• Title/Summary/Keyword: TFO

Search Result 11, Processing Time 0.02 seconds

Fault Detection in the Two-for-One Twister

  • Park, Ho-Cheol;Koo, Doe-Gyoon;Lee, Jie-Tae;Cho, Hyun-Ju;Han, Young-A;Sohn, Sung-Ok;Ji, Byung-Chul
    • International Journal of Control, Automation, and Systems
    • /
    • v.4 no.6
    • /
    • pp.763-768
    • /
    • 2006
  • The two-for-one(TFO) twister is precision machinery that twists fibers rapidly under constant tension. Since the quality of the twisted yarn is directly deteriorated by faults of the twister, such as the distortion of the spinning axis, bearing abrasion, and tension irregularity, it is important to detect faults of the TFO twister at an early stage. In this research, a new algorithm is proposed to detect faults of the TFO twister and their causes, by measuring the vibrations of the TFO twister and obtaining frequency components with a FFT algorithm. The TFO twister with faults showed increased vibrations and each fault generated vibrations at different frequencies. By analyzing changes of characteristics of vibrations, we can determine faulty twisters. The proposed fault detection algorithm can be implemented cheaply with a signal processor chip. It can be used to find when to repair a faulty TFO twister without much loss of yam on-line.

A Literature Review on Trauma from Occlusion (교합성 외상에 관한 논쟁의 고찰)

  • Park, Go-Woon;Kim, Dae-Gon;Park, Chan-Jin;Cho, Lee-Ra
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.27 no.4
    • /
    • pp.423-436
    • /
    • 2011
  • Trauma from occlusion (TFO) is a pathologic alterations which develop in the periodontium as a result of undue masticatory force. The purpose of this article is to review the controversies about TFO. There are evidences that TFO is a risk factor in the progression of periodontitis. Tooth mobility should be reduced by selective occlusal adjustment. TFO can be developed dependent on the masticatory pattern, occlusion and anterior overbite in sound periodontal conditions. Secondary TFO may aggravate unstable occlusion. If "loss of posterior support" was occur, the problems were worsen. Extrusion, migration, rotation and pathologic deviation can be resulted. Opposite contention is the "shortened dental arch" concept. However, these two concepts persue the occlusal stability together. To treat TFO adequately, exact diagnosis and multi-disciplinary treatment should be needed.

Enzymatic Synthesis of Low-trans Fats Containing Conjugated Linoleic Acids and Their Physicochemical Characteristics (Conjugated Linoleic Acid(CLA)를 함유한 기능성 저트랜스 유지의 효소적 합성 및 이화학적 특성 연구)

  • Nam, Ha-Young;Lee, Ki-Teak
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.37 no.6
    • /
    • pp.752-760
    • /
    • 2008
  • Scale-up production of low-trans fat containing conjugated linoleic acid (CLA-TFO) was performed through lipase-catalyzed synthesis. Blend of fully hydrogenated soybean oil, olive oil containing conjugated linoleic acid and palm oil with 1:2:7 ratio was interesterified through Lipozyme RM IM in the 1 L-batch type reactor at $65^{\circ}C$ for 12 hrs, and the physicochemical and melting properties of CLA-TFO were compared with conventional (high trans fat) or commercial low-trans fat shortening. The trans fatty acids content in the conventional shortening (48.8 area%) was much higher than that of low-trans shortening (0.4 area%) and CLA-TFO (0.3 area%+CLA; 7.6 area%). Acid, saponification and iodine values of CLA-TFO were 0.4, 173.9 and 59.0, respectively. Their ${\alpha}$-, ${\gamma}$-tocopherol contents showed 4.7, 1.0 mg/100 g. Differences were observed in the solid fat contents (SFC), melting point of the conventional or low-trans fat and CLA-TFO. Each SFC of conventional, low-trans fat and CLA-TFO was 32.0, 29.3 and 30.4% with melting point of 38.5, 43.0 and $39.5^{\circ}C$ at $35^{\circ}C$, respectively. In texture profile analysis, hardness of conventional, low-trans fat and CLA-TFO was 111.7, 75.2 and 63.8 g.

