• Title/Summary/Keyword: symmetrical period

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An Open Space of College Campus according to the Changes of the Times : A Visual Analysis of Cases (대학(大學) 캠퍼스 광장(廣場)의 시대적(時代的) 변천(變遷) : 시각적(視覺的) 사례(事例) 분석(分析))

  • Min, Chang-Kee
    • Journal of the Korean Institute of Educational Facilities
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    • v.9 no.2
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    • pp.25-35
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    • 2002
  • This paper is to evaluate an open space on university campuses enclosed within buildings, with respect to building elevation a wall of an open space including outer wall materials and window forms and an open space itself. It uses case study methods to periodically know specific details about open spaces and surrounding buildings elevation. It was found, at first, that it was emphasized vertical elements on window frames as well as building elements in an era of the 1910's to the 1930's. It, however, was changed into emphasizing on horizontal features in the era of the 1960's to the 1970's. Meanwhile the period from the 1940's to the 1950's was a turning point. The horizontal style was continued until the 1980s and the style was changed into various style mixed with various types. Secondly, an open space was recognized as a valuable design criteria for a construction of buildings in the 1930s to the 1970s. It was, however, a forgotten criteria during the late 1970's and the 1980's because of short age of the construction budget of the government. In the 1990's, the importance of open space design reappeared on the design of a block plan. Thirdly, a design style of an open space was authoritarianism using symmetrical and magnificent style in the 1910's to the 1930's. The time of 1945 to the 1950's was a turning point from authoritarianism to an idea of efficiency. In the 1960's and the 1970s, an idea of efficiency emphasizing their functions was prevalent to the design of buildings and open spaces and this trend was continued until the 1980's. A romanticism was realized on the design of an open space and surrounded building's.

Tide And Tidal Current In The Estuary Of The Nakdong River (낙동강 하구의 조석과 유동)

  • Ryu, Cheong-ro;Chang, Sun-duck
    • 한국해양학회지
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    • v.14 no.2
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    • pp.71-77
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    • 1979
  • Tidal waves and the fluctuation of current are studied by use of observed data on tidal level, flow velocity and river discharge in the estuarine region of the Nakdong River. Observed data on the tidal level at five stations are used to obtain the fluctuation of amplitude and phase of tides, and the change of the wave speed versus distance from the river mouth. Comnining these tidal data with the vertical distribution of horizontal velocity data, some characteristics of the periodic tidal flow are deduced: (1)Diminishing rates of the tidal amplitude ratio η / η$\_$0/ at high tide were 0.058η$\_$0H/ /Km at neap tides. The constant of phase change, K, was 0.035rad/km. (2)While proceeding landward, the shape of the tidal wave changes from symmetrical to asymmetrical. The traveling speed of the tidal wave crest was estimated to be 3.6∼5.2m/sec, while that of the tidal wave trough was 2.4∼ 3.5m/sec. (3)The flowing speed of the water varies periodically in accordance with the tidal period. The maximum speed of landward flow appeared approximately at two hours before the high tide, while that of seaward flow at two hours before the low tide. (4)The upstream boundary is deduced approximately to be 50km at spring tide and 44km at neap tide from the tidal velocity decreasing. the tidal influence area is estimated approximately to be 65km from the tidal amplitude damping.

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Customized Cranioplasty Implants Using Three-Dimensional Printers and Polymethyl-Methacrylate Casting

