Maintenance of adequate soil water potential during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil water movement within and below the rooting zone can facilitate optimal irrigation scheduling aimed at minimizing the adverse effects of water stress on crop growth and development and the leaching of water below the root zone which can have adverse environmental effects. The objective of this study was to evaluate the feasibility of using a portable irrigation controller with an Watermark sensor for the cultivation of drip-irrigated vegetable crops in a greenhouse. The control capability of the irrigation controller for a soil water potential of -20 kPa was evaluated under summer conditions by cultivating 45-day-old tomato plants grown in three differently textured soils (sandy loam, loam, and loamy sands). Water contents through each soil profile were continuously monitored using three Sentek probes, each consisting of three capacitance sensors at 10, 20, and 30 cm depths. Even though a repeatable cycling of soil water potential occurred for the potential treatment, the lower limit of the Watermark (about 0 kPa) obtained in this study presented a limitation of using the Watermark sensor for optimal irrigation of tomato plants where -20 kPa was used as a point for triggering irrigations. This problem might be related to the slow response time and inadequate soil-sensor interface of the Watermark sensor as compared to a porous and ceramic cup-based tensiometer with a sensitive pressure transducer. In addition, the irrigation time of 50 to 60 min at each of the irrigation operation gave a rapid drop of the potential to zero, resulting in over irrigation of tomatoes. There were differences in water content among the three different soil types under the variable rate irrigation, showing a range of water contents of 16 to 24%, 17 to 28%, and 24 to 32% for loamy sand, sandy loam, and loam soils, respectively. The greatest rate increase in water content was observed in the top of 10 cm depth of sandy loam soil within almost 60 min from the start of irrigation.
In this study, the
Variables influencing the free face movement due to rock blasting include the physical and mechanical properties, in particular the discontinuity characteristics, explosive type, charge weight, burden, blast-hole spacing, delay time between blast-holes or rows, stemming conditions. These variables also affects the blast vibration, air blast and size of fragmentation. For the design of surface blasting, the priority is given to the safety of nearby buildings. Therefore, blast vibration has to be controlled by analyzing the free face movement at the surface blasting sites and also blasting operation needs to be optimized to improve the fragmentation size. High-speed digital image analysis enables the analyses of the initial movement of free face of rock, stemming optimality, fragment trajectory, face movement direction and velocity as well as the optimal detonator initiation system. Even though The high-speed image analysis technique has been widely used in foreign countries, its applications can hardly be found in Korea. This thesis aims at carrying out a fundamental study for optimizing the blast design and evaluation using the high-speed digital image analysis. A series of experimentation were performed at two large surface blasting sites with the rock type of shale and granite, respectively. Emulsion and ANFO were the explosives used for the study. Based on the digital images analysis, displacement and velocity of the free face were scrutinized along with the analysis fragment size distribution. In addition, AUTODYN, 2-D FEM model, was applied to simulate detonation pressure, detonation velocity, response time for the initiation of the free face movement and face movement shape. The result show that regardless of the rock type, due to the displacement and the movement velocity have the maximum near the center of charged section the free face becomes curved like a bow. Compared with ANFO, the cases with Emulsion result in larger detonation pressure and velocity and faster reaction for the displacement initiation.
