• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.659-668
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• 2006

The optimization of supercritical water oxidation (SCWO) process for decomposing nitromethane was studied by means of a design of experiments. The optimum operating region for the SCWO process to minimize COD and T-N of treated water was obtained in a lab scale unit. The authors had compared the results from a SCWO pilot plant with those from a lab scale system to explore the problems of scale-up of SCWO process. The COD and T-N in treated waters were selected as key process output variables (KPOV) for optimization, and the reaction temperature (Temp) and the mole ratio of nitromethane to ammonium hydroxide (NAR) were selected as key process input variables (KPIV) through the preliminary tests. The central composite design as a statistical design of experiments was applied to the optimization, and the experimental results were analyzed by means of the response surface method. From the main effects analysis, it was declared that COD of treated water steeply decreased with increasing Temp but slightly decreased with an increase in NAR, and T-N decreased with increasing both Temp and NAR. At lower Temp as $420{\sim}430^{\circ}C$, the T-N steeply decreased with an increase in NAR, however its variation was negligible at higher Temp above $450^{\circ}C$. The regression equations for COD and T-N were obtained as quadratic models with coded Temp and NAR, and they were confirmed with coefficient of determination ($r^2$) and normality of standardized residuals. The optimum operating region was defined as Temp $450-460^{\circ}C$ and NAR 1.03-1.08 by the intersection area of COD < 2 mg/L and T-N < 40 mg/L with regression equations and considering corrosion prevention. To confirm the optimization results and investigate the scale-up problems of SCWO process, the nitromethane was decomposed in a pilot plant. The experimental results from a SCWO pilot plant were compared with regression equations of COD and T-N, respectively. The results of COD and T-N from a pilot plant could be predicted well with regression equations which were derived in a lab scale SCWO system, although the errors of pilot plant data were larger than lab ones. The predictabilities were confirmed by the parity plots and the normality analyses of standardized residuals.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1475-1485
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• 2012

This study was conducted in order to understand nutrition teachers (dietitians)' perceptions of barriers to implementation of HACCP system in school foodservices in Gyeongnam, Korea. Questionnaires were distributed to 350 nutrition teachers (dietitians) from November to December of 2009, and 214 were collected and analyzed. The results of this study were as follows. First, nutrition teachers (dietitians) recognized the following as barriers in implementing the HACCP system: 'the status of facilities and utilities'> 'monitoring'> 'work satisfaction'> 'foodservice employees'> 'cooperation of HACCP team'> 'cooperation of persons concerned besides foodservice employees'> 'understanding the HACCP system'. Second, total working experience was found to be the factor most affecting 'cooperation of HACCP team (p<0.01)', 'cooperation of persons concerned besides foodservice employees (p<0.01)', 'foodservice employees (p<0.05)', and 'work satisfaction (p<0.05)'. Further, 'the status of facilities and utilities' was significantly affected by 'construction/reconstruction of kitchen (p<0.01)', 'division of kitchen area (p<0.01)', 'existence of preliminary preparation room (p<0.01)', and 'existence of dishwashing room (p<0.01)'. Third, dietitians perceived the following concerning hindrance factors of the HACCP system according to CCP stage: 'CCP 1'> 'CCP 3'> 'CCP 2, 'CCP 6'> 'CCP 4'> 'CCP 8'> 'CCP 7'> 'CCP 5'. In conclusion, this study showed that nutrition teachers (dietitians) in the Gyeongnam area recognized 'the status of facilities and utilities' from HACCP areas and 'CCP 1 (menu planning)' from CCP stages as the greatest barriers to implementing the HACCP system in school foodservices. To implement the HACCP system successfully in school foodservices, facilities and utilities should be properly equipped, and menu planning training for nutrition teachers (dietitian) should be conducted.

