• Title/Summary/Keyword: 3-Mass System

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A STUDY ON THE BONE MINERAL DENSITY OF ILIAC AND TIBIAL BONE USING DUAL ENERGY X-RAY ABSORPTIOMETRY (이중에너지 방사선 흡수계측법을 이용한 성인 남녀의 장골 및 경골의 골밀도에 관한 연구)

  • Cho, Yong-Seok;Kim, Kyoung-Won;Lee, Keong-Ho;Park, Hyun-Jin;Seo, Sang-Su;Oh, Sang-Youp
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.22 no.3
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    • pp.265-273
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    • 2000
  • Purpose : The aim of this study was to evaluate the bone mineral density of iliac and tibial bone which are frequently selected as autogenic bone graft donor sites, and to evaluate the efficiency of this method as a guideline for the selection of bone graft donor site. Materials and Methods : In this study 61 male and 70 female volunteers at Chungbuk National University Hospital were involved between Jan. 1998 to Sept. 1999. We measured bone mineral density of the iliac and the tibial bone using dual energy X-ray absorptiometry. We evaluated the data using the SAS system for Windows and bone mineral density of the lumbar was used for control. Results : Age showed the highest correlation in correlation matrix between physical and bone variables. Height and weight showed lower correlation of linear increment. In man, the change of bone density according to age demonstrated linear decrease irrespective of the lumbar, ilium, and tibia. In woman, the change of bone density according to age showed cubic form, which increased in the third and forth decade. So it had a peak bone mass on about 35 year-old, thereafter, the change of bone density slowly decreased until 50 year-old, but it rapidly decreased after 50 year-old and it slowly decreased again after 65 year-old. Both in all subjects and subject with osteoporosis, the change of bone mineral density according to age showed statistically significant decrease in lumbar and tibia, but ilium was irrespective. Conclusion : In patients of aged or with osteoporosis, ilium demonstrated less tendency of decrease in bone mineral density than tibia. So this preliminary study suggested that ilium seemed better donor site for autogenic bone graft than tibia.

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MULTIPLE MYELOMA IN THE MANDIBLE MANIFESTED AS ORAL LESION OF PLASMACYTOMA: A CASE REPORT (악골에서 발견된 multiple myeloma의 구강내 plasmacytoma 병소: 증례보고)

  • Lee, Jeong-A;Park, Ji-Young;Yun, Sung-Hun;Park, Min-Kyu;Kim, Chang-Hyun;Park, Je-Uk
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.29 no.1
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    • pp.85-90
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    • 2007
  • Plasma cell neoplasms are generally categorized into four groups; multiple myeloma(MM), solitary plasmacytoma of the bone(SPB), plasma cell leukemias, and extramedullary plasmacytomas(EMP). These tumors may be further described as localized or diffuse in presentation. Localized plasma cell neoplasms are rare occurrences and include solitary plasmacytomas of the skeletal system, which account for 2-5% of all plasma cell neoplasms and extramedullary plasmacytomas of the soft tissue, which account for approximately 3% of all such neoplasms. A plasmacytoma is defined as any discrete, most likely solitary mass of neoplastic plasma cells either in the bone marrow or in various soft tissue sites. Diffuse lesions include the other two groups, multiple myeloma and plasma cell leukemia. The relationship between these processes has not yet been definitively characterized, but there appears to be a continuum in which both SPB and EMP often progress to MM. The patient was referred who had continuous deep throbbing bone pain and swelling on the left posterior gingival area of the mandible after extraction of the first and second molar. The result of intraoperative excisional biopsy of the lesion was confirmed as a plasmacytoma. And it revealed systemic multiple myeloma through the further diagnostic work-up. It is worth to report because of a rare case of multiple myeloma found in oral cavity as a form of plasmacytoma.

