DETECTING INFLUENTIAL SUBSETS IN REGRESSION ANALYSIS BY MEANS OF CLUSTER ANALYSIS

TANAKA, Yutaka,ODAKA, Yoshimasa,MOON, Sung Ho 高麗大學校統計硏究所 1992 應用統計 Vol.7 No.-

본 논문은 회귀분석에 있어서의 influential subsets의 탐색에 관하여 논한다. 이를 위하여 Moon, Yanagi and Tanaka(1992)에 의해 제안된 계층적 군집 알고리즘을 적용하였다. 이 알고리즘은 경험 영향력 함수(EIF)가 이용가능한 다변량 해석법에 있어서의 influential subsets을 탐색하기 위한 일반적인 방법의 하나로서 고안된 것이다. 또한 이를 위하여 일반화 영향력 함수(generalized influence function)를 유도하게 되며, 몇가지 유형의 영향력 측면 - 즉, 추정치와 추정치의 정도(精度)에 대한 영향 - 에서 정의되는 군집간의 유사성을 이용하였다. 이 논문의 주된 목적은 앞의 연구에 의한 알고리즘을 회귀분석에 적용하여 기존의 multiple case 진단법과의 결과 비교를 통하여 그것의 효율성을 논하는 데 있다.

A safe, stable, and convenient three-dimensional device for high Le Fort I osteotomy

Sugahara, Keisuke,Koyachi, Masahide,Odaka, Kento,Matsunaga, Satoru,Katakura, Akira Korean Association of Maxillofacial Plastic and Re 2020 Maxillofacial Plastic Reconstructive Surgery Vol.42 No.-

Background: Le Fort I osteotomy is a highly effective treatment for skeletal jaw deformities and is commonly performed. High Le Fort I osteotomy is a modified surgical procedure performed for improving the depression of the cheeks by setting the osteotomy higher than the conventional Le Fort I osteotomy. Developments in three-dimensional (3D) technology have popularized the use of 3D printers in various institutions, especially in orthognathic surgeries. In this study, we report a safe and inexpensive method of performing a high Le Fort I osteotomy using a novel 3D device and piezosurgery, which prevent tooth root injury without disturbing the operation field for patients with a short midface and long tooth roots. Results: A 17-year-old woman presented with facial asymmetry, mandibular protrusion, a short midface, and long tooth roots. We planned high Le Fort I osteotomy and bilateral sagittal split ramus osteotomy. Prevention of damage to the roots of the teeth and the infraorbital nerve and accurate determination of the posterior osteotomy line were crucial for clinical success. Le Fort I osteotomy using 3D devices has been reported previously but were particularly large in size for this case. Additionally, setting the fixing screw of the device was difficult, because of the risk of damage to the roots of the teeth. Therefore, a different surgical technique, other than the conventional Le Fort I osteotomy and 3D device, was required. The left and right parts of the 3D device were fabricated separately, to prevent any interference in the surgical field. Further, the 3D device was designed to accurately cover the bone surface from the piriform aperture to the infra-zygomatic crest with two fixation points (the anterior nasal spine and the piriform aperture), which ensured stabilization of the 3D device. The device is thin and does not interfere with the surgical field. Safe and accurate surgical performance is possible using this device and piezosurgery. The roots of the teeth and the infraorbital nerve were unharmed during the surgery. Conclusions: This device is considerably smaller than conventional devices and is a simple, low-cost, and efficient method for performing accurate high Le Fort I osteotomy.

DETECTING INFLUENTIAL SUBSETS IN REGRESSION ANALYSIS BY MEANS OF CLUSTER. ANALYSIS

Sung Ho MOON,Yoshimasa ODAKA,Yutaka TANAKA 고려대학교 통계연구소 1992 應用統計 Vol.7 No.-

Variation analysis of free-style hand-written character pattern in documents

Yoshimasa Kimura,Kazumi Odaka 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

We investigated variation analysis of individual character pattern written in free style and introduce ouranalysis strategy that combines five characteristics guessed to influence character variation and four types of analysis methods. The position of character, the order of writing the character, the writing time, writing pressure, etc. were selected as the five characteristics and the four analysis methods are constituted from an analysis of individualcharacteristics, relations between each characteristic, etc. Results of the analysis for collected characters show the writing time strongly influences the variation of character pattern.

Maxillary reconstruction using tunneling flap technique with 3D custom-made titanium mesh plate and particulate cancellous bone and marrow graft: a case report

Takano, Masayuki,Sugahara, Keisuke,Koyachi, Masahide,Odaka, Kento,Matsunaga, Satoru,Homma, Shinya,Abe, Shinichi,Katakura, Akira,Shibahara, Takahiko Korean Association of Maxillofacial Plastic and Re 2019 Maxillofacial Plastic Reconstructive Surgery Vol.41 No.-

