• 제목/요약/키워드: Single and Double

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확률론에 의환 Double Surface와 Single Surface 구성모델의 변형을 예측 정도의 평가 (Probabilistic Evaluation on Prediction Accuracy of the Strains by Double Surface and Single Surface Constitutive Model)

  • 정진섭;송용선;김찬기
    • 대한토목학회논문집
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    • 제14권1호
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    • pp.217-229
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    • 1994
  • Lade의 Double surface와 Single surface 구성모델의 변형을 예측의 정도를 비교평가하기 위하여 백마강모래로 두 구성식의 토질매개변수를 다수 구하고 각 변수의 통계치를 분석하였다. 이 통계치를 이용하여 일반함수의 변동계수를 산정하는 1계근사법으로 두 구성모델의 변형율에 대한 변동계수를 해석하였다. 그 결과 각 토질매개변수의 결정에는 Single surface 구성모델의 변수가 Double surface 구성모델의 변수보다 변동계수가 작게 나타나므로 매개변수결정에 일관성이 있는 반면 확률론으로 해석한 축 변형율의 변동계수는 Double surface 구성모텔에서 안정된 값을 나타내고 있으며, 체적 변형율에서는 두 구성모델 모두 안정된 해석결과를 보인다. 이는 두 구성모델의 특성을 비교한 다른 연구 결과와 일치하는 경향으로서 확률론에 의한 구성식의 평가가 효과적인 수단임을 알 수 있었다.

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이중범프포일 공기베어링의 성능에 미치는 마찰효과 (Friction Effects on the Performance of Double-Bumped Air Foil Bearings)

  • 김영철;이동현;김경웅
    • Tribology and Lubricants
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    • 제23권4호
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    • pp.162-169
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    • 2007
  • This paper deals with friction effects on the performance of double-bumped AFBs. The stiffness and damping coefficients of the double bump vary depending on the external load and its friction coefficient. The double bump can be either in the single or double active region depending on vertical deflection. The equivalent stiffness and damping coefficients of the bump system are derived from the vertical and horizontal deflection of the bump, including the friction effect. A static and dynamic performance analysis is carried out by using the finite difference method and the perturbation technique. The results of the performance analysis for a double-bumped AFB are compared with those obtained for a single-bumped AFB. This paper successfully proves that a double bumped AFB has higher load capacity, stiffness, and damping than a single-bumped AFB in a heavily loaded condition.

Double Sampling with Zero Acceptance Number for the First Sample

  • Bai, Do-Sun
    • 대한산업공학회지
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    • 제3권2호
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    • pp.99-106
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    • 1977
  • A double sampling procedure with zero acceptance number for the first sample whose operating characteristic closely matches that of a given single sampling plan and whose combined sample size does not exceed that of the given single sampling plan is proposed. The proposed double sampling plans corresponding to the MIL-STD-105D plans are tabulated and it is found that their ASN's are considerably smaller than those of corresponding MIL-STD-105D single or double sampling plans.

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Improvement of Electrochemical Performance of Lithium-ion Secondary Batteries using Double-Layered Thick Cathode Electrodes

  • Phiri, Isheunesu;Kim, Jeong-Tae;Kennedy, Ssendagire;Ravi, Muchakayala;Lee, Yong Min;Ryou, Myung-Hyun
    • 전기화학회지
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    • 제25권1호
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    • pp.32-41
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    • 2022
  • Various steps in the electrode production process, such as slurry mixing, slurry coating, drying, and calendaring, directly affect the quality and, consequently, mechanical properties and electrochemical performance of electrodes. Herein, a new method of slurry coating is developed: Double-coated electrode. Contrary to single-coated electrode, the cathode is prepared by double coating, wherein each coat is of half the total loading mass of the single-coated electrode. Each coat is dried and calendared. It is found that the double-coated electrode possesses more uniform pore distribution and higher electrode density and allows lesser extent of particle segregation than the single-coated electrode. Consequently, the double-coated electrode exhibits higher adhesion strength (74.7 N m-1) than the single-coated electrode (57.8 N m-1). Moreover, the double-coated electrode exhibits lower electric resistance (0.152 Ω cm-2) than the single-coated electrode (0.177 Ω cm-2). Compared to the single-coated electrode, the double-coated electrode displays higher electrochemical performance by exhibiting better rate capability, especially at higher C rates, and higher long-term cycling performance. Despite its simplicity, the proposed method allows effective electrode preparation by facilitating high electrochemical performance and is applicable for the large-scale production of high-energy-density electrodes.