Physical Properties and Low Temperature Resistance of Recycled Binder (재생 아스팔트 바인더의 물리적 특성과 저온균열 저항성 연구)

  • Lee, Young-Gwan;Kim, J.E.;Do, Young-Soo;Kim, Kwang-Woo
    • International Journal of Highway Engineering
    • /
    • v.6 no.4 s.22
    • /
    • pp.1-12
    • /
    • 2004
  • This study evaluated the asphalt binder characteristics for the hot-recycled asphalt mixture in which RAP was added in ambient temperature for surface course as well as for base course. RAPs were collected from four sources and their physical properties were evaluated. Mix designs were performed using 10 and 20% RAP contents for surface courses and 10, 20 and 30% for base courses. A virgin asphalt with the penetration grade of 60-80 was used for mixing recycled mixtures. Physical properties of recycled binders, including penetration, absolute viscosity, GPC, BBR and penetration after TFO were measured. From the results, regression analysis of absolute viscosity versus LMS in GPC showed $R^2$ being over 0.95, showing that GPC results estimate the absolute viscosity with relative accuracy. In BBR test, the resistance of recycled mixtures at low service temperature was inferior to the control, because the low temperature PG of recycled binder was one grade higher than that of the control binder.

  • PDF

PERIODONTAL DISEASE CAUSED BY TRAUMA FROM OCCLUSION IN A CHILD (외상성 교합으로 인한 어린이의 치주질환)

  • Choi, Byung-Jai;Ko, Dong-Hyun;Kim, Seong-Oh;Lee, Jae-Ho;Son, Heung-Kyu
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.31 no.3
    • /
    • pp.448-452
    • /
    • 2004
  • Trauma from occlusion(TFO) is injury to the periodontal tissue as a result of occlusal forces. Mobility is a common clinical sign of occlusal trauma. In acute occlusal trauma, this may be accomanied by pain, tenderness to percussion, thermal sensitivity, and pathologic tooth migration. Chronic occlusal trauma may be marked by excessive wear and gingival recession. Radiographic finding include a widened periodontal ligament space, radiolucence and condensation of the alveolar bone and root resorption. TFO is related to the pathogenesis of periodontal disease. It can cause increased tooth mobility TFO itself does not initate or aggravate marginal gingivitis or initiate periodontal pockets. Active trauma can accelerate bone loss, pocket formation and gingival recession depending on the presence of local irritants and inflammation. Gingival recession associated with occlusal forces includes traumatic crescent, McCall's festoon and Stillman's cleft. TFO plays a minor role in the pathogenesis of early to moderate periodontitis. A 5-year-old male visited Yonsei University Pedodontics clinic with a chief complaint about gingival recession. Mobility, excessive wear, gingival recession were detected by clinical exam on the both mandibular deciduous ca nine. On the radiographic view, vertical alveolar bone loss was observed on both mandibular deciduous canine.

  • PDF

Clinical Significance of Lateral Ankle Radiograph after the Reduction of a Syndesmosis Injury (원위경비인대결합 손상 정복 후 관찰된 측면 방사선 영상의 임상적 중요성)

