• Title/Summary/Keyword: internal stability

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A Basic Study on Feasibility Analysis for Solar Energy Facility using Standard Broiler House Roof (표준육계사의 지붕을 활용한 태양에너지 설비 타당성 분석에 관한 기초 연구)

  • Kim, Jin-Hyun;Jung, Sung-Jin;Kim, Tae-Wook;Choi, Jun-Hak;Ha, Yu-Shin
    • Journal of the Korean Solar Energy Society
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    • v.34 no.4
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    • pp.57-65
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    • 2014
  • In order to reduce greenhouse gas emissions in recent agricultural energy and increase the energy self-sufficiency rate of each farmer, it is extremely important to expand the supply of solar energy using unused space of agricultural facilities, roof. This study surveyed and analyzed the environmental and administrative factors such as problems according to the structure, azimuth and latitude of broiler houses and stability of standard broiler houses required to use broiler house roof based on the poultry houses in Sangju-si. The results can be summarized as follows: 55.6% of the solar energy facilities of according to the classification of arable lands of broiler houses were available, and 31.7% of them were available by classifying according to the azimuth. However, 20.6% of them were available in the survey considering all the arable land and azimuth. In the roof inclination of the broiler houses, from 20 to $25^{\circ}$ was the most common, 30 broiler houses. The broiler houses with the roof inclination more than $20^{\circ}$ accounted for 63% of the total. It was considered that the inclination was generally proper. In the structural safety, only 3 broiler houses that were constructed as a standard broiler house were available. In practice, all but one broiler house was inappropriate to expand the solar energy project using roof. The solar thermal facility weighed $63.6kg/m^2$ in total: the frame and solar thermal collector weighed $27.8kg/m^2$ and $35.8kg/m^2$, respectively. The standard broiler house required to be internally reinforced. This study suggested a plan for internal reinforcement and a feasible plan because there were problems with structural safety when installing solar thermal and photovoltaic systems.

TREATMENT OF OPENBITE WITH MYOFUNCTIONAL THERAPY IN MOYAMOYA DISEASE PATIENT (근기능요법을 통한 모야모야병 환자의 개방 교합 치료)

  • Lee, Chang Keun;Lee, Dae Woo;Kim, Jae Gon;Yang, Yeon Mi
    • The Journal of Korea Assosiation for Disability and Oral Health
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    • v.13 no.1
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    • pp.19-22
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    • 2017
  • Moyamoya disease is characterized by progressive bilateral narrowing of the internal carotid arteries(ICA) and their main branches, and formation of a fine vascular network (moyamoya vessels) at the base of brain. Mild intellectual or motor impairment, or both can be seen in moyamoya disease patient. Patients having intellectual disability usually have malocclusions associated with oral habits such as tongue thrusting, bruxism, or clenching. A patient with moyamoya disease and cerebral palsy visited Chonbuk National University hospital for dental examination. She showed mild openbite on anterior teeth, and had oral habits such as mouth breathing, tongue thrusting, and drooling. She was treated with myofunctional therapy(MFT) whose purpose was to strengthen orofacial muscles. Lip closing force and bite force were recorded to evaluate the muscle tone. Tongue crib was delivered to restrict tongue thrusting habit, since her compliance to the MFT was decreased after 6 months of treatment. With the MFT and tongue crib, the openbite was fairly improved. When myofunctional therapy has difficulty in obtaining good compliances, the treatment should not be effective enough. Although intellectually disabled patients are not compliant enough, thus a habit breaking device should be needed to treat the openbite caused by oral habits, dentist should make an effort to do MFT, since it could reduce a treatment period, and enhance the stability.

Sleep-Related Respiratory Disturbances (수면과 관련된 호흡장애)

