• Journal of the Mineralogical Society of Korea
• /
• v.27 no.3
• /
• pp.115-124
• /
• 2014

In order to leach Au and Ag from gold-silver bearing sulfide concentrate, the sulfide concentrate was ground in a ball mill for a dry pre-treatment and a wet pre-treatment process. Mineralogical studies and thiourea leaching experiments were carried out with the pre-treated sulfide concentrate. The results of the pre-treatment with the concentrate samples showed the mean particle size and iso-electrical potential was smaller in the dry pre-treatment sample than in the concentrate sample, and the contents was lower in the wet pre-treatment sample than in the dry pre-treatment sample. In XRD analysis, amorphous properties were only shown in the wet pretreatment sample. The results of the concentrate sample leaching experiments showed that the best Au, Ag leaching parameters were when the addition of thiourea was at a 1.0 g concentration, ferric sulfate was 1.0 M, sulfuric acid was 2.0 M and the leaching temperature was at $60^{\circ}C$. The Au, Ag leaching rate was always much greater and faster with the wet pre-treatment samples than with the dry pre-treatment samples. Accordingly, it is expected that more Au, Ag can be leached in an eco-friendly methodology using wet pre-treatment. The pre-treatment could be improved with an optimized grinding additive reagent and through researching grinding time in future non-cyanide processes.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.11 no.3
• /
• pp.63-76
• /
• 2016

The purpose of this study was to develop index about the sixth industrial entrepreneurs to establish the spirit and measuring the sixth industrial entrepreneurship for groups successfully led to the sixth industry of agriculture, which is actively being conducted in recent years aimed at rural stimulate the economy. Enlighten the value of rural resources, production, processing, in a sixth industry establishment that has a characteristic of fusion distribution and tourism in addition to the elements of the entrepreneurship that has been emphasized in the traditional establishment, the more diverse entrepreneurship element has been requested. In this study, to derive the traditional entrepreneurship of the components and the sixth industry entrepreneurship component through literature research, through interviews with experts of the sixth industry, an important element of the entrepreneurship that is required in the field It was derived. Based on the derived results, set the index of the sixth industry entrepreneurship, it was conducted a questionnaire survey of sixth industry workers. Through analysis of the navigation factors, to evaluate the measurement and indicators of relevance, factors that have been set through the results literature study and interviews of exploratory factor analysis it was found that has been rationally constructed. The results of this study, education and consulting for the activation of the sixth industry, would be able to take advantage of, such as in the planning of education programs for whom decide to go back to the countryside(Agro migration). In addition, to diagnose the entrepreneurship of a conventional sixth industry progress mainly, it is expected to be able to help you to proceed with the custom capability development that meets the individual needs.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.36 no.3
• /
• pp.1-8
• /
• 2008

The purpose of this study is to understand the conflicts that occurred in the rural village's joint management project. This study examined the perception of conflicts among people working in agricultural related fields. A questionnaire survey was given to collected data from people who participated in nation-wide resrvice training course programs. The content of the questionnaire consisted of the factors of conflict in a rural village and the details recognized by general farmers. The data was collected from October 15 to 23, 2007. 206 samples were used for final analysis from a total of 240 samples. Frequency analysis and T-test between variables were conducted by SPSS 14.0. The results suggest that farmers have a negative perception of the business partnership. Proposal for business partnerships should be avoided because of the conflicts between partners. Accordingly, as farmers don't recognize that their joint project is a business partnership, the likehood of a conflict in the agricultural joint business operation and management is contained. Conflicts mainly exist between a village leader and villagers. The main reasons for conflicts are a lack of interest and lack of communal homogeneity, and lack of methodology to share the benefit of business. It will be necessary to understand the aspects of future conflicts in order to manage joint projects ill agricultural experience villages.

