• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.166-184
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• 1979

In order to prevent the water loss in the irrigation canal constructed on the sandy gravel layer or on the other highly permeable ground layer, lining has been practiced. Many studies have been done so far on the lining method to prevent the water loss in the irrigation canal and recently studies on the lining with plastic film or polyethylene film were also reported. However, the plastic film or polyethylene film has low strength and is liable to break, and water loss from pin hole caused by contacting with sand or gravel is highly predicted. This study was then conducted to find proper lining and buring method in canal construction of polypropylene mat after coated with vinyl, as one way to overcome the shortcoming frequently observed when plastic or usual polyehtylene film were used. Eventhough rather longer periods of experiments are needed to attain reliable and accurate results on the variation of durability, the durability of asphalt coated area, or on the damage due to freeze after burial or exposure of polypropylene mat, the experiemental results obtained during one year of period are summarized as follows: 1. The curvature at the area between canal bottom and side slope had increased stability and saved consruction cost. The relationship among the variation of curvature, the reduction of polypropylene mat and the reduced amount of soil cutting at each side slope was presented in Fig. 7 through 9. 2. The depth of covering material to protect polypropylene mat was desired to be over 30cm, considering the water depth, side slope, canal cleaning practices, traffic, or back pressure of irrigation period. 3. In order to increase the canal stability and to prevent slope erosion, sandy soil was required, to be placed under ground, and coarse gravel should cover the surface area of canal. 4. The studies on the stability of side slope in the canal should consider the passive area on the bottom and the slope should be about 1 to 2, considering the slope stability, allowable velocity and tractive force. 5. When compared with earth lining, the lining with polypropylene mat coated with vinyl was responsible to save 28% and 37% of canal lining cost, when the soil carrying distances were 500 and 700m. respectively. 6. The water interception was almost completely attained when the polypropylene mat coated with vinyl was used for lining. But further studies were assumed to be necessary for the use of asphalt since the strength of polypropylene mat connected with asphalt will vary with duration.

• Tuberculosis and Respiratory Diseases
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• v.54 no.1
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• pp.71-79
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• 2003

Background : A bronchoalveolar lavage(BAL) is useful in diagnosing the etiology of bilateral pulmonary infiltrations, but may worsen the oxygenation and clinical status in severely hypoxemic patients. This study assessed the safety and efficacy of the continuous positive airway pressure(CPAP) using a conventional mechanical ventilator via a face mask as a tool for maintaining the oxygenation level during BAL. Methods : Seven consecutive patients with the bilateral pulmonary infiltrates and severe hypoxemia ($PaO_2/FIO_2$ ratio ${\leq}200$ on oxygen 10 L/min via mask with reservoir bag) were enrolled. The CPAP 5-6 $cmH_2O(F_IO_2\;1.0)$ was delivered through an inflatable face mask using a conventional mechanical ventilator. The CPAP began 10 min before starting the BAL and continued for 30 min after the procedure was completed. A bronchoscope was passed through a T-adapter and advanced through the mouth. BAL was performed using the conventional method. The vital signs, pulse oxymetry values, and arterial blood gases were monitored during the study. Results : (1) Median age was 56 years(male:female=4:3). (2) The baseline $PaO_2$ was $78{\pm}16mmHg$, which increased significantly to $269{\pm}116mmHg$(p=0.018) with CPAP. After the BAL, the $PaO_2$ did not decrease significantly but returned to the baseline level after the CPAP was discontinued. The $SpO_2$ showed a similar trend with the $PaO_2$ and did not decrease to below 90 % during the duration of the study. (3) The $PaCO_2$ increased and the pH decreased significantly after the BAL but returned to the baseline level within 30 min after the BAL. (5) No complications directly related to the BAL procedure were encountered. However, intubation was necessary in 3 patients(43 %) due to the progression of the underlying diseases. Conclusion : In severe hypoxemic patients, CPAP using a face mask and conventional mechanical ventilator during a BAL might allow minimal alterations in oxygenation and prevent subsequent respiratory failure.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.589-600
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• 2007

