• 제목/요약/키워드: chi parameters ($\chi_{12}$)

검색결과 77건 처리시간 0.027초

침전법으로 제조된 전구체 성질에 의한 LiCoO2의 특성에 관한 연구 (Characterization of LiCoO2 Synthesized via Structural and Compositional Variations of Precursors Prepared by Precipitation)

  • 정명국;황치석;최청송
    • 청정기술
    • /
    • 제12권2호
    • /
    • pp.101-106
    • /
    • 2006
  • 본 연구에서는 수산화물 전구체로부터 HT-$LiCoO_2$ 분말을 제조하였다. 사용된 $Co(OH)_2$${\alpha}$상 및, 또는 ${\beta}$ 상의 수산화물이며 여러 조건에서 침전법으로 제조되었다. 제조시에 $[OH^-]/[CO^{2+}]$ 농도 비와 숙성시간을 조절함으로써 원하는 특성을 지닌 $Co(OH)_2$ 제조가 가능하였다. 침전법으로 합성한 $Co(OH)_2$와 LiOH를 메탄올 수용액을 이용하여 혼합한 후 이어서 증발, 건조 그리고 숙성 조작에 의하여 HT-$LiCoO_2$의 전구체를 합성하였다. 숙성기간에 tailor-made ${\beta}$-phase $Co(OH)_2$는 CoOOH로 변환되면서 고용체를 형성한다. 이 같은 결과로 HT-$LiCoO_2$가 낮은 온도($600^{\circ}C$), 짧은 시간(10분)에 합성이 가능하게 된다.

  • PDF

만성 호흡기 질환자의 건강증진행위 구조 모형 (A Structural Model for Health Promoting Behaviors in Patients with Chronic Respiratory Disease)

  • 박영주;김소인;이평숙;김순용;이숙자;박은숙;유호신;장성옥;한금선
    • 대한간호학회지
    • /
    • 제31권3호
    • /
    • pp.477-491
    • /
    • 2001
  • Purpose: This study was designed to construct a structural model for health promoting behavior in patients with chronic respiratory disease. A hypothetical model was developed based on the literature review. Method: Data was collected by questionnaires from 235 patients with chronic respiratory disease in a General Hospital in Seoul. Data analysis was done using SAS 6.12 for descriptive statistics and the PC-LISREL 8.13 Program for Covariance Structural Analysis. Result: The results are as follows : 1. The fit of the hypothetical model to the data was moderate. It was modified by excluding 2 path and including free parameters and 3 path to it. The modified model with path showed a good fitness to the empirical data($\chi$2=80.20, P=0.05, GFI=0.95, AGFI=0.88, NNFI=0.95, NFI=0.96, RMSR=0.01, RMSEA =0.06). 2. The perceived benefits, self-efficacy, and a plan of action were found to have significant direct effects on the health promoting behavior in patients with chronic respiratory disease. 3. The health perception, self-esteem, and activity related to affect were found to have indirect effects on the health promoting behavior in patients with chronic respiratory disease. Conclusion: The modified model of this study is considered appropriate in explaining and predicting health promoting behavior in patients with chronic respiratory disease. Therefore, it can effectively be used as a reference model for further studies and suggested direction in nursing practice.

  • PDF

[ $T_2$ ]-relaxation Time Measurement of ex vivo $^1H$ MR Metabolite Peaks for Evaluation of Human Stomach Cancer

  • Mun Chi-Woong;Choi Ki-Sueng;Shin Oon-Jae;Yang Young-Ill;Chang Hee-Kyung;Hu Xiaoping;Eun Chung-Ki
    • 대한의용생체공학회:의공학회지
    • /
    • 제27권2호
    • /
    • pp.53-58
    • /
    • 2006
  • In this study, transverse relaxation time (T2) measurement and the evaluation of the characteristics of the spectral peak related to stomach tissue metabolites were performed using ex vivo proton magnetic resonance spectroscopic imaging (MRSI) at 1.5-T MRI/S instruments. Thirty-two gastric tissues resected from 12 patients during gastric cancer surgery, of which 19 were normal tissue and 13 were cancerous tissue, were used to measure the $T_2$ of the magnetic resonance spectroscopy (MRS) peaks. The volume of interest data results from the MRSI measurements were extracted from the proper muscle (MUS) layer and the composite mucosa/submucosa (MC/SMC) layer and were statistically analyzed. MR spectra were acquired using the chemical shift imaging (CSI) point resolved spectroscopy (CSI-PRESS) technique with the parameters of pulse repetition time (TR) and echo times (TE) TR/(TE1,TE2)=1500 msec/(35 msec, 144 msec), matrix $size=24{\times}24$, NA=1, and voxel $size=2.2{\times}2.2{\times}4mm^3$. In conclusion, the measured $T_2$ of the metabolite peaks, such as choline (3.21ppm) and lipid (1.33ppm), were significantly decreased (p<0.01 and p<0.05, respectively) in the cancerous stomach tissue.

