• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.6
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• pp.77-87
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• 2007

It will need a quite long time to replace IPv4 protocol, which currently used, with IPv6 protocol completely, thus we will use both IPv4 and IPv6 together in the Internet during the period. For coexisting protocols, IETF standardized various IPv4/IPv6 transition mechanisms. However, new security problems of IPsec adaptation and IPv6 packet filtering can be raised by tunneling mechanism which mainly used in transition mechanisms. To resolve these problems, we suggested two improved schemes for packet filtering functions, which consists of an inner header filtering scheme and a dedicated filtering scheme for IPv4/IPv6 transition mechanisms. Also we implemented our proposed schemes based on Linux Netfilter framework, and we tested their filtering functions and evaluated experimental performance of our implementation on IPv4/IPv6 transition testbed. These evaluation tests indicated that our improved packet filtering functions can solve packet filtering problems of IPv4/IPv6 transition mechanisms without severely affecting system performance.

• The Korean Journal of Pain
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• v.37 no.2
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• pp.91-106
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• 2024

The mechanisms of the chronic pain and depression comorbidity have gained significant attention in recent years. The complement system, widely involved in central nervous system diseases and mediating non-specific immune mechanisms in the body, remains incompletely understood in its involvement in the comorbidity mechanisms of chronic pain and depression. This review aims to consolidate the findings from recent studies on the complement system in chronic pain and depression, proposing that it may serve as a promising shared therapeutic target for both conditions. Complement proteins C1q, C3, C5, as well as their cleavage products C3a and C5a, along with the associated receptors C3aR, CR3, and C5aR, are believed to have significant implications in the comorbid mechanism. The primary potential mechanisms encompass the involvement of the complement cascade C1q/C3-CR3 in the activation of microglia and synaptic pruning in the amygdala and hippocampus, the role of complement cascade C3/C3a-C3aR in the interaction between astrocytes and microglia, leading to synaptic pruning, and the C3a-C3aR axis and C5a-C5aR axis to trigger inflammation within the central nervous system. We focus on studies on the role of the complement system in the comorbid mechanisms of chronic pain and depression.

• Molecules and Cells
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• v.26 no.2
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• pp.107-112
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• 2008

Invasion mechanisms of pathogens and counteracting defense mechanisms of plants are highly diverse and perpetually evolving. While most classical studies of plant defense have focused only on defense-specific factor-mediated responses, recent work is beginning to shed light on the involvement of non-stress signal components, especially growth and developmental processes. This shift in focus links plant resistance more closely with growth and development. In this review, we summarize our current understanding of how pathogens manipulate host developmental processes and, conversely, of how plants deploy their developmental processes for self-protection. We conclude by introducing our recent work on UNI, a novel R protein in Arabidopsis which mediates cross-talk between developmental processes and defense responses.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.4 s.107
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• pp.25-32
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• 2004

Flocculation of fibers and its distribution in paper are related to flocculation mechanisms, retention and drainage. Relationship between flocculation mechanisms and physical properties of paper has not been fully studied. In this study, flocculation of fibers was investigated by changing microparticles for flocculation mechanism analysis. When fillers were not added, formation and strength were deteriorated by 100, 300, or 500 ppm of linear PAM (all L-PAM), All L-PAM + 1200 ppm inorganic microparticle (1200-IM), all L-PAM + 120 ppm organic microparticle (120-OM), all L-PAM + 1200 ppm organic microparticle (1200-OM) because of too much flocculation. When 5, 15, $25\%$ (od.w/w) fillers were added, retention and drainage process were not affected by the extent flocculation when 500 ppm L - PAM, 500 ppm L - PAM + 1200- IM, and 500 ppm L - PAM + 120 ppm OM were added.

