• 한국태양에너지학회 논문집
• /
• 제29권5호
• /
• pp.59-64
• /
• 2009

According to the building regulation U-value limitation of window is $3.3W/m^2{\cdot}K$ in southern regions, while U-value limitation of wall is $0.35{\sim}0.58W/m^2{\cdot}K$. It means that the energy loss through windows is five times more than it through wall. Therefore, this study analyze how much it has affected building energy rating when the insulation performance of windows and walls is changed by building regulation. In conclusion, in order to obtain 2 rating thermal performance of windows is improved more than 10 percent of U-value limitation and it of wall is improved more than 20 percent. The thermal performance of windows is improved more than 20 percent of U-value limitation and it of wall is improved more than 30 percent to receive 1 rating.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2009년도 하계학술발표대회 논문집
• /
• pp.608-613
• /
• 2009

According to the building regulation U-value limitation of window is $3.3W/m^2{\cdot}K$ in southern regions, while U-value limitation of wall is $0.35{\sim}0.58W/m^2{\cdot}K$. It means that the energy loss through windows is five times more than it through wall. Therefore, this study analyze how much it has affected building energy rating when the insulation performance of windows and walls is changed by building regulation. In conclusion, in order to obtain 2 rating thermal performance of windows is improved more than 10 percent of U-value limitation and it of wall is improved more than 20 percent. The thermal performance of windows is improved more than 20 percent of U-value limitation and it of wall is improved more than 30 percent to receive 1 rating.

• 한국전기전자재료학회논문지
• /
• 제18권1호
• /
• pp.30-37
• /
• 2005

The microwave dielectric properties and their related structural characteristics in solid solutions of (1-$\chi$) Ba($Mg_{1/3}$Nb$_{2/3}$) $O_3$-$\chi$La(Mg$_{2/3}$Nb$_{1}$3) $O_3$(BLMN) have been investigated by measuring the dielectric constant($\varepsilon$r), Q value and temperature coefficient of resonant frequency($\tau$f) and by observing the crystal structure using high resolution transmission electron microscopy (HRTEM). Microwave dielectric properties showed characteristic features for specific composition. Dielectric constant($\varepsilon$$_{r}$) showed maximum value at the composition which corresponds to the phase boundary between 1 : 2 ordered and 1 : 1 ordered structure. The increase in $\varepsilon$$_{r}$ may be caused by the rattling of ions by incorporating smaller ions and the disordered structure. The variation of temperature coefficient of resonant frequency($\tau$$_{f}$) was investigated in terms of oxygen octahedra tilting.dra tilting.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제48권4호
• /
• pp.232-240
• /
• 1999

In this study, the $(1-\chi)Ba(Mg_{\fraction one-third}Ta_{\fraction two-thirds}O_3-\chiBa(Co_{\fraction one-third}\Nb_{\fraction two-thirds})O_3$ ceramics($\chi$=0.3,0.4,0.5,0.6) were prepared by the conventional mixed oxide method. The ceramics were sintered at the temperature of $1500~1575^{\circ}C$ for5 hours in air. The BMT-BCN ceramics have a complex perovskite structure, and have peaks of (101), (102), (201), (202) and (212). Increasing the sintering temperature, dielectric constant was increased. Temperature coefficients of resonant frequency of the specimens were decreasing with increasing BCN content. In the case of the 0.7BMT-0.3BCN ceramics sintered at $1575^{\circ}C$ for 5 hours, dielectric constant, quality factor and temperature coefficient of resonant frequency for microwave dielectrics application were a good value of 28, 235500 at ㎓ and -$1.2 ppm/^{\circ}C$, respectively.

