• The Journal of the Acoustical Society of Korea
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• v.24 no.6
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• pp.303-308
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• 2005

In this paper, the acoustic properties of the light bulb are presented based on a new light bulb source system of continuously transmitting implosive signal . We describe the results of analysis of bulb signals and comparison with Previous works. The results show that Peak-source-level and Primary resonant frequency are increasing with increasing source depth. This bulb source can be used for the purpose of geoacoustic parameter inversion and source tracking in sha]low water via matched field processing.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.4
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• pp.334-341
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• 2014

Due to the rise of international oil prices, with the continued increase of vessel operating costs, profitability has gradually deteriorated in the some case of South Korea ferry shipping. Therefore, it is necessary to improve the resistance performance of passenger ship. Goose neck bulb can be one of the methods to improve the resistance performance of passenger ship. Goose neck bulb has been applied to passenger ships operated in Europe and large cruise line. But there is no application example in the passenger ship to be operated on a regular basis in the sea near Korea. It is needed to provide reference data that can be applied efficiently goose neck bulb on the medium-sized passenger ships. This study, intended for the medium-sized passenger ship operated short international routes, presents the design of the hull form that goose neck bulb has been applied. And the resistance performance of the designed hull confirmed by numerical simulation. The numerical simulation is performed while changing the local shape of the goose neck depending on the bulb parameters. This study finds bulb parameters and their range that can affect the resistance performance. Thus, it is possible to provide a foundation to develop the optimal design technique and regression analysis on the resistance performance and goose neck bulb.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.27 no.1
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• pp.75-82
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• 1991

The present paper describes a preliminary design method by using the computer graphics for creation of the fore and after body profiles of fishing vessel. It is well known that the Form Parameter design method has some merits at an early stage of design, and the B-spline curve generation technique has some prior properties in representing hull form with the computer graphic. The B-spline curve generation technique combined with the form parameter design method is employed to generate the profiles of fishing vessel. For fore body the stem profiles with bulbous bulb or without one are considered. And for after body the stern profiles of cruiser type and the transom type are generated with stern bulb or with shoe piece. Several examples will shown.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.4
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• pp.1333-1346
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• 1996

As the automation system in manufacturing field works more efficientely, the automation scheme is applied to many areas. In order to reduce the entire manufacturing, cost the design process must be automated. However, design process is so complicated, it is very difficult to construct the design automation system. The axiomatic approach to design provides a general theoretical framework for all design fields, including mechanical design. The key concepts of axiomatic design are : the existence of domains, the characteristic vectors within the domains that can be decomposed into hierarchies through zigzagging between the domains, and the design axioms. Using this approach, the glass bulb design process was analyzed and the design automation software was developed. Through menu display, a user can select or furnish the design input and generate the drawing with ease.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.205-212
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• 1988

The effect of physicochemical characteristics on the freezing point depression of garlic bulb was studied to examine the reasons of cryoprotectivity in garlic bulb stored at subzero temperature. The composition of fresh garlic was characterized by having high soluble solids($40^{\circ}$ Brix; 90% on dry basis), comparing with $10^{\circ}$ Brix in case of other fruits and vegetables. Soluble solids were composed of 70% sugars, 20% protein, and 10% insoluble solids(including 3% of ash, 3% of crude fiber, and 4% of fat). The main component of sugars in garlic was fructosan with 1-29 degree of polymerization(D.P) and the fructosan of 4-5 D.P was over 50% of total fructosan. Freezing point of garlic bulb, which is a parameter of cryoprotectivity, was depressed as the concentration of soluble solids increased, and as the D.P value decreased in the same concentration of soluble solids.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.3
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• pp.235-240
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• 2007

Recently, energy saving buildings are interested in many parts and many types of thermal insulating materials have been developed. The temperature and brightness of inside and outside building are influenced by weather change and sun's brightness and location. The location of building considering the natural daylight is an important parameter to build a building. To modeling the natural daylight, we used 342 electric bulbs which mean artificial daylight. All these bulbs are installed on dome shape frame. Especially it is focused on the luminosity control of each bulb in this paper. The luminosity of bulbs is controlled by phase control using several PIC microprocessors and triacs.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.2
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• pp.151-163
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• 2006

