• 대한토목학회논문집
• /
• 제41권6호
• /
• pp.663-673
• /
• 2021

해안구조물 설계시 허용평균월파량은 설계요소중의 하나이며, 구조물의 마루높이는 구조물의 안전, 보행자의 안전 및 운영 등에 요구되는 월파량 이하가 되도록 하여야 한다. 최근 들어 보다 안전한 설계를 위해 평균월파량보다 개별 최대월파량을 기준으로 적용하자는 제안이 이루어지고 있다. 본 연구는 비쇄파조건에서 개별 최대월파량에 대한 정보를 제공하고자 하는 것이며, 경사식구조물의 기하학적 형상을 고려안 2차원 수리모형실험을 수행하였다. 또한 실험을 위해 새로운 계측방법을 고안하였다. 실험결과를 이용하여 평균월파량에 기반하여 개별 최대월파량을 산정할 수 있는 경험식을 제안하였다. 그리고 피복재 어깨폭에 따른 평균월파량의 저감효과에 대해서도 검토하였다.

• Journal of Periodontal and Implant Science
• /
• 제52권1호
• /
• pp.3-27
• /
• 2022

Purpose: This study was conducted to evaluate and compare the effects of different graft materials used in alveolar ridge preservation on dimensional hard tissue changes of the alveolar ridge, assessed using cone-beam computed tomography (CBCT) scans. Methods: A systematic electronic search of MEDLINE and the Cochrane Central Register of Controlled Trials and a manual search were conducted from November 2019 until January 2020. Randomized controlled trials were included if they assessed at least 1 variable related to vertical or horizontal hard tissue changes measured using CBCT scans. After a qualitative analysis of the included studies, subgroups were formed according to the graft material used, and a quantitative analysis was performed for 5 outcome variables: changes in vertical alveolar bone height at 2 points (midbuccal and midpalatal/midlingual) and changes in horizontal (buccolingual) alveolar bone width at 3 different levels from the initial crest height (1, 3, and 5 mm). Results: The search resulted in 1,582 studies, and after an independent 3-stage screening, 16 studies were selected for qualitative analysis and 9 for quantitative analysis. The metaanalysis showed a significantly (P<0.05) lower reduction of alveolar ridge dimensions for the xenogenic subgroup than in the allogenic subgroup, both vertically at the midbuccal aspect (weighted mean difference [WMD]=-0.20; standard error [SE]=0.26 vs. WMD=-0.90; SE=0.22) as well as horizontally at 1 mm (WMD=-1.32; SE=0.07 vs. WMD=-2.99; SE=0.96) and 3 mm (WMD=-0.78; SE=0.11 vs. WMD=-1.63; SE=0.40) from the initial crest height. No statistical analysis could be performed for the autogenic subgroup because it was not reported in sufficient numbers. Conclusions: Less vertical and horizontal bone reduction was observed when xenogenic graft materials were used than when allogenic graft materials were used; however, the loss of alveolar ridge dimensions could not be completely prevented by any graft material.

• 콘크리트학회논문집
• /
• 제25권1호
• /
• pp.53-61
• /
• 2013

코일철근의 직선화 가공성을 향상시키기 위한 마디 형상으로, 철근 축과 마디 사이각 $50^{\circ}$, 마디 윗면 폭(crest width) $0.15d_b$, 마디의 종단면 각도(flank inclination) $55^{\circ}$에 초승달 모양 지압면을 가진 생선뼈 마디(fishbone-shaped transverse rib)를 제안하였다. 이 형상은 직선화 기계의 롤러 홈(groove)과 철근 외부의 접촉면적을 넓혀 마디 손상을 최소화하며 직선도를 향상시키고 가공 생산성을 높일 것으로 기대된다. 제안된 형상을 포함하여 마디 각도가 상이한 3종류의 코일철근(SD500D16 강종)에 대한 부착강도 평가를 위해 겹침이음실험을 실시하였다. 3종의 코일철근은 기존 부착강도 평가식에 따른 예측값보다 평균 10%이상 높은 부착강도를 지닌 것으로 평가되었다. 이것은 코일철근의 상대마디면적비가 기존 평가식 유도에 사용된 실험보다 높기 때문으로 판단된다. 부착강도에 대한 직선철근과 코일철근의 상관계수(correlation coefficient)는 0.94이상 이였으며, 코일철근의 부착성능이 직선철근과 거의 유사함을 알 수 있다. 따라서 실험에 사용된 코일철근의 정착길이와 이음길이 설계에 현행설계기준을 적용하는 것이 타당한 것으로 평가된다.

