• Transactions of Materials Processing
• /
• v.19 no.1
• /
• pp.11-16
• /
• 2010

The influence of pre-strain on low cycle fatigue behavior of Fe-18Mn-0.05Al-0.6C TWIP steel was studied by conducting axial strain-controlled tests. As-received plates were deformed by rolling with reduction ratios of 10 and 30%, respectively. A triangular waveform with a constant frequency of 1 Hz was employed for low cycle fatigue test at the total strain amplitudes in the range of ${\pm}0.4\;{\sim}\;{\pm}0.6$ pct. The results showed that low-cycle fatigue life was strongly dependent on the amount of pre-strain as well as the strain amplitude. Increasing the amount of prestrain, the number of reversals to failure was significantly decreased at high strain amplitudes, but the effect was negligible at low strain amplitudes. A new model for predicting fatigue life of pre-strained body has been suggested by adding ${\Delta}E_{pre-strain}$ to the energy-based fatigue damage parameter. Also, high-cycle fatigue lives predicted using the low-cycle fatigue data well agreed with the experimental ones.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.1
• /
• pp.131-136
• /
• 2013

TSV based 3D ICs have been widely developed with new problems at die and IC levels. It is imperative to test at post-bond as well as pre-bond to achieve high reliability and yield. This paper introduces a new testable design technique which not only test microscopic defects at TSV input/output contact at a die but also test interconnect defects at a stacked IC. IEEE 1500 wrapper cells are augmented and through at-speed tests for pre-bond die and post-bond IC, known-good-die and defect free 3D IC can be massively manufactured+.

• Asian Oncology Nursing
• /
• v.12 no.1
• /
• pp.110-116
• /
• 2012

Purpose: This study was performed to identify the pre-and post-transplant nutritional assessment for patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Methods: The subjects of this study were 25 patients undergoing allogeneic HSCT. The data collection was performed from January 31st to March 31st, 2011. The Patient-Generated Subjective Global Assessment (PG-SGA), anthropometrics and biochemical test were collected from the time they entered the isolation unit until they left. Results: Pre-transplant nutritional assessment status indicated moderate malnutrition which scored $7.32{\pm}1.68$ in PG-SGA. There were 22 patients (88.0%) with moderate malnutrition and 3 patients (12.0%) with severe malnutrition. Post-transplant nutritional assessment indicated severe malnutrition status which scored $11.92{\pm}3.26$ in PG-SGA. Pre-and post-transplant nutritional assessment displayed significant differences (p<.001) in PG-SGA score. Hematopoietic stem cell transplantation led to a deterioration of patients' nutritional status. Pre-transplant patients were already in malnutrition status and patients undergoing allogeneic HSCT were at risk for malnutrition. Conclusion: Pre-and post-transplant patients were categorized as having undernutritional and malnutritional status. Pre-transplant nutrition status impacted on post-transplant nutritional status. Health care personnel should pay attention to patient's nutrition status when undergoing allogeneic HSCT with appropriate nutritional assessment tools.

• Journal of Veterinary Clinics
• /
• v.4 no.2
• /
• pp.483-490
• /
• 1987

In order to study the compensatory renal function in 6 Korean black goats with 75% reduction in renal mass, some blood chemical values were determined and pathological changes were examined. The results were as follows : 1. BUN level increased significantly from post-operation day 1 through day 30(p<0.01) compared with pre-operation level. Serum creatinine level increased significantly from post-operation day 1 through day 26(p <0.01 ) compared with pre-operation level and remained higher than pre-operation level at day 30(p <0. 05). 2. Serum calcium level increased significantly from post-operation day 4 through day 7(p<0.01) compared with pre-operation level and remained higher than pre-operation level from post-operation day 8 through day 14(p<0.05). Serum phosphorus level decreased at postoperation day 4,5(p<0.05 ) compared with pre-operation level. 3. RBC counts decreased at post-operation day 2. 3, 5. to 30(p<0.05), PCV decreased at post-operation day 2, 3, 5, 7, to 30(p<0.05), hemoglobin level decreased at post-operation day 2, 8, 14, to 30(p<0.05), compared with pre - operation levels, respectively. 4. The ventral half of the right kidney was infarcted by the ligation of ventral branch of right renal artery.

