• The Korean Journal of Food And Nutrition
• /
• v.15 no.2
• /
• pp.89-96
• /
• 2002

The adsorption characteristics of sodium chloride into Ca-alginate beads have been investigated and the result were as follows: Sodium chloride uptake by Ca-alginate beads increased with time. The highest uptake volume of sodium chloride was 4.2g after 10 minutes. The uptake volume by Fe, Ca, Ba, and Sr-alginate beads was 5.6g, 4.2g, 4.2g and 4.0g, respectively but in case of Fe-alginate beads, the induced hydrogel beads were very fragile and the strength of Fe-alginate beads were weaker than Ca- and Ba-alginate beads. Mg-alginate bead was not formed and Ca-, Ba- and Sr-alginate beads had a similar uptake volume about 4.2g, respectively. The uptake volume of sodium chloride by CaCl$_2$concentration(0.1M. 0.2M and 1M), curing solution, was 4.8, 4.2g and 4.1g, respectively. The uptake volume by sodium alginate concentration(0.6%, 1% and 2%) was 2.8g, 4.0g, and 4.4g, respectively and Ca-alginate bead size was not effected in uptake sodium chloride. The uptake rate on initial sodium chloride concentration(4%, 8%, 12% and 16%) was 30%, 28%, 27% and 25%, respectively. The uptake rate on basic pH(10.0) was higher than when compared to other neutral pH(6.8) and acidic pH(4.0). The initial uptake velocity of sodium chloride from immobilization beads with salt resistant bacteria was lower than that of non-immobilization beads. The uptake rate of sodium chloride was decreased according to elongation of curing time. Reusability of Ca-alginate beads was possible but according to reutilization, the salt uptake volume of beads was also decreased. The uptake volume of sodium chloride from Doengjang by Ca-alginate beads on time course(3, 6, 12, and 24 hour) was revealed 5g, 6g, 7g and 7g, respectively.

• Journal of Nutrition and Health
• /
• v.9 no.1
• /
• pp.76-83
• /
• 1976

The aims of this study are, 1) to describe the attitudes of the community towards each food item and 2) to provide the information necessary for the solution of nutritional problems due to the different food intake of the community. This study is based on the Food Consumption Survey conducted by the Ministry of Health and Social Affairs in a series of National Nutrition Survey in August, 1973. The sample included 8 communities, in which 160 households were selected at random for this study. The procedures and methods used in this study to compute the acceptability index were adopted from the study of H. Toyokawa, University of Tokyo. Food attitudes of the sample communities are clear in terms of the mean acceptability index which is presented in Table 3. The following order is indicative of the relative strength of acceptability of the respective food items: 1. Seasonings (-1.20) 2. Oils and fats (-1.12) 3. Pulses(- .60) 4. Processed vegetables (- .45) 5. Seaweeds (- .32) 6. Sugars (- .19) 7. Fresh vegetables (- .15) 8. Rice (- .13) 9. Cereals and grain products (- .07) 10. Starchy roots (- .06) 11. Fresh fish and shells (.44) 12. Processed fish and shells (.56) 13. Eggs (1.06) 14. Fruits (1.26) 15. Meats and poultry (1.33) 16. Milk and milk products (2.87) There are highly significant difference in the acceptability index between food items and the mean intake of rice, cereals and grain products, pulses, starchy roots, processed vegetables, fruits, sugars, seaweeds, seasonings, meats and poultry, eggs, fresh and shells, and oils and fats between the communities at the .01 level of significance.

• Journal of the Mineralogical Society of Korea
• /
• v.15 no.2
• /
• pp.104-113
• /
• 2002