모노콜정에 대한 콩커정의 생물학적 동등성 평가 (Bioequivalence of Bisoprolol Tablet (Bisoprolol hemifumarate 5 mg))

  • 고인자;지상철
    • 한국임상약학회지
    • /
    • 제14권2호
    • /
    • pp.85-90
    • /
    • 2004
  • Bisoprolol, one of the $\beta_1-adrenorecepter$ antagonist, has been used for the treatment of mild to moderate essential hypertension anti stable angina pectoris. The oral bloavailability of bisoprolo1 is high $(90\%)$ and the drug has a long elimination half-life, $9{\sim}12\;hr$, which allows once-daily administration. The bioequivalence of two bisoprolol preparations was evaluated according to the guidelines of Korea Food & Drug Administration (KFDA). The test product was Concor $tablet^{(R)}$ made by Newgenpharm and the reference product was Monocor $tablet^{(R)}$ made by Wyeth Korea. Twenty healthy male subjects, 23.8 (21-30) years old and 03.8(52-92) kg, were randomly divided into two groups and a randomized $2\times2$ cross-over study was employed. After two tablets containing 10 mg bisoprolol hemifumarate were orally administered, blood was taken at predetermined time intervals and the concentration of bisoprolol in plasma was determined using an HPLC method with fluorescence detector. Two pharmacokinetic parameters, $AUC_t\;and\;C_{max}$ were calculated and analyzed statistical]y for the evaluation of bioequivalence of the two products. Analysis of variance was carried out using logarithmically transformed parameter values. The $90\%$ confidence intervals of $AUC_t\;and\;C_{max}$ were log $0.95{\sim}1og\;1.04\;and\;1og\;0.96{\sim}1og\;1.07,\;respectively.$ These values were within the acceptable bioequivalence intervals of log $0.8{\sim}log\;1.23$. Thus, the criteria of the KFDA guidelines for the bioequivalence was satisfied, indicating that Concor tablet is bioequivalent to Monocor tablet.

  • PDF

생체내 예측 및 흰쥐를 이용한 니코틴 패취의 약물동력학적 평가 (In Vivo Prediction and Biopharmaceutical Evaluation of Nicotine Transdermal Patch)

  • 이우영;백승희;박은석;지상철
    • Journal of Pharmaceutical Investigation
    • /
    • 제35권4호
    • /
    • pp.273-278
    • /
    • 2005
  • Nicotine transdermal therapeutic systems $(TTS_S)$ have been regarded as an effective mean to aid smoking cessation. However, most of nicotine $TTS_S$ in the market have some problems such as unpleasant side effects and skin irritation due to the excess amount of the drug permeated and the properties of the additives employed. In order to solve these problems, new nicotine $TTS_S$ were formulated using biocompatible additives. The optimized formula of the drug layer consisted of nicotine, propylene glycol and poloxamer 188 at the ratio of 1.2: 17.0: 2.0. The drug layer had the sickness of $1,250\;{\mu}m$, the pH of 8.12. The skin permeation rate of nicotine from optimized nicotine patch (NP) was $21.5\;{\mu}g/cm^2/h$. Transdermal administration of nicotine patch has been carried out for the determination of pharmacokinetic parameters in rats. Steady-state plasma concentration of nicotine following transdermal application of NP (area of patch = $15\;cm^2$) on the dorsal skin of rats was 143.2 ng/ml and AUC for 24 hrs was 3,022 ng h/ml. In case of $EXODUS^{\circledR}$ and Nicotinell $TTS^{\circledR}$, the steady-state plasma concentration of nicotine and ACU for 24 hrs were 428.9 ng/ml, $9,121\;ng{\cdot}hr/ml$ and 155.3 ng/ml, $3,152\;ng{\cdot}h/ml$, respectively. NP showed the experimental plasma nicotine concentration profile was very similar to the simulated one and had an appropriate skin permeation rate and a steady-state concentration of nicotine, which can show therapeutic blood levels of the drug for 24 hrs without severe side effects.