  • Suh, Jae Wan;Park, Hyun-Woo
    • Journal of Korean Foot and Ankle Society
    • /
    • v.21 no.4
    • /
    • pp.128-134
    • /
    • 2017
  • Purpose: To introduce reliable and newly developed radiographic measures based on a lateral ankle radiograph to assess a syndesmotic reduction after screw fixation and to compare with the radiographic measures based on the anteroposterior (AP) and mortise radiographs. Materials and Methods: The postoperative ankle radiographs of 34 ankle fracture cases after screw fixation for concurrent syndesmosis injury were reviewed. Two radiographic parameters were measured on each AP and mortise radiograph; tibiofibular clear space (TFCS) and tibiofibular overlap (TFO). Five radiographic parameters were measured on the true lateral radiographs; the anteroposterior tibiofibular (APTF) ratio, anterior tibiofibular ratio (ATFR), posterior tibiofibular ratio (PTFR), distances of intersection of the anterior fibular border and the tibial plafond to anterior cortex of the tibia (AA'), and the intersection of posterior fibular border and tibial plafond to the tip of the posterior malleolus (BB'). In addition, the distance (XP) between the fibular posterior margin (X) crossing tibial plafond or the posterior malleolus and posterior articular margin (P) of the tibial plafond was measured on the lateral view. Results: Using TFCS and TFO in the AP and mortise radiographs, malreductions of syndesmosis were estimated in 17 of 34 cases (50.0%). Using the introduced and developed radiographic measures in the lateral radiographs, syndesmotic malreductions were estimated in 16 out of 34 cases (47.1%). Seventeen cases (50.0%) showed no evidence of postoperative diastasis using the radiographic criteria on the AP and mortise view, 10 cases (58.8%) of whom showed evidence of a malreduction on the lateral radiograph. The newly developed measurements, XP, were measured 0 in 11 out of 34 cases (32.4%). Conclusion: The reduction of syndemosis after screw fixation can be accurately assessed intraoperatively with a combination of several reliable radiographic measurements of the lateral radiograph and traditional radiographic measurements of the AP and mortise radiograph.

Design of AF Lens Actuator using IPMC-EMIM (IPMC-EMIM을 이용한 AF Lens Actuator 설계)

  • Kim, Sung-Joo;Kim, Chul-Jin;Yang, Hyun-Seok;Park, Young-Pil;Park, No-Cheol;Park, Gang-Ho;Lee, Hyung-Gun;Choi, Nak-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2007.11a
    • /
    • pp.829-833
    • /
    • 2007
  • IPMC-EMIM (Ionic Polyer Metal Composites + 1-ethyl-3- methyl imidazolium trifluromethane sulfonate, EMIM-Tfo) is fabricated by substituting ionic liquid for water in Nafion film, which improves water sensitiveness of IPMC and guarantees uniform performance regardless of the surrounding environment. In this paper, we will introduce the design and analysis of AF Lens Actuator using IPMC-EMIM. We will briefly introduce the procedure of fabrication of IPMC-EMIM first, and proceed on to define the necessary variables, analyze performance by changing the value of the variables, make a designed AF Lens Actuator, and measure the performance of one of them.

  • PDF

Relationship Between Dinoflagellate Cyst Distribution in Surface Sediments and Phytoplankton Assemblages from Gwangyang Bay, a Southern Coastal area of Korea (한국 남해 연안 광양만 표층 퇴적물의 와편모조류 시스트 분포 특성과 식물플랑크톤 군집과의 비교)

  • 김소영;문창호;조현진
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.8 no.2
    • /
    • pp.111-120
    • /
    • 2003
  • To describe dinoflagellate cysts from Gwangyang Bay, surface sediment samples were collected at 20 sites by the TFO core sampler on 24 August 2001, in coupled with a phytoplankton investigation by surface seawater sampling. More than 17 genera, 36 species of dinoflagellate cysts were Identified from the sediment samples of Gwangyang Bay, consisting of 14 species of gonyaulacoid, 14 species of protoperidinioid, 3 species of diplopsalid, 2 species of gymnodinioid, 1 species of tuberculodinioid and calciodinellid, respectively. Cyst concentrations in Gwangyang Bay varied from 115 to 2,188 cysts/g, and generally increased toward a western part of the study area. The highest cyst concentration was observed at St. 11 located in the northwestern region with 11 genera and 19 species(2,188 cysts/g), while the lowest value with 6 genera and 9 species(115 cysts/g) was observed at St. 3 located in the center of the study area. The predominant dinoflagellate cyst was Spiniferites bulloideus, followed by Alexandrium sp., Brigantedinium simplex and S. delicatus. The motile forms of eight dinoflagellate cysts recorded in the sediment samples were also observed in the seawater: Polykrikos swartzii/kofoidii complex, Scripssiella trochoidea, Protoperidinium claudicans(cyst name: Votadinium spinosum), P. pentagonum(: Trinovantedinium capitatum capitatum), P. conicum(: Selenopemphix quanta), P. leonis(: Quinquecuspis concretum), P. conicoides(: Brigantedinium simplex), Gonyaulax spp.(: Spiniferites spp.). In this study, heterotrophic dinoflagellate cysts show the highest concentration at St. 6 where the highest density of diatoms simultaneously observed from surface water sample. This result suggests that the grazing of heterotrophic dinoflagellates on the diatoms in high concentration caused the higher concentration of heterotrophic dinoflagellate cysts.