  • Kim, Bum-Joon;Hong, Ki-Sun;Park, Kyung-Jae;Park, Dong-Hyuk;Chung, Yong-Gu;Kang, Shin-Hyuk
    • Journal of Korean Neurosurgical Society
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    • v.52 no.6
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    • pp.541-546
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    • 2012
  • Objective : The prefabrication of customized cranioplastic implants has been introduced to overcome the difficulties of intra-operative implant molding. The authors present a new technique, which consists of the prefabrication of implant molds using three-dimensional (3D) printers and polymethyl-methacrylate (PMMA) casting. Methods : A total of 16 patients with large skull defects (>100 $cm^2$) underwent cranioplasty between November 2009 and April 2011. For unilateral cranial defects, 3D images of the skull were obtained from preoperative axial 1-mm spiral computed tomography (CT) scans. The image of the implant was generated by a digital subtraction mirror-imaging process using the normal side of the cranium as a model. For bilateral cranial defects, precraniectomy routine spiral CT scan data were merged with postcraniectomy 3D CT images following a smoothing process. Prefabrication of the mold was performed by the 3D printer. Intraoperatively, the PMMA implant was created with the prefabricated mold, and fit into the cranial defect. Results : The median operation time was $184.36{\pm}26.07$ minutes. Postoperative CT scans showed excellent restoration of the symmetrical contours and curvature of the cranium in all cases. The median follow-up period was 23 months (range, 14-28 months). Postoperative infection was developed in one case (6.2%) who had an open wound defect previously. Conclusion : Customized cranioplasty PMMA implants using 3D printer may be a useful technique for the reconstruction of various cranial defects.

THE EFFECT OF PRE-OPERATIVE STEROID INJECTION ON THE RELIEF OF COMPLAINT AFTER THIRD MOLAR SURGERY (술 전 스테로이드 투여가 하악 매복 제 3 대구치 발치 후 예상되는 불편감에 미치는 영향)

  • Kim, Sung-Dae;Kim, Kyung-Wook
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.29 no.3
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    • pp.157-162
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    • 2003
  • Background : The surgical removal of impacted mandibular third molar can result in considerable pain, swelling, and dysfunction that patient are incapable of work for several days. Factors contributing to post operative swelling, trismus and pain are complex. There is no question but that the procedure of surgically removing an impacted mandibular third molar is inherently a traumatic one and that some sequelae related to the inflammation response are expected. Meticulous surgical technique will minimize the sequelae of inflammation but will not prevent them. In an effort to minimize these sequelae the use of steroid was instituted. Patients and Methods : Present study was to investigate the effect of one preoperative steroid injection in the masseter muscle to the patients(male 9, female 11) who needed prophylactic removal of bilateral, symmetrical, impacted wisdom teeth in the mandible on the complaint like swelling, trismus and pain. through Double-Blind test. Results : 1. After 24 hours investigation, preoperative steroid injection had significantly reduced swelling with 39% and trismus with 57.5%. 2. $7^{th}$ post operative day investigation, reduced swelling and trismus had shown, however, not significant. 3. There wasn't major difference from the group who took preve-ntive steroid in the visual analogue scale, the first analgesic intake time and the pain period. 4. There wasn't any adverse reaction of steroid for 20 patient From the above result, If the patients are not contraindication to steroid and pronounced post operative reaction can be expected the use of steroid to the surgical removal of impacted mandibular third molar is recommended.

Symmetrical Multipartite of Lateral Fabella in a Small Breed Dog (소형견에서 외측 무릎 종자뼈의 대칭적 다분화)

  • Cho, Young-Kwon;Lee, Ki-Chang
    • Journal of Veterinary Clinics
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    • v.26 no.6
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    • pp.655-658
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    • 2009
  • An 11-year-old, female, Maltese dog was presented with abdominal distension and intermittent slight lameness on left hindlimb. Palpable abdominal pain and purulent vaginal discharge were observed on physical examination. Severe leukopenia with toxic change, and azotemia, hyperphosphatemia, and hyponatremia were identified on blood profile. On radiographs and abdominal sonograms, remarkable soft tissue mass containing echogenic material deviating intestines craniodorsally compatible with pyometra. On stifle radiographs, 4-5 fragmented sesamoid bone (fabella) was identified on both stifle joint with medial patella luxation. Immediate ovariohysterectomy was performed and the patient was recovered well with normal blood work. No specific treatment was attempted to the left hindlimb showing minimal and intermittent lameness. No remarkable abnormal gait was reported for 3-month follow-up period. The fragmented lateral fabella is considered congenital multipartite of lateral fabella not related to the lameness.

