• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.225-229
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• 2001

There are about 41% (by weight) of scrap tires were pulverized to produce rubber powder and granules in the tire recycling industry of Taiwan. However, the reuse of the by-products, steel and fiber, of the scrap tires still needs to be improved. It is difficult to remove the remaining rubber on the surface of steel or fiber. This problem reduce the availability for further reuse of steel and fiber. In addition to the improvement of magnetic, gravity separation techniques or carbonization process, using cryogenic shredding process to separate rubber and fiber (or steel) had been used as another alternative. Cryogenic shredding process for scrap tires showed many advantages, the objective of this paper is to explore the mechanisms for the cryogenic shredding process of scrap tires. Cryo-SEM is used to investigate the topographic information, in-situ, from room temperature to -195$^{\circ}C$ . One square inch shredded tire chips are prepared for SEM study. The percentage of the shrinkage of rubber is also estimated, ca. 6.7%. Mechanisms of cryogenic shredding effects on the tire chips are discussed. The proper practice of cryogenic shredding process far scrap tires is also suggested.

• Journal of Korea Multimedia Society
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• v.10 no.12
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• pp.1539-1550
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• 2007

As XML is increasingly used for representing and exchanging data, relational database systems have been trying extend their features to handle XML documents XML documents can be stored in a column with XML data type like primitive types. The shredding method, which is one of the traditional methods for storing and managing XML documents in RDBMS, is still useful and viable although it has some drawbacks due to the structural discrepancy between XML and relational databases. This method may be suitable for data-centric XML documents with simple schema. This paper presents the extended version of the Association inlining method that is based on inlined shredding and compares the performance of querying processing to that of XML type method of conventional relational database systems. The experiments showed that in most cases our method resulted in better performance than the other method based on XML data type. This is due to the fact that our shredding method keeps and uses the order and path information of XML documents. The path table has the information of the corresponding table and column for each distinct path and the structure information of the XML document is extracted and stored in data tables.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.1031-1040
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• 1996

Spawn bottle cutting and spawn cake shredding machine has been developed to save the farm labor and operating cost for mushroom growing farmers. The prototype can cut the bottom and side of the bottle while shredding the spawn cake by one farmer. The cutting plastic shell is done by two couples of high speed disc saws that can cut cross section and lengthwise two side of the bottle, while spawn cake shredding is done by spike teethed rotating drum and wiremesh concave. The optimum speed of cutting disc saw was observed 1.700rpm both the cross cutting saw and lengthwise cutting saw in consideration of the cutting accuracy. And the location for the instalation of cross cutting disc saw was considered as around 4 mm above the table bottom , while the optimum clearance between two edges of lengthwise cutting disc saw was showed 86mm. For the sawdust spawn cake shredder , proper size of spawn sawdust granule was observed in the 15 x 15mm size withmesh concave with the shredding rum speed of 500rpm. The prototype can be reduce 73 per cent of working hours with the working cost reduction of 49 per cent compare with those of conventional operation.

• Journal of Biosystems Engineering
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• v.34 no.6
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• pp.411-419
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• 2009

This study was carried out to develop a shredding-burying machine for application of gramineae green manure crops that were tall and had high biomass yield such as sudan grass and rye. We made a prototype to operate both shredding and burying concurrently to attach at middle-sized tractors. Field tests were performed with the prototype to treat rye and sudan grass. The test results showed that the average cutting length became shorter and the quantity of entwined stem became obviously decreased when the PTO shaft speed was fast and running speed was slow. Also, We found, when the cut stem length became shorter, the burying ratio became more increasing and the PTO power requirement became more decreasing. Working efficiency of the prototype was better than conventional Rotary. The test results for treating rye/sudan grass with prototype showed that average cutting length was 21.2/22.5 cm and burying ratio was 98.4/98.1% when the PTO shaft speed was 1,000/1,000 rpm and running speed was 0.25/0.17 m/s. Also, the working performance of the prototype was 0.79 and 1.14 h/10 a for rye and sudan grass, respectively. Finally, we found that the prototype of shredding-burying machine was better for labor than conventional method that required at least 3 times bigger tractor.

• Resources Recycling
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• v.11 no.4
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• pp.11-16
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• 2002

Analysis and separation of constituent materials of old car have been performed by using the industrial shredding line. For this aim, three old cars made by domestic automobile manufacturers, Sonata II, Sephia and Prince were chosen and delivered in pressed form without engine, tires and doors, etc. Shredding line was substantially composed of pre- and main-shredder. cyclone, magnetic separation, eddy current separation and man-power separation. From the separation of shredder products, iron scrap was observed to be the major material of old car accounting for 60.1 ％ of total weight and non-ferrous metals involving Al, Cu and Zn, etc. were about 2％. Light fluff, about 90％ of total fluff product, was comprised with plastic, fiber and sponge, etc. and the fraction of 5 cm undersize in light fluff was 70.5%. In case of heavy fluff, however. rubber and plastic were found to be the major constituent materials of it. Among the constituent materials of fluff, plastic showed the highest calorific value, more than 10,000 cal/gr and leather and rubber showed relatively high chlorine content, 10.3 and 2.55 wt%, respectively.

