• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.605-611
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• 2019

The fuel sloshing due to the rapid manoeuvre of the aircraft causes significant loads on internal components, which may break components or piping. In particular, a significant load is applied to the joint of the external fuel tank by sloshing movement, which may affect the safety of the aircraft when the joint of the external fuel tank is damaged. Therefore, in order to improve the survivability of aircraft and crew members, the design of external fuel tanks, and joints should be performed after evaluating the sloshing load through a numerical analysis of the fuel sloshing conditions. In this paper, a numerical analysis was performed on the sloshing test of the external fuel tank for rotorcraft. ALE (Arbitrary Lagrangian Eulerian) technique was used, and the test conditions specified in the U.S. Military Specification (MIL-DTL-27422D) was applied as the conditions for numerical analysis. As a result of the numerical analysis, the load on the joint of the external fuel tank was calculated. Moreover, the effects of sloshing movement on structural soundness were assessed through analysis of stress levels and margin of safety on metal fittings and composite containers.

• Journal of Conservation Science
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• v.33 no.6
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• pp.399-416
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• 2017

The 'Wat Phou and Associated Ancient Settlements within the Champasak Cultural Landscape' of Laos was designated as a UNESCO World Cultural Heritage in 2001. The uppermost structure of the Sanctuary in Wat Phou has been destroyed and being variably damaged, maintenance is required through scientific and systematic diagnosis. The Sanctuary of Wat Phou was constructed mainly using sandstones and bricks. There are physical damages including fracture, break out, exfoliation and interval as well as biological damages by lichen, mosses and weeds. According to the ultrasonic velocity measurement and property evaluation of the sandstones of the Sanctuary in Wat Phou, weathering index of the eastern side sandstones is 0.10 to 0.74 (mean 0.36), showing MW grade. Southern and northern side sandstones have relatively higher properties with average weathering indices of 0.30 and 0.32. The results of slope analysis of the Sanctuary, indicated that the 4th spot in the southern side has the largest slope of $5^{\circ}W$, seemingly due to the unstable ground around the Sanctuary. Based on the relative level measurement and past drawings, the Sanctuary is verified to have been located on ground with a certain slope rather than flatland. The ground of the southern side is inclined $1.51^{\circ}$ more than that of the northern side, which will affect the structural stability of the temple. The interval width of the selected southern spot is the largest with an average width of 159.5 mm, and the largest width is 328.3 mm at the top, since the width increases above rather than below, seemingly due to the unequal subsidence of the ground. Constant maintenance for conservation is required for the structural stability of the Sanctuary in Wat Phou, which was partly collapsed and has also suffered physical damage.

• Journal of Distribution Research
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• v.16 no.1
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• pp.1-27
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• 2011

I. Introduction: This study is to examine the structural relationships among exogenous variable (preliminary and post-support, franchisee's perceived business possibility, communication, moral hazard), the mediated variables(satisfaction, perceived risk, trust) and dependent variable(recontracting intention) in the food service franchise industry context. More specifically, this study has considered some realistic characteristics factors influencing satisfaction, perceived risk and trust between franchisors and franchisees and their further recontracting intention from the perspective of a practical approach. In this study, 437 data has been collected and used for the SPSS and AMOS analysis. The data were analyzed with structural equation modeling. Since the result of the overall model analysis demonstrated a good fit, we could further analyze our data. II. Research Model: This study is to examine the structural relationships among preliminary and post-support by franchisor, franchisee's perceived business possibility, and communication, moral hazard, has on effect on franchisee's satisfaction, perceived risk, trust and recontracting intention in the food service franchise industry context. Hypotheses are as following (Stern & EL-Ansary 1988; Oliver, 1997;Kee & Knox, 1970; Moorman, Deshpande & Zaltman, 1993; Perron, 1998; Zaheer, McEvily, Perrone, 1998). III. Result and Implication: We examined franchisee who have food service stores for samples of this study. The data were analyzed with structural equation modeling using path analysis. The result of the overall model analysis appeared as following: ${\chi}^2$ = 61.578 (d.f.=9, p<0.01), CFI =.990, GFI =.973, AGFI =.863, RMR =.019, RMSEA= .116, NFI = .988, TLI = .959. The findings can be summarized as follows: First, preliminary and post support of franchisor, perceived business possibility and communication positively influence to franchisee's satisfaction. Second, moral hazard of franchisor has negatively influence to franchisee's satisfaction and positively influence to perceived risk. Third, franchisee's satisfaction and trust has positively influence to recontracting intention. Fourth, franchisee's perceived risk has negatively influence to trust and recontracting intention. We can concluded that franchisor's preliminary and post support of franchisor, perceived business possibility and communication may be considered as the important factors influence to franchisee's satisfaction. Moral hazard has become a focused issue in franchise industry. Finally, the managerial implication has been stated as followings: First, in the process of building a systematic industry support franchise system and developing a creative business model, franchisee's stable profitability should be considered as the first important factor. The franchisee's trust to franchise may become a dominant factor that influence the business expansion of franchisor. Second, franchisor should communication with their franchisees and deal with the realistic difficulties faced by them with an effort. Third, the franchisor should achieve a synergy effect by utilizing the win-win strategy. The moral hazard strategy that achieving the profit through franchisee's damage will not be inadvisable to franchisor. Then the long-term oriented development and profitability can be maintained. To do so, the franchise industry may break away from the traditional business structure to improve management transparency and competitiveness on investment and organizational changing management. The conflict between franchisor and franchisee also can be reduced and big success can be achieved in the franchise industry.

