• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2600-2605
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• 2008

Turbo-fans for a FFU unit should be aerodynamically designed to provide the FFU system with the given flow-rate at the lowest rotational-speed by considering the interaction effect with the FFU casing. In this study, slim and highly efficient turbo-fans are designed to satisfy the given performance at the specific speed by using the hybrid-stacking method of an inducer and a 2D-bladed turbo fan. The mean-line analysis, cascade theory, and CFD technique are all together applied to control the passage areas on the meridional plane from the inlet to the exit of the blade. Furthermore, the torque control algorithm is adopted to improve the performances within the constraints by the motor rpm-torque characteristics, and the resulting measured performances of mock-up fans are discussed.

• International Journal of Fluid Machinery and Systems
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• v.8 no.4
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• pp.221-229
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• 2015

For efficient design process of regenerative blower, the present study provides new generalized pressure and leakage flow loss models, which can be used in the performance analysis method of regenerative blower. The present performance analysis on designed blower is made by incorporating momentum exchange theory between impellers and side channel with mean line analysis method, and its pressure loss and leakage flow models are generalized from the related fluid mechanics correlations which can be expressed in terms of blower design variables. The present performance analysis method is applied to four existing models for verifying its prediction accuracy, and the prediction and the test results agreed well within a few percentage of relative error. Furthermore, the present performance analysis method is also applied in developing a new blower used for fuel cell application, and the newly designed blower is manufactured and tested through chamber-type test facility. The performance prediction by the present method agreed well with the test result and also with the CFD simulation results. From the comparison results, the present performance analysis method is shown to be suitable for the actual design practice of regenerative blower.

• International Journal of Highway Engineering
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• v.10 no.1
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• pp.145-154
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• 2008

The purpose of this study is to evaluate the quality of on-line departure time-based link travel time estimates. For this, accuracy (i.e. estimation error) and timeliness (i.e. degree of time lag) are proposed as MOE of the quality of on-line link travel time estimates. Then the relationship between quality of link travel time estimates and link length and level of congestion is analyzed. It was found that there is trade-off between the accuracy and timeliness of link travel time estimates. The estimation error was modeled to consist of two components: one is systematic error and the other is mean square error which reflects level of congestion. further, time lag was again segmented into three parts for the analysis purpose. There are minimum one, congestion-related one, and update interval-related one. From the real-world data using AVI system, it was revealed that regardless of the link length and level of congestion, 10 minutes of time lag occurs in general.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.6001-6006
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• 2015

Background: Pancreatic cancer is the fourth leading cause of cancer related death with median survival ranging from 3 to 6 months for metastatic disease. Palliative chemotherapy has been the backbone of treatment in advanced stage and has evolved over time. Data pertaining to the disease are scarce from our part of the world where treatment poses a significant challenge due to lack of resources. Materials and Methods: A retrospective chart review was performed for all patients presenting with stage IV pancreatic carcinoma at a tertiary care hospital in Karachi, Pakistan between January 2008 and December 2012. Data were collected using a pre-designed, coded questionnaire looking at patient characteristics, treatment given and outcome. Results: 101 patients were found to be eligible. Mean age was $56.7{\pm}12.8years$, the male to female ratio was 2:1 and most patients had a good performance status. More than half of the tumors were located in the head (57%, n=58) and almost all were adenocarcinomas (95%, n=96). Some 58% (n=59) received first line chemotherapy of which 49% (n=29) received gemcitabine-based regimens and 39% (n=23) received FOLFIRINOX. The median progression free survival for gemcitabine based treatment was 2.9 months (IQR=1.6-5.6) as opposed to 7.3 months (IQR=4.5-9.2) for FOLFIRINOX (P=0.02). Median overall survival was 4.9 months (IQR=2.3-9.5) for first line gemcitabine based treatment and 10.5 months (IQR=7.0-13.2) for first line FOLFIRINOX therapy (P=0.002). Patients on FOLFIRINOX had better survival across all subgroups. Inpatient admissions and dose reductions were more frequent with FOLFIRINOX but the difference between the two regimens was not statistically significant. FOLFIRINOX could be successfully administered as outpatient therapy to a number of patients. Conclusions: FOLFIRINOX remains a suitable first line option in patients with metastatic pancreatic cancer with good performance status even in a resource-poor country where diagnostic and supportive care facilities may be less than optimal and cost is a limitation.