• The Journal of Engineering Geology
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• v.14 no.1
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• pp.29-46
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• 2004

It is important to identify geometries of fracture that act as a conduit of fluid flow for characterization of ground water flow in fractured rock. Fracture geometries control hydraulic conductivity and stream lines in a rock mass. However, we have difficulties to acquire whole geometric data of fractures in a field scale because of discontinuous distribution of outcrops and impossibility of continuous collecting of subsurface data. Therefore, it is needed to develop a method to describe whole feature of a target fracture geometry. This study suggests a new approach to develop a method to characterize on the whole feature of a target fracture geometry based on the Fourier transform. After sampling of specimens along a target fracture from borehole cores, effective frequencies among roughness components were selected by the Fourier transform on each specimen. Then, the selected effective frequencies were averaged on each frequency. Because the averaged spectrum includes all the frequency profiles of each specimen, it shows the representative components of the fracture roughness of the target fracture. The inverse Fourier transform is conducted to reconstruct an averaged whole roughness feature after low pass filtering. The reconstructed roughness feature also shows the representative roughness of the target subsurface fracture including the geometrical characteristics of each specimen. It also means that overall roughness feature by scaling up of a fracture. In order to identify the characteristics of permeability coefficients along the target fracture, fracture models were constructed based on the reconstructed roughness feature. The computation of permeability coefficient was performed by the homogenization analysis that can calculate accurate permeability coefficients with full consideration of fracture geometry. The results show a range between $10^{-4}{\;}and{\;}10^{-3}{\;}cm/sec$, indicating reasonable values of permeability coefficient along a large fracture. This approach will be effectively applied to the analysis of permeability characteristics along a large fracture as well as identification of the whole feature of a fracture in a field scale.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.77-92
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• 2014

Fermented foods have often been implicated as causative agents in poisoning due to toxic levels of biogenic amines. Cheese, a milk-based fermented food, is the product most likely to contain potentially harmful levels of biogenic amines, such as tyramine, histamine, putrescine, and so on. Recently, the risk awareness of a dietary uptake of high loads of biogenic amines has increased. Hence, we here review the published literature on several factors known to affect the biosynthesis of biogenic amines and their accumulation in milk-based foods. Furthermore, with regard to risk analysis, we discuss the control of factors related to the synthesis and accumulation of biogenic amines as a means to reduce their incidence in milk-based products, and thus to increase food safety.

• Journal of Nutrition and Health
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• v.50 no.5
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• pp.460-471
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• 2017

Purpose: The purpose of this cross-sectional study was to investigate intake-related factors of energy drinks and educational needs regarding energy drinks in female high school students. Methods: Subjects were 340 female high school students in Incheon, and data were collected using self-administered questionnaires. Statistical analysis was performed using the SPSS 20.0 program. Results: Subjects who had drunk energy drinks were 74.3% (249 subjects) of all subjects. The first time they drank an energy drink was significantly associated with grade (p < 0.05). In 75.1% of 249 subjects who had drunk energy drinks, the places for buying energy drinks were supermarkets and convenience stores near their homes. For the effects of energy drink intake, sleeplessness (44.6%) and no effect (41.7%) were cited, and 24.5% experienced side effects such as palpitation, tremors, etc. The scores for self-diagnosis of caffeine addiction were significantly higher in the low weight group compared to the overweight group (p < 0.05). The degree of caffeine addiction was significantly associated with effects of energy drink intake (p < 0.001) and type of side effects (p < 0.001). Willingness to stop consuming energy drinks (p < 0.001) and necessity of nutrition education about energy drinks (p < 0.05) were significantly lower in the caffeine addiction group compared to the general group. About 75.0% of subjects wanted to be educated about the side effects of energy drinks and caffeine. Conclusion: This study shows that female high school students need proper education about the effects of intake of energy drinks. Therefore, guidelines and a nutrition education program right intake of energy drinks should be provided as well as campaigns concerning the side effects of energy drinks and caffeine in female high school students.

