• 제목/요약/키워드: Thickness change

검색결과 2,316건 처리시간 0.03초

원사의 수축에 따른 다공성 편성물의 형태변화와 열·수분 전달특성 (The appearance change and heat·moisture transfer properties of knitted fabric by yarn shrinkage)

  • 상정선;박주현;이미식;오경화
    • 복식문화연구
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    • 제25권6호
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    • pp.880-892
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    • 2017
  • In this study, the appearance change and the heat moisture transfer properties of knitted fabric by yarn shrinkage were examined to obtain useful data on the development of thermo-sensitive functional materials. Eleven types of knitted fabric were knitted using highly bulky acrylic-blended yarn. After shrinking the specimens using dry heat treatment, the appearance change and thickness were measured. An HEC simulator was adopted for measuring the heat moisture transfer properties of specimens by yarn shrinkage. When holes were arranged vertically in the mesh structure, the specimens with 2,500 and 5,000 holes showed high percent change of hole area, appearance, and thickness. When holes were diagonally arranged in the mesh structure, the percent change of hole area in the specimen with 1,250 holes was larger than the one with 2,500 holes. However, the dimensional stability of the specimen with 2,500 holes was better because of its smaller appearance and thickness change. In the tuck structure, the percent change of hole area in the specimen with 625 and 416 holes was relatively large compared with the appearance and thickness change. Furthermore, the hole size in the tuck structure was smaller than that in the mesh structure but the percent change of hole area was larger. Therefore, it was proved that the tuck structure is more suitable than the mesh structure for developing thermo-sensitive functional materials. Heat moisture transfer property test verified that the change of hole area by yarn shrinkage enabled obtaining the thermal effect due to the distinct temperature difference in the inner layer.

열간압연 공정 해석용 시뮬레이터의 개발과 응용(II) (Development of Hot Rolling Process Analysis Simulator and Its Application(II))

  • 이원호;이상룡
    • 소성∙가공
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    • 제8권1호
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    • pp.78-91
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    • 1999
  • The endless hot rolling has been focused as an innovative process technology for increasing the productivity drastically and reducing the imperfection of quality in hot rolled steel strip. To realize it in actual mill, a lots of new facilities such as bar coiler, movable LASER welder and high speed strip shear should be equipped. And also it is necessary to develop the control technique for changing the roll gap and rolling speed during rolling, which is named as Flying Gap and Speed Change control technology. To prevent a strip rupture caused by excessive tension, it is very important to minimize fluctuations in strip thickness and intension during FGSC control. In this paper, the mathematical model for FGSC control algorithm was suggested and dynamic simulation is performed to accertain the effect of suggested control method on fluctuations in strip thickness and tension. For endless hot rolling simulation, a lots of FGSC control situations, for instance - strip thickness change from strip to strip - strip width change from strip to strip - carbon content change from strip to strip are considered.

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Digital subtraction radiography를 이용한 치조골 변화의 정략적 분석 (QUANTITATIVE ANALYSIS OF THE ALVEOLAR BONE CHANGE BY THE DIGITAL SUBTRACTION RADIOGRAPHY)

  • 류명걸;정현주
    • Journal of Periodontal and Implant Science
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    • 제25권1호
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    • pp.67-75
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    • 1995
  • The progress of periodontal disease and the wound healing process after treatment result in alveolar bone bone change. So, detection of it is very important in the diagnosis and the radiograph of periodontal disease. Various effects have been made to assess the subtle alveolar bone change and digital subtraction radiography (DSR) has been reported to be the best method in evaluating it qualitatively and quantitatively. The present study was performed to estimate the detectable alveolar bone change qualitatively with digital subtraction radiography. For the in vitro study, 10 intraoral standard radiographs were taken from porcine dry mandible which a rectangular cortical bone chip of 0.1mm to 1.0mm thickness with 0.1mm increment was attached on the buccal surface. The radiographs without and with bone plates were reviewed at the same time by 10 observers and requested to detect the presence of cortical bone plates. Digital Subtraction radiograph was reviewed subsequently by using the DSR system(digital converter-256 grey-levels,DT 2851,Data Translation Co., U.S.A;IBM 386 ; CCD camera, FOTOVIX, Tamrom Co., Japan). The detectable thickness of cortical bone plate was O.4mm on the intraoral radiograph and 0.2mm on the subtaction images. For the human study, radiographs were taken from patients by using intraoral film holding device and aluminum reference wedge before and 3 month after bone graft and 1 week after osteoplasty. The grey level change was estimated in the subtraction images and calculated to aluminum equivalent thickness. The grey level of the grafted site was higher that that of healthy controls. Average grey levels of change on healthy controls were O.48mm aluminum equivalent. However, the amount of changes in grafted sites were 1.87mm aluminum thickness equivalent and in the site of osteoplasty were -1.49mm aluminum thickness equivalent. In conclusion, digital subtraction radiography was more effective in detecting as subtle change of alveolar bone than intraoral standard radiography. With the aid of quantitative analysis of digital subtraction radiography, alveolar bone resorption of apposition can be estimated during diagnosis and treatment of periodontally diseased patients.