횡족근 관절의 단일 및 이중 유합술의 비교 (Comparison of Single and Double Fusions in Transverse Tarsal Joint)

  • 윤현국;이종석;이진우
    • 대한족부족관절학회지
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    • 제15권1호
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    • pp.1-6
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    • 2011
  • Purpose: The purpose of this study was to compare the clinical and radiological results of single and double fusions in the transverse tarsal joint. Materials and Methods: Between December 2000 and April 2009, 16 patients (16 feet) who had been treated by fusion of transverse tarsal joint were included in this study. In 8 patients, only talonavicular joint was fused and in the other 8 patients, both talonavicular and calcaneocuboid joints were fused simultaneously. We have measured talo-first metatarsal angle, calcaneal pitch angle, talonavicular coverage angle and presence of adjacent joint arthritis for radiological assessment at both preoperative and last visit. Furthermore, we have evaluated Visual Analogue Scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) score and patient's satisfaction. Results: In a single fusion group, VAS was improved from $6.4{\pm}1.4$ to $0.8{\pm}1.0$ (p=0.0011) and AOFAS score was improved from $63.8{\pm}6.2$ to $89.4{\pm}9.8$ (p=0.0012). In a double fusion group, VAS was improved from $8.0{\pm}0.75$ to $2.0{\pm}1.8$ (p=0.0011) and AOFAS score was improved from $60.5{\pm}11.2$ to $89.5{\pm}6.0$ (p=0.0012). In the difference of talo-first metatarsal angle between two groups, a single fused group was more improved than a double fused group (p=0.04). Conclusion: Both single and double fusions are useful and attractive treatment for the transverse tarsal joint arthritis. Furthermore, a single fusion has advantages of less invasiveness and preserving some degree of hindfoot motion and could be an effective alternative to a double fusion if patient meets appropriate criteria through careful preoperative evaluation.

단삼음(丹蔘飮)이 고지혈증(高脂血症)에 미치는 영향(影響) (The Experimental Study on the Effects of Dansamyeum on Hyperlipidemia)

  • 김병철;박치상;박창국;이은주
    • 대한한방내과학회지
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    • 제21권1호
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    • pp.126-134
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    • 2000
  • Objectives : In order to study effects of Dansamyeum on Hyperlipidemia which causes Hypertension, Arteriosclerosis, Cerebral vascular disease and Ischemic heart disease Methods : The changes of serum total lipid, triglyceride, total cholesterol, HDL-cholesterol, LDL-cholesterol, body weight and organ weight were observed after the liquid extracts of Single-dosage Dansamyeum and Double-dosage Dansamyeum were administered p.o to the Hyperlipidemic rats induced by 1% cholesterol diet for 10, 20 and 30 days. Results : The body weight was significantly decreased in Double-dosage Dansamyeum group for 20 and 30 days compared with control group. The contents of total lipid were significantly decreased in Single-dosage Dansamyeum group for 20 days, but Double-dosage Dansamyeum group did not show any significant change compared with control group. The contents of total cholesterol were significantly decreased in Single-dosage Dansamyeum group for 20 days, and Double-dosage Dansamyeum group showed significant changes for 10 and 20 days compared with control group. The contents of triglyceride were significantly decreased in Single-dosage Dansamyeum group for 30 days, and Double-dosage Dansamyeum group showed significant changes for 10 days compared with control group. The contents of HDL-cholesterol were significantly increased in Single-dosage Dansamyeum group and Double-dosage Dansamyeum group for 10 days compared with control group. The contents of LDL-cholesterol were significantly decreased in Single-dosage Dansamyeum group for 10, 20 and 30 days, and Double-dosage Dansamyeum group showed significant changes for 10, 20 and 30 days compared with control group. The liver weight was significantly decreased in Single-dosage Dansamyeum group and Double-dosage Dansamyeum group compared with control group. The kidney and testis weight was significantly decreased in Single-dosage Dansamyeum group compared with control group. The spleen weight was significantly decreased in Double-dosage Dansamyeum group compared with control group. Conclusions : It was thought that Single-dosage Dansamyeum and Double-dosage Dansamyeum could be applied effectively to the Hyperlipidemia.

