• Journal of Korean Society of Environmental Engineers
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• v.37 no.10
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• pp.590-595
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• 2015

Sampling campaigns were conducted for hazardous chemicals and heavy metals in influents and effluents of industrial wastewater treatment plants (WWTPs) in Korea for best management practices (BMPs) of those pollutants through the plants and the receiving water bodies. Twenty seven WWTPs, receiving wastewater from industrial complexes and treating more than $2,000m^3/day$, were selected for the sampling campaign. Influents and effluents of each WWTPs were sampled once a month (total three times per plant) between July and September, 2012, and analyzed for 22 hazardous water pollutants among 28 regulated for effluents limits in Korea. Concentrations of mercury, arsenic, 1,1-dichloroethylene, and benzene in the influents were relatively higher; concentrations of mercury and arsenic in effluents were relatively higher than those of other pollutants. Most of the hazardous chemicals and heavy metals were removed (including phase transfer) more than 60% through the treatment processes except for selenium (30% removal) and 1,4-dioxane (18% removal).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.232-237
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• 1999

The relationship between structure and contractile activity was studied on the three neuropeptide $\gamma$ (mammalian-, bowfin-, shark-NP$\gamma$) that were synthesized by the solid-phase method. Circular dichroism spectra showed that mammalian-, bowfin- and shark-neuropeptide $\gamma$ took an unordered structure in buffer solution and artificial liposome. The intestinal motility response was investigated with guinea-pig ileum, rat duodenum and carp intestine. In case of carp intestine, contractile activity was as follows; bowfin-NP$\gamma$> shark-NP$\gamma$>mammalian-NP$\gamma$, On the other hand, the contractile activity of mammalian-neuropeptide $\gamma$ was more potent than those of bowfin-, shark-neuropeptide $\gamma$ in the guinea-pig ileum and rat duodenum. These results suggest that NP$\gamma$ show the species-specific activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1289-1292
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• 2005

The objective of this study was to characterize and determine contents of vitamin E isomers (alpha-, beta-, gamma-, delta-tocopherols and tocotrienols) in different steamed rice dishes, with or without other grains. Five different rice dishes were evaluated for the vitamin E nutritional value as major Korean staple foods. They were plain steamed rice (SR) and steamed rice mixed with barley (SRBa), red bean (SRRB), black bean (SRBB), or multi-grains (SRMG) containing a mixture of black rice, barley, red beans, and black beans. Vitamin E isomers were extracted from five grams of freeze-dried samples with hexane after saponification. An analytical method, using a normal-phase HPLC with a UV detector, was developed and used to determine the amount of each vitamin E component. The results showed that SR contained three vitamin E isomers (alpha-tocopherol, alpha-tocotrienol, and gamma-tocotrienol). Alpha-tocopherol and gamma-tocotrienol were de-tected from all samples while only SRBB contained beta-tocopherol and beta-tocotrienol. SRMG showed the highest (3.9$\mu$g/g dry wt) and SRRB showed the lowest alpha-tocopherol (1.3$\mu$g/g dry wt) contents. SRBB contained about 5 to 16 times more gamma-tocopherol (19.7$\mu$g/g dry wt) than othe.5. These results suggested that adding black bean or multi-grains can dramatically improve the vitamin E nutritional values compared to the plain steamed rice (SR). Information obtained from this study can be directly related to the amount of vitamin E intake and can be used to balance the diet for Koreans.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.417-426
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• 1997

