• Publications of The Korean Astronomical Society
• /
• v.30 no.2
• /
• pp.461-462
• /
• 2015

Quasars are among the farthest and brightest objects known in the universe. Because quasars are mostly observed in the redshift range between 1 and 3, they can be used to study large scale structure in the universe, and its evolution over the past billion years. An important issue is the evolution of the quasar luminosity function, which has been investigated for relative small samples of the 2QZ catalog. Here we extend the study to 3 quasar samples, the most recent data of the Milliquas, Master and 2QZ quasar catalogs to determine the luminosity function of quasars and its evolution, using the Standard cosmological ${\Lambda}CDM$ model with ${\Omega}_{\Lambda}=0.73$, ${\Omega}_M=0.27$, and $H_0=70kms^{-1}Mpc^{-1}$. For the purpose of this analysis we initially used 0.25-mag bins and approximately 0.180-redshift bins, then calculated the comoving distance and comoving volume for each bin of redshift and calculated the number of objects in each bin per unit volume, in order to find the number density per absolute magnitude bin. Our analysis on the basis of these new and much more complete datasets is largely in agreement with earlier studies of the luminosity evolution of quasars.

• International Journal of Highway Engineering
• /
• v.15 no.6
• /
• pp.125-133
• /
• 2013

PURPOSES : The purpose of this study is to propose delay-minimizing operation methodology of a signalized intersection based upon optimization of lane-uses on approaching lanes for an intersection. METHODS : For the optimization model of lane-uses, a set of constraints are set up to ensure feasibility and safety of the lane-uses, traffic flow, and signal settings. Minimization of demand to saturation flow ratio of a dual-ring signal control system is introduced to the objective function for delay minimization and effective signal operation. Using the optimized lane-uses, signal timings are optimized by delay-based model of TRANSYT-7F. RESULTS : It was found that the proposed objective function is great relation with delay time for an intersection. From the experimental results, the method was approved to be effective in reducing delay time. Especially, cases for two left-turn lanes reduced greater delays than those for a left turn lane. It is noticed that the cases for different traffic volume by approach reduced greater delays than those for the same traffic volume by approach. CONCLUSIONS : It was concluded that the objective function is proper for lane-uses optimizing model and the operation method is effective in reducing delay time for signalized intersections.

• The Journal of Korean Physical Therapy
• /
• v.31 no.5
• /
• pp.261-265
• /
• 2019

Purpose: This study examined the effects of Vojta therapy on the respiratory function in young male smokers. Methods: Three subjects were tested using the ABA design for Single-subject Experimental Research Design. This study was conducted with the baseline, intervention, and follow-up phase. Intervention was conducted three to four times a week for 20 minutes per times and a total of 25 sessions. The respiratory function was measured using a Spirometer. Results: The results of Forced Vital Capacity and Forced Expiratory Volume at one second for all subjects showed improvements in the intervention phase over the baseline phase. In the follow-up phase, the improved ability was still maintained or slightly reduced. Conclusion: Vojta therapy used on young male smokers was effective in both FVC and FEV1. In other words, the Vojta therapy worked effectively in improving the respiratory function. In future studies, it is necessary to have a control group and increase the number of trials in order to generalize the effect of Vojta therapy.

• Journal of Drive and Control
• /
• v.18 no.2
• /
• pp.20-31
• /
• 2021

An excavator is a construction machine that can perform various tasks such as trenching, piping, excavating, slope cutting, grading, and rock demolishing. In the 2010s, unmanned construction equipment using ICT technology was continuously developed. In this paper, the path design process was studied to implement the output data of the decision stage, and the path design algorithm was developed. For example, the output data of the decision stage were terrain data around the excavator, excavator mechanism information, excavator hydraulic information, the position and posture of the bucket at key points, the speed of the desired bucket path, and the required excavation volume. The result of the path design was the movement of the hydraulic cylinder, boom arm, bucket, and bucket edge. The core functions of the path design algorithm are the function of avoiding impact during the excavation process, the function to calculate the excavation depth that satisfies the required excavation volume, and the function that allows the bucket to pass through the main points of the excavation process while maintaining the speed of the desired path. In particular, in the process of developing the last function, the node tracking method expressed in the path design table was newly developed. The path design algorithm was verified as this path design satisfied the JCMAS H02 requirement.