• Applied Microscopy
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• v.36 no.1
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• pp.35-45
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• 2006

Plants of Vitex negundo are known to develop numerous trichomes throughout their body, where certain trichome types have been believed to be one of the plausible structures for the unique scents. In the current study. structural aspects of the trichomes have been examined in leaves and stems of Vitex negundo using TEM and SEM. Trichome types as well as structural changes that occurred in certain trichomes during secretion have been mainly focused. Three type of glandular trichomes and two types of non-glandular trichomes were developed in the epidermis of young and mature Vitex negundo plants. The glandular trichomes included the peltate type (Type 1), the capitate type (Type 2), and degraded capitate type (Type 3), whereas the non-glandular warty trichomes contained the multicellular (Types 4) and unicellular type (Type 5). Type 1 and 2 consisted of head and stalk cells, but their number and size were different. One secretory cavity was formed from the four head cells in the former, but only two head cells were involved in the latter. The cytoplasmic density in the head cell was quite high and in particular, sER and Golgi bodies were well developed. At initiation of their development, the cuticle layer of the head cells separated from the outer tangential wall to form a secretory cavity. Subsequently the cavity expanded acropetally and a large number of secretory vesicles continuously produced from the head cells until they filled the entire cavity. The cavity contained materials that would be soon discharged into intercellular spaces and/or into the air. The cavity began to decrease the volume by contracting at initial secretion but degrade rapidly within short time. It has been suggested that the mode of secretion in V. negundo is probably the eccrine secretion, since no break or rupture of the cavity has been observed during examination. Contrastingly Type 3 exhibited deterioration of the head cell at early stage. Type 4 was about $110{\sim}190{\mu}m$ long, consisting of $2{\sim}3$ cells, and distributed more in the adaxial epidermis compared to the abaxial surface. However, $20{\sim}30{\mu}m$ long Type 5 was extremely dense in both epidermis. Among several trichome types, Type 1 and 2 probably play an important role in discharging unique aromatic scents in plants of V. negundo.

• Journal of Science and Technology Studies
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• v.18 no.2
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• pp.95-133
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• 2018

Since the beginning of the millennium, 'Maker Movement' has been active throughout the world. Today, there is a maker fair every year in major cities of the world including Seoul, and the number of attendees is increasing day by day, so it can be seen as a kind of maker 'phenomenon'. The positive implication of the maker's movement is that it attempts to break down the monopoly of manufacturing and to restore the rights and capabilities of citizens as makers. Today, highly developed industrial capitalism has a tendency to structurally paralyse citizens, to tie their hands and feet, and to degenerate into consuming entities only. Therefore, it can be said that the maker movement has structural tensions in the relationship of neoliberal manufacturing culture. This study is an attempt to actively interpret the maker movement in terms of "critical making". The maker movement can trace its origins to "counterculture" and "new communalism" that emerged in the United States in the 1960s and 1970s. On the other hand, there is criticism that the maker movement can fall into another technology utopianism and function as an area of consumer society, and mobilize it in the direction of activating consumerism. Although the maker's movement is amorphous due to its characteristics and it is currently in progress, it is difficult to make crude definition yet. However, as the citizens who have been defined only as consumers of science and technology, are newly emerging as producers of makers, there have been great changes in the topography of science and technology and civil society. So the scientific implication of the maker movement is great in that it shows the possibility of causing it.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.679-688
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• 2000

Dispersants, which are used to break water-in-oil emulsions and to remediate oil-spills, are another water pollutants. In this study, magnetic separation technology was applied to remove dispersants from the sea. Magnetite and maghemite were used as magnetic sorbents and SDDBS, an anionic surfactant and Triton X-100, a nonionic surfactant, were employed as dispersants. Batch experiments were undertaken to study the sorption capacity and sorption equilibrium, and water-bath experiments were conducted to simulate the real situation and to describe the recovery of magnetic particles by the permanent magnet or electromagnet. Maghemite has rather constant removal efficiency for dispersants, regardless of surfactant species. On the other hand, removal efficiency by magnetite is higher for anionic surfactant than maghemite and is higher in distilled water than in seawater which contains more ions. The sorption of dispersants to magnetite is explained by electrostatic attraction and that of maghemite is described not only by electrostatic attraction, but also by structural characteristics that provide high sorption ability and surface condition. Water bath experimental results showed that recovery efficiency of magnetic particle after sorption for dispersants is nearly 100%. It is suggested that this magnetic separation technology is an effective way of dispersant removal because of short operating time, high sorption capacity, and high recovery efficiency of sorbents.

