• 한국세라믹학회지
• /
• 제32권6호
• /
• pp.726-734
• /
• 1995

Pb(Zr0.53Ti0.47)O3 (PZT) ceramics having different microstructures were fabricated at low temperatures using calcined PZT powders with addition of excess PbO powder and/or ball milling. The effects of excess PbO and ball milling time on the microstructure, the sintering characteristic, and the mechanical properties of these ceramics were studied. Fine powders with average particle size of 0.38㎛ could be obtained by ball milling with 2.5 mm Ф zirconia balls for 120 hours. By the addition of 2mol% of excess PbO to these powders, it was possible to obtain well-densitified PZT ceramics at low sintering temperature of 980℃. Densification behavior of PZT was affected by the addition of excess PbO powder, while, grain growth was hardly affected by PbO addition. It was observed that Vicker's hardness decreased and fracture toughness increased with the increasing amount of PbO. At 1mol% excess PbO, it was shown that the minimum values of hardness and maximum fracture toughness were achieved. In addition, with increasing sintering time, the fracture toughness decreased and the hardness increased.

• Environmental Engineering Research
• /
• 제13권3호
• /
• pp.112-118
• /
• 2008

Residual solid in excess sludge treated by hydrothermal reaction was investigated as raw material for its recycling. Treated excess sludge and residual solid were also focused on their content change during hydrothermal reaction. Two kinds of excess sludge, obtained from a local food factory and a municipal wastewater treatment process, were tested under various conditions. Following hydrothermal reaction, depending on the reaction conditions, biodegradable substrates in treated excess sludge appeared to increase. The separated residual solid was a composite composed of organic and inorganic materials. The proportion of carbon varied from 34.0 to 41.6% depending on reaction conditions. Although 1.89% of hazardous materials were detected, SiO2 (Quartz) was a predominant constituent of the residual solid. X-ray diffraction (XRD) experiments revealed that the residual solid was of a partially amorphous state, suggesting that the residual solids could be easily converted to stable and non harmful substances through a stabilization process. Thus, this technology could be successfully used to control excess sludge and its reuse.

• Nuclear Engineering and Technology
• /
• 제54권8호
• /
• pp.2883-2897
• /
• 2022

According to the Renewable Energy 3020 Implementation Plan announced in 2017 by the South Korean government, the electricity share of renewable energy will be expanded to 20% of the total electricity generation by 2030. Given the intermittency of electricity generation from renewable energy, realization of such a plan presents challenges to managing South Korea's isolated national electric grid and implies potentially large excess electricity generation in certain situations. The purpose of this study is: 1) to develop a model to accurately simulate the effects of excess electricity generation from renewables which would arise during the transition, and 2) to propose strategies to manage excess electricity generation through effective utilization of domestic electricity generating capabilities. Our results show that in periods of greater PV and wind power, namely the spring and fall seasons, the frequency of excess electricity generation increases, while electricity demand decreases. This being the case, flexible operation of coal and nuclear power plants along with LNG and pumped-storage hydroelectricity can be used to counterbalance the excess electricity generation from renewables. In addition, nuclear energy plays an important role in reducing CO₂ emissions and electricity costs unlike the fossil fuel-based generation sources outlined in the 8th Basic Plan.

• 사상체질의학회지
• /
• 제18권2호
• /
• pp.1-14
• /
• 2006

1. Objectives This study is purposed to classify deficiency syndrome(虛證) and Excess syndrome(實證) of chief lung-disorder diseases. 2. Methods It was researched on the comparative and literal study about the relation to Yeong-Chu Gyeong-maek Chapter (${\ulcorner}$靈樞 經脈編${\Ircorner}$) and Dongui-Bogam (${\ulcorner}$東醫寶鑑${\Ircorner}$) and Dongui-Susebowon (${\ulcorner}$東醫壽世保元${\Ircorner}$) in chief lung-disorder symptoms or diseases. 3. Results and Conclusions (1) The chief lung-disorder diseases of Yeong-Chu Gyeong-maek Chapter (${\ulcorner}$靈樞 經脈編${\Ircorner}$), Dongui-Bogam (${\ulcorner}$東醫寶鑑${\Ircorner}$) and Dongui-Susebowon (${\ulcorner}$東醫壽世保元${\Ircorner}$) are asthma(喘), coughing(咳), fullness in the chest(胸滿), sweating symptoms(汗出), cold-heat symptoms(寒熱), dysphoria(煩躁) and sneezing. (2) Asthma symptom(喘) was shown to Soeumin's 4 exterior deficiency diseases, Taeumin's 1 exterior deficiency disease and 1 interior excess disease, and Soyangin's 1 interior excess disease. (3) Coughing symptom(咳) was shown to Soeumin's 1 extrerior deficiency disease and Taeumin's 1 interior excess disease. (4) Fullness in the chest(胸滿) was shown co Soyangin's 4 exterior excess diseases. (5) Sweating symptoms(汗出) was shown to Soeumin's 10 exterior deficiency diseases, Taeumins's 1 exterior deficiency disease, and Soyangin's 1 exterior defecieny disease. (6) Cold-heat symptoms(寒熱) was shown to Soyangin's 4 exterior excess diseases. (7) Dysphoria(煩躁) was shown co Soeumin's 1 exterior deficiency disease and 8 interior deficiency diseases, Taeumin's 1 interior excess disease, and Soyangin's 4 exterior excess and interior excess diseases. (8) Sneezing symptom was shown to Taeumin's 1 exterior excess disease.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.308-308
• /
• 2017

