• Title/Summary/Keyword: Heating Period

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A Study on the Discourse for the Improvement of Living Conditions and Housing through Modern Women's Magazines (일제강점기 여성지에 나타난 생활개선 담론의 경향 고찰 - 주생활 및 부엌개량의 내용을 중심으로 -)

  • Kim, Young-Bum
    • Journal of the Korean housing association
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    • v.22 no.4
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    • pp.51-61
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    • 2011
  • This study aimed to grasp trends of the discourse for improving living conditions carried out since 1920's, when the sense for mending the irrationality of conventional living emerged in various magazines. Among the movement, women intellectuals played an important roles to discuss reforming daily life and unhealthy, inconvenient houseworks. This study found the ideological background and direction of this discourse, and estimated its important role for housing improvement, analyzing the contents of articles published in representative womens' magazines of the modern times. In the discourse, they thought that it was most important to make houseworks brief and efficient, and concentrated on building rational environment for houseworks. As reforming kitchen system, heating system (Ondol) should be separated from cooking system to improve hygienic and economical condition of houseworks. Reformed kitchen would be equipped with new installations for effectiveness, lightened by sunlight through windows, and finished floor with cement and drainage for sanitation. Also, they suggested new ways of living, planning modern houses with reformed kitchen system, thinking about moving path and distance of housewives. This discourse would be a foundation to the change of kitchen system up to now.

Rainfall Characteristics of the Madden-Julian Oscillation from TRMM Precipitation Radar: Convective and Stratiform Rain (TRMM 자료로 분석한 매든-줄리안 진동의 대류성 및 층운형 강수 특징)

  • Son, Jun-Hyeok;Seo, Kyong-Hwan
    • Atmosphere
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    • v.20 no.3
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    • pp.333-341
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    • 2010
  • The stratiform rain fraction is investigated in the tropical boreal winter Madden-Julian oscillation (MJO) and summer intraseasonal oscillation (ISO) using Tropical Rainfall Measuring Mission (TRMM) Precipitation Rader data for the 11-yr period from 1998 to 2008. Composite analysis shows that the MJO/ISO produces larger stratiform rain rate than convective rain rate for nearly all phases following the propagating MJO/ISO deep clouds, with the greatest stratiform rainfall amount when the MJO/ISO center is located over the central-eastern Indian Ocean and the western Pacific. The fraction of the intraseasonally filtered stratiform rainfall compared to total rainfall (i.e., convective plus stratiform rainfall) amounts to 53~56%, which is 13~16% larger than the stratiform rain fraction estimated for the same data on seasonal-to-annual time scales by Schumacher and Houze. This indicates that the MJO/ISO exhibits the organized rainfall process which is characterized by the shallow convection/heating at the incipient phase and the subsequent flare-up of strong deep convection, followed by the development of stratiform clouds at the upper troposphere.

A STUDY ON THE FIXAT10N OF MENTHOL BY CLINOPTILOLITES (Clinoptilolite의 Menthol보유성에 관한 연구)

  • 양광규;조성희
    • Journal of the Korean Society of Tobacco Science
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    • v.6 no.2
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    • pp.117-129
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    • 1984
  • In this study, clinoptilolites were subjected to an array of experimental conditions, such as variations in heating temperature, reaction time, and molarity of acid and bass, and their responses measured. The activation levels were measured by adsorption indexes of toluene and ethyl alcohol and the X-ray spectra of clinoptilolites treated with acid and base. The effect of clinoptilolites on the menthol fuation was estimated by the amount of menthol produced after a given time of storage. The results were as follows: The optimum conditions for the clinoptilolites treatment were found to be IM HCI, IM NaOH, IMHCl-lM NaOH, and IM NaOH-lM HCl at $100^{\circ}C$ for 2 hours. 2. It was noted that clinoptilolites, untreated or treated with HCl, could not be used for the menthol fixation since the catalytic crating of menthol occurred with them. 3. The results from the residual menthol measurement in clinoptilolites after a specific period of storage showed that the best menthol fixation occurred in those treated with IM NaOH. 4. The menthol fuation by cigarettes with mentholated clinoptilolites was far better than that obtained by the use of mentholated tobacco column. 5. Most components in cigrettes smoke were generally reduced by the adsorption to clinoptilolites treated with IM NaOH.

