• Journal of Power Electronics
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• 제17권1호
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• pp.41-55
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• 2017

This study proposes a novel zero voltage transition (ZVT) pulse width modulation (PWM) DC-DC interleaved boost converter with an active snubber cell. All the semiconductor devices in the converter turn on and off with soft switching to reduce the switching power losses and improve the overall efficiency. Through the interleaved approach, the current stresses of the main devices and the ripple of the output voltage and input current are reduced. The main switches turn on with ZVT and turn off with zero voltage switching (ZVS). The auxiliary switch turns on with zero current switching (ZCS) and turns off with ZVS. In addition, the snubber cell does not create additional current or voltage stress on the main switches and main diodes. The proposed converter can smoothly achieve soft switching characteristics even under light load conditions. The theoretical analysis and operating stages of the proposed converter are made for the D > 50% and D < 50% modes. Finally, a prototype of the proposed converter is implemented, and the experimental results are given in detail for 500 W and 50 kHz. The overall efficiency of the proposed converter reached 95.5% at nominal output power.

• 정보와 통신
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• 제4권4호
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• pp.505-524
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• 1987

Nowaday all the countries of the world have studied the various problems caused in operating their own ports efficiently. Ship delay in the port is attributal to the inefficient operation in the navigation aids, the cargo handling, the storage and transfer facilities, and to the inefficient allocation of gangs or to a bad service for ships. Among these elements the allocation of gangs is the predominating factor in minimizing ship's turn round time. At present, in the case of Pusan Port. the labour union and stevedoring companies allocate gangs in every hatches of ships by a rule of thumb, just placing emphasis on minimizing ship's turn round time, without applying the principle of allocation during the cargo handling. Owing to this the efficiency of the cargo handling could not be expected to be maximized and this unsystematic operation result in supplying human resources of much unnecessary surplus gangs. Therefore in this paper the optimal size and allocation of gangs for minimizing the ship's turn round time is studied and formularized. For the determination of the priority for allocation the evaluation function, namely $F=PHi^{n}{\times}(W+H)$, can be obtained; where, PHI : Principal Hatch Index W : Total Cargo Weight represented in Gang-Shifts H : Total Number of Ship's hatches and also for the optimal size of gangs the average number of gang allocated per shift (Ng), namely Ng=W/PHI, is used. The proposed algorithm is applied to Pusan Port and its validity is verified.

• E2M - 전기 전자와 첨단 소재
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• 제7권2호
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• pp.145-151
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• 1994

The multi-dielectric layer SiOz/Si3N4/SiO2(ONO) is used to scale down the memory device. In this paper, the change of composition in ONO layer due to the process condition and the conduction mechanism are observed. The composition of the oxide film grown through the oxidation of nitride film is analyzed using auger electron spectroscopy(AES). AES results show that oxygen concentration increases at the interface between oxide and nitride layers as the thickness -of the top oxide layer increases. Results of I-V measurement show that the insulating properties improve as the thickness of the top oxide layer increases. But when the thickness of the nitride layer decreases below 63.angs, insulating peoperties of film 28.angs. of top oxide and film 35.angs. turn over showing that insulating property of film 28.angs. of top oxide is better than that of film 35.angs. of top oxide. This phenomenon of turn over is thought as the result of generation of surface state due to oxygen flow into nitride during oxidation process. As the thickness of the top oxide and nitride increases, the electrical breakdown field increases, but when the thickness of top oxide reaches 35.angs, the same phenomenon of turn over occurs. Optimum film thickness for scaled multi-layer dielectric of memory device SONOS is estimated to be 63.angs. of nitride layer and 28.angs. of top oxide layer. In this case, maximum electrical breakdown field and leakage current are 18.5[MV/cm] and $8{\times}{10^-12}$[A], respectively.

• 한국전기전자재료학회논문지
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• 제25권7호
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• pp.521-524
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• 2012

We report on variations of electrical properties with different active layer thickness and post-annealing temperature in amorphous In-Ga-Zn-O (IGZO) thin-film transistors (TFTs). In particular, subthreshold swing (SS) of the IGZO-TFTs was improved as increasing the active layer thickness at an given post-annealing temperature, accompanying the negative shift in turn-off voltage. However, as increasing post-annealing temperature, only turn-off voltage was shifted negatively with almost constant SS value. The effect of the active layer thickness and post-annealing temperature on electrical properties, such as SS, field effect mobility and turn-off voltage in IGZO-TFTs has been explained in terms of the variation of trap density in IGZO channel layer and at gate dielectric/IGZO interface.

• IEIE Transactions on Smart Processing and Computing
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• 제6권4호
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• pp.269-275
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• 2017

Automatic vehicle detection is a very important function for autonomous vehicles. Conventional vehicle detection approaches are based on visible-light images obtained from cameras mounted on a vehicle in the daytime. However, unlike daytime, a visible-light image is generally dark at night, and the contrast is low, which makes it difficult to recognize a vehicle. As a feature point that can be used even in the low light conditions of nighttime, the rear lamp is virtually unique. However, conventional rear lamp-based detection methods seldom cope with atypical lamps, such as LED lamps, or flashing turn signals. In this paper, we detect atypical lamps by blurring the lamp area with a low pass filter (LPF) to make out the lamp shape. We also propose to detect flickering of the turn signal lamp in a manner such that the lamp area is vertically projected, and the maximum difference of two paired lamps is examined. Experimental results show that the proposed algorithm has a higher F-measure value of 0.24 than the conventional lamp pairing-based detection methods, on average. In addition, the proposed algorithm shows a fast processing time of 6.4 ms per frame, which verifies real-time performance of the proposed algorithm.

