• Title/Summary/Keyword: life-time use

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The Study of Preparation of Block Using Wastewater Sludge of Petrochemical Factory (석유화학공장 폐수슬러지를 이용한 벽돌제조 연구)

  • Hu, Kwan;Lu, Juk-Yong;Wang, Seung-Ho
    • Journal of the Korea Organic Resources Recycling Association
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    • v.11 no.2
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    • pp.66-73
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    • 2003
  • To investigate the availability of solidified wastes as resource, wastewater sludge, waste gypsum and fly ash were mixed and the results with various mixing ratios are as follows. Compressive strength turned out to be increasing as the amount of waste gypsum increases, keeps longer curing inhibition, and higher forming Pressure under the conditions of waste gypsum/sludge ratio 0.31-0.45, and 0.9kg cement as 15% and 1.2kg cement as 20% of total amount. Solidified agent under the fly ash/sludge ratio 0.45, 0.6, compressive strength seemed to be higher than standard one which means solidified wastes with these conditions could be applicable in real life. These results inform that concentrations of the leachate $Cr^{+6}$, Cu, Zn, Cd, Pb solidified matrix, containing low concentration of heavy metal, were cured with/without enough time it still will cause adverse effect on nature environment and application of heavy metal sequester must be needed to reuse industrial wastes from incineration plant solidified matrix. Total cost price, when considering manufacturing capability of the facilities for resourcerizing as 18,000ton was presented 678,664,000 won, as it were, manufacturing cost price was 37,704 won per ton. The results as above has shown that it's possible to use the mixture of waste gypsum/sludge, fly ash/sludge, cement, additions, and solidification matter as substitute of materials like brick, block, interlocking which has proper compressive strength of KS L 5201 and KS F 4004.

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Analysis of the Effect of Temperature on the Pesticide Efficacy and Simulation of the Change in the Amount of Pesticide Use (온도가 농약효과에 미치는 영향분석 및 농약사용량 예측 모의실험)

  • Mo, Hyoung-ho;Kang, Ju Wan;Cho, Kijong;Bae, Yeon Jae;Lee, Mi-Gyung;Park, Jung-Joon
    • Korean Journal of Environmental Biology
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    • v.34 no.1
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    • pp.56-62
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    • 2016
  • Pest population density models are very important to monitor the initial occurrence and to understand the continuous fluctuation pattern of pest in pest management. This is one of the major issues in agriculture because these predictions make pesticides more effective and environmental impact of pesticides less. In this study, we combined and predicted the mortality change of pest caused by pesticides with temperature change and population dynamic model. Sensitive strain of two-spotted spider mite (Tetranychus urticae Koch) with kidney bean leaf as host was exposed to mixed acaricide, Acrinathrin-Spiromesifen and organotin acaricide, Azocyclotin, at 20, 25, 30, and $35^{\circ}C$, respectively. There was significant difference in mortality of T. urticae among pesticides and temperatures. We used DYMEX to simulate population density of T. urticae and predicted that the initial management time and number of chemical control would be changed in the future with climate change. There would be implications for strategies for pest management and selection process of pesticide in the future corresponding climate change.

A study on the Shelf-life Extension of Minimally Processed Carrot (최소가공 당근의 유통기한 연장 연구)

  • Lee, Kyoung-Hae;Lim, Hui-Kyoung
    • Journal of Food Hygiene and Safety
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    • v.23 no.4
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    • pp.330-337
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    • 2008
  • Betarich carrots were washed at various hypochloric acid(HCA) concentration and steeping time and packed in PE bag keeping at $8^{\circ}C$ for 12 days, in order eventually to examine microbiology, firmness, surface color, whiteness index(WI) and sensory quality. It was found that total bacterial counts at T-II and T-III with the 3 minute steeping were $4.37{\pm}0.19\;\log\;CFU/g$ and $4.27{\pm}0.13\;\log\;CFU/g$ respectively, showing slight decrease compared to control condition. E. coli was not detected at all treatments but less coliforms were detected at the 8-day treatments of T-II and T-III. Treatment of 3-minute steeping showed smaller reduction in firmness than that of I-minute steeping at 12-days, and T-1 (T-3) had the largest (smallest) reduction among them. It was also found that during the treatment the L-value showed decreasing trend, but the parameter a- and b-value showed increasing trend. WI increased, and its change was small with the increase in HCA concentration. The sensory quality check after 8 day storage showed that evaluation of the off-flavor appeared to be significantly high (p<0.05) at both non-treatment and HCA treatment. On the basis of the results above, it is likely to be more effective to prolong the period of circulation of beta rich carrots if you use HCA over 50 ppm for washing betarich carrots. This study will contribute to improve safety and quality in circulation of beta rich carrots.