• Journal of Korean Neurosurgical Society
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• v.51 no.1
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• pp.31-36
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• 2012

Objective : The purpose of this study was to elucidate the anatomical development of physiologic suture closure processes in infants using three dimensional reconstructed computed tomography (CT). Methods : A consecutive series of 243 infants under 12 months of age who underwent three dimensional CT were included in this study. Four major cranial sutures (sagittal, coronal, lambdoidal and metopic suture) were classified into four suture closure grades (grade 0=no closure along the whole length, grade 1=partial or intermittent closure, grade 2=complete closure with visible suture line, grade 3=complete fusion (ossification) without visible suture line), and measured for its closure degree (suture closure rates; defined as percentage of the length of closed suture line divided by the total length of suture line). Results : Suture closure grade under 12 months of age comprised of grade 0 (n=195, 80.2%), grade 1 (n=24, 9.9%) and grade 2 (n=24, 9.9%) in sagittal sutures, whereas in metopic sutures they were grade 0 (n=61, 25.1%), grade 1 (n=167, 68.7%), grade 2 (n=6, 24%) and grade 3 (n=9, 3.7%). Mean suture closure rates under 12 months of age was 58.8% in metopic sutures, followed by coronal (right : 43.8%, left : 41.1%), lambdoidal (right : 27.2%, left : 25.6%) and sagittal sutures (15.6%), respectively. Conclusion : These quantitative descriptions of cranial suture closure may help understand the process involved in the cranial development of Korean infants.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.3
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• pp.219-237
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• 2003

he purpose of this study was to compare the fracture resistance of the IPS Empress ceramic crown with 1.0mm width rounded shoulder, which is usually recommended in all ceramic crown, and 0.5mm width chamfer finish lines on the maxillary first premolar. 30 sound maxillary first premolars were selected and then storaged in 5% NaOCl and saline. 15 teeth were performed preparation for each group(1.0mm rounded shoulder, 0.5mm chamfer). After 30 stone dies were made for each group, the IPS Empress ceramic crowns were fabricated and cemented with resin cement(Bistite resin cement, Tokuyama Soda Co. LTD., Japan) on the natural teeth. The cemented crowns were mounted on the positioning jig and the universal testing machine(Zwick Z020, Zwick Co., Germany)was used to measure the fracture strength, with stress loading on the occlusal surface between buccal and lingual cusp. And also, three-dimensional finite element model was used to measure the stress distribution with two types of the finish lines(1.0mm rounded shoulder, 0.5mm chamfer) and two loading conditions(both buccal and lingual cusp inclination, lingual cusp inclination only). The result of the this study were as follows. In the fracture resistance experiment according to the finish line, the mean fracture strength of rounded shoulder(842N) showed higher value than that of the chamfer(590N) (p<0.05). In the three dimensional finite element analysis of all ceramic crown, metal die and natural teeth model did not show any differences in stress distribution between finish lines. Generally, when force was loaded on the occlusal inclination of buccal and lingual cusp, the stress was concentrated on the loading point and the central groove of occlusal surface. When force was loaded only on the occlusal inclination of lingual cusp, the stress was concentrated on the lingual finish line and loading point.

• Journal of the Korean Institute of Landscape Architecture
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• v.14 no.1
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• pp.45-60
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• 1986