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Drying Characteristics of Large Western Redcedar Timber During Radio Frequency/Vacuum Drying (웨스턴 레드시더 큰 정각재(正角材)의 고주파 진공 건조 특성)

  • Jung, Hee-Suk;Avramidis, Stavros;Cai, Liping
    • Journal of the Korean Wood Science and Technology
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    • v.26 no.3
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    • pp.1-8
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    • 1998
  • Western redcedar timber, 26 by 26cm in cross section and by 200cm long, was dried in a laboratory radio-frequency/vacuum kiln under 65torr of ambient pressure and a fixed frequency of 6.78MHz for the potential rapidly dry large timber. All process data were collected and saved in a computer through a data acquisition system. The temperature in the middle of timber was higher than temperature at the quarter point of timber length and thickness. Temperature gradients developed in the longitudinal and transverse direction of timber. The pressure in the middle of timber was higher than pressure at the quarter point of timber length. The pressure in the middle of timber was lower in the early stage of drying, and higher in the latter stage of drying than pressure at the quarter point of timber thickness. Power density was very highest during heating period and then gradually decreased. The drying curve was approximately linear and the total drying time was 27 hours from an initial moisture content(MC) of 48.6 percent to a final Me of 19.2 percent with only a few mild internal checks in the middle location of timber.

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A Study on the Variation of Ground Water Temperature for Development of Ground Water Source Heat Pump (지하수 열원 열펌프 개발을 위한 지하수 온도의 변화 특성 연구)

  • Nam Hyun Kyu;Kim Youngil;Seo Joung Ah;Shin Younggy
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
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    • v.1 no.2
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    • pp.1-6
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    • 2005
  • Ground water source heat pumps are clean, energy-efficient and environment-friendly systems for cooling and heating. Although the initial cost of ground water source heat pump system is higher than that of air source, it is now widely accepted as an economical system since the installation cost can be returned within a short period of time due to its high efficiency. In a ground water source heat pump system, the variation of the ground water temperature is an important factor that influences the system performance. In this study, variation of the ground water temperature of a single well system is studied experimentally for various operating conditions. When ground water flow exists in the underground, the returned water exchanges heat efficiently with the ground and the temperature of the ground water remains nearly constant. Hence the short circuit problem is minimized. If an active flow of ground water flow exists in the underground, a singe well heat pumps system will be free of short circuit problem and can operate with high performance.

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Development of Automated Diffusion Cell for Determining In Vitro Drug Release from Transdermal Device (경피흡수제형의 in vitro 약물방출실험을 위한 연속확산 장치의 개발)

  • Byun, Young-Rho;Choi, Young-Kweon;Jeong, Seo-Young;Kim, Young-Ha
    • YAKHAK HOEJI
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    • v.34 no.3
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    • pp.161-165
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    • 1990
  • An automated, simple, and reliable method was developed for determining in vitro drug release rate from transdermal delivery dosage forms. The patch is held in position in the heating block by sandwiching it between the middle plate and the bottom plate of diffusion cell. The dissolution profile of the commercially available transdermal scopolamine patch was determined over a 72-h period, and the results were compared with those obtained with other methods; paddle-over-disk method, reciprocating method, and diffusion cell method. It was demonstrated that the flow-through method is equivalent in terms of release rate profile and accumulated released drug amount over the lifetime of the dosage form tested. Also this method is simple, reliable and reproducible. Therefore, this technique can be used in a quality control for assuring product uniformity.

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A Cost Analysis of the Heat Recovery Ventilator under Various Condition (열회수형 환기장치의 운전조건에 따른 경제성 평가에 관한 연구)

  • Kang, Tae-Wook;Koh, Jae-Yoon
    • Journal of the Korean Solar Energy Society
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    • v.26 no.1
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    • pp.21-28
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    • 2006
  • Changes in building construction methods and repairing of older buildings have reduced infiltration rate. Synthetic materials, release airborne particles and uneven healthy odor are increased. For preventing pollutants introduce fresh outdoor air into the building, simply letting fresh outdoor air into building, however, Is not a cost-effective way to ventilation. When additional ventilation is added to an existing HVAC system, the heating and cooling equipment, often cannot handle the increased load. A HRV provides a way to minimize in energy costs while introducing fresh air to a building. In this study, the economical research of HRV, made of three types of materials, are conducted. Heat recovering characteristics are studied at seasonal outdoor air conditions based on the outdoor air property condition at, Seoul in 2002. As a results, the average sensible effectiveness is 0.75 in the sensible heat exchanger and average total effectiveness is 0.65 in the total heat exchanger. The pay back period of the sensible heat exchangers are $3.2{\sim}3.5$ year and it of total heat exchanger is 2.2 years.

