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Water vapor in high-mass star-forming regions and PDRs: the Herschel/HIFI view

  • Choi, Yunhee;van der Tak, Floris F.S.;van Dishoeck, Ewine F.;Bergin, Edwin A.
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.42.2-43
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    • 2015
  • Massive stars play a major role in the interstellar energy budget and the shaping of the galactic environment. The water molecule is thought to be a sensitive tracer of physical conditions and dynamics in star-forming regions because of its large abundance variations between hot and cold regions. Herschel/HIFI allows us to observe the multiple rotational transitions of H2O including the ground-state levels, and its isotopologues toward high-mass star-forming regions in different evolutionary stages. Photodissociation regions (PDRs) are also targeted to investigate the distribution of water and its chemistry. We present line profiles and maps of H2O using data from two guaranteed-time key programs "Water In Star-forming regions with Herschel" and "Herschel observations of EXtra-Ordinary Sources". We analyze the temperature and density structures using LTE and non-LTE methods. We also estimate turbulent and expansion velocities, and abundance of water in the inner and outer envelopes using the 1D radiative transfer code. Around high-mass protostars we find H2O abundances of ~10-8-10-9 for the outer envelope and ~10-4-10-5 for the inner envelope, and expansion and turbulent velocities range from 1.0 km s-1 to 2.0 km s-1. The abundances and kinematic parameters of the sources do not show clear trends with evolutionary indicators. The Herschel/HIFI mapping observations of H2O toward the Orion Bar PDR show that H2O emission peaks between the shielded dense gas and the radicals position, in agreement with the theoretical and the observational PDR structure. The derived H2O abundance is ~10-7 and peaks at the depth of AV ~8 mag from the ionization front. Together with the low ortho-to-para ratio of H2O (~1) presented by Choi et al. (2014), our results show that the chemistry of water in the Orion Bar is dominated by photodesorption and photodissociation.

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Carcass Characteristics and Qualitative Attributes of Pork from Immunocastrated Animals

  • Caldara, Fabiana Ribeiro;Moi, Marta;Santos, Luan Sousa Dos;Paz, Ibiara Correia De Lima Almeida;Garcia, Rodrigo Garofallo;Naas, Irenilza De Alencar;Fernandes, Alexandre Rodrigo Mendes
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.11
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    • pp.1630-1636
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    • 2013
  • An investigation was carried out to assess the carcass characteristics and meat quality aspects of immunocastrated male pigs of medium genetic potential for lean meat deposition in carcass (53 to 55%). When the crossbred Large White x Landrace pigs (n = 45) were 70 days old, they were distributed in a totally randomized design in three treatments (castrated males, females and immunocastrated males) with three replicates of five animals. The pigs were slaughtered when they were 140 days old. Carcass temperature and pH were recorded twice, at 45 min and 24 h after slaughter. The carcasses were evaluated for hot and cold carcass yield, commercial cuts yield, length and depth, back fat thickness, loin eye area and lean meat percentage. The Longissimus dorsi muscle was extracted for analysis of color ($L^*$, $a^*$, $b^*$), exudate loss, cooking loss and centesimal and sensorial analysis of the meat. There were no significant differences for the evaluated parameters between castrated males, immunocastrated males and females, except for backfat thickness between the 7th and 8th thoracic vertebra and the point P2 (lower for immunocastrated males) and carcass temperature at 45 min post slaughter (higher in immunocastrated males), however, this did not interfer with the rate of pH decrease post mortem and the meat quality. The results from this research did not indicate a benefit of immunocastration on carcass characteristics of pigs of medium genetic potential for lean meat deposition in carcass, when compared to surgical castration.