• The Journal of Korean Physical Therapy
• /
• v.30 no.4
• /
• pp.129-134
• /
• 2018

Purpose: This study aims to investigate the changes in pulmonary function, gait ability, and quality of life when NMES is applied along with CBE and to provide basic clinical data to be used in pulmonary rehabilitation guidelines for patients with COPD to treat patients with severe COPD. Methods: For this study, CBE and NMES of quadriceps femoris on both sides were applied to the experimental group (n=10), and only CBE was applied to the control group (n=10). For a pre-test, a 6-minute walk test was performed, and pulmonary function and health-related quality of life were measured. Moreover, an exercise program was applied to each group for 30 minutes per session, 5 times a week, for 6 weeks. After that, a post-test was conducted the same way as the pre-test. Results: In the within-group comparison, there were significant differences in forced expiratory volume in one second, 6-minute walk test and health-related quality of life between the experimental group and the control group (p<0.01)(p<0.05). In the between-group comparison, the experimental group showed an increase in forced expiratory volume in one second and 6-minute walk test (p<0.05) and showed a decline in health-related quality of life (p<0.05). Conclusion: The 6-weeks NMES program improved health-related quality in patients with severe COPD by increasing expiratory volume by reinforcing the function of quadriceps femoris. This finding implies that NMES could be an alternative mode for improving physical functions of patients with severe COPD, who cannot participate in a breathing exercise program or are reluctant to participate.

• Investigative Magnetic Resonance Imaging
• /
• v.21 no.1
• /
• pp.20-27
• /
• 2017

Purpose: To evaluate quantification results of single breath-hold (SBH) magnetic resonance (MR) cine imaging compared to results of conventional multiple breath-hold (MBH) technique for left ventricular (LV) function in patients with cardiac arrhythmia. Materials and Methods: MR images of patients with arrhythmia who underwent MBH and SBH cine imaging at the same time on a 1.5T MR scanner were retrospectively reviewed. Both SBH and MBH cine imaging were performed with balanced steady state free precession. SBH scans were acquired using temporal parallel acquisition technique (TPAT). Fifty patients ($65.4{\pm}12.3years$, 72% men) were included. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), myocardial mass, and LV regional wall motion were evaluated. Results: EF, myocardial mass, and regional wall motion were not significantly different between SBH and MBH acquisition techniques (all P-values > 0.05). EDV, ESV, and SV were significant difference between the two techniques. These parameters for SBH cine imaging with TPAT tended to lower than those in MBH. EF and myocardial mass of SBH cine imaging with TPAT showed good correlation with values of MBH cine imaging in Passing-Bablok regression charts and Bland-Altman plots. However, SBH imaging required significantly shorter acquisition time than MBH cine imaging ($15{\pm}7sec$ vs. $293{\pm}104sec$, P < 0.001). Conclusion: SBH cine imaging with TPAT permits shorter acquisition time with assessment results of global and regional LV function comparable to those with MBH cine imaging in patients with arrhythmia.

• Journal of the East Asian Society of Dietary Life
• /
• v.15 no.5
• /
• pp.558-565
• /
• 2005

In this study, Schizandriae fructus which has been used in oriental medicine and folks remedy, was studied to apply to functional foods and oriental medicinal cuisine. The aim of this experiments was to investigate the effects of Schizandriae fructus water extract(SFE) on the renal function, plasma renin activity, plasma levels of aldosterone and arterial natriuretic peptide(ANP) in rats. Spargue-Dawley rats weigh 200g, were randomly assigned to 3 groups such as basal diet only(BDG), basal diet with $0.5{\mu}L/g$ SFE(LAG) and basal diet with $1.0{\mu}L/g$ SFE(HAG). The results were as follows. Water balance decreased significantly after administration for 2 weeks compared with the control period in HAG. Urine volume increased significantly after administration for 1 week compared with the control period in LAG and HAG. Urinary excretion of sodium increased significantly after administration for 1 week and for 2 weeks compared with the control period in LAG and HAG. Urinary excretion of creatinine increased significantly after administration for 2 weeks compared with the control period in HAG. Plama levels of ANL decreased significantly after administration of $SFE(0.5{\mu}L/g)$. Plasma levels of aldosterone decreased significantly after administration of $SFE(1.0{\mu}L/g)$. There results indicated that Schizandriae fructus can improve the renal function through increased urine volume and sodium excretion. These results imply that SFE could be used as a potent food resource for diet therapy or clinical nutrition.