• 대한한방내과학회지
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• 제19권1호
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• pp.353-363
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• 1998

This study involved 30 allergic rhinitis outpatients of section 5 of oriental medical center attached Dong Eui Uni. from April 2, 1997 to May 14, 1998. The results of this study are as follows ; 1. Men were 13 persons (43.33%) and women were 17 persons (56.67%) in sex distinction. 2. In age distinction, 1-10 years (36.67%), 11-20 (23.33%), 41-50 (16.67%), 21-30 (13.33%), 31-40 (6.67%), 61-70 (3.33%) in order of majority. 3. Acupuncture treatment of 16-20 times is 11 persons (36.67%), 26-30 times is 8 persons (26.67%), 21-25 times is 6 persons (20.00%), 11-15 times is 4 persons (13.33%), more than 31 times is 1 persons (3.33%) in order of majority. 4. The symptoms were starting to be improved apprently from more than 26 times, and it was found that the more treatments, the higher favorable turn. 5. Outbreak frequency of symptoms was rhino-cleisis, rhinorrea, ophthalmopathy, headache, sneeze, asthma, dermatitis, and sputum in order of majority. 6. Kamisunohtang of treated prescrptions is the most (80%). The effects were, rhinorrea (83.33 sneeze (66.67%) rhino-cleisis (52.17%), headache (50.00%), ophthalmopathy (20%) in order of favorable turn. 7. Favorable turn of symptoms were rhinorrea, rhino-cleisis, headache, sneeze, sputum, asthma, ophthalmopathy in order.

• 아동학회지
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• 제31권3호
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• pp.199-214
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• 2010

This study examined the effects of siblings, emotional intelligence (E.I.), and conflict solving strategies (integrating-compromising strategy/ dominating strategy) on children's social competence. The subjects were 421 6th graders (231 boys, 190 girls) in Seoul. The children filled out questionnaires on their siblings, E.I., and conflict solving strategies. Their teachers were asked to rate the children's social competence. Mediational analyses were conducted using structural equation modeling. Both integrating-compromising strategies and dominating strategies mediated the relationship between E.I. and social competence. Children with higher E.I. reported that they used more integrating-compromising strategies, which in turn was related to higher social competence. Those who scored low on E.I. reported that they used more dominating strategies, which in turn was related to lower social competence. Although the effects of siblings did not have any direct effects on social competence, it was found to be related to the type of conflict solving strategies most frequently used. Compared to the children with siblings, the children without siblings used more dominating strategies, which in turn contributed to lower social competence.

• 한국전자파학회논문지
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• 제19권5호
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• pp.501-505
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• 2008

이 논문에서는 휴대 장치의 지상파 DMB용 안테나로 다중 권선 loop 안테나를 제안한다. 제안된 안테나는 크기가 작으면서도 지상파 DMB 대역에서 충분한 수신 전력을 확보하도록 권수는 80회, 그리고 직경은 4 mm로 하였으며, 또한 높은 전달 함수 특성을 갖도록 품질 계수를 1로 하였다. 제작된 안테나는 길이가 30 mm로 소형이며, 이득은 약 -15 dBd로 길이 190 mm의 상용 지상파 DMB 모노폴 안테나와 비슷한 수신 능력을 가짐을 측정을 통해 확인하였다.

• 가정과삶의질연구
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• 제9권1호통권17호
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• pp.27-44
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• 1991

The purpose of this study is to investigate the relationship between communication pattern and conflict between old parents and their adult children. For this purose, 380 adult children are surveyed therefore the answers of survey are described by adult children only. The number of old parents turn to be 230 old fathers and 301 old mothers respectively, there numbers have included the case both parents are alive. The data were analysed several method with SPSS and the methods used for the analysis are Factor analysis, one way ANOVA, Scheffe-Test, Pearson's Correlation, Multple Regression. The results of this study are summarizd as follows ; 1) Old parents's communication patterns differ each other and under many variables. 2) In the conflicts between old parents and adult children differ each other and under many variables, too. 3) The relationship between communication patterens and conflict between old parent and adult children turn to be as follows : Two communication styles ie, the autoritarian style and insincere style increse conflicts. Frendly style have negatve affect to conflicts and decreses the conflicts. Sacrifice style is turn to have slightly affect the conflict.

• 한국안전학회지
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• 제24권3호
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• pp.65-70
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• 2009

In-vehicle route guidance information(RGI) systems have been developed with the advancement of the information and communication technologies. However, the RGI is provided by a pre-determined option, drivers occasionally pass the target intersection owing to non- or late- recognizing it. The purpose of this experiment is to examine the position of driver's tum signal operation and intersection recognition approaching at the target intersection which is difficult to identify as a preliminary research on developing the additional RGI connecting with the tum signal control. The field experiment was conducted to measure distances of the turn signal operation and intersection recognition from the target intersection according to driving lanes and landmarks at adjacent intersection. And, glance behavior to the car navigation display was evaluated by using an eye camera. The results indicate that drivers operate the turn signal after confirming a landmark in the case of the intersection with it. However, most case of driving, drivers operate the tum signal at 40 to 50m before coming to the target. To provide the additional RGI, when drivers do not operate the tum signal approaching at the target intersection based on the results, is expected to improve the traffic safety and the comfort for drivers.