academic development at the clothing and textile area and collar roll line lay down angle variation at collar width on the open collar. The study was composed as tallows: 1. The variation at collar outer wall size increase collar roll line lay down angle size the more Increase. 2. The outer wall and stand height size increase aware at variation collar width at the more Increase. It is desirable that this study will be at help to enchancement of life style in garments and promotion of garments industury by developing the archetype basic collar pattern suitable to Korean women's garments.

Heritability and Genetic Gains for Height Growth in 20-year-Old Korean White Pine in Korea

  • Shin, Man-Yong;Park, Hyung-Soon;Cho, Yoon-Jin;Chung, Dong-Jun
    • 한국자원식물학회지
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    • 제19권6호
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    • pp.677-679
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    • 2006
  • The objectives of this study were to examine the genetic variation of 20-year-old tree height and to estimate heritabilities and genetic gains of Korean white pine. Analysis of variance showed that families and family x block interaction had the significant (p=0.01) effects on tree height. However, family variation appears to be much greater than the variation due to family x block interaction. Individual tree heritability was higher ($h_I^2=0.73$) than family heritability, ($h_F^2=0.83$) therefore, combined selection showed the largest genetic gain (17.76%) in a given equal intensity of selection.

Effect of Barrier Rib Height Variation on the Luminous Characteristics of AC PDP

  • Bae, Hyun-Sook;Whang, Ki-Woong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.91-94
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    • 2003
  • We studied the effect of barrier rib height variation using ray-optics code incorporated with three-dimensional plasma simulation to analyze the effects of cell geometry for varying pressure conditions. The optimal barrier rib height decreased as the Xe partial pressure increased which resulted in due to the formation of local, strong sheath under high Xe partial pressure condition.

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학령기 어린이의 상지동작에 관한 인간공학적 연구 (A Biotechnological Study on the Sleeve Form Variation according to Arm Movements for Elementary Schoolgirls)

  • 이숙녀
    • 한국의류학회지
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    • 제10권3호
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    • pp.17-25
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    • 1986
  • The objectives of this study are to investigate the variation of the sleeve form by changing arm movements and to study the relationship among the three aspects of sleeve (sleeve height, width and armhole girth) by changing arm movements. Plasrun gyps were used for this experimental research. The subjects of this study were elementary schoolgirls (9$\~$12 years old). Arm mevements were 4 types($0^{\circ},\;45^{\circ},\;90^{\circ},\;135^{\circ}$) to the vertical directions. The statistical methods used to analyze the data included mean, standard deviation, the Pearson's correlation coefficients and coefficients of determination. The results obtained from this study were as follows; 1. According to the arm movements, the sleeve form changed more in the front than in the back. 2. As the arm movements were increased vertically, the heights of sleeves and the girths of the armholes were decreased, and the widths of sleeves were increased. 3. Variation rates by changing arm movements were different according to the variation of arm movement, and were the highest in sleeve height. 4. There was a negative correlation between sleeve height and width, and a positive correlation between sleeve height and armhole girth.

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在來種마늘의 量的形質에 대한 遺傳變異와 相關 (Genitic Variability and Correlation of Quantitative Characters in Local Garlic Cultivars)

  • 김정선
    • 한국자원식물학회지
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    • 제11권3호
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    • pp.264-271
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    • 1998
  • This study was conducted to investigate morphological characteristics of Korean local garlic varieties and to define the genetic variability and the correlations amongthe characters associated with yield. The plant height, the leaf sheath diameter, the nubmer of leaves, and bulb weight were significantly increased in the garlic plants from heavier seed bulbs. The proportation of six clove bulbs was more than 60% in Seosan variety and this was not realted with the number of cloves in seed bulb. While more than 70% bulbs in Jeoksung and Danyang varieties cultivated in paddy field were composed of 6 or 7 cloves, majority of the bulbs of Euisung and Danyang varieties cultivated in upland were composed of bulbs with 7 cloves or more. The highest genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were observed in bulb weight. GCV and PCV also showed high value in leaf sheath diameter. Thus, there is a greater scope for selection of these characters. The small difference between PCV and GCV values in plant height indicates that the environmental influence would be limited in this character. High heritability was observed of plant height (56.76%) and bulb weight (45.95%). And the weight per bulb (34.24%) exhibited highest genitic advance followed by leaf sheath diameter (18.8%) and plant height (9.61%), and those would be the ideal characters for selelction.

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