A Study on the Value Expression of the Multinational Corporation Advertisements advanced into Korea - especially on newspaper advertisements - (국내 진출 다국적기업 광고물의 가치표현연구 - 신문광고를 중심으로 -)

  • 정창준
    • Archives of design research
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    • v.16 no.1
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    • pp.103-116
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    • 2003
  • As the globalization become the main stream in our world, there is no exception also on the cultural section. And we are En the midst of this rapid transition. In the case of advertising market, we opened to those agencies in abroad in the early year of 1990 and now completely opened. On this thesis, the multinational corporation advertising was studied and researched by empirical case study. The main topic is the value expression in the advertising creativity viewed on the cultural level. The multinational corporations that have an eminent, powerful brands produces much of goods wend widely with their powerful brands and extend their marketing activities to abroad. For example, those non-alcoholic beverages, pharmaceutical products, cosmetics, electronic appliances, vehicles, sports shoes, clothes are their main exports, and they broaden the product category, market size to the global market. They also use an expert marketing skill accumulated for a long time. The advertising activities is one of the useful method to extend their global market abroad enhacing continuously brand value. And much of the multinational corporation's advertising are suspected of negative effects that advertisements works on a tool which curies so called uniformed ideology - various ruling ideology - with commercial messages. These advertising affect an developing country's moral value, life style, social value, and others. And they weaken those developing country's unique tradition, culture by putting their own ideology. Those who have a critical position on the advertising activities have been careful in judging it's effects. The result of this study which of the value system is expressed in the multinational corporation's advertisements are; First, the self - esteem value is classified by western value, and it was founded out much more in the domestic corporation's advertisements then multinational ones. Second, the security value system is classified by western value system, and it's outcome was much the same as former one. Consequently, the multinational corporation's advertisements have less of an western value expression relative to korean advertisements. Those outcomes may infer that the multinational corporations prefer to an compromise creative strategy in korea for avoiding cultural conflicts.

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Dissolution Profile Analysis of Hydroxypropyl Methylcellulose-based Vitamin C Tablets (Hydroxypropyl methylcellulose를 활용한 비타민 C 지속성 정제의 용출 특성 분석)

  • Cha, Ja-Hyun;Hong, Jun-Kee;Lee, Sung-Wan;Cha, Jae-Uk;Ko, Won-Hwa;Baek, Hyon-Ho;Park, Hyun-Jin
    • Korean Journal of Food Science and Technology
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    • v.44 no.3
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    • pp.274-279
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    • 2012
  • The objective of this study was to develop oral matrix tablets for the sustained release of vitamin C. In this study hydroxypropyl methylcellulose (HPMC) has been utilized as an excipient, as it is one of the most widely used polymers, for use during long periods of time in formations. The vitamin C tablet formulation depends on the molecular weight and concentration of sustained-delivery in HPMC. Anti-oxidants have been added as a dissolution medium in order to prevent vitamin C degradation in water. The dissolution test was carried out in a distilled water medium, and the release model equation was applied to analyze the vitamin C release pattern. The results demonstrated that the release and lasting power of vitamin C tablets, containing HPMC, lasted for more than 12 h.