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어깨뼈 뒤 당김 운동 방법에 따른 큰마름근과 중간등세모근의 근두께비의 비교 (Comparison of the Ratio of Thicknesses of the Rhomboid Major and Middle Trapezius Muscles While Performing Scapular Retraction Exercises)

  • 박헌미;김선엽
    • 한국전문물리치료학회지
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    • 제29권2호
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    • pp.131-139
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    • 2022
  • Background: Shoulder impingement syndrome, a major cause of shoulder pain, involves weakness of the scapular retractor muscles. The major scapular retractor muscles are the middle trapezius and rhomboid major muscles; however, the latter is excluded in most studies. Objects: We aimed to measure the thickness of the middle trapezius and rhomboid major muscles using an ultrasonic diagnostic imaging system while performing four different shoulder retraction exercises and comparing the thicknesses and ratio of the thicknesses of these muscles. Methods: The thickness of the middle trapezius and rhomboid major muscles was measured in 24 healthy adults using ultrasound. Muscle thickness was measured three times in the Reference posture and four times while performing four different exercises that involved scapular retraction. The averages and standard deviations of the measured muscle thicknesses were obtained and compared. The ratio of muscle thickness and rate of changes in muscle thickness between the reference posture and the four exercises were compared. Results: For both, male (n = 10) and female (n = 14), there was a significant difference in the thickness of the middle trapezius muscle between the reference posture and the four exercises (p < 0.05) and in the thickness of the middle trapezius and rhomboid major muscles between male and female (p < 0.05); however, there was no significant difference in the ratio of the thicknesses of these muscles. Although a significant difference in the rate of change in muscle thickness during the four exercises was noted, there was no significant difference in the ratio of change in muscle thickness. Conclusion: This study demonstrates the ratio of the thicknesses of the middle trapezius and rhomboid major muscles and the rate of change in their thickness during exercises involving scapular retraction in healthy people in their 20s-30s.

고관절 내전근 수축이 복횡근의 두께변화에 미치는 영향 (The Effect of Change in Transversus Abdominis Thickness Using Ultrasound Image during a Hip Adductor Contraction)

  • 문현주;구봉오
    • 대한물리의학회지
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    • 제6권3호
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    • pp.287-292
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    • 2011
  • Purpose :The present study invesigated the effect of changes in transversus abdominis thickness using ultrasonography during a hip adductor contraction. Methods : This study was carred out in a volunteer sample of adults (N=30) without a history of low back pain or injury. In standing position, muscle thickness measurements of transversus abdominis(TrA) were measured using ultrasonography at rest and during a hip adducor contraction. Results : TrA thickness were influenced a hip adductor during a voluntary contraction in people without LBP. TrA showed significantly greater thickness changes on a hip adductor contraction.(p=0.000) Conclusion : The results from this study showed that the hip adductor contraction improves the ability to increase change in TrA thickness. These results can be a good evidence to prevent low back pain due to hip adductor weakness or genu varum deformity of knee osteoarthritis.

스크린 인쇄 기법에 의해 제작된 분산형 무기 EL 램프의 형광층 및 유전층의 두께 변화 (The Thickness Change of the Phosphor Ink Layer and the Dielectric Ink Layer of a Inorganic Powder EL Lamp That was produced by Screen Printing Technique)

  • 문길환;강영립
    • 한국인쇄학회지
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    • 제29권2호
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    • pp.83-92
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    • 2011
  • A inorganic powder EL lamp was made by screen printing technique with phosphor ink and dielectric ink. The thickness change of a phosphor ink layer and a dielectric ink layer were not influenced on dielectric content, but rely on phosphor size and vehicle. Once finishing screen printing technique with phosphor ink and dielectric ink, and its surface has been printed again before not drying of phosphor ink and dielectric ink. Then phosphor ink and dielectric ink were not transferred. The electric capacity of inorganic powder EL lamp was more influenced on dielectric content than the thickness of dielectric ink layer, and it was more dependent on the thickness of phosphor ink layer than the thickness of dielectric ink layer.

Clasp arm의 형상과 재료 탄성에 따른 단위 변위에 대한 힘 (Force per unit Displacement according to the Shape of a Clasp Arm and Flexibility of the Material)

  • 임동천
    • 대한치과기공학회지
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    • 제23권2호
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    • pp.171-177
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    • 2002
  • The purpose of this study is to evaluate force per unit displacements according to the shape of a clasp arm and flexibility of the material. Effect of four shape parameters of a clasp, base width and thickness and tip width and thickness, on tip displacement and force per unit displacement was investigated to get the fact that displacement and force per unit displacement at the tip increase as thickness and width of clasp arm increase just as expected. But force per unit displacement is much more affected by the change in thickness than by change in width. So it is effective to increase the thickness rather than width in order to increase the force at the tip using the same amount of the material.