  • Moon, Hwa-Sik
    • Sleep Medicine and Psychophysiology
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    • v.2 no.1
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    • pp.55-64
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    • 1995
  • During sleep, relatively major respiratory physiological changes occur in healthy subjects. The contributions and interactions of voluntary and metabolic breathing control systems during waking and sleep are quite different Alterations of ventilatory control occur in chemosensitivity, response to mechanical loads, and stability of ventilation. The activities of intercostal muscles and muscles involved in regulating upper airway size are decreased during sleep. These respiratory physiological changes during sleep compromise the nocturnal ventilatory function, and sleep is an important physiological cause of the nocturnal alveolar hypoventilation. There are several causes of chronic alveolar hypoventilation including cardiopulmonary, neuromuscular diseases. Obstructive sleep apnea syndrome (OSAS) is an important cause of nocturnal hypoventilation and hypoxia. Coexistent cardiopulmonary or neuromuscular disease in patients with OSAS contributes to the development of diurnal alveolar hypoventilation, diurnal hypoxia and hypercapnia. The existing data indicates that nocturnal recurrent hypoxia and fragmentation of sleep in patients with OSAS contributes to the development of systemic hypertension and cardiac bradytachyarrhythmia, and diurnal pulmonary hypertension and cor pulmonale in patients with OSAS is usually present in patients with coexisting cardiac or pulmonary disease. Recent studies reported that untreated patients with OSAS had high long-term mortality rates, cardiovascular complications of OSAS had a major effect on mortality, and effective management of OSAS significantly decreased mortality.

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A study on the effect of support structure of steel rib in partitioning excavation of tunnel (터널 상·하반 분할 굴착 시 강지보재 지지구조 효과에 대한 연구)

  • Kim, Ki-Hyun;Kim, Yeon-Deok;Hwang, Beoung-Hyeon;Choi, Yong-Kyu;Kim, Sang-Hwan
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.5
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    • pp.543-561
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    • 2020
  • This paper is the result of the study on the effect of the support structure of the tunnel steel rib. In tunnel excavation, the top and bottom half excavation methods result in subsidence of steel rib reinforcement due to insufficient support of steel rib reinforcement when the ground is poor after excavation. The foundation of the steel rib installed in the upper half excavates the bottom part of the base, causing the subsidence to occur due to various effects such as internal load and lateral pressure. As a result, the tunnel is difficult to maintain and its safety is problematic. To solve these problems, steel rib support structures have been developed. For the purpose of verification, the behavior of the supporting structure is verified by model experiments reduced to shotcrete and steel rib material similarity, the numerical analysis of ΔP and ΔP generated by bottom excavation by Terzaghi theoretical equation. As a result, it was found that the support structure of 20.100~198.423 kN is required for the 10~40 m section of the depth for each soil of weathered soil~soft rock. In addition, as a result of the reduced model experiment, a fixed level of 50% steel rib deposit of steel rib support structure was installed. The study shows that the installation of steel rib support structures will compensate for uncertainties and various problems during construction. It is also thought that the installation of steel rib support structure will have many effects such as stability, economy, and air reduction.

The Effects of Middle School Students' Participation in After-school Sports Activities on Psychological Well-being (중학생의 방과 후 스포츠 활동 참여가 심리적 안녕감에 미치는 영향)

  • Kim, Ki Seung;Ham, Hae-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.3
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    • pp.469-480
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    • 2020
  • The purpose of this study is to empirically analyze the effects of middle school students' participation in after-school sports on psychological well-being. A survey was conducted on 280 students in 7th, 8th, and 9th grades attending two middle schools in Gongju-si, Chungnam, for one month from September 8 to October 17, 2019. The scale developed by Ryff (1995) was used to measure psychological stability. Subfactors including self-acceptance (6 questions), positive interpersonal relationships (5 questions), autonomy (6 questions), environmental control (5 questions), purpose of life (5 questions), and personal growth (5 questions) comprised a total of 32 questions measured on the Likert 5-point scale. The internal fit score (Cronbach's alpha) was .76-.83, with 146 students (52.1%) participating in after-school sports activities. The effect was high in the participant group. All variables, including the six subfactors, were verified statistically. These findings are consistent with the studies of Kang Myung-hwa (2011) and Kim Pan-su (2012), which reported that the sports activities of middle school students directly affect the development of emotions. This study verified the need to strengthen after-school sports activities and to engage problem children. After-school sports activities should be reviewed in the context of social issues that are becoming increasingly serious.

