• Journal of KIISE:Computing Practices and Letters
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• v.15 no.12
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• pp.963-967
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• 2009

The Log-structured File System (LFS) collects all modified data into a memory buffer and writes them sequentially to a segment on disk. Therefore, it has the potential to utilize the maximum bandwidth of storage devices where sequential writes are much faster than random writes. However, as disk space is finite, LFS has to conduct cleaning to produce free segments. This cleaning operation is the main reason LFS performance deteriorates when file system utilization is high. To overcome painful cleaning and reduced performance of LFS, we propose the segment space recycling (SSR) scheme that directly writes modified data to invalid areas of the segments and describe the classification method of data and segment to consider locality of reference for optimizing SSR scheme. We implement U-LFS, which employs our segment space recycling scheme in LFS, and experimental results show that SSR scheme increases performance of WOLF by up to 1.9 times in HDD and 1.6 times in SSD when file system utilization is high.

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.1
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• pp.15-23
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• 1997

Commercial inocula and mature compost were added separately to food wastes in order to compare the inoculating effect on garbage decomposition. Among commercial inocula available in the market, GM (Green Microorganisms) and EM (Effective Microorganisms) were selected as test inocula. Garbage decompostion were evaluated in Volatile Solid (VS) reduction and FDA (Fluorescein DiAcetate) hydrolysis activity. VS reduction with mature compost experiment was higher than that with GM-added one. VS reduction rates were about 32% with mature compost and 27% with GM. When food wastes were treated with GM and EM based on the manufacturer's specifications, GM-added and EM-added food wastes showed only 8% and 9% of VS reduction respectively, which are much lower than those with the mature compost. FDA hydrolysis activity increased during the first 10 days of active composting periods for the composting experiments, while it decreased continuously for the experiments based on manufacturer's specifications.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.3
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• pp.86-94
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• 2004

The characteristics of food waste in our country is high contents of water and sodium chloride(NaCl). Average water contents of household garbage was 80.0%, and those of wastes of restaurants and of wholesale market of agricultural products was 76.9% and 90.0%, respectively. The NaCl contents were high in household garbage and restaurant's waste as 3.36% and 4.84%, respectively. The NaCl contents of food waste composts made by various techniques known upto now were under the level of 1% by fresh weight basis. But these techniques has some problem that is environment pollution from treated water and high equipment cost. The application to agricultural land of food waste compost that is not sufficiently removed NaCl was considered to be improper due to salt accumulation in soils and plant growth inhibition by salt stress. The purpose of this study is to decompose NaCl in food waste compost using triple salt and this method is differ from existing chemical method. Also, reaction of NaCl with triple salt produced KCl that is basic material of potassium fertilizer. The experiment results of growing lettuce produced difference between food waste compost and treated food waste compost with triple salt. The latter got more high sprouting ratio and a growth rate.

• Journal of agricultural medicine and community health
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• v.21 no.1
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• pp.97-105
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• 1996

This study conducted to determine the evaluation and improvement for enforcement of the waste recycling system in Pohang city and surveyed 4 areas at the southern and northern districts respectively by a team of two officials during the period 6 February 7 February 1995. The rates of the use for waste recycling system's envelope from home trash were 94.2% at the northern district and 92.8% at the southern district by areas, 95.6% at the group houses (apartments and tenement houses) and 91.3% at the separate houses by patterns of house, the low economic class 96.4%, the middle economic class 96.3% and the upper economic class 87.5% by the economic levels, and the bell method 96.5%, the container method 95.6%, door take method 86.1% in order, respectively. The trash from houses were garbage 57.4%, paper 18.7%, plastic 10.3%, fiber 7.9%, bottle 2.7%, metal and can 1.4%, and wood and rubber 0.7% in order. The rates of the reuse trash(reuse possible paper, plastic, bottle, can and metal) were 20.2% of the total, 21.8% at the southern district and 18.5% at the northern district by areas, 25.7% at the separate houses and 14.7% at the group houses(apartments and tenement houses) by patterns of house, and the door take method 34.3%, the bell take method 17.1% and the container take method 14.7% in order, respectively. There were the double envelopes of the plastic bag from stories 46.3% and the clear plastic bag 29.5% in the waste cycling system's envelopes. There were 1.9 double envelopes in the waste cycling system's envelopes. Garbage occupied more than half of the total trash, so it is need to be compost and provender.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.997-1006
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• 2009

Organic removal efficiency and methane production rate, a feasibility of power generation from biogas, and the optimum conditions for membrane operation were evaluated for the pilot scale (5 tons/day) two-phase anaerobic digestion coupled with ultra filtration (TPADUF) system fed with garbage leachate. The TPADUF system is consisted of a thermophilic acidogenic reactor, a mesophilic methanogenic reactor, and an UF membrane. When garbage leachate with 150 g/L of TCOD was fed to the TPADUF up to organic loading rate (OLR) of 11.1 g COD/L/d, the effluent TCOD was lower than 6 g/L and the average removal efficiencies of TCOD and SCOD were higher than 95%. The methane composition of the gas was 65%, and the methane yield was 39 $m^3/m^3$ garbage leachatefed, 260 $m^3$/tons $COD_{added}$, or 270 $m^3$/tons $COD_{removed}$, even there was some gas leak. The power production per consumed gas was 0.96 kWh/$m^3$ gas or 1.49 kWh/$m^3$ methane. This lower power production efficiency mainly due to the small capacity of gas engine (15 kW class). The membrane was operated at the average flux of 10 L/$m^2$/hr. When the flux decreased, washing with water and chemical (NaOCl) was conducted to restore the flux. In the TPADUF system, optimum pH could be maintained without alkali addition by recycling the membrane concentrate or mixed liquor of the methanogenic digester to the acidogenic reactor. Also, partial production of methane in the acidogenic reactor had a positive effect on lowering the OLR of the methanogenic reactor.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.1
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• pp.23-28
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• 2015