The low and unstable yield of soybean has been a major problem in Japan. Excess soil moisture conditions are one of the major factors to restrict soybean productivity. More than 80 % of soybean crops are cultivated in converted paddy fields which often have poor drainage. In central and eastern regions of Japan, the early vegetative growth of soybean tends to be restricted by the flooding damage because the early growth period is overlapped with the rainy season. Field observation shows that induced excess water stress in early vegetative stage reduces dry matter production by decreasing intercepted radiation by leaf and radiation use efficiency (RUE) (Bajgain et al., 2015). Therefore, it is necessary to evaluate the responses of soybean growth for excess water conditions to assess these effects on soybean productions. In this study, we aim to modify the soybean crop model (Sinclair et al., 2003) by adding the components of the restriction of leaf area development and RUE for adaptable to excess water conditions. This model was consist of five components, phenological model, leaf area development model, dry matter production model, plant nitrogen model and soil water balance model. The model structures and parameters were estimated from the data obtained from the field experiment in Tsukuba. The excess water effects on the leaf area development were modeled with consideration of decrease of blanch emergence and individual leaf expansion as a function of temperature and ground water level from pot experiments. The nitrogen fixation and nitrogen absorption from soil were assumed to be inhibited by excess water stress and the RUE was assumed to be decreasing according to the decline of leaf nitrogen concentration. The results of the modified model were better agreement with the field observations of the induced excess water stress in paddy field. By coupling the crop model and the ground water level model, it may be possible to assess the impact of excess water conditions for soybean production quantitatively.

• 환경위생공학
• /
• 제11권3호
• /
• pp.53-61
• /
• 1996

The subject of this study was to analyse overviews of companies which exceed TLV by industry, hazardous factors, and to estimate the numbers of companies measured in 1993 and the implementation rate of working environment measurement by the act of industrial safety and health The result of this study was as follow. 1. The number of cases which exceed TLV was 5,937 companies. In distribution of excess companies by the scale of workers, small scale cases under the 49 workers were 3,150 companies(53.0%) of total cases, medium scale cases between 50 - 299 workers were 2,248 companies(37.9%), and large scale cases over 300 workers were 539 companies(9.1%). By the industry of excess companies, it was marked high rate in manufacture of fabricared metal products(except machinary and equipment), manufacture of textiles of each 1,048 companies(17.7%), and 1,018 companies(17.1%). By the area of excess companies, it was shown high rate in Kyeongki area marked 1,679 companies(28.3%) and Daegu-Kyeongbuk area were marked 1,417 companies (23.9%). By the hazardous factors of excess companies, noise was recorded high rate in 5,160 companies (86.9%), dust was shown in 1,245 companies(21.0%), organic solvent was marked 130 companies(7.9%). The number of excess factors by the company was 1.2. In this result, the more it was bigger scale companies, the more excess factors were much more and the more it was recorded higher rate in noise organic solvent heavy metals, etc. 2. The measured cases in institutes during 1994 were 1,596 companies, and excess cases were 157 companies(9.8%) among them. By the scale of workers, small scale cases under the 49 workers were 190 companies (17.9%) among 1,064 companies, cases of medium scale cases between 50-299 workers were 127 companies (27.9%) among 463 companies, and large scale cases over 300 workers were 31 companies(44.9%) among 69 companies. In this result industry of the highest rate shown was manufacture of basic metals in 20 companies exceeded among 53 companies (37.7%), and was manufacture of pulp, paper production in 14 companies exceeded among 40 companies(35.0%), and the excess rate were high in bigger scale. 3. Companies estimated by the data of excess cases and excess rate in 1993 were 30,474 implementation rate estimated for measurement of working environment was 34.3% of companies in korean industry. In this result, it was comparatively shown of measurement rate for the working environment in manufacture of pulp, paper product, manufacture of machinary and equipment n.e.c., and of high measurement rate and excess rate in manufacture of electrial machinary and apparatus, and manufacture of basic metals.

