• Journal of Soil and Groundwater Environment
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• v.23 no.6
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• pp.104-113
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• 2018

A three-dimensional electrochemical process using nanosized zero-valent iron (NZVI)/activated carbon (AC) particle electrode and persulfate (PS) was developed for oxidizing pollutants. X-ray diffraction (XRD), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), and Brunauer-Emmett-Teller (BET) surface area analysis were performed to characterize particle electrode. XRD and SEM-EDS analysis confirmed that NZVI was impregnated on the surface of AC. Compared with the conventional two-dimensional electrochemical process, the three-dimensional particle electrode process achieved three times higher efficiency in phenol removal. The system with current density of $5mA/cm^2$ exhibited the highest phenol removal efficiency among the systems employing 1, 5, and $10mA/cm^2$. The removal efficiency of phenol increased as the Fe contents in the particle electrode increased. The particle electrode achieved more than 70% of phenol removal until it was reused for three times. The sulfate radical played a predominant role in phenol removal according to the radical scavenging test.

• Journal of the korean Society of Automotive Engineers
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• v.15 no.2
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• pp.92-104
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• 1993

In the present study, the velocity profiles and entrance length of developing transitional pulsating flows are investigated both analytically and experimentally in the entrance region of a square duct. The systems of conservation equations for transitional pulsating flows in a square duct are solved analytically by linearizing the non-linear convective terms. Analytical solutions are obtained in the form of infinite series for velocity pofiles. The experimental study for the air flow in a square duct(40mm*40mm*4000mm) is carried out to measure velocity profiles and other parameters by using a hot-wire anemometer with a data acquisition and processing system. The distribution of velocity profiles( $u_{ps}$ / $u_{m,ta}$) in the decelerating period is higher than in the accelerating period. The distribution of the axial component of the axial component of velocity in the transitional flow is nearly uniform in the central region of the duct, and decrease rapidly near the wall. The entrance length correlation of the transitional pulsating flows in a square duct is obtained to be $L_{e}$/ $D_{h}$=0.83 $A_{1}$R $e_{ta}$ /(.omega. sup+1)$^{2}$TEX>

• The Journal of Korean Medicine
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• v.37 no.2
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• pp.104-109
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• 2016

Objectives: A 74-year-old male patient with unresectable advanced gastric cancer (clinical initial stage T3N+, Borrmann type III) admitted due to gastric bleeding at tumor site. On first admission day, hemoglobin level was 5.7g/dl and performance status was grade 3 according to Eastern Cooperative Oncology Group Performance Status(ECOG-PS). After performing red blood cell transfusion as an emergency treatment, hemoglobin level was increased up to 9.5g/dl. However, bleeding of oozing site was continued. For hemostasis, decoction of notoginseng radix (30g/day) was administered since day 7 after admission. The dose was elevated to 40g/day after hemoglobin level was decreased to 6.5g/dl on day 11. Since then, melena was stopped and hemoglobin level was maintained over 9.1g/dl. This case shows the hemostasis effect of decoction of notoginseng radix on gastric bleeding in unresectable advanced gastric cancer.

• Journal of Food Hygiene and Safety
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• v.38 no.2
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• pp.37-45
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• 2023

The surge in food delivery systems during the coronavirus 2019 pandemic necessitated this study of heavy metal migration from food contact materials (FCMs). A total of 104 samples of FCMs, comprising 51 polypropylene (PP), 21 polyethylene (PE), and 32 polystyrene (PS) samples of six different types of FCMs (containers, covers, table utensils, cups, pouches, and wrappers) used for food delivery distributed in Korea, were collected and investigated for migration of three heavy metals (Pb, Cd, and As) using inductively coupled plasma-mass spectrometry (ICP-MS) to determine whether they complied with Korea's Standards and Specifications for Utensils, Containers, and Packages. Acetic acid (4%, v/v) was used as the food simulant, and tests were performed at 100℃ (in harsh conditions) for 30 min. Linearity of Pb, Cd, and As showed acceptable results with a coefficient of determination (R²) value of 0.9999. Limit of detection (LOD) and limit of quantification (LOQ) of Pb, Cd, and As were 0.001, 0.001, and 0.001 ㎍/L and 0.002, 0.003, and 0.003 ㎍/L, respectively. Accuracy and precision results complied with the criteria presented in the European Commission Joint Research Centre guidelines. The average concentration of Pb, Cd, and As migration detected in a total of 104 samples was 0.009-0.260 ㎍/L, which was very low compared with the migration specification set in the Standards and Specifications for Utensils, Containers, and Packages. The maximum level of Pb corresponded to 0.23% of the migration limit. There were no samples exceeding the limit. Thus, this study confirmed that the heavy metal contents of FCMs used for delivery food distributed in Korea were safely managed. The data from this study represent an invaluable source for science-based safety management of hazardous heavy metals migrating from FCMs used in the food delivery industry.

• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.58-65
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• 2003

Various physicochemical parameters for the active ingredients of 245 herbicides were calculated to develope a diagnosis and estimation system for utility as herbicide. The range of physico-chemical parameters for each inhibitors of photo system II (H1), acetolactate synthase (ALS) (H2) and herbicides were confirmed. The distribution ranges of 85% dependence for each physicochemical parameters were Obs.logP :$-0.90\sim4.50$, dipol moment: $1.80\sim12.22$ (debye), molecular refractivity: $53.0\sim104.0(cm^3/mol)$, polarizability: $19.0\sim37.0(\AA^3)$, HOMO energy: $-9.98\sim-7.34$ (eV), LUMO energy:$-2.76\sim0.40$ (eV), Van der Waals molecular volumes: $558.0\sim995.0(cm^3)$, molecular weight: $202.0\sim430.0$ (amu) and surface areas (Grids): $194.0\sim356.0(\AA^2)$, hydration energy: $-10.16\sim114.7$ Kcal/mol, respectively. It is suggested that MR and polarizability constants will be able to distinguish between herbicides and medicinal drugs. Results revealed that various compounds based on the range of physicochemical parameters of herbicides could be diagnosed and estimated.

• Journal of Chest Surgery
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• v.24 no.9
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• pp.853-860
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• 1991

A clinical study on 139 cases of operated PDA was performed during period from Aug. 1982 to Apr. 1991 at the Dept. of Thoracic and Cardiovascular Surgery of Chonbuk National University Hospital. The following results are obtained. 1. The 35 males and 104 females ranged in age from 6 months to 40 years. [mean 10.2 yrs. ] 2. Chief complaints of the patients were frequent URI in 50%, dyspnea on exertion in 31.2%, palpitation in 11.1%, and no subjective symptoms in 28.78% 3. On auscultation, continuous machinery murmur heard in 79.86% and systolic murmur in 20.14%. 4. Radiologic findings of chest P-A showed increased density of pulmonary vascularity in 80.58%, cardiomegaly in 61.87%, and within normal limit in 19.42% of the patients. 5. The signs of LVH[44.4%], RVH[17.4%], BVH[7.6%] were noted on the EKC. 6. Cardiac catheterizations were performed in 114 patients. The mean Qp/Qs was 2.65 and the mean Pp /Ps was 0.41 and the mean systolic pulmonary artery pressure was 46.6 mmHg. 7. Operative methods were as followed: The 130 cases[93.52%] of ligation and 3 cases[2.16%] of division & suture for PDA were performed through the left posterolateral thoracotomy. And the remained cases were managed under the cardiopulmonary bypass. 8. Operative complications were hoarseness in 8 cases, atelectasis in 6 cases, intraoperative ductal rupture under the left thoracotomy approach 2 cases, recannalization 1 case and others in 3 cases. 9. One patient died due to ductal rupture intraoperatively and the overall mortality was 0.7%.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.4
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• pp.322-334
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• 2007

This study covers the investigation of the actual condition in the workplace to produce plastics products using synthetic resins and the investigation on the trends amount of the domestic production of thermoplastic resins. To analyze the monomers included in thermoplastic resins frequently used in the workplace, we analyzed thermal characteristics for test compounds using thermogravimetric analysis and did the qualitative analysis using Pyrolyzer GC-MSD & TDS GC-MSD. And then we classified the health hazard of monomers based on GHS classification criteria using information toxicity & carcinogenicity. The number of the workplace to produce plastics products among all domestic manufacturers of 73,884 was 4,391 (5.94%). The number of workers to produce plastics products among all workers of 2,522,750 in all domestic manufacturers was 104,971 (4.16%). The amount of production per year for thermoplastic resins is in the order of PP, HDPE, LDPE, PVC, ABS, PS and such compounds was producing over 1 Million ton per year each. The classification result based on GHS classification criteria for 22 main compounds included thermoplastic resins says 2 compounds of acrylonitrile, naphthalene are in Acute oral category 3 and benzene is in Acute dermal category 1. The classification results of health hazard of carcinogenicity based on IARC & ACGIH carcinogen classification says 2 compounds of benzene, vinyl chloride are in category 1A (known to be human carcinogens).

