• Archives of Plastic Surgery
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• 제32권3호
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• pp.287-292
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• 2005

The definitive correction of secondary lip nasal deformities is a great challenge for plastic surgeons. To rectify the secondary lip nasal deformities, various procedures and its modifications have been reported in many centers. However, no universal agreement exist to correct the various components of secondary nasal deformities. The secondary nasal deformity of the unilateral cleft lip has its own characteristic abnormalities including the retroplaced dome of the ipsilateral nasal tip, hooding of the alar rim, a secondary alar-columellar web, short columella, depressed alar base and so forth. Among these components of secondary nasal deformity, maxillary hypoplasia, especially in the area of piriform aperture, and alveolar bone defect can make the alar base depressed, which in turn, leads to wide and flat nasal profile, obtuse nasolabial angle coupled with subnormal nasal tip projection in aspect of aesthetic consideration. Moreover, the maxillary hypoplasia contributes to reduced size of the nasal airway in combination with other component of external nasal deformity and therefore the nasal obstruction may be developed functionally. Therefore, the current authors have performed corrective rhinoplasty with the augmentation of alar base with various methods which include rearrangement of soft tissue, vertical scar tissue flap and use of allogenic or autologous materials in 42 patients between 1998 and 2003. The symmetric alar base could be achieved, which provides the more accurate evaluation and more appropriate management of the various component of any coexisting secondary nasal deformity. In conclusion, the augmentation of alar base, as a single procedure, is a basic and essential to correct the secondary lip nasal deformities.

• Journal of Communications and Networks
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• 제16권1호
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• pp.67-80
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• 2014

Spectrum sensing is vital for secondary unlicensed nodes to coexist and avoid interference with the primary licensed users in cognitive wireless networks. In this paper, we develop models for bounding interference levels from secondary network to the primary nodes within a spectrum sensing framework. Instead of classical stochastic approaches where Poisson point processes are used to model transmitters, we consider a more practical model which takes into account the medium access control regulations and where the secondary Poisson process is judiciously thinned in two phases to avoid interference with the secondary as well as the primary nodes. The resulting process will be a modified version of the Mat$\acute{e}$rn point process. For this model, we obtain bounds for the complementary cumulative distribution function of interference and present simulation results which show the developed analytical bounds are quite tight. Moreover, we use these bounds to find the operation regions of the secondary network such that the interference constraint is satisfied on receiving primary nodes. We then obtain theoretical results on the primary and secondary throughputs and find the throughput limits under the interference constraint.

• 한국환경보건학회지
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• 제26권3호
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• pp.61-68
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• 2000

The use of photo-catalytic processes in pollution abatement and resource has a significant economic importance. Therefore, the applications of photochemical oxidation of secondary effluent driven by UV, TiO2, TiO2/UV, H2O2/UV and TiO2/H2O2/UV, have been investigated in order to treat the secondary effluent from municipal sewage. Various experimental parameters such as BOD, CODcr, Nurbidity, total P, and SPC were examined in each photo-catalytic reaction system. The results showed that the application of single oxidant such as UV, TiO2 only has a minor effect on parameters reduction (CODcr, BOD, etc) to treat the secondary effluent, whereas the combinations of oxidants increase the removal efficiency. The best removal efficiency in every parameters was achieved by the combination of TiO2, H2O2 and UV. It was also found that the optimum amount of TiO2 for the treatment was 1g/ι to achieve water reuse standard. From the results, the photocatalytic reaction system can be an alternative as a post-treatment to treat the secondary effluent from municipal sewage.

• International Journal of Computer Science & Network Security
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• 제22권8호
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• pp.292-298
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• 2022

The study aimed to measure the effectiveness of using Cognitive virtual tours based on Marzano model to develop the achievement and some of historical research Skills for secondary school students. To achieve the objectives of the study, the experimental method was used and two study groups consisted of (60) students were divided into two groups, one is Control (30) students and the other is in experimental (30) students at Alsalam secondary in Ismailia Governorate. The study used several tools: The experimental processing tool of Cognitive Virtual tours based on Marzano model, Cognitive achievement test for the first unit of Secondary first grade history Course. Historical research skills. The finding of the study showed the effectiveness of using cognitive virtual tours based on Marzano model in developing the achievement and some of historical research skills for first grade secondary students which there are Statistically differences at level (0.01) between the average scores of the students in (experimental and Control) groups in post application for Cognitive achievement test. Practical application of the study can contribute to clarify how to use Cognitive virtual tours based on Marzano model in teaching history, and Draw the attention of history developers to the development of historical research skills.

