• 제목/요약/키워드: Frontal

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Frontal Plane Motion with Pelvis and Waist Joint Rotations in Bipedal Walking

  • Ha, Tae-Sin;Kim, Joo-Hyung;Choi, Chong-Ho
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.2248-2253
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    • 2005
  • Although the progress in bipedal walking is impressive in recent years, biped robots still require very high torque and can walk only for a short time interval with their internal batteries. Therefore, further research needs to be carried out to enhance walking efficiency of these robots. In order to achieve this goal, we attempt to imitate human walking with pelvis and waist joint rotations in the frontal plane. In order to investigate the effect of the pelvis and waist joint rotations in the frontal plane motion, we study the frontal plane model with a triangular structure made up of a waist joint and two hip joints. Through simulation, we show that the pelvis rotation can reduce the maximum torque and the control effort, and the waist joint rotation can reduce the trunk sway caused by the pelvis rotation. The combination of these two rotations makes the bipedal walking in the frontal plane more efficient.

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Morphology of the Aging Forehead: A Three-Dimensional Computed Tomographic Study

  • Yi, Hyung Suk
    • 대한두개안면성형외과학회지
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    • 제16권2호
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    • pp.58-62
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    • 2015
  • Background: Age-related changes have been studied for lower and middle facial bones. Although the forehead comprises one-third of the facial area, no studies have investigated age-related changes in the upper part of the face or forehead. The purpose of this study was to use three-dimensional computed tomography (3D CT) to investigate age-related changes in the frontal bone. Methods: A retrospective review was performed for patients who underwent 3D CT scan of facial bones. Patients were divided by gender and age (20 to 40 years, 41 to 60 years, and above 60 years). The frontal bone curvature was evaluated by the length of frontal bone and by two frontal bone angles in relation to the Frankfurt horizon. Results: In both genders, aging was associated with increasing lower slope length. In elderly men (>60 years), the upper slope angle was significantly higher when compared to younger male subjects. Women demonstrated similar age-related changes, but the differences were only statistically significant for the middle and older age groups. Conclusion: This study demonstrates quantifiable age-related changes in the frontal bone. These findings contribute to the understanding of age-related changes of the facial soft tissues. The mean measurements in each age group can be used as a reference when planning forehead reconstruction.

신 정면 충돌 시험의 시뮬레이션 비교 분석 (Simulation Analysis and Comparison of New Frontal Impact Tests)

  • 정경진;윤영한;박지양;김동섭;오명진;곽영찬;손창기;신재곤;이은덕;권해붕
    • 자동차안전학회지
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    • 제9권2호
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    • pp.20-25
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    • 2017
  • KNCAP is a program to evaluate the automobile safety, providing consumer vehicle safety assessment results. The safety evaluation tests are Frontal Impact, Offset Frontal Crash, Side Crash, Side Pole Crash, Rear Impact. This is the study of the offset frontal impact safety evaluation. Currently, IIHS is performing a small overlap test. NHTSA plans to implement the oblique moving deformable barrier test. Euro-NCAP plans to implement a mobile frontal impact test. Simulation is used to compare occupant behavior and injury. We have investigated whether the introduction of the test at KNCAP is necessary. The dummy model used in the simulation was the 50th percentile male Hybrid III dummy.

Comparison of the Surgical Approaches for Frontal Traumatic Intracerebral Hemorrhage