A Case Report and Review on Cross-Arch Fixed Partial Denture with Severely Reduced Periodontal Tissue Support (심하게 감소된 치주지지를 갖는 Cross-Arch Fixed Partial Denture에 대한 고찰 및 증례보고)

  • Oh, Sang-Chun;Kim, Yun-Sang;Kim, Yu-Jin;Kim, Min-Jeong
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.28 no.3
    • /
    • pp.309-318
    • /
    • 2012
  • In advanced stages of periodontal disease, a lot of the periodontal tissue support are usually lost. The tissue destruction around some teeth is progressed to a level which requires either spontaneous exfoliation or extraction of several teeth due to their excessive mobility. In such cases, a comprehensive treatment plan encompassing the adequate periodontal and maintenance therapy, as well as perio-prosthetic treatment involving occlusal equilibration, is needed in order to restore health, function, and esthetics. Cross-arch fixed partial dentures(CAFPDs), one of the perio-prosthetic treatments, are used to stabilize the teeth with severely reduced periodontal tissue support. Unfortunately, however, a little is known about the occlusal scheme and biomechanical concept of CAFPDs. This paper will demonstrate summaries of the trauma from occlusion(TFO), Ante's law revisited, the treatment principles, the role of occlusion, and the long-term consequences for CAFPDs, and the possibility of CAFPDs through a case presentation.

A comparative study of bite force associated with remaining bone level in anterior and premolar teeth at periodontal maintenance phase (유지관리기 치주환자의 전치 및 소구치에서 잔존 치조골량에 따른 교합력의 비교 연구)

  • Song, Gyu-Won;Yim, Sung-Bin;Chung, Chin-Hyung
    • Journal of Periodontal and Implant Science
    • /
    • v.32 no.3
    • /
    • pp.643-653
    • /
    • 2002
  • Periodontal supporting tissue goes through destruction by chronic inflammatory periodontal disease as two aspect. One is qualitive aspect such as alteration of periodontium, the other is quantitative aspect such as alveolar bone loss. According to many authors, PDL is responsible for biting force, and there are two mean. for measuring PDL's function - mobility test and biting force test. This study was conducted to compare the biting force with remaining bone level, that is, quantitative aspect of periodontium, in anterior and premolar teeth at periodontal maintenance phase. 17 patients on periodontal maintenance phase during 6 months at minimum were selected for this study. For the same condition, 4 anterior, canine, premolar teeth were tested by MPM-3000 bite-force register at the same time(a.m.l0-12), the same position, the same posture, by the same examiner. Patients of TMI), ill-fitting pros thesis, general disease, malocclusion and the teeth of TFO, absence of opposing teeth, malposition were excluded. Remaining bone level was measured on the panorama X-ray film through 5 level from 1mm below CEJ to root apex. Teeth were examined twice, and bigger one was selected. If the values showed large difference. examinatin was re-done and the mean was selected. The results were as follows ; 1. In the 4 anterior group, as the remaining bone is decreased, the average of maximal biting force is decreased. Especially, at 3/5 bone level, maximal biting force is decreased significantly(p<0.01). 2. In the canine group, as the remaining bone is decreased, the average of maximal biting force is decreased. Especially, at 2/5 bone level, maximal biting force is decreased significantly(p<0.01). 3. In the premolar group, as the remaining bone is decreased, the average of maximal biting force is decreased. Especially, at 3/5 bone level, maximal biting force is decreased significantly(p<0.05). From the results of this study, clinicians could utilize these efficiently when they have to determine the proper restorative materials, time for tooth extraction, treatment plan, prognosis.