• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.731-743
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• 2018

This study was performed to test the feasibility of thermophilic ($55^{\circ}$) co-digestion of municipal sewage sludge and food wastes. The management variables of co-digestion were the mixed ratios of municipal sewage sludge and food waste hydraulic retention times (HRTs). During the operation of thermophilic co-digestion, the reactor pH ranged from 7.0 to 7.5 and the reactor alkalinity remained above 3,200 to 4,000 mg/L as $CaCO_3$. The volatile fatty acids concentration increased as the HRT shortened from 20 days to 10 days and the mixture ratio increased to 1:4, but did not reach toxic levels for co-digestion of sewage sludge and food wastes. Methane productivity increased gradually as the organic loading rate increased. Maximum methane productivity reached 1.03v/v-d at an HRT of 10 days and at the mixture ratio of 1:4. The TVS removal efficiency decreased from 70.6% to 58.3% as the HRT shortened from 20 days to 10 days. TVS removal efficiency ranged from 57.0% to 77% during the entire operation. It is likely that thermophilic co-digestion of sewage sludge and food wastes is a very effective method both to environmentally treat food waste and to economically produce gas for energy.

• Journal of the Korean Dietetic Association
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• v.14 no.1
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• pp.51-63
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• 2008

The purpose of this study was to understand the management status of food wastes in school meal to find the effective ways that would reduce and recycle them. Data was collected using questionnaires from 223 school dietitians located in Jeonbuk area. The results were as followed : 1) Waste was managed by the dietitians(54.7%) and cook(42.2%). The waste disposal contract was made by dietitians(65.0%), executives(31.4%). Therefore, school dietitians had primary responsibilities in the waste management. 2) As disposal ways, 48.9% processed municipal solid waste and food waste together and 46.6% processed separately. 3) A half of schools(52.9%) produced food wastes weighed under 10$\sim$15kg daily and using food wastes as animal food for farms was most popular method to dispose(87.4%). 4) Reasons to have food-wastes were disliking the taste of menu(50.2%) and the inappropriate ways of dealing with remaining food(64.1%) and donating to food bank(33.6%) in order. 5) The suggested ways to reduce the food-waste was to improve on cooking method(72.2%), changing of portion size(61.0%), measuring the amount of leftover food(53.4%) and requesting cooperation to educators(52.9%). 6) The reported consequences of reducing the food waste were: lowered grocery expenses(46.2%), and inspiring students on helping environmental preservation(23.8%). Therefore, the administration should work on finding a method to reduce food-waste and a way to use these resources efficiently. It is important to induct student's attitude on recycling remaining products by using food bank via nutrition education. Dietitian also should consider to reduce the leftover of food by using a standardized recipe.

• Journal of Korea Society of Industrial Information Systems
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• v.27 no.4
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• pp.105-114
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• 2022

As the national income level is improving, housing urbanization and economic speed are progressing rapidly, household waste and food waste are rapidly increasing. The "Waste Management Act" (founded in 1991) introduced the volume-based household waste system in 1995, and even after implementation, the odor of food waste and the prompt disposal process continue to be a social problem.For this reason, the food waste recycling business is attracting attention. In this paper, regarding the role of resource recycling such as feed, compost, and other resources of food waste, this thesis aims to reduce the inefficiency of the recycling process. Data Envelopment Analysis (DEA) of the relationship between inputs and outputs of 33 facilities nationwide, excluding facility data (insufficient) among 394, (238 public, and 156 private ones), as of the end of 2020, which is running a domestic resource recycling project This study was conducted to investigate the important role in the relative management performance of food waste recycling facilities.It was hypothesized that the influence of business history, facility capacity, capital, and machinery of a company running a food waste recycling business on sales was tested.

• Journal of Biosystems Engineering
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• v.35 no.5
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• pp.336-342
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• 2010

This study was performed to develop extrusion pelletizer for pelletizing the compost waste food. The effect of water content on the shape of pellet, the relationship between diameter of pellet and of extrusion hole and the relationship between extrusion force and die angle were investigated. Considering the stable shape of compost pellet and the operation efficiency of pelletizer, the water content of 2~4% was considered as the best condition. And the compost pellet could not maintain it's shape at the water content of 10% or over. The strongest extrusion force was needs when the die angle had $90^{\circ}C$ in 6 mm extrusion hole diameter, on the other hand, the weakest extrusion force was need at the die angle of $45^{\circ}{\sim}65^{\circ}$. The compression strength of pellet shows the highest strength of 9.2Mpa when we make the compost pellet after screening the compost and make it with a size of 1.18 mm(No.16) or less.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.623-631
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• 2000

Advanced Life Support Systems (ALSS) are being studied to support human life during long-duration space missions. ALSS can be categorized into four subsystems: Crew, Biomass Production, Food Processing and Nutrition, Waste Processing and Resource Recovery. The System Studies and Modeling (SSM) team of New Jersey-NASA Specialized Center of Research and Training (NJ-NSCORT) has facilitated and conducted analyses of ALSS to address systems level issues. The underlying concept of the SSM work is to enable the effective utilization of information to aid in planning, analysis, design, management, and operation of ALSS and their components. Analytical tools and computer models for ALSS analyses have been developed and implemented for value-added information processing. The results of analyses have been delivered through the Internet for effective communication within the advanced life support (ALS) community. Several modeling paradigms have been explored by developing tools for use in systems analysis. They include object-oriented approach for top-level models, procedural approach for process-level models, and application of commercially available modeling tools such as MATLAB$\^$(R)//Simulink$\^$(R)/. Every paradigm has its particular applicability for the purpose of modeling work. An overview is presented of the systems studies and modeling work conducted by the NJ-NSCORT SSM team in its efforts to provide systems analysis capabilities to the ALS community. The experience gained and the analytical tools developed from this work can be extended to solving problems encountered in general agriculture.

• Agricultural and Biosystems Engineering
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• v.2 no.2
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• pp.41-49
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• 2001

Advanced Life Support Systems(ALSS) are being studied to support human life during long-duration space missions. ALSS can be categorized into four subsystems: Crew, Biomass Production, Food Processing and Nutrition, Waste Processing and Resource Recovery. The System Studies and Modeling (SSM) team of New Jersey-NASA Specialized Center of Research and Training (NJ-NSCORT) has facilitated and conducted analyses of ALSS to address systems level issues. The underlying concept of the SSM work is to enable the effective utilization of information to aid in planning, analysis, design, management, and operation of ALSS and their components. Analytical tools and computer models for ALSS analyses have been developed and implemented for value-added information processing. The results of analyses heave been delivered through the internet for effective communication within the advanced life support (ALS) community. Several modeling paradigms have been explored by developing tools for use in systems analysis. they include objected-oriented approach for top-level models, procedureal approach for process-level models, and application of commercially available modeling tools such as $MATLAB^{R}$/$Simulink^{R}$. Every paradigm has its particular applicability for the purpose of modeling work. an overview is presented of the systems studies and modeling work conducted by the NJ-NSCORT SSM team in its efforts to provide systems analysis capabilities to the ALS community. The experience gained and the analytical tools developed from this work can be extended to solving problems encountered in general agriculture.