• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.337-341
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• 2001

A new method to extract gold from pyrite roster cinder, which combines ultra-fine-grinding with resin-in-pulp, has been studied in this paper. Compared with traditional leaching technology, it can short leaching time, avoid complex filter process, lower sodium cyanide consumption and increase gold recovery by 35%. During leaching, aluminium oxide ball was used as stirred medium, hydrogen peroxide as leaching aid and sodium hexametaphosphate as grinding aid. With the high efficiency and chemistry effect of ultra-fine-grinding, the leaching process was developed and the gold leaching rate may reach 88%. With AM-2 Б resin as abosorber and sulfocarbamide (TU) as eluent, gold was recovered from cyanide pulp by resin-in-pulp. AM-2 Б resin has good adsorbability in cyanide solution(pH=10). It was easy to elude gold from the loaded resin with 0.1㏖/L cholhydric acid and 1㏖/L sulfocabamide. The effect of contact time, temperature and acidity etc. on the gold absorption had been examined with static methods. The results showed that the adsorption and desorption of gold could both reach over 98%. The effects of flow rate of solution on dynamic adsorption and elution of gold had been examined with dynamic methods. Breakthrough curve and elution curve had been drawn in this paper. A mild condition was determined through a number of experiments: leaching time 2 hours, liquid solid ratio 4:1, sodium cyanide 3kg/t, hydrogen peroxide 0.05%, sodium hexametaphosphate 0.05%; adsorption time 30 minutes, temperature 10-3$0^{\circ}C$, resin($m\ell$) solid(g) ratio 1:10, eluent resin ratio 10-20:1, velocity of eluent $1.5m\ell$/min. Under the mild condition, the gold recovery may reach 85%.

• 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 the Institute of Electronics Engineers of Korea SP
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• v.40 no.6
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• pp.41-50
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• 2003

For copyright protection of digital contents, we employ watermarking techniques to embed watermark signals into digital host data. In this paper we propose an adaptive watermarking algorithm for three-dimensional (3-D) mesh models. Watermark signals are inserted into vertex coordinates adaptively according to changes of their position values. While we embed strong watermarks in the areas of large variations, watermarks are weakly inserted in other areas. After we generate triangle strips by traversing the 3-D model and convert the Cartesian coordinates to the spherical coordinate system, we calculate variations of vertex positions along the traversed strips. Then, we insert watermark signals into the vertex coordinates adaptively according to the calculated variations. We demonstrate that imperceptibility of the inserted watermark is significantly improved and show the bit error rate (BER) for robustness.

• Journal of the Korean Dietetic Association
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• v.7 no.3
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• pp.282-294
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• 2001

n accordance with the National Health Promotion Act of 1995, newly designed National Health and Nutrition Survey was carried out in winter of 1998. Although this survey amended most of the problems noted in previous Nutrition Surveys, it still had a limitation in reflecting seasonal variation in food intake due to the survey period which was confined to November and December. In order to counterbalance this limitation and estimate the yearly food intake of Korean population, three seasonal nutrition surveys were taken place in spring, summer, and fall of 1999. Seasonal Nutritional survey targeted 15 households each in 60 nationwide primary sampling units(PSUS) which were part of 200 PSUS of 1998 National Health and Nutrition Survey. Therefore, total of 2,700 households were surveyed in 3 seasons. The interviewers visited each household members and carried out face to face interview on household. Daily food intake was monitored using 24 hour recall method. According to the survey results, fruits, beverage and alcohol intake showed large variation with season while processed foods showed almost no variation. And intake of vegetables and fruits were influenced by their own harvesting time and had impact on the list of foods consumed most. With the result of the 1998 NHNS, this study made it possible to estimate the yearly average food intake of Korean population. The result of this survey is expected to be used in planning food supply and setting tolerance level of contaminants of each foods at the government level.

• Journal of Internet Computing and Services
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• v.5 no.3
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• pp.73-86
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• 2004

This paper presents a hybrid digital watermarking scheme for color images, We insert two watermarks in the DWT domain using spread-spectrum correlation-based watermarking in luminance component of the color image and in spatial domain using pixel-value substitution of blue channel of color image. The objectives of this paper are to have the watermark robust to common signal processing and to detect any changes on the watermarked image for tamper detection at the same time. This watermark scheme will have the robustness characteristic as typical in frequency domain watermark, and also ability to detect any changes on the image (tamper detection).

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.6
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• pp.73-91
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• 2014

Recently the countries breeding bears such as China and Vietnam are promoting a policy that gives relief to wild animals through agreement with AAF and WSPA. Currently our country has lacking breeding space for the increased number of bred bears due to the prohibition of bear import and export from joining the CITES in 1992. There needs to be a place that treats, protects accepts breed bears in the terms of animal welfare. The bear park was hoped to be designed as a means to give relief to bears and promote harmony with the local society, and is made of parking area, waiting area, visitors center, treatment research management facilities, restaurants, food warehouse, food store, bear museum, sanitation facilities, gondola, plaza, rehabilitation area for wild animals, outdoor exhibition center, direct indirect experience area of wild animals, resting facilities and areas, photo zones, bear playground, bear experiencing facilities, fences, information facilities, tree protection facilities and more. The design can be used as a reference in examining alternative measures following the future change in breeding policy as a bear park example which reflected the ecology of a bear in the term of animal welfare.

