• 한국산업정보학회:학술대회논문집
• /
• 한국산업정보학회 1997년도 춘계학술대회 발표논문집
• /
• pp.163-181
• /
• 1997

This dissertation provides a theroetic study on the network security in general , the firewall in particular . In fact, the firewall has been recognized as a very promising option to obtain the security in the real world network environment . The dissertation provides a thorough theoretic investigation on the various problems raised in the computer network, and also explores a methodology of the security against IP spoofing. Moreover, it investigates a systematic procedure to make analysis plans of the firewall configuration. Based on the above investigation and analysis , this dissertation provides two approaches to network security, which address a number of issues both at the network and at application level. At the network level. a new methdo is proposed which uses packet filtering based on the analysis of the counter plot about the screen router. On the other hand at the application level, a novel method is exlored which employs security software , Firewall-1, on Bastion host. To demonstrate the feasibility and the effectiveness of the proposed methodologes, a prototype implementation is made. The experiment result shows that the screen router employing the proposesed anti-IP spoofing method at the network level is effective enough for the system to remain secure without being invaded by any illegarl packets entering from external hackers. Meanwhile , at the application level. the proposed software approach employing Firewall -1 is proved to be robust enough to provent hackings from the outer point to point protocol connection. Theoretically, it is not possible to provide complete secuirty to the network system, because the network security involove a number of issues raised from low level network equipments form high level network protocol. The result in this dissertation provides a very promising solution to network security due to its high efficiency of the implementation and superb protectiveness from a variety of hacking.

• Journal of Periodontal and Implant Science
• /
• 제36권2호
• /
• pp.531-554
• /
• 2006

Oral implants must fulfill certain criteria arising from special demands of function, which include biocompatibility, adequate mechanical strength, optimum soft and hard tissue integration, and transmission of functional forces to bone within physiological limits. And one of the critical elements influencing the long-term uncompromise functioning of oral implants is load distribution at the implant- bone interface, Factors that affect the load transfer at the bone-implant interface include the type of loading, material properties of the implant and prosthesis, implant geometry, surface structure, quality and quantity of the surrounding bone, and nature of the bone-implant interface. To understand the biomechanical behavior of dental implants, validation of stress and strain measurements is required. The finite element analysis (FEA) has been applied to the dental implant field to predict stress distribution patterns in the implant-bone interface by comparison of various implant designs. This method offers the advantage of solving complex structural problems by dividing them into smaller and simpler interrelated sections by using mathematical techniques. The purpose of this study was to evaluate the stresses induced around the implants in bone using FEA, A 3D FEA computer software (SOLIDWORKS 2004, DASSO SYSTEM, France) was used for the analysis of clinical simulations. Two types (external and internal) of implants of 4.1 mm diameter, 12.0 mm length were buried in 4 types of bone modeled. Vertical and oblique forces of lOON were applied on the center of the abutment, and the values of von Mises equivalent stress at the implant-bone interface were computed. The results showed that von Mises stresses at the marginal. bone were higher under oblique load than under vertical load, and the stresses were higher at the lingual marginal bone than at the buccal marginal bone under oblique load. Under vertical and oblique load, the stress in type I, II, III bone was found to be the highest at the marginal bone and the lowest at the bone around apical portions of implant. Higher stresses occurred at the top of the crestal region and lower stresses occurred near the tip of the implant with greater thickness of the cortical shell while high stresses surrounded the fixture apex for type N. The stresses in the crestal region were higher in Model 2 than in Model 1, the stresses near the tip of the implant were higher in Model 1 than Model 2, and Model 2 showed more effective stress distribution than Model.

• 한국전자통신학회논문지
• /
• 제19권1호
• /
• pp.65-76
• /
• 2024

최근 해상풍력산업이 활성화되면서 기존 화력 발전소 규모의 400MW 급 발전단지들이 개발되고 있다. 재생에너지는 에너지원에 따라 간헐성이 큰 특성이 있고, 최신 재생에너지 발전설비들은 제어기능을 갖는 인버터 기술로 구성되는 특징이 있다. 이러한 재생에너지원의 계통연계 확대에 따라 전력계통 접속을 위한 그리드코드도 점점 구체화되고 있고, 이에 따라 관련 검토도 활발히 진행되고 있다. 본 논문에서는 그리드 코드 준수를 위해 여러 해상풍력 발전단지들을 통합하여 공동접속설비로 접속하는 경우, 최적 무효전력 보상용량 선정 방법에 대해 제안한다. 그리드 코드의 요구조건을 기반으로, 전북 서남해 400MW 풍력발전단지의 무효전력 보상과 과도안정도를 분석한다. 이 분석은 PSS/E를 사용하여 각 터빈 배치안과 케이블 데이터로 발전단지 DB를 구축하고, 내·외부망 케이블의 충전전류에 의한 무효전력과 연계점에서 무효전력 보상용량을 산출한다. 또한 전력계통 DB에 연계해서 정적, 동적 안정도를 고찰한다.