  • Park, Eun Sung;Moon, Seong Keun;Eom, Ki Seong
    • Journal of Trauma and Injury
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    • 제32권2호
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    • pp.71-79
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    • 2019
  • Purpose: Recent developments in minimally invasive techniques have the potential to reduce surgical morbidity, promote patient recovery, accelerate surgical procedures, and thus improve cost-effectiveness in case management. In this study, we compared the treatment efficacy and results of supraorbital keyhole approach (SOKA) with those of conventional unilateral frontal craniotomy (CUFC) for traumatic intracerebral hemorrhage (TICH) in the frontal lobe. Methods: We analyzed the data of 38 patients who underwent CUFC (n=30) and SOKA (n=8) and retrospectively reviewed their medical records and radiological findings. Furthermore, we tried to identify the best surgical method for such lesions by including patients who underwent burr hole aspiration and drainage (BHAD) (n=9) under local anesthesia due to various circumstances. Results: The difference in the initial Glasgow coma scale score, operative time, and length of hospitalization between the CUFC and SOKA were statistically significant. All radiological features between the two groups including associated skull fracture, amount of pre- and postoperative hematoma, percentage of complete hematoma removal, pre- and postoperative midline shifting of the hematoma, and development of postoperative delayed hematoma were not statistically significant. Our experience of 46 patients with TICH in the frontal lobe with any of the three different surgical methods including BHAD enabled us to obtain valuable findings. Conclusions: Although it is difficult to insist that one particular approach is more useful than the other, we are confident that SOKA will have more advantages over CUFC in carefully selected patients with frontal TICH depending on the surgical experience of a neurosurgeon.

전두동의 크기와 하악골 성장예측에 관한 연구 (A STUDY ON THE MANDIBULAR GROWTH PREDICTION AND SIZE OF THE FRONTAL SINUS)

  • 경승현;유영규
    • 대한치과교정학회지
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    • 제27권3호
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    • pp.473-479
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    • 1997
  • 성장기 환자의 치료 계획 수립시 치아 이동만으로 치료를 할 것인지, 악 정형 치료를 동반할 것인지, 아니면 성장후 수술을 할 것인지를 결정하는 일은 쉬운 일이 아니며 특히, 악골의 성장을 예측하는 과정을 치료계획 수립에 매우 중요한 부분이다. 전두동은 조기에 성장이 완료되고 하악골은 20세까지 성장을 지속한다는 점에 착안하여, 측모 두부방사선 사진상에 나타나는 전두동의 크기와 하악골 크기간에 상관성을 알아보기 위해 228명을 골격선 제I급, 제II급, 제III급 부정교합의 3군으로 분류하고 하악골의 장경과 악골의 전후방 관계를 나타내는 3가지 지수(ANB, APDI, Wits)를 측정하여, 서로간의 상관성을 검토한 결과 다음의 결론을 얻었다. 1. 전두동의 크기와 ANB(-0.3633), APDI(0.296), Wits(-0.2380), 하악골 장경(0.2704)은 높은 상관성을 (p<0.001) 보였다. 2. 골격성 제III급 부정교합군에서, 측모두부 방사선 사진상에 나타나는 전두동의 크기가 골격성 제 I 급 부정교합군이나 II 급 부정교합군보다 크게 나타났다.

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소절개 및 Dual-top screw를 이용한 전두동 전벽 단순 함몰골절의 치료 (Small Incision and Dual-Top Screws for Treatment of Simple Depressed Anterior Frontal Sinus Fractures)

  • 문석호;오득영;서병철;이종원;안상태
    • Archives of Plastic Surgery
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    • 제35권3호
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    • pp.345-348
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    • 2008
  • Purpose: Fracture of the frontal sinus accounts for 5-15% of all facial fractures. Only anterior table fracture occupies one third of the frontal sinus fracture. Conventional coronal approach is the standard treatment, but this method is very aggressive, especially in patient with simple, depressed, anterior frontal sinus wall fracture. We introduce new, simple technique for these patients, using small incision and Dual-top screws. Methods: A 27-year-old male patient was introduced to our department under the impression of fracture of frontal sinus, involving only anterior table. Under general anesthesia, 1.5 cm-sized, small incision was made on the suprabrow area. We reduced fractured fragment with two dual-top screws and 25G wires. Fixation was not necessary Results: The operation took about forty minutes, and the patient discharged 2 days after the operation. Postoperative 2 months follow up CT shows maintenance of reduction site. Gross depression of the forehead and visible scar was not observed. Conclusion: Although the indication of this procedure is limited, less aggressive, simple and very effective to the patient with simple. depressed, anterior frontal sinus fracture.

