• Title/Summary/Keyword: Dew period

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Impact of Tidal Effects on Fog Events in the Western Coast of Korea (서해 연안 해역에서의 조석현상이 안개에 미치는 영향)

  • An, Hye Yeon;Jeong, Ju-Hee;Kim, Yoo-Keun
    • Journal of Environmental Science International
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    • v.30 no.11
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    • pp.925-936
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    • 2021
  • The study was aimed to investigate the correlation between tidal effects and fog occurrence in Incheon and Mokpo, which are located in the middle and southern coasts of the West Sea of Korea, respectively. The investigation used meteorological data obtained from the automated synoptic observing systems and automatic weather stations and ocean data from tide stations from 2010 to 2019. Fog occurrence frequency was highest at high tide (Incheon, 41%; Mokpo, 45%). During fog event days at high tide, the dew-point depression was low (Incheon, 0.5℃; Mokpo, 0.4℃) and the relative humidity was high (Incheon, 97%; Mokpo, 98%). The wind speed was 2.4 m/s in Incheon and 2.0 m/s in Mokpo, and the main wind directions were west-southwesterly from Incheon and southwesterly from Mokpo. In the fog case study, tidal flats were covered with water before and after the fog started. During the fog period, both stations experienced negative air-sea temperature differences, low dew-point depression, and high relative humidity were maintained, with weak winds forming from the tidal flats to the shore.

A Study on Operating Method to Save Energy from the Adsorption Dryer in the Process of Purifying Compressed Air (고순도 압축공기 제조시스템의 흡착식 Dryer에서 에너지절감을 위한 운전방법에 관한 연구)

  • Kang, Seok-Wan;Chang, Sung-Ho;Kim, Hyeon-Joon;Kim, Sung-Soo;Lee, Yeong-Wook
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.39 no.3
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    • pp.180-191
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    • 2016
  • Optimizing energy usage for maximum efficiency is an essential goal for manufacturing plants in every industrial manufacturing sector. The generation and distribution of purifying compressed air is a large expense incurred in practically all manufacturing processes. Not only is the generation and treatment expensive equipment of compressed air, but frequent maintenance and effective operation is also required. As a plant's compressed air system is often an integral part of the production process, it needs to be reliable, efficient, and easy to be maintain. In this paper, we study to find operating method to save energy from the adsorption dryer in the process of purifying compressed air, which is required for a clean room production site in "A" company. The compressed air passes through a pressure vessel with two "towers" filled with a material such as activated alumina, silica gel, molecular sieve or other desiccant material. This desiccant material attracts the water from the compressed air via adsorption. As the water clings to the desiccant, the desiccant particle becomes saturated. Therefore, Adsorption dryer is an extremely significant facility which removes the moisture in the air $70^{\circ}C$ below the dew point temperature while using a lot of energy. Also, the energy consumption of the adsorption dryer can be varied by various operating conditions (time, pressure, temperature, etc). Therefore, based on existing operating experiments, we have searched operating condition to maximize energy saving by changing operating conditions of the facility. However, due to a short experiment period (from September to October), further research will be focused on considering seasonality.

Management to Prepare Fast Green Suitable for International Golf Tournament in Korea - A Case Study of the Lakeside Country Club - (한국에서 국제 골프 토너먼트 규격에 맞는 빠른 그린 관리 방법 - 레이크사이드 컨트리 클럽을 사례로 -)

  • 장유비;김진관;박장혁;심경구
    • Journal of the Korean Institute of Landscape Architecture
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    • v.31 no.1
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    • pp.66-77
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    • 2003
  • The purpose of this study is to propose a standard putting green management program to prepare fast green suitable for international golf tournaments, and to conform whether the reported green speed model can be applied to the real field situations. The west course of Lakeside Country Club was selected for the case study. This study was initiated on August 1st, 2001 and continued through October 4th, 2001. The results are summarized as follows: 1. Following the long-term schedule, 'penncross' creeping bentgrass turf was mowed at 5.0mm(37days), 4.5mm(8days), 4.0mm(4days), 3.5mm(2days), 3.2mm(2days), 3.0mm(2days), 2.8mm(2days) and the mowing direction was changed daily. Variation of mowing height was reduced to a minimum range. Core aerification with deep tines was applied 19 days prior to the first practice round. Dry sand maintenance was top-dressed 2 times at 1.5mm/$m^2$ on the 17th day and 1.0mm/$m^2$ on the 10th day. Minimum irrigation was applied to keep the turf alive. During the tournament preparation week, dew on the putting greens was removed by using a sponge roller. Following the dew removal, the greens were cut once each morning at a height of 2.8mm. The mower used was the 21 inch working behind mower equipped with a tournament bedknife and 11 reel blades. Following the mowing, the peens were rolled with a light-weight roller in one direction in the morning. Rolling was used as a finishing technique to ensure that the surface was as smooth as possible, and to provide true ball roll and maximum green speed. In conclusion these management practices satisfied the daily green stimpmeter readings required for USGA championship play. 2. During the period of tournament preparation, no damage was observed on the green, but scalping in green edge appeared in about 0.39% of the total area of 18 greens in the west course.

