• 제목/요약/키워드: interrupted

검색결과 705건 처리시간 0.069초

고온단속변형량이 단상 Cu-Zn합금의 정적연화에 미치는 영향 (Effect of Hot Interrupted strain on Static Softening of Single Phase Cu-Zn Alloy)

  • 권용환;조상현;유연철
    • 소성∙가공
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    • 제4권2호
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    • pp.169-179
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    • 1995
  • Static restoration mechanism during hot interrupted deformation of Cu-Zn alloy was studied in the temperature range from $550^{\circ}C$ to $750^{\circ}C$ and at a constant strain rate of 0.1/sec. At a given temperature, the hot interrupted deformations were performed with variation of interrupted time $t_i$ form 1 to 50 sec and of interrupted strain ${\varepsilon}_i$ from 0.15 to 0.90. From the analysis of the values of the critical strain of ${\varepsilon}_c$ for tje initiation of dynamic recrystallization and the peak strain of${\varepsilon}_p$, the relationship ${\varepsilon}_c{\fallingdotseq}0.7{\varepsilon}_p$ was obtained. It was clarified that the softening of the interrupted deformation was mainly the static recrystallization and the fractional softening(FS) which was over 30% mostly confirmed this result. The fractional softening of the interrupted time $t_i$ especially and pre-strain. The FS increased with increasing strain rate, interrupted time and pre-strain. The change of microstructures after hot deformation could be predicted by the FS. when the FS was 30~100%, static recrystallization was happened and grain growth was observed at the condition which was $750^{\circ}C$ deformation temperature, 0.45 prestrain and this condition's FS value was over 100%.

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테이프와 거칠기가 설치된 사각 채널의 압력강하 특성 (Characteristics of Pressure Drops in Square Channels with Twisted Tape Inserts plus Axial Interrupted Ribs)

  • 안수환;배성택;강호근
    • 동력기계공학회지
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    • 제10권4호
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    • pp.38-42
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    • 2006
  • Pressure drops and friction factors in square channels with twisted tape inserts plus axial interrupted ribs are investigated. Tests are performed for Reynolds numbers ranging from 8,900 to 29,000. The rib height-to-channel hydraulic diameter, $e/D_h$, is kept at 0.057 and test section length-to-hydraulic diameter, $L/D_h$ is 30. The pressure drops and friction factor values are enhanced with axial interrupted ribs and twisted tape inserts. Square channels with twisted tape inserts plus axial interrupted ribs show the greatest pressure loss penalty in the present work. Friction factor data obtained for the square channel with twisted tape inserts plus axial interrupted ribs are less than those in the past publications for circular tubes with axial interrupted ribs and twisted tape inserts.

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양극 경두개직류자극에 의한 운동관련피질전위의 변화 (Change of Cerebral Motor Area Activity by Anodal Transcranial Direct Current Stimulation (tDCS))

  • 임영은;김수현;양대중;김태열
    • The Journal of Korean Physical Therapy
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    • 제21권4호
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    • pp.65-71
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    • 2009
  • Purpose: Transcranial direct current stimulation (tDCS) is a useful method for modulating the brain activity. This study compared the effect of continuous and interrupted tDCS using the change in the movement related cortical potential. Methods: Thirty healthy participants (male: 18 and female: 12) were assigned randomly to three groups; sham tDCS, continuous tDCS, which the current continuously flowed for 10 minutes, and interrupted tDCS, which the interrupted current flowed for 10 minutes (repetition: 4sec stimulation and 5sec rest) at an intensity of 1mA with anodal polarity. The effect of tDCS on the right primary motor area was measured from the movement related cortical potential (MRCP) before and after the experiment. MRCP consisted of the bereitshaftspotential (BP) and negative slope potential (NS) at Cz and C4. Results: Continuous and interrupted tDCS showed a significant difference in the changes in the BP, NS at Cz and C4 compared to the sham tDCS. However, there was no significant difference between the continuous tDCS and interrupted tDCS. Conclusion: The change in cortical activity by continuous and interrupted tDCS results from an improvement in the MRCP. An interrupted tDCS may be a safe and useful modality for stimulating the cortical region.

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CNC선반에서 연속절삭 및 단속절삭시 공구손상에 대한 음향방출신호 특성 연구 (A Study on the Characteristics of AE Signals of Tool Failure for Continuous and Interrupted Cutting under CNC Lathe)

  • Kim, T.B.;Kang, S.Y.;Kim, W.I.;Lee, Y.K.
    • 한국정밀공학회지
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    • 제13권4호
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    • pp.136-142
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    • 1996
  • Automatic monitoring of cutting process is one of the most important technology in machining. AE sensing technology has been applied to monitoring process and proved to be effective in detecting tool abnor- malities such as tool wear and fracture. In this experimental study. AE signals were detected from the tool holder for continuous and interrupted cutting, which obtained from changing workpice material configuration, under control of constant cutting speed from CNC lathe. From statistical and frequency analysis, the AE signals were analyzed to obtaining the characteristics of continuous and interrupted cutting conditions and tool failure. The Kurtosis values decreased but RMS voltages increased as the cutting speed increased, in both continuous and interrupted cutting. RMS voltage is suddenly increased but Kurtosis value is suddenly decreased when tool failure condition. Power spectrum density of AE signals when tool failure reaches extreme value around 0.065 cycles/ .mu. m.

