• 융합보안논문지
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• 제21권2호
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• pp.29-35
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• 2021

UART(Universal asynchronous receiver/transmitter)는 데이터를 직렬 형태로 전환하여 전송하는 하드웨어 장치로서 대부분의 임베디드 시스템에서 시스템 진단 및 디버깅 용도로 널리 사용되고 있다. 해커는 UART의 기능을 이용하여 시스템 메모리나 펌웨어에 접근할 수 있고 시스템의 관리자 권한 취득을 통한 시스템 장악도 가능하다. 본 논문에서는 UART를 통해 침투하는 해커의 공격을 방어하기 위한 보안 UART를 연구하였다. 제안한 기법은 약속된 UART 통신 프로토콜을 사용하는 인가된 사용자만이 UART 접속을 허용하고 비인가자의 접속은 불허한다. 또한, 스니핑을 통한 프로토콜 분석을 막기 위해 데이터를 암호화하여 전송한다. 제안한 보안 UART 기법을 임베디드 리눅스 시스템에 구현하고 성능검증을 수행하였다.

• 정보보호학회논문지
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• 제14권5호
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• pp.3-10
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• 2004

무선 랜은 액세스 포인트를 경유하여 인터넷을 사용할 수 있기 때문에 접근 제어의 중요성을 가지고 있다. 또한 무선 랜을 이용하기 위해서는 EAP의 인증과정을 거치게 된다. 이러한 액세스 포인트 접근과 인증 과정에 대한 치명적인 공격 중의 하나가 DoS(Denial of Service) 공격이다. 즉 악의적인 공격자가 액세스 포인트의 접근을 막거나 또는 인증 과정에서 서버의 메모리 및 중앙처리장치의 계산 능력 등을 강제적으로 소비시킴으로써 합법적인 사용자가 서비스를 받지 못하게 한다. 본 논문에서는 무선 랜에 대한 DoS 공격을 접근 제어, 자원의 할당, 인증프로토콜 상에서의 공격으로 나누어 각 공격에 대한 방어법을 제시하였다. 액세스 포인트 접근에 대한 문제는 사전 검증 단계 및 보안 수준 변수에 의해, 자원의 할당에 대한 공격은 부분적인 stateless 프로토콜에 의해, 프로토콜상의 약점은 타임스템프와 접근 제한 변수에 의해 개선하였다.

• 한국농촌건축학회논문집
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• 제24권3호
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• pp.1-11
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• 2022

Purpose: This place, which is currently becoming an issue due to historical preservation and landscape protection, is also a place where urban residents around Taereung actually visit often. Thus, this study aims to analyze the importance of the evaluating factors in creating a relatable image of the city. Methods: Evaluation items were selected by reviewing related books and research literatures and reassessing the reviewed items through an expert group interview (FGI). For the selected evaluation items, the relative importance of the evaluation items for the place image was analyzed by applying the hierarchical analysis technique (AHP) to each user group. Result: A place becomes a memory in people's experiences and time, and it has the image and identity of the region where those experiences and memories are found again as a space called "place". The method of analyzing the importance of evaluation items between place images used in this study quantified the factors recognized as abstract images and identified the degree of influence between elements, but has limitation in that it targeted specific places. However, the analysis method on the place image recognition suggests the use of itemized variables for characteristics between place images, so future research on the identity of other place images can be conducted together. Also, the evaluation method of the image that recognizes the place has an objective meaning in that it can measure the image of the place quantitatively. In the future, it can be applied in creating an image forming factor or urban identity for place recognition in many regions

• 사물인터넷융복합논문지
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• 제8권1호
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• pp.79-85
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• 2022