Radical Scavenging and Anti-obesity Effects of Various Extracts from Turmeric (Curcuma longa L.) (추출용매에 따른 울금 추출물의 라디칼 소거능 및 항비만 효과)

  • Park, Jeongjin;Lee, Jeongmin;Jun, Woojin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.12
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    • pp.1908-1914
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    • 2013
  • In the present study, the levels of phenolic compounds and flavonoids, as well as activities of radical scavenging (DPPH and ABTS radical scavenging activity) and anti-obesity were assessed with cold water (CLC), hot water (CLH), and methanolic (CLM) extracts of Curcuma longa L. (turmeric). Our results showed that the phenolic compounds of CLC, CLH and CLM were $3.68{\pm}0.80%$, $3.94{\pm}0.74%$ and $9.01{\pm}0.73%$, respectively. The DPPH and ABTS radical scavenging activities of the CLM were significantly higher than that of the water extracts (CLC and CLH). During the adipocyte differentiation, the treatment of CLM more significantly inhibited lipid accumulation in 3T3-L1 cells than that of the water extracts. These results indicate that the stimulation of radical scavenging potential and the inhibition of adipogenesis were brought on by the lipophilic compounds of turmeric.

Bikinis in the United States, from 1946 to the 1960s (비키니 수영복에 관한 연구 -1946년에서 1960년대까지 미국을 중심으로-)

  • Lee, Yhe-Young
    • Journal of the Korean Society of Costume
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    • v.56 no.7 s.107
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    • pp.142-151
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    • 2006
  • Bikini, a brief two-piece bathing suit revealing the wearer's navel, was first introduced in Paris, in 1946. However, it was not until the late 1950s that Americans were ready to adopt bikinis. Therefore, I focused on the following research questions to understand the popularization process of bikinis in the United States, from 1946 to the 1960s: 1. Why were Americans initially hesitant to adopt the bikini? 2. What were the factors that influenced the popularization of the bikini among Americans in the late 1950s? Primary sources including Bazaar. Madmoiselle, Vogue, The New York Times, and Life were reviewed. I referred to secondary sources on the history of fashion and American popular culture to interpret primary sources. According to the primary sources, Americans were hesitant to adopt the bikini, partly due to the excessive demand on the wearer's figure. However, the conservative social atmosphere during Cold War would not accept immorality and obscenity which would threaten America's future. Therefore, the campaigns against the sex industry, which developed prominently after WWII, predominated American society during the 1950s. Under this atmosphere, a small number of pictures and articles on bikinis appeared in the primary sources. Bikinis were only found in advertisements including sun lotions and hair removers. However, American society had to accept the change in sexual mores by the end of the 1930s. Body-revealing fashions including miniskirts, hot pants, and see-through material reflected the change in social convention. By the end of the 1950s, the number of pictures and articles on bikinis also began to increase in the primary sources. More Americans adopted bikinis with the increasing number of private pools and European trips. The vogue of sun-tanning and movies featuring bikinis further contributed to their popularity in the late 1930s and into the 1960s.

High-efficiency repair welding technology for marine engine components (선박엔진 부품의 고능률 보수용접기술)

  • Kim, Young-Sik;Kil, Sang-Cheol
    • Journal of Advanced Marine Engineering and Technology
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    • v.41 no.1
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    • pp.21-30
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    • 2017
  • Of the marine engine components, the piston crown and exhaust valve are repaired most frequently. These works are conducted through conventional welding processes such as GTAW or SAW, domestically in marine engine repair factories. New high-efficiency welding or overlay processes such as tandem SAW, tandem MAG, hybrid TIG-MIG welding, pulsed-GMAW, CMT welding, and super TIG welding have been developed recently. Moreover, the plasma transfered arc (PTA) process is an efficient spray method for overlaying on the exhaust valve. In this review paper, the new high-efficiency repair welding methods are introduced for marine engine components. The problems due to repair welding for marine engine components are also presented.