• Journal of Chest Surgery
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• v.34 no.12
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• pp.901-908
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• 2001

Background : Coronary artery bypass graft(CABG) in patients with advanced left ventricular dysfunction has often been regarded as having high mortality rate, despite the great improvement in operative result of CABG. With recent advances in surgical technique and myocardial protection, surgical revascularization improved the symptom and long-term survival of these high risk patients more than the medical conservative treatment. Material and Methold : Clinical data of 31(4.1％) patients with preoperative ejection fraction less than 30% among 864 CABGs performed between January 1995 and March 1999 were retrospectively analyzed and pre- and postoperative changes of the ejection fraction on echocardiography were analyzed. There were 26 men and 5 women. The mean age was 60.7 years(range 41 to 72 years). History of myocardial infarction(30 cases, 98％) was the most common preoperative risk factor. There were seven irreversible myocardial infarction on thallium scan. Most patients had triple vessel diseases(26 cases, 84％) and first degree of Rentrop classification(16 cases, 52％) on coronary angiography. The mean number of distal anastomosis during CABG was per patient was 4.9${\pm}$0.8 sites in each patient. In addition to long saphenous veins, the internal mammary artery was used in 20 patients. Total bypass time was 244.7${\pm}$3.7 minutes(range, 117 to 567 minutes), and mean aortic cross-clamp time was 77.9 ${\pm}$ 1.6 minutes(range, 30 to 178 minutes). There were five other reparative procedures such as two left ventricular aneurysrmectomy, two mitral repair, and one aortic valve replacement. There were twelve postoperative complications such as three cardiac arrhythmia, two bleeding(re-operation), one delayed sternal closure, eleven usage of intra-aortic balloon counterpulsation for low cardiac output. Two patients died, postoperative mortality was 6.5% . Twenty-nine patients were relieved of chest pain and left ventricular ejection fraction after operation was significantly higher(38.5${\pm}$11.6%, p 0.001) as compared with preoperative left ventricular ejection fraction(25.3${\pm}$2.3%). The follow up period of out patient was 25. 3 months. Conclusion: In patients with coronary artery disease and advanced left ventricular dysfunction, coronary artery bypass grafting can be performed relatively safely with improvement in left ventricular function, but it will be necessary to study long term results.

• Journal of Chest Surgery
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• v.40 no.6 s.275
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• pp.414-419
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• 2007

Background: Replacing the ascending aorta is a standard surgical option for treating acute type A aortic dissection. But replacing the aortic arch has recently been reported as an acceptable procedure for this disease. We compared the effects of aortic arch replacement for treating acute type A aortic dissection with the effects of ascending aortic replacement. Material and Method: From 2002 to 2006, 25 patients undewent surgical treatment for acute type A aortic dissection, 12 patients undewent ascending aortic replacement and 13 patients underwent aortic arch replacement. Among the aortic arch group, an additional distal stent-graft was inserted during the operation in 5 patients. 19 patients (11 arch replaced patients and 8 ascending aortic replaced patients) were followed up at the out patient clinic for an average of $756{\pm}373$ days. All the patients undewent CT scanning and we analyzed their distal aortic segments. Result: 4 patients who underwent ascending aortic replacement died, so the overall mortality rate was 16%. Among the 11 long term followed-up arch replacement patients, 2 patients (18.1 %) developed distal aortic dilatation and one of them underwent thoracoabdominal aortic replacement later on. However, among the 8 the ascending aortic replaced patients, 5 patients (62.5%) developed distal aortic dilatation. Conclusion: Aortic arch replacement is one of the safe options for treating acute type A aortic dissection. Aortic arch replacement for treating acute type A aortic dissection could contribute to a reduced distal aortic dilatation rate and fewer secondary aortic procedures.

• Journal of Chest Surgery
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• v.40 no.6 s.275
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• pp.420-427
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• 2007

Background: Postpneumonectomy empyema (PPE) due to bronchopleural fistula (BPF) can be a surgical challenge for surgeons. We analyzed the follow-up outcomes after performing omentopexy and thoracoplasty for the treatment of PPE with BPF after pneumonectomy. Material and Mehod: Between December 1991 and January 2006, 9 patients underwent BPF closure using an omental pedicled flap for the treatment of PPE with BPF after pneumonectomy. There were 7 males and 2 females (mean age: $45.9{\pm}9$ years). The patients were followed up for a mean of 58 months (median: 28 months, range: $6{\sim}169$). When we performed omentopexy, the surgical procedures for empyema were thoracoplasy for 8 patients and the Clagett procedure for 1 patient. Thoracoplasty was performed for the latter patient due to recurrence of empyema, Result: For the 8 patients who were treated by omentopexy and thoracoplasty, there was 1 operation-related death due to sepsis. During follow up, 1 patient, who was treated by omentopexy and a Clagett procedure, died of acute hepatitis 40 months postoperatively. The early mortality was 11.1% (8/9). Of the 8 patients, including the 1 late death patient, successful closure of the BPF were achieved in all patients (8/9) and the empyema was cured in 7 patients (7/8). Conclusion: The BPF closure using an omental pedicled flap was an effective method for treating PPE with BPF due to 75-destroyed lung, and thoracoplasty with simultaneous omentopexy was effective and safe for removing dead space if the patient was young and in a good general condition.