The purpose of the present studies is to establish more rational and practical planning theory for trails of gradient. The results drawn from this research work are as follow ; Mean angle according to topography of Jiga road is $3^{\circ}$33'in low part, $8^{\circ}$17'in middle park and $12^{\circ}$48'in high part. Here, we can find that the highest gradient of Jige roacl is $12^{\circ}$48, Which is showing the fact that jigs road is the most function road when we compare other roads. The regression coefficient between potential model pattern and calculuted model pattern is 0.8 withinTEX>$ 0~<5^{\circ}$, 0.5 within$ 6~10^{\circ}$, and 0.53 within $11~16^{\circ}$. The linear of these model pattern is lower in R & L value, and lager in S & A value according to be steeping gradient. It is thought that these fact are closely related with between human fatigue and R.S.A.L value. Accordingly, when we plan the trails of the gradient in city park, the from of trails is right to mix straight line with curve line within $0~5^{\circ}$, and sine wave close curve line within $6~10 ^{\circ}$, $l1~16^{\circ}$. But, in fact, It is absurd that potential model pattern is applied to the city park in park of corner, widely road and facilities. Therefore, It is thought that the study of this problems will be proceeded in the future. I can reduce the following equation in relation R & S by gradient ; 22 log (R-6.0)=47.96-$\delta$

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.1025-1029
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• 2012

Objective: To determine the killing effects on extracorporeal HepG2 cells under different temperatures, pressures of permeability and lengths of treatment time. Method: According to different temperatures, pressures of permeability and lengths of treating time, extracorporeal HepG2 cells of human hepatoma cell-line were grouped to 80 groups. Cell index (CI) as the measurement of killing effect were calculated by monotetrazolium (MTT) methods, i.e., CI =1- (the OD value in treated group - the OD value in blank control group) / (mean of untreated control group - mean of blank control group). According to the factorial design, data were fed into SPSS 10.0 and analyzed by three-way ANOVA (analysis of variance). Result: Temperature, pressure of permeability and length of treating time all had effects on the CI (cell index) level. Length of treating time was the most influential factor of the three. Additionally, any two of them all had statistically significant interactive effects on the CI level. When treated for 5-30 min, destilled water at $46^{\circ}C$ stably generated the highest CI. Conclusion: The "$46^{\circ}C$-destilled water-60 min" was considered as the optimal combination of conditions which lead to highest CI. We suggest exerting celiac lavage for 15 min with stilled water at $40^{\circ}C-43^{\circ}C$ in surgical practice as a hyperthermia treatment to achieve ideal killing effects on free cancer cells, which is feasible, practical, and clinically effective.

• Journal of Korean Foot and Ankle Society
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• v.6 no.2
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• pp.139-143
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• 2002

Purpose: We analyzed the Metatarso-Phalangeal Oblique Angle(MPOA) of Diabetic foot. Materials and methods: We studied retrospectively 60 cases of diabetic foot in 52 patients, for the evaluation of the correlations between clinical outcomes and radiologic findings in the conservative management group (Group A; 36 cases) and the major operation group (Group B; 24 cases). We measured MPOA on AP view. The MPOA was defined as the intersection angle of the Metatarso-Phalangeal Break Line (a line passing from the second to fifth metatarsal heads) and the long axis of foot in sagittal plane. We performed the statistical analysis between MPOA and clinical outcomes. by independent t-test. Results: The mean of MPOA in group B, $70.79^{\circ}$ (range: $62.8^{\circ}-81.3^{\circ}$), was significantly higher than that in group A, $68.04^{\circ}$ (range: $62.0^{\circ}-76.4^{\circ}$). The mean of MPOA in patients of fore foot lesions(30 cases), $71.30^{\circ}$ (range: $62.0^{\circ}-71.5^{\circ}$), was significantly higher than that in patients of hind foot lesions(30 cases), $66.97^{\circ}$(range: $62.8^{\circ}-81.3^{\circ}$). Conclusions: We recognized the MPOA might be useful simple parameter in assessing the diabetic foot.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.380-385
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• 2006

In this paper, a program that can be utilized to measure and analyze radio propagation characteristics is developed. This program is able to control the measurement instruments including spectrum analyzer through GPIB interface and analyze the measured data to yield mean excess delay and RMS delay spread. The measured path loss can be compared with theoretical value in free space or inside a tunnel. The measured and analyzed results can also be presented in the forms of graphs. As these tasks can be conducted on the spot of the measurements, this program is very helpful in performing and verifying the measurements immediately. In this thesis radio propagation characteristics with frequency bands of 2.45 and 5.8GHz in subway tunnels are measured by using the program. Path loss and delay spread in subway tunnel is measured and compared according to the form of antenna beam and LOS(Line of Sight) and N-LOS(Non-Line of Sight).