Recently, with the rapid expansion of the franchise restaurants, ensuring food safety has become essential for restaurant growth. Consequently, the need for food safety training and related material is in increasing demand. In this study, we identified potentially hazardous risk factors for ensuring food safety in restaurants through a food safety monitoring tool, and developed training materials for restaurant employees based on the results. The surveyed restaurants, consisting of 6 Korean restaurants and 1 Japanese restaurant were located in Seoul. Their average check was 15,500 won, ranging from 9,000 to 23,000 won. The range of their total space was 297.5 to $1322.4m^2$, and the amount of kitchen space per total area ranged from 4.4 to 30 percent. The mean score for food safety management performance was 57 out of 100 points, with a range of 51 to 73 points. For risk factor analysis, the most frequently cited sanitary violations involved the handwashing methods/handwashing facilities supplies (7.5%), receiving activities (7.5%), checking and recording of frozen/refrigerated foods temperature (0%), holding foods off the floor (0%), washing of fruits and vegetables (42%), planning and supervising facility cleaning and maintaining programs of facilities (50%), pest control (13%), and toilet equipped/cleaned (13%). Base on these results, the main points that were addressed in the hygiene training of restaurant employees included 4 principles and 8 concepts. The four principles consisted of personal hygiene, prevention of food contamination, time/temperature control, and refrigerator storage. The eight concepts included: (1) personal hygiene and cleanliness with proper handwashing, (2) approved food source and receiving management (3) refrigerator and freezer control, (4) storage management, (5) labeling, (6) prevention of food contamination, (7) cooking and reheating control, and (8) cleaning, sanitation, and plumbing control. Finally, a hygiene training manual and poster leaflets were developed as a food safety training materials for restaurants employees.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1018-1027
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• 2005

The purpose of this study was to investigate nutrients intake and health-related behaviors in elderly people residing in Gyeongsan-si, Gyeongbuk who have no problem in daily living. Information on general characteristics of the elderly, health-related behaviors and dietary habits were obtained by interview based on questionnare. Dietary nutrients intake data were obtained through the 24 recall method. The subject group of this study was composed of 113 males and 112 females, the average age being $73.1\pm6.06$ years old. In health related factors, $76.9\%$ of subjects exercised regularly. The rates of alcohol drinking and smoking showed to be $38.2\%\;and\;22.2\%$, respectively. There were many elderly with neuralgia, hypertension, and gastrointestinal disease, especially female were worse. Average heights of the subjects were lower than the standard established in the Korean Recommended Dietary Allowances, and average weights were similar to the standards. The mean BMI and WHR were 24.8 (male 23.7, female 25.7) and 0.92 (male 0.92, female 0.89), respectively. Most of the subjects had a regular meal pattern comsuming three meals a day, and many elderly, especially more than $79.5\%$ of female, prepared the meals for themselves. Mean daily energy intakes and RDA percentage of energy intakes of the male and female subjects were estimated as 1426.9kcal $(79.3\%)$ and 1381.3 kcal $(86.3\%)$, respectively. Mean daily intakes of nutrients were estimatied as 48.1g for protein, 411.3mg for calcium, 8.05mg for iron, 541.8 R.E. for vitamin A, 0.84mg for vitamin $B_1$, and 0.79mg for vitamin $B_2$. Most nutrients except protein, clacium, iron and vitamin $B_2$ were consumed over $75\%$ of the RDA. Female elderly showed significant lower intakes (p<0.05) for most of the nutrients except calcium, phosphorus and vitamin ethan the elderly male.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.392-400
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• 2007

