• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.1-26
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• 1994

The purpose of this study was to investigate the dissolution components during corrosion of amalgams and to identify surface corrosion products in the modified Fusayama artificial saliva. Four type of amalgam alloys were used: low copper lathe cut amalgam alloy (Cavex 68), low copper spherical amalgam alloy (Caulk Spherical Alloy), high copper admixed amalgam alloy (Dispersalloy) and high copper single composition amalgam alloy (Tytin). Each amalgam alloy and Hg were triturated according to the manufacturer's direction by means of mechanical amalgamator (Capmaster, S.S.White), and then the triturated mass was inserted into the cylindrical metal mold which was 10mm in diameter and 2.0mm in height and condensed with compression of 150kg/$cm^2$ using oil pressor. The specimens were removed from the mold and stored at room temperature for 7 days and cleansed with distiled water for 30 minutes in an ultrasonic cleaner. The specimens were immersed in the modified Fusayama artificial saliva for the periods of 1 month, 3 months and 6 months. The amounts of Hg, Cu, Sn and Zn dissolved from each amalgam specimen immersed in the artificial saliva for the periods of 1 month, 3 months and 6 months were measured using Inductivity Coupled Plasma Atomic Emission Spectrometry (ICPQ-1000, Shimadzu, Japan) and amount of Ag dissolved from amalgam specimen was measured using Atomic Absorption Spectrophotometry (Atomic Absorption/Flame emission spectrophotometer M-670, Shimadzu, Japan). A surface corrosion products of specimens were analysed using Electron Spectroscopy Chemical Analyser (ESCA PHI-558, PERKIN ELMER, U.S.A.). The secondary image and back scattered image of corroded surface of specimens was observed under the SEM, and the corroded surface of specimens was analysed with the EDX. The following results were obtained. 1. The dissolution amount of Cu was the most in high copper admixed amalgam(Dispersalloy) and the least in high copper single composition amalgam(Tytin). 2. Sn and Zn were dissolved during all the experiment periods, and dissolution amounts were decreased as the time elapsed. 3. Initial surface corrosion products were ZnO and SnO. 4. Corrosion of ${\gamma}$ and ${\gamma}_2$ phase in low copper amalgams was observed and Ag-Cu eutectic alloy phase was corroded in low copper spherical amalgam(Caulk Sperical Alloy). 5. Corrosion of ${\gamma}$ and $\eta$' phase in high copper amalgams was observed and Ag-Cu eutectic alloy phase was corroded in high copper admixed amalgam(Dispersalloy). 6. Sn-Cl was produced in the subsurface of low copper amalgams and high copper admixed amalgam.

• Journal of environmental and Sanitary engineering
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• v.23 no.2
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• pp.71-79
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• 2008

We examined 165 unchlorinated natural drinking water samples for the presence of E. coli group resistant to antimicrobial agent and chlorine in nothern Gyeongbuk area in 2007. Among 165 water samples, 21 samples(12.7%) were positive to total coliforms and Six genus, 16 strains of E. coli groups isolated from 16 samples showed resistance against more than one antimicrobial agent such as Ampicillin, Tetracycline and Chloroamphenicol. Among 16 strains, 14 strains resistant to Ampicillin, 9 strains resistant to Tetracycline and one strain resistant to Chloroampenicol. but all 16 strains did not contain any integron gene cassettes, which contribute to the spread of antimicrobial resistance alleles by lateral gene transfer of gene cassettes in a variety of enteric bacteria. The minimal inhibitory concentration(MIC) of 14 strains which showed resistant to Ampicillin was between $12{\mu}g/m{\ell}$ and $32{\mu}g/m{\ell}$, Nine strains resistant to Tetracycline showed between $32{\mu}g/m{\ell}$ and $128{\mu}g/m{\ell}$ and one strain resistant to Chloroampenicol showed $128{\mu}g/m{\ell}$. The chlorine sensitivity of 16 strains isolated from unchlorinated natural water sample did not show any difference among strains by the concentration of initial free chlorine and elapsed time after chlorine treatment. All 16 strains were killed after 1hr. exposure at $0.2mg/m{\ell}$ of free chlorine per liter or 30minutes exposure at $0.4mg/m{\ell}$ of free chlorine per liter.