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직업 경력단절 기혼 여성에 대한 질적 연구: 30대 여성의 경력단절 이후의 삶을 중심으로 (A Qualitative Study on the Career-interrupted Lives of Career-Interrupted Women in their thirties)

  • 김수리;이수림;유정이
    • 가족자원경영과 정책
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    • 제19권2호
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    • pp.75-99
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    • 2015
  • The purpose of this study was to examine the career-interrupted lives of highly educated career-interrupted women. The participants were 11 women in their thirties who had graduated from university graduated and had a child. We collected the qualitative data using a focused group interview. The results of this study can be summarized as follows. First, in personal histories of the career-interrupted women, there were marriages and births, difficulties with child care, priority placed on the family, pressure to retire, and an absence of a layoff system related to births and child care. Second, with regard to their interrupted lives, while there was comfort and an absence of work-stress, there was child care stress, financial stress, anxiety due to career uncertainty, a loss of the social self, depression, emptiness, low self-esteem, dependence on husbands, regret, conflict in career choices, and envy of childcare support. Third, their reasons for seeking reemployment included the financial benefits, increased independence, self-realization in their job, hope for a stable job, self-management, and hope for a social network.

연속 봉합 단속 결찰법을 이용한 미세 혈관 문합법 (Microvascular Anastomosis Using 'Continuous Suture with Interrupted Knot' Technique)

  • 최문수;박상훈
    • Archives of Reconstructive Microsurgery
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    • 제8권1호
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    • pp.22-27
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    • 1999
  • While the conventional end-to-end anastomotic technique is accepted as 'the golden standard' for microvascular anastomosis, it is time-consuming and tedious. In an effort to offer faster and safer ways of performing microvascular anastomoses, numerous anastomotic techniques have been proposed, but further refinements in microvascular techniques are still necessary. A 'continuous suture with interrupted knot' technique was devised for faster and safer anastomosis. It has been successfully used in microanastomoses of both artery and vein for free tissue transfer. It is a combination of the interrupted suturing technique and the continuous suturing technique. First, a continuous suture is made with the size of loop decreasing in order, and then the sutures are tied individually from the first loop to the last one as in the conventional interrupted suturing technique. It was applied clinically to fourteen patients over the past ten months and found to be a highly efficient technique that satisfied our needs. This 'continuous suture with interrupted knot' technique has several advantages over other techniques : The operative time is reduced comparing conventional interrupted suture technique. By delaying the tie and with the vessel walls kept separated, the risk of through-stitch can be reduced. Tying all the sutures at one time not only speed up the procedures, but also reduced the surgeon's fatigue. In addition, it has no problem of anastomotic stenosis which is a disadvantage of continuous suture technique. This technique proved to be faster and safer, and has patency equal to that of the conventional end-to-end anastomosis. It is of great help to the surgeon in reducing operative time, especially in clinical situations when many anastomoses are required, or lengthy grafting procedures are undertaken.

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경력단절여성의 개인특성에 따른 재취업욕구 차이 분석 (Analysis of the Differences in Re-employment Need on the Individual Characteristic of Career Interrupted Woman)

  • 신연하;이동명
    • 한국콘텐츠학회논문지
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    • 제17권9호
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    • pp.310-323
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    • 2017
  • 본 연구는 경력단절여성의 개인특성에 따른 구직의사와 구직활동의 재취업욕구 차이를 분석하여 이들의 경제활동을 지원하는데 필요한 자료와 정보를 제공하고자 한다. 연구의 목적은 경력단절여성과 직업교육, 개인특성과 재취업욕구의 이론적 배경을 바탕으로 선행연구를 검토하고 실증분석 하였다. 경력단절여성 중 직업교육경험이 있는 자를 대상으로 실시한 150부의 설문자료를 분석하여, 일원변량분석과 T검증을 실시하였으며, SPSS 12.0v 프로그램을 사용하였다. 분석 결과, 개인특성에 따라 재취업욕구에 차이가 있으며, 구직의사와 구직활동에 차이가 있는 것으로 나타났다. 이와 같은 연구결과는 경력단절여성의 개인특성에 따라 재취업 방안을 제시 할 수 있다는 것을 시사한다. 따라서 본 연구에서는 경력단절여성의 개인특성을 고려한 맞춤형 교육과 제도개선이 필요하다는 점을 제안하였다.