Modeling of the Charge-discharge Behavior of a 12-V Automotive Lead-acid Battery (차량용 12-V 납축전지의 충·방전 모델링)

  • Kim, Ui Seong;Jeon, Sehoon;Jeon, Wonjin;Shin, Chee Burm;Chung, Seung Myun;Kim, Sung Tae
    • Korean Chemical Engineering Research
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    • v.45 no.3
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    • pp.242-248
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    • 2007
  • For an optimal design of automotive electric system, it is important to have a reliable modeling tool to predict the charge-discharge behaviors of the automotive battery. In this work, a two-dimensional modeling was carried out to predict the charge-discharge behaviors of a 12-V automotive lead-acid battery. The model accounted for electrochemical kinetics and ionic mass transfer in a battery cell. In order to validate the modeling, modeling results were compared with the experimental data of the charge-discharge behaviors of a lead-acid battery. The discharge behaviors were measured with three different discharge rates of C/5, C/10, and C/20 at operating temperature of $25^{\circ}C$. The batteries were charged with constant current of 30A until the charging voltage reached to a predetermined value of 14.24 V and then the charging voltage was kept constant. The discharge and charge curves from the measurements and modeling were in good agreement. Based on the modeling, the distributions of the electrical potentials of the solid and solution phases, the porosity of the electrodes, and the current density within the electrodes as well as the acid concentration can be predicted as a function of charge and discharge time.

A Study on the Development of Transfer Papers -Focused on Tile Design for Remodeling- (전사지 개발에 대한 연구 -리모델링을 위한 타일디자인을 중심으로-)

  • 모인순
    • Archives of design research
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    • v.15 no.2
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    • pp.213-222
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    • 2002
  • A transfer paper, is needed in the third firing, is usually utilized for industrial ceramics in order to produce tablewares or promoting products. Products may have the same form, however; the price might be different by what kinds of design have transferred. We need to fully understand these methods in order to create high value and quality. Remodeling, the so-called second architecture, results from social Needs for renovation of structures and changing functions. Tile satisfying the need for a custom-made design which fits the features of a space. Most importantly, the remodeler must make an individual design ordered for the customer with an emphasis on economy and time efficiency. Tiles currently in the market are mass-produced using an automated system with a high-priced mold. It is difficult to find tiles of distinct design that are made in a small quantity. We need to develop a method for making various kinds of tile designs that would be marketed for the remodeling industry. In this study, after designing a certain wall with the tiffs in the space, 1 will talk about developing a method to make transfer paper to produce individual tiles for the space. 1 hope that the functional and aesthetic effect on remodeling will gain in popularity, and that we will foster a new demand for tiles in harmony with the other materials mentioned in this study.

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Analysis of 6-Beam Accelerometer Using (111) Silicon Wafer by Finite Element Method ((111) 실리콘 웨이퍼를 이용한 6빔 가속도센서의 유한요소법 해석)

  • Sim, Jun-Hwan;Kim, Dong-Kwon;Seo, Chang-Taeg;Yu, In-Sik;Lee, Jong-Hyun
    • Journal of Sensor Science and Technology
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    • v.6 no.5
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    • pp.346-355
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    • 1997
  • In this paper, the analyses of the stress disturibution and frequency characteristics of silicon microstructures for an accelerometer were performed using the general purpose finite element simulation program, ANSYS. From the analyses, we determined the parameter values of a new 6-beam piezoresistive accelerometer applicable to the accelerometer's specification in airbag system of automobile. Then, the mass paddle radius, beam length, beam width, and beam thickness of the designed accelerometer were$500{\mu}m$, $350{\mu}m$, $100{\mu}m$, and $5{\mu}m$, respectively and two different seismic masses with 0.4 mg and 0.8 mg were defined on the same sensor structure. The designed 6- beam accelerometers were fabricated on the selectively diffused (111)-oriented $n/n^{+}/n$ silicon substrates and the characteristics of the fabricated accelerometers were investigated. Then, we used a micromachining technique using porous silicon etching method for the formation of the micromechanical structure of the accelerometer.

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True Triaxial Physical Model Experiment on Brittle Failure Grade and Failure Initiation Stress (취성파괴수준과 파괴개시시점에 관한 진삼축 모형실험연구)

