• Journal of the Korea Institute of Building Construction
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• v.12 no.1
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• pp.54-63
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• 2012

The purpose of this study is to examine the potential for reducing the environmental load and $CO_2$ gas when cement is produced by using cement substitutes. These substitutes consisted of blast furnace slag, red mud and silica fume, which were industrial by-products. The most optimum mix was derived when alkali accelerator was added to low carbon inorganic composite mixed with industrial by-product at room temperature. It is determined that hardened properties and the results of compressive strength tests changed based on CaO content, Si/Al, the mixing ratio and the amount of alkali accelerator, curing conditions and W/B. The results of test analysis suggest that the optimum mix of low carbon inorganic composite is CaO content 30%, Si/Al 4, the mixed ratio of alkali accelerator $(NaOH:Na_2SiO_3)$ 50g:50g, the amount of alkali accelerator 100g and W/B 31%. In addition, if contraction is complemented, low carbon inorganic composite with superior performance could be developed.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.568-576
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• 2012

Baksulgi with various sugar substitutes was prepared and characterized for physicochemical and sensory qualities. The 10% sugar in a control baksulgi was replaced with 16.1% glucose, 13.3% erythritol, 10.2% xylitol, 0.2% stevioside (enzymatically modified stevia 100%), 0.05% aspartame, or 1.2% sucralose. Instrumental and sensory analyses indicated that the baksulgi with glucose was significantly different in color from the others, which was attributed to high susceptibility to browning reaction of the glucose. Baksulgi with aspartame showed significantly lower pH than that of control baksulgi, suggesting that the aspartame might have been hydrolyzed into its constituent amino acids under elevated steaming temperature. A sensory evaluation revealed that baksulgi with sucralose or xylitol was comparable to the control baksulgi in all sensory characteristics. However, the baksulgi with sucralose showed appreciably increased hardness with increased storage time at $4^{\circ}C$, partially due to the anhygroscopic property of sucralose.

• The Korea Journal of Herbology
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• v.22 no.3
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• pp.15-26
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• 2007

Objectives : The purpose of this study is to analyze the origin plants, the habitat and the characteristics of the origin-plants of the medicine herbs belong to Araceae. Methods : To achieve the purpose of this study 48 bibliographies about 4 kinds of herbs belong to Araceae were examined. The examination was focused on the origin plants, habitat, the efficacy. Standing on this analysis the list and characteristics of the origin-plants were presented. Results : The results indicated that 1. In the original plants of 4 kinds of herbs, there were 27 species of scientific name totally, 25 species belonged to Araceae, and 2 species didn't. The origin plants of Pinelliae rhizoma were 3 species of different family plant, 16 species for Arisaematis Rhizoma, 2 species for Typhoni Rhizoma, and 6 species for Acori Graminei Rhizoma. 2. In the view of its authenticity, there was one kind of genuine species, 2 species of substitutes in the origin plants of Pinelliae Rhizoma, 14 kinds of genuine species, 2 species of substitutes in the origin plants of Arisaematis Rhizoma, and Whole origin plants of Typhoni Rhizoma, Acori Graminei Rhizoma were genuine species. 3. According to the habitat, there were 15 species distributed in Korea, China and so on. And 16 species were distributed in Korea, 25 species were of foreign origin. 1 species was unknown. 4. The each efficacy of origin plants were reported in the main subject Conclusions : Among the 4 medicinal herbs in the commonly using family Araceae, there were 27 origin plants(25 species belong to Araceae, and 2 species doesn't), so the number of origin plants are almost 6.75 times compared with the cases of the herbal name. Also, according to the habitat, approximately 59.3% of origin plants were producted in Korea, and approximately 92.6% of origin plants were of foreign origin.

• Journal of Korea Multimedia Society
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• v.12 no.11
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• pp.1563-1571
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• 2009

In this paper, we propose a new boundary matching method for the temporal error concealment and a post processing algorithm for perceptual quality improvement of the concealed frame. Temporal error concealment is a method that substitutes error blocks with similar blocks from the reference frame. In conventional H.264/AVC standard, it compares outside pixels of erroneous block with inside pixels of reference block to find the most similar block. However, it is very possible that the conventional method substitutes erroneous block with the wrong one because it compares only narrow spatial range of pixels. In this paper, for substituting erroneous blocks with more correct blocks, we propose enhanced boundary matching method by comparing inside and outside pixels of reference block with outside pixels of erroneous block and setting up additional candidate motion vector in the fixed search range based on maximum and minimum value of candidate motion vectors. Furthermore, we propose a post processing method to smooth edges between concealed and decoded blocks without error by using the modified deblocking filter. We identified that the proposed method shows quality improvement of about 0.9dB over the conventional boundary matching methods.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.880-886
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• 2007