경력단절 여성의 진로결정 자기효능감과 경력계획의 관계에서 결과기대의 매개효과 (The Mediating Effect of Outcome Expectation on the Relationship between the Career Decision-Making Self-Efficacy and the Career Planning of Career Interrupted Women)

  • 이수분;이정희
    • 직업교육연구
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    • 제36권2호
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    • pp.51-67
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    • 2017
  • 본 연구의 목적은 경력단절 여성의 진로결정 자기효능감과 경력계획의 관계에서 결과기대의 매개효과를 확인하고자 하는 것이다. 이러한 연구목적에 따라 부산 경남지역에 소재한 여성인력개발센터에서 직업교육과 상담에 참여하고 있고, 취업의사가 있는 경력단절 여성 270명을 대상으로 진로결정 자기효능감, 결과기대, 경력계획 척도를 활용하여 자료를 수집하였다. 그리고 수집된 자료는 회귀분석방법으로 매개효과를 분석하였으며, 이에 대한 연구결과는 다음과 같다. 첫째, 경력단절 여성의 진로결정 자기효능감, 결과기대, 경력계획은 정적상관이 있는 것으로 확인되었다. 둘째, 경력단절 여성의 진로결정 자기효능감과 경력계획의 관계에서 결과기대의 매개효과는 통계적으로 유의미한 것으로 확인되었다. 그리고 마지막으로 본 연구결과에 기초하여 연구의 의의와 경력단절 여성의 경력개발을 위한 교육적 제언을 하였다. 본 연구는 이후 경력단절 여성의 경력개발을 위한 교육 및 상담에 의미 있는 기초자료로 활용될 것으로 기대된다.

미세 혈관 접합술에서 봉합적 수기와 비봉합적 수기의 실험적 비교 연구 (Experimental Study of the Anastomosis with Suture vs Non-suture Techinique)

  • 정덕환;한정수;유명철;남기운;선승덕
    • Archives of Reconstructive Microsurgery
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    • 제3권1호
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    • pp.45-53
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    • 1994
  • Suture microvascular anastomosis is time-consuming and tedious and demands long and continuous training. Techinique of anastomosis of microvessel was presented interrupted suture and continuous suture. Recently the unilink instrument system is created as a fast and simple method to achieve high patency rates without long and continuous training in the anastomosis of small vessels. The author experimentally studied the femoral artery of 20 mice(0.5-1.0mm, av. 0.7mm), the femoral vein of 20 mice(0.8-1.6mm, av. 1.2mm) after anastomosis with interrupted suture in 20 cases and continuous sutre in 20 cases. For the unilink apparatus we used the carotid arteries of 15 cases in 14 rabbits(1.0-1.6mm, av. 1.3mm) and facial veins of 12 cases in 14 rabbits(0.9mm-2.2mm, av. 1.5mm). A total of 27 arterial and venous anastomoses were performed. We examined the postoperative patency at immediate, 2 weeks, and 8 weeks. The results were as followings, 1. In the arterial anastomosis the rate of patency was 90%(18/20) in interrupted suture, 90%(18/20) in continuous suture and 93%(13/15) in unilink apparatus. In the venous anastomosis the rate of patency was 90%(18/20) in interrupted suture, 80%(16/20) in continuous suture and 100%(9/9) in unilink apparatus. 2. The mean time for completion of the arterial anastomosis were 12.2 minutes in interrupted suture group, 10.3 minutes in continouous suture group and 8.5 minutes in unillnk apparatus group. The mean time for completion of the venous anastomosis were 13.6 minutes in interrupted suture group, 11.0 minutes in continuous suture group and 6.2 minutes in unilink apparatus group. 3. At the histological examination of suture group, hyperplastic reaction of middle layer and subintimal hyperplasia were observed. In unilink apparatus group, the endothelium layer was continued and the thickness of vessel wall was decreased due to moderate atrophy of the media and mild degree of nonspecific chronic inflammation were seen around the unilink apparatus. 4. No significants was noticied in foreign body reaction among the interrupted, continuous and unilink apparatus group. 5. A case of the arterial anastomosis was released with acting out at 15 minutes after operation. 6. The important factors in the technical problems were accurate apposition of the cut vessel edges in suture group and the proper selection of the ring size and optimal fitting between two rings in unilink apparatus group. Even though the outer diamater of vessel in suture group was different from that in unilink apparatus group the unilink method provides a very safe, fast, and simple way to perform microvascular anastomoses especially in anastomosis of vein. But howerver suture was needed in vessels below 1 mm outer diamater. In that situation continuous suture was benefit than the interrupted suture in operation time.

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초경피복공구를 이용한 기계구조용 탄소강의 단속절삭시 표면거칠기 예측 (Surface Roughness Prediction of Interrupted Cutting in SM45C Using Coated Tool)

  • 배명일;이이선
    • 한국기계가공학회지
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    • 제13권3호
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    • pp.77-82
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    • 2014
  • In this study, we carried out the interrupted cutting of carbon steel for a machine structure (SM45C) with a CVD-coated tool and conducted an ANOVA test and a confidence interval analysis to find factors influence the surface roughness and to obtain a regression equation. We found that factor which mostly affects the surface roughness during interrupted cutting was the feed rate. The cutting speed and depth of the cut only had small effect on the surface roughness. From the result of a multi-regression analysis during an interrupted cutting experiment, we obtained regression equation. Its coefficient of determination was 0.918, indicating that the regression equation was predictable. Compared to continuous cutting, if the feed rate increases, the surface roughness will also increase during interrupted cutting.