사물인터넷(IoT)은 다양한 플랫폼, 컴퓨팅 성능, 기능을 가지는 장치를 연결한다. 네트워크의 다양성과 IoT 장치의 편재로 인해 보안 및 개인 정보 보호에 대한 요구가 증가하고 있다. 따라서 암호화 메커니즘은 이러한 증가된 요구 사항을 충족할 만큼 충분히 강력해야 하고 동시에 저 사양의 장치에 구현될 수 있을 만큼 충분히 효과적이어야 한다. 논문에서는 IoT에서 사용할 수 있는 다양한 유형의 장치에 대한 최신 암호화 기본 요소 및 체계의 성능 및 메모리 제한 사항을 제시한다. 또한, IoT 네트워크에 자주 사용되는 저 사양의 장치에서 가장 일반적으로 사용되는 암호화 알고리즘의 성능에 대한 자세한 성능 평가를 수행한다. 데이터 보호 기능을 제공하기 위해 바이너리 링에서 암호화 비대칭 완전 동형 암호화와 대칭 암호화 AES 128비트를 사용했다. 실험 결과 IoT 장치는 대칭 암호를 구현하는데 충분한 성능을 가지고 있었으나 비대칭 암호 구현에서는 성능이 저하되는 것을 알 수 있다.

• 정보보호학회논문지
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• 제32권5호
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• pp.845-853
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• 2022

스마트폰의 메모리 용량이 증가하면서 스마트폰에 저장된 개인 정보의 종류와 양도 증가하고 있다. 하지만 최근 악의적인 공격자의 악성 앱이나 수리기사 등의 타인으로 인해 스마트폰의 사진, 동영상 등의 다양한 개인 정보가 유출될 가능성이 증가하고 있기 때문에, 사용자의 이러한 개인 정보를 보호할 수 있는 다양한 정보 은닉 앱이 출시되고 있다. 본 논문은 이러한 정보 은닉 앱의 암호 알고리즘 및 데이터 보호 기능을 분석하여 안전성 및 취약점을 분석 및 연구했다. 이를 위해 우리는 Google Play에 등록된 정보 은닉 앱 중에서 전 세계적으로 가장 많이 다운로드된 AppLock 3.3.2 버전(December 30, 2020)과, 5.3.7 버전(June 13, 2022)을 분석했다. 접근 제어 기능의 경우, 사용자가 입력한 패턴을 암호화하기 위한 값들이 소스 코드에 평문으로 하드코딩 되어있으며 암호 알고리즘이 적용된 패턴 값은 xml 파일에 저장한다는 취약점이 존재했다. 또한 금고 기능의 경우 금고에 저장하기 위한 파일과 로그 파일을 암호화하지 않는 취약점이 존재했다.

• Structural Engineering and Mechanics
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• 제91권1호
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• pp.39-47
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• 2024

Bridge deterioration shows the change of bridge condition during its operation, and predicting bridge deterioration is important for implementing predictive protection and planning future maintenance. However, in practical application, the raw inspection data of bridges are not continuous, which has a greater impact on the accuracy of the prediction results. Therefore, two kinds of bridge deterioration models are established in this paper: one is based on the traditional regression theory, combined with the distribution fitting theory to preprocess the data, which solves the problem of irregular distribution and incomplete quantity of raw data. Secondly, based on the theory of Long Short-Term Memory (LSTM) Recurrent Neural Network (RNN), the network is trained using the raw inspection data, which can realize the prediction of the future deterioration of bridges through the historical data. And the inspection data of 60 prestressed concrete box girder bridges in Xiamen, China are used as an example for validation and comparative analysis, and the results show that both deterioration models can predict the deterioration of prestressed concrete box girder bridges. The regression model shows that the bridge deteriorates gradually, while the LSTM-RNN model shows that the bridge keeps great condition during the first 5 years and degrades rapidly from 5 years to 15 years. Based on the current inspection database, the LSTM-RNN model performs better than the regression model because it has smaller prediction error. With the continuous improvement of the database, the results of this study can be extended to other bridge types or other degradation factors can be introduced to improve the accuracy and usefulness of the deterioration model.