This experiment was conducted to evaluate effects of various periods of rye silage feeding on the growth performance, blood characteristics, and carcass quality of finishing pigs. A total of sixteen [($Landrace{\times}Yorkshire{\times}Duroc$)] pigs (90.26 kg in average initial body weight) were tested in individual cages for a 30 day period. Dietary treatments included 1) CON (basal diet), 2) S10 (basal diet for 20 days and 3% rye silage for 10 days) 3) S20 (basal diet for 10 days and 3% rye silage for 20 days) and 4) S30 (3% rye silage for 30 days). There were no significant differences in the ADG and gain/feed ratio among the treatments(p>0.05), however the ADFI was higher in pigs fed the CON diet than with pigs fed diets with rye silage (p<0.05). The DM digestibility was higher with the S20 diet than with the S30 diet (p<0.05). With regard to blood characteristics, pigs fed rye silage had a significantly reduced cortisol concentration compared to pigs fed the CON diet (p<0.05). The backfat thickness was higher with the CON diet than with the S20 or S30 diets (p<0.05). Regarding the fatty acid contents of the leans, the C18:0 and total SFA were significantly higher with the CON diet than with the other diets (p<0.05). However, the C18:1n9, total MUFA and UFA/SFA levels were significantly lower with the CON diet than the other diets (p<0.05). Regarding the fatty acid contents of fat, the levels of C18:1n9 and MUFA were similar with the S20 and S30 diets, however, these levels were higher than with the CON or S10 diets (p<0.05). In conclusion, feed intake and DM digestibility were affected by rye silage, and the cortisol concentration, backfat thickness and fatty acid composition of pork were positively affected by feeding pigs rye silage.

• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.161-167
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• 2018

Purpose : This study evaluates the usefulness of the Modified Hybrid-VMAT scheme with consideration of background radiation when establishing a treatment plan for multiple bone metastatic cancer including multiple tumors on the same axis. Materials and Methods : The subjects of this study consisted of five patients with multiple bone metastatic cancer on the same axis. The planning target volume(PTV) prescription dose was 30 Gy, and the treatment plan was established using Ray Station(Ray station, 5.0.2.35, Sweden). In the treatment plan for each patient, two or more tumors were set as one isocenter. A volumetric modulated arc therapy(VMAT) plan, a hybrid VMAT(h) plan with no consideration of background radiation, and a modified hybrid VMAT(mh) with consideration of background radiation were established. Then, using each dose volume histogram(DVH), the PTV maximum dose($D_{max}$), mean dose($D_{mean}$), conformity index(CI), and homogeneity index(HI) were compared among the plans. In addition, the organ at risk(OAR) of each treatment site was evaluated, and the total MU(Monitor Unit) and treatment time were also analyzed. Results : The PTV $D_{max}$ values of VMAT, VMAT(h) and VMAT(mh) were 3188.33 cGy, 3526 cGy, and 3285.67 cGy, the $D_{mean}$ values were 3081 cGy, 3252 cGy, and 3094 cGy; the CI values were $1.35{\pm}0.19$, $1.43{\pm}0.12$, and $1.30{\pm}0.06$; the HI values were $1.06{\pm}0.01$, $1.14{\pm}0.06$, and $1.09{\pm}0.02$; and the VMAT(h) OAR value was increased 3 %, and VMAT(mh) OAR value was decreased 18 %, respectively. Furthermore, the mean MU values were 904.90, 911.73, and 1202.13, and the mean beam on times were $128.67{\pm}10.97$, $167.33{\pm}7.57$, and $190.33{\pm}4.51$ respectively. Conclusions : Applying Modified Hybrid-VMAT when treating multiple targets can prevent overdose by correcting the overlapping of doses. Furthermore, it is possible to establish a treatment plan that can protect surrounding normal organs more effectively while satisfying the inclusion of PTV dose. Long-term follow-up of many patients is necessary to confirm the clinical efficacy of Modified Hybrid-VMAT.

• Journal of Intelligence and Information Systems
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• v.26 no.4
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• pp.173-198
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• 2020