• 대한수의학회지
• /
• 제38권4호
• /
• pp.720-729
• /
• 1998

Immunohistochemical technique of the c-fos primary gene protein, Fos, was used to analyze the effects of external factors on the neuronal activities in the periaqueductal gray(PAG) of the intact rats, sham-operated rats and post-operated stress control rats. In addition, the number of Fos positive neurons has been evaluated to verify the effects of cannula implantation and veratridine treatment on the neuronal activities in PAG area. The results were summerized as follow : 1. There was no significant difference in the number of Fos positive neurons observed in the caudal and middle portion of lateroventral PAG from cannula implanted rats and sham operated rats. 2. The number of Fos positive neurons in the PAG was not changed by the stress induced by connection of collecting tube to rats for 12 hours as compared to that of intact rats. 3. In the saline treated group, the Fos immunoreactivity in the PAG did not changed at 30 minutes and 1 hour after saline treatment as compared to that of intact rats. However, the number of Fos positive neurons was significantly increased at 2 hours after treatment compared to that of saline treated rats at 30 minutes after treatment. 4. The Fos immunoreactivity was dramatically increased at 30 minutes, 1 hour and 2 hours after veratridine treatment as compared to those of saline treated groups. The number of Fos immunoreative neurons showed the maximal level at 2 hours after veratridine treatment. 5. The Fos positive neurons induced by saline and veratridine treatment were mainly distributed in front of the microdialysis window. These results suggest that new microdialysis demonstrated in this study improves efficiency and accuracy to confine the neuronal activity in front of microdialysis window site. Moreover, this directional specificity allows us to locate probe tips adjacent to the brain area of the interest site rather than centering the probes within that brain area. Finally, This microdialysis method can be used to dialyse the neurotransmitters using concious and freely moving rats.

• 한국정보통신학회논문지
• /
• 제20권6호
• /
• pp.1177-1182
• /
• 2016

모니터링과 제어를 위한 대다수의 산업용 장비들은 항상 확장성 문제와 외부 프로토콜 호환성 문제가 발생하고 있다. 본 논문은 이기종 통신이 발생하는 산업용 통신을 위한 모니터링을 지원하기 위하여 프로토콜 변환이 가능한 보드를 개발하였다. 산업용 통신 모니터링 보드는 메인 보드와 서브 보드로 구성되며, 메인 보드들의 연결로 확장이 가능하다. 메인 보드는 AVR계열의 Atmega 2560을 사용하였고, 서브 보드는 Atmega 256, 128을 사용하였다. 메인보드에는 RS485 시리얼 슬롯 4개를 배치하여 서브 보드를 장착할 수 있게 설계하였다. 서브보드는 아날로그와 디지털 데이터 I/O를 지원하고, CAN과 Ethernet 통신을 이용한 모니터링이 가능하도록 개발하였다.

• 대한한의학원전학회지
• /
• 제33권1호
• /
• pp.89-101
• /
• 2020

Objectives : The purpose of this study is to research the Left-Renying and Right-Qikou pulse diagnosis. Methods : We set up locations of the Renying pulse(人迎脈) and the Qikou pulse(氣口脈) on left hand and right hand. On the basis of the medical texts and papers, we researched the relations between the Left-Renying and Right-Qikou pulse diagnosis and the etiological factors(病因), background of appearance of the Left-Renying and Right-Qikou pulse diagnosis, and practical use of medical practitioners of many generations to the Left-Renying and Right-Qikou pulse diagnosis. Results & Conclusions : The Left-Renying and Right-Qikou pulse diagnosis is a method to diagnosis the etiological factors, while it could also be assumed as a tool to apply herbal medicine. This assumption could be made based on the seventh volume of 『Maijing(脈經)』 of Wang Shuhe(王叔和). Chen Wuze(陳無擇) emphasized its function to distinguish etiological factors in 『Sanyinjiyibingzhengfanglun(三因極一病證方論)』, as did Li Dongyuan(李東垣) in 『Neiwaishangbianhuolun(內外傷辨惑論)』. Meanwhile, the connection between Left-Renying and Right-Qikou pulse diagnosis and Zangfu(臟腑) seems to have first been made in 『Maiyu(脈語)』 of Wu Kun(吳昆), while 『Zhenjiazhengyan(診家正眼)』 of Li Zhongzi(李中梓) shows traces of progress since the 『Maiyu』.