• 한국미생물·생명공학회지
• /
• 제49권2호
• /
• pp.201-209
• /
• 2021

Agarwood (Aquilaria spp) has high economic value. However, essential oil production from agarwood is a time-consuming process. Additionally, agarwood leaves have not been utilized even though they contain various bioactive ingredients. In this study, agarwood leaves were fermented using Lactobacillus plantarum ATCC 8014 with or without Stevia (4, 8, and 12%; v/v). The fermented fluid was mixed with maltodextrin (15%; w/v) and subjected to spray drying (inlet temperature, 120℃; outlet temperature, 65-70℃). The contents of polyphenols, polysaccharides, saponins, and flavonoids and the viability of L. plantarum were determined. Fermentation enhanced the levels of bioactive compounds. The contents of polyphenol (69.19 ± 4.05 mg GAE/g of sample), polysaccharide (20.75 ± 0.98 mg GE/g of sample), saponin (305.23 ± 4.21 mg OAE/g of sample), and flavonoid (7.86 ± 0.72 mg QE/g of sample), and the viability of L. plantarum (8.72 ± 0.17 log CFU/ml) were markedly upregulated in the samples containing Stevia (12%; v/v). This indicated that the supplementation of Stevia during fermentation decreases the fermentation time (9 h), upregulates bioactive compound production in agarwood leaves, enhances microencapsulation during spray drying, and increases the viability of L. plantarum under simulated gastric digestion conditions.

• Elastomers and Composites
• /
• 제54권3호
• /
• pp.209-219
• /
• 2019

It is important to analyze crosslink densities of rubber articles because the physical properties are dependent on the crosslink densities. In this paper, analytical techniques for the measurement of crosslink densities of rubber vulcanizates are described. The most widely used method to measure the crosslink density is a swelling method combined with the Flory-Rehner equation. Application of the interaction parameter (${\chi}$) of rubber and swelling solvent is critical because the crosslink density is absolutely dependent on the ${\chi}$ value. Methods for obtaining ${\chi}$ employ not only solubility parameters of the polymer and swelling solvent but also inverse gas chromatography (IGC). The solubilities of rubbers can be obtained using micro differential scanning calorimetry (${\mu}DSC$), intrinsic viscosity measurement, and UV-visible spectroscopy. Nuclear magnetic resonance (NMR) spectroscopy has been also used for the measurement of the crosslink density using the $T_2$ relaxation time, which is determined by spin-spin relaxation in solid-state NMR. For sulfur-cured rubber vulcanizates, crosslink densities according to the crosslink types of mono-, di-, and polysulfides are measured by treating the rubber samples with a chemical probe composed of thiol and amine compounds. Measurement methods of physical crosslinking by filler, crystallization, and ionic bonding have also been introduced.

• 대한임상독성학회지
• /
• 제16권2호
• /
• pp.68-74
• /
• 2018

Purpose: In 2012, a revised guideline for acute acetaminophen overdose was proposed in the UK, recommending that the treatment threshold should be lowered to 100 mcg/ml at 4 hours after ingestion without risk stratification of hepatotoxicity. However, the poison centers in some developing countries do not have laboratory resources to provide serum drug levels in time. The primary aim of the study is to evaluate the cut-off value of reported dose per kilogram to determine when N-acetylcysteine treatment is warranted under the revised guideline. Methods: Data were collected retrospectively from the toxicology registry of an urban emergency medical center between 1st January 2010 and 30th June 2017. Inclusion criteria were single acute overdose of more than 75 mg/kg in 15 hours from ingestion and over 14 years of age. Subgroups were created by 25 mg/kg increments of reported dose, then sensitivity, specificity, positive predictive value and negative predictive value were calculated for the cut-off values of 100 mg/kg, 125 mg/kg, 150 mg/kg and 175 mg/kg for toxic serum level over '100-treatment line'. Results: A total of 99 patients were enrolled in the study; 24 patients showed toxic serum levels (24.2%). Zero of 17 patients with an ingestion dose under 100 mg/kg showed toxic level (0%), and 0 of 15 under 125 mg/kg (0%), 2 of 14 under 150 mg/kg (14.3%), and 4 of 12 under 175 mg/kg (33.3%) had toxic levels. The higher the ingested dose per kilogram of weight, the higher the frequency of the toxic serum concentration on the first test (${\chi}^2$ test for trend, ${\chi}^2=22.66$, p-value<0.001) and the sensitivity of each value was 100%, 100%, 92% and 76%. Conclusion: In acute single acetaminophen intoxication, the ingestion dose of 100 mg/kg of weight will be useful in determining the need for the N-acetylcysteine antidote in the indigent laboratory environment.