Study of Pallet Scale Modified Atmosphere Packaging Films for Reducing Water Condensation

  • Kim, Jinse;Park, Jong Woo;Park, Seokho;Choi, Dong Soo;Choi, Seung Ryul;Kim, Yong Hoon;Lee, Soo Jang;Park, Chun Wan;Lee, Jung- Soo;Cho, Byoung-Kwan
    • Journal of Biosystems Engineering
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    • v.41 no.2
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    • pp.98-107
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    • 2016
  • Purpose: The aim of this study was to find an appropriate polymer film, which could reduce the water condensation for pallet-size modified atmosphere packaging (MAP). Methods: Five different types of films were selected from several commercialized films. Prior to the real food storage test, plastic boxes with wetted plastic balls were used to simulate the high humidity conditions of real food storage. The initial MAP condition was 5% oxygen and 95% nitrogen, and the $O_2$ concentration, the relative humidity and water condensation inside the films were checked on a daily basis. The MAP test for tomatoes was conducted by using the most appropriate film from the five films examined in this study. Results: Every film except Mosspack(R) indicated a similar variation in the $O_2$ concentration over the course of time. The relative humidity near the surfaces of all the films except nylon-6 approached saturation conditions over time. For three kinds of films, namely, low-density polyethylene (LDPE) film, anti-fogging oriented polypropylene (AFOPP) film, and Mosspack(R), the inner surfaces of the films were fully covered with dew after a storage period of a day. Conversely, an area of 4.5% was covered with dew in the case of the poly lactic acid (PLA) film, and there was no dew inside the nylon-6 film. The pallet-size MAP test for tomatoes was conducted by using the nylon-6 film and there was no water condensation inside the nylon-6 film over three weeks of storage. Conclusions: During the pallet scale MAP, water condensation could cause severe fungal infection and wetting of the corrugated box. Hence, it was important to minimize water condensation. This study showed that the MAP films with high WVTR such as nylon-6 and PLA could reduce the water condensation inside the pallet scale MAP.

Performance Test of Low Temperature Regeneration Polymeric Desiccant Rotor (고분자 제습로터의 저온재생 성능시험)

  • Lee, Jin-Kyo;Lee, Dae-Young;Oh, Myung-Do
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.629-632
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    • 2009
  • The polymeric desiccant rotor is made from the super absorbent polymer by ion modification. The moisture sorption capacity of the super desiccant polymer(SDP) is 4 to 5 times larger than those of common desiccant meterials such as silica gel or zeolite. It is also known that SDP can be regenerated even at the relatively low temperature. To fabricate the desiccant rotor, firstly the SDP was laminated by coating the SDP on polyethylene sheet. Then corrugated and rolled up into a rotor. The diameter, the depth, the dimensions of the corrugated channel, etc. were pre-determined from numerical simulation on the heat and mass transfer in the desiccant rotor. The dehumidification performance was tested in a climate chamber. The relevant tests were carried out at the process air inlet temperature of $32^{\circ}C$, the regeneration air inlet temperature of $60^{\circ}C$ and the inlet dew-point temperature of both the process air and the regeneration air of $18.5^{\circ}C$, when the rotation period is long, the moisture sorption is not effective. In the desiccant rotor developed in this study, the optimum rotation period is found about 350s at the regeneration temperature of $60^{\circ}C$. It was found from further experiments that the optimum rotation tends to decreases as the regeneration temperature increases. Meanwhile, the outlet temperature of the process air deceases monotonically as the rotation period increases.

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DRYING CHARACTERISTINCS OF THIN-LAYERS OF WHEAT AND BARLEY AT NEAR-AMBIENT TEMPERATURE

  • Sun, Da-Wen;J.J.Woods
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.896-905
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    • 1993
  • Thin-layers of wheat and barley are dried at near-ambient temperatures(3.5$^{\circ}C$ -5$0^{\circ}C$) in order to obtain the intrinsic drying data. The well established apparatus was modified to enable it to record all the sample weight data in still air by using a purpose -built automatically controlled sliding valve. The air could be diverted in less than 0.5seconds and a 7 second period was required to attain a steady weight reading. With this apparatus, very smooth drying curves were obtained. The data of sample weight , drying temperature and dew point temperature wee recorded continuously . The drying process was terminated when the moisture content change in 24 hours was less than 0.004 d.b. This was achieved by drying a sample for about a week . The final points were recorded as the dynamic equilibrium moisture content(EMC). The drying data were than fitted to the exponential Newton model and the dynamic EMC data were fitted to the Modified-Chung-Pfost Model . All the fitted parameters are given and comparison is made with previous published data. The comparisons who that the current drying constants are lower than the previous data, the dynamic EMC data obtained for wheat and barely agree with the previous data. The results show that to obtain the drying constant in the exponential Newton model, adequate drying time is necessary.