Measurement of Classes Complexity in the Object-Oriented Analysis Phase (객체지향 분석 단계에서의 클래스 복잡도 측정)

  • Kim, Yu-Kyung;Park, Jai-Nyun
    • Journal of KIISE:Software and Applications
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    • v.28 no.10
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    • pp.720-731
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    • 2001
  • Complexity metrics have been developed for the structured paradigm of software development are not suitable for use with the object-oriented(OO) paradigm, because they do not support key object-oriented concepts such as inheritance, polymorphism. message passing and encapsulation. There are many researches on OO software metrics such as program complexity or design metrics. But metrics measuring the complexity of classes at the OO analysis phase are needed because they provide earlier feedback to the development project. and earlier feedback means more effective developing and less costly maintenance. In this paper, we propose the new metrics to measure the complexity of analysis classes which draw out in the analysis based on RUP(Rational Unified Process). By the collaboration complexity, is denoted by CC, we mean the maximum number of the collaborations can be achieved with each of the collaborator and determine the potential complexity. And the interface complexity, is denoted by IC, shows the difficulty related to understand the interface of collaborators each other. We verify theoretically the suggested metrics for Weyuker's nine properties. Moreover, we show the computation results for analysis classes of the system which automatically respond to questions of the user using the text mining technique. As a result of the comparison of CC and CBO and WMC suggested by Chidamber and Kemerer, the class that have highly the proposed metric value maintain the high complexity at the design phase too. And the complexity can be represented by CC and IC more than CBO and WMC. We can expect that our metrics may provide us the earlier feedback and hence possible to predict the efforts, costs and time required to remainder processes. As a result, we expect to develop the cost-effective OO software by reviewing the complexity of analysis classes in the first stage of SDLC(Software Development Life Cycle).

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Implementation of a File System for Flash Memory (플래시 메모리를 위한 파일 시스템의 구현)

  • Park, Sang-Ho;Ahn, Woo-Hyun;Park, Dae-Yeon;Kim, Jeong-Ki;Park, Sung-Min
    • Journal of KIISE:Computing Practices and Letters
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    • v.7 no.5
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    • pp.402-415
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    • 2001
  • Advantages of flash memories are their shock resistance and fast read speed, which is much faster than that of a HDD. Because of these characteristics, they are increasingly used in the traditional household electric appliance and portable handset and therefore, development of file systems which use them as storage medium is increasingly needed. But they have two problems as storage medium. First, data stored in them cannot be overwritten: it must be erased before new data can be stored. Unfortunately, this erase operation usually takes about one second. Consequently, updating data in flash memories takes long time. In this paper, their problem is solved by using a data update mechanism like LFS(Log-structured File System). Second, their erase operations are restricted. We propose novel cleaning policy in order to increase the life cycle. We implemented FAT file system, which is suitable to small storage medium and solved problems, which usually happen in implementing FAT. We evaluated the performance of sequential writes and random writes on our implemented flash file system.

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Design of a Holter Monitoring System with Flash Memory Card (플레쉬 메모리 카드를 이용한 홀터 심전계의 설계)

  • 송근국;이경중
    • Journal of Biomedical Engineering Research
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    • v.19 no.3
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    • pp.251-260
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    • 1998
  • The Holter monitoring system is a widely used noninvasive diagnostic tool for ambulatory patient who may be at risk from latent life-threatening cardiac abnormalities. In this paper, we design a high performance intelligent holter monitoring system which is characterized by the small-sized and the low-power consumption. The system hardware consists of one-chip microcontroller(68HC11E9), ECG preprocessing circuit, and flash memory card. ECG preprocessing circuit is made of ECG preamplifier with gain of 250, 500 and 1000, the bandpass filter with bandwidth of 0.05-100Hz, the auto-balancing circuit and the saturation-calibrating circuit to eliminate baseline wandering, ECG signal sampled at 240 samples/sec is converted to the digital signal. We use a linear recursive filter and preprocessing algorithm to detect the ECG parameters which are QRS complex, and Q-R-T points, ST-level, HR, QT interval. The long-term acquired ECG signals and diagnostic parameters are compressed by the MFan(Modified Fan) and the delta modulation method. To easily interface with the PC based analyzer program which is operated in DOS and Windows, the compressed data, that are compatible to FFS(flash file system) format, are stored at the flash memory card with SBF(symmetric block format).