The sorption of Cd$^{2+}$ on calcite was studied in aqueous solutions of several electrolytes. The Cd$^{2+}$ concentration, 10$^{-8}$ M, was kept well below saturation with respect to CdCO$_3$(s). Sorption behavior of Cd$^{2+}$ in different ionic strengths of NaClO$_4$solutions shows that sorption is independent of ionic strength. This result suggests that Cd$^{2+}$ sorption on calcite surface is of a specific nature, and adsorption is controlled by an inner-sphere type of surface complex. Two stages in the sorption behavior could be identified: an initial rapid uptake, followed by slower uptake reaching a maximum steady state by 145 hrs. No evidence was observed for surface precipitation, although it can not be entirely ruled out. Desorption of Cd$^{2+}$ from the calcite surface after resuspension into Cd-free solution is initially very rapid, but depends partly on the previous sorption history. Desorption behavior of Cd$^{2+}$ show that an initial rapid desorption followed either by slow uptake reaching a maximum, as in the adsorption experiments, or slowing desorption to reach a steady state minimum. This irreversible behavior of Cd$^{2+}$ sorption and desorption may act as one of the controls for regulating the mobility of dissolved Cd$^{2+}$ natural aqueous systems. Calculated adsorption partition coefficients suggest that overall sorption and desorption process in the concentration range are controlled by d single mechanism.ingle mechanism.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.6C
• /
• pp.648-658
• /
• 2003

As the usage of image/video contents increase, a security problem for the payed image data or the ones requiring confidentiality is raised. This paper proposed an image encryption methodology to hide the image information. The target data of it is the result from quantization in wavelet domain. This method encrypts only part of the image data rather than the whole data of the original image, in which three types of data selection methodologies were involved. First, by using the fact that the wavelet transform decomposes the original image into frequency sub-bands, only some of the frequency sub-bands were included in encryption to make the resulting image unrecognizable. In the data to represent each pixel, only MSBs were taken for encryption. Finally, pixels to be encrypted in a specific sub-band were selected randomly by using LFSR(Linear Feedback Shift Register). Part of the key for encryption was used for the seed value of LFSR and in selecting the parallel output bits of the LFSR for random selection so that the strength of encryption algorithm increased. The experiments have been performed with the proposed methods implemented in software for about 500 images, from which the result showed that only about 1/1000 amount of data to the original image can obtain the encryption effect not to recognize the original image. Consequently, we are sure that the proposed are efficient image encryption methods to acquire the high encryption effect with small amount of encryption. Also, in this paper, several encryption scheme according to the selection of the sub-bands and the number of bits from LFSR outputs for pixel selection have been proposed, and it has been shown that there exits a relation of trade-off between the execution time and the effect of the encryption. It means that the proposed methods can be selectively used according to the application areas. Also, because the proposed methods are performed in the application layer, they are expected to be a good solution for the end-to-end security problem, which is appearing as one of the important problems in the networks with both wired and wireless sections.

• Journal of the Microelectronics and Packaging Society
• /
• v.27 no.2
• /
• pp.39-44
• /
• 2020

Recently, numerous researches are being conducted in flexible substrate to apply to wearable devices. Particularly, Conductive substrate researches that can implement the wearable devices on clothing are massive. In this study, we formed fiber substrate spraying CNT and Pd mixed solution on it and plated metal layer with electroless plating. Used SEM equipment and EDS analysis to analysis structure of the plated fiber substrate and discovered Ni layer was created. For check electrical properties, mapping was performed to check surface resistance and distribution of resistance of electroless plated fiber substrate with 4-point probe. It was confirmed that conductivity was improved as the duration of electroless plating was increased, and it was found that distribution of resistance by surface location was uniform. Changes in resistance due to mechanical stress were measured through tensile, bending, and twisting tests. As a result, it was confirmed that resistance change of flexible substrate gradually disappeared as plating time increased. Using UTM (Universal testing machine), it was analyzed mechanical properties of the electroless plated substrate with respect to changes in plating time were improved. In the case of conductive fiber substrate in which electroless plating was performed for 2 hours, tensile strength was increased by 16 MPa than fiber substrate. Based on these results, we found that Ni-CNT-Fabric flexible substrate is adequate for clothing-intergrated conductive substrate and we positively expect that this experiment shows flexible substrate can adapt to and develop not only a wearable device technology but also other fields needing flexibility such as battery, catalyst and solar cell.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.27 no.2
• /
• pp.161-174
• /
• 2011