Background: Reconstructive surgery is often required for tumors of the oral and maxillofacial region, irrespective of whether they are benign or malignant, the area involved, and the tumor size. Recently, three-dimensional (3D) models are increasingly used in reconstructive surgery. However, these models have rarely been adapted for the fabrication of custom-made reconstruction materials. In this report, we present a case of maxillary reconstruction using a laboratory-engineered, custom-made mesh plate from a 3D model. Case presentation: The patient was a 56-year-old female, who had undergone maxillary resection in 2011 for intraoral squamous cell carcinoma that presented as a swelling of the anterior maxillary gingiva. Five years later, there was no recurrence of the malignant tumor and a maxillary reconstruction was planned. Computed tomography (CT) revealed a large bony defect in the dental-alveolar area of the anterior maxilla. Using the CT data, a 3D model of the maxilla was prepared, and the site of reconstruction determined. A custom-made mesh plate was fabricated using the 3D model (Okada Medical Supply, Tokyo, Japan). We performed the reconstruction using the custom-made titanium mesh plate and the particulate cancellous bone and marrow graft from her iliac bone. We employed the tunneling flap technique without alveolar crest incision, to prevent surgical wound dehiscence, mesh exposure, and alveolar bone loss. Ten months later, three dental implants were inserted in the graft. Before the final crown setting, we performed a gingivoplasty with palate mucosal graft. The patient has expressed total satisfaction with both the functional and esthetic outcomes of the procedure. Conclusion: We have successfully performed a maxillary and dental reconstruction using a custom-made, pre-bent titanium mesh plate.

Novel condylar repositioning method for 3D-printed models

Sugahara, Keisuke,Katsumi, Yoshiharu,Koyachi, Masahide,Koyama, Yu,Matsunaga, Satoru,Odaka, Kento,Abe, Shinichi,Takano, Masayuki,Katakura, Akira Korean Association of Maxillofacial Plastic and Re 2018 Maxillofacial Plastic Reconstructive Surgery Vol.40 No.-

Background: Along with the advances in technology of three-dimensional (3D) printer, it became a possible to make more precise patient-specific 3D model in the various fields including oral and maxillofacial surgery. When creating 3D models of the mandible and maxilla, it is easier to make a single unit with a fused temporomandibular joint, though this results in poor operability of the model. However, while models created with a separate mandible and maxilla have operability, it can be difficult to fully restore the position of the condylar after simulation. The purpose of this study is to introduce and asses the novel condylar repositioning method in 3D model preoperational simulation. Methods: Our novel condylar repositioning method is simple to apply two irregularities in 3D models. Three oral surgeons measured and evaluated one linear distance and two angles in 3D models. Results: This study included two patients who underwent sagittal split ramus osteotomy (SSRO) and two benign tumor patients who underwent segmental mandibulectomy and immediate reconstruction. For each SSRO case, the mandibular condyles were designed to be convex and the glenoid cavities were designed to be concave. For the benign tumor cases, the margins on the resection side, including the joint portions, were designed to be convex, and the resection margin was designed to be concave. The distance from the mandibular ramus to the tip of the maxillary canine, the angle created by joining the inferior edge of the orbit to the tip of the maxillary canine and the ramus, the angle created by the lines from the base of the mentum to the endpoint of the condyle, and the angle between the most lateral point of the condyle and the most medial point of the condyle were measured before and after simulations. Near-complete matches were observed for all items measured before and after model simulations of surgery in all jaw deformity and reconstruction cases. Conclusions: We demonstrated that 3D models manufactured using our method can be applied to simulations and fully restore the position of the condyle without the need for special devices.

New method to measure whole-wavelength transmittance of TCO substrates for thin-film silicon solar cells

Masanobu Isshiki,Porponth Sichanugrist,Yusuke Abe,Takuji Oyama,Hidefumi Odaka,Makoto Konagai 한국물리학회 2014 Current Applied Physics Vol.14 No.12

High transmittance of transparent conductive oxide (TCO) substrates is one of the most important factors for achieving high efficiency in thin-film silicon solar cells. Immersion (IM) method with CH2I2 liquid is widely used for the evaluation of optical properties (transmittance, reflectance and absorption) for TCO substrates with textured surface in order to reduce the scattering at the TCO surface. However, in order to measure transmittance accurately, three problems have been found. (1) CH2I2 liquid itself absorbs the light in short wavelength region. (2) The transmittance around the absorption edge of CH2I2 liquids is very sensitive to its amount. (3) Scattering cannot be suppressed when the scattering surfaces are more than 2 surfaces (for example, TCO on reactive ion etching (RIE) processed glass). To overcome these problems, we proposed a new setup to measure optical properties of TCO substrates by holding the samples inside the integral sphere. As the results, we have confirmed that their absorption in all wavelength could be measured accurately and the transmittance measured by the new method was well consistent with the external quantum efficiency (EQE) of the fabricated cell while the transmittance measured with conventional IM method showed differently. Therefore, this new method could be a useful tool to evaluate TCO substrates for thin-film silicon solar cells.

CO₂가스첨가에 의한 배기가스 및 연소 특성해석에 관한 연구

엄종호(J.H.UHM),정동수(D.S.JEONG),소지장개(N.KOIKE),소고송남(M>ODAKA) 한국자동차공학회 1993 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

It was recognized that NOx emission and smoke were reduced remarkably with changing the O₂ concentration of intake charge due to adding CO₂ gas and<br/> by controlling injection timing property with the O₂concentration. In (his study<br/> exhaust emissions were analyzed with the combustion characteristics calculated<br/> from cylinder pressure on the O₂ concentration and injection timing for a single cyliner DI diesel engine. To compare the analysis of combustion characteristics<br/> direct combustion photography using by high speed video camera with the O₂<br/> concentration and different injection timing were taken.<br/> <br/> Keyword: NOx Emission, CO2 Gas Addition, Fuel Injection Timing, High Speed Digital Camera, Direct Combustion Photography<br/>