• Journal of Korea Port Economic Association
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• v.27 no.2
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• pp.355-372
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• 2011

Various incentive policies for transshipment cargo have been enforced without any evaluation of the effectiveness. Therefore, the purpose of this study is to evaluate the effect of volume incentive on container transshipment cargo. To be different from previous studies, this study tries to quantitatively assess the incentive effects by using econometric techniques. The result derived from the ARIMA type models indicates that the total amount of the increased transshipment cargo during the last 7 years is about one million TEU. In the meanwhile, the multivariate long run equilibrium model implies that the increased transshipment cargo is less than 0.5 million TEU for the 7 years. Furthermore, the structural break tests indicate that the volume incentive does not change the model structures. It means that the effect of volume incentive is not statistically significant. Consequently, the test results conclude the effect of volume incentive on transshipment cargo is not significant although the volume of transshipment cargo is increased to some extent by volume incentive. Considering the magnitude of BPA's expenditure, we doubt the effectiveness of volume incentive. This study, therefore, encourages the port authority to research a more efficient way to induce transshipment cargo rather than focusing on only volume incentives.

• Journal of the Korean Institute of Gas
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• v.7 no.2 s.19
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• pp.33-41
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• 2003

There exists high hazard when transporting LPG as well as using, storing, and producing. For small scale LPG consumer, retailers deliver LPG to customers via a truck loading many LPG cylinders. Suppose there occurred a accident during LPG cylinder transfer, this could result in serious damages to the life and properties in the near or neighbor of the accident spot. In this regard, we made a quantitative risk analysis to estimate the possible damages and the probability through the identification of accidents causes and the simulation of the possible scenario. In this study, we made the Excel & Visual Basic computer program to perform quantitative LPG accident analysis. The simulation showed the following results. In case of UVCE(Unconfined Vapor Cloud Explosion), the effect within l0m of the accident spot showed very severe structural damages and even the accident can break the window glasses of the area of 150 m apart from accident spot. In case of TNT corresponding probit analysis, after 10 minutes LPG leaking, $75\%$ window glasses of 40 m distance was expected to be broken. And $16\%$ frames of 20m distance, $10\%$ frames of 40m distance was expected to be collapsed.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.90-95
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• 2014

Nylon66 extrudates as a function of the extrusion number were prepared by a twin screw extruder. Chemical structures, thermal properties, melt index, crystal structures, mechanical properties such as the tensile strength, elongation at break and impact strength, and rheological property were measured by FT-IR, $^1H$-NMR, melt indexer, DSC, TGA, XRD, universal tensile tester, Izod impact tester, and rheometer. FT-IR and $^1H$-NMR characterizations indicated that the number of extrusions did not affect the chemical structure. The decrease in the molecular weight was checked by the melt index of extrudates. There were no effects of the thermal history on the melting and degradation temperature. The tensile and impact strength and modulus were found to be similar, regardless of the number of extrusions, but the elongation decreased significantly. The complex viscosity of extrudates at low frequencies decreased with the extrusion number. No structural changes after extrusion were confirmed from the fact that there was no change in the slope and shape of G'-G" plot.

• Journal of Korea Entertainment Industry Association
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• v.13 no.7
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• pp.15-23
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• 2019

This paper aims to identify the characteristics implied in the process of change of Stephen Sondheim's musical style and to derive the structural communication tools that connect the creator and audience and the implications. The strategies that appear in Sondheim's musical works are the following. First, Sondheim's early musical works follow the principles of book musical and emphasize the integration faithful to the basic elements such as the rhythm and meaning of the lyrics. Second, in the era of early postmodernism, Sondheim attempts the principle of extreme deconstruction through the concept musical Company and pursues rational thought through fragmented dramatic flow. Third, while maintaining dramatic linearity to overcome the lack of immersion caused by extreme deconstruction, Sondheim realizes a more elaborate and formalized fusion style of the principles of integration and deconstruction through the choruses and the songs of the characters in Little Night Music and Sweeney Todd. Finally, Sondheim attempts multiple experiments to break down the boundaries of act and scene and to express new subject matters through his works such as Sunday Park with George and Into the Woods. In conclusion, Sondheim's fusion experiments and strategies are the process of finding a framework and a medium of communication to induce dramatic immersion of audience and at the same time create rational thinking about social problems to deliver the message of the creative work with the leading aesthetics of the modern musical's box-office success.