  • Cheon, Dae-Sung;Park, Chan;Park, Chul-Whan;Jeon, Seok-Won
    • Tunnel and Underground Space
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    • v.17 no.2 s.67
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    • pp.128-138
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    • 2007
  • At low in-situ stress, the continuity and distribution of natural fractures in rock mass predominantly control the failure processes. However at high in-situ stress, the failure process are affected and eventually dominated by stress-induced fractures preferentially growing parallel to the excavation boundary. This fracturing is often observed in brittle type of failure such as slabbing or spatting. Recent studies on the stress- or excavation-induced damage of rock revealed its importance especially in a highly stressed regime. In order to evaluate the brittle failure around a deep underground opening, physical model experiments were carried out. For the experiments a new tue triaxial testing system was made. According to visual observation and acoustic emission detection, brittle failure grades were classified under three categories. The test results indicate that where higher horizontal stress, acting perpendicular $(S_{H2})$ and parallel $(S_{H1})$ to the axis of the tunnel respectively, were applied, the failure grade at a constant vertical stress level (Sy) was lowered. The failure initiation stress was also increased with the increasing $S_{H1}\;and\;S_{H2}$. From the multi-variable regression on failure initiation stress and true triaxial stress conditions, $f(S_v,\;S_{H1},\;S_{H2})$ was proposed.

A Survey on Heavy Metal Contents and Transfer Rate in Animal Medicines (동물성 생약의 중금속 함량 및 이행률 조사)

  • Lee, Sung-Deuk;Lee, Jeong-Sook;Hwang, Kwang-Ho;Kim, Hee-Soon;Yoo, In-Sil;Han, Ki-Young;Chae, Young-Zoo
    • YAKHAK HOEJI
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    • v.57 no.1
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    • pp.8-17
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    • 2013
  • The objective of this study is investigation of contamination levels and transfer rate of heavy metals and assessment of health risk effects in animal medicines. A total of sixteen items with 148 samples were obtained for this investigation from major herbal medicine producing areas and herbal markets from 2011 to 2012. Inductively coupled plasma mass spectrometer method was conducted for the quantitative analysis of Pb, Cd and As. In addition, the mercury analyzer system was conducted for that of Hg without sample digestion. The average contents of heavy metals in animal medicines were as follows : 1.55 mg/kg for Pb, 0.28 mg/kg for Cd, 0.70 mg/kg for As and 0.047 mg/kg for Hg respectively. The average contents of heavy metals in decoctions were as follows : 0.03 mg/kg for Pb, 0.01 mg/kg for Cd, 0.17 mg/kg for As and 0.003 mg/kg for Hg respectively. The average transfer rates of heavy metals from animal medicines to decoctions were 1.9% for Pb, 3.6% for Cd, 24.2% for As and 6.0% for Hg respectively. Cancer risks of animal medicines and decoctions through slope factor by ministry of environment republic korea and environmental protection agency was $1.36{\times}10^{-6}$ and $2.50{\times}10^{-8}$ for Pb and $7.46{\times}10^{-5}$ and $1.98{\times}10^{-5}$ for As (assuming that the total arsenic content was equal to the inorganic arsenic) respectively. The hazard index of heavy metals in animal medicines and decoctions was below recommended hazard index as 0.52 and 0.05 respectively. Taken together, cancer risks about Pb and hazard indexes of animal medicines and decoctions indicate that the majority of samples except for some samples with relative high contents of heavy metals were safe. But cancer risks about As of animal medicines indicate that the majority of samples were not relatively safe.

Current Research Trends on Prevalence, Correlates with Cognitive Function, and Intervention on Sarcopenia in Community-dwelling Older Adults: Systematic Review (지역사회 거주 노인의 근감소증 유병률, 인지기능과의 관계 및 중재연구 동향: 체계적 문헌고찰)

  • Ahn, Soojung;Chu, Sang Hui;Jung, Hyejeong
    • 한국노년학
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    • v.36 no.3
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    • pp.727-749
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    • 2016
  • This systematic review was performed to investigate relationship between sarcopenia and cognitive function among community-dwelling older adults. Studies which reported prevalence rates of sarcopenia in community-dwelling older adults, relationships between sarcopenia and cognitive dysfunction, or effective interventions in alleviated symptoms of sarcopenia were selected. Of 43 studies reviewed, prevalence rate of sarcopenia ranged from 2.5-42.4% in 25 studies, and 4 studies revealed a significantly positive correlation between sarcopenia and cognitive dysfunction. Among 12 randomized-control trials (RCTs), exercise intervention was used in 2 studies; nutrition intervention in 6; and 4 studies included both the exercise and nutrition interventions. All interventional studies reported positive effects on muscle mass, muscle strength, or physical function. However, only 6 studies met the high quality criteria of Risk of Bias, and there was no study which evaluated cognitive function as an outcome measure. Therefore, this study draws attention to the lack of high-quality RCTs and exclusion of cognitive function as an outcome measure in the research of sarcopenia. A comprehensive and sustained system including standardized sarcopenia screening, assessments of cognitive functioning, and evidence-based intervention programs is needed in order to prevent and manage sarcopenia amongst older adults in the community.