• Journal of Communications and Networks
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• 제11권2호
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• pp.175-186
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• 2009

A new medium access control (MAC) scheme embedding physical channels into multiband carrier sense multiple access/collision avoidance (CSMA/CA) networks is proposed to provide strict quality of service (QoS) guarantee to high priority users. In the proposed scheme, two priority classes of users, primary and secondary users, are supported. For primary users physical channels are provided to ensure strict QoS, whereas secondary users are provided with best-effort service using CSMA/CA modified for multiband operation. The performance of the proposed MAC scheme is investigated using a new multiband CSMA/CA Markov chain model capturing the primary user activity and the operation of secondary users in multiple bands. The throughput of secondary users is obtained as a function of the primary user activity and other CSMA/CA parameters. It is shown that the new MAC scheme yields larger throughput than the conventional single-band CSMA/CA when both schemes use the same bandwidth.

• Journal of Power Electronics
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• 제14권6호
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• pp.1224-1232
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• 2014

A full-bridge secondary dual-resonant DC-DC converter using the asymmetrical pulse-width modulated (APWM) strategy is proposed in this paper. The proposed converter achieves zero-voltage switching for the power switches and zero-current switching for the rectifier diodes in the whole load range without the help of any auxiliary circuit. Given the use of the APWM strategy, a circulating current that exists in a traditional phase-shift full-bridge converter is eliminated. The voltage stress of secondary rectifier diodes in the proposed converter is also clamped to the output voltage. Thus, the existing voltage oscillation of diodes in traditional PSFB converters is eliminated. This paper presents the circuit configuration of the proposed converter and analyzes its operating principle. Experimental results of a 1 kW 385 V/48 V prototype are presented to verify the analysis results of the proposed converter.

• 대한기계학회논문집A
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• 제30권12호
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• pp.1626-1633
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• 2006

In the present paper, in the context of the meshless interpolation of a moving least squares (MLS) type, a novel method which uses primary and secondary nodes in the domain and on the global boundary is introduced, in order to improve the accuracy of solution. The secondary nodes can be placed at any location where one needs to obtain a better resolution. The support domains for the shape functions in the MLS approximation are defined from the primary nodes, and the secondary nodes use the same support domains. The shape functions based on the MLS approximation, in an integration domain, have a single type of a rational function, which reduces the difficulty of numerical integration to evaluate the weak form. The present method is very useful in an adaptive calculation, because the secondary nodes can be easily added and moved without an additional mesh. Several numerical examples are presented to illustrate the effectiveness of the present method.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제21권2호
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• pp.198-204
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• 1999

The treatment of cleft lip and palate patients requires multidisciplinary coorperation, and the involved clinicians rely on the completeness and accuracy of the patient's medical records in developing comprehensive treatment plans. There are so many classifications in cleft lip and palate but each classification has advantages and disadvantages. Furthermore there are few classification or assessment in secondary cleft lip and palate deformities. A modification of Kenahan's Y classification in primary cleft lip and palate and new classification in secondary cleft lip and palate deformities are proposed as a simple and reproducible method. These reproducible classification may be used to facilitate not only storing and analyzing of medical informations in computer but also the planning of secondary repairs

• 한국수학교육학회지시리즈A:수학교육
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• 제51권4호
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• pp.415-427
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• 2012

This study investigated the perception and utilization about computer of beginning secondary mathematics teachers by utilization frequency of computer. To increase utilization frequency of computer in school mathematics, our finding shows that beginning secondary mathematics teachers should have an interest in computer utilization and perceive computers as an important tool for mathematics learning. In addition, they are likely to use more frequently computer under the condition that computers have sufficient class materials and supplement their shortcomings that have derived less usage in math classes. Therefore, future studies have to investigate not only how to develope textbooks and run after-school classes but also how to make creative discretional activities by computer, which makes computers more useful for teacher training. In sum, the results of case studies for computer usability should be released to motivate computer utilization and increase mathematical thinking ability.

• 한국지리정보학회지
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• 제11권1호
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• pp.178-189
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• 2008

이 연구는 중등교육과정의 지리정보교육에서 경위도 좌표계에 대한 교육 강화의 필요성을 살펴본 것이다. 오늘날 GPS 기반의 위치정보 서비스는 경위도 좌표계의 활용을 크게 증가시키고 있다. 미국과 일본을 비롯한 선진국들은 이미 그들의 중등교육과정에 경위도 좌표와 관련된 내용을 명시하고 있으나 한국의 중등교육과정에서는 경위도 좌표에 대하여 구체적인 교육이 이루어지지 않고 있다. 경위도 좌표의 활용 현황을 알아보기 위해 주요 신문의 기사를 분석한 결과 2000년을 전후하여 경위도 좌표에 관한 내용이 포함된 기사가 꾸준히 증가하고 있음을 확인할 수 있었다. 그리고 상당수의 기사는 위치정보를 경위도 좌표 형식으로 제공하여 독자가 이를 활용할 수 있도록 하고 있다. 교육현장에서 경위도 좌표를 기반으로 공간정보를 활용하기 위한 하드웨어적 환경은 충분히 구축되어 있다. 세계화 시대를 살아갈 학생들이 공간정보를 올바르게 이해하고 활용할 수 있도록 하기 위해서 경위도 좌표계에 대한 구체적인 교육이 필요하다.