Effect of Milling Medium Materials on Mechanical Alloying of Mo-25.0at%Si Powder Mixture (Mo-25.0at%Si 혼합분말의 기계적 합금화에 미치는 밀링매체 재료의 영향)

  • 박상보
    • Journal of Powder Materials
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    • v.5 no.1
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    • pp.64-70
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    • 1998
  • Milling media of steel and partially stabilized zirconia(PSZ) were used to produce $Mo_3$Si by mechanical alloying(MA) of Mo-25.0at%Si elemental powder mixture. The effect of milling medium materials on MA of the powder mixture have been investigated by XRD and DTA. The reaction rate and the end-product noticeably depended upon the milling medium material. The formation of $Mo_3$Si and $Mo_5Si_3$phases by PSZ ball-milling took place after 15 hr of MA and was characterized by a slow reaction rate as Mo, Si, $Mo_5Si_3$ and $Mo_3$Si coexisted for a long period of milling time. The formation of a new phase by steel ball-milling, however, did not take Place even after 96 hr of MA. DTA and annealing results showed that $Mo_5Si_3$ and $Mo_3$Si were formed after heating the ball-milled powder specimens to different temperatures. At low temperatures, Mo and Si were transformed into $Mo_5Si_3$. At high temperatures, the formation of $Mo_3$Si can be partially attributed to the reaction, 7Mo+Si+$Mo_5Si_3$-.4$Mo_3$Si . The formation of $Mo_3$Si and Mo5Si3 phases by mechanical alloying of the powder mixture and the relevant reaction rate appeared to depend upon the milling medium material as well as the thermodynamic properties of the end-products.

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Setting Time and Strength of Slip-form Method Applied Caisson in Low-temperature Period (슬립폼공법 적용된 동절기 케이슨의 온도에 따른 응결시간 및 압축강도)

  • Kim, Bong-Joo;Kim, Jae-Hun;Kim, Chan-Soo;Jo, Ho-Kyoo
    • Journal of the Korean Society of Hazard Mitigation
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    • v.6 no.1 s.20
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    • pp.1-7
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    • 2006
  • In the harbor construction work, caisson is made by slip-form method and curing temperature of caisson concrete need heating in the low-temperature. To get the setting time and compression strength of slip-form method applied caisson at various curing temperature. The curing temperature is divided to the temperature of slip-form and the temperature of second curing curtain. In consideration of setting time, compression strength of concrete and form-removal time, the best temperature is $25^{\circ}C$ at 6 hours slip-form curing time.

A Study on the process of the rancidity of frying oil (튀김과정에서의 변성유생성에 관한 연구)

  • 고영수
    • Journal of the Korean Home Economics Association
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    • v.24 no.4
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    • pp.75-84
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    • 1986
  • The followings are the results of the study on decomposition of oil during the process of frying hot-dogs with soybean oil. First, the oil was heated repeatedly for six days, four hours two session per day. Then the oil was observed when heated under identical condition except for the exclusion of the frying ingredients. And the oil itself was heated constantly for a period of 48 hours. 1. The AV and Carbonyl Value of all frying oils increased with each use (but the oil in which frying ingredients with all other oils) 2. All frying oils showed a tendency to increase initially, then decrease their POV and TBA Number during their heating process. 3. The IV of all oils showed a slight decrease except for oil with frying ingredients added, with showed a substantial decrease. 4. Oil with frying ingredients showed a substantial increase in its oxidized fatty acid level, and others showed a tendency to increase according to the frying time. Decomposition of soybe an oil during the process of frying hot-dogs was studied. Three treatment was performed first, the oil was heated (with hot-dogs) repeatedly four hours in each session, two sessions per day for six days. Second, the oil was heated without hot-dogs under identical condition, Third, the oil was heated constantly for 48 hours.

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