• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권2호
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• pp.113-119
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• 1999

The quality of the effluent from an activated sludge aeration tank can deteriorate when the substrate removal rate decreases due to an abrupt reduction in the DO concentration, which is affected by such operating conditions as the loading rate, temperature, wastewater composition, and so on. In this research, a DO control system that includes a PI (proportional-integral) controller/Hiraoka controller was developed and applied to a pilot-scale activated sludge process, then its acceptability was estimated. The applicability of the respiration rate to DO control was also estimated. The respiration rate indicated a variety of input organic loading rates, which is the main disturbance to the DO concentration in an aeration tank. When the influent concentration incrementally decreased and increased between CODcr 1,000 mg/l and 100 mg/l, the control system with a PI controller exhibited a good llperformance-the average DO concentrations were 2.00$\pm$0.14 mg/l and 1.88$\pm$0.15 mg/l (set value was 2.0 mg/l), respectively, and the settling time was just 10 minites. When the control system was operated for 4 days, the DO concentration was 1.99$\pm$0.18 mg/l and 32.6% of the air flowrate was saved. However, the fluctuations in the respiration rates and air flowrates were severe, which could be harmful to the stability of the biomass and mechanical stability of the blower. A possible approach to solve this problem may be the simultaneous control of the loading rate and DO concentration.

• 원예과학기술지
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• 제35권3호
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• pp.300-313
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• 2017

'Unicon' cherry tomato (Solanum lycopersicum) is one of the most highly perishable horticultural crops due to its high water content and respiration rate. This study was carried out to assess the effect of continuous application of $CO_2$ (control [air], 3%, and 5%) on the quality and shelf life of cherry tomato fruits stored at $10^{\circ}C$ and $85{\pm}5%$ relative humidity (RH) at two maturity stages (pink and red). Continuous application of $CO_2$ did not affect the soluble solids content (SSC) or titratable acidity (TA) of the fruit at either maturity stage during storage. However, there was a significant difference among treatments in terms of flesh firmness, cell wall thickness, pectin content, vitamin C content, skin color, lycopene content, weight loss, ethylene production rate, respiration rate, and acetaldehyde and ethanol production. Fruits treated with 5% $CO_2$ maintained their high quality with regards to vitamin C, skin color ($a^*$), lycopene content, weight loss, physiological parameters (ethylene production rate, respiration rate, and volatile compounds), flesh firmness, cell wall thickness, and pectin content at both maturity stages compared with 3% $CO_2$ treatment and the control. Continuous application of $CO_2$ (5%) reduced the ethylene production rate and the production of volatile compounds during storage. Therefore, cherry tomato 'Unicon' fruit can be stored for two weeks without losing fruit quality at both maturity stages under continuous application of 5% $CO_2$ as a postharvest treatment.

• 한국농림기상학회지
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• 제7권3호
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• pp.227-234
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• 2005

From published data of mature forests worldwide, Raich and Nadelhoffer suggested that total belowground carbon allocation (TBCA) could be estimated from the difference between annual rates of soil respiration and aboveground litterfall. Here we analyze new measurements of IRGA-based soil respiration and litterfall of natural mature oak forests dominated by Quercus mongolica in Korea. Rates of in situ soil respiration and aboveground litter production are highly and positively correlated. Our results disagree with the Raich and Nadelhoffer model far world forests. A regression analysis of the data from Q. mongolica forests produced the following relationship: annual soil respiration : 141 + 2.08 ${\times}$ annual litterfall. The least squares regression line has a more gentle slope (2.08) than the slope (2.92) described by Raich and Nedelhoffer for mature forests worldwide. The regression slope of our study indicates that, on average, soil respiration is about two times the aboveground litterfall-C, which further implies that TBCA is similar with annual aboveground litterfall-C at natural Q. mongolica forests in Korea. The non-zero Y-intercept (141) of the regression indicates that TBCA may be greater than litterfall-C where litterfall rate are relativery low. Over a gradient of litterfall-C ranging from 200-370 g C $m^{-2}yr^{-l}$, TBCA increased from 350-530 g C $m^{-2}yr^{-l}$.