Although various methods for effective modeling of pre-reinforced zones have been suggested for numerical analysis of large section tunnels, tunnel designers refer to empirical cases and literature reviews rather than engineering methods because ones who use commercial programs are unfamiliar with a macro-scale approach in general. Therefore, this paper suggests a simple micro-scale approach combined with the macro-scale approach to determine equivalent design parameters for effective numerical modeling of pre-reinforced zones in tunnel. This new approach is to determine the equivalent stiffness of pre-reinforced zones with combination of ground, bulb, and steel in series or/and parallel. For verification, 3-D numerical results from the suggested approach are compared with those of a realistic model. The comparison suggests that two cases make best approximation to a realistic solution: One is related to the series-parallel stiffness system (hereafter SPSS) in which bulb and steel are coupled in parallel and then connected to the ground in series, and the other is the series stiffness system (hereafter SSS) in which only bulb and steel are coupled in series. The SPSS is recommended for stiffness calculation of pre-reinforced zones because the SSS is inconvenient and time-consuming. The SPSS provides slightly bigger vertical displacement at tunnel crown in weathered rock than other cases and give almost identical results to a realistic model for horizontal displacement at tunnel spring line and ground surface settlement. Displacement trends on weathered rock and weathered soil are similar. The SPSS which is suggested in this paper represents the behavior mechanism of pre-reinforced area effectively.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.2
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• pp.75-80
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• 2016

There are three types of dehumidification systems : refrigeration dehumidification method, desiccant dehumidification method and hybrid dehumidification method. The first method involves removing moisture by condensation below the dew point, the second method involves absorption by a desiccant material and the last is an integration method. However, the refrigeration dehumidification system consumes too much power and controlling the humidity ratio is difficult. The desiccant dehumidification system uses less power but it has problems of environmental pollution. The hybrid dehumidification system has the disadvantage of a high initial cost. On the other hand, the energy consumption of the membrane based dehumidification system is lower than for the refrigeration dehumidification system. Also, it is an environmentally friendly technology. In this study, the performance parameters are evaluated for the dehumidification system using a hollow fiber membrane. Available area, duct side dry-bulb temperature, sweep gas flux (flow rate) and LMPD (Log Mean Pressure Difference) were used as the performance parameters.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.6
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• pp.609-615
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• 2000

The energy conservation is one of the most important issues in recent years. Especially, the energy conservation through improved control strategies is one of the most highly possible area to be implemented in the near future. The energy conservation of the ice storage system can be accomplished through the improved control strategies. A real time building load prediction algorithm was developed. The expected highest and the lowest outdoor temperature of the next day were used to estimate the next day outdoor temperature profile. The measured dry bulb temperature and the measured building load were used to estimate system parameters by using the on-line weighted recursive least square method. The estimated hourly outdoor temperatures and the estimated hourly system parameters were used to predict the next day hourly building loads. In order to see the effectiveness of the building load prediction algorithm, two different types of building models were selected and analysed. The simulation results show less than 1% in error for the prediction of the next day building loads. Therefore, this algorithm may successfully be used for the development of improved control algorithms of the ice storage system.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.829-838
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• 2015

Garlic (Allium sativum L.), one of the oldest cultivated crops, is the most widely used Allium species belonging to the family Lilliaceae. In this study, growth characteristics, photosystem II activity, and antioxidative enzyme activity were investigated in five temperatures ($10-30^{\circ}C$) during early growth stage of garlic to determine the optimum temperature for cultivation and assess the effects of high temperature on early growth of garlic. Vegetative growth (e.g., shoot height, number of leaves) of garlic plants was greater in the temperature ranges of $15-25^{\circ}C$. However, dry weight (of shoot, bulb, and total plant) of garlic was significantly greater at $20^{\circ}C$, compared to either below or above $20^{\circ}C$. $F_v/F_o$ and $F_v/F_m$ values were highest at $15-20^{\circ}C$, and decreased above $25^{\circ}C$. The chlorophyll a fluorescence induction OKJIP transient was also considerably affected by high temperature; the fluorescence yields $F_i$ and $F_P$ decreased considerably above $25^{\circ}C$, with the increase of $F_k$ and $W_k$. Activities of catalase and superoxide dismutase in leaves and peroxidase in roots were high in $20-25^{\circ}C$, and decreased significantly in $30^{\circ}C$. These results indicate that a growth temperature of $30^{\circ}C$ inhibits early growth of garlic and that it is desirable to culture garlic plants near $20^{\circ}C$. Fluorescence parameters such a $F_v/F_o$, $F_v/F_m$, $F_k$, $ET_o/CS_m$, and $PI_{abs}$ were significantly correlated with dry weight of whole garlic plants (p < 0.01), indicating that these fluorescence parameters can be used for early assessment of high temperature effects even though the damage to the plant is not very severe.