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A Study on the Disaster Prevention Technology of the Switchboard with Upper and Lower Bending Type Seismic Pads (상하굴절형 내진패드를 설치한 수배전반 방재기술에 관한 연구)

  • Lee, Taeshik;Seok, Gumcheul;Lee, Jaewon;Kim, Taejin;Kim, Jaekwon;Cho, Woncheol
    • Journal of Korean Society of Disaster and Security
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    • v.10 no.1
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    • pp.85-90
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    • 2017
  • The purpose of this study is to investigate the effect of vertical and horizontal refraction on the lower part of the power supply and control system of various facilities and machinery that use electricity, so that the power distribution system, which is an important electric facility installed in buildings and public facilities, Type earthquake resistant pads to protect the substructure and prevent short-circuiting on the upper part of the system. The GR-63-CORE (Scale 8.3 class) It is earthquake disaster prevention and disaster prevention technology that satisfies seismic performance. As a research result, it is possible to protect the electricity and communication infrastructure, which can contribute to shortening the time for recovering the electric facilities to the normal state in case of an earthquake, and preventing the fire caused by the destruction of the electricity supply facility in case of an earthquake. As a result, it is possible to minimize the spread of fire that occurs when a large-scale earthquake occurs and to minimize the damage of people and damage to property, and it can contribute to the securing of electric infrastructure that enables citizens to quickly recover to daily life even after suffering a major earthquake. In addition, the technology can be applied to ensure the seismic resistance of the equipment in the communication and computer room, and it can be applied to various fields where the facility function can be stopped due to the shaking of the earthquake base.

A Study of Realistic Mathematics Education - Focusing on the learning of algorithms in primary school - (현실적 수학교육에 대한 고찰 - 초등학교의 알고리듬 학습을 중심으로 -)

  • 정영옥
    • Journal of Educational Research in Mathematics
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    • v.9 no.1
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    • pp.81-109
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    • 1999
  • This study aims to reflect the basic principles and teaching-teaming principles of Realistic Mathematics Education in order to suppose an way in which mathematics as an activity is carried out in primary school. The development of what is known as RME started almost thirty years ago. It is founded by Freudenthal and his colleagues at the former IOWO. Freudenthal stressed the idea of matheamatics as a human activity. According to him, the key principles of RME are as follows: guided reinvention and progressive mathematisation, level theory, and didactical phenomenology. This means that children have guided opportunities to reinvent mathematics by doing it and so the focal point should not be on mathematics as a closed system but on the process of mathematisation. There are different levels in learning process. One should let children make the transition from one level to the next level in the progress of mathematisation in realistic contexts. Here, contexts means that domain of reality, which in some particular learning process is disclosed to the learner in order to be mathematised. And the word of 'realistic' is related not just with the real world, but is related to the emphasis that RME puts on offering the students problem situations which they can imagine. Under the background of these principles, RME supposes the following five instruction principles: phenomenological exploration, bridging by vertical instruments, pupils' own constructions and productions, interactivity, and interwining of learning strands. In order to reflect how to realize these principles in practice, the teaming process of algorithms is illustrated. In this process, children follow a learning route that takes its inspiration from the history of mathematics or from their own informal knowledge and strategies. Considering long division, the first levee is associated with real-life activities such as sharing sweets among children. Here, children use their own strategies to solve context problems. The second level is entered when the same sweet problems is presented and a model of the situation is created. Then it is focused on finding shortcomings. Finally, the schema of division becomes a subject of investigation. Comparing realistic mathematics education with constructivistic mathematics education, there interaction, reflective thinking, conflict situation are many similarities but there are alsodifferences. They share the characteristics such as mathematics as a human activity, active learner, etc. But in RME, it is focused on the delicate balance between the spontaneity of children and the authority of teachers, and the development of long-term loaming process which is structured but flexible. In this respect two forms of mathematics education are different. Here, we learn how to develop mathematics curriculum that respects the theory of children on reality and at the same time the theory of mathematics experts. In order to connect the informal mathematics of children and formal mathematics, we need more teachers as researchers and more researchers as observers who try to find the mathematical informal notions of children and anticipate routes of children's learning through thought-experiment continuously.

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