For a long time, many studies have been conducted on predicting the success of campaigns for customers in academia, and prediction models applying various techniques are still being studied. Recently, as campaign channels have been expanded in various ways due to the rapid revitalization of online, various types of campaigns are being carried out by companies at a level that cannot be compared to the past. However, customers tend to perceive it as spam as the fatigue of campaigns due to duplicate exposure increases. Also, from a corporate standpoint, there is a problem that the effectiveness of the campaign itself is decreasing, such as increasing the cost of investing in the campaign, which leads to the low actual campaign success rate. Accordingly, various studies are ongoing to improve the effectiveness of the campaign in practice. This campaign system has the ultimate purpose to increase the success rate of various campaigns by collecting and analyzing various data related to customers and using them for campaigns. In particular, recent attempts to make various predictions related to the response of campaigns using machine learning have been made. It is very important to select appropriate features due to the various features of campaign data. If all of the input data are used in the process of classifying a large amount of data, it takes a lot of learning time as the classification class expands, so the minimum input data set must be extracted and used from the entire data. In addition, when a trained model is generated by using too many features, prediction accuracy may be degraded due to overfitting or correlation between features. Therefore, in order to improve accuracy, a feature selection technique that removes features close to noise should be applied, and feature selection is a necessary process in order to analyze a high-dimensional data set. Among the greedy algorithms, SFS (Sequential Forward Selection), SBS (Sequential Backward Selection), SFFS (Sequential Floating Forward Selection), etc. are widely used as traditional feature selection techniques. It is also true that if there are many risks and many features, there is a limitation in that the performance for classification prediction is poor and it takes a lot of learning time. Therefore, in this study, we propose an improved feature selection algorithm to enhance the effectiveness of the existing campaign. The purpose of this study is to improve the existing SFFS sequential method in the process of searching for feature subsets that are the basis for improving machine learning model performance using statistical characteristics of the data to be processed in the campaign system. Through this, features that have a lot of influence on performance are first derived, features that have a negative effect are removed, and then the sequential method is applied to increase the efficiency for search performance and to apply an improved algorithm to enable generalized prediction. Through this, it was confirmed that the proposed model showed better search and prediction performance than the traditional greed algorithm. Compared with the original data set, greed algorithm, genetic algorithm (GA), and recursive feature elimination (RFE), the campaign success prediction was higher. In addition, when performing campaign success prediction, the improved feature selection algorithm was found to be helpful in analyzing and interpreting the prediction results by providing the importance of the derived features. This is important features such as age, customer rating, and sales, which were previously known statistically. Unlike the previous campaign planners, features such as the combined product name, average 3-month data consumption rate, and the last 3-month wireless data usage were unexpectedly selected as important features for the campaign response, which they rarely used to select campaign targets. It was confirmed that base attributes can also be very important features depending on the type of campaign. Through this, it is possible to analyze and understand the important characteristics of each campaign type.

• The Journal of Korean Society for Radiation Therapy
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• v.32
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• pp.17-29
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• 2020

Purpose: The purpose of this work was to investigate the dosimetric impact of mixed energy partial arc technique on prostate cancer VMAT. Materials and Methods: This study involved prostate only patients planned with 70Gy in 30 fractions to the planning target volume (PTV). Femoral heads, Bladder and Rectum were considered as oragan at risk (OARs). For this study, mixed energy partial arcs (MEPA) were generated with gantry angle set to 180°~230°, 310°~50° for 6MV arc and 130°~50°, 310°~230° for 15MV arc. Each arc set the avoidance sector which is gantry angle 230°~310°, 50°~130° at first arc and 50°~310° at second arc. After that, two plans were summed and were analyzed the dosimetry parameter of each structure such as Maximum dose, Mean dose, D2%, Homogeneity index (HI) and Conformity Index (CI) for PTV and Maximum dose, Mean dose, V70Gy, V50Gy, V30Gy, and V20Gy for OARs and Monitor Unit (MU) with 6MV 1 ARC, 6MV, 10MV, 15MV 2 ARC plan. Results: In MEPA, the maximum dose, mean dose and D2% were lower than 6MV 1 ARC plan(p<0.0005). However, the average difference of maximum dose was 0.24%, 0.39%, 0.60% (p<0.450, 0.321, 0.139) higher than 6MV, 10MV, 15MV 2 ARC plan, respectively and D2% was 0.42%, 0.49%, 0.59% (p<0.073, 0.087, 0.033) higher than compared plans. The average difference of mean dose was 0.09% lower than 10MV 2 ARC plan, but it is 0.27%, 0.12% (p<0.184, 0.521) higher than 6MV 2 ARC, 15MV 2 ARC plan, respectively. HI was 0.064±0.006 which is the lowest value (p<0.005, 0.357, 0.273, 0.801) among the all plans. For CI, there was no significant differences which were 1.12±0.038 in MEPA, 1.12±0.036, 1.11±0.024, 1.11±0.030, 1.12±0.027 in 6MV 1 ARC, 6MV, 10MV, 15MV 2 ARC, respectively. MEPA produced significantly lower rectum dose. Especially, V70Gy, V50Gy, V30Gy, V20Gy were 3.40, 16.79, 37.86, 48.09 that were lower than other plans. For bladder dose, V30Gy, V20Gy were lower than other plans. However, the mean dose of both femoral head were 9.69±2.93, 9.88±2.5 which were 2.8Gy~3.28Gy higher than other plans. The mean MU of MEPA were 19.53% lower than 6MV 1 ARC, 5.7% lower than 10MV 2 ARC respectively. Conclusion: This study for prostate radiotherapy demonstrated that a choice of MEPA VMAT has the potential to minimize doses to OARs and improve homogeneity to PTV at the expense of a moderate increase in maximum and mean dose to the femoral heads.