• PNF and Movement
• /
• v.12 no.3
• /
• pp.143-150
• /
• 2014

Purpose: The corticospinal tract (CST) is known to be an important pyramidal tract for walking and motor function. However, very little is known about the functional role of the CST in the recovery of motor function. In the current study, we investigated the relation between the CST and motor function in chronic hemiparetic stroke patients. Methods: Fifty-four patients and 20 normal subjects were recruited. The Functional Ambulation Category (FAC) was used in measurement of the walking ability. We classified patients into three groups according to the ability to walk independently: group A, patients who could not walk independently (FAC: 0-2); group B, patients who could walk independently (FAC: 3); and group C, patd walk functionally (stairs and uneven surfaces, FAC 4-5). The Motricity Index (MI) was used to measure the motor function of the affected upper and lower extremities (maximum score: 100). The fractional anisotropy (FA) value, apparent diffusion coefficient (ADC) value, and fiber volume of the CST were used for the diffusion tensor imaging (DTI) parameters. Results: In terms of the CST of the unaffected hemisphere, the FA value of group A was significantly lower than that of normal controls (p <0.05). The fiber volume of group C was significantly higher than that of normal controls (p <0.05). In contrast, the ADC values of all patient groups and the control group did not show any difference (p >0.05). In terms of lower MI and total MI, significant differences were observed between all patient groups (p <0.05). In addition, significant differences in terms of the upper MI scores were observed between groups A and C and between groups B and C (p <0.05); however, no significant difference was observed between groups A and B (p>0.05). Conclusion: The increased fiber volume of the CST in the unaffected hemisphere appears to be related to functional walking ability in chronic stroke patients. This result would be useful for elucidation of the neural recovery mechanism of walking and the investigation of new modalities for the recovery of walking following a stroke with CST injury.

• Journal of Korean Academy of Nursing
• /
• v.21 no.3
• /
• pp.268-280
• /
• 1991

The nursing intervention for the prevention of the pulmonary complication and of the function lowering of pulmonary ventilation which emerge with high generation frequency during the nursing of operation patient is necessary for performing the qualitative nursing for operation patient. So, this researcher tried this study so as to obtain the data which can be utilized for the trial of nursing intervention, by grasping the effect that the deep breathing with Incentive Spirometer has on the function of pulmonary ventilation, analysing the factor to have influence on the function of pulmonary ventilation, and applying the effective method of deep breathing to the clinic. By making 42 patients who underwent the operation of upper abdomen after admitting G Hospital in Seoul from Mar. 7, 1991 to Apr.30, 1991 as the object, they were classified into the experiment group that the deep breathing was made with the use of Incentive Spiromenter and the comparison group that the deep breathing exercise was made without the use of Incentive Spirometer. And then, by measuring Tidal Volume and Forced Vital Capacity with Respirometer and $O_2$ Saturation with Pulse Oximeter at preoperation postoperation 24 hours, 72 hours, and 120 hours data were collected. The collected data were analyzed with of, average, standard deviation, x$^2$-test, t-test and ANOVA by SPSS. The result of this study is as follows : 1. As for the hypothesis that the function of pulmonary ventilation at postoperation 24 hours, 72 hours and 120 hours will be better in the experiment group that the deep breathing was made with the use of Incentive Spirometer, in comparison with the comparison group that deep breathing was made without the use of Incentive Spirometer, experiment group and comparison group didn't show the significant difference in Tidal Volume, Foreced Vital Capacity and $O_2$ Saturation at postoperation 24 hours and 72 hours. But experiment group and comparison group showed the significant difference in Tidal Volume at postoperation 120 hours (p＜0.01). So, this hypothesis was supported partially. 2. The variables that there were the significant differences about the function of pulmonary ventilation in experiment group at postoperation 24 hours stastically were smoking existence (p＜0.05), and the variables that there were not significant differences about the function of pulmonary ventilation were distinction of sex, age, anesthetic duration, smoking extent, body weight, surface area of body, existence of narcotic use, regular exercise existence, and past experience existence of respiratory disease. As above result, it appeared that the method of deep breathing with the use of the Incentive Spirometer is more effective for the function recovery of pulmonary ventilation, in comparison with the deep breathing without use of Incentive Spirometer and that smoking existence was the factor to have influence on the function of pulmonary ventilation. In the aspect of clinic, the trial of nursing intervention of deep breathing with use of Incentive Spirometer is expected. And, in the aspect of study, the study through various operative site patients about the effect of Incentive Spirometer use at the clinic will have to be confirmed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.29 no.12
• /
• pp.628-637
• /
• 2017

This study was conducted to present an effective control method for the common duct system to uniformly discharge volume flow rate exhausted from the kitchen and bathroom of each household in an apartment regardless of the position of household. Since the common duct system is installed vertically and the ventilator is installed in the terminal, the static pressure of each household decreases when vertical height increases. Therefore, the volume flow rate exhausted from each household is different. In order to improve such a phenomenon, a constant air volume damper shall be installed in a branch duct coupled with a common vertical duct system. The selected ventilator should also be able to handle the maximum volume flow rate considering diversity factor. Therefore, a uniform volume flow rate must be exhausted from all households where the hood is operated. This paper mainly focuses on suggestion of an optimum exhaust control method by comparing exhaust performance of each household according to the presence or absence of a constant air volume damper.