The purpose of this study was to evaluate the effect of ethanol addition on efficacy of two-step total-etch adhesive under over-wet condition by measurement of remaining volatile part (RVP), microtensile bond strength (${\mu}TBS$), and degree of conversion (DC). Two-step total-etch adhesive, Optibond Solo Plus (Kerr, Orange, USA), was used. Experimental groups were divided into 8 groups: Group 1 (only 10 ${\mu}l$ adhesive), Group 2 (mixture of 3 ${\mu}l$ distilled water and 10 ${\mu}l$ adhesive), From Group 3 to Group 8 (mixture of 3 ${\mu}l$ distilled water, 10 ${\mu}l$ adhesive, and ethanol added in 1 ${\mu}l$ increment from 1 ${\mu}l$ to 6 ${\mu}l$). The mixtures were placed on slide glass and evaporated for 10 s, 30 s, and 60 s by air-drying. The weight of RVP was measured by precision weight. Same procedures were performed for ${\mu}TBS$ test and measurement of DC. The condition of mixed solution was observed under light microscope. For RVP weight, the weights of experimental groups except for group 1 decreased with the increase of air-drying time (p<0.05). The DC increased with the increase of air-drying time in only group 5 and 6 (p<0.05). The ${\mu}TBS$ increased with the increase of air-drying time in group only 5, 6, and 7 (p<0.05). The phase separation was examined and water blisters were diminished with the increase of air-drying time in group 5, 6, 7, and 8. Within the limits of this study, ethanol additionally applied to adhesive decreased RVP and increased DC and ${\mu}TBS$ under over-wet condition. It was shown that the addition of ethanol to two-step total-etch adhesive under over-wet condition would remove water and increase the efficacy of adhesive.

• Journal of the Korean Wood Science and Technology
• /
• v.9 no.3
• /
• pp.7-15
• /
• 1981

A Japanese larch has been reforested very much in Korea, but it is not used as a wood resources for paper pulp by now. So this study is carried out to utilize the larchwood for paper pulp manufacture through the Asplund pulping process. The experiment on increasing in the brightness of the pulp is made through the addition of $MgSO_4$, $ZnSO_4$, $Al_2(SO_4)_3$, and KI as a cellulose stabilizer in chip treatment with caustic soda which is followed by high-temperature defibration and conventional peroxide bleaching (5% NaOH plus 2% additive salt per wood in cold pretreatment), or in high-consistency (30%) pulp bleaching of hydrogen peroxide and peracetic acid (100% acitve oxygen per lignin) for conventional one. The results obtained are as follows: 1. The solution of 0.5% additive salts had different pH by the sort of bases that was pH 5.7 in $MgSO_4$, liquor, pH 4.9 for $ZnSO_4$, and pH 2.9 for $Al_2(SO_4)_3$, and in the precepitation of bases which ranged to pH 6-13 for $MgSO_4$, pH 5-12 for $ZnSO_4$, and pH 3-10 for $Al_2(SO_4)_3$. 2. The cellulose stabilizer affective in high-consistency peroxide bleaching was KI, $MgSO_4$, and $ZnSO_4$, but has made a little improvement in de lignification and brightness of pulp in comparison with no addition. 3. The higher alkalinity in the chip treatment has made the higher strength and brightness of larchwood Aspiund pulp instead of downing the pulp yield. And the effective compound for cellulose stabilizer in caustic soda pretreatment of chip was $ZnSO_4$, $Al_2(SO_4)_3$ and KI in order for the conventional peroxide bleaching after Asplund pulping. 4. Therefore, the more effective additives for cellulose stabilization in high-temperature defibration of larchwood suppose to be $ZnSO_4$, $Al_2(SO_4)_3$, and KI, while KI and $MgSO_4$ for peroxide bleaching.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.31 no.4
• /
• pp.113-122
• /
• 2013