• Journal of Chest Surgery
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• v.39 no.12 s.269
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• pp.879-890
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• 2006

Background: The dysfunction of multiple organs is found to be caused by reactive oxygen species as a major modulator of microvascular injury after hemorrhagic shock. Hemorrhagic shock, one of many causes inducing acute lung injury, is associated with increase in alveolocapillary permeability and characterized by edema, neutrophil infiltration, and hemorrhage in the interstitial and alveolar space. Aggressive and rapid fluid resuscitation potentially might increased the risk of pulmonary dysfunction by the interstitial edema. Therefore, in order to improve the pulmonary dysfunction induced by hemorrhagic shock, the present study was attempted to investigate how to reduce the inflammatory responses and edema in lung. Material and Method: Male Sprague-Dawley rats, weight 300 to 350 gm were anesthetized with ketamine(7 mg/kg) intramuscular Hemorrhagic Shock(HS) was induced by withdrawal of 3 mL/100 g over 10 min. through right jugular vein. Mean arterial pressure was then maintained at $35{\sim}40$ mmHg by further blood withdrawal. At 60 min. after HS, the shed blood and Ringer's solution or 5% albumin was infused to restore mean carotid arterial pressure over 80 mmHg. Rats were divided into three groups according to rectal temperature level($37^{\circ}C$[normothermia] vs $33^{\circ}C$[mild hypothermia]) and resuscitation fluid(lactate Ringer's solution vs 5% albumin solution). Group I consisted of rats with the normothermia and lactate Ringer's solution infusion. Group II consisted of rats with the systemic hypothermia and lactate Ringer's solution infusion. Group III consisted of rats with the systemic hypothermia and 5% albumin solution infusion. Hemodynamic parameters(heart rate, mean carotid arterial pressure), metabolism, and pulmonary tissue damage were observed for 4 hours. Result: In all experimental groups including 6 rats in group I, totally 26 rats were alive in 3rd stage. However, bleeding volume of group I in first stage was $3.2{\pm}0.5$ mL/100 g less than those of group II($3.9{\pm}0.8$ mL/100 g) and group III($4.1{\pm}0.7$ mL/100 g). Fluid volume infused in 2nd stage was $28.6{\pm}6.0$ mL(group I), $20.6{\pm}4.0$ mL(group II) and $14.7{\pm}2.7$ mL(group III), retrospectively in which there was statistically a significance between all groups(p<0.05). Plasma potassium level was markedly elevated in comparison with other groups(II and III), whereas glucose level was obviously reduced in 2nd stage of group I. Level of interleukine-8 in group I was obviously higher than that of group II or III(p<0.05). They were $1.834{\pm}437$ pg/mL(group I), $1,006{\pm}532$ pg/mL(group II), and $764{\pm}302$ pg/mL(group III), retrospectively. In histologic score, the score of group III($1.6{\pm}0.6$) was significantly lower than that of group I($2.8{\pm}1.2$)(p<0.05). Conclusion: In pressure-controlled hemorrhagic shock model, it is suggested that hypothermia might inhibit the direct damage of ischemic tissue through reduction of basic metabolic rate in shock state compared to normothermia. It seems that hypothermia should be benefit to recovery pulmonary function by reducing replaced fluid volume, inhibiting anti-inflammatory agent(IL-8) and leukocyte infiltration in state of ischemia-reperfusion injury. However, if is considered that other changes in pulmonary damage and inflammatory responses might induce by not only kinds of fluid solutions but also hypothermia, and that the detailed evaluation should be study.