• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.261-264
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• 2003

Cold weather can lead to many problems in mixing, placing, setting time, and curing of concrete that can have harmful effects on its properties and service life. Korean Concrete Institute (KCI) defines cold weather as a period when the average daily air temperature is less $4^{\circ}C$ and recommends to cast concrete with special care such as shielding, heating and so on. The use of high early strength cements may improve the rate of hardening characteristics of concrete in cold weather by making it possible to achieve faster setting time and evolving more hydration heat than ordinary Portland cement. Higher early strength can be achieved using Type III cement especially during the first 7 days. The strength increase property of Type III cement at low temperature was studied. As a conclusion the heat or heat insulation curing period can be reduced to 50~75%. So, it can be used for cold weather concreting to reduce construction cost and extend the construction season.

• Journal of Forest and Environmental Science
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• v.31 no.2
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• pp.109-118
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• 2015

Allelopathy is an ecological phenomenon that refers to the beneficial or harmful effects of one plant on another plant, both crop and weed species, by the release of organic chemicals (allelochemicals) from plant parts by leaching, root exudation, volatilization, residue decomposition in soil and other processes in both natural and agricultural systems. Allelopathy can affect many aspects of plant ecology including occurrence, growth, plant succession, the structure of plant communities, survival, dominance, diversity, and plant productivity. In this review, we describe the concept of allelopathy, some mechanisms of operation within plants and then focus on a select number of gymnospermous tree genera: Ephedra, Pinus, Taxus, Cedrus, Juniperus, Picea, Cunninghamia and Araucaria. Pinus, Taxus (yew) and Cedrus (cedar) trees have a strong negative allelopathic effect on the germination, growth, or development of other plant species in the forest community.

• Electronics and Telecommunications Trends
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• v.35 no.4
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• pp.11-20
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• 2020

With the widespread use of high-performance electronics and mobile communications, electromagnetic interference (EMI) shielding has become crucial for protection against malfunctioning of electronic equipment and harmful effects to human health. In addition, smart sensor technologies will be rapidly developed in untact (non-contact) environments and personal healthcare fields. Herein, we introduce our recently developed technologies for flexible multifunctional EMI shielding, and highly sensitive wearable pressure-strain and humidity sensors realized using low-dimensional nanomaterials.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.720-725
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• 2000

To remove harmful gases from combustion exhaust gases. fundamental study on NOx removal using pulse corona discharge has been performed through experiments and simulations. The energy consumption should be decreased in order to apply non-thermal plasma technology to industry process. This work summarized the effects of $H_2O$ and Hydrocarbon additive in NOx removal efficiency. The Radical program is used to simulate high voltage discharge and the process of NOx removal. At last, experimental results were compared with simulation results to verify the reliability of this program.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.556-559
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• 1997

This paper describes the development process of mosquito trap with the effect of air cleaning by using the substance-field analysis and evolution pattern of systems in the theory of inventive problem solving (TRIZ). By the concept of standard solution about introducing S3 substance, modification of S1 (human) and S2 (mosquito) between first substance SI and second substance S2 with harmful effect, we got the concept of the mosquito trap with mosquito attractants instead of mosquito reluctants such as mosquito stick coil and skin medicine w~th bad and toxic smell. The number of mosquitos traped by one trap near cattle shed per one n~ght in summer, was over 10 thousands with some effects of air cleaning.

• Archives of Pharmacal Research
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• v.25 no.3
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• pp.349-356
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• 2002

The present study was performed to examine the effect of fangchinoline, a bis- benzylisoquinoline alkaloid, which exhibits the characteristics of a $Ca^{2+}$ channel blocker, on cyanide-induced neurotoxicity using cultured rat cerebellar granule neurons. NaCN produced a concentration-dependent reduction of cell viability, which was blocked by MK-801, an N-methyl-D-aspartate (NMDA) receptor antagonist, verapamil, L-type$Ca^{2+}$channel blocker, and L-NAME, a nitric oxide synthase inhibitor. Pretreatment with fangchinoline over a concentration range of 0.1 to 10 $\mu$M significantly decreased the NaCN-induced neuronal cell death, glutamate release into medium, and elevation of $[Ca^{2+}]_i$ and oxidants generation. These results suggest that fangchinoline may mitigate the harmful effects of cyanide-induced neuronal cell death by interfering with $[Ca^{2+}]_i$influx, due to its function as a $Ca^{2+}$ channel blocker, and then by inhibiting glutamate release and oxidants generation.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.511-516
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• 2007

Rubber wheeled AGT(Automated Guide-way Transit) system is a prominence transportation system for urban area, because of its low construction cost and management, low noise and vibration and fine exterior view. AGT system uses concrete tracks. Concrete can be easily damaged by the impact, change of temperature and external loads. The fault of concrete track is harmful not only to riding quality but also to bridge. Therefore, in this study, the effects of railway prominence to the bridge are surveyed by experimental method. The experiment was executed for PSC bridge at AGT test line in Kyungsan. And the test results for 5mm, 10mm prominence and without prominence are compared and investigated, according to the vehicle speed.

• Archives of Plastic Surgery
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• v.45 no.4
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• pp.298-303
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• 2018

Flap thinning is a procedure for making a thick flap thinner. This procedure does more than simply fill in the defected area, and it is better for reconstructing the area both functionally and aesthetically. However, because flap thinning is a rather blind procedure, it may have harmful effects on flap vascularity. Therefore, the vasculature of a flap must be understood before performing flap thinning. This paper analyzes the basic anatomy underlying flap thinning based on the previous anatomic study that categorized flaps into 6 types by their vascular structures. This paper also reviews specific studies of frequently practiced flap procedures (deep inferior epigastric artery perforator flap, thoracodorsal artery perforator flap, and anterolateral thigh flap) and presents important precautions for flap thinning procedures. Finally, this paper briefly examines the axiality of the subdermal plexus, which needs to be taken into account when performing flap thinning.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.4 s.181
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• pp.83-90
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• 2006

A robot manipulator is usually operated in two modes: free and constrained motion modes, depending on whether the robot is in contact with an environment or not. At the moment of contact, an impact occurs and can exert harmful effects to the robot or the object. In case of teleoperation, since a user may give an inadequately excessive velocity command to the slave due to insufficient visual information, the robot nay collide the object with an excessive speed and it possibly deteriorates the robot's performance causing vibrations and at worst, shortens its lifetime by its fracture. In this article, a new algorithm is proposed by introducing a command signal modification method on the basis of impedance control and validity of the proposed algorithm is demonstrated by performing simulations and experiments.

• Journal of the Korea Institute of Building Construction
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• v.4 no.3
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• pp.161-167
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• 2004

The sick house syndrome is occurred from the harmful elements that the building interior materials are given off after building construction or renovation. The appropriate methods, which is to prevent sick house syndrome from spreading have to be selected before building construction or renovation. Thus, this study is to measure the density of formaldehyde, one of the volatile organic compounds after sprinkling air-assisted-catalyst on the building interior space. As a result, the emit value of formaldehyde is measured 0.07ppm that is lower than the standard of Environmental Protection Agency and World Health Organization, 0.1ppm, and the standard of Ministry of Health, Labour, and Welfare of Japan, 0.08ppm.