• Journal of Microbiology and Biotechnology
• /
• v.16 no.12
• /
• pp.1919-1927
• /
• 2006

Tumor cells genetically engineered to secrete cytokines are effective in tumor therapy, but various unexpected side effects are observed, which may result from the bulk activation of various bystander cells. In this study, we tested tumor vaccines expressing various membrane-bound forms of IL-2 (mbIL-2) on MethA fibrosarcoma cells to focus antitumor immune responses to CTL. Chimeric forms of IL-2 with whole CD4, deletion forms of CD4, and TNF were expressed on the tumor cell surface, respectively. Tumor clones expressing mbIL-2 or secretory form of IL-2 were able to support the cell growth of CTLL-2, an IL-2-dependent T cell line, and the proliferation of spleen cells from 2C TCR transgenic mice that are responsive to the $p2Ca/L^d$ MHC class I complex. Expression of mbIL-2 on tumor cells reduced the tumorigenicity of tumor cells, and the mice that once rejected the live IL-2/TNF tumor clone acquired systemic immunity against wild-type MethA cells. The IL-2/TNF clone was inferior to other clones in tumor formation, and superior in the stimulation of the CD8+ T cell population in vitro. These results suggest that the IL-2/TNF clone is the best tumor vaccine, and may stimulate CD8+ T cells by direct priming. Expression of IL-2/TNF on tumor cells may serve as an effective gene therapy method to ameliorate the side effects encountered in the recombinant cytokine therapy and the conventional cytokine gene therapy using the secretory form of IL-2.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.46 no.9
• /
• pp.1045-1052
• /
• 2017

In this study, a battery of genetic-toxicity studies on corn silk extract with high maysin content were performed according to internationally accepted protocols. In a mutation test using Salmonella Typhimurium TA1535, TA1537, TA98, and TA100, the number of mutant colonies did not significantly increase up to a maximum concentration of $5,000{\mu}g/plate$ in the presence or absence of the S9 metabolic activation system. In the chromosome aberration test using Chinese hamster lung fibroblasts, negative results were observed in the concentration up to $1,250{\mu}g/mL$ of corn silk extract. In the micronucleus test using ICR mice, incidence of polymorphonuclear erythrocytes with a maximum concentration of 2,000 mg/kg corn silk extract did not show any significant difference compared to the negative control group. Based on these results, the test substance, con silk extract, did not influence genotoxicity.

• Journal of Korean Society of Rural Planning
• /
• v.26 no.1
• /
• pp.23-38
• /
• 2020

This study is aimed at the deduction of the important priority factors by setting the comprehensive rate in each of the economy, sociability and environmental areas for the sustainable development of fishing villages. As the research methods, review of domestic and overseas literature and Delphi questionnaire survey on experts, and hierarchical structure analysis were executed. Accordingly, this study is aimed at providing the basic data at the time of establishing plans by assessing the level of importance and priorities for each item through the deduction of the elements necessary for the fishing village plan. Key results of the study are as follows. First, as the results of review of domestic and overseas literature related to sustainability indices of fishing villages, a total of 50 items in the areas of economy, sociability and environment were deduced. Second, validity for each area was confirmed through Delphi questionnaire survey on experts. Third, as the results of factor analysis conducted on the basis of the hierarchical structure analysis for detailed items for each sector, 3 factors in the economic area, 2 factors in the social area and 3 factors in environment area were deduced. Fourth, as the results of the relative importance of the higher tiers, economic sector (0.528) displayed results that are more than 2 times higher than the social (0.261) and environmental (0.212) sectors. Establishment of foundation for independent competition (0.105), balanced development of small fishing village (0.086) and population engaged in economic activities in comparison to the fishing village population (0.077) were analyzed as the most important detailed items. Based on these results, experts pointed out that the economic sector is most important for the sustainable development of fishing village and, in detail, priority must be placed on the balanced development on the basis if the extent of independence of the fishing villages, and emphasized activation of residents engaged in economic activities in fishing villages in order to support them. That is, in order to increase the level of independence of the fishing villages, it was determined that there is a dire needs for expansion of diversified specialized businesses and infrastructural facilities through agreement by the residents capable of economic activities, and means of activating fishing villages through securing of budget at the local autonomous government level to provide support for the residents.

• Korean journal of food and cookery science
• /
• v.27 no.5
• /
• pp.589-597
• /
• 2011

This study was performed to evaluate the physiological and sensory properties of breads with different ratios of persimmon peel. Moisture activation of the bread loaf decreased as storage period increased with a smaller range of decrease in the persimmon peel added group. The amount of weight increased, and volume fell to some degree. Adding persimmon peel increased the RVA temperature, whereas maximum decreased. The color change during storage was due to the addition of control and 4% in group a values except there was no significant difference. As the result of measurements using a texture analyzer, hardness, springiness, cohesiveness, gumminess, and chewiness properties decreased. The sensory test results revealed that the 4% and 6% added persimmon peel bread was the best.