• 감성과학
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• 제17권2호
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• pp.85-90
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• 2014

본 연구에서는 업무스트레스 관리를 위해 호흡과 심장박동간의 상관관계를 이용한 최적 호흡법을 유도하고 반복 훈련을 통해 사용자의 건강을 자가 관리하는 시스템을 개발하였다. 일정한 호흡은 심장의 항상성을 유지할 수 있도록 도움을 준다. 심장의 항상성 유지를 통해 업무스트레스 자극으로 인한 심장 리듬의 변화를 빠르게 안정시킬 수 있다. 사람은 개인에 맞는 고유한 호흡리듬을 가지고 있기 때문에, 최적 호흡리듬을 반복적으로 훈련하는 것을 통해 심장의 항상성을 높일 수 있다. 본 시스템은 개인에 맞는 최적 호흡리듬을 찾아서 이를 반복적으로 훈련할 수 있는 시스템을 개발하였다. 그리고 업무스트레스가 높은 콜센터 직원들을 대상으로 검증실험을 실시하였다. 검증실험 결과 자신의 맞는 호흡주기를 사용하여 호흡을 하면 심장의 반응이 안정성을 보이고 부교감이 활성화 되는 것을 확인할 있었다. 개발한 시스템을 활용하면 감정노동자들 중에서 콜센터 상담 업무스트레스를 저감시킬 수 있을 뿐만 아니라, 이를 통한 업무효율증가와 개인의 건강관리에도 많은 도움을 줄 수 있을 것으로 예상된다.

• 지역사회간호학회지
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• 제12권3호
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• pp.773-784
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• 2001

The study was conducted to test the effectiveness of thermotherapy for high school girls who suffered from disruption in school activities through dysmenorrhea, and to study the extent of its availability in school infirmaries as one of the nursing methods. The test for the study was designed to make a contrast between half of the subjects (20) who did not receive the thermotherapy, and the rest (20) who did during the period from February 15th to April 14th, 2001. Measurements were taken of the subjects who complained of painful menstruation by a set of variables. The variables that were established and complemented by Hur, Mung-heang (1985) consist of 29 items that assess the dysmenorrhea and vitality through the symptoms of primary menstruation visually. Spsswin was used to analyze the data. The Cronbach-${\alpha}$ method was used for statistic confidence, and the test effect of both the subjects and the contrary ones was analyzed by way of T-test. The conclusions are as follow. (1) The hypothesis 1 states that the subjects with themotherapy have a lower degree of dysmenorrhea rather than the contrary ones without it. By the above assessment, there was a quantitative difference between the subjects at 39.40, and the contrary ones at 22.0. After the themotherapy, the degree of dysmenorrhea in the subjects was low indicating that there is a still 5% chance of statistic meaningful difference (t= 2.651. P= .012). As a result, the first hypothesis was accepted. (2) The hypothesis 2 states that the subjects with themotherapy have a different primary menstruation than those without. Data indicate that there was a difference of -5.95 and -4.80. The subjects showed low degrees. Since it was statistically insignificant (t=-1.398, P=.170), the second hypothesis was rejected. (3) The hypothesis 3 states that the subjects with themotherapy have a different vitality. The vitality was measured in three aspects. (1) pulse rate (/min) The hypothesis 3' states that the subjects with themotherapy have the different pulse rate from those without. Data indicate that there was no statistically meaningful difference between the two groups (t=.237, P=. 814). Therefore, the third 1st hypothesis was rejected. (2) Respiration rate The hypothesis 3' states that the subjects with themotherapy have a different respiration rate between pre-thermotherapy and post-thermotherapy. in contrast with the ones without it. The data show that there was no statistically meaningful difference (t=.133. P=.895). A little respiration rate difference was shown between pre-and post-. Likewise. the third 2nd hypothesis was rejected. (3) Blood pressure In the 3rd sub-hypothesis that there would be a difference between experimental and controlled groups was also rejected. because there was no statistically significant difference between the contracting blood pressure and the relaxing blood pressure. In terms of vitality. the pulse rate, respiration rate and blood pressure have no statistical meaning but the first two ones show the decreasing in the rate. In short, though exclusive studies focused on thermo therapy have not been conducted and the comparison can not be made, this study shows not only that the thermotherapy is very effective to dysmenorrhea, but also that it can be available in school infirmaries as one of the nursing methods.