• Korean Journal of Applied Biomechanics
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• v.18 no.3
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• pp.33-42
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• 2008

The purpose of this study was to analyze kinematic variables during Side kick motion in Taekwon Aerobics. The subjects of this study were the 7 skilled and 7 unskilled female college students. A QTM and an Auto Track were used to acquire raw data. The sampling rates camera was 100 Hz. The parameters were calculated and analyzed with Visual3D and SPSS 12.0. The results were as following; 1. In the elapsed time, there was no significance difference statically between a skilled and unskilled group. 2. In the cases of knee angle, there was significant difference statically at Maximum Knee Flexion2(p=0.046, F=4.925). 3. In the cases of knee angular velocity, there was significant difference statically at Maximum Knee Flexion1(p=0.031, F=5.940). 4. In the flexion/extension of hip angle, there was significant difference statically at Maximum Knee Flexion2(p=0.012, F=8.668). 5. In the abduction/adduction of hip angular velocity, there was significant difference statically at Minimum Knee Flexion (p=0.019, F=7.324). 6. In the external rotation/internal rotation of hip angular velocity, there was significant difference statically Minimum Knee Flexion(p=0.005, F=11.87).

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.238-243
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• 2007

This report describes the retained surgical gauze in two dogs that had ovariohysterectomy previously. The elapsed time between surgery and diagnosis of retained surgical gauze in two dogs was 30 and 16 months, respectively. Radiographic signs included localized abdominal mass (case 1, 2) and soft tissue swelling (case 2). Retained surgical gauze was imaged by survey radiography, ultrasonography and computed tomography (CT). Ultrasonography revealed a hypoechoic mass with irregular hyperechoic center in case 1, and hypoechoic mass with oval hyperechoic center and acoustic shadowing in case 2. In CT examination of case 2, hyperdense mass with a thick peripheral rim enhancing in contrast study was shown. Cytologic examination of both cases revealed abscess and granuloma respectively. The lesions were surgically removed. The possibility of retained surgical gauze should be considered in animals with a history of previous surgery with abnormal mass.

• Anxiety and mood
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• v.4 no.1
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• pp.34-41
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• 2008

Objective : The aim of this study is to examine the characteristics of somatic symptoms in patients with PTSD according to trauma type. Methods : The subjects of this study were 84 patients diagnosed with PTSD according to the DSM-IVTR and CAPS criteria. The subjects ranged in age from 18 to 76 years, and they were recruited from 18 hospitals across the nation. All participants were asked about their trauma history, and they all completed the Davidson Trauma Scale (DTS), Beck Depression Inventory (BDI), State-Trait Anxiety Inventory (STAI), Impact of Event Scale-Revised (IES-R) and Korean-Physical Somatic Symptom Inventory (K-PSI). The items of the K-PSI were categorized into 5 groups according to organ system, and the participants were classified into 6 groups according to trauma type. We compared the results of the social demographical scale, DTS, BDI, STAI, IES-R and each recategorized subscale of the K-PSI among the six groups. Results : There were significant differences between the 6 groups in terms of the Korean-Physical Somatic Symptom Inventory scores for each organ system, except for the cardiopulmonary system, as well as the BDI scores. Post hoc analysis revealed differences between the combat-related trauma group and all other groups but not among any of the other groups. Conclusion : Our result showed that there were significant differences in the somatic symptom scores among the 6 trauma groups. However, patient age and the time elapsed since the traumatic event may have hada crucial influence on the result of this study.

• Food Science and Preservation
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• v.14 no.2
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• pp.131-135
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• 2007

We investigated the effects of pediocin on physicochemical and microbial changes in soybean cut 9 days of storage at $10^{\circ}C$, in order to improve shelf-life. As the storage time of curd increased the pH of solutions treated by pediocin immersion did not vary greatly, whereas the pH of control curd decreased after 5 days of storage. Titratable acidity increased in non-treated curd after 5 days of storage, and also in cud immersed in pediocin solutions of 300 and 500 ppm, after 6 and 7 days of storage, respectively. A pediocin solution of 1,000 ppm the development of titratable acidity. Also, turbidity did not increase during storage of curd treated with a pediocin solution of 1,000 ppm. The bacterial count of the immersion solution was $10^{2.5}$ CFU/mL at the commencement of storage, remained stable for 5 days of storage, and then increased rapidly. Coliforms were detected in untreated curd after 2.5days of storage. In curd treated with 300, 500 or 1,000ppm of pediocin, the elapsed times to coliform detection were 3.5 days, 5 days and 7 days, respectively, It is thus possible to prevent the deterioration of soybean curd with pediocin treatment.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.1
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• pp.3-10
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• 1988