Rice bran protein hydrolysates were prepared and some of their physicochemical properties were investigated to utilize rice bran as starting material for functional food ingredient. Rice bran proteins (RBP) were prepared from defatted rice bran by alkaline extraction and isoelectric precipitation. The enzyme for hydrolysis of RBP was selected through measuring relative activity by pH-drop method and comparing the degree of hydrolysis (DH) of hydrolysates. The enzymatic hydrolysates prepared by $Esperase^{\circledR}$ treatment were partitioned into two fractions by ultrafiltration(UF) with a 10 kDa molecular weight cut-off membrane. Each fraction was applied to a cholic acid-conjugated ${\omega}-aminohexyl$ Sepharose 4B column and the bile acid-binding components were obtained by eluting with deoxycholate. Gel permeation chromatography on a Sephadex G-50 column revealed that molecular weight of the bile acid-binding fraction of UF permeate was distributed in ranges of $2\;kDa{\sim}10\;kDa$ and $0.2\;kDa{\sim}0.6\;kDa$. Three peaks (R-1, R-2 and R-3) were obtained by prep-HPLC of bile acid-binding fraction of UF retentate and analyzed for total and free amino acid composition. The results showed that proline content of the bile-acid binding polypeptides and peptides was four times as much as that of rice bran protein and that the peak corresponding to higher average hydrophobicity had a higher free amino acid content. Average hydrophobicity slightly increased with enzymatic hydrolysis.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.4 s.316
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• pp.55-60
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• 2007

In high field (> 3 T) MR imaging, the magnetic field inhomogeneity in the target object increases due to the nonuniform electro-magnetic characteristics of the relatively high RF frequency. Especially in the body imaging, the effect causes more serious problems resulting in locally high SAR(Specific Absorption Ratio). In this paper, we propose an optimized parallel-transmission RF coil and show the utility of the coil by FDTD simulations to overcome the unwanted effects. Three types of TX coil elements are tested to maximize the efficiency and their driving patterns(amplitude and phase) optimized to have adequate field homogeneity, proper SAR level, and sufficient field strength. For the proposed coil element of $25cm{\times}8cm$ loop structure with 12 channels for a 3.0 T body coil, the field non-uniformity of more than 70% without optimization was reduced to about 26 % after the optimization of driving patterns. The experimental as well as simulation results show that the proposed parallel driving scheme is clinically useful for (ultra) high field MRI.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.4
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• pp.428-435
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• 2004

With the rapid and wide-spread use of cellular telephones much attention has been focussed on propagation in the urban area crowed with buildings and houses. It is often surrounded by hills, forests, and mountains. The importance of surface scattering intereference between transmitters and receivers on the rough surfaces has been interested and investigated. Therefore, a prediction method is necessary to estimate the influence of rough surfaces on microwave radio propagation. Moreover, most of the mobile communications are performed based on the digital communication system rather than the analog one. In this case, we must pay more careful attention to the signal delay caused by the phase delay due to the multi-path propagation. In this paper we have analyzed numerically scattering of electromagnetic waves from building walls by using FVTD(Finite Volume Time Domain) method. We consider three different types of rough surfaces such as periodic, random, and composite structures. We calculate the bistatic normalized radar cross section (NRCS) for horizontal and vertical polarization, and we take account of the conventional optical reflection which corresponds to the n-th Bragg reflection for periodic structures. In addition, we investigated what conditions are needed in order to be able to ignore the higher order Bragg reflection for the periodic structures.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.1
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• pp.73-89
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• 1991

Impression ragistration is an improtant and difficult phase of prosthodontic treatment procedures and a tray of appropriate size and shape is essential to obtain the accurate impression. Particularly, in edentulous patients, the size and forms of their residual alveolar ridges are different from one another. Therefore, in this study, various measurements were taken on the edentulous models. And the measurements were analyzed and compared with one another. The results were as follows ; 1. The mean of denture bearing area was $32.86cm^2$ in the upper jaws, $24.20cm^2$ in the lower jaws and the variation of denture bearing area was greater in the upper than in the lower jaws and in males than in females. 2. The mean of A-P(anteroposterior) ridge length was 48.72mm in the upper jaws, 53.05mm in the lower jaws and that of males was longer than that of females. 3. The mean of most posterior ridge width was 47.23mm in the upper jaws, 58.03mm in the lower jaws and the difference of that between males and females was least in both jaws. 4. In the upper jaws, the mean of ridge width was 29.66mm on anterior 1/4, 42.79mm on middle, 48.95mm on posterior 1/4 line and the mean of palatal height was 4.56mm on anterior 1/4, 10.01mm on middle, 10.84mm on posterior 1/4 line. 5. In the lower jaws, the mean of ridge width was 33.24mm on anterior 1/4, 50.19mm on middle, 59.16mm on posterior 1/4 line and the mean of lingual ridge height was 5.49mm on anterior 1/4, 9.16mm on middle, 16.72mm on posterior 1/4 line. 6. The correlation coefficient(=r) between denture bearing area and A-P ridge length was 0.83 in the upper jaws and 0.75 in the lower jaws. The corelation between denture bearing area and AP ridge length was statistically significant, but, between denture bearing area and A-P ridge length and between A-P ridge length and the most posterior ridge width was not statistically significant in both jaws. 7. Alveolar ridge forms were classified into three(ovoid, "u" shape, and "v"shape) categories. In the upper jaws, ovoid was 66%, "u" shape was 24%, and "v" shape was 10%, in the lower jaws, ovoid was 66.7%, "u" shape was 20%, and "v" shape was 13.3%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.5
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• pp.616-621
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• 2017