Predictive models of hardened mechanical properties of waste LCD glass concrete

  • Wang, Chien-Chih;Wang, Her-Yung;Huang, Chi
    • Computers and Concrete
    • /
    • 제14권5호
    • /
    • pp.577-597
    • /
    • 2014
  • This paper aims to develop a prediction model for the hardened properties of waste LCD glass that is used in concrete by analyzing a series of laboratory test results, which were obtained in our previous study. We also summarized the testing results of the hardened properties of a variety of waste LCD glass concretes and discussed the effect of factors such as the water-binder ratio (w/b), waste glass content (G) and age (t) on the concrete compressive strength, flexural strength and ultrasonic pulse velocity. This study also applied a hyperbolic function, an exponential function and a power function in a non-linear regression analysis of multiple variables and established the prediction model that could consider the effect of the water-binder ratio (w/b), waste glass content (G) and age (t) on the concrete compressive strength, flexural strength and ultrasonic pulse velocity. Compared with the testing results, the statistical analysis shows that the coefficient of determination $R^2$ and the mean absolute percentage error (MAPE) were 0.93-0.96 and 5.4-8.4% for the compressive strength, 0.83-0.89 and 8.9-12.2% for the flexural strength and 0.87-0.89 and 1.8-2.2% for the ultrasonic pulse velocity, respectively. The proposed models are highly accurate in predicting the compressive strength, flexural strength and ultrasonic pulse velocity of waste LCD glass concrete. However, with other ranges of mixture parameters, the predicted models must be further studied.

Assessment of demographic and clinical data related to dental implants in a group of Turkish patients treated at a university clinic

  • Bural, Canan;Bilhan, Hakan;Cilingir, Altug;Geckili, Onur
    • The Journal of Advanced Prosthodontics
    • /
    • 제5권3호
    • /
    • pp.351-358
    • /
    • 2013
  • PURPOSE. This retrospective study analyzed the distribution of the dental implants with regards to age and gender of the patients and type of indication for the implant therapy, as well as the location, dimension and type of the implants. MATERIALS AND METHODS. The data of demographics (age and gender), type of indication for implant therapy, anatomical location, dimensions (length and diameter) and type (bone and tissue level) of 1616 implants were recorded from patient charts between January 2000 and January 2010. Descriptive statistics were analyzed using a chi-squared test for demographic parameters, type of indication, tooth position, anatomical location, implant dimensions and type (${\alpha}$=.05). RESULTS. The patient pool comprised of 350 women and 266 men, with a mean age of $52.12{\pm}13.79$ years. The difference in n% of the implants of the age groups was statistically significant between the types of indications. The difference in the position of the implants was statistically significant between the n% of the implants of all age groups. Gender did not significantly vary, except that the diameter of the implants was significantly higher for the standard diameter implants in males. The difference between the implant positions was statistically significant when considered according to indication. The relationship between implant length and anatomical location was statistically significant. CONCLUSION. The indication for dental implant use is age dependent and the type and size of the implant seems to be strongly related to the location of the implant.

Cardiac Troponin I Elevation in Patients with Aneurysmal Subarachnoid Hemorrhage

  • Jeon, Ik-Chan;Chang, Chul-Hoon;Choi, Byung-Yon;Kim, Min-Su;Kim, Sang-Woo;Kim, Seong-Ho
    • Journal of Korean Neurosurgical Society
    • /
    • 제46권2호
    • /
    • pp.99-102
    • /
    • 2009
  • Objective: Cardiac dysfunction after aneurysmal subarachnoid hemorrhage (SAH) is associated with elevation of serum cardiac troponin I (cTnl) levels. Elevation of cTnl predicts cardiopulmonary and neurological complications, and poor outcome. Methods: We retrospectively reviewed the medical and radiologic records of 114 (male: 30, female: 84) patients who developed aneurysmal SAH between January 2006 and June 2007 and had no history of previous cardiac problems. We evaluated their electrocardiography and cTnl level, which had been measured at admission. A cTnl level above 0.5 $\mu$g/L was defined as an indicator of cardiac injury following SAH. We examined various clinical factors for their association with cTnl elevation and analyzed data using chi-square test, t-test and logistic regression test with SPSS version 12.0. The results were considered significant at p< 0.05. Results: The following parameters shows a correlation with cTnl elevation: higher Hunt-Hess (H-H) grade (p = 0.000), poor Glasgow Outcome Scale (GOS) score (p = 0.000), profound pulmonary complication (p = 0.043), higher heart rate during initial three days following SAH (p = 0.029), ruptured aneurysm on communicating segment of internal carotid artery (p = 0.025), incidence of vasospasm (p = 0.421), and duration of hyperdynamic therapy for vasospasm (p = 0.292). A significant determinants for outcome were cTnl elevation (p = 0.046) and H-H grade (p = 0.000) in a multivariate study. Conclusion: A cTnl is a good indicator for cardiopulmonary and neurologic complications and outcome following SAH. Consideration of variable clinical factors that related with cTnl elevation may be useful tactics for treatment of SAH and concomitant complications.