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Analysis of Conservation Scientific Deterioration Diagnosis and Conservation Environment of the Samjonbul Carved on Rock Surface in Taean, Korea (태안마애삼존불의 보존과학적 훼손도 진단과 보존환경 분석)

  • Eom, Doo-Sung;Jun, Byung-Kyu;Han, Min-Su;Lee, Jang-Jon;Song, Chi-Young
    • 보존과학연구
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    • s.29
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    • pp.19-44
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    • 2008
  • Sam-jon-bul or Three Buddha Image Carved on rock surface which is called Sam-jon-bul in Taean, state-designated national treasure No. 307, made in Baek-je Period, has two Buddha images and one Bodhisattva. The detached part of the Sam-jon-bul from wall rock has been attached through conservation treatment in 1995. Few study has been done on weathering condition of petrological point of view and damage while the surface of the Sam-jon-bul has been under serious weathering (relief) of loosing stone particles, and discoloration. In this study, it was made weathering damage maps, which show physical property of the material and state of damage of Sam-jon-bul, in order to dialogize how far the weathering has been done. It has been considered continuing on-site monitoring as necessity when Sam-jon-bul was covered with dew, which may have been caused by change in weather in and out of the protect building. It is necessary to set up detailed conservation plan for it by doing regular diagnosis on the influence of the protect building and weathering of Sam-jon-bul.

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The Characteristics of the Fog and Analysis of the Advection.Radiation Fog by KLAPS in Honam Region (호남지방 안개 특성 및 KLAPS를 통한 이류.복사안개 사례 연구)

  • Won, Hyo-Sung;Yu, Keun-Gi;Ryu, Chan-Su
    • Journal of Integrative Natural Science
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    • v.4 no.4
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    • pp.298-310
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    • 2011
  • Recently the traffics and transportation hazzards by fog are tremendously Increased. There occurred the greater traffic disaster by Dense Fog of Oct.2006. In this study frequent occurrences of advection fogs centerd over Honam Prov are investigated. Increment of transportation during the Fog period for 1996~2005(decade)are statistically analyzed with Honam Prov.'s fogs. For Honam west coast(Gunsan, Mokpo), inland of Honam(Junju, Gwangju, Suncheon), Honam south coast(Wando, Yepsu), Wind, Dew point, Diff. of air and sea temp. relative humidity are classified between 12 hours before and on time of fog with three Dimensional Analysis System(KLAPS). High frequencies of advection-radiation Fog occurrence in western Coasts except for Suncheon. The application of fog characteristics analyzed by KLAPS for denser fog over the western coast in Fall to Fog prediction and special advisory issues. The advection-radiation fog can occure favorably when the moisture index is less than $2^{\circ}C$, relative humidity is greater than 90%, but the moisture depth is under 1.5 km. In addition when the height of 925 hPa is rising, then fog occurs, but for sinking is disappearing.

Evaluation of the Thermal and Noise Environment in an Ancient Tomb installed a Duct-type HVAC System (공조기가 설치된 고분 내에서의 열 및 음 환경 평가)

  • Park, Jin-Yang;Jun, Hee-Ho;Jun, Yong-Du;Lee, Kum-Bae
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.19 no.3
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    • pp.228-234
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    • 2007
  • Opening an ancient tomb interior can deal fair damage for preservation in long period because of high moisture. In this study, a duct-type HVAC system was installed to preserve an ancient tomb and temperature and humidity was measured to analyze heat environment. Armhole was measured to search whether an ancient tomb receives effects of vibration caused by a duct-type HVAC system. According to the measured data, temperature in an ancient tomb is kept adaptively in conservation regardless of a duct-type HVAC system installation when it rains in summer. The other side, humidity is kept adaptively in conservation when installed duct-type HVAC system. But when it is in natural state, a lot of humidity by dew condensation phenomena. So it needs a duct-type system for an ancient tomb conservation. In the case of vibration, measurement value of 3 satisfy control but Germanic DIN 4150 does not satisfy. Therefore, equip must be such that it can prevent vibration for safety.

Does Financial Behavior Influence Financial Well-being?

  • CHAVALI, Kavita;MOHAN RAJ, Prasanna;AHMED, Riyaz
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.2
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    • pp.273-280
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    • 2021
  • Financial behavior and financial well-being are two closely related aspects of an individual's financial decision making. This study attempts to investigate the extent to which financial behavior influences financial well-being in the Indian scenario. The data is collected using a structured questionnaire from a sample of 150 respondents. The study employs Financial Management Behaviour Scale (FMBS) (Dew & Xiao, 2012) to measure financial behavior. Factor analysis and multiple regression are performed to find the influence of financial behavior on financial well-being. The findings of the study suggest that except for credit commitment all the other behavioral factors like future security, savings and investments, credit indiscipline, and financial consciousness have a significant impact on the financial well-being of an individual in the Indian scenario. The regression coefficients of financial well-being are strongly determined by financial consciousness. The study is a contribution to the existing behavioral studies literature and the model used identifies the factors that influence the financial well-being in the Indian scenario. The study is conducted during the year 2020, so the results could have been influenced by the economic scenario of the period. The results of the study can be used by financial advisors to understand the financial well-being in the Indian scenario.