• Journal of Korea Port Economic Association
• /
• v.20 no.2
• /
• pp.275-288
• /
• 2004

The rising of east-north economic bloc is notable in world economy due to the rapidly growth of china economy. The China's economic standing is gradually higher and higher because the joining of the WTO at 2001, development of the exterior open-door policy and the expansion of the trade between chain and several nations. Since Korea and China normalized diplomatic ties in 1992, the two have made remarkable progress in bilateral relations in the fields of economy and diplomacy in particular. The amount of Korea's trade with China has increased by over 20% a year on the average because of the development of the economic cooperation of Korea and China. That is to say, China was sixth trade partner by the end of 1993, based on the amount of trade. But China became third partner at 1993, second partner at 2003 and first partner at the first half of 2004, based on the amount of trade. Korea can not trade with China from the Korea's port opening period to Cold War period after second world war. But historically, the two countries have shared a active and long history of trade relations from the ancient times up to now. This is because two countries get near geographically and two countries have a implication of history and culture. Not only had Korea trade with China at prehistoric age, but also at BC 7. We knew that Korea had traded with China very actively at ancient times through the Paekje(Korea's ancient country) people's village at Santung province and Changbogo's trade works. Korea-china trade relation has played an important role for the development of world economy. Therefor, based on reviewing the korea-china trade, I study the historical meaning of the trade at the region of east-north asia.

• Journal of Navigation and Port Research
• /
• v.28 no.6
• /
• pp.491-496
• /
• 2004

The paper describes measurement techniques for an acoustic transfer characteristic of ship's bridge stimulated by a whistle sound The response sounds, according to the opening-shutting conditions of bridge doors for Training Ship ‘SAENURI’, are measured by B＆K 2260D equipment, and then the frequency responses are extracted by B＆K 7830 software. To evaluate the measured transfer characteristic, the 128th order FIR (Finite Impulse Response) filters, containing the different frequency characteristics, are constructed based on the frequency sampling-based design method Using evaluation indexes with six scales, psychological assessments by five subjects are carried out with test sounds which are obtained from convolving the source signal with FIR filters. As results of tests, the test sounds gives $A_S$ 3.3∼4.7 which means the psychological sense of ‘it is almost similar sound as original ones in a real world’, and thus it is clearly seen that the proposed method can be used for the measurement of an acoustic transfer characteristic of ship’s bridge.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.9
• /
• pp.1985-1992
• /
• 2011

PE(Passive Entry) is an automotive technology which allows a driver to lock and unlock door of vehicle without using smart key buttons personally. PG(Pssive Go) is an automotive technology which offers the ability to start and stop the engine when there is a driver in vehicle with smart key. When these two functions are unified, we call it PEG(Passive Entry/Go). LF(Low Frequency) antenna driver which is one of core technologies in PEG is composed of a digital part which processes commands and an analog part which generates sine waveform. The digital part of antenna driver receives commands from MCU(or ECU), and processes requested commands by MCU, and stores antenna-related driver commands and data on an internal FIFO block. The digital part takes corresponding actions for commands read from FIFO and then transfers modulated LF data to analog part. The analog part generates sine waveform and transmits outside through antenna. The designed digital part for LF antenna driver can acomplish faster LF data transmission than that of conventional product. LF antenna driver can be applicable to the areas such as PEG for automotive and gate opening and closing of building.

• Wind and Structures
• /
• v.25 no.1
• /
• pp.79-100
• /
• 2017

The use of wind energy resources is developing rapidly in recent decades. There is an increasing number of wind farms in high wind-velocity areas such as the Pacific Rim regions. Wind turbine towers are vulnerable to tropical cyclones and tower failures have been reported in an increasing number in these regions. Existing post-disaster failure case studies were mostly performed through forensic investigations and there are few numerical studies that address the collapse mode simulation of wind turbine towers under strong wind loads. In this paper, the wind-induced failure analysis of a conventional 65 m hub high 1.5-MW wind turbine was carried out by means of nonlinear response time-history analyses in a detailed finite element model of the structure. The wind loading was generated based on the wind field parameters adapted from the cyclone boundary layer flow. The analysis results indicate that this particular tower fails due to the formation of a full-section plastic hinge at locations that are consistent with those reported from field investigations, which suggests the validity of the proposed numerical analysis in the assessment of the performance of wind-farms under cyclonic winds. Furthermore, the numerical simulation allows to distinguish different failure stages before the dynamic collapse occurs in the proposed wind turbine tower, opening the door to future research on the control of these intermediate collapse phases.

• Journal of the Korean housing association
• /
• v.18 no.1
• /
• pp.27-34
• /
• 2007

The purpose of this study is to examine the characteristics of the plan of fishing village house in the Shikoku district. The research was carried out by field survey and measurement of the traditional house and street system in Higashimachi area of Tomoura. The results of this study are as follows. The traditional house of Higashimachi area is to be taking the plan of Machiya form that is the residence form of a city without being related a fishing village. And the street system is as orderly comparatively as a city. This is not the thing as that is surprised when we think the fact that Higashimachi area has maintained close relation historically with Kyoto, Osaka, etc. However, as for the house of Higashimachi area, the scale is smaller in comparison with Machiya, there is a fundamental difference in terms of the house for the exclusive use of residence. Machiya is the dual constitution of business space and life space. To it the house of Higashimachi area is doing the unitary constitution. Mise is the original opening device (a kind of the front door fitting) of traditional house of Higashimachi area and has the functions that complement narrow space and of offer community space. Finally, the traditional house in this area is equipped with all the residence functions of necessary minimums, although the scale residence is small. It is said that this is the case of a 'small residence' in a Japanese residence.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.26 no.5
• /
• pp.703-709
• /
• 2002