• Toxicological Research
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• v.30 no.4
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• pp.267-276
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• 2014

Exposures to lead (Pb) are associated with neurological problems including psychiatric disorders and impaired learning and memory. Pb can be absorbed by iron transporters, which are up-regulated in hereditary hemochromatosis, an iron overload disorder in which increased iron deposition in various parenchymal organs promote metal-induced oxidative damage. While dysfunction in HFE (High Fe) gene is the major cause of hemochromatosis, the transport and toxicity of Pb in Hfe-related hemochromatosis are largely unknown. To elucidate the relationship between HFE gene dysfunction and Pb absorption, H67D knock-in Hfe-mutant and wild-type mice were given drinking water containing Pb 1.6 mg/ml ad libitum for 6 weeks and examined for behavioral phenotypes using the nestlet-shredding and marble-burying tests. Latency to nestlet-shredding in Pb-treated wild-type mice was prolonged compared with non-exposed wild-types (p < 0.001), whereas Pb exposure did not alter shredding latency in Hfe-mutant mice. In the marble-burying test, Hfe-mutant mice showed an increased number of marbles buried compared with wild-type mice (p = 0.002), indicating more repetitive behavior upon Hfe mutation. Importantly, Pb-exposed wild-type mice buried more marbles than non-exposed wild-types, whereas the number of marbles buried by Hfe-mutant mice did not change whether or not exposed to Pb. These results suggest that Hfe mutation could normalize Pb-induced behavioral alteration. To explore the mechanism of repetitive behavior caused by Pb, western blot analysis was conducted for proteins involved in brain dopamine metabolism. The levels of tyrosine hydroxylase and dopamine transporter increased upon Pb exposure in both genotypes, whereas Hfe-mutant mice displayed down-regulation of the dopamine transporter and dopamine D1 receptor with D2 receptor elevated. Taken together, our data support the idea that both Pb exposure and Hfe mutation increase repetitive behavior in mice and further suggest that these behavioral changes could be associated with altered dopaminergic neurotransmission, providing a therapeutic basis for psychiatric disorders caused by Pb toxicity.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.122-127
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• 2004

The purpose of this study is to introduce the standard of the durability and evaluation method for paper shredder. The major evaluation criteria include shredding capability, shredding blade (or cutter) hardness and edge roughness, and durability. Due to the difficulties in assessing the durability directly, performance deterioration of the shredder was assessed by measuring the torque variation along with the variation in shredded chip size and load, thereby proposing the indirect method of assessing the paper shredder durability.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.293-293
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• 2002

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.230-235
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• 2001

There are more than 15 millions cars or motors in Taiwan. According to the statistics from Environmental Protection Administration, the number of resulting scrap tires are near 110 thousand tons each year. The tire recycle programs in Taiwan were first conducted in 1989 and executed by ROC Scrap Tire Foundation. However, the current efficiency of the tire recycling industry still needs to be improved to minimize the environmental problem or fire hazards caused by scrap tires storage. Ten major tire-recycling factories are surveyed in this study. The investigations include the source of scrap tire, the shredding process, the market of products, the management of wastes disposal, and the difficulties of these sectors. As the varieties of the shredding machines of the recycle factories, there are three kinds of final products which include powder, granular, and chips. The wastes, wires and fibers, produced by the shredding process are the major problems fur all the factories. The percentage of the wire and fiber removal from rubbers still needs to be increased. The best approaches found in this study to increase the efficiency of scrap tire recycling processes are proposed which include the improvement of magnetic separation system fiber/rubber separation system and the minimization of waste disposal. A categorized standard of the processing outputs is suggested as a reference for the decision-making of the tire-recycling factories.

• Journal of Energy Engineering
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• v.29 no.3
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• pp.34-41
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• 2020

Used disposable diapers have been considered for a long time as a type of waste difficult to recycle and valorize due to their composite nature including plastic, cellulose pulp, a super absorbent polymer and either urine, feces or both. Therefore, the fate of disposed diapers often is either incineration or landfill burial which both have various adverse environmental impacts. However, used disposable diapers contain nutrients: cellulose is an organic matter while urine and feces contain non negligible amounts of nitrogen, phosphorus and potassium which are primary nutrients included in most chemical fertilizers used in agriculture. In a scope of waste recycling and valorization, this study focuses on developing a method to achieve nutrient solution extraction from used disposable diapers. The experiment essentially consists in shredding the diapers and letting them macerate in solutions of sodium hydroxide with various concentrations to allow breaking down of the cellulose and super absorbent polymer and release of urine and feces before sterilizing the solutions in an autoclave to remove potential coliform bacteria. At the end of the experiment, a set of parameters is measured for the final solution to identify concentrations of nutrients as well as presence or absence of harmful substances. Results are discussed and directions for future studies are suggested, which include mechanization of the diapers shredding process or added aeration to enhance nitrification and absorption of extracted nutrients from plants.