A laboratory study was carried out to investigate the effects of application level of soil amendments, mixing method of soil amendments, and compost treatment on desalinization by examining the changes in hydraulic conductivity and chemical properties of effluent of the soil during desalinization. 1. The treatment of soil amendments brought about the increase in hydraulic conductivity. 2. The higher the application level of a soil amendment, the higher the hydraulic conductivity and the shorter the time elapsed to complete the desalinization. 3. Complete mixing of calcium compounds was more effective for desalinization than surface mixing. 4. The compost treatment induced the rise in pH and therefore brought about the remarkable drop in hydraulic conductivity. 5. During the desalinization, the changes in physical and chemical properties of the soil were influenced by the kind and application level of soil amendments, mixing method of soil amendment, and compost treatment.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.364-368
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• 2007

The objective of this study was to characterize organic mater decomposition with application of livestock manure compost in upland soil. Six different composts, which were chicken (CHM), pig (PIM), and cow (COM) manure compost added and chicken (CHMS), pig (PIMS), cow (COMS) manure compost with sawdust added, were prepared for this study. These composts have different composition of crude carbohydrate (hemicellulose, cellulose, and lignin). The buried-bag method was used to determine the rate of organic mater decomposition and the changes of crude carbohydrate content during 36 months in the field. In all treatment, hemicellulose content was sharply decreased within 8 months, but considerable amount of lignin was remained after 36 months. After 40 months, the rates of carbon decreasing were 81, 80, 72, 69, 67, and 64 % for CHM, PIM, COM, CHMS, PIMS, and COMS, respectively. The estimated equation of carbon decreasing rate (D), $D=aT^b$, was fit to the carbon decreasing rate vs. elapsed time (T) using a non-linear regression procedure. After 40 months, significant difference of carbon decreasing rate between observed and estimated was not found. The relationship between constant a, b and hemicellulose content in the compost was not observed in this experiment. The cellulose and lignin content in the compost were positively correlated to the constant b and negatively correlated to the constant a.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.2
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• pp.95-111
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• 2021

As the population decreases in an aging society, the average age of drivers increases. Accordingly, the elderly at high risk of being in an accident need autonomous-driving vehicles. In order to secure driving safety on the road, several technologies to respond to various obstacles are required in those vehicles. Among them, technology is required to recognize static obstacles, such as poor road conditions, as well as dynamic obstacles, such as vehicles, bicycles, and people, that may be encountered while driving. In this study, we propose a deep neural network algorithm capable of simultaneously detecting these two types of obstacle. For this algorithm, we used 1,418 road images and produced annotation data that marks seven categories of dynamic obstacles and labels images to indicate road damage. As a result of training, dynamic obstacles were detected with an average accuracy of 46.22%, and road surface damage was detected with a mean intersection over union of 74.71%. In addition, the average elapsed time required to process a single image is 89ms, and this algorithm is suitable for personal mobility vehicles that are slower than ordinary vehicles. In the future, it is expected that driving safety with personal mobility vehicles will be improved by utilizing technology that detects road obstacles.

• Food Science and Industry
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• v.52 no.2
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• pp.130-139
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• 2019

Safety of genetically modified foods (GM foods) in Korea is evaluated according to "Food Sanitation Act" and "Regulation on safety evaluation for GM foods" based on the concept of substantial equivalence. In which cases a person who imports, develops or manufactures GM foods for the purpose of eating imports GM foods for the first time, he/she shall undergo a safety evaluation of the relevant foods, etc. by Ministry of Food and Drug Safety (MFDS). And in which cases ten years have elapsed since GM foods underwent safety evaluation, they shall be re-evaluated for their safety. As of April 2019, a total of 199 events have been approved by MFDS and they are 169 events of GM crops including soybean (29), maize (87), cotton (29), canola (14), sugar beet (1), potato (4), alfalfa (5), 6 events of GM microorganisms (GMM) and 24 events of GM food additives originated from GMM.