In order to investigate the smoke movement in three dimensional room fires, the center fire, wall fire and corner fire plume in different sized fires were studied experimentally by rectangular pool fire using methanol as a fuel. As the fire size became larger for the center fires placed at the center of the floor, the air flow rate entrained through the opening, average hot layer temperature, flame angle deflected backwards and mean flame height was observed to increase. On the other hand, as the fire size became smaller, the neutral plane height in the door and time reached steady-state was observed to decrease. The average hot layer temperature, mean flame height and doorway neutral plane height obtained from comer fire were higher than those produced by wall fires and center fires. The simple model for describing the effect of walls on the mean flame height was presented. It was shown that the model provides a good description of the present measurements, when used with the assumption by Hansell(1993), that the increase of the average flame height is equal to the ratio of the open to the total perimeters of the trays. Also the two models for predicting the effects of walls on the mean flame height were presented. These models overestimated the measured values of the mean flame height above fuel trays close to a wall and in a corner by approximately 19-26%, respectively.

• Fire Science and Engineering
• /
• v.20 no.1 s.61
• /
• pp.50-54
• /
• 2006

A fire in a subway station platform, completely isolated by screen doors, was numerically simulated to investigate problems in smoke control and find their countermeasures. A part of the platform, $40m{\times}5m$ floor and 3 m high, and a fire of 1 MW were considered, and the smoke extraction system was assumed to start operation at the onset of the fire. For three different values of the exhaust air flow rate, 0.1, 2, and $4m^3/min-m^2$, the distributions of temperature, concentrations of soot and carbon monoxide, and those of visibility were compared. The time-variations of the number of randomly distributed particles in the space were also investigated for the air flow rates to see the efficiency in smoke control. It was shown that smoke control takes time by lack of air supply. It was also confirmed that air supply from the railway to the platform at emergency is needed so that smoke is able to be controlled efficiently, and that opening the doors at the both ends of the platform is desirable until the fire is completely extinguished.

• Fire Science and Engineering
• /
• v.27 no.5
• /
• pp.8-14
• /
• 2013

In the subway, various fires continue to take place across the world. In the Daegu subway accident in 2003, many people were damaged by shortened visibility range caused by toxic gas and smoke. This paper, assuming that a subway fire happens in the Mandeok Station of the subway system in Busan, analyzed different smoke-spreading situations depending on the ventilation situation at its platform (opening of the train doors, operation of ventilation facilities in the tunnel, and working of fire door), using FDS. The calculation proved that it would be more effective to secure evacuation route when the ventilation facilities of the tunnel are not operated, than when they are on. And, it was also found that the case where the doors of the platform to the escape route and only the platform-facing doors of the subway car on fire office are open would be more effective to ventilation than the case where all the doors are open. And, it was found to be important that the fire doors of the platform are working properly.

• Fashion & Textile Research Journal
• /
• v.10 no.6
• /
• pp.1058-1063
• /
• 2008

The use of clothes dryers is increasing in Korea and throughout Asia, because of preference for the drum type washer dryer. Clothes dryers consume more energy than almost any other home appliance. This paper suggests efficient ways for drying laundry with condensing clothes drier. We dried cotton fabrics with the condensing clothes dryers and observed the energy input, temperature and RH of the dryer during the drying process. In the early stages of drying process, the air temperature inside the clothes dryer decreased and the RH and the drying time increased as the weight of fabrics increased. We found that it was important to consider the total weight of the fabrics that included heat-sensitive fibers. It took more than half the drying time and the energy input for a 2.5 kg load that it did for a 5 kg load. Therefore, drying larger one load was more efficient than divided smaller loads, because increasing the weight of the fabrics reduced the energy input per kg of drying clothes. The lower the initial moisture regains of the fabrics were, the lower the energy input and the drying time were. The energy input for spinning after washing was much less than that for drying in the dryer. Consequently, it is more efficient to reduce the moisture content of the clothes by lengthening the spinning time of the washer to reduce the energy consumption and the drying time. During the drying process opening the door twice for 30 seconds each time lowered the air temperature and the RH of the dryer, but did not affect the moisture regain of the fabrics, the drying time, and the energy input.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2004.04a
• /
• pp.55-60
• /
• 2004

The paper describes measurement techniques for an acoustic transfer characteristic of ship's bridge stimulated by a whistle sound. The response sounds, according to the opening-shutting conditions of bridge doors for T／S ‘SAENURI’, are measured by B＆K 2260D equipment, and then extracted the frequency responses by B＆K 7830 software. To evaluate the measured transfer characteristic, the 128th order FIR (Finite Impulse Response) filters, containing the frequency characteristic, are constructed based on the frequency sampling-based design method. Using evaluation indexes with six scales, psychological assessments by five subjects are carried out with test sounds which are convolved source sound and FIR filters. As results of tests, the test sounds gives A／sub s／=3.3∼4.7 which means the psychological sense of 'it is almost similar sound as original ones in a real world', and thus it is cleary seen tint the proposed method can be suit for the measurement of an acoustic transfer characteristic of ship's bridg.