In this study, the traditional structure of the impact on the stability analysis. Korean traditional landscape architecture column space of stonework stable composition as the foundation of the fence for a long time been known to fall down and not maintained. The destination of research Ohgokmun Damyang Soswaewon fence which is in harmony with nature is one of the traditional structures that affect its shape without being kept so far came true. This includes our ancestral wisdom and that wisdom can guess guesswork. But I let the traditional reproduction incidence structures frequently. This deviation from the traditional method of construction application of shorthand stand. Thus, the subject of this study, the factors that do not fall down fences Ohgokmun solution is to indirectly gain the weak. In addition, epidemiological studies and the methods of calculation of the inferred physical examination, the results of the analysis were derived through the following. First, the internal factors of the fence Ohgokmun constituting the structural member and the coupling of the scheme. 1) based on stable ground. Greater role in the country rock The fact that the settlement will have no symptoms. 2) to minimize the friction caused by hydrological water to remove the two-pronged process through stone work building form and menu sustaining power in hydrology and flooding made against the bypass channel. 3) due to the load bearing capacity and durability to withstand the strength of the material and the construction of structures in the form of a dispersion of power between each individual to maximize the process of getting traction was applied. Second, external factors Ohgokmun fence the results obtained through the calculation of the dynamics of repair, is greatly affected by the wind and the water gate of the fence, but the action of the structural stability of the lack of power that hurt enough conclusion. In this study, the results of the structure of internal and external influence as well through the structure can be viewed as composed consisting. However, over the next follow-up in terms of climate and environmental factors due to the fact that the fall might.

• Korean Journal of Social Welfare Studies
• /
• v.44 no.3
• /
• pp.177-206
• /
• 2013

The Korean government has implemented the senior employment policy as a direct job creation policy since 2004. A realistic discussion of policy alternatives and orientation for this has been given little attention even though senior employment policy has been carried out for the last 10 years and it will be expanded next year. This study tries to examine active labor market policy especially focusing on direct job creation programs and policies for the disadvantaged low-income elderly in OECD countries, and then it suggests some developmental alternatives for senior employment policy based on the study's results. The main results from this analysis are summarized in two points. Firstly, except pension policies, employment policy for older workers in the OECD countries is highly proportional to the tackling of objective factors reducing the demand for older workers (wage subsidies, reduced social security contribution rate etc). And the strategies of improving employability have not been relatively important and direct job creation policy has been marginal. Secondly, employment support policies for the low-income elderly can be divided into three types: support for the low-income elderly, alleviating early retirement and support for full employment according to the criteria which are determined by policy objectives and the social economic index. Korea's employment support policies belong to the type of direct job creation among them. This seems to be due to the fact that the rate of elderly poverty is extremely high and an income security system has not been developed in Korea. However, the policy objective is still uncertain. Therefore, this policy needs to set up clear objectives and establish a proper system for the achievement of its goals. If we focus on the strength of its employment characteristics, we need to modify the policy's plan in the perspective of labor market policy. But if we intend to keep both of the current objectives, it is better for this policy to be divided into two parts: social participation and income supplements. Or it also may be a solution to transform the system into an employment service, a training system which supports participants to move into unsubsidized jobs such as SCSEP in the U. S.

• Journal of Conservation Science
• /
• v.34 no.6
• /
• pp.595-604
• /
• 2018

In this study, in a bid to develop natural bioadhesives for paper craft, the hanji industry, and preserving cultural assets, complex polysaccharides were extracted from brown and red algae and used as an ingredient in adhesives. Brown algae include sea trumpet, kelp, sea oak, and sea mustard, whereas red algae include Pachymeniopsis elliptica agar-agar weed, Gloiopeltis tenax, and hunori. The polysaccharides were extracted after transforming them from non-aqueous Ca complexes contained in each of the brown and red algae into water-soluble polysaccharides containing alkali metals with a solubility level of 1. and extracted Subsequently, only the polysaccharides were extracted using alcohol precipitation. The adhesion tensile strengths of kelp, a brown algae, and Pachymeniopsis elliptica, a red algae, were 21.58 and 32.99 kgf, respectively. They thus demonstrated better adhesion than that of solid glue products such as water plants (18.45 kgf) and glue sticks (20.45 kgf). The extraction yield of these polysaccharides is supposed to be determined according to their extracted environments; however, no difference in adhesion strength was seen. Further, it was found that the shapes of polysaccharides were determined by their growing environment instead of extraction environment. Use of multi-step alcohol precipitation method during extraction enabled the removal of the constituents except protein and other polysaccharides, thereby demonstrating a stable outcome without cultivation of mold. Furthermore, there was no occurrence of mold even after production of the adhesives by the simple solution method, which demonstrates the adhesive's potential as an environment-friendly adhesive material.