• 대한의료기공학회지
• /
• 제1권1호
• /
• pp.13-59
• /
• 1996

Dep. of Classics &Medical History, College of Oriental Medicint, Kyung Hee University Today, many people are more interested Today, many people are more interested in preventing the disease than curing it. Chi-Kung(氣功) is the way of Life-Cultivation(養生法) peculiar to the orient, it is reported in china that Chi-Kung has an excellent curative value not only in curing the disease but also in preventing it. But the full-scale study of Chi-Kung is not be made up to now in Korea, so I studied the developmental history of chinese Chi-Kung through the oriental medical books. From this study, I reached the following conclusions; 1. Chi-Kung is naturally derived from the self-preservation instinct to adapt oneself to circumstances of the nature, but in the investigation from the documentational records, it is originated in the treatment method of the Sam-Huang-O-Jae(三皇五帝) period to cure the abnormal circulation of the vital force and blood caused by damp(濕). 2. As the principle and the method of the Life-Cultivation of the Chun-Chu-Jeon-Kook(春秋戰國) period were recorded in Huang-Jae-Nai-Gyung(黃帝內經) detailly and the remedy examples by ancient Chi-Kung such as Tao-Yin(導引), Haeng-Chi(行氣) were presented, we considered that theoretical basis of the development of Life-cultivation and Chi-Kung study was furnished in that period. 3. A famous doctor, Hwa-Ta(華引) lived in Han dynasty, researched the theory and practice of Tao-Yin transmitted from the former generations, as that result, he formed a kind of medical, gymnastics what is called O-Keum-Hi(五禽?). It is considered that 'O-Keum-Hi' is a Tao-Yin method developed more practically and systemetically than the Tao-Yin appeared in the 'Jang-Ja'(莊子) or 'Hoy-Nam-Ja'(淮南子). 4. In Wui-Jin-Nambook-Jo(魏曺南北朝) periods, the contents of Chi-Kung were more abundant under the influence of Buddhism(佛敎) and Taoism(道敎). Galhong(葛洪), the author of 'Po-Bak-Ja'(抱朴子) arranged the ancient Chi-Kung method systematically first of all, Tao-Goeng-Gyung, the author of 'Yang-Seong-Yeun-Myung-Rok'(養性延命錄) recorded the 'Yook-Ja-Geul'(六字訣) first time. 5. There is a new development of Chi-Kung therapy in Soo-Tang-Odae(隋唐五代) periods, especially So-Won-Bang(巢元方), the author of 'Jey-Bang-Won-Hwu-Ron' collected almost all of the Chi-Kung method, for curing the disease formed before Soo(隋) period. From that fact, we supposed that Chi-Kung was utilized more widely in curing the disease. 6. 'So-Ju-Cheon-Hwa-Hu-Peob'(小周天火候法) was adopted as the best orthodox approach under the influence of Nae-Tan-Taoist(道敎內丹學波) in Song-Keum-Won(宋金元) periods, especially in the song dynasty, 'Pal-Dan-Geum'(八段錦) was appearde and assignment of six-Chi(六氣) for bowel and viscera in the 'Yook-Ja-Geul'(六字訣) was decided firmly, that is to say Lung-Si(肺-?), Heart-Kha(心-呵), Spleen-Hoa(脾-呼), liver-Hoe(肝-噓), Kidney-chui(賢-吹), Three-Burner-shi(三焦-?). 7. In Myung-Cheong(明淸) periods, The general practitioner applied the principle of 'Byun-Jeng-Ron-Chi(辨證論治) to the Chi-Kung field, and after Myung dynasty the style of doing 'Yook-Ja-Gyel'(六字訣) was developed to the moving style. 8. Today, in china, the study on the Chi-Kyung is being progressed constantly under the positive assistance of government, Chi-Kung-Hak(氣功學) has taking its place as a branch of study step by step. It is considered that the establishment of Chi-Kung-Hak Classroom(氣功學敎室) and Medical Chi-Kung Center(氣功療法室) for special and systematic research are needed, at the same time the settlement of institutional system for training the Chi-Kung technician(氣功師) is also needed.