This study was conducted to evaluate the biodegradation characteristics of food waste on various collection systems using anaerobic batch test. The ultimate methane production from food waste in standard plastic garbage bags (sample A) was $285.6mL\;CH_4/g$ volatile solids (VS) which is the lowest, and reaction constant was $0.215d^{-1}$. The ultimate methane production from food waste in waste vessel based on RFID (sample D) was $493.4mL\;CH_4/g$ VS which is the highest, and reaction constant was $0.162d^{-1}$. The determinants of rate limiting step on all samples showed positive numbers, and the methane production step was found a rate limiting step.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.3
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• pp.60-66
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• 2003

The purpose of this study was to investigate the effective pretreatment of foodwaste for the anaerobic digestion. Considering the foodwaste generation and the anaerobic digester for municipal wastewater sludges, the some pretreatment processes were performed such as the grinding of foodwastes with the addition of water, the mixing with sludges, and the hydrolysis with the addition of NaOH. The results were as followings ; 1. As the stage of feasibility test in laboratory scale, the foodwaste grinding using a household garbage disposer was performed with three different water mixing ratios of 1:1, 1:5 and 1:9 as weight base. The physicochemical characteristics of grinded foodwaste were analyzed and the effective conditions was recommended as the 1 :5mixing ratio of foodwaste and water and the below 8mm particle size. 2. And the mixing of foodwaste and municipal wastewater sludge was studied with three different mixing ratios of 1:9, 3:7 and 5:5 as weight base. The physicochemical characteristics of the mixed foodwaste and sludges were analyzed and the effective mixing ratio was recommended as 3:7 of foodwaste and sludge.

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.1
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• pp.43-52
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• 1997

This study was conducted to analysis citizen's attitude and style to the foodwaste from loth Sept. to 30th Sept. in 1996. The research was used questionare method and the analysis was used prequency analysis and cross table method by SPSS (scientific statistics). they answered that the most serious environment problem was waste problem and the best way to settle waste problem was to reduce waste production itself. And they answered that to settle environment problems, it was most important for us to change our life style. But It was not agreed between consciousness and action(execution). Because most of the food-related waste was among household waste, it's settlement was the most importment thing than any other. Nevertheless the seperation of waste was essential to effective incineration, the seperation process was not actually conducted and only a few housewife knew the difference of incinerable and non-incinerable waste. The recycling for the disused dry-cells and garbage is not completly. But we think that if the effective government's recycling counterplan for wastes, foodwaste or wasted dry cell, etc., is estabilished, rates of seperation and collection was increasing. Much usuage of onetime vinyl bag for shopping was become the one of the main cause in increasing the package waste, and so it was needed to use the longlife shopping basket.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.4
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• pp.310-314
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• 2020

Although waste oil derived fuel (WDF) production technology was developed under a government initiative ~10 years ago, it became stagnant owing to the small size of participating companies, residents' rejection of foul odor, and the nature of the technology for recycling waste that was avoided. However, this subject is under the spotlight again because of recent developments, such as garbage crisis. In particular, plastic is the most difficult waste to dispose of, with more than 4 million tons of plastic waste produced every year according to statistics from the Ministry of Environment. The most effective method for treating plastic waste is to produce WDF through low temperature thermal decomposition. The WDF includes several volatile ingredients that mostly limit the use of fuel for boilers, owing to safety concerns. In particular, flash point is legally stipulated because of secondary contamination in the distribution process and the risk of fire and explosion. It is required that external shipments (distribution) should be maintained in the range of at least 30~60℃ (excluding explosion prevention facilities) for diesel power generation. Therefore, this study seeks to find the flash point that is best suited to WDFs produced from plastic waste.

• The Korean Journal of Physiology and Pharmacology
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• v.27 no.4
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• pp.311-323
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• 2023

Ion homeostasis, which is regulated by ion channels, is crucial for intracellular signaling. These channels are involved in diverse signaling pathways, including cell proliferation, migration, and intracellular calcium dynamics. Consequently, ion channel dysfunction can lead to various diseases. In addition, these channels are present in the plasma membrane and intracellular organelles. However, our understanding of the function of intracellular organellar ion channels is limited. Recent advancements in electrophysiological techniques have enabled us to record ion channels within intracellular organelles and thus learn more about their functions. Autophagy is a vital process of intracellular protein degradation that facilitates the breakdown of aged, unnecessary, and harmful proteins into their amino acid residues. Lysosomes, which were previously considered protein-degrading garbage boxes, are now recognized as crucial intracellular sensors that play significant roles in normal signaling and disease pathogenesis. Lysosomes participate in various processes, including digestion, recycling, exocytosis, calcium signaling, nutrient sensing, and wound repair, highlighting the importance of ion channels in these signaling pathways. This review focuses on different lysosomal ion channels, including those associated with diseases, and provides insights into their cellular functions. By summarizing the existing knowledge and literature, this review emphasizes the need for further research in this field. Ultimately, this study aims to provide novel perspectives on the regulation of lysosomal ion channels and the significance of ion-associated signaling in intracellular functions to develop innovative therapeutic targets for rare and lysosomal storage diseases.