Three-dimensional assessment of the temporomandibular joint and mandibular dimensions after early correction of the maxillary arch form in patients with Class II division 1 or division 2 malocclusion

  • Coskuner, Hande Gorucu;Ciger, Semra
    • The korean journal of orthodontics
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    • v.45 no.3
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    • pp.121-129
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    • 2015
  • Objective: This study aimed to assess three-dimensional changes in the temporomandibular joint positions and mandibular dimensions after correction of dental factors restricting mandibular growth in patients with Class II division 1 or division 2 malocclusion in the pubertal growth period. Methods: This prospective clinical study included 14 patients each with Class II division 1 (group I) and Class II division 2 (group II) malocclusions. The quad-helix was used for maxillary expansion, while utility arches were used for intrusion (group I) or protrusion and intrusion (group II) of the maxillary incisors. After approximately 2 months of treatment, an adequate maxillary arch width and acceptable maxillary incisor inclination were obtained. The patients were followed for an average of 6 months. Intraoral and extraoral photographs, plaster models, and cone-beam computed tomography (CBCT) images were obtained before and after treatment. Lateral cephalometric and temporomandibular joint measurements were made from the CBCT images. Results: The mandibular dimensions increased in both groups, although mandibular positional changes were also found in group II. There were no differences in the condylar position within the mandibular fossa or the condylar dimensions. The mandibular fossa depth and condylar positions were symmetrical at treatment initiation and completion. Conclusions: Class II malocclusion can be partially corrected by achieving an ideal maxillary arch form, particularly in patients with Class II division 2 malocclusion. Restrictions of the mandible in the transverse or sagittal plane do not affect the temporomandibular joint positions in these patients because of the high adaptability of this joint.

A comparative study of periodontal conditions around mesially tipped molars by a tipping degree (치주질환으로 인한 예후 불량 치아의 분포)

  • Kang, Young-Hwa;Kim, Sung-Ho;Jeon, Yong-Seon;Chang, Moon-Taek;Kim, Hyung-Seop
    • Journal of Periodontal and Implant Science
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    • v.32 no.1
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    • pp.51-59
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    • 2002
  • The aim of the present study was to investigate the distribution of periodontally hopeless teeth in patients who had not been treated. Five hundred nineteen teeth of 163 patients who had visited at the Department of Periodontology, Chonbuk National University Hospital during the period from January 1999 to July 2001 were selected as a periodontally hopeless tooth. Selection criteria were as follows: 1) probing pocket depth more than 8mm, 2) tooth mobility of degree III, 3) radiographic bone loss more than 75%. The contralateral tooth to a hopeless tooth (experimental tooth) was designated as a control tooth. Between the experimental and control tooth, differences in probing pocket depth, tooth mobility and amount of radiographic bone loss were examined as well as correlation. The results showed that hopeless teeth were most frequently found in the maxillary first molar position and least frequently in the maxillary canine position. Differences between experimental and control teeth were 2mm in probing depth, 1 degree in tooth mobility, and 20% in amount of bone loss (p<0.01). The periodontal conditions between the experimental and control teeth showed correlation in general, however, statistical significances were found in posterior teeth positions. Within limitations of this study, it can be concluded that local factors may play a role in deterioration of periodontal disease along with symmetrical character of periodontal disease.

Assessment of stem cell viability in the initial healing period in rabbits with a cranial bone defect according to the type and form of scaffold

  • Kang, Seung-Hwan;Park, Jun-Beom;Kim, InSoo;Lee, Won;Kim, Heesung
    • Journal of Periodontal and Implant Science
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    • v.49 no.4
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    • pp.258-267
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    • 2019
  • Purpose: Increased bone regeneration has been achieved through the use of stem cells in combination with graft material. However, the survival of transplanted stem cells remains a major concern. The purpose of this study was to evaluate the viability of transplanted mesenchymal stem cells (MSCs) at an early time point (24 hours) based on the type and form of the scaffold used, including type I collagen membrane and synthetic bone. Methods: The stem cells were obtained from the periosteum of the otherwise healthy dental patients. Four symmetrical circular defects measuring 6 mm in diameter were made in New Zealand white rabbits using a trephine drill. The defects were grafted with 1) synthetic bone (${\beta}$-tricalcium phosphate/hydroxyapatite [${\beta}-TCP/HA$]) and $1{\times}10^5MSCs$, 2) collagen membrane and $1{\times}10^5MSCs$, 3) ${\beta}-TCP/HA+collagen$ membrane and $1{\times}10^5MSCs$, or 4) ${\beta}-TCP/HA$, a chipped collagen membrane and $1{\times}10^5MSCs$. Cellular viability and the cell migration rate were analyzed. Results: Cells were easily separated from the collagen membrane, but not from synthetic bone. The number of stem cells attached to synthetic bone in groups 1, 3, and 4 seemed to be similar. Cellular viability in group 2 was significantly higher than in the other groups (P<0.05). The cell migration rate was highest in group 2, but this difference was not statistically significant (P>0.05). Conclusions: This study showed that stem cells can be applied when a membrane is used as a scaffold under no or minimal pressure. When space maintenance is needed, stem cells can be loaded onto synthetic bone with a chipped membrane to enhance the survival rate.