Past and Present Meteorological Stress in Crop Production and Its Significance (농작물의 기상재해와 대책)

  • Eun-Woong Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.27 no.4
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    • pp.291-295
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    • 1982
  • The biosphere of the earth is not only about to overpass the limit to meet the food demand of the world but also the stability of its food production has been also jeopardized by the disasters and pests, especially by the unpredictable weather disasters. In addition the agricultural and industrial pollution against biosphere aggravates the unstability of agricultural production and constitutes a threat in securing the food of the world. In Korea the yield level of crops has been greatly enhanced by the improved agrotechnologies and varietal improvement, but the yield variability due to unfavorable weather events and pests remained unchanged with the change in time. Among weather-related disasters the drought and flood damages has occurred most frequently and impacted most greatly on the agricultural production and its stability. During last decade (1970-l980) the rice production experienced the average annual loss of 0.544 million metric ton which was composed of 0.21 million M/T by climatic disaster, 0.21 million M/T by disease and 0.12 million M/T by insects, and the annual loss of upland crop production from climatic disasters amounted to 0.06 million metric tons. Especially in 1980, the global climatic disasters due to cold or hot temperature endangered the agricultural production all over the world and also the rice production of Korea recorded the unprecedented yield reduction of about 30 percent due to cool summer weather. Nowadays, the unusual weather conditions are prevaling throughout the world, and agro-meteologists predict that the unpredictable cool summer and drought will often attack the rice and other crops in 1980's. To meet the coming weather unstability and to secure the stable crop production, multilateral efforts should be rendered. Therefore, the Korea Society of Crop Science, which commemorates the 20th anniversary of its founding, prepared the symposium on Meteological Stress in Crop Production and its Countermeasures to discuss the decrease in agricultural production due to weather-related disasters and to devise the multilateral counter-measures against the unfavorable weather events.

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A study on post-formula instruction of Kyejitang(桂枝湯) (계지탕(桂枝湯) 방후주문(方後註文)에 관한 연구(硏究))

  • Kim, Kang;Meang, Woongjae
    • The Journal of Korean Medical History
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    • v.23 no.1
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    • pp.23-41
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    • 2010
  • Greater yang disease(太陽病) is a syndrome induced by peripheral obstruction. One of them is "wind stroke(中風)" with the obstruction in lymphatic system. The other obstruction appearing on circulatory system is called "cold damage(傷寒)." Kyejitang(桂枝湯) is the formula prescribed for greater yang wind stroke pattern(太陽中風證) which is caused by peripheral lymphatic duct obstruction. Ramulus Cinamoni acts as a vasodilator and Radix Paeoniae relieves the abdominal tension. They make blood move to the internal organ and this can remove the retention of peripheral lymphatic system. Covering the patient with a blanket and getting him/her to have hot and thin rice gruel causes slight Diaphoresis, contributing to relieving the retention of lymphatic system. Disharmony between nutrient and defense(營衛不和) means that pressure becomes different between lymphatic system and vascular system. Kyejitang(桂枝湯) is called releasing muscles formula(解肌劑) because it can resolve such pressure difference. Diaphoresis is not a means to eliminate pathogenic qi(邪氣) from the body. That is the syndrome proving that the body fluid has moved around when disordered fluid distribution is corrected. Therefore, diaphoresis should be induced weakly all the time. If diaphoresis is induced excessively, body fluid will move more than desired and then illness cannot be cured. In Sanghanlun(傷寒論), dispersing drugs aim at addressing the retention in the exterior field, but it actually applies to the entire exterior and interior to make body fluid move. Therefore, diaphoresis does not just act on exterior field, and freeing the stool does not only apply to interior field. Distribution of body fluid changed by pathogenic qi(邪氣) influences the whole body because the human body has a closed circulatory system. Sanghanlun(傷寒論) has included treatments for pathogenic disease. However, its value should not be limited to pathogenic disease. It is because controlling blood flow by sending body fluid to the place a doctor wants is certainly worth using for treatment of non-exogenous disease or chronic illnesses.