• The KSFM Journal of Fluid Machinery
• /
• v.20 no.1
• /
• pp.21-28
• /
• 2017

Optimization process of pre-swirl nozzle geometry was conducted to improve the discharge coefficient of pre-swirl system by using CFD. The optimization of pre-swirl nozzle shape covered the converging angle and the location of the converging nozzle. Optimization process included Optimal Latin Hyper-cube Design method to get the experimental points and the Kriging method to create the response surface which gives candidate points. The process was finished when the difference between the predicted value and CFD value of candidate point was less than 0.1 %. This paper compared the Reference model, Initial model which is the first model of optimization and Optimized model to study flow characteristics. Finally, the discharge coefficient of Optimized model is improved about 17 % to the Reference model.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.63 no.5
• /
• pp.676-682
• /
• 2014

In this paper, precipitation echo(PRE) and non-precipitaion echo(N-PRE)(including ground echo and clear echo) through weather radar data are identified with the aid of neuro-fuzzy algorithm. The accuracy of the radar information is lowered because meteorological radar data is mixed with the PRE and N-PRE. So this problem is resolved by using RBFNN and judgement module. Structure expression of weather radar data are analyzed in order to classify PRE and N-PRE. Input variables such as Standard deviation of reflectivity(SDZ), Vertical gradient of reflectivity(VGZ), Spin change(SPN), Frequency(FR), cumulation reflectivity during 1 hour(1hDZ), and cumulation reflectivity during 2 hour(2hDZ) are made by using weather radar data and then each characteristic of input variable is analyzed. Input data is built up from the selected input variables among these input variables, which have a critical effect on the classification between PRE and N-PRE. Echo judgment module is developed to do echo classification between PRE and N-PRE by using testing dataset. Polynomial-based radial basis function neural networks(RBFNNs) are used as neuro-fuzzy algorithm, and the proposed neuro-fuzzy echo pattern classifier is designed by combining RBFNN with echo judgement module. Finally, the results of the proposed classifier are compared with both CZ and DZ, as well as QC data, and analyzed from the view point of output performance.

• Journal of Korean Society of Transportation
• /
• v.27 no.1
• /
• pp.43-51
• /
• 2009

This paper investigates the accuracy of vehicle pre-braking speed estimates based upon tire/roadway coefficient of friction (drag factor) measurements and skid mark measurements Data for pre-braking and pre-skidding speeds were collected to determine if there were any correlations between pre-braking speeds and pre-skidding speeds. Braking tests were performed on two vehicles using various measurement devices including a fifth wheel, a speed gun, and a vericom 2000. The vehicle speeds, braking distances, skid mark distances, and deceleration histories were recorded. From these data. coefficients of friction and vehicle pre-skidding speeds for the tested road surface were calculated. The pre-skidding speeds were then compared to the actual pre-braking speeds of the vehicles in order to establish relationships between pre-skidding and pre-braking speed. A correlation between the Pre-skidding speed and the actual pre-braking speed was established for the study data.

• Journal of Satellite, Information and Communications
• /
• v.6 no.2
• /
• pp.20-25
• /
• 2011

The authors have proposed novel TDD-CDMA systems with Pre-Rake transmit diversity schemes (system 1 and system 2) using multiple transmit antennas in [2] and have also evaluated the system performance through the theoretical analysis and computer simulation. However, the performance of system 2 which transmit a signal using all antennas has not been evaluated for multi-user environment. Therefore in this paper, we analyze the performance of system 2 for multi-user environment and compare the performance with that of the already proposed system 1 which chooses only one antenna. From the numerical results, it is found that system 2 outperforms system 1 as the number of users increases while system 1 outperforms system 2 at a small number of users. Therefore in order to achieve the best system performance, the Pre-Rake transmit diversity type should be selected at the base station according to the number of users.

• Analytical Science and Technology
• /
• v.35 no.3
• /
• pp.129-135
• /
• 2022

We tested the pre-treatment of alumina, leucine, alumina mixed with leucine at ratios of 9:1 (Al-Leu (9:1)) and 5:1 (Al-Leu (5:1)), and alumina mixed with sodium lactate at a ratio of 5:1 (Al-Lac (5:1)) on aged fingerprints (1, 7, 14, and 30 days after natural fingerprinting) before cyanoacrylate (CA) fuming to improve the development efficacy. As a result of the experiment, fingerprints with pre-treatment of alumina, leucine, Al-Leu (9:1), Al-Leu (5:1), and Al-Lac (5:1) showed better development efficacy (area and minutiae) than fingerprints without pre-treatment. Therefore, this modified CA fuming method improved the development efficacy with five pretreatments.

• Journal of Information Technology Applications and Management
• /
• v.15 no.2
• /
• pp.33-49
• /
• 2008

The purpose of this study is to find student factors associated with the students' evaluation of university teaching, and to provide a meaningful reference to policy-making of teaching evaluation. Based on the surveyed questionnaires from 232 students who participated in e-learning course. in combination with applying descriptive statistics, this study analyzes (1) the influences of students' pre-motivation level of student based-on ARCS theory on class satisfaction, (2) the influences of students' grade, attendance, and class involvement on class satisfaction, and (3) the influences of e-learning experience on students' pre-motivation level and class satisfaction. Result of this study shows that: (1) students' pre-motivation level including Attention(A), Relevance(R), Confidence(C), and Satisfaction(S) is positively correlated to students' evaluation for teaching, (2) students' grade, attendance. and class involvement are positively correlated to students' evaluation for teaching, and (3) students' e-learning experience is not related with students' pre-motivation level, whereas it is related with class satisfaction.