• Biomedical Science Letters
• /
• v.12 no.4
• /
• pp.343-348
• /
• 2006

Drosophila Sog and vertebrate Noggin play important roles during development. They function as antagonists against BMP4 signaling and induce neural ectoderm during embryogenesis. They are also engaged in appendage formation by inhibiting BMP4 signaling during late development. To understand further functions of Sog, Supersog, which is a more potent form of Sog, and Noggin BMP4 antagonists during development, I performed the molecular genetic analysis using Drosophila embryogenesis and wing formation as assay systems. In cellular blastoderm embryos, Sog inhibited Dpp signaling, Drosophila BMP4 signaling, whereas Supersog or Noggin did not block Dpp signaling. During wing formation, Sog inhibited Sax type I receptor of Dpp signaling whereas Noggin inhibited Tkv type I receptor of Dpp signaling. However, Supersog inhibited both Sax and Tkv type I receptors. These results suggest that functions of BMP4 antagonists are developmental stage dependent and indicate that each BMP4 antagonist inhibits BMP4 signaling by blocking different BMP4 receptors.

• Journal of the Korean Society for Railway
• /
• v.8 no.6 s.31
• /
• pp.559-565
• /
• 2005

In this paper, we propose a stereoscopic video coding scheme for subway accident monitoring system. The proposed designed for providing flexible video among various displays, such ass control center, station employees and train driver. We uses MPEG-2 standard for coding the left-view sequence and IBMDC coding scheme predicts matching block by interpolating both motion and disparity predicted macroblocks. To provide efficient stereoscopic video service, we define both temporally and spatially scalable layers for each eye's-view by using the concept of Spatio-Temporal scalability. The experimental results show the efficiency of proposed coding scheme by comparison with already known methods and the advantages of disparity estimation in terms of scalability overhead. According to the experimental results, we expect the proposed functionalities will play a key role in establishing highly flexible stereoscopic video codec for ubiquitous display environment where devices and network connections are heterogeneous.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 1995.11a
• /
• pp.55-66
• /
• 1995

Earlier studies indicated clearly that information obtained from conventional statistics cannot provide guidance on detailed casualty analysis. Much more is needed if casualty statistics are to play a proficient and vigorous role in encouraging safety. Specific difficulties originate from making the causal relationships clear. Fault tree analysis and symbolic modeling of functional block diagram are an efficient aid in safety analysis so that these methods are generally used in other industries. This paper describes the application of these tools in shipping casualties and how to evaluate the relationships between different causes of ship casualties. Thesee methods are proved to be an efficient and useful tools to indicate the relationships between individual physical factors. In addition these models permit easy understanding and recognition of the factors leading to individual casualty

• Korean Journal of Breeding Science
• /
• v.40 no.2
• /
• pp.106-112
• /
• 2008

International conferences to block the spread of Avian bird flu occurred in Beijing, 2006 and others warned of the seriousness of the H5N1 strain. The meetings succeeded in generating billions of dollars from USA, EU and World Bank. Migratory birds seem to play a major role in the spread of the aggressive strain globally from Asia to Europe and Africa. Experiences of tolerance breeding of maize (Zea mays L.) for four decades against 20 biotic stresses suggest that the prime cause of the occurrence of H5N1 strain was due to the human beings' counter-efforts against nature. Excessive use of chemicals (spray and injection) in the commercial poultry farms had created high selection pressure on virus. The new strain had mutated for survival. Attempting to eliminate the virus by chemicals for 100% control is a dangerous way to control biotic stresses. This can create more aggressive strains. A solution would be to build up tolerability of the commercial animals against the virus. Improvement of poultry cage environments and respect for nature must be integrated. Potential foes must be watched.

• Journal of Institute of Convergence Technology
• /
• v.8 no.1
• /
• pp.15-20
• /
• 2018

Recently a GPU has acquired programmability to perform general purpose computation fast by running thousands of threads concurrently. This paper presents a parallel GPU computation algorithm for dense matrix-matrix addition and scalar multiplication using OpenGL compute shader. It can play a very important role as a fundamental building block for many high-performance computing applications. Experimental results on NVIDIA Quad 4000 show that the proposed algorithm runs 21 times faster than CPU algorithm and achieves performance of 16 GFLOPS in single precision for dense matrices with size 4,096. Such performance proves that our algorithm is practical for real applications.