Oscillatory Motion of Natural Convective Flow in Partially Divided Square Enclosure (수평격판을 갖는 4각형 밀폐공간내에서 자연대류의 진동유동)

  • 김점수;정인기;송동주
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.10
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    • pp.1963-1970
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    • 1992
  • An oscillatory motion of the natural convection in a two dimensional, partially divided square enclosure heated from below, and fitted with a partition is investigated numerically. The enclosure was composed of the lower hot and the upper cold horizontal walls and the adiabatic vertical walls, and a partition was situated perpendicularly at the mid-height of the one vertical insulated wall. The governing equations are solved by using the finite element method with Galerkin method. The computations were performed with the variation of the length and the thermal conductivity of the partition, and Rayleigh number based on the temperature difference between horizontal walls and the enclosure height with water(Pr=4.95). also, the effect of the inclination angles was studied for the transition to the oscillating flow. As the results, it was found that the intensity and frequency of oscillatory motion were affected significantly by the Rayleigh number and the length of partition. The effect of oscillatory motion was weaken with the increase of the thermal conductivity of partition. The inclination angle for the transition was raised with the increase of Rayleigh number and the length of partition.

Humidification model and heat/water balancing method of PEMFC system for automotive applications (자동차용 연료전지 시스템의 가습모델과 열/물균형 유지방법)

  • Jung, Seung-Hun;Yoon, Seok-Ho;Kim, Min-Soo
    • 한국신재생에너지학회:학술대회논문집
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    • 2005.06a
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    • pp.339-344
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    • 2005
  • A PEMFC system model for FCEV was constructed and simulated numerically to examine the heat/water flow of the system and air/fuel humidification process for various operation conditions (ambient pressure /temperature/humidity, operating temperature, power load). We modeled PEMFC stack which can generate maximum electricity of about 80 kW. This stack consists of 400 unit cells and each unit cell has $250cm^2$ reacting area. Uniform current density and uniform operating voltage per each cell was assumed. The results show the flow characteristics of heat and water at each component of PEMFC system in macro-scale. The capacity shortage of the radiator occurred when the ambient was hot $(over\;40^{\circ}C)$ and power level was high (over 50 kW). In spite of some heat release by evaporation of water in stack, heat unbalance reached to 20kW approximately in such a severe operating condition. This heat unbalance could be recovered by auxiliary radiators or high speed cooling fan with additional cost. In cold environment, the capacity of radiator exceeded the net heat generation to be released, which may cause a problem to drop the operating temperature of stack. We dealt with this problem by regulating mass flow rate of coolant and radiator fan speed. Finally, water balance was not easily broken when we retrieved condensed and/or unused water.

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Linear Expansion and Durability of a Composite Boards (MDF Laminated Using Three Selected Wood Veneers) against Drywood Termites

  • CAHYONO, Tekat Dwi;YANTI, Hikma;ANISAH, Laela Nur;MASSIJAYA, Muh Yusram;ISWANTO, Apri Heri
    • Journal of the Korean Wood Science and Technology
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    • v.48 no.6
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    • pp.907-916
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    • 2020
  • This research was conducted to investigate the linear expansion and resistance properties of a composite board (com-ply). This board was made of medium-density fiberboard (MDF) laminated using avocado (Persea americana), mahogany (Swietenia mahogani), and pine (Pinus merkusii) veneers. These three types of veneers were laminated on both surfaces of the MDF using adhesives, namely, epoxy and isocyanate. Glue (250 g·m-2) was spread on the surface, followed by cold press for 3 h with an applied pressure of 15 kg·cm-2. The research result revealed that com-ply exhibited an increased dimensional stability compared with MDF, indicated by reduction in water absorption, thickness swelling, and linear expansion. The com-ply made of the pine veneer and isocyanate adhesive exhibited high density, water absorption, thickness swelling, and screw withdrawal load. The com-ply that exhibited the strongest resistance to drywood termite attacks was the one made of the mahogany veneer and isocyanate adhesive. Moreover, the com-ply that exhibited the biggest weight loss (3.6 %) was made of the pine veneer and epoxy adhesive. The results of this research may facilitate in manufacturing com-ply using the selected veneer and adhesive without the application of hot press.