• The Journal of Engineering Geology
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• v.3 no.3
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• pp.279-293
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• 1993

In recent yeaes, the collapses of man made structures have been encountered from time to time due to the deformation of the ground in korea. Furthermore, the possibilities of casasters from the ground deformation suCh as landslide and active fault are atrracting our attention to the deformation monitoring. In this study, two-coordinate tilt which was monitored during six months in order to develop tediniques for prevention of disasters from the ground deformation. The two-coordinate tilt which was detected by a tilt-sensor installed in shallow depth on the slope with the sensitivity of 0.0001 arc.sec in every 10 minutes was recorded continously to PC through the interface with 200-m line coonection. The observed digital tilt data. together with the relevant meteorological data were analyzed in reference to engineering application. During the whole observation period of six months, the net tilt is 10.06 arc.sec to the west and 73.88 arc.sec to the south. Consequently the ground has a tilt of 74.56 arc.sec to the direction of $S7.75^{\circ}W$ with average tilting of 0.02 arc.sec/hour. In spite of such fast and large tilting, it is interpreted in view of engineering aspects that the site is much safe from danger, since both East-West and North-South components of tilt converge as time goes by. Two categories of deformational events are recognized ; one is toward the direction of surface slope and the other is to the direction of increased pore pressure. Tiks are acenain to have a close relation with precipitation of rain. The daily variation of two-coordinate tilt is delayed 4.3 hours in average after the variation of atmospheric temperature. A certain correlation between atmospheric pressure and deformation might be revealed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.6
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• pp.501-508
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• 2005

Generally we use the preauricular incision to access and remove the parotid gland tumor. But the preauricular approach has some complications such as damage of facial nerve and sensory nerve, Frey's syndrome, and postoperative scar. Especially, the postoperative scar can often cause an unesthetic result and mental stress in young patients. Therefore, if we avoid preauricular incision to be performed outside of tragus, the postoperative scar would be hardly remarkable, and patients would be satisfied cosmetically. We performed surgical excision using a modified endaural and neck approach in a 21-year-old female with a pleomorphic adenoma and 15-year-old male with a neurofibroma occured in the parotid gland. A new, modified endaural and neck approach is a combined method of the modified endaural incision by Starck et al and Gutierrez's neck extension. We obtained an adequate access and the cosmetically acceptable postsurgical scar. The postoperative scars were hidden in the external ear and the hairline. Moreover, except the neck dissection can this approach be applied to the surgery of temporomandibular joint as well as the parotid gland tumor.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.2
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• pp.167-173
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• 2007

The temporalis fascia graft has been widely used in the correction of nasal deformities. The fascia can be used alone or combined for augmentation rhinoplasty. The fascia graft provides adequate coverage, contour, and bulk on the profile of the nose, as well as an inconspicuous donor site. A depressed radix area can be successfully corrected by the fascia graft. We present two cases of nasal radix augmentation by using temporalis fascia graft. Two male patients presented with the skeletal class III malocclusion and the depressed radix. A planned orthognathic surgery and the temporalis fascia graft to the radix were performed. The malocclusion and the profile of the patients were markedly improved after the operation. Not only the radix but also the nose was improved in its size and length. There was no noticeable resorption or displacement of the radix area at follow-up. The temporalis fascia graft could be an appropriate surgical technique in radix augmentation and nose lengthening.

• Journal of the Korean Society of Radiology
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• v.10 no.8
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• pp.571-576
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• 2016

3D printing has recently been used in various fields. Among various applications, 3D face data must be generated for 3D face printing. A laser scanner is used to acquire 3D face data, but there is a restriction that a person should not move during scanning. In this paper, we propose a 3D face modeling method based on a single image and a face transformation system to use the generated 3D face for virtual cosmetic surgery. We have defined facial feature points from the 3D face database for 3D face data generation. After extracting feature points from a single face image, 3D face of the input face image is generated corresponding to the 3D face feature points defined from the 3D face database. After 3D face modeling, 3D face modification part is applied for use such as virtual cosmetic surgery.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.4 no.3
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• pp.161-167
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• 1992

We consider the preparation of long finite amplitude nondispersive waves over a step bottom between two regions of finite different depths. Two dimensional motion is assumed. with the wave crests parallel to the step, and irrotational flow in the inviscid fluid is considered. To describe the transformation of finite amplitude waves we use the finite-amplitude shallow-water equations, the conditions of mass flow conservation and pressure continuity at the cut above the step in Riemann's variables. The equations define four families of curves-characteristics on which the values of the Riemann's invariants remain constant and a system of two nonlinear equations that relates the amplitudes of incident reflected and transmitted waves. The system obtained is difficult to analyze in common form. Thus we consider some special cases having practical usage for tsunami waves. The results obtained are compared with the long wave theory and significant nonlinear effects are found even for quite small amplitude waves.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.1
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• pp.55-62
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• 2007

