• Journal of KSNVE
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• v.3 no.2
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• pp.127-135
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• 1993

The structural control systems for civil engineering structures have got considerable attention in recent years, since they become effective protective systems. The key idea behind structural control is to keep the response of a structure within certain bounds dictated by serviceability, structural safety, and reliability. Recent activities in control algorithm development and control system design and practical aspects of their applications are sumarized, followed by a discussion on prossible future directions.

• YAKHAK HOEJI
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• v.37 no.2
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• pp.182-186
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• 1993

$\alpha$-Linolenic acid ethylester, $C_{19}$ spiroketalenolether polyyne, herniarin and steroid were isolated from the leaves of Artemisia selengensis (Compositae). The structures of the compounds were elucidated on the basis of spectroscopic evidence. Liver protective effects of these constituents were studied using galactosamine and CCI$_{4}$-induced cytotoxicity in primary cultured rat hepatocytes.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.710-715
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• 1995

Magnetic domains were observed using an image lock-in technique for backscattered electron contrast (Type II) with a 200 kV scanning electron microscope. Backscattered electrons indicate a difference in magnetic domain structures at the upper and lower parts of the upper pole in thin-film heads, changing the acceleration voltage. With this method, it is also possible to observe the domain structure of the thin-film head pole through a 10 to $20\;\mu\textrm{m}$ protective layer, and the upper shield of the MR head through the coil in the resist, alumina overcoat, and upper pole.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.641-646
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• 1998

The structures exposed to marine environment do not show long-term durability due to corrosion of steel and deterioration of concrete by the attack of various salts dissolved in sea water. In this study, Partial substitution of cement with fly ash(20%) or blast furnace slag(40%) was made together with the addition of 4 different corrosion-inhibitors, as a protective measure of concrete structures against chemical attack of salts. Combined effects of mineral and corrosion-inhibiting admixtures were tested by measuring the resistance and compressive strength of concretes under the simulated tidal condition, which consists of alternating 12 hour periods of immersion in artificial sea water and drying in air. Both the strength and concrete resistance were found to decrease in following order, regardless of the corrosion inhibitors the concretes with blast furnace slag, those with fly ash and those without any mineral admixtures. The interrelation between compressive strength of concrete and resistance was investigated.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1313-1317
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• 2006

In this study, various hydraulic phenomena were analyzed from the dam model experiments and the analyzed results were compared with existing computation results. Sungduk dam model structures were constructed using Froude similarity law by 1:50 scale. From the measurements of hydraulic phenomena at spillway channel, an improvement method was trying to be suggested over shortcoming of existing design plan. The result of model experiment showed no big difference with that of each part's numerical interpretation. Sidewall overflows were observed, as water conveyance occurred due to the linear characteristics of spillways, which raised the necessity for improving the linear forms of spillways. Also, it was judged to be necessary improving load pressure and establishing protective structures at the riverbed grounds of downstream channels.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.8
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• pp.50-55
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• 2012

Grounding is very important for electrical safety. But it is very difficult to secure enough space for the installation and management of grounding in the city because of the congestion of the buildings. Therefore, to solve this problem, this paper suggest structure-grounding application taking advantage of building structure as protective grounding. And, to verify its feasibility, this paper shows the result to measure and analyze grounding-resistance of structure for 12 buildings mainly structed in the city.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.821-824
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• 2004

For nuclear concrete structures on the coast, the prevention and management against salt damage is needed because they are being under the influence of the sea water at all times. In general, the deterioration of the concrete is generated in concrete surface firstly and then extended into concrete gradually as its service life increases. Therefore, the protective layer on the concrete surface is needed to establish and manage the durability of concrete. To enhance the durability performance of the existing and new concrete, the development and application of a high-performance penetration sealer is needed. The sealer has to have the functions that are able to prevent the attack of the moisture, carbon dioxide, and harmful substance from the outside. Therefore, the aim of this study is to development of a sealer for the long service-life and waterproof performance of a nuclear concrete structures.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.7 no.1
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• pp.53-76
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• 1979

During cosmetic treatments, SURFACTANTS penetrate into KERATINOUS TISSUES (hair, skin and nails). Whereas some of these surfactant molecules migrate to the vital tissues, a considerable fraction remains bound to the keratin. The extent of binding depends both on the nature of the head group and the length of the hydrophobic tail of the detergent molecules. In addition to entering the amorphous region of the keratin, some of the detergents also penetrate into the crystalline microfibrils and change their structures affecting their tensile properties. Owing to an uneven distribution of detergent molecules in the tissues, an anisotropy of the elastic moduli will occur, resulting in considerable internal stresses which, in rum, might lead to a deterioration of hair, skin and nails. The chemical behavior of keratins is also influenced by the presence of absorbed detergent in their structures. Depending on the detergents and the conditions, these effects can be either protective or detrimental. The deposition of detergent molecules into keratin can be enhanced or diminished by the inclusion of appropriate ingredients into the product formulae.

• Safety and Health at Work
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• v.13 no.4
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• pp.421-428
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• 2022

Background: The exposure to solar ultraviolet radiation is a significant risk factor generally underestimated by outdoor workers and employers. Several studies have pointed out that occupational solar exposure increased eye and skin diseases with a considerable impact on the lives and productivity of affected workers. The main purpose of this study was to evaluate the effectiveness against ultraviolet radiation of some measures recently undertaken for the protection of lifeguards in a coastal area of Tuscany. Methods: Different shading structures (gazebos and beach umbrella) were tested during a sunny summer's day on a sandy beach by means of two radiometers; the UV protection offered by some T-shirts used by lifeguards was also tested in the laboratory with a spectrophotometer. Results: The analysed shading structures strongly reduced the ultraviolet radiation by up to 90%, however a not always negligible diffuse radiation is also present in the shade, requiring further protective measures (T-shirt, sunglasses, sunscreen, etc.); the tested T-shirts showed a very good-excellent protection according to the Australian/New Zealand standard. Conclusion: Results obtained in this study suggest how the adoption and dissemination of good practices, including those tested, could be particularly effective as a primary prevention for lifeguards who are subjected to very high levels of radiation for long periods.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.806-809
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• 2003

Ion-induced secondary electron emission coefficient $({\gamma})$. of the patterned MgO thin film with geometrical structures has been measured by ${\gamma}$ - FIB(focused ion beam) system. The patterned MgO thin film with geometrical structures has been formed by the mask (mesh of ${\sim}$ $10{\mu}m^{2})$ under electron beam evaporation method. It is found that the higher ${\gamma}$. has been achieved by the patterned MgO thin film than the normal ones without patterning.