두개골 골이식을 이용한 전두골 골종의 치험례 (A Case Report in Treatment of the Frontal Sinus Osteoma using Cranial Bone Graft)

  • 신진용;노시균;이내호;양경무
    • Archives of Plastic Surgery
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    • 제37권3호
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    • pp.309-312
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    • 2010
  • Purpose: An osteoma is one of the common benign tumors that penetrate the nasal portion, paranasal and frontal sinus. This tumor is mostly found by radiation test accidentally, however in rare cases; it can be found to be touched or with its symptoms as the tumor grows. We report this case since we found and healed the benign tumor which was affecting orbit and the both sides of fronal sinus. Methods: A 19 year old female patient visited to our hospital due to the mass on her forehead. The symptoms began 3 years ago but no special symptom was found except for touchable mass. She was diagnosed as the osteoma of superior orbital parts and both sides of frontal sinus using X-ray and CT scanning. The size of osteoma was $5{\times}2.5{\times}3.5\;cm$ and indicated the patterns penetrated to the right side of orbital region. The osteoma excision was conducted with coronal incision and wide area of defect part in frontal sinus and superior orbital part were reconstructed by cranial bone graft and resorbable fixation plates. Results: The patient recovered without any postoperative infections or complications and symptoms. Dysaesthesia was found on her frontal area but improved in 1 month after the surgery. Conclusion: The occurrences of osteoma in frontal sinus are rare and can be treated with conservative methods if there are no infections and symptoms. We report this case since we found the benign tumor, which was affecting orbit and the both sides of fronal sinus and healed it with coronal resectomy without any complications.

좌측 전두엽 손상자의 화행이해능력 특성 및 화행이해능력과 실행기능의 상관 (Study on the speech act comprehension characteristics and the correlation between the speech act comprehension characteristics and executive function in Individuals with a Left Frontal Brain Injury)

  • 김지채;이은경
    • 한국산학기술학회논문지
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    • 제15권9호
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    • pp.5495-5501
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    • 2014
  • 본 연구는 좌측 전두엽 손상자(Individual with Left Frontal Lobe Injury, ILFLI)의 화행이해능력을 평가하고 화행이해능력과 실행기능 간의 상관을 살펴보았다. 연구대상은 ILFLI집단 18명과 정상 성인집단 18명으로 하였으며, 이들에게 화행이해능력검사와 Kims 전두엽-실행기능 검사 중 EXIT를 실시하여 화행이해능력과 EIQ를 측정하였다. 연구결과 ILFLI가 정상성인 보다 화행이해능력과 실행기능이 낮게 나타났으며, ILFLI의 화행이해능력과 실행기능 간에는 유의미한 상관이 있는 것으로 나타났다. 따라서 ILFLI는 화행이해능력에 손상이 있으며, 이를 향상시키기 위해서는 전통적인 언어치료 접근법과 더불어 실행기능을 향상시키기 위한 프로그램이 함께 이루어져야 함을 제언하는 바이다.

전달매트릭스법에 있어서 해의 수험특성에 관한 연구 (A Study on the Convergence Characteristics for the Solution of Transfer Matrix Method)

