• 대한후두음성언어의학회지
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• 제28권1호
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• pp.38-42
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• 2017

Background and Objectives : Globus pharyngeus is a sensation of foreign body in the throat. There are many studies evaluate relationships between globus pharyngeus and organic diseases such as laryngopharyngeal reflux, esophageal motility disorders as well as psychotic causes. But, Also many patients without etiologic causes complain of globus sensation. The authors performed a study that evaluate association between oral water intake and symptoms of globus sensation on the basis of a belief that pharyngeal dehydration due to lack of oral water intake causes globus sensation. Materials and Methods : A survey using visual analogue scale to evaluate symptoms was performed with 73 patients with globus pharyngeus. Results : Patients who drink water less than 500 mL per day (p=0.04) and less than five times per day (p=0.02) were improved after 6 months due to education and doctor's recommendation. Conclusion : Frequent and enough water intake should be recommended to resolve symptoms of globus sensation.

• 전기학회논문지
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• 제62권9호
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• pp.1223-1227
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• 2013

If the factory test efficiency and field operation efficiency of water turbine are different from each other, issues for efficiency warranty can be raised. So, This paper shows the result for comparative analysis of field operating efficiency vs plant testing efficiency of the water turbine generator installed in agricultural reservoir. The efficiency of the induction generator is analyzed by the change of rotational speed with the parameter obtained by test, the efficiency of water turbine is calculated by the change of head with the design flow. Efficiency deviation of induction generator is lower but the variation of developed power is pretty high near the rated speed and the efficiency variation of water turbine is high by the fluctuation of head for constant flow. It was found that factory test efficiency and total efficiency of water turbine generator calculated according to the rotational speed are very close.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.257-260
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• 2002

The main purpose of this research is to find suitable treatment methods of wastewater effluent for artificial recharge. For this purpose, we search the effluent quality of wastewater treatment plant and possibility of additional filtration process. Particles ranged 2 ~ 5 ${\mu}{\textrm}{m}$ and 15~20 ${\mu}{\textrm}{m}$ in "T" WWTP(Waste Water Treatment Plant) effluent were relatively dominant. In dual-media filtration system operation, head-loss development of column 1 was about two times faster than column 2, and head-loss development within 5 cm from surface was very important factor in operation, Conclusively, for the stable filtration and running time of 1.5~2 day, influent turbidity must keep 5 NTU or below, and filtration system must operated at 280 m/day or below. After filtration of WWTP effluent, water quality reached satisfactory level. This water has potential of agricultural reusing, flushing water in building, recharging water to river or stream at dry season and artificial recharge of ground water.und water.

• 대한조선학회논문집
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• 제49권1호
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• pp.6-13
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• 2012

As ocean resources in shallow water areas are being exhausted, deep sea development is becoming common these days. Therefore floating type offshore structures are more competitive than fixed type structures, and FPSO is the most popular one these days. FPSO's are generally operated in a specific region and positioned to meet mostly head or bow waves in order to reduce roll motions. However this makes these vessels more vulnerable to green water around the bow region, and therefore the bow shape must be properly designed to mitigate green water damage. In the present study, experimental results for three different FPSO bow shapes in regular head waves were analyzed and compared to each other. Also CFD computations were carried out as a sample validation case for the database built for CFD code validation.

• 한국해양공학회지
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• 제23권5호
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• pp.9-14
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• 2009

The green water on deck has many harmful effects on the vessel in rough seas such as damages to hull structures, damages to cargos, increase of the downtime, decrease of the stability, and so on. Floating Production Storage and Offloading vessels (FPSOs) are operated in a specific location and are normally positioned to meet mostly head or bow waves in order to reduce the roll motions. But this makes FPSOs more vulnerable to green water around the bow region therefore the bow shape should be properly designed to mitigate the green water damage. In this paper, experimental results in regular head waves for three kinds of bow shapes are compared and some design considerations are proposed, with the building a database for computational fluid dynamics (CFD) validation in mind.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.138-138
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• 2021

Flash floods are one of the types of natural hazards which has severe consequences. Flash floods cause high mortality, about 5,000 deaths a year worldwide. Flash floods usually occur in mountainous areas in conditions where the soil is highly saturated and also when heavy rainfall happens in a short period of time. The magnitude of a flash flood depends on several natural and human factors, including: rainfall duration and intensity, antecedent soil moisture conditions, land cover, soil type, watershed characteristics, land use. Among these rainfall intensity and antecedent soil moisture, play the most important roles, respectively. Flash Flood Guidance is the amount of rainfall of a given duration over a small stream basin needed to create minor flooding (bank-full) conditions at the outlet of the stream basin. In this study, the Sejong University Rainfall-Runoff model (SURR model) was used to calculate soil moisture along with FFG in order to identify flash flood events for the Geum basin. The division of Geum river basin led to 177 head-water catchments, with an average of 38 km². the soil moisture of head-water catchments is considered the same as sub-basin. The study has measured the threshold of flash flood generation by GIUH method. Finally, the flash flood events were used for verification of FFG. The results of the validation of seven past independent events of flash flood events are very satisfying.