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A Comparison of the Characteristics between Single and Double Finger Gestures for Web Browsers

  • Park, Jae-Kyu;Lim, Young-Jae;Jung, Eui-S.
    • 대한인간공학회지
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    • 제31권5호
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    • pp.629-636
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    • 2012
  • Objective: The purpose of this study is to compare the characteristics of single and double finger gestures related on the web browser and to extract the appropriate finger gestures. Background: As electronic equipment emphasizes miniaturization for improving portability various interfaces are being developed as input devices. Electronic devices are made smaller, the gesture recognition technology using the touch-based interface is favored for easy editing. In addition, user focus primarily on the simplicity of intuitive interfaces which propels further research of gesture based interfaces. In particular, the fingers in these intuitive interfaces are simple and fast which are users friendly. Recently, the single and double finger gestures are becoming more popular so more applications for these gestures are being developed. However, systems and software that employ such finger gesture lack consistency in addition to having unclear standard and guideline development. Method: In order to learn the application of these gestures, we performed the sketch map method which happens to be a method for memory elicitation. In addition, we used the MIMA(Meaning in Mediated Action) method to evaluate gesture interface. Results: This study created appropriate gestures for intuitive judgment. We conducted a usability test which consisted of single and double finger gestures. The results showed that double finger gestures had less performance time faster than single finger gestures. Single finger gestures are a wide satisfaction difference between similar type and difference type. That is, single finger gestures can judge intuitively in a similar type but it is difficult to associate functions in difference type. Conclusion: This study was found that double finger gesture was effective to associate functions for web navigations. Especially, this double finger gesture could be effective on associating complex forms such as curve shaped gestures. Application: This study aimed to facilitate the design products which utilized finger and hand gestures.

Double curing unit system을 이용한 복합 레진의 광중합 수축에 관한 연구 (POLYMERIZATION SHRINKAGE OF COMPOSITE RESIN USING DOUBLE CURING UNIT SYSTEM)

  • 한미란;김종수;유승훈
    • 대한소아치과학회지
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    • 제36권2호
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    • pp.189-198
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    • 2009
  • 본 연구는 복합 레진이 광원을 향해 수축이 일어난다는 점에 착안하여 중합 수축시 필연적으로 발생되는 치질과의 결합단절을 개선하고자 double light emitting diode(LED) system을 고안하였으며, 중합 수축 시 발생하는 스트레인의 변화를 기록하고 미세 누출의 양상을 관찰하여 비교 분석한 결과 다음과 같은 결론을 얻었다. 1. 스트레인의 변화를 살펴보면, single LED system과 double LED system에서 광중합 개시와 함께 급격히 증가하였다가 시간이 지남에 따라 서서히 감소하는 유사한 수축 응력 양상을 보였다. 2. 최대 응력의 발생과 유지는 double LED system보다 single LED system에서 더 높게 나타났다(p<0.05). 3. Double LED system이 single LED system보다 미세 누출이 더 낮게 나타났다(p<0.05). 이상의 결과를 종합해보면, single LED system에 비해 double LED system에서 중합 수축 응력이 크지 않고 미세 누출도 줄일 수 있어 임상에서 매우 유용한 장비로 사용될 수 있으리라 생각된다. 그러나 두 개의 광원이 구강내에서 원활하게 움직이기 위해서는 광원의 크기가 충분히 작아야 한다. 현재 개발된 LED는 광량이 충분하지 않아 시술 시간의 단축을 원하는 소아 환자의 접착 수복에서는 어려운 실정이다. 따라서 수복물의 완전한 중합과 중합 시간의 감소를 위해 더 높은 출력의 광원이 필요하고, 이는 LED광원의 발달에 기대해 볼 수 있으리라 사료된다.