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지지면 차이에 따른 월 스쿼트 운동이 몸통 근두께와 균형에 미치는 영향 (The effect of wall squat exercise according to the difference in the support surface on the muscle thickness and balance of the trunk)

  • 정진규;박재철
    • 대한물리치료과학회지
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    • 제29권1호
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    • pp.64-72
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    • 2022
  • Background: The purpose of this study is to investigate the effect of wall squat exercise according to the difference in the support surface on the thickness change of external oblique, internal oblique and transverse abdominalis of the trunk muscles and the change in distance of center of pressure when the eyes are opened and closed. Design: Randomized controlled trial. Methods: The subjects were 26 healthy adults, 18 males and 8 females. The composition of each group using the single-blind method was 13 people in the unstable side wall squat exercise group and 13 people in the stable side wall squat exercise group. Experimental measurements were divided into before, 3 weeks, and 6 weeks after the experiment, and changes in muscle thickness and balance were confirmed. Muscle thickness was measured using ultrasinic, and static balance change was measured using Bio-rescue. Results: There were significant differences in the thickness changes of external oblique, internal oblique and transverse abdominalis according to the wall squat exercise method by period and in the interaction between the period and the group (p<0.05). As a result of the post-hoc analysis, there was a significant difference in the change between the two groups in external oblique muscle after 6 weeks. And there was a significant difference in the distance of the pressure center between eyes open and closed eyes (p<0.05). Conclusion: In terms of instability, wall squat exercise was positive for changes in trunk muscle thickness. It suggests the possibility of using it for trunk muscle strengthening training in the future.

The Effect of Exercise Using Grasping on Shoulder Muscle Activity and Muscle Thickness of Patients with Rotator Cuff Repair

  • Choi, Eun-Young;Choi, Hyun
    • The Journal of Korean Physical Therapy
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    • 제28권1호
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    • pp.52-58
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    • 2016
  • Purpose: This study intended to mediate shoulder exercise using grasping and investigate examine how its effects on affects activities of the shoulder surrounding muscles of the shoulder and thickness of shoulder muscle to suggest effective exercise for patients with rotator cuff repair to return to daily life. Methods: This study has been done targeteding male patients more than 6 weeks after having En-masse Suture Bridge Technique as rotator cuff repair of the right shoulder, aged 40 to 55 in a medical institution located in Jeollanam-do. Experimental group I (n=15) was selected for a conducting common exercise therapy program and Experimental group II (n=15) was selected for an conducting exercise therapy program using grasping. %RVC was measured by surface electromyography and muscle thickness was measured by ultrasound before mediation to for analysisze of before and after results within group and between groups. Results: In comparison of change of %RVC, Tthere were meaningful differences in only posterior deltoid and infraspinatus in comparing a change of %RVC within experimental group I (p<0.001),. and Tthere were meaningful differences in both supraspinatus and infraspinatus in muscle thickness within experimental group I (p<0.001). In comparison of change of %RVC, Tthere were meaningful differences in anterior deltoid, posterior deltoid and infraspinatus in comparing a change of %RVC within experimental group II (p<0.05)(p<0.01) (p<0.001), and there were meaningful differences in both supraspinatus and infraspinatus in muscle thickness within experimental group II (p<0.001). In comparison of change of %RVC between groups, Tthere was a meaningful difference in only posterior deltoid in comparing a change of %RVC between groups (p<0.001). Conclusion: We found that exercise therapy using grasping has a positive effect on shoulder stability muscles such as supraspinatus muscle and infraspinatus muscle and activity of deltoid muscle.

하이드로겔 렌즈와 실리콘-하이드로겔 렌즈가 각막 두께에 미치는 영향 (Effect of Hydrogel lens and Silicone-Hydrogel lens on Corneal thickness)

  • 서정익
    • 한국임상보건과학회지
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    • 제5권4호
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    • pp.1021-1025
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    • 2017
  • Purpose: Changes in corneal thickness after wearing hydrogel lens and silicone-hydrogel lens with different oxygen transmission rates wew syudied. Methods: Experiments were performed on 11 subjects(22 eyes). corneal thickness was measured after wearing contact lenses for 8 hours. Corneal thickness was measured using ORB Scan II(ver. 3.14) Results: In the results of the corneal thickness measurement by direction, in the case of the hydrogel-tor lens, the center thickness was $33.63{\mu}m$, the nasal was $34.29{\mu}m$, the temporal was $27.17{\mu}m$, the inferior was $27.17{\mu}m$, the superior was $18.90{\mu}m$, and change rates were 6.28%, 5.71%, 5.40%, 4.75% and 3.09%, respectively. In the results of the corneal thickness measurement by diameter, in the case of the hydrogel-tor lens, the center was $33.63{\mu}m$, the mid-peripheral was $28.19{\mu}m$, the peripheral was $24.18{\mu}m$, and change rates were 6.28%, 4.76%, and 3.79%, respectively. Conclusions: The hydrogel lenses with relatively low oxygen transmission rates resulted in a significant increase in thickness over the entire cornea compared to silicon-hydrogel lenses with high oxygen transmission rates.