• Journal of Agricultural Extension & Community Development
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• v.5 no.1
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• pp.11-30
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• 1998

The lack of close working relationship between agricultural research, extension organizations and farmers, is one of the most difficult problems confronting agricultural technology system. Systems approach is an effective method to use in indentifying lingkage problems in agricultural technology system, and it is a problem-solving methodology. There are two basic types of linkage mechanisms; organizational and managerial. Organizational mechanisms involve the structural modification of the research and extension organizations involved in an agricultural technology system. The other major type of lingkage mechanisms involves a range of managerial interventions such as joint planning and review activities, collaborative program activities, and resource allocation procedures, etc.

• Tribology and Lubricants
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• v.6 no.1
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• pp.108-115
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• 1990

Wear diagrams, which are the three dimensional representations of the dependence of the wear rate on the applied pressure and the sliding speed, were constructed with the pin on ring type wear test results using 52100 wear couples. The pressure and speed ranges from 0.45 MPa to 45.30 MPa and from 0.012 m/sec to 0.12 (0.120)m/sec, respectively. The results show the mild to severe transition, which suggests the change of the wear mechanisms as a function of the pressure and sliding speed. The SEM micrographs of the corresponding worn area shows clearly that different wear mechanisms dominate.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.2
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• pp.290-301
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• 2014

The first purpose of this review is to outline some of the background information necessary to understand the mechanisms of action of fibre-degrading enzymes in non-ruminants. Secondly, the well-known and understood mechanisms are described, i) eliminating the nutrient encapsulating effect of the cell wall and ii) ameliorating viscosity problems associated with certain Non Starch Polysaccharides, particularly arabinoxylans and ${\beta}$-glucans. A third, indirect mechanism is then discussed: the activity of such enzymes in producing prebiotic oligosaccharides and promoting beneficial cecal fermentation. The literature contains a wealth of information on various non starch polysaccharide degrading enzyme (NSPase) preparations and this review aims to conclude by discussing this body of work, with reference to the above mechanisms. It is suggested that the way in which multi- versus single-component products are compared is often flawed and that some continuity should be employed in methods and terminology.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.12
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• pp.1041-1047
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• 2002

It is known that parallel-type mechanisms have many singularities than serial-type mechanisms. In haptic application, these singularities deteriorate the system performance when the haptic system displays the reflecting force. Moreover, different from general manipulators, haptic systems can't avoid the singular point because they are operated by user's random motion command. Although many singularity-free algorithms for serial mechanisms have been proposed and studied. singularity-free algorithms for parallel haptic application have not been deeply discussed. In this paper, various singularity-free algorithms, which are appropriate to parallel haptic system, will be discussedand evaluated.

• International Journal of High-Rise Buildings
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• v.5 no.1
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• pp.51-62
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• 2016

The concept of introducing viscous damping devices between outriggers and perimeter columns in tall buildings to provide supplementary damping and improve performance, reduce structural costs, and increase available usable area was developed and implemented by Smith and Willford (2007). It was recognized that the relative vertical movement that would occur between the ends of outriggers and columns, if they were not connected, could be used to generate damping. The movements, and correspondingly damping, can potentially be significantly increased by amplifying them using simple "mechanisms". The mechanisms also make it possible to increase the number of available dampers and thus further increase supplementary damping. The feasibility of mechanisms to amplify supplementary damping and enhance structural performance of tall, slender buildings is studied with particular focus on its efficacy in improving structural performance in wind loads.

• Earthquakes and Structures
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• v.10 no.2
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• pp.351-366
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• 2016

The structural collapse of masonry structure under dynamic loading displays many possible failure mechanisms often related to interaction between structural components. Roof collapse is one of the major damage mechanisms observed in masonry structures during an earthquake. Better connection between the roof diaphragm and walls may be preventing roof collapse, but it can affect other failure mechanisms. In spite of this fact, less attention has been paid to the influence of the roof diaphragm effect on masonry structures and little research has been implemented in this field. In the present study, the roof diaphragm effect on the unreinforced masonry structure under dynamic loading has been experimentally investigated. Three one-quarter scale one-story adobe masonry house models with different roof conditions have been tested by subjecting them to sinusoid loading on a shaking table simulator. Phenomena such as failure pattern, dynamic performance of masonry structure were examined.