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Comparison of inclination and vertical changes between single-wire and double-wire retraction techniques in lingual orthodontics

  • Hung, Bui Quang;Hong, Mihee;Yu, Wonjae;Kyung, Hee-Moon
    • 대한치과교정학회지
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    • 제50권1호
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    • pp.26-32
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    • 2020
  • Objective: The Heat Induction Typodont System (HITS), used in some recent studies, has a distinct advantage over previous tooth movement simulation methods. This study aimed to compare inclination and vertical changes between the single-wire and double-wire techniques during en masse retraction with different lengths of lever arms in lingual orthodontics using an upgraded version of the HITS. Methods: Duet lingual brackets, which have two main slots, were used in this study. Forty samples were divided into four groups according to the length of the lever arm (3-mm or 6-mm hook) and the retraction wire (single-wire or double-wire). Four millimeters of en masse retraction was performed using lingual appliances. Thereafter, 3-dimensional-scanned images of the typodont were analyzed to measure inclination and vertical changes of the anterior teeth. Results: Incisor inclination presented more changes in the single-wire groups than in the double-wire groups. However, canine inclination did not differ between these groups. Regarding vertical changes, only the lateral incisors in the single-wire groups presented significantly larger values than did those in the double-wire groups. Combining the effect of hook lengths, among the four groups, the single-wire group with the 3-mm hook had the highest value, while the double-wire group with the 6-mm hook showed the least decrease in crown inclination and extrusion. Conclusions: The double-wire technique with an extended lever arm provided advantages over the single-wire technique with the same lever arm length in preventing torque loss and extrusion of the anterior teeth during en masse retraction in lingual orthodontics.

대시호탕가미방(大柴胡湯加味方)이 고혈압(高血壓) 및 고지혈증(高脂血症)에 미치는 영향(影響) (A Experimental Study on the Effect of Kami-Daesihotang on Hyperlipidemia & Hypertension)

  • 박치상;박창국;한승동;박순달
    • 대한한방내과학회지
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    • 제19권2호
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    • pp.159-184
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    • 1998
  • The aim of the study was the experiment of the effect that Kami-Daesihotang had on the essential hypertension and hyperlipidemia. Rats were orally administered with Kami-Daesihotang for 30days and the constituent of the plasma and serum were analysed at the 10th, 20th and 30th day from the first day of experiment, respectively. The heart rate, blood pressure, plasma renin activity, plasma level of aldosterone, catecholamine, sodium and angiotensin II were measured after an oral administration of Kami-Daesihotang in SHR. In addition, serum levels of total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol and total lipid were measured with cholesterol-fed rats. The results were summarized as following ; 1. Single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang remarkably decreased the blood pressure in SHR. 2. Double-dosage Kami-Daesihotang were recognized as having the effect on the decreased of the pulse rate in SHR. 3. Plasma renin activity was significantly decreasd in SHR after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 4. Double-dosage Kami-Daesihotang considerably reduced the plasma angiotensin level in SHR. 5. Noticeable decreased of plasma norepinephrine level was showed in SHR, after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 6. Single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang noticeable reduced body weight in hyperlipidemia rats which had fed with 1% cholesterol. 7. Single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang had a significantly decreasing effect on serum total cholesterol in hyperlipidemia rats which had fed with 1% cholesterol. 8. Serum triglyceride level was importantly decreased in hyperlipidemia rats which had fed with 1% cholesterol, after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 9. Remarkable decreased of serum low density lipoprotein cholesterol level was found in hyperlipidemia rats which had fed with 1% cholesterol, after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 10. Double-dosage Kami-Daesihotang was showed a significantly decreasing effect on serum total lipid level in hyperlipidemia rats which had fed with 1% cholesterol. 11. Single-dosage Kami-Daesihotang noticeably reduced organ weight of liver, kidney, spleen and testis in hyperlipidemia rats which had fed with 1% cholesterol. Double-dosage Kami-Daesihotang significantly decreased organ weight of liver, kidney and spleen in hyperlipidemia rats. These Findings suggest a possible anti-hypertensive and hyperlipidemic effect of Kami-Daesihotang.

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