Development and Validation of an HPLC Method for the Pharmacokinetic Study of Dipyridamole in Human (디피리다몰 체내동태 연구를 위한 혈청 중 디피리다몰의 HPLC 정량법 개발 및 검증)

  • Cho, Hea-Young;Kang, Hyun-Ah;Moon, Jae-Dong;Choi, Hoo-Kyun;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.36 no.1
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    • pp.45-51
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    • 2006
  • A rapid, selective and sensitive reversed-phase HPLC method for the determination of dipyridamole in human serum was developed, validated, and applied to the pharmacokinetic study of dipyridamole. Dipyridamole and internal standard, loxapine, were extracted from human serum by liquid-liquid extraction with diethyl ether and analyzed on a Nova Pak $C_{I8}$ column with the mobile phase of 40 mM ammonium acetate:methanol:acetonitrile (35:35:30)(v/v/v, pH 7.8). Detection wavelength of 280 nm and flow rate of 1.0 mL/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^3$ factorial design using a fixed dipyridamole concentration (50 ng/mL) with respect to its peak area and retention time. And also, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of 2-2000 ng/mL with correlation coefficients greater than 0.999. The lower limit of quantification using 0.5 mL of serum was 2 ng/mL, which was sensitive enough for pharmacokinetic studies of dipyridamole. The overall accuracy of the quality control samples ranged from 103.94 to 105.86% for dipyridamole with overall precision (% C.V.) being 4.60-11.49%. The relative mean recovery of dipyridamole for human serum was 97.64%. Stability studies showed that dipyridamole was stable during storage, or during the assay procedure in human serum. The peak area and retention time of dipyridamole were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of dipyridamole in human serum samples for the pharmacokinetic studies of orally administered Dimor tablet (75 mg as dipyridamole) at three different laboratories, demonstrating the suitability of the method.

Development and Validation of HPLC Method for Pharmacokinetic Study of Promethazine in Human (염산프로메타진 체내동태 연구를 위한 혈청 중 프로메타진의 HPLC 정량법 개발 및 검증)

  • Cho, Hae-Young;Kang, Hyun-Ah;Lee, Hwa-Jeong;Choi, Hoo-Kyun;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.36 no.1
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    • pp.23-29
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    • 2006
  • A rapid, selective and sensitive reversed-phase HPLC method for the determination of promethazine in human serum was developed, validated, and applied to the pharmacokinetic study of promethazine. Promethazine and internal standard, chlorpromazine, were extracted from human serum by liquid-liquid extraction with n-hexane containing 0.8% isopropanol and analyzed on a Capcell Pak CN column with the mobile phase of acetonitrile-0.2 M potassium dihydrogen phosphate (42:58, v/v, adjusted to pH 6.0 with 1 M NaOH). Detection wavelength of 251 nm and flow rate of 0.9 mL/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^{3}$ factorial design using a fixed promethazine concentration (10 ng/mL) with respect to its peak area and retention time. In addition, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of 1-40 ng/mL with correlation coefficients greater than 0.999. The lower limit of quantification using 1 mL of serum was 1 ng/mL, which was sensitive enough for pharmacokinetic studies. The overall accuracy of the quality control samples ranged from 96.15 to 105.40% for promethazine with overall precision (% C.V.) being 6.70-11.22%. The relative mean recovery of promethazine for human serum was 63.54%. Stability (freeze-thaw and short-term) studies showed that promethazine was stable during storage, or during the assay procedure in human serum. However, the storage at $-80^{\circ}C$ for 4 weeks showed that promethazine was not stable. Extracted serum sample and stock solution were not allowed to stand at ambient temperature for 12 hr prior to injection. The peak area and retention time of promethazine were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of promethazine in human serum samples for the pharmacokinetic studies of orally administered Himazin tablet (25 mg as promethazine hydrochloride) at three different laboratories, demonstrating the suitability of the method.

Evaluation of the Probability of Failure in Rock Slope Using Fuzzy Reliability Analysis (퍼지신뢰도(fuzzy reliability) 해석기법을 이용한 암반사면의 파괴확률 산정)

  • Park, Hyuck-Jin
    • Economic and Environmental Geology
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    • v.41 no.6
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    • pp.763-771
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    • 2008
  • Uncertainties are pervasive in engineering geological problems. Therefore, the presence of uncertainties and their significance in analysis and design of slopes have been recognized. Since the uncertainties cannot be taken into account by the conventional deterministic approaches in slope stability analysis, the probabilistic analysis has been considered as the primary tool for representing uncertainties in mathematical models. However, some uncertainties are caused by incomplete information due to lack of information, and those uncertainties cannot be handled appropriately by the probabilistic approach. For those uncertainties, the theory of fuzzy sets is more appropriate. Therefore, in this study, fuzzy reliability analysis has been proposed in order to deal with the uncertainties which cannot be quantified in the probabilistic analysis due to the limited information. For the practical example, a slope is selected in this study and both the probabilistic analysis and the fuzzy reliability analysis have been carried out for planar failure. In the fuzzy reliability analysis, the dip angle and internal friction angle of discontinuity are considered as triangular fuzzy numbers since the random properties of the variables cannot be obtained completely under the conditions of limited information. In the study, the fuzzy reliability index and the probabilities of failure are evaluated from fuzzy arithmetic and compared to those from the probabilistic approach using Monte Carlo simulation and point estimate method. The analysis results show that the fuzzy reliability analysis is more appropriate for the condition that the uncertainties arise due to incomplete information.

