• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.4
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• pp.24-29
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• 2011

When an emergency light turns on due to a blackout, the intensity of illumination is drastically changed from hundreds [1x] to 1.0[1x]. This sharp change of illumination intensity not only lowers the darkness adaptation of the eye, it also degrades the obstacle cognitive ability of the evacuees, resulting in secondary critical accidents due to anxiety, and fear. Thus, this study proposed a convertible emergency lighting fixture that controls the rate of speed of light in two stages by time with darkness adaptation of the eye in consideration. In addition, the effect of such emergency light is verified by suggesting an illumination simulation without increasing the number of light or capacity of battery to make it economically feasible.

• Animal Systematics, Evolution and Diversity
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• v.33 no.4
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• pp.256-261
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• 2017

Eucephalobus oxyuroides (de Man, 1876) Steiner, 1936 belonging to the family Cephalobidae Filpijev, 1934 (Cephalobomorpha) is newly reported from South Korea. This species is distinguished from other Eucephalobus species by its pointed tail terminus, high lips and relatively longer female tail and body. From many previous studies, intraspecific variation in this species has been reported for body length, absence/presence of probolae, and number/position of papillae in the posterior region of male, posing an obstacle for identification and phylogenetic analysis. In this study, details of the morphological characters and morphometric of E. oxyuroides Korean population are described and illustrated based on optical microscopy.

• Journal of the Korean Professional Engineers Association
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• v.42 no.5
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• pp.29-31
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• 2009

A general practice in software ordering behavior in public sector has been an enormous obstacle standing in development path of Korea's software industry. Standard on software development cost estimation is supposedly based on Function Point, but in general, it is on headcounting (a number of people involved in a project). Moreover, it is difficult to change a contract in an on-going project, since statement of work is not precisely and carefully described. But it has a simple solution. Design and Implementation should be a separate project, as in construction industry, and both power and responsibility for design should be given to an expert with a national-level qualification. Here, there is a simple way for Korea to reborn as one of the strongest software country.

• Journal of Mechanical Science and Technology
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• v.16 no.2
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• pp.137-146
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• 2002

In this paper, a path generation algorithm that uses sensor scannings is described. A scanning algorithm for recognizing the ambient environment of the Automatic Guided Vehicle (AGV) that uses the information from the sensor platform is proposed. An algorithm for computing the real path and obstacle length is developed by using a scanning method that controls rotating of the sensors on the platform. The AGV can recognize the given path by adopting this algorithm. As the AGV with two-wheel drive constitute a nonholonomic system, a linearized kinematic model is applied to the AGV motor control. An optimal controller is designed for tracking the reference path which is generated by recognizing the path pattern. Based on experimental results, the proposed algorithm that uses scanning with a sensor platform employing only a small number of sensors and a low cost controller for the AGV is shown to be adequate for path generation.

• Transactions of Materials Processing
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• v.6 no.3
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• pp.213-220
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• 1997

The microstructure of the inconel 690 alloy was varied by the solution treatment and the thermal treatment. The specimens having different microstructures were examined in order to understand the strengthening mechanism of the inconel 690. The level of supersaturation of carbon in the solid solution was increased by applying a longer solution treatment at 115$0^{\circ}C$. As increased carbon content in the solid solution, more carbides precipitated during the thermal treatment at $700^{\circ}C$. Since the carbides played a role of obstacle on the movement of dislocations, a higher tensile strength was obtained in the sample having a large number of carbider. The accumulation of dislocations at the grain boundary carbides caused the development of intergranular fracture which led to a lower elongation.

• The Korean Journal of Zoology
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• v.37 no.2
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• pp.255-261
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• 1994

Recombinant human pBrathyriod hormone related peptide (1-341 (rhPTHrP) has been known to stimulate bone resorption in intact bone tissue culture system. Osteoclast has been known as a primary responsible cell for bone resorption. To examine the effect of rhPTHrP on this cell, we employed disaggregated rat osteodast culture. As a result, we found that rhPTHrP sisnificBntly elevates both the number and total area of resorbed pits in this culture. On the other hand, the conflicting results between disagsregated rat osteoc13st culture and Ca2+-deficient hen osteoclast culture system have been a big obstacle for the progress of bone research. To verify the differences between rat 3nd chick osteoclast system, we performed the same experiment using chick embryonic osteoclast. Since the similar results were obtained from the disaggregated chick osteoclast culture, the discrepancy between chick and rat osteoclast culture study seemed to be due to the difference in culture method, rather due to the species-difference.

