• Journal of the Architectural Institute of Korea Planning & Design
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• v.33 no.12
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• pp.73-83
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• 2017

Due to the changes in the contemporary society, small-scale traditional markets have declined and lost their functions as the center of neighborhood commercial and cultural affairs. While most traditional markets are deteriorating, there exist rare cases of neighborhood small-scale traditional markets that continuously maintain their vitality and popularity. This paper examines urban spatial characteristics of those markets. As for the cases, this paper inventoried eighteen such markets in Gwanak-gu, Seoul. The research methods include literature reviews, on-site investigation of total 18 such markets, and participant observations. The findings of this paper are as follows: There are distinctive differences in the urban-spatial characteristics of physical environmental factors between the revitalized markets and declining markets. In terms of neighborhood and commercial environment, the franchised super-markets are not necessarily in competition with small-scale traditional markets. The former often has symbiotic relationship the latter, if the small scale traditional markets are strategically located in between residential areas and subway stations, providing active pedestrian networks. There are many outdoor display stands in the revitalized markets, while the declining markets rarely have them. The market improvement projects such as transforming the open space into arcade space, hardly have effects on revitalization of the small-scale traditional markets.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.4
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• pp.915-922
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• 2017

Demand Response Market (DR Market) has risen as one of the key solutions to address the growth and fluctuation of electricity consumptions. In Korea, DR market has been in operation since 2014, where the focus has been mainly on large-scale loads. Small-scale DR market, however, is becoming increasingly important because small power consumers' contribution to the national power consumption has been increasing and because small loads tend to show large fluctuations. Furthermore, small-scale DR can improve social awareness on energy issues which can bring additional impacts. In this paper, we provide the findings from a small-scale consumer DR pilot. The pilot was conducted in the summer of 2016 on over 5,000 small-scale users in Korea, and smartphone applications were used in the pilot. The effectiveness of small-scale DR Market is analyzed and addressed, and the results indicate a promising future of small-scale DR Market.

• The Journal of Fisheries Business Administration
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• v.40 no.1
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• pp.1-26
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• 2009

The aquaculture management considers the maintenance of households lifehood more than profit maximization. As aquaculture industry has developed enterprise farms appeared, and the small and the large scale farms coexist. The features of coexistence could be summarized as followings. First of all, the large scale farms show the higher net profit while the small scale farms show the higher profit per 1ha and the earning rate. Secondly, in the case of over 2ha, the earning rate is stable in spite of the scale expansion. Moreover, in processing method, dried seaweed occupy the biggest proportion in the small scale farms while the raw seaweed occupy the biggest proportion in the large scale farms. Lastly, the scale of farms becomes larger, the participation rate of household labor rises. This thesis analyses the efficiency of Korean seaweed farms in the way of DEA model and suggests the improvements for the efficiency management. The mean technical, pure technical and scale efficiencies were measured to be 0.88, 0.96 and 0.91, respectively. Among the 20 farms included in the analysis, 10 were technically efficient and 12 were scale efficient. In conclusion, it is shown that the aquaculture farms has been becoming the form of coexistence. This appearance results in the effort for reducing the cost in the small scale farms and in profit maximization in the large scale farms. On the other hand, middle scale farms is inefficient compared with the small or large scale farms. Therefore, in order to achieve the efficiency, it is necessary to accomplish economy of scale by extending farm size or to cut expenses by reducing farm area. In other word, the efforts for achieving the efficiency is required in a different direction in spite of the same scale.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.155-158
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• 1996

Magnetic fields correlated on several kiloparsec scales are seen in spiral galaxies. Their origin could be due to the winding up of a primordial cosmological field or due to amplification of a small seed field by a turbulent galactic dynamo. Both options have difficulties: There is no known battery mechanism for producing the required primordial field. Equally the turbulent dynamo may self destruct before being able to produce the large scale field, due to excess generation of small scale power. The current status of these difficulties is discussed. The resolution could depend on the nature of the saturated field produced by the small scale dynamo. We argue that the small scale fields do not fill most of the volume of the fluid and instead concentrate into intermittent ropes, with their peak value of order equipartition fields, and radii much smaller than their lengths. In this case these fields neither drain significant energy from the turbulence nor convert eddy motion of the turbulence on the outer scale to wave like motion. This preserves the diffusive effects needed for the large scale dynamo operation.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.6
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• pp.49-57
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• 2003

Although there are several experimental techniques to evaluate the seismic behavior and performance of civil structures, small-scale models in mast of physical tests, instead of prototypes or large-scale models, would be used due to a limitation on capacities of testing equipments. However, the inelastic seismic response prediction of small-scale models has some discrepancies inherently because the similitude law is generally derived in the elastic range. Thus, a special attention is required to regard the seismic behavior of small-scale models as one of prototypes. In this paper, differences between prototypes and small-scale models pseudodynamically tested on steel column specimens are investigated and an alternative to minimize them is suggested. In general, small-scale models could have the distorted stiffness induced from some experimental errors on test setup, steel fabrication and so on. Therefore, a modified similitude law considering both a scale factor for length and a stiffness ratio of small-scale model to prototype is proposed. Using the modified similitude law to compensate experimental errors, the pseudodynamic test results from modified small-scale model are much improved as compared with the results of prototype. According to the pseudodynamic test results of small-scale steel models, it can be concluded that the modified similitude law proposed could be effective in simulating the seismic response of prototype structures.