• Journal of Nutrition and Health
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• v.32 no.1
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• pp.83-89
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• 1999

The present study was conducted to investigate the yields of volume, thiamin and riboflavin from the milk of twenty-five Cesarean-section women, and their ingestion in infants. We measured the consumed volume of human milk of infants by the test-weighing method, and thiamin riboflavin contents were determined by fluorescence spectroscopy during the first 7 days postpartum. Thiamin contents of the milk averaged 24.3, 24.0, 27.4 and 30.2ug/100g. Thiamin and riboflavin contents of the milk both increased during the lactation ps mod(p<0.05). The first secretion of breast milk occurred from the 4th to 5th day postpartum in Cesarean-section women. The consumed volume of human milk was 63, 81, 104 and 133g/day at 4, 5, 6 and 7 days postpartum and the consumed volume of formula milk was 58, 176, 292, 323, 308, 321 and 318g/day at 1, 2, 3, 4, 5, 6 and 7 days postpartum and the consumed volume of formula from the human and formula milk were 26.6, 91.0, 151.0, 172.5, 169.2, 175.9 and 172.9ug/day. Total daily riboflavin ingestion from the human and formula milk were 26.6, 91.0, 151.0, 172.5, 169.2, 175.9 and 172.9ug/day. Total daily riboflavin ingestion from the human and formula milk was 48.7, 166.8, 277.6, 318.2, 312.0, 327.0 and 335.7ug/day at 1, 2, 3, 4, 5, 6 and 7 postpartum. These results suggest that the milk secretion of Cesarean-section women is delayed a few days and the yield volume of milk is less than that of normal delivery women, but thiamin and riboflavin contents of the milk are not different from those of milk of normal-delivery women.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.347-354
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• 2007

This paper describes on the real-time monitoring of net setting and hauling process for fishing operations of Danish seine vessels in the southern waters of Korea as an application of a PC based ECDIS system. Tracking of fishing process was performed for the large scale Danish seine vessel of G/T 90 and 350 PS class using the fishing gear which the length of net, ground rope, head rope and sweep line including warp in both sides were 86m, 104m, 118m and 3,200m, respectively. Tracking information for net setting and hauling process was continuously recorded for 23 fishing operations performed on November and December, 2003. All measurement data, such as trawl position, heading, towing course and past track which was individually time stamped during data acquisition, was processed in real time on the ECDIS and displayed simultaneously on the ENC chart. The results indicated that after the separation of a marker buoy from Danish seiner, the averaged running speed of vessel and the averaged setting period while shooting the seine on the course of diamond shape to surround the fish school in the 23 fishing operations were 8.3 knots and 13.1 minutes, respectively. And with the maker buoy taken on board, the averaged running speed of vessel and the averaged towing period while closing the seine on the straight route was 1.0 knots and 47.0 minutes, respectively. After the closing stage of hand rope, the hand rope was towed by the averaged speed of 2.2 knots during the 13.0 minutes. The average area for route of diamond shape swept by sweep lines of the seine in 23 fishing grounds was $709,951.6m^2$. Further investigation is also planed to provide more quantitative tracking information and to achieve more effective surveillance and control of Danish seine vessels in EEZ fishing grounds.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.1
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• pp.95-104
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• 2002

A methods to calculate non-linear moment-curvature relations of high-strength PSC flexural members for numerical analysis has been proposed. The moment-curvature relations were calculated with assumptions of design codes and by the layer method. The results of the proposed procedures for moment-curvature relations and numerical analysis were compared with those of pre-existing tests. The absorption energy rate of the design codes was about 30% larger than that of the layer method. The ultimate load and the external work of the layer method were 90% and 85% of those of tests, respectively The ultimate load of the strength design method was 97% of that of tests, but the external work was over-estimated with 122%. The ultimate load and external work by the proposed equation of the CEB-FIP Model Code were 113% and 173% of those of tests, respectively. It show that the use of ultimate strain of 0.0035 should be over-estimated for high-strength concrete. The procedure of non-linear numerical analysis of this research could be stably simulated the behavior of concrete flexural members until the ultimate state, and calculate results of the load-deflection relation and cracking pattern were very similar with those of tests.