• 한국식물병리학회지
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• 제11권1호
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• pp.61-65
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• 1995

Photosynthetic characteristics of soybean leaves infected with Pseudomonas syringae pv. glycinea were investigated for 8 days. The difference in photosynthesis rate between healthy and diseased soybean leaves decreased for 2 to 4 days after inoculation and then increased. In respiration rate, healthy and diseased leaves showed the same tendency as photosynthetic rate. The stomatal resistance increased following Pseudomonas syringae pv. glycinea infection. The total chlorophyll content of the infected leaf was less than that of the uninfected. Pseudomonas syringae pv. glycinea infection induced the malformation of stacked grana in chloroplast. Dry matter production declined after infection.

• 생명과학회지
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• 제20권7호
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• pp.1127-1133
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• 2010

총광합성율의 변이는 순광합성율에 호흡율을 더해서 구한 것으로 계통간의 변이는 순광합성율과 대동소이하였으며 rosetteness는 초장, 초고 그리고 상대엽면적(SLA)과는 고도로 유의한 정의 상관을 보여 초장 및 초고가 클수록 잎의 부착밀도가 낮고 잎이 엷은 것으로 나타났다. 식물의 지상부 생장량은 호흡율에 의해 보다 크게 영향을 받는 것으로 나타났는데 이는 호흡이 잎 뿐 아니라 줄기에서도 일어나는데 기인한 것으로 사료된다. 그리고 엽의 부착밀도가 낮은 계통들이 지상부 생육이 좋았는데, 이것은 광합성율을 높이기 위해서는 상대엽면적(SLA)이 큰 즉, 엽의 두께가 얇은 계통을 선발하는 것이 유리함을 말해 준다.

• 대한의용생체공학회:의공학회지
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• 제10권3호
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• pp.309-316
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• 1989

In this paper, the patient monitor consisting of amplifier, scan converter, A/D converter, CRT amplifier, and micro-controller part was developed. This patient monitor measures the patient's 4 states in the hospital such as electro-cardiography, respiration, blood pressure, and temperature. The control and processing methods based on micro-processor employ the flexibility, extensibility and economy over other conventional system. The followings are incorporated in this system. First, record the heart rate trends for 1 and 4 hours respectively. Second, measures the respiration by impedance pneumography. Third, measures the blood pressure with auto-zero balance. Fourth, linesrize the temperatures by bridge method.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.423-432
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• 1993

The changes of quality of Fresh Shiitake (Lentinus edodes) was studied in this research work by investigating the effect of low $O_2$ content and high $CO_2$ content, well known as CA Treatment in storage, on the respiration rate and PPO Activity that was the main factor in Shiitake quality decay. CA Condition was conducted in 3 research periods that combined the $O_2$content(1%, 5% and 10%) and $CO_2$ content (5%, 10%, 15% and 20%) and air treatment as the control. The lower $O_2$content was the lower respiration rte that was showed in combination the lower respiration rate that was showed in combination of 20% $CO_2$ and 1% $O_2$ (the lowest), and the control air treatment was the highest . Very low $O_2$ content, conversly, did not show a satisfying result to the product.

• 대한인간공학회지
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• 제4권2호
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• pp.17-24
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• 1985

To compare heart rate, $O_2$ uptake, $Vo_2$ ($O_2$ consumption), blood pressure (systolic, diastolic), reaction time, stability, flicker fusion value during 4 load levels with Rs (self-paced respiration) and Rp (paced respiration), 4 subjects participated in this experiment 1 hour/day, 6 days/week for 9 weeks. The cycle of Rp is 6 sec. (inspiration: 3 sec. & expiration: 3 sec.) Implications of the results are discussed in terms of the change in the physiological responses and human performance by the respiratory pattern. The results are as follows, 1. The changing magnitude of heart rate with Rp was larger than with Rs and the variance during load level 4 was significant. 2. The $Vo_2$ with Rp was smaller than with Rs and maximal $O_2$ uptake given load levels with Rp occurred and for two subjects, it significantly moved from low load level to high load level. 3. The changing magnitude of blood pressure was not consistent but the systolic pressure with Rp was smaller at rest than with Rs. 4. The score of reaction time test and stability test with Rp was better than with Rs.