• Journal of Wetlands Research
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• v.18 no.3
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• pp.267-274
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• 2016

Sewerage supply in rural community is the important for water quality protection of water system such as river, lake and wetland. And characteristic of small scale wastewater system that have wide range of inflow and concentration in sewage should be considered for stable operation of small scale wastewater treatment plant. In this research, characteristics of flow ratio (flow / designed flow), effect on treatment efficiency of small scale wastewater treatment plant and assessment of optimal flow ratio were conducted through analysis on operation result of 18 small scale wastewater treatment plant in Bong-hwa gun. As a result, flow ratio shows the higher value during summer. However pollutants concentration in sewage was shown the higher concentration during autumn and winter. Treatment of small scale wastewater treatment plant is increased when flow ratio increased, and nutrient treatment efficiency is more sensitive to change of flow ratio than organic compound and suspended solids. According to this research result, it need to be maintained flow ratio 0.8 over value for stable treatment efficiency of small scale wastewater treatment plant.

• Smart Structures and Systems
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• v.21 no.3
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• pp.279-286
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• 2018

The free longitudinal vibration of a circular truncated nanocone is investigated based on the nonlocal elasticity theory. Exact analytical formulations for tapered nanostructures are derived and the nonlinear differential governing equation of motion is developed. The nonlocal small scale effect unavailable in classical continuum theory is addressed to reveal the long-range interaction of atoms implicated in nonlocal constitutive relation. Unlike most previous studies applying the truncation method to the infinite higher-order differential equation, this paper aims to consider all higher-order terms to show the overall nonlocality. The explicit solution of nonlocal stress for longitudinal deformation is determined and it is an infinite series incorporating the classical stress derived in classical mechanics of materials and the infinite higher-order derivative of longitudinal displacement. Subsequently, the first three modes natural frequencies are calculated numerically and the significant effects of nonlocal small scale and vertex angle on natural frequencies are examined. The coupling phenomenon of natural frequency is observed and it is induced by the combined effects of nonlocal small scale and vertex angle. The critical value of nonlocal small scale is defined, and after that a new proposal for determining the range of nonlocal small scale is put forward since the principle of choosing the nonlocal small scale is still unclear at present. Additionally, two different types of nonlocal effects, namely the nonlocal stiffness weakening and strengthening, reversed phenomena existing in nanostructures are observed and verified. Hence the opposite nonlocal effects are resolved again clearly. The nano-engineers dealing with a circular truncated nanocone-based sensors and oscillators may benefit from the present work.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.10
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• pp.217-223
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• 2019

The purpose of this study was to measure the indoor air quality of small-scale apartments and then proposed a method to improve the indoor air quality of the small-scale apartments by comparing with the result of indoor air quality in the Clean-Healthy House. In case of formaldehyde, a highly volatile organic compound, the concentrations of indoor measured both in small-scale apartments and the Clean Healthy houses did not exceed- the guideline of Korea. The guideline of Korea for acetaldehyde was not available, so the guidelines of Japan and the World Health Organization were used to measure the concentration of acetaldehyde. The study results demonstrated that three out of seven small-scale apartments investigated exceeded the guideline of Japan; and the preliminary research on the Clean-Health Houses was low at about 30-60% of the guideline of Japan. The result of the VOCs measurement showed that toluene, ethylbenzene, and styrene in some small-scale apartments exceeded the guideline of Korea. However, the Clean-Healthy Houses in the previous studies did not exceed the guideline of Korea with regard to all the pollutants. Therefore, this study suggests the application of the construction standards of the Clean-Healthy house in order to improve the indoor air quality of small-scale apartments. In addition, the current study anticipates that improvement of the indoor air quality in the residential environments should be universally applied, not limited to the type and size of the residence.

• International Journal of Railway
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• v.4 no.2
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• pp.50-55
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• 2011

The dynamic stability of railway vehicle has long been one of the important issues in railway safety. The dynamic simulator has been used as a tool for investigating the dynamic stability of railway vehicles and wheel/rail interfaces. In particular, small scale simulators have been widely used in laboratory studies instead of full scale roller rigs which can be quite costly and rather inconvenient for testing out the effect of diverse design parameters. But techniques for design of a small scale simulator for the fundamental study about the dynamic characteristics of the wheel-rail systems and the bogie systems have not been well developed in Korea. Therefore, a research on the development of a small scale simulator for investigating bogie dynamics needs to be undertaken. The present paper investigates design of a small-scaled derailment simulator and the design of a small scale bogie. The simulator developed can be used to investigate the effect of diverse parameters such as attack angle, wheelbase and cant on dynamic behavior of the bogie and key dynamic performance parameters such as derailment coefficient and critical speed.

• Journal of the Korean Chemical Society
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• v.49 no.2
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• pp.208-214
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• 2005