Radical paring of the cleft edge during primary cleft lip operation or repeated secondary surgeries can result in tightness of the upper lip. In case, the degree of the resulting side-to-side tension is very severe, the possibility of a lip switch flap must be considered. When the lip tightness accompanies a loss of more than two-thirds of the Cupid's bow, an Abbe flap is an alternative. The disadvantages of Abbe flap are scar formation on the lower lip, design of incision line on the upper lip, disharmony of colors, and the dysfunction of the orbicularis muscle. These problems have been recognized in the literature and extreme discretion has been advised in its application. We experienced four cases of Abbe flap operation which were designed differently to correct the secondary unilateral or bilateral cleft-lip nasal deformities. The Abbe flap operations resulted in removal of the scars and tightness of the upper lip, reconstruction of the Cupid's bow, lengthening of the columella, and therefore secondary cleft-lip nasal deformity could be corrected. It is thought that carefully applied Abbe flap is an appropriate method to relieve horizontal tightness or flattening of the upper lip which occured after primary operation of cleft lip.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.1
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• pp.54-60
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• 2001

The treatment of maxillary cancer has been commonly performed by the surgery and radiation therapy, alone or in combination. Multimodal treatment has been introduced with improvement of chemotherapy and immunotherapy. Multimodal treatment for the maxillary cancer is composed of surgery, radiation therapy, and regional intra-arterial chemotherapy. The present study was performed to evaluate the effectiveness of the multimodal treatment with Morita's method, with a slight modification, for the maxillary cancer. Twenty-four cases of the maxillary cancer were analyzed. The multimodal treatment increased the 5-year-survival rate up to 66% and reduced the need for maxillectomy. This method made the morphological and funtional preservation possible. This method may be recommended for the treatment of maxillary cancer.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.566-570
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• 2012

본 연구에서는 비선형 k-$\varepsilon$ 모형을 이용하여 직사각형 개수로에서 평균흐름과 난류구조를 모의하였다. 표준 k-$\varepsilon$ 난류모형은 난류의 등방성을 가정하여 국부적 평형상태에서 계산하기 때문에 유선에 따른 레이놀즈 응력의 변형이 큰 경우나 이방성이 강한 경우 이를 계산하지 못한다. 이를 보완하기 위하여 제시된 것이 비선형 k-$\varepsilon$ 난류모형이다. 본 연구에서는 표준 k-$\varepsilon$ 모형과 비선형 k-$\varepsilon$ 모형에 의한 모의결과를 비교하였다. 난류모형을 검증하기 위하여 직사각형 개수로에 흐름을 완전 발달된 등류로 가정하여 해석하였다. 지배방정식을 해석하기 위해 Patankar와 Spalding (1972)이 제시한 SIMPLER 알고리즘을 사용하였고 유한체적법을 이용하여 이산화하고 엇갈린 격자체계를 사용하여 계산에서 발생하는 과도한 진동을 줄였다. 또한 차분기법은 Patankar (1980)가 제시한 Power-law 기법을 채택하였으며 경계조건으로 2층 벽법칙 모형과 Hossain과 Rodi (1993)의 모형을 이용하였다. 두 모형의 적용성을 검증하기 위하여 실측자료를 이용하여 비교하였고 그 결과 비선형 k-$\varepsilon$ 모형이 표준 k-$\varepsilon$ 모형에 비해 좀 더 실측지에 가깝게 모의하는 것을 볼 수 있었다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.1
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• pp.1-9
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• 2009

OFDM(Orthogonal Frequency Division Multiplexing) system is robust to frequency selective fading and narrowband interference in high-speed data communications. However, an OPDM signal consists of a number of independently modulated subcarriers and the superposition of these subcarriers causes a problem that can give a large PARR(Peak-to-Average Power Ratio). PTS(Partial Transmit Sequence) scheme can reduce the PAPR by dividing OFDM signal into subblocks and then multiplying the phase weighting factors to each subblocks, but computational complexity for selecting of phase weighting factors increases exponentially with the number of subblocks. Therefore, in this paper, MG-PSO(Modified Greedy algorithm-Particle Swarm Optimization) algorithm that combines modified greedy algorithm and PSO(Particle Swarm Optimization) algorithm is proposed to use for the phase control method in PTS scheme. This method can solve the computational complexity and guarantee to reduce PAPR. We analyzed the performance of the PAPR reduction when we applied the proposed method to telecommunication systems.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.3
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• pp.247-253
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• 2006

Pleomorphic adenoma of the parotid gland typically presents as painless, mobile mass of long duration, and originate in the superficial lobe but, more rarely these tumors may involve the deep lobe of the parotid gland. The average size of a parotid neoplasm is 2 to 4 cm. The effective treatment of parotid pleomorphic adenoma is surgical excision. The simple excision or enucleation resulted in recurrence rate of 45% in benign tumor. Therefore, the superficial parotidectomy with identification and preservation of the facial nerve is now the most widely accepted surgery. We report a case of the huge pleomorphic adenoma of the left parotid gland in a 67-year-old man who complained the large mass, measured about $10\times7\times5$cm-sized, in front of the left ear and on the mandibular ascending ramus. The diagnosis was confirmed by the clinical examination, computed tomographic scan, fine needle aspiration, and incisional biopsy. Superficial parotidectomy including the tumor and preservation of the facial nerve using the modified Blair approach was performed. And satisfactory results have been obtained cosmetically and functionally.