• 생물정신의학
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• 제12권1호
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• pp.42-61
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• 2005

Objectives:The ginsenoside Rg1 and Rb1, the major components of ginseng saponin, have neurotrophic and neuroprotective effects including promotion of neuronal survival and proliferation, facilitation of learning and memory, and protection from ischemic injury and apoptosis. In this study, to investigate the molecular basis of the effects of ginsenoside on neuron, we analyzed gene expression profiling of SH-SY5Y human neuroblastoma cells treated with ginsenoside Rg1 or Rb1. Methods:SH-SY5Y cells were cultured and treated in triplicate with ginsenoside Rg1 or Rb1($80{\mu}M$, $40{\mu}M$, $20{\mu}M$). The proliferation rates of SH-SY5Y cells were determined by MTT assay and microscopic examination. We used a high density cDNA microarray chip that contained 8K human genes to analyze the gene expression profiles in SH-SY5Y cells. We analyzed using the Significance Analysis of Microarray(SAM) method for identifying genes on a microarray with statistically significant changes in expression. Results:Treatment of SH-SY5Y cells with $80{\mu}M$ ginsenoside Rg1 or Rb1 for 36h showed maximal proliferation compared with other concentrations or control. The results of the microarray experiment yielded 96 genes were upregulated(${\geq}$3 fold) in Rg1 treated cells and 40 genes were up-regulated(${\geq}$2 fold) in Rb1 treated cells. Treatment with ginsenoside Rg1 for 36h induced the expression of some genes associated with protein biosynthesis, regulation of transcription or translation, cell proliferation and growth, neurogenesis and differentiation, regulation of cell cycle, energy transport and others. Genes associated with neurogenesis and neuronal differentiation such as SCG10 and MLP increased in ginsenoside Rg1 treated cells, but such changes did not occur in Rb1-group. Conclusion:Our data provide novel insights into the gene mechanisms involved in possible role for ginsenoside Rg1 or Rb1 in mediating neuronal proliferation or cell viability, which can elicit distinct patterns of gene expression in neuronal cell line. Ginsenoside Rg1 have more broad and strong effects than ginsenoside Rb1 in gene expression and related cellular physiology. In addition, we suggest that SCG10 gene, which is known to be expressed in neuronal differentiation during development and neuronal regeneration during adulthood, may have a role in enhancement of activity dependent synaptic plasticity or cytoskeletal regulation following treatment of ginsenoside Rg1. Further, ginsenoside Rg1 may have a possible role in regeneration of injured neuron, promotion of memory, and prevention from aging or neuronal degeneration.

• 대한간호학회지
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• 제23권4호
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• pp.664-677
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• 1993

The purpose of this study was to provide basic data for the development of educational material in Korean for patient3 being discharge after open heart surgery. The subjects were 45 adult patients who were seen in the out -patient department of the thoracic surgery unit of P University hospital between February 1993 and May 1993. The data were collected through a chart review and interview. Nursing needs, and the patients status related to diet, activity, medication, physical and psychoemotional limitations were analyzed. The results are summarized as follows ; 1. Mitral valve replacement was the most frequent type of surgery(91.2%). In most cases, a mechanical valve was used (91.0%) . The duration of admission after the operation was two to four weeks for most of the patients(48.9%). The follow-up period was between one and two years for 28.9% of the patients and below 6 years for all of the patients. 2. Many Patients didn’t know the importance of a low salt diet(57.8%), and did not get any education on low salt diet (66.7%). Gimchi was included as one of the most commonly ingested foods (77.8%). All of the patients indicated nursing needs related to education about low salt diets and further they indicated a major interest in foods that are harmful (57.7%) or foods that are safe(51.1% ). 3. Most patients did not recognize the need for limitations on physical activity(84.4%). Further, 31.1％ of them could not return to work at the time of the study. All patients had nursing needs related to physical activity, with the most frequent questions being about the permissble degree of activity and special cautions dictated by their illness (60.0%). 4. Many patients were ignorant of the necessity of medication(55.6%) . Forty percent of the patients were taking additional drugs, usually herb drugs. The time and duration of medication and the side effects of drugs were common concerns (57.7%) related to nursing. needs about medication and were mentioned by all of the patients. 5. All of the patients complained of physical discomfort including the following : memory disturbance(62.2%), weight gain(60.0%), chest tightness (55.6%), hair loss(51.1%), sleep disturbance(46.7%) and other symptoms in that order of frequency. Nursing needs related to physical condition were a concern for all of them. The viability and function of the replaced valve(53.3%) and weight gain(60.0%) were mal or concerns. 6. Looking at their psychoemotional condition it was found that 36 patients(80.0%) were emotionally unstable. The causes were physical discomfort(17 patients), insufficient knowlege of open heart surgery(6 patients), fear of death(6 patients), familial over protection(2 patients ) and lack of support (5 patients).