• International Journal of Highway Engineering
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• v.19 no.5
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• pp.163-171
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• 2017

PURPOSES : Traffic safety facilities are used to prevent traffic accidents before they occur by providing drivers with information on traffic situations and the geometric design of roads. However, some facilities not defined in guidelines do not meet installation criteria, yet are being installed and used in order to increase efficiency in traffic flow and prevent traffic accidents in a specific expressway zone. In this study, we have evaluated the effect of delineation system which are not defined in the guideline criteria. METHODS : Different virtual scenarios were created for roads using expressway median barrier chevron signs, with a driving simulator used to evaluate the installation and operational effect of such signs. Ten experiments were performed with left- and right-curved roads at curve radius intervals of 500 m, from 500 m to 2,500 m. RESULTS : For sections with a curve radius of more than 1,500 m, drivers had a clear tendency toward stable driving regardless of delineation system. When a chevron sign is installed on a protection fence in the road curving left, an expanded installation is recommended up to the section with a curve radius of 1,000 m. According to the analysis results for the RHB (Relative High Beta spectrum), driving concentration also improved up to a curve radius of 1,000 m. CONCLUSIONS :The experiment result indicates the extent of biasing within a lane and the manipulation amount of steering handle, were analyzed and found to be affected by curve radius and road alignment regardless of delineation system.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.1
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• pp.117-126
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• 1994

Some of the important and vital roles performed by the Health Care Center of Pohang Iron & Steel Co., Ltd.(POSCO) are the periodic monitoring of the work sites as well as regular medical check-ups for each workers to ensure both pleasant and safe working conditions and to protect employees' health. Pohang Steel Works, which has 42 plants, 26 facilities and 12,000 employees, has an annual crude steel production capacity of 9,670,000 using 24,500,000 ton of raw materials. We have measured lots of areal and personal working environment according to Occupational Safety and Health Law semiannually. All data collected on industrial hygiene is stored and managed by personal computer. The developed of a computerized industrial hygiene control system linked to the company's main computer system will provide efficient evaluation of the working environment as well as critical informations on employees' health. Development of this system had begun in May, 1992 and was completed in March, 1994. The computerized industrial hygiene control system can; 1. store industrial hygiene data, providing key pertinent to the diagnosis of occupational related illnesses, and if necessary, the basis for improving the working environment, 2. decide type and time of medical examination of each work for exposure to specific agents, and supply proper protection periodically, 3. prevent occupational related illnesses through evaluation of environmental and biological monitoring, and performance of epidemiological surveillance, 4. facilitate proper job placement through linking of industrial hygiene control and personnel information systems, 5. monitor job processes. levels of chemical agents used, and new agents introduced, 6. and increase productivity by saving time resulting from the implementation of the computerized sysyte,

• The Korean Society of Law and Medicine
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• v.14 no.2
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• pp.143-172
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• 2013

In order to achieve the purpose of treatment for patients by a doctor, the instruction explanation obligation, which means that he should give patients the description in more details to prepare for postoperative sequelae or complications, is common with the advice explanation obligation as a doctor should ex-plain some information to patients. Since the advice explanation obligation is the benefit and protection of the law for self determination right, but the instruction explanation obligation is one for the integrity of body and life, one can be distinct from the other. Judgments giving the instruction on the concept of instruction explanation obligation, specific methods of implementation and a range of compensation for damage are recently being made by courts at all levels including the Supreme Court. It is the time to systematize them. The contents which have been mainly discussed so far include the essence of above mentioned instruction explanation obligation. However, when the tendency of practice is considered, the efforts are required to admit the organic relevance between instruction explanation obligation and advice explanation obligation and to explain the relationship without any contradiction. For whereabouts of li-ability of proof, patients theoretically demonstrate the failure to implement it. However, when the theoretical consistency is maintained, it is likely to fail the intent to recognize the instruction explanation obligation and it may ask patients to prove something impossible to be proven. Thus, these things should be considered. Moreover, as the instruction explanation obligation is associated with medicine instruction obligation of a pharmacist and the coverage is being extended, it is the time to require the systematic study on the theoretical limit.

• Fire Science and Engineering
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• v.25 no.3
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• pp.72-77
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• 2011

This study aims to provide fundamental information required to establish an efficient maintenance and management system for fire fighting clothing which takes into account the domestic fire protection environment and situation. There aren't any detailed regulations and appropriate pre-inspection systems which would be required for proper maintenance of fire fighting clothing, as well as any test methods to determine the life spans of fire fighting clothing properly. Thus, this study tries to analyze the problems in use of fire fighting clothing and its maintenance situation and summarize overseas maintenance situation for fire fighting clothing. As a result, it is found that domestic fire fighting clothing is washed, repaired, and stored without any systematic management regulations. It is also found that the life spans of fire fighting clothing are determined, based on part of overseas management regulations on fire fighting clothing. Therefore, it is imperative to set up efficient management regulations and test methods for fire fighting clothing which would be required for efficient use of the fire fighting budgets and the life safety of fire fighters.