• 대한한의학원전학회지
• /
• 제4권
• /
• pp.19-73
• /
• 1990

Today, many people are more interested in preventing the disease than curing it. Chi-Kung (氣功) is the way of Life-Cultivation (養生法) peculiar to the orient, it is reported in china that Chi-Kung has an excellent curative value not only in curing the disease but also in preventing it. But the full-scale study of Chi-Kung is not be made up to now in Korea, so I studied the developmental history of chinese Chi-Kung through the oriental medical books. From this study, I reached the following conclusions ; 1. Chi-Kung is naturally derived from the self-preservation instinct to adapt oneself to circumstances of the nature, but in the investigation from the documentational records, it is originated in the treatment method of the Sam-Huang-O-Jae (三皇五帝 )period to cure the abnormal circulation of the vital force and blood caused by damp (濕). 2. As the principle and the method of the Life-Cultivation of the Chun-chu-Jeon-Kook (春秋戰國) periods were recorded in Huang-Jae-Nai-Gyung (黃帝內徑) detailly and the remedy examples by ancient Chi-Kung such as Tao-Yin (導引), Haeng-Chi (行氣) were presented, we considered that theoretical basis of the development of Life-cultivation and Chi-Kung study was furnished in that period. 3. A famous doctor, Hwa-Ta (華陀) lived in Han dynasty, researched the theory and practice of Tao-Yin transmitted from the former generations, as that result, he formed a kind of medical gymnastics what is called O-Keum-Hi (五禽戱). It is considered that 'O-Keum-Hi' is a Tao-Yin method developed more practically and systemetically than the Tao-Yin appeared in the 'Jang-Ja' (莊子) or 'Hoy-Nam-Ja' (淮南子). 4. In Wui-Jin-Nambook Jo (魏晋南北朝) periods, the contents of Chi-Kung were more abundant under the influence of Buddhism (佛敎) and Taoism (道敎). Galhong (葛洪), the author of 'Po-Bak-Ja' (抱朴子) arranged the ancient Chi-Kung method systematically first of all, Tao-Goeng-Gyung (陶宏景), the author of 'Yang-Seong-Yeun-Myung-Rok' (養性延命錄) recorded the 'Yook-Ja-Geul' (六字訣) first time. 5. There is a new development of Chi-Kung therapy in Soo-Tang-Odae (隋唐五代) pefiods, especially So-Won-Bang (巢元方), the author of 'Jey-Byung-Won-Hwu-Ron' (諸病源候論) collected aimost all of the Chi-Kung method, for curing the disease formed before soo (隋) period. From that fact, we supposed that Chi-Kung was utilized more widely in curing the disease. 6. 'So-Ju-Cheon-Hwa-Hu-Peob' (小周天火候法) was adopted as the best orthodox approach under the influence of Nae-Tan-Taoist (道敎內丹學派) in Song-Keum-Won (宋金元) periods, especially in the song dynasty, 'Pal-Dan-Geum' (八段錦) was appeared and assignment of six-Chi (六氣) for bowel and viscera in the 'Yook-Ja-Geul' (六字訣) was decided firmly, that is to say Lung-Si (肺-呬), Heart-Kha (心-呵), Spleen-Hoa (脾-呼), Liver-Hoe (肝-噓), Kidneychui (賢-吹), Three-Burner-shi (三焦-嘻). 7. In Myung-Cheong (明淸) periods, The general practitioner applied the principle of 'Byun-Jeng-Ron-Chi' (辨證論治) to the Chi-Kung field, and after Myeong dynasty the style of doing 'Yook-Ja-Gyel' (六字訣) was developed to the moving style. 8. Today, in china, the study on the Chi-Kung is being progressed constantly under the positive assistance of government, Chi-Kung-Hak (氣功學) has taking its place as a branch of study step by step. It is considered that the establishment of Chi-Kung-Hak Classroom (氣功學教室) and Medical Chi-Kung Center (氣功療法室) for special and systematic research are needed, at the same time the settlement of institutional system for training the Chi-Kung technician (氣功師) is also needed.

• Bulletin of the Korean Chemical Society
• /
• 제34권3호
• /
• pp.753-758
• /
• 2013

Molecular dynamics (MD) simulations have been used to study the diffusion behavior of small gas molecules ($CO_2$) in polyethylene terephthalate (PET)/polylactide (PLA) blends. The Flory-Huggins interaction parameters (${\chi}$) determined from the cohesive energy densities are smaller than the critical value of Flory-Huggins interaction parameters (${\chi}_{critical}$), and that indicates the good compatibility of PET/PLA blends. The diffusion coefficients of $CO_2$ are determined via MD simulations at 298 K. That the order of diffusion coefficients is correlated with the availably fractional free volume (FFV) of $CO_2$ in the PET/PLA blends means that the FFV plays a vital role in the diffusion behavior of $CO_2$ molecules in PET/PLA blends. The slopes of the log (MSD) as a function of log (t) are close to unity over the entire composition range of PET/PLA blends, which confirmes the feasibility of MD approach reaches the normal diffusion regime of $CO_2$ in PET/PLA blends.