• 한국조경학회지
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• 제36권2호
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• pp.14-23
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• 2008

한강은 대한민국 수도 서울을 가로지르는 거대한 스케일의 매력적인 강이다. 그러나 근대화 과정에서 일괄적 인 호안공사로 직강화 되어 본연의 자연스러움과 하천의 건강성을 점차 상실하였다. 이를 극복하고 한강 중심의 개혁을 통해 수변도시 서울의 이미지를 확고히 하여 고급 브랜드화 하겠다는 한강르네상스 계획이 진행 중이다. 본 연구는 한강르네상스 사업의 일환으로 진행된 여의도 한강공원 국제 설계경기 공모 당선작의 설계전략과 내용을 서술하고자 한다. 계획의 주안점은 기본적으로 여의도 한강공원이라는 새로운 워터프런트의 정체성을 대변하는 3가지 이슈를 가지고 접근하였다. 첫째, 여의도는 비록 개발에 의해 인공적인 섬으로 변했지만 한강에서 과거의 기억을 가지는 유일한 공간이다. 모래섬의 서정성과 물가의 감성적인 기억을 가지는 장소로 계획하고자 하였다. 둘째, 한강르네상스 프로젝트의 6가지 지구 중 서로 마주 보고 있는 용산과 여의도는 중심지 역으로서 국제적인 금융, 업무지 역으로 조성된다. 용산의 철저히 도시적인 모습에 반해, 목가적 풍경과 고층건물이 절묘하게 어우러지는 색다른 풍경의 여의도 워터프런트를 제안하여 용산과의 적극적인 상호관계를 형성하고자 하였다. 마지막으로, 본 계획안에서는 현상공모 범위 밖인 여 의도공원과 본 현상공모 대상인 여의도 한강공원 관계를 재설정해 보고자 하는 것이었다.

• Smart Structures and Systems
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• 제4권2호
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• pp.221-232
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• 2008

This paper represents the final results of a research program sponsored by the European Commission through project WIND-CHIME ($\underline{W}$ide Range Non-$\underline{IN}$trusive $\underline{D}$evices toward $\underline{C}$onservation of $\underline{HI}$storical Monuments in the $\underline{ME}$diterranean Area), in which the possibility of using advanced seismic protection technologies to preserve historical monuments in the Mediterranean area is investigated. In the current research, the dynamic characteristics of two outstanding Mamluk-Style minarets, which similar minarets were reported to experience extensive damage during Dahshur 1992 earthquake, are investigated. The first minaret is the Qusun minaret (1337 A.D, 736 Hijri Date (H.D)) located in El-Suyuti cemetery on the southern side of the Salah El-Din citadel. The minaret is currently separated from the surrounding building and is directly resting on the ground (no vaults underneath). The total height of the minaret is 40.28 meters with a base rectangular shaft of about 5.42 ${\times}$ 5.20 m. The second minaret is the southern minaret of Al-Sultaniya (1340 A.D, 739 H.D). It is located about 30.0 meters from Qusun minaret, and it is now standing alone but it seems that it used to be attached to a huge unidentified structure. The style of the minaret and its size attribute it to the first half of the fourteenth century. The minaret total height is 36.69 meters and has a 4.48 ${\times}$ 4.48 m rectangular base. Field investigations were conducted to obtain: (a) geometrical description of the minarets, (b) material properties of the minarets' stones, and (c) soil conditions at the minarets' location. Ambient vibration tests were performed to determine the modal parameters of the minarets such as natural frequencies and mode shapes. A $1/16^{th}$ scale model of Qusun minaret was constructed at Cairo University Concrete Research Laboratory and tested under free vibration with and without SMA wire dampers. The contribution of SMA wire dampers to the structural damping coefficient was evaluated under different vertical loads and vibration amplitudes. Experimental results were used along with the field investigation data to develop a realistic 3-D finite element model that can be used for seismic risk evaluation of the minarets. Examining the updated finite element models under different seismic excitations indicated the vulnerability of such structures to earthquakes with medium to high a/v ratio. The use of SMA wire dampers was found feasible for reducing the seismic risk for this type of structures.