The purpose of this study is to examine the quality characteristics of lamb stock by different salt contents in it. For this purpose, mechanical tests (color value, pH, sugar content, salinity, amino-acid content) and sensory evaluation (attribute difference test & acceptance) were conducted, showing the following results; Salinity and sugar increased significantly (p<0.01, p<0.001) with salt contents increased. The 0.1% salt addition group contained 32 kinds of free amino-acids, while 0.2% and 0.3% contained 34. 0.4% salt addition group turned out to contain 34 kinds of free amino-acid in it. The amount of the free amino-acid content was also the highest with 0.3% sample group, followed by 0.2%, 0.4%, and 0.1% sample group. In the test group, 9 kinds of essential amino-acid were discovered, and all samples contained histidine and arginine, which were essential in the growth of children. Among all samples, arginine appeared to be the highest in content. Each of the essential amino-acid content varied with statistical significance among the sample groups. In addition, 14 kinds of amino-acids other than the above mentioned were discovered, as well. The 0.3% salt addition group showed the highest 'after taste' value, and the differences among the sample groups were statistically significant(p<0.001). The acceptance test of the lamb stock showed that the flavor and mouth feel did not vary among the sample groups with statistical significance. The control group had the highest value for appearance, measuring scoring 4.32, and the sample group of 0.2% salt addition showed the lowest value of appearance, scoring 3.63. As for the preference on the taste, the highest value of 4.09 came from the 0.3% salt addition group. The differences between the sample groups were statistically significant. Finally, with regard to the overall quality, the 0.3% salt addition group had the highest value of 4.23 while the control group scored the lowest, 3.52. The differences among the samples were statistically significant. The overall result of the study indicated that the optimal rate of salt addition in making lamb stock was 0.3%.
Background: In this study, we investigated the risk factors for the development or progression of aortic regurgitation(AR) in patients with type I ventricular septal defect (VSD) to determine the optimal surgical timing and strategy. Material and Method: Three-hundred and ten patients with type I VSD with or without AR were included. The mean of age was 73.7
Kaolinite [
This is a study on the optimized dispensing of the auto dispenser used for the purpose of reducing the exposure dose and accurate radiation dose of radioisotope with regard to the PET/CT practitioners. The research method was to find the optimized dispensing method through evaluating the results according to the syringe type, dispensing rate, and vial pressure and through the application of corrected values. As a result of this study, 9.38 mCi has been dispensed on average in the case of 5 ml syringe, and the reproducibility close to 10 mCi was shown at the dispense of 9.55 mCi in the case of 3 ml syringe. In the evaluation according to the dispensing rate, the quantity of radioisotope close to 10 mCi was dispensed at the rate of 5 mm/min when the measurement was carried out by increasing the rate by 5 mm/min units in the order of 5, 10, 15 and 20 mm/min. In the evaluation result according to the vial pressure before/after the use of Needle filter, it was measured to be 9.53 mCi before use and 9.84 mCi after use confirming that the dispensing after using Needle filter showed the optimal value. In addition, in the evaluation of radioactivity before/after the application of corrected values according to the increase in dispense frequency, it was measured 9.53 mCi before correction and 10.07 mCi after correction confirming that the value with correction applied was closer to the quantitative value. Thus, a good optimized method was confirmed to use a 3 ml syringe with dispensing rate of 5 mm/min, to use a Needle filter at dispensing, and to set the corrected value of [
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70
The use of CCA as a wood preservative was recently inhibited due to its environmental pollution and human harmfulness. Instead of CCA, copper azole (CuAz) and alkaline copper quaternary (ACQ) have been used as alternative wood preservatives, but the price of the preservatives is much more expensive than that of CCA. As a substitute for high-priced CuAz and ACQ, environmentally friendly wood preservatives were formulated with okara, which is an organic waste from the production of tofu. Prior to formulating the preservatives, okara was hydrolyzed by three levels of sulfuric acid concentration (1, 2.5 and 5%) to easily penetrate the effective components of the preservatives into wood blocks. Final preservative solutions were formulated with the hydrolyzed okara and metal salts, such as copper sulfate, copper chloride and borax. The preservatives were treated into wood blocks by vacuum-pressure method to measure the treatability of the preservatives, and the treated wood blocks were placed in hot water for three days to measure the leachability of the preservatives. The effective components of the preservatives might be successfully penetrated into wood blocks through the uses of hydrolyzed okara and ammonia water. However, the leached amount of effective components was increased as the concentration of acid used for the hydrolysis of okara increased. The treatability and leachability of the preservatives were not affected by hydrolysis temperature but negatively affected by the addition of borax. Based on the results above, the optimal conditions for formulating okara-based wood preservatives cost-effectively and environmentally might be 1% acid hydrolysis of okara and the use of