• 한국지반공학회지:지반
• /
• 제13권4호
• /
• pp.37-54
• /
• 1997

본 논문은 비점착성 사질토 성토 사면에 인접한 대상기초의 극한지지력 및 파괴메카니즘에 관 한 연구로서 지반의 상대밀도, 기초 폭, 사면 경사각, 사면 정부로 부터 기초까지의 거리가 기초 의 하중침하특성과 극한지지력, 경사지반의 파괴메카니즘에 미치는 영향을 조사하기 위하여 비 점착성 사질토 모형사면에서 2차원 평면변형 실험을 수행하였다. 모형실험에서는 주문진 표준사를 사용하여 상대밀도가 45%와 70%로 조성된 1:1.5및 1:2의 모형사면을 성형하고 폭이 4, 7, 10, 12cm의 대상 강성 모형기초를 사용하였다. 또한 기초의 재하위치는 사면 정부로 부터 기초까지의 거리를 기초 폭으로 나눈 값 즉, 0, 0.5, 1, 2, 3, 4, 5로 변화시키면서 실험을 수행하였다. 이와같이 사면 정부로 기초의 재하위치를 점진적으로 변화시키므로써 관찰된 활동선 형성의 파괴메카니즘을 기존의 해석 방법들과 비교 분석하였으며, 실험을 수행하여 측정한 극한지지력을 한계평형법과 극한해석법 그리고 실험결과에 의한 경험식과 비교하여 지반의 상대밀도, 기초의 폭 및 기초 재하위치의 변화가 극한지지력 및 하중친하 특성, 파괴메카니즘에 미치는 영향을 조사하였다.

• 대한치과보철학회지
• /
• 제47권2호
• /
• pp.240-246
• /
• 2009

연구목적: 이 연구는 측방접근법을 통해 상악동 골이식을 시행한 후 임플란트를 식립하였을 때, 누적 생존률 및 성별, 연령별, 이식재, 자가골의 공여부, 술전 잔존골 양, 무치악 형태, 식립 시기, 임플란트 종류, 직경과 길이에 따른 임플란트의 생존률 및 변연골의 방사선학적 결과의 차이를 분석하고자 시행되었다. 연구 재료 및 방법: 상악 구치에 측방접근법을 통해 상악동 골이식술 후 임플란트 보철치료를 시행한 71명을 대상으로 하였으며 표면 처리된 나사모양의 임플란트를 사용하였다. Osseotite(BIOMET 3i, Warsaw, USA), Neoplant(Neobiotec, Seoul, Korea), $Br\ddot{a}nemark$(Nobel Biocare, Goteberg, Sweden)과 SSII(Osstem, Busan, Korea)를 사용하였다. 최소 6개월 이상의 기간 관찰 누적 생존률은 Kaplan-Meier 분석법을 이용하였으며 다른 요소에 따른 임플란트의 생존률의 유의성은 Chi-square test로 검정하였다. 결과: 상악동골 이식술이 시행된 모든 증례에서 임플란트 식립이 가능한 골 양이 얻어졌으며 92%의 생존률을 보였다. 결론: 상악동 골이식술을 시행한 후 임플란트 보철 수복은 자가골 단독 사용시에 자가골과 골대체 물질이 혼합된 것보다 우수한 생존률을 보였다. 지연 식립하는 경우가 임플란트와 동시에 식립하는 경우보다 생존률이 높았다.

• 대한의료기공학회지
• /
• 제20권1호
• /
• pp.118-147
• /
• 2020

Objective : The purpose of this study is to understand trends of pelvic correction therapy in Korea and to assist research activities on pelvic correction therapy. Also, this study selected and presented indicators for measuring pelvic slope to help ensure consistent studies with uniform indicators in future studies related to pelvic correction. Methods : The following keywords "골반", "골반 교정", "골반 변위" "Pelvic correction" were searched on three specialized search sites (RISS, NAI, DBpia). Trends in pelvic correction therapy were analyzed through the selected researches suitable among these searched researches in an overview format. Results : 1. A total of 7,806 studies were searched and a total of 268 studies were finally selected. 2. Studies began in 1977 and have been actively studied until recently, with 35 studies in 2017 being the most recent trend since 2000. 3. In the results according to the Main Field of Research, the 'Arts and Kinesiology'(113, 42.16%) and 'Medicine and Pharmacy'(103, 38.43%) were the most in order. To the Middle Field, the 'Kinesiology was the largest with 96(35.82%) studies. 4. In the results according to the study design, 'Pre-Post Test(PPT)' was the largest with 107 studies. 5. In the results according to the Intervention, 'Exercise' was the largest with 165 studies, of which 'Pilates' and 'Yoga' in 'Training' was the largest. 6. Among the evaluation method, the 'Pelvic Index' was used 146 times, followed by 'Spinal Alignment (99)', 'Other Joints (93)', and 'Kinetic Specialized Measurement Test (56)'. 7. Among the evaluation methods, the pelvic slope measurement indicators were PT (58), PH (48), Pelvic Torsion (40), Iliac Crest (38), ASIS-PSIS distance/angle (27), and Pelvic Width (I.W., I.L., S.W) (25) in order. 8. The journals that published the most researches were KJSS(Korean Alliance For Health, Physical Education, Recreation, And Dance;9), and JKPT(Korean Physical Therapy;9). Among the University, the Graduate School of Silla University published the most papers (12). 9. The author who published the most studies were Seungjin Park(3), the co-authors were Hoseong Lee, Gideok Park, Seongsu Bae(3), and the Thesis-Director Gyeongok Lee(7). Conclusions : 1. Studies on pelvic correction treatment continue to increase every year. 2. The main academic field of pelvic correction is 'Sports', 'Physical Therapy', and 'Medical Science'. 3. The most chosen research design method in the study on pelvic correction treatment was 'Pre-Post Test(PPT)', primarily as an intermediary, Pilates and yoga during exercise therapy, and then Chiropractic during handcraft were used as multiple frequencies. 4. Among the various measurement method indicators of pelvic correction previously used, multiple frequency was taken up in the order of PT, PH, Pelvic Torsion, iliac crest, ASIS-PSIS distance/angle, and pelvic width (I.W.,I.L.,S.W). Typically, measurements through "ASIS-PSIS angle" are recommended and are considered as the most rational in clinical trials.