• Journal of Ginseng Research
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• v.16 no.2
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• pp.138-145
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• 1992

Rooting test of 5 species plants in Acanthopanax genus was carried out to see the comparative effect of growth regulators NAA IBA and IAA. And the results are summarized as in the following compendia; (1) When hard and soft-wood cutting from new shoot of 5 species were taken and dipping treated with growth regulators such as NAA IBA and IAA at varied concentration levels their roofings were mostly more superior to the control that untreated. And also treatment of NAA and IBA among treated substances were more effective than IAA. (2) The effects on the rooting number and rate made a great difference according to species of Acanthopanax genus even if the same regulator was treated. (3) Decreasing effects of rooting by high concentration obstacle (especially at 2,000 rpm) of NAA and IBA in other species except A. sieboldianum were mostly serious. On the other hand, that in case of IAA treatment was not risen in most species except A. sessiliflorus.

• Journal of Integrative Natural Science
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• v.5 no.2
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• pp.72-78
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• 2012

Multidrug resistance is a major obstacle in cancer chemotherapy. Cancer cells efflux chemotherapeutic drug out of cell by means of transporter and reduce the active concentration of it inside cell. Such transporters are member of the ATP binding cassettes (ABC) protein. It includes P-gp, multiple resistant protein (MRP), and breast cancer resistant protein (BCRP). These proteins are widely distributed in the human cells such as kidney, lung, endothelial cells of blood brain barrier etc. However, there are number of drugs developed for it, but most of them are getting transported by it. So, still there is necessity of a good modulator, which could effectively combat the transport of chemotherapeutic agents. Natural products origin modulators were found to be effective against transporter such as flavonoids, which belongs to third generation modulators. They have advantage over synthetic inhibitor in the sense that they have simple structure and abundant in nature. This review focuses on the P-gp structure its architecture, efflux mechanism, herbal inhibitors and their mechanism of action.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.314-317
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• 2000

Cluster system provides attractive scalability in terms of computation power and memory size. With the advances in high speed computer network technology, cluster systems are becoming increasingly competitive compared to expensive parallel machines. In parallel processing program, each task load is difficult to predict before running the program and each task is interdependent each other in many ways. Load imbalancing induces an obstacle to system performance. Most of researches in load balancing were concerned with distributed system but researches in cluster system are few. In cluster system, the dynamic load balancing algorithm which evaluates each processor's load in runtime is purpose that the load of each node are evenly distributed. But, if communication cost or node complexity becomes high, it is not effective method for all nodes to attend load balancing process. In that circumstances, it is good to reduce the number of node which attend to load balancing process. We have modeled cluster systems and proposed marginal dynamic load balancing algorithms suitable for that circumstances.

• Journal of information and communication convergence engineering
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• v.11 no.4
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• pp.282-287
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• 2013

A real-time digital holographic display is the core technology for the next-generation 3DTV. Holographic display requires a considerably large amount of calculation. If generating a large number of digital holograms is intended, the amount of calculation and the time required increase exponentially. This is a significant obstacle in a real-time hologram service. This paper proposes an algorithm that increases the speed of generating a Fresnel hologram by using a recursive addition operation covering the entire coordinate array of a digital hologram. The 3D object designed to calculate the digital hologram uses a depth-map image produced by computer graphics. The proposed algorithm is a technique that performs the computer-generated holography (CGH) operation with only recursive addition of all of the hologram's coordinates by analyzing the regularity between the 3D object and the digital hologram coordinates. The experimental results show that the proposed algorithm increases the operation speed by 70% over the technique using the conventional CGH equation and by more than 30% over the previously proposed recursive technique.