• 수면정신생리
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• 제10권2호
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• pp.88-92
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• 2003

Sleep-disordered breathing (SDB), including snoring, sleep apnea and upper airway resistance syndrome are common problems in children. The pathophysiological mechanism of SDB in children is unclear but may include hypoxemia and changes in sleep architecture. Children with SDB show reduced neurocognitive function, and memory and attentional capacity. Furthermore, these children show increased problematic behaviour and reduced school performance. Whether early recognition and treatment of SDB in children may improve neurocognitive function and school performance remains to be fully evaluated in the future.

• 혜화의학회지
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• 제20권1호
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• pp.69-83
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• 2011

Objectives: This study aimed to investigate the effects of Amyda sinensis (AS) on allergic inflammation mechanism related atopy dermatitis. Methods: To investigate the effects of AS, We study inhibitory effect of AS on the levels of pro-inflammatory cytokines released from Raw264.7 cell stimulated with LPS (lipopolysaccaride), and EoL-1, THP-1, Jutkat cell stimulated with DP (Dermatophagoides pteronyssinus), and LPS indused acute inflammatory BALB/c mouse model. Result: AS reduced the levels of IL-$1{\beta}$ released from Raw264.7 cell stimulated with LPS at 20 ug/ml, 5 ug/ml concentration, and reduced the levels of IL-6 in a dose-dependent. AS significantly reduced the levels of MCP-1 released from EoL-1 cell stimulated with DP (Dermatophagoides pteronyssinus) at all the concentration, and significantly reduced the level of IL-8 at 0.1 ug/ml concentration. AS significantly reduced the levels of MCP-1 released from THP-1 cell stimulated with DP (Dermatophagoides pteronyssinus) at 1 ug/ml concentration, and reduced the level of IL-6 in a dose-dependent. AS significantly reduced the levels of IL-4 released from Jutkat cell stimulated with DP at all the concentration, and significantly reduced the level of IL-5 at 0.1 ug/ml. 1 ug/ml concentration,. and reduced the level of TNF-${\alpha}$ in a dose-dependent. AS significantly reduced the levels of TNF-${\alpha}$, IL-6, IL-$1{\beta}$, in LPS indused acute inflammatory BALB/c mouse model, in a dose-dependent. Conclusion: These result suggested that AS has suppressive effect on pro-inflammatory cytokines in various cell lines through the regulation of immune system. AS could be applied on the medicinal sources for treatment of immune abnormal diseases such as atopy dermatitis afterward.

• 한국인터넷방송통신학회논문지
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• 제16권1호
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• pp.193-198
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• 2016

안전한 플랜트 설비의 상태 감시 및 장애 진단을 위해 무선 센서를 이용한 플랜트 설비용 모니터링 시스템이 연구되고 있다. 플랜트 설비에서는 저전력 뿐만 아니라 안전사고와 직결된 긴급 상황시 실시간성도 고려해야 한다. 본 논문에서는 플랜트 시설에서 지연시간 감소를 위한 동적 듀티사이클 조절 기법을 제안한다. 제안된 동적 듀티사이클 조절 기법은 센싱된 데이터 값의 긴급한 정도에 따라 미리 정의된 위험 그룹으로 구분하여 적응적으로 듀티사이클 주기를 조절한다. 실시간성을 평가하기 위해 고정 듀티사이클 기법과 동적 듀티사이클의 예상 지연시간을 확률적으로 분석하였다. 비교 결과, 플랜트 시설과 같이 이상 징후 발생 시 에너지를 소모하더라도 실시간성을 제공해야 하는 상황에서 제안 동적 듀티사이클 기법이 더 효과적임을 확인하였다.

• 대한전자공학회논문지TC
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• 제42권7호
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• pp.19-26
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• 2005

최근 무선 인터넷의 수요가 기하급수적으로 증가함에 따라 Mobile IPv6가 제안되었으며, 이에 따른 핸드오버 지연을 줄이기 위한 빠른 핸드오버 기법이 제안되었다(IETF). 본 논문에서는 빠른 핸드오버 기법에서 발생하는 패킷의 손실 문제와 패킷의 비순서 문제를 해결하고 이로 인한 처리 지연을 줄일 수 있는 버퍼링 기법을 제안하였다. 또한 제안된 다양한 버퍼링 구조에 의한 빠른 핸드오버 기법의 성능 영향을 시뮬레이션을 통하여 분석하였다. 시뮬레이션을 통한 분석 결과, 제안된 버퍼링 기법은 패킷의 손실과 패킷의 비 순서를 해결하였고, 또한 기존 빠른 핸드오버 방식보다 버퍼링 기법은 최대 27$\%$정도 지연을 감소하였다.

• Korean Journal of Acupuncture
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• 제33권3호
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• pp.95-101
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• 2016

Objectives : This study aims to overview the therapeutic mechanism of back-shu points in terms of sympathetic visceral motor nervous system. Methods : Studies about autonomic nervous system, and studies and ancient texts about back-shu points were reviewed. We interpreted possible mechanism of back-shu points considering similarities of anatomical and physiological characteristics of back-shu points and visceral motor nervous system. Results : Afferent signals for organ lesions that can develop the symptoms of autonomic neurological symptoms, pain, hyperalgesia through the skin segment. Through a physical examination of the myotome and dermatome, it is possible to diagnose segmental disorders. Treatment stimulation of the thick fibers of the disorder segment skin can reduce abnormal autonomic influence over the sympathetic reflex mechanism. In addition, if spinal muscles are relaxed, the pressure on the nerve roots could be reduced and consequently the hyperactivity of the sympathetic visceral motor signal would be suppressed. Conclusions : The back-shu points treatments work through the mechanism of the sympathetic nervous reflex. Moreover, segmental acupuncture can reduce tension of the spinal muscles, thereby improving pathological conditions of the sympathetic nervous system.