• 한국해안·해양공학회논문집
• /
• 제26권2호
• /
• pp.103-111
• /
• 2014

크기가 작은 다수의 부이들이 원형으로 배열되어 있을 때 부이를 통한 추출 파워를 포텐셜이론 통하여 살펴보았다. 부이의 크기와 배열 간격이 수심과 파장 그리고 설치면적의 반경에 비하여 작다는 가정 아래에서 다수부이로 채워진 수면에서의 경계조건식을 유도하고 이를 포함한 경계치문제를 고유함수전개법을 이용하여 해석하였다. 추출 파워와 입사파 에너지의 비인 취득 폭을 packing ratio, 배열 반경, 그리고 PTO 감쇠계수를 바꿔가면서 살펴보았다. 또한 다수의 소형 부이를 원형 배열하였을 때 추출된 파력이 같은 잠긴 체적을 갖는 대형 단일 부이보다 효율적임을 계산을 통하여 밝혔다.

• Imaging Science in Dentistry
• /
• 제31권2호
• /
• pp.101-107
• /
• 2001

Purpose: To evaluate the precision of measurements of distances and angle in the cross-sectional views of linear tomogram of panorama and to assess the technique for visualizing the mandibular canal. Methods: Ten dry mandibles were radiographically examined with 3 continuous cross-sectional views of linear tomogram of panorama and 4 continuous computed tomograms. The distance between the superior border of canal and alveolar crest and the bucco-lingual width of alveolar bone at the level of the superior border of canal and the angle between the two lines above were measured. Measurements were performed by radiologist and implantologist group and compared with measurements on computed radiograms of the same areas. Results: The measurements differences for the distance of alveolar bone height between in panorama and in CT showed 0.9 mm±0.6 mm by radiologists and 1.3mm±0.8mm by implantologists. There was no statistically significant difference between two groups' measurements. The differences in measurements for the distance of alveolar bone width between in panorama and in CT showed 0.5mm±0.8mm by radiologists and 2.5mm±1.4 mm by implantologists. There was significant difference (P<0.05) between two groups' measurements. The average bucco-lingual inclination of alveolar bone above mandibular canal was average 95.8° in CT. The difference of measurements between two groups was average 1±0.9°. Three cross-sectional views of panorama could show that the mandibular canal crosses antero-lingually and slopes inferiorly from the posterior segment of the mandible. Conclusions: The measurements in the linear tomogram of panorama by radiologists gave the accurate values of the distances and the angle compared with the values in computed tomograms.