The objective of this study was to investigate the physicochemical properties of domestic strong wheat flour (DSWF). Three commercial DSWFs (D1, D2, and D3) were compared with imported strong wheat flour (ISWF). DSWFs had higher moisture content, crude protein content, lightness, and whiteness than ISWF. DSWFs showed lower solvent retention capacity and water absorption index than ISWF. DSWFs also showed significantly higher water solubility index than ISWF (P<0.05). Setback values by rapid visco analysis were significantly higher in D1 and D2 than in ISWF and D3, which means ISWF and D3 were better in retarding retrogradation. Differential scanning calorimetry results showed that ISWF required 6.2 J/g of energy for phase transition, whereas DSWFs needed 6.67~7.13 J/g. The farinograph results showed that ISWF had higher water absorption, longer dough stability time, and significantly higher softening of dough at 20 min than DSWF (P<0.05). Dough resistance and extensibility were higher in ISWF than in DSWFs.

• Journal of Radiation Protection and Research
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• v.40 no.1
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• pp.65-72
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• 2015

The basic concepts of radiation-induced skin damage have been established, the biological mechanism has not been studied. In this study, we have examined the effects of gamma rays on skin injury and cyclooxygenase(COX)-2 expression. Gamma irradiation induced clinicopathological changes in a dose- and time-dependent manner in mini-pig skin. The histological changes were consistent with the changes in gross appearance at 12 weeks after irradiation. After three days' irradiation, apoptotic cells in the basal layer were found more frequently in irradiated skin than in normal skin, with the magnitude of the effect being dose-dependent. The thickness of the epidermis transiently increased 3 days after irradiation, and then gradually decreased, although changes in the epithelial thickness of the irradiated field were not observed with irradiation doses over 50 Gy. In the epithelium, there was an initial degenerative phase, during which the rate of basal cell depletion was dependent on the radiation dose (20-70 Gy). One week after irradiation, COX-2 expression was mostly limited to the basal cell layer and was scattered across these cells. High COX-2 expression was detected throughout the full depth of the skin after irradiation. The COX-2 protein is upregulated after irradiation in mini-pig skin. These histological changes associated with radiation exposure dose cause the increased COX-2 expression in a dose-dependent fashion.

• The KIPS Transactions:PartC
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• v.10C no.7
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• pp.891-898
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• 2003

This paper analyzes and proposes a scheme that improves the performance of the RTP that is developed to support the end-to-end transmission function and QoS monitor function for real-time multimedia data transmission. Although the existing RTP module supports real-time transmission, it has some problems in guaranteeing QoS parameters. To solve this problem, we propose a new Selective Repeat Adaptive Rate Control (SRARC). The SRARC can support QoS by referring to the data transmission status from the client and then classifying the network status into three levels. It selectively transmits multimedia data and dynamically controls transmission rates based on such information as bandwidth, packet loss rate, and latency that can be calculated in data transfer phase. To verify the SRARC, we implement it in real local area networks and compare the QoS parameters of the SRARC with those of the SR and RTP By the experimental results, the SRARC shows better performance in the aspects of bandwidth usage rate, packet loss rates, and transmission delays than the existing RTP schemes.