A Study on the Feng Shui Environment of Simgok Seowon (심곡서원의 풍수 환경연구)

  • Duck-Soo Choi;Jeong-Hae Park
    • Industry Promotion Research
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    • v.8 no.3
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    • pp.163-174
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    • 2023
  • Simgok Seowon was established to honor Jo Gwang-jo, who is a scholar and politician in the mid-Joseon period. It is located in a propitious site based on Feng Shui. Its Jusan is Mugokeumseongchae(武曲金星體) with Wonhwahyul(圓窩穴), and its Ansan is Tamrangmokseongchae(貪狼木星體). It is a Jehyang(祭享)-centered Seowon that sets a Jehyang place in Hyeolcheo. Around the Sadang(祠堂), the Four gods including Jwacheongryong(左靑龍) Woobackho(右白虎), Jujak(朱雀), and Hyeonmu(玄武) protect the Hyeolcheo(穴處) well. It is a typical central axis symmetrical spatial arrangement where everything is located centered on Sawoo(祠宇). It is a type of Jeonhakhumyo(前學後廟) that arranges the main hall at the front of buildings and places the Sadang that is a Jehyang place at the back of Sadang. To the left side of the Sadang, Yeonji(蓮池) was created by applying the principles of Cheonwonjibang(天圓地方), which serves as Yusik(遊息) area with functions to adjust microclimate and to extinguish fires. Feng Shui plays an important role when determining orientation, direction, and location of the buildings. Therefore, it could be regarded as realizing the aesthetic spirit of Cheoninhabil(天人合一) to compose the Feng Shui-oriented spatial arrangement by recognizing accurately the relationship between nature and human being depending on topography, wind, water flow, and point of the compass.

Evaluation of the regenerative capacity of stem cells combined with bone graft material and collagen matrix using a rabbit calvarial defect model

  • Jun-Beom Park;InSoo Kim;Won Lee;Heesung Kim
    • Journal of Periodontal and Implant Science
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    • v.53 no.6
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    • pp.467-477
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    • 2023
  • Purpose: The purpose of this study was to evaluate the regenerative capacity of stem cells combined with bone graft material and a collagen matrix in rabbit calvarial defect models according to the type and form of the scaffolds, which included type I collagen matrix and synthetic bone. Methods: Mesenchymal stem cells (MSCs) were obtained from the periosteum of participants. Four symmetrical 6-mm-diameter circular defects were made in New Zealand white rabbits using a trephine drill. The defects were grafted with (1) group 1: synthetic bone (β-tricalcium phosphate/hydroxyapatite [β-TCP/HA]) and 1×105 MSCs; (2) group 2: collagen matrix and 1×105 MSCs; (3) group 3: β-TCP/HA, collagen matrix covering β-TCP/HA, and 1×105 MSCs; or (4) group 4: β-TCP/HA, chipped collagen matrix mixed with β-TCP/HA, and 1×105 MSCs. Cellular viability and cell migration rates were analyzed. Results: Uneventful healing was achieved in all areas where the defects were made at 4 weeks, and no signs of infection were identified during the healing period or at the time of retrieval. New bone formation was more evident in groups 3 and 4 than in the other groups. A densitometric analysis of the calvarium at 8 weeks post-surgery showed the highest values in group 3. Conclusions: This study showed that the highest regeneration was found when the stem cells were applied to synthetic bone along with a collagen matrix.