Ensiled or oven-dried green tea by-products (GTB) were evaluated in goats for their nutritive potential as protein feedstuffs based on in vitro and in vivo digestibility. To elucidate the effects of tea tannin on in vitro digestibility, polyethylene glycol (PEG) was used as a tannin binding agent. Both ensiled and dried GTB contained 31.9 to 32.6% of crude protein (CP) on a dry matter (DM) basis. Phenolics and tannins in soybean meal and alfalfa hay were low or not detected, but they were high in both ensiled and dried GTB (7.3-10.1% DM as total extractable tannins). In vitro protein digestibility in the rumen ranked: soybean meal>alfalfa hay cube>ensiled GTB = dried GTB. The protein digestibility post-ruminally of these feedstuffs showed a similar trend to that in the rumen, but the digestibility of ensiled GTB was significantly higher than that of dried GTB. Addition of PEG improved the in vitro protein digestibility of both kinds of GTB in the rumen and post-ruminally, indicating that tannins suppressed the potential protein digestibility of GTB. The increased protein digestibility by PEG addition was not significantly different between ensiled and dried GTB in the rumen, but the percentage increment of ensiled GTB was higher than dried GTB post-ruminally. In the in vivo digestibility trial, ensiled and dried GTB were offered to goats as partial substitutes for soybean meal and alfalfa hay cubes. Offering both GTB to goats as 5-10% on a DM basis did not affect nutrient digestibility, ruminal pH, volatile fatty acids, and ammonia concentration. However, the eating time of the GTB-incorporated diet was longer than that of the basal diet. It took 1.4 and 1.6 times longer than the control diet, to eat the diet completely when GTB silage was offered at 5 and 10% levels, respectively, of the total diet. These results show that ensiled and dried GTB are useful as partial substitutes for soybean meal and alfalfa hay cubes for goats with respect to nutritive value. Because of lessened palatability, it is recommended that GTB be incorporated into the diet at 5% on a DM basis.

• Journal of Korean Neurosurgical Society
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• v.50 no.4
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• pp.348-356
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• 2011

Objective : The safety and efficacy of various fusion substitutes in pyogenic osteomyelitis has not been investigated. We evaluated and compared the cadaveric allograft and titanium cages used to reconstruct, maintain alignment and achieve fusion in the management of pyogenic spinal infection. Methods : There were 33 patients with pyogenic osteomyelitis underwent fusion in this study. Fifteen of the 33 patients were operated on by fusion with allografts (cadaveric patella bones) and 18 of those were operated with titanium mesh cages filled with autologous cancellous iliac bone. After the affected disc and vertebral body resection with pus drainage, cadaveric allograft or titanium cages were inserted into the resected space. Posterior transpedicular screw fixation and rod compression in resected space, where cadaveric allograft or titanium cages were inserted, was performed to prevent the malposition in all patients except in 1 case. Recurrent infection was identified by serial erythrocyte sedimentation rate and cross reactive protein follow-up. Osseous union and recurred infection available at a minimum of 2 years following operation was identified. The amount of kyphosis correction and the subsidence were measured radiographically. Results : Spinal fusion was achieved in 29 of 33 patients. In the cadaveric allograft group, 93.3% of patient (14 of 15) showed the osseous union while 83.3% of patient (15 of 18) in the titanium cage group showed union. Subsidence was noted in 12 of the patients. Twelve patients (36.3%) showed unsettling amounts of subsidence postoperatively whereas 46.6% of patients in the cadaveric allograft group and 37.7% of patients in the titanium cage group showed similar subsidence, respectively. There were statistical difference in the fusion rate (p=0.397) and subsidence rate (p=0.276) between the two groups. There was significant statistical difference in the postoperative improvement of segmental kyphosis between the two groups (p=0.022), that is the improvement in sagittal alignment was greater in the titanium cage group than in the cadaveric allograft group. There was no case of recurred infection. Conclusion : The cadaveric allograft and titanium cages are effective and safe in restoring and maintaining sagittal plane alignment without increased incidence in infection recurrence in pyogenic osteomyelitis. The postoperative improvement of segmental kyphosis was better in the cage group.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.626-632
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• 2008

The purpose of this study was to enhance gas exchange by producing hemosome, a hemoglobin microencapsulated with phospholipid of egg, and perfluorocarbone(PFC) emulsion solution. In the experiment, stable emulsion solution with 437 nm of mean particle size could be produced by Flusol-DA sonication, and shortening of emulsion time could be attained with higher stability as well. $0.8{\mu}m$ sized hemosome could be produced by microencapsulation of hemoglobin with phospholipid extracted from egg yolk. The pattern of oxygen saturation curve of hemosome was S shape, which is similar to that found in normal blood, and $P_{50}$ was measured to be 24 mmHg. The oxygen saturation in the mixed solution of hemosome and blood in 1:4(V/V%) ratio was similar to that of normal blood, and the same result was found in the mixed solution of PFC emulsion and blood in 1:4(V/V%) ratio.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.2
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• pp.18-26
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• 2000