로터리 스웨이징 공정의 점진성형에 의한 중공 드라이브샤프트의 진동모드 및 내구특성 (Vibration Mode and Durability Characteristics of Automotive IDS using Rotary Swaging Process for Incremental Forming)

  • 임성주;이낙규;이지환
    • 한국자동차공학회논문집
    • /
    • 제13권5호
    • /
    • pp.127-133
    • /
    • 2005
  • Rotary swaging is one of the incremental forming process which is a chipless process using the reduction of cross-sections of bars, tubes and wires. The TDS(Tube Drive Shaft) of monobloc used in automotive has been developed by the rotary swaging process. The mechanical characteristics of swaged parts such as the hardness, thickness and roughness are also estimated to conduct experimental analyses of rotary swaging process with the materials of 34Mn5 Furthermore the change in the vibration mode of TDS due to design parameters, which are the tube length, diameter and thickness, has been investigated and analysed. The weight of the TDS product is smaller by about $12.8\%$ than that of SDS with the same performance. It could be evidently found that the TDS is designed to be much lighter than SDS (Solid Drive Shaft). This advantage might give some possibility to improve the NVH (Noise-Vibration-Harshness) characteristics. A maximum torque and a total number of torsional repetitions for the TDS is checked and measured to know the torsional intensity and fatigue strength through the static torsion test and torsional durability test, respectively. A total number of the torsional repetitions up to the fracture for the TDS is greater than 250,000 times.

Endometrial histology and predictable clinical factors for endometrial disease in women with polycystic ovary syndrome

  • Park, Joon-Cheol;Lim, Su-Yeon;Jang, Tae-Kyu;Bae, Jin-Gon;Kim, Jong-In;Rhee, Jeong-Ho
    • Clinical and Experimental Reproductive Medicine
    • /
    • 제38권1호
    • /
    • pp.42-46
    • /
    • 2011
  • Objective: This study was aimed to investigate endometrial histology and to find predictable clinical factors for endometrial disease (hyperplasia or cancer) in women with polycystic ovary syndrome (PCOS). Methods: We investigated the endometrial histology and analyzed the relationship between endometrial histology and clinical parameters, such as LH, FSH, estradiol, testosterone, fasting and 2 hours postprandial glucose and insulin, insulin resistance, body mass index, endometrial thickness, menstrual status from 117 women with PCOS. Statistical analysis was performed with chi square and t-test, p-value<0.05 was considered as statistically significant. And receiver operating characteristic curve was used to find predictable clinical factors for endometrial disease and to decide the cuff off values. Results: In 117 women with PCOS, endometrial histologic profiles are as follows: proliferative phase in 90 women (76.9%), endometrial hyperplasia in 25 women (21.4%), and endometrial cancer in 2 women (1.7%). Of 25 women with endometrial hyperplasia, simple hyperplasia without atypia, complex hyperplasia without atypia and complex hyperplasia with atypia were diagnosed in 15 (12.8%), 6 (5.1%), 4 (3.4%) women, respectively. Age and endometrial thickness were significantly related with endometrial disease, p=0.013 and p=0.001, respectively. At the cut off level of 25.5 years in age, sensitivity and specificity predicting for endometrial disease were 70.4% and 55.6%, respectively (p=0.023). At the cut off level of 8.5 mm in endometrial thickness, sensitivity and specificity were 77.8% and 56.7%, respectively (p=0.000). Conclusion: In women with PCOS, the incidence of endometrial hyperplasia and cancer were 21.4% and 1.7%. The age and endometrial thickness may be used as clinical determining factors for endometrial biopsy.