• 동의생리병리학회지
• /
• 제32권3호
• /
• pp.171-177
• /
• 2018

The purpose of this study was to evaluate the reliability and the validity of Deficiency and Excess Pattern Identification Questionnaire. The number of subjects enrolled in this study was 248, from July 2015 to March. 2016. The surveys was conducted two times with 3 month interval. The Cronbach's ${\alpha}$ analysis for internal reliability, Pearson Correlation Coefficient analysis for test-retest reliability were conducted. Factor analysis with varimax rotation for construct validity was used. Kappa analysis for diagnostic reliability were used. The significant p-value was < .05. The Cronbach's ${\alpha}$ was .929 in Deficiency and .932 in Excess questionnaire. The reliabilities between test and retest Intra Correlation Coefficient (ICC) was .71-.762 in the Deficiency, and .58-.786 in Excess questionnaire, respectively. Deficiency was divided by five factors, and Excess four factors. The factor convergence was 72.54% in the Deficiency and 67.5% in Excess questionnaire. The test-retest agreement of four pattern was 68.5% and Kappa was .530. This study reveals that Deficiency and Excess Pattern Identification Questionnaire is a reliable and valid. However, further study to validate the questionnaire is needed.

• 대한한방내과학회지
• /
• 제35권1호
• /
• pp.50-58
• /
• 2014

Objectives : The aim of this study was to analyze relationship between post-stroke depression (PSD) and cold, heat, deficiency and excess patterns. Methods : Twenty-eight PSD patients were recruited from STROKE center and measured with questionnaires for cold, heat, deficiency and excess patternvalues and saliva for cortisol awakening response (CAR). Saliva samples were collected immediately, 15, 30 and 45 min after awakening. In addition, Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HDRS) were conducted for PSD severity. We conducted correlation analysis to find the relationship between cold, heat, deficiency and excess patterns and CAR or BDI and HDRS. Results : Deficiency and excess patterns werepositively correlated with area under the curve with respect to the increase (AUCi), but not with area under the curve with respect to the global (AUCg), in CAR. Furthermore, it was negatively correlated with BDI and HDRS, while cold and heat patterns were not correlated with CAR, BDI and HDRS. Conclusions : In terms of deficiency and excess patterns, the higher the PSD severity, the higher the deficiency and the lower the PSD severity, the higher the excess. However, there was not a significant relationship between PSD and cold and heat patterns.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2004년도 춘계학술발표회
• /
• pp.714-721
• /
• 2004

The purpose of this study is to find out the similitude laws for dissipation velocity of excess pore pressure after liquefaction according to magnitude of input accelerations and height of model soils from the results of impulse load tests. In impulse load tests, model soils were constructed to the height of 25cm, 50cm, and 100cm in acrylic tubes whose inside diameters were 19cm and 38cm respectively, and impulse loads were applied at the bottom of each model soil to liquefy the entire model soil. Excess pore pressure distribution by depth and settlement of soil surface were measured in each test. Dissipation curves of excess pore pressure measured in each tests were simulated by solidification theory, and dissipation velocities of excess pore pressure were determined from the slope of simulated dissipation curves. From the results of impulse load tests, dissipation velocity of excess pore pressure was not affected by magnitude of input acceleration, and from this fact, dissipation process was proved to be different from dynamic phenomenon. However, dissipation velocity of excess pore pressure increased as height of model soil increased and showed little difference as diameter of model soil increased. Therefore, the similitude law for dissipation velocity could be expressed by the similitude law for model height to 0.2 without regard to the diameter of model soil.

• 한국응용과학기술학회지
• /
• 제35권2호
• /
• pp.472-477
• /
• 2018

전신마취제의 잉여 몰부피는 Halobacteriun Halobium에서 추출분리된 Purple membrane과 Red membrane에서 vesicle의 현탁액에서 $25^{\circ}C$ 잉여부피 dilatometer로 측정되었다. 우리의 연구에 의해 전신마취제인 Propofol은 잉여몰부피와 상관 관계가 있는 것으로 밝혔다. Halobacteriun Halobium에서 비중 차이에 의해 추출 분리된 Purple membrane과 Red membrane의 잉여몰 부피는 vesicle의 아미노산과 지질의 영향이다. 이들은 잉여 몰부피 dilatometer로 잉여 몰 부피를 측정되었으며, 흡광세기는 280 nm 330 nm 에서 연구되었다. Purple membrane과 Red membrane이 Propofol에 의한 입자크기 분석, 상대적 혼탁도가 기계적 특성을 위해 연구되었다. 확산 교환에 의한 점성 중합체 용액의 입자 크기 분석은 측정에 의한 중요한 단계이다. Propofol이 vesicle에서 재구성된 시료들 중에서, 특히 PM+RM+Propofol의 잉여 몰 부피가 PM, RM의 잉여 몰 부피보다 가장 크게 측정되었다.