• 한국화재소방학회논문지
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• 제18권4호
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• pp.35-41
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• 2004

스프링클러 헤드의 살수 특성은 화재의 초기 진화 성능을 결정짓는 매우 중요한 요소이며, 이는 헤드노즐의 형상에 크게 좌우된다. 본 연구에서는 국내 시장점유율이 가장 높은 4개 제조사의 헤드 제품군에 대하여 방수계수 값과 방향성 살수 분포 특성을 규명하였다. 방수계수는 모두 기준 값을 상회하였지만, 헤드 종류별로 동일한 설계 값을 가짐에도 불구하고 큰 차이를 보이는 것으로 나타나 제품 간 품질차이가 큰 것으로 나타났다. 다만, 방수계수는 압력변화에 관계없이 비교적 일정하게 나타났다. 방향별 살수 분포 특성은 일부 헤드 샘플의 경우 매우 심각한 편향 분포를 나타냄으로써 성능개선 연구가 시급한 것으로 판단되었다

• 한국인쇄학회지
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• 제28권2호
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• pp.87-99
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• 2010

The ink which is left by sealed more than 6 months, it clogs head nozzle of machine due to precipitation and coagulation. In addition, if you stop printing about 3~4 hours in the middle of printing work, the head nozzles of printer could be naturally clogged. To prevent of this situation, worker should implement cleaning and checking head nozzle before hands. When the nozzle is clogged in the middle of work, running a head cleaning mode can clear the clogged nozzle. Yet, large amount of waste inks which are passed clogged nozzle will be remained after cleaning. It would be very nice that ink companies take the waste ink back by green marketing, but none of them are doing it currently. The purpose of this research is that making a black water-based recycle ink by waste inks which are left of nozzle clogging or passed expiration date. This recycle ink will improved working environment and reduce cost of disposing waste inks. Furthermore, it is very environment friendly and economical. It is called a recycle ink which is water-based black ink made by waste inks.

• 한국농공학회지
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• 제24권2호
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• pp.49-55
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• 1982

The purpose of this study is to classify the factors influenced on the damages of head works suffered from the storm flood occurred on July 22 1980 in both Musim and Bochong rivers and to find out an integral counter measures against the causes influenced on the disaster of head works in the engineering aspect of planning, design, construction and maintenance. In this survey, number of samples was taken 25 head Works, and the counter measures against the causes of their disasters summarized was as follows, 1. In the aspect of planning a. As the flood water level after the establishment of head works is more increased than the level before setting of head works owing to having more gentle slope of river bed between the head works than nature slope of river bed. Number of head works should be reduced for the appropriate annexation of them b. In the place where head works is established on the curved point of levee, the destruction of levee becomes severe by the strong deflective current. Therefore the setting of head works on the curved point should be kept off as long as possible and in case of unavoidable circumstances the construction method such as reinforced concrete wall or stone wall filed with concrete and anchored bank revetments should be considered. 2. In the aspect of design a. As scoring phenomena at up stream is serious around the weir Where the concentration of strong current is present in such a place, up stream apron having impermeability should be designed to resist and prevent scoring. b. As the length of apron and protected bed is too short to prevent scoring as down stream bed, the design length should be taken somewhat more than the calculated value, but in the case the calculated length becomes too long to be profitable, a device of water cushion should be considered. c. The structure of protected river bed should be improved to make stone mesh bags fixed to apron and to have vinyl mattress laid on river bed together with the improvement for increasing the stability of stone mesh bags and preventing the sucked sand from the river bed. d. As the shortage of cut-off length, especialy in case of the cutoffs conneting both shore sides of river makes the cause of destruction of embankment and weir body, the culculation of cut-off length should be taken enough length based on seepage length. 3. In the aspect of design and constructions a. The overturing destruction of weir by piping action was based on the jet water through cracks at the construction and expansion joints. therefore the expansion joint should be designed and constructed with the insertion of water proof plate and asphalt filling, and the construction joint, with concaved shape structure and steel reinforcement. b. As the wrong design and construction of the weep holes on apron will cause water piping and weir destruction, the design and construction of filter based on the rule of filter should be kept for weep holes. c. The wrong design and construction of bank revetment caused the severe destruction of levee and weir body resulting from scoring and impulse by strong current and formation of water route behind the revetment. Therefore bank revetment should be designod and constructed with stone wall filled with concrete and anchored, or reinforced concrete wall to prevent the formation of water flow route behind the wall and to resist against the scoring and impulse of strong stream. 4. In the aspect of maintenance When the damaged parts occurred at head works the authorities and farmers concerned should find and mend them as soon as possible with mutual cooperation, and on the other hand public citizen should be guided for good use of public property.

• 한국화재소방학회논문지
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• 제30권3호
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• pp.86-93
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• 2016

드렌처 헤드의 형상이 화재확산 차단을 위한 수막의 유동특성 및 복사 감쇠에 미치는 영향에 관한 실험적 연구가 수행되었다. 헤드의 형상인자로서 오리피스 출구와 반사판의 거리(h) 그리고 반사판의 직경(D)이 변화되었으며, 오리피스의 직경(d)은 고정되었다. 주요 결과로서, h의 증가는 방수량과 분사각의 증가를 가져오지만, D의 증가에 따라 분사각의 변화는 감소한다. D의 증가는 방수량 증가에 매우 작은 영향을 미치며, 분사각의 큰 감소를 초래한다. 또한 D의 증가는 보다 편평한 수막 패턴을 생성시킬 수 있지만, 분사각 내의 더 낮은 액적 균일도를 가져온다. 작동압력의 증가에 따라 평균 액적직경은 크게 감소하지만, 일정한 압력 조건 하에서 헤드 형상변화는 액적직경 변화에 큰 영향을 주지 않는다. 마지막으로 일정한 작동압력의 조건에서 드렌처 헤드의 복사 감쇠효과는 h 및 D의 변화에 따른 방수량과 액적 균일도에 의해 각각 영향을 받는 것으로 확인되었다.