Impact of NR1I2, adenosine triphosphate-binding cassette transporters genetic polymorphisms on the pharmacokinetics of ginsenoside compound K in healthy Chinese volunteers

  • Zhou, Luping;Chen, Lulu;Wang, Yaqin;Huang, Jie;Yang, Guoping;Tan, Zhirong;Wang, Yicheng;Liao, Jianwei;Zhou, Gan;Hu, Kai;Li, Zhenyu;Ouyang, Dongsheng
    • Journal of Ginseng Research
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    • v.43 no.3
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    • pp.460-474
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    • 2019
  • Background: Ginsenoside compound K (CK) is a promising drug candidate for rheumatoid arthritis. This study examined the impact of polymorphisms in NR1I2, adenosine triphosphate-binding cassette (ABC) transporter genes on the pharmacokinetics of CK in healthy Chinese individuals. Methods: Forty-two targeted variants in seven genes were genotyped in 54 participants using Sequenom MassARRAY system to investigate their association with major pharmacokinetic parameters of CK and its metabolite 20(S)-protopanaxadiol (PPD). Subsequently, molecular docking was simulated using the AutoDock Vina program. Results: ABCC4 rs1751034 TT and rs1189437 TT were associated with increased exposure of CK and decreased exposure of 20(S)-PPD, whereas CFTR rs4148688 heterozygous carriers had the lowest maximum concentration ($C_{max}$) of CK. The area under the curve from zero to the time of the last quantifiable concentration ($AUC_{last}$) of CK was decreased in NR1I2 rs1464602 and rs2472682 homozygous carriers, while $C_{max}$ was significantly reduced only in rs2472682. ABCC4 rs1151471 and CFTR rs2283054 influenced the pharmacokinetics of 20(S)-PPD. In addition, several variations in ABCC2, ABCC4, CFTR, and NR1I2 had minor effects on the pharmacokinetics of CK. Quality of the best homology model of multidrug resistance protein 4 (MRP4) was assessed, and the ligand interaction plot showed the mode of interaction of CK with different MRP4 residues. Conlusion: ABCC4 rs1751034 and rs1189437 affected the pharmacokinetics of both CK and 20(S)-PPD. NR1I2 rs1464602 and rs2472682 were only associated with the pharmacokinetics of CK. Thus, these hereditary variances could partly explain the interindividual differences in the pharmacokinetics of CK.

The Relationship between Obesity and Cardiac Autonomic Regulation in College-Aged Male Smokers (남자흡연대학생의 비만과 심장자율신경조절의 관련성)

  • Kim, Choun Sub;Kim, Maeng Kyu
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.1
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    • pp.142-152
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    • 2019
  • This study aimed to explore the association between obesity index and heart rate variability (HRV) in college-aged male smokers. A total of 85 male college students (> 10 cigarettes per day for at least 3 years) were participated in this study. According to a standardized protocol, body mass index (BMI), percent body fat (%BF), waist circumference (WC), and waist-to-hip ratio (WHR) were taken as obesity indices. Resting r-r interval was monitored for HRV analysis as an indicator of cardiac autonomic regulation. Compared with low WHR subjects, high WHR subjects had significantly lower values of rMSSD, pNN50, HF, and SD1, suggesting decreased parasympathetic activity. No such differences in LF/HF ratio were found between the WHR-based subgroups. Bivariate correlation analysis showed that obesity indices of WC, WHR, and %BF were significantly associated with rMSSD, pNN50, HF, and SD1, with a tendency for correlation coefficient to be higher with WHR than with WC or %BF. No significant association was found between BMI and HRV parameters indicative of parasympathetic activity. This study suggest that central obesity is significantly associated with decrease in parasympathetic activation, independent of BMI as an indicator of obesity, in male college smokers.