  • 김영식
    • 수산해양기술연구
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    • 제26권3호
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    • pp.282-287
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    • 1990
  • 종래의 전달매트릭스법과 Frontal 전달매트릭스법에 있어서의 계산의 안정성과 효율성을 검토하고 또 이 두 방법에 선형내삽법을 적용하여 각 방법에 의한 해의 수렴특성을 분석한 결과를 요약하면 다음과 같다. 1. 시행값이 작을 경우 두 방법에 의한 계산의 안정성이나 정확성의 면에서 전혀 차이가 없으나, 시행값이 커질수록 전달매트릭스법에 의한 계산의 오차가 증대해지고, 어느 시행값이 이상이 되면 계산이 불안정해 진다. 2. Frontal 전달 매트릭스법은 시행값의 선택에 큰 제약을 받으며, 적절한 시행값을 선택하지 못 했을 경우, 원하는 해를 구할 수 없다. 3. Frontal 전달 매트릭스법에 의한 시행값-진동수행렬식의 값이 plot에 있어서는 불연속점이 존재하고, 이 불연속점을 경계로 plot는 + 혹은 -의 최대값으로 발산하며 다시 새로운 연속구간이 시작된다. 양단의 경계조건이 같을 경우에는 +에서 -로 바뀌는 연속구간내에, 양단의 경계조건이 다를 경우에는 -에서 +로 바뀌는 연속구간내에 해가 존재한다. 4. 선형내삽법을 적용할 때 근사해로의 수렴에 필요한 반복회수는 Frontal 전달 매트릭스법이 훨씬 많으며 한 시행값에 대한 계산시간도 더 많이 필요하므로 근사해를 구하는 전체적인 계산시간은 연속매트릭스법에 비해 훨씬 더 많이 소요된다. 5. Frontal 연속매트릭스법에 의한 계산은 경계조건이나 중간조건에 따라 매트릭스 요소를 기지와 미지로 재배치해야 하고 또는 시행값의 선택이나 불연속구간의 판별 등 많은 제약이 따르므로 프로그램의 작성과 그 실행이 연속매트릭스법에 비해 훨씬 번거롭다.

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대복, Gomphina veneriformis 아가미의 조직학적 변화와 산소소비율에 미치는 TBTCl의 독성 (Tributyltin chloride (TBTCl) toxicity on the oxygen consumption rate and histological changes of gill in the equilateral venus, Gomphina veneriformis (Bivalvia: Veneridae))

  • 박정준;이정식
    • 한국어병학회지
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    • 제21권1호
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    • pp.67-79
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    • 2008
  • This study was conducted to find out biological response of bivalves exposed to tributyltin chloride(TBTCl). The results of the study confirmed that TBTCl induce the reduction of oxygen consumption rateand histopathological feature in the gill structure of equilateral venus, Gomphina veneriformis. The experi-mental groups consisted of a control and 3 TBTCl exposure groups (0.4, 0.6 and 0.8 yg TBTCl L') and theexperimental period was 36 weeks. For histological analysis, gill tissues were fixed in Bouin's fluid andthen stained H-E stain, AB-PAS (PH 2.5) reaction and Masson's trichrome stain after having serially sec-tioned the tissue by paraffin method at thickness of 4-6 (an. The oxygen consumption rate was not signifi-cantly different between the control and exposure groups at 4 weeks, but in all exposure groups at 28 weeks,it was significantly different to the control. Gill of G. veneriformis had demibranch that attached two sheetsof lamellae and a lamella was composed of numerous filaments, numbering 25 on average. The frontal fila-ment zone had three types of cilia; frontal, latero-frontal and lateral depending on locations while the lateralcilia were the longest and largest in number. The mucous cells observed in filaments were more abundant in(542c) in AB-PAS (PH 2.5) reaction. Gill exposed to TBTCl was extended hemolymph sinus and increased hemocytes at 4 weeks, and then it showed increases of mucous cells and partially disappearance of frontalcilia. In the group of 0.8 yg TBTCl L' at 12 weeks, hypertrophy of frontal and latero-frontal epithelia wasobserved. Also it observed m decrease of mucous cell containing weekly acid mucosubstance and appearedpartially destruction muscle fiber bundle, In the groups of 0.4 and 0.6 ug TBTCl L' at 36 weeks, it appearedpartially modification of epithelia and in 0.8 us TBTCl L' group, observed filaments that come out chiti-nous rod from disappearance of frontal and latero-frontal epithelia.