• The Korean Society of Law and Medicine
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• v.16 no.2
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• pp.55-84
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• 2015

The tuberculosis is the infectious disease. Generally, the active tuberculosis patient can infect the 10 persons for one year within the daily activities like casual conversation and singing together. The infectivity of tuberculosis can continue for a life time, and infected persons can remain at risk for developing active tuberculosis. To control this contagious disease, along with the active tuberculosis patients, non-infectious but non-compliant patients who can be infectious if their immune systems become impaired have to be managed. To control the non-complaint patients, medical treatment order should be combined with the public order. Because tuberculosis is the risk of community health, the human rights like liberty and freedom of movement can be restricted for public welfare under the article 37(2) of constitution. Even when such restriction is imposed, no essential aspect of the freedom or right shall be violated. The degree of restriction on the rights of citizens is different what methods are chosen to non-complaint patients. For example, under the directly observed therapy program, the patients and medical staffs make an appointment and meet to confirm the drug intakes according to the schedule, which is the medical treatment combined with the mildest public order. If the patients break the appointments or have the history of disobedient, the involuntary detention can obtain the legitimate cause. The Tuberculosis Prevention Act has the two step programs on this involuntary detention, The admission order (Article 15) is issued when the patients are infectious. The quarantine order (Artle 15-2) is issued when the patients are infectious and non-complaint. The legal criteria for involuntary detention are discussed and published through the international conventions and covenants. For example, World Health Organization had made guidance on human rights and involuntary detention for tuberculosis control. The restrictions should be carried out in accordance with the our law and in the legitimate objective of public interest. And the restriction should be based on scientific evidence and not imposed in an unreasonable or discriminatory manner. We define and adopt these international criteria under our constitution and legal system. Least restrictive alternative principle, proportionality principle and the individual evaluation methods are explained through the reviews of United States court decisions. Habeas Corpus Act is reviewed and adopted as the procedural due process to protect the patient rights as a citizen. Along with that, what conditions and facilities which are needed to performed quarantine order are discussed.

• Journal of Korean Society of Forest Science
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• v.73 no.1
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• pp.63-69
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• 1986

In general, the snow injury in forestry is an unusual disaster. The degree of snow injury varies greatly depending on stand density and the local topography. This study was conducted to investigate the snow injury in analyzing the demaged by snow-fall in Jinju, Gyeongsangnamdo. The results obtained were summarized as follow; Among 466 total damaged trees, 425 trees were broken and 41 trees were uprooted, the ratio of damage were 5.22%, 2.49%, 0.92% and 0.2% for Pinus densiflora, Pinus thunbergii, Pinus rigida, Alnus hirsuta respectively. The 95% of the damage trees were in the range of 3 to 11 m for height and in the range of 3 to 20 cm for D. B. H.. The directions of the damage trees had a large influence by direction of the wind, but they shown at high tendency to aspect of the slope relatively. The 82% of the damaged trees ranged from 11 to 24 age. The ratio of broken height ($H_B/H$) indicated that the damage was most frequent in the part of stem as 24%, 45%, 31% in the part of the root collar (0.1), stem (0.2-0.4), crown (0.5-1.0) respectively. In general, trees with stem-form coefficient ($H_B/D$) over 0.7-0.8 are apt to suffer by snow damage. The average of stem-form coefficient of trees in this area was 1.06. Therefore, the ratio of damage was high tendency as 3.14%. These results indicate that it is necessary to apply pertinent tending which will increase in resistance of snow damage. As avalanches from the flank of soil erosion rise in an importance matter in present, it should also be considered to measures for prevention and restoration.