• 한국의상디자인학회지
• /
• 제3권2호
• /
• pp.51-62
• /
• 2001

This study was intended to investigate the contemporary meaning of transparent design expressed in contemporary fashion by inquiring into its plasticity expressed in contemporary design and fashion and analyzing the association between them. It used the comparative anesthetic method widely used by H. W lfflin and other scholars in eliciting the differences and similarities in styles. It attempted to investigate the plasticity of transparent design expressed in contemporary design by dividing it into the epidermal, spatial and ideological effects. Contemporary design expressed the epidermal effects such as lightness(nimbleness), smoothness, contrast and stress It expressed the spatial effects such as spatial flexibility through the interpenetration of interior and exterior spaces, expansion of the space and the like. And it expressed ideological effects such as openness, pureness, playfulness and the like. In terms of lightness, contemporary design expressed actual or visual lightness by using transparent materials. In terms of the interpenetration of interior and exterior spaces, it expressed the interpenetration of the interior space into the exterior spaces and vice versa. In terms of spatial expansion, contemporary design expressed the infinite spatial connection by drawing the exterior space into the interior space. Contrast and stress were formed by imposing visual unity on contemporary fashion by using opaque and transparent materials. In terms of openness, contemporary design expressed contemporary people's candor and dependability by making the inside of the building or object look outward. To express pureness, contemporary design used the clear and transparent image by using the glass or translucent materials taking on the pure property. To express playfulness, contemporary made use of the vagueness of the spatial boundary, the locational switching of inner and outer spaces, and interesting external forms occurring when light pass through opaque and transparent materials.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제5권2호
• /
• pp.89-101
• /
• 2005

Research on highly abstracted system modeling and simulation has received a great deal of attention as of the concept of platform based design is becoming ubiquitous. From a practical design point of view, such modeling and simulation must consider the following: (i) fast simulation speed and cycle accuracy, (ii) early availability for early stage software development, (iii) inter-operability with external tools for software development, and (iv) reusability of the models. Unfortunately, however, all of the previous works only partially addresses the requirements, due to the inherent conflicts among the requirements. The objective of this study is to develop a new system design methodology to effectively address the requirements mentioned above. We propose a new transaction-level system modeling methodology, called ViP (Virtual Platform). We propose a two-step approach in the ViP method. In phase 1, we create a ViP for early stage software development (before RTL freeze). The ViP created in this step provides high speed simulation, lower cycle accuracy with only minor modeling effort.(satisfying (ii)). In phase 2, we refine the ViP to increase the cycle accuracy for system performance analysis and software optimization (satisfying (i)). We also propose a systematic ViP modeling flow and unified interface scheme based on utilities developed for maximizing reusability and productivity (satisfying (ii) and (iv)) and finally, we demonstrate VChannel, a generic scheme to provide a connection between the ViP and the host-resident application software (satisfying (iii)). ViP had been applied to several System-on-a-chip (SoC) designs including mobile applications, enabling engineers to improve performance while reducing the software development time by 30% compared to traditional methods.

• 대한불안의학회지
• /
• 제11권2호
• /
• pp.136-142
• /
• 2015

Objective : Subjective tinnitus is defined as an acoustic sensation perceived without any external source. Patients with tinnitus have often experienced psychological distress and low quality of life. However, the connection between psychiatric characteristics and tinnitus has not yet been established. The purpose of this study was to investigate the relationship of psychiatric characteristics with tinnitus severity. Method : A total of 124 patients with tinnitus were included in the study. Demographic and clinical characteristics were retrospectively collected in the otolaryngology clinic. The self-reported scales including the Tinnitus Handicap Inventory, the Hospital Anxiety and Depression Scale and the Anxiety Sensitivity Index were used in this study. Results : The Pearson product moment correlation revealed significant correlations between tinnitus severity and psychiatric characteristics including depression (r=0.26, p<0.01), anxiety (r=0.38, p<0.01), anxiety sensitivity (r=0.27, p<0.01). After controlling for age, sex and awareness of tinnitus, tinnitus severity was positively correlated with anxiety (partial r=0.39, p<0.01) and anxiety sensitivity (partial r=0.28, p<0.01). These correlations remained significant in male but not in female patients. Conclusion : Results of the present study indicated that not only anxiety symptoms but also anxiety sensitivity could relate to tinnitus severity. Our findings have implications for the understanding of the psychiatric characteristics in patients with tinnitus.

• 조형예술학연구
• /
• 제8권
• /
• pp.211-239
• /
• 2005

The purpose of this thesis is to explore a common characteristic of the diverse oriental images mainly from the figurative point of view, and apply it to the contemporary expressions and methods of painting. To do that, I separated the concept of figure into two factors - form and image - and then approached and solved the problems of figure by explaining the two factors respectively. Separating form from image is neither to set two factors against each other nor to isolate any of those values. It is worth dividing the form and the image not only because the image of the oriental painting has a figurative value constituted from an external frame of the form, but also because it has a close connection with the meaning that the form holds inside. These are the reasons why I conceptualize the individual language of form and image. Furthermore, I attempted to investigate how those two factors and mutual relations between them make real figurative images under the principle of harmony and coexistence. The theme of this thesis - the figurative aesthetics and its contemporaneity in the oriental paintings is analyzed based on the understanding of 'figure' within the framework of oriental paintings. A research of image from the figurative point of view is valuable in that it criticizes the past method of thinking, and proposes an alternative formula for new way of thinking. In this regard, I indicated the limit of the theory of form-and-spirit that has been one of the most important conceptual theories . Instead, I' accessed to various aesthetic concepts - that are created in the course of image formulation - from the actual figurative point of view, and then even interpreted it as a figurative value of the oriental paintings and it's application within the specific and practical scope. During the course of research, I explored the conceptual elements of the tradition and the principle of figuration. I expect this study to make a footstone for bringing traditional aesthetics to the contemporary context of oriental painting.