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.188.2-188.2
• /
• 2003

Large-conductance $Ca^{2+}$ activated potassium channels $(BK_{ca})$ are widely distributed and play key roles in various cell functions. In nerve cells, B $K_{ca}$ channels shorten the duration of action potentials and block $Ca^{2+}$ entry thereby repolarizing excitable cells after excitation. $(BK_{ca})$ channel opening has been postulated to confer neuroprotection during stroke and has attracted attention as a means for therapeutic intervention in asthma, hypertension, convulsion, and traumatic brain injury. (omitted)

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2020.06a
• /
• pp.208-209
• /
• 2020

There is no disagreement that the construction sector will play an important role in inter-Korean economic development cooperation. However, very few studies have been made at North Korea's construction technology. North Korea shows a lot of differences from South Korea, from the quality standards of building materials to construction technology. It is clear that these differences will be a stumbling block to the promotion of construction projects in the inter-Korean cooperation stage. Therefore, the start of inter-Korean economic development cooperation should be preceded by work to clearly recognize each other's differences and lay the foundation for integration or compatibility. The purpose of this study is to compare the construction technology of rebar concrete construction. We compared the differences with Korea's construction method based on the construction books recently published in North Korea, and derived the characteristics of North and South Korea for each detailed process of reinforced concrete construction.

• International Journal of Computer Science & Network Security
• /
• v.24 no.5
• /
• pp.198-204
• /
• 2024

Correspondence security between IoT devices is a significant concern, and the blockchain makes the latest difference by reducing this matter. In the blockchain idea, the larger part or even all organization hubs check the legitimacy and precision of traded information before tolerating and recording them, regardless of whether this information is identified with monetary exchanges or estimations of a sensor or a confirmation message. In assessing the legitimacy of a traded information, hubs should agree to play out an uncommon activity. The chance to enter and record exchanges and problematic cooperation with the framework is fundamentally decreased. To share and access the executives of IoT devices data with disseminated demeanour, another confirmation convention dependent on block-chain is proposed, and it is guaranteed that this convention fulfils client protection saving and security. This paper highlights the recent approaches conducted by other researchers to secure the Internet of Things environments using blockchain. These approaches are studied and compared with each other to present their features and disadvantages.

• Journal of the Korean Academy of Esthetic Dentistry
• /
• v.22 no.1
• /
• pp.30-46
• /
• 2013

Porcelain fused to metal crown has been used mostly over the last 50 years for restorations in dentistry. However, the patients' awareness of aesthetic aspect, biocompatibility and the problems such as an allergy to metals led to the growing interest in the 'metal free restoration'. In particular, the price of the precious metals that have been mainly used to date has risen drastically, which made them impossible to play their role as oral restorative materials anymore, and in addition, the PFM restoration has intrinsic problems of chipping and fracture. Therefore, the CAD/CAM has been drawing more attention than ever due to the popular needs for the material that is more aesthetic and stronger for restoration of the molar implant. Considerations in carrying out the full zirconia restoration are as follows: 1) strength, 2) combination work, 3) light penetrability, 4) treatment of cracks, 5) the color reproducibility of the block, 6) the abrasivity of antagonistic tooth, 7) low temperature degradation. In this presentation, the color reproducibility of the block will be discussed. One of the biggest reasons for avoiding the full zirconia restoration is that it is difficult to reproduce the natural color compared to the conventional PFM restoration. Thus, many clinicians show reluctance due to the exposure of the ugly block when the coloring on the surface is removed after occlusal adjustment. From the experience of using blocks by Zirkonzahn for more than 4 years, it is considered that these problems can be addressed to some degrees. Accordingly, how to make restorations that are well in harmony with surrounding prosthesis or natural teeth will be discussed.

• Science of Emotion and Sensibility
• /
• v.3 no.2
• /
• pp.17-28
• /
• 2000

Psychoacoustic characteristics of automobile horns play significant role in resulting subjective evaluation and psychphysiological reactions. However, comparison and differentiation of physiological responses to commercially available horns is a complicated task due to the small contrast in technical features of horns and the influence of such processes as habituation on physiological outcome with the increased number of auditory stimulation trials. In a study on 10 college students, there was performed comparative analysis of reactivity of physiological responses mediated by central and autonomic nervous systems in order to identify the role of habituation on decrement of psychophysiological responsivity and assess the ability to differentiate subjectively most and least preferred, as well as most and least appropriate horns according to physiological manifestations. The EEG and autonomic responses to 7 automobile horns were analyzed during 3 blocks of trials, with varying order of stimuli and changed acoustic parameters of horns in each block. Thus, responses were analyzed for totally 21 trials of auditory stimulation. It was shown that electrodermal and cardiovascular responses have different reactivity patterns to repeated stimulation: skin conductance measures habituated, cardiac reactivity showed no signs of habituation, and the vascular response demonstrated sensitization. The temporal EEG exhibited marked habituation of fast beta band power, while alpha-blocking effect did not habituate during the course of experiment. Differentiation of physiological responses of most and least preferred and appropriate horns was possible in our study, however, some cardiovascular reactivity measures differentiated during the entire course of the experiment, while EEG and electrodermal parameters showed significant differences only during first block of trials, and were later affected by the habituation.