• 한국농공학회지
• /
• 제20권1호
• /
• pp.4592-4598
• /
• 1978

The purpose of this research is to find out mathemetically an economical intake water depth in the design of head works through the derivation of some formulas. For the performance of the purpose the following formulas were found out for the design intake water depth in each flow type of intake sluice, such as overflow type and orifice type. (1) The conditional equations of !he economical intake water depth in .case that weir body is placed on permeable soil layer ; (a) in the overflow type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }+ { 1} over {2 } { Cp}_{3 }L(0.67 SQRT { q} -0.61) { ( { d}_{0 }+ { h}_{1 }+ { h}_{0 } )}^{- { 1} over {2 } }- { { { 3Q}_{1 } { p}_{5 } { h}_{1 } }^{- { 5} over {2 } } } over { { 2m}_{1 }(1-s) SQRT { 2gs} }+[ LEFT { b+ { 4C TIMES { 0.61}^{2 } } over {3(r-1) }+z( { d}_{0 }+ { h}_{0 } ) RIGHT } { p}_{1 }L+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 }L+ { dcp}_{3 }L+ { nkp}_{5 }+( { 2z}_{0 }+m )(1-s) { L}_{d } { p}_{7 } ] =0}}}} (b) in the orifice type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }+ { 1} over {2 } C { p}_{3 }L(0.67 SQRT { q} -0.61)}}}} {{{{ { ({d }_{0 }+ { h}_{1 }+ { h}_{0 } )}^{ - { 1} over {2 } }- { { 3Q}_{1 } { p}_{ 6} { { h}_{1 } }^{- { 5} over {2 } } } over { { 2m}_{ 2}m' SQRT { 2gs} }+[ LEFT { b+ { 4C TIMES { 0.61}^{2 } } over {3(r-1) }+z( { d}_{0 }+ { h}_{0 } ) RIGHT } { p}_{1 }L }}}} {{{{+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 } L+dC { p}_{4 }L+(2 { z}_{0 }+m )(1-s) { L}_{d } { p}_{7 }]=0 }}}} where, z=outer slope of weir body (value of cotangent), h1=intake water depth (m), L=total length of weir (m), C=Bligh's creep ratio, q=flood discharge overflowing weir crest per unit length of weir (m3/sec/m), d0=average height to intake sill elevation in weir (m), h0=freeboard of weir (m), Q1=design irrigation requirements (m3/sec), m1=coefficient of head loss (0.9∼0.95) s=(h1-h2)/h1, h2=flow water depth outside intake sluice gate (m), b=width of weir crest (m), r=specific weight of weir materials, d=depth of cutting along seepage length under the weir (m), n=number of side contraction, k=coefficient of side contraction loss (0.02∼0.04), m2=coefficient of discharge (0.7∼0.9) m'=h0/h1, h0=open height of gate (m), p1 and p4=unit price of weir body and of excavation of weir site, respectively (won/㎥), p2 and p3=unit price of construction form and of revetment for protection of downstream riverbed, respectively (won/㎡), p5 and p6=average cost per unit width of intake sluice including cost of intake canal having the same one as width of the sluice in case of overflow type and orifice type respectively (won/m), zo : inner slope of section area in intake canal from its beginning point to its changing point to ordinary flow section, m: coefficient concerning the mean width of intak canal site,a : freeboard of intake canal. (2) The conditional equations of the economical intake water depth in case that weir body is built on the foundation of rock bed ; (a) in the overflow type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }- { { { 3Q}_{1 } { p}_{5 } { h}_{1 } }^{- {5 } over {2 } } } over { { 2m}_{1 }(1-s) SQRT { 2gs} }+[ LEFT { b+z( { d}_{0 }+ { h}_{0 } )RIGHT } { p}_{1 }L+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 }L+ { nkp}_{5 }}}}} {{{{+( { 2z}_{0 }+m )(1-s) { L}_{d } { p}_{7 } ]=0 }}}} (b) in the orifice type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }- { { { 3Q}_{1 } { p}_{6 } { h}_{1 } }^{- {5 } over {2 } } } over { { 2m}_{2 }m' SQRT { 2gs} }+[ LEFT { b+z( { d}_{0 }+ { h}_{0 } )RIGHT } { p}_{1 }L+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 }L}}}} {{{{+( { 2z}_{0 }+m )(1-s) { L}_{d } { p}_{7 } ]=0}}}} The construction cost of weir cut-off and revetment on outside slope of leeve, and the damages suffered from inundation in upstream area were not included in the process of deriving the above conditional equations, but it is true that magnitude of intake water depth influences somewhat on the cost and damages. Therefore, in applying the above equations the fact that should not be over looked is that the design value of intake water depth to be adopted should not be more largely determined than the value of h1 satisfying the above formulas.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제33권6호
• /
• pp.525-528
• /
• 2011

A deep circumflex iliac artery (DCIA) flap is usually used for reconstruction in oral and maxillo-facial surgery department since introduced by O'Brien in 1975. Various flap designs are possible for osteomusculocutaneous, musculocutaneous, musculosseous and vascularized bone types. Iliac crest shape is similar to contour of mandible. Moreover, though a fibular flap has only 15~20 mm of cutting plane width, a DCIA flap contains much more bone amount, making this a similar reconstruction compare with normal mandible. A 68 year-old male with squamous cell carcinoma on the anterior floor of the mouth had an impression with T2N0Mx and the treatment procedure was DCIA reconstruction after wide resection and marginal mandibulectomy, with both supraomohyoid neck dissection. We present an experience of DCIA flap for reconstruction with a literature review.