Since the regulation of MSDS (Material Safety Data Sheets) had started from July 1996, employers were required to furnish MSDS for the chemicals in use in their workplace. However, many MSDS did not contain upright information for the chemicals, and they were not updated regularly, and were not written in the standard format required by the Industrial Safety and Health Act (ISHA). The purposes of this study were 1) to examine the reliability of MSDS for mixed solvents, 2) to provide reliable MSDS to employers or employees, 3) to find out any difficulties in implementing MSDS after the initiation, and 4) to promote regular MSDS updating and to ensure the reliability of MSDS for chemical manufacturers. To check the reliability of MSDS of mixed chemicals, 21 samples of mostly degreasing solvents were collected along with their MSDS from the work place. The samples were analyzed by gas chromatography-mass selective detector(GC-MSD). Their components were classified as saturated hydrocarbon, cyclic hydrocarbon, aromatics, and halogen containing hydrocarbon, and the amount of each class were measured. Manufacture's MSDS were compared with the actual composition of the collected samples, and further examined the reliability by checking whether the chemicals analyzed were included in the MSDS correctly. Finally, each item of MSDS was evaluated whether the MSDS correspond to the regulation required by ISHA. The results were following: 1) most of the degreasing solvents in MSDS were incorrect in their composition and contents, 2) the information in the MSDS including hazard classification, exposure level, toxicity, regulatory information were incorrectly provided, and 3) some MSDS did not disclose carcinogens in their MSDS. Continuous monitoring of MSDS was required to ensure reliability of MSDS. The Chemicals containing hydrocarbons from C10-C15 need to be tested to provide toxicity data. In addition, governmental support for providing correct MSDS was recommended to ensure reliability of MSDS. The MSDS regulation relating to the confidential business information may need to be revised to ensure reliability of MSDS.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.1
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• pp.38-50
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• 2013

Purpose: The aim of this study is to evaluate the effect and potential of electron beam (E-beam) irradiation treatment to the synthetic bony mixtures composed of hydroxyapatite (HA; Bongros$^{(R)}$, Bio@ Co., Korea) and tricalcium phosphate (${\beta}$-TCP, Sigma-Aldrich Co., USA), mixed at various ratios and of type I collagen (Rat tail, BD Biosciences Co., Sweden) as an organic matrix. Methods: We used 1.0~2.0 MeV linear accelerator and 2.0 MeV superconductive linear accelerator (power 100 KW, pressure 115 kPa, temperature $-30{\sim}120^{\circ}C$, sensor sensitivity 0.1~1.2 mV/kPa, generating power sensitivity 44.75 mV/kPa, supply voltage $5{\pm}0.25$ V) with different irradiation dose, such as 1, 30 and 60 kGy. Structural changes in this synthetic bone material were studied in vitro, by scanning electron microscopy (SEM), elementary analysis and field emission scanning electron microscope (FE-SEM), attenuated total reflection (ATR), and electron spectroscopy for chemical analysis (ESCA). Results: The large particular size of HA was changed after E-beam irradiation, to which small particle of TCP was engaged with organic collagen components in SEM findings. Conclusion: The important new in vitro data to be applicable as the substitutes of artificial bone materials in dental and medical fields will be able to be summarized.

• KDI Journal of Economic Policy
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• v.14 no.4
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• pp.107-121
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• 1992

Moonlighting or second-jobs will increase shirking of the primary job. This paper analyzes the motives for moonlighting so that the means of reducing these motives could be explored. The traditional theory claims that a worker who cannot fully realize his work potential will look to moonlighting. In a two-period model, however, the following motives are more important. The precautionary savings motive : A worker has an incentive to save for fear of losing his job and his income in the second period. The worker could save more by working more during the first period, and this additional motive for working is the precautionary savings motive. The insurance motive : When a worker is unemployed, he cannot expand his moonlighting hours according to his needs since the moonlighting hour is upward rigid. Therefore, a worker has an incentive to secure additional moonlighting hours in the first period so that quick adjustment can be made during the unemployment in the second period. Two policy measures to remove those motives for moonlighting are recommended, for these measures will enhance the productivity in the primary job. First, a firm should guarantee that there will be no layoffs in a downturn in the economy and that the employment level is adjusted to the economic states by work sharing among workers. Second, as unemployment insurance benefits compensate a portion of the income in case of unemployment, it substitutes the motives for moonlighting. A generalization of this argument can be found in Ehrlich and Becker(1972) where self-insurance(moonlighting) and market insurance(in this case, unemployment insurance) serves as substitutes. The two policy measures in the above have a spill-over effect : A decrease of labor supply in the moonlighting market will ease job search, and therefore will help those who have their primary job in the moonlighting sector.