• 대한기계학회논문집
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• 제18권12호
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• pp.3109-3117
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• 1994

To operate a flexible mechanism in high speed its weight must be reduced as far as the structural strength does not decrease too much, but a light-weighted mechanism causes undesirable elastodynamic responses deteriorating the system performance. Besides, clearance within the connections of mechanisms causes rapid wear, increased noise and vibration. Even if the problems described above must be considered in the initial design stage, there has been no effective design process which takes account of the correlation between dynamic characteristics of flexible mechanism and the clearance effect at the joint. In this study, the generalized elastodynamic governing equations which include dynamic characteristics and boundary conditions of flexible mechanism are derived by variational calculus and solved by using FFM theory. To take the clearance effect at joint into account a new dynamic model is presented and also the method of modified stiffness/damping matrix is proposed to activate the dynamic clearance model, which cooperates with the developed governing equation very easily. As the results of this study, the proposed method(modified stiffness/damping matrix) to calculate clearance effect was proved to be superior to the existing one(force reaction method) in solution convergency and calculation performance. Besides this method can be easily adopted to the complex shape joint without calculation of reaction force direction.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1051-1054
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• 2003

For micro-weighing, null balance method is widely used in the precision industrial fields, such as biomedicine, semiconductor, chemistry and so on. In order to obtain high resolution and large measurement range simultaneously, the mechanism should be analyzed and optimized. However, large measurement error can be generated according to the mass loading position and this error is called as a corner loading error. The corner loading error is caused by the parallelism error of a Roberval mechanism used to minimize it. The corner loading error is one of the most dominant error sources that should be removed. It is possible to design that the mechanism has no corner loading error theoretically, but the mechanism of the micro weighing device is very difficult to be realized as original design due to assembling and manufacturing error. For the required specification of the device, the precise manufacturing technique under a few $\mu\textrm{m}$ is required for the realization of the design. In this paper, the effects of the parallelism error are analyzed by using Lagrange method and verified by experiment. Also, the compensation mechanism is proposed and the corner loading error is reduced by restoring tile parallelism.

• 한국통신학회논문지
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• 제27권7C호
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• pp.696-703
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• 2002

전통적인 지능망 부하제어에서 개별적인 SCP(Service Control Point) 보호가 주요 관점이었다면, 본 논문에서는 지능망 전체 네트워크 자원 활용의 최적화를 통한 부하제어를 주요 관점으로 하였다. 이는 이동 에이전트 기술의 이용으로 가능해 지는데 이동 에이전트는 실행환경이 구현된 모든 시스템으로의 이동이 가능하고 독자적으로 작업 수행이 가능한 소프트웨어이다. 본 논문에서는 이동 에이전트를 이용한 과부하 제어 메커니즘과 이동절차를 제안하였다. 제안한 이동 에이전트를 이용한 과부하 제어 메커니즘은 이동 에이전트를 이용해 서비스 특성에 따른 지능망 과부하를 제어할 수 있고 이동 절차는 지능망 부하 변화에 따른 이동 에이전트의 이동 방법이다. 시뮬레이션결과 제안한 메커니즘은 기존 Call Gapping메커니즘보다 SCP 부하율과 시도 호 실패 수에서 우수한 성능을 보였으며 SCP과부하 시 SS NO.7 네트워크 트래픽의 감소를 가져왔다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권10호
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• pp.2862-2882
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• 2023

With the development of networking technology, it has become common to use various types of network services to replace physical ones. Among all such services, electronic voting is one example that tends to be popularized in many countries. However, due to certain concerns regarding information security, traditional paper voting mechanisms are still widely adopted in large-scale elections. This study utilizes blockchain technology to design a novel electronic voting mechanism. Relying on the transparency, decentralization, and verifiability of the blockchain, it becomes possible to remove the reliance on trusted third parties and also to enhance the level of trust of voters in the mechanism. Besides, the mechanism of blind signature with its complexity as difficult as solving an elliptic curve discrete logarithmic problem is adopted to strengthen the features related to the security of electronic voting. Last but not least, the mechanism of self-certification is incorporated to substitute the centralized certificate authority. Therefore, the voters can generate the public/private keys by themselves to mitigate the possible risks of impersonation by the certificate authority (i.e., a trusted third party). The BAN logic analysis and the investigation for several key security features are conducted to verify that such a design is sufficiently secure. Since it is expected to raise the level of trust of voters in electronic voting, extra costs for re-verifying the results due to distrust will therefore be reduced.

• 한국지반공학회논문집
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• 제21권3호
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• pp.65-77
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• 2005

본 연구에서는 계단식 보강토 옹벽에 대한 측소 모형실험 수행하고 그 결과를 토대로 계단식 보강토 옹벽의 파괴 메카니즘을 분석하였다. 보강토 옹벽의 모형설험은 5m 높이의 현장옹벽에 대해 상사법칙을 적용하여 축소$\cdot$모사하였으며 상사법칙 적용 결과에 따라 보강재를 선택하여 실험을 실시하였다. 또한, 파괴 메카니즘 분석을 위해 자중에 의한 파괴를 성공적으로 유도하였다. 실험결과를 토대로 보강토 옹벽의 상$\cdot$하단 옹벽의 이격거리와 보강재 길이가 파괴 양상에 미치는 영향을 분석하였으며 아울러 현재 적용되고 있는 설계기준의 타당성 검토하였다.