• Microbiology and Biotechnology Letters
• /
• v.40 no.4
• /
• pp.414-418
• /
• 2012

The quantity of research on microbial fuel cells has been rapidly increasing. Microbial fuel cells are unique in their ability to utilize microorganisms and to generate electricity from sewage, pig excrement, and other wastewaters which include organic matter. This system can directly produce electrical energy without an inefficient energy conversion step. However, with MFCs maximum power production is limited by several factors such as activation losses, ohmic losses, and mass transfer losses in cathodes. Therefore, electron acceptors such as nitrate and ferric ion in the cathodes were utilized to improve the cathode reaction rate because the cathode reaction is very important for electricity production. When 100 mM nitrate as an electron acceptor was fed into cathodes, the current in single-cathode and dual-cathode MFCs was noted as $3.24{\pm}0.06$ mA and $4.41{\pm}0.08$ mA, respectively. These values were similar to when air-saturated water was fed into the cathodes. One hundred mM nitrate as an electron acceptor in the cathode compartments did not affect an increase in current generation. However, when ferric ion was used as an electron acceptor the current increased by $6.90{\pm}0.36$ mA and $6.67{\pm}0.33$ mA, in the single-cathode and dual-cathode microbial fuel cells, respectively. These values, in single-cathode and dual-cathode microbial fuel cells, represent an increase of 67.1% and 17.6%, respectively. Furthermore, when supplied with ferric ion without air, the current was higher than that of only air-saturated water. In this study, we attempted to reveal an inexpensive and readily available electron acceptor which can replace platinum in cathodes to improve current generation by increasing the cathode reaction rate.

• Journal of Family Resource Management and Policy Review
• /
• v.16 no.2
• /
• pp.187-210
• /
• 2012

Pumasi and Cooperative Child Care Sharing have had positive results among participants and show possibilities of spreading out to the community in general. However, performance was not proved where it is clarified, and the experience of 23 local Healthy Family Support Centers have that ran the demonstration project were unable to be collected. It is the point of time when the initial backing up is important but the centers do not have the systematic support. Therefore, this research presents an effective management plan through qualitative research involving Pumasi participants and person in charge. The operation strategies by the stage of the project were as follows: First, in the beginning stage, the person in charge establishes the target and vision of the project. Second, when comprising the Pumasi team, it was necessary to consider their characteristics according to the team organization subjects. Third, it is necessary to extend the turn-off time and provide many programs so that the various populations can participate. Fourth, in the advertising step, word of mouth and individual contact needs to be utilized. Fifth, in a medium or small city or an urban-rural complex area, the person in charge should support the participants' Pumasi activities. Sixth, various programs such as a passive and active parent education program and Pumasi education program for the leader needs to be provided for the activation of Pumasi activities. Lastly, a cooperative child care sharing location needs to be constructed by the duality system of the base space and outer space. In this location, the inside play space for the children is essential.

• Korean Journal of Social Welfare
• /
• v.55
• /
• pp.283-307
• /
• 2003

The social services for the elderly have been expending in order to respond to the rapid speed of aging. However, low utilization, exclusion and duplication have been pointed out as significant problems in service utilization of the elderly. This study tried to find out the utilization patterns of social services for the elderly: what kinds of and how many social services the elderly receive from what kinds of and how many organizations, and factors influencing utilization of the social services. It surveyed the entire population of the public assistance recipient elderlies at Kyonggi province in 1999. The results show that duplication is not so significant problem as the low utilization of social services. However, the fact that more than forty five percent of the elderly receives social services from more than two organizations requires the efforts for service linkage and coordination in social service delivery system. The factors, which have relatively big influence on the number of organizations which the elderly use for each social service, were sex and age among the predisposing factors, "living alone" and place for residency among the enabling factors and the number of illness, Activities of Daily Living, Instrumental Activities of Daily Living and inconvenience of housing among the needs factors. These results call for expansion of social services for the elderly especially in the way of achieving distribution balance between the rural and urban area and activation of case management practice and local association of social service delivery agencies for service linkage and coordination.