Bibliographic Study on Pediatric Chuna(推拿) in the Myung.Chung(明淸) Dynasties (명청시기(明淸時期) 소아추나(小兒推拿)에 관(關)한 문헌적(文獻的) 고찰(考察))

  • Ding Guo-Xun;Lee Song-Shil;Baek Jin-Woong;Lee Sang-Jae;Kim Kwang-Ho
    • Journal of Society of Preventive Korean Medicine
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    • v.8 no.2
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    • pp.31-44
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    • 2004
  • Bibliographic study on pediatric Chuna in the Myung Chung dynasties resulted as the following. 1. Pediatric Chuna experts in Myung dynasty utilized methods of Chuna to a great extense as means of preventing and treating various kinds of pediatric disorders. 2. Pediatric Chuna experts in Myung dynasty put emphasis on diagnosis through the doctor's inspection. 3. Pediatric Chuna experts in Myung dynasty developed and applied special acupoints for pediatric Chuna. 4. Pediatric Chuna experts in Myung dynasty put emphasis on replenishing and discharging according to hand manipulation. 5. Pediatric Chuna experts in Myung dynasty developed and applied methods of massaging with herbal medicine. 6. Pediatric Chuna experts in Myung dynasty put methods of Chuna into songs for handier use. 7. Pediatric Chuna experts in Chung dynasty corrected the errors of the predecessors and further developed the handed down advantages. 8. Pediatric Chuna experts in Chung dynasty specifically combined the theories of Chuna with characteristics of pediatric physiology. 9. Pediatric Chuna experts in Chung dynasty described treatments by symptoms systematically. 10. Pediatric Chuna experts in Chung dynasty, criticizing the trend at the time of despising pediatric Chuna, endeavored to spread pediatric Chuna. 11. Pediatric Chuna experts in Chung dynasty arranged the relationship between hand manipulation of Chuna and herbal medicine. 12. Pediatric Chuna experts in Chung dynasty arranged various kinds of methods for diagnosis, including diagnosis by palpation of the chest and the abdomen. 13. Pediatric Chuna experts in Chung dynasty combined the method of multiple hand manipulation and method of basic hand manipulation. 14. The theories of pediatric Chuna before Myung Chung dynasties only put emphasis on Ki and Blood, not combining with the basic principles of Korean medicine like Eum/Yang and Five Phases. The scholars of Myung Chung dynasties came to successfully combine the principles of Korean medicine like stability theory, Jang and Bu (internal organs) theory, and Eum-Yang theory with the theories of pediatric Chuna. This combination best characterizes the theories of pediatric Chuna in the Myung Chung dynasties.

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Detection of Irradiated Chicken, Pork and Beef by ESR Spectroscopy (닭고기, 돼지고기 및 쇠고기의 방사선 조사 유무 판별을 위한 ESR Spectroscopy의 활용)

  • Yang, Jae-Seung;Kim, Choong-Ki;Lee, Hae-Jung
    • Korean Journal of Food Science and Technology
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    • v.31 no.3
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    • pp.606-611
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    • 1999
  • To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. Bones cleaned, pieced and dried were irradiated with doses of 0, 1, 3, 5 kGys using a $Co^{60}$ irradiator. The bones were placed in a resonant quartz tube with an internal diameter of about 4.0 mm within the Bruker Win-ESR spectrometer, and the intensity of the ESR signal could be quantified by double integration of the first derivative spectrum. The irradiated bone presented an asymmetric absorption in shape, different from that of an unirradiated one. It could be possible to detect at doses lower than 1 kGy below the dose employed commercially (3 kGy) in the case of irradiated chicken bone. The signal intensity was greatest in the beef bone, intermediate in the pork bone and lowest in the chicken bone; it was normally lower for smaller animals than for larger species, and small variations were observed between samples of the same species. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats.

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