• Title/Summary/Keyword: Disadvantages

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Simultaneous Removal of NO and SO2 using Microbubble and Reducing Agent (마이크로버블과 환원제를 이용한 습식 NO 및 SO2의 동시제거)

  • Song, Dong Hun;Kang, Jo Hong;Park, Hyun Sic;Song, Hojun;Chung, Yongchul G.
    • Clean Technology
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    • v.27 no.4
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    • pp.341-349
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    • 2021
  • In combustion facilities, the nitrogen and sulfur in fossil fuels react with oxygen to generate air pollutants such as nitrogen oxides (NOX) and sulfur oxides (SOX), which are harmful to the human body and cause environmental pollution. There are regulations worldwide to reduce NOX and SOX, and various technologies are being applied to meet these regulations. There are commercialized methods to reduce NOX and SOX emissions such as selective catalytic reduction (SCR), selective non-catalytic reduction (SNCR) and wet flue gas desulfurization (WFGD), but due to the disadvantages of these methods, many studies have been conducted to simultaneously remove NOX and SOX. However, even in the NOX and SOX simultaneous removal methods, there are problems with wastewater generation due to oxidants and absorbents, costs incurred due to the use of catalysts and electrolysis to activate specific oxidants, and the harmfulness of gas oxidants themselves. Therefore, in this research, microbubbles generated in a high-pressure disperser and reducing agents were used to reduce costs and facilitate wastewater treatment in order to compensate for the shortcomings of the NOX, SOX simultaneous treatment method. It was confirmed through image processing and ESR (electron spin resonance) analysis that the disperser generates real microbubbles. NOX and SOX removal tests according to temperature were also conducted using only microbubbles. In addition, the removal efficiencies of NOX and SOX are about 75% and 99% using a reducing agent and microbubbles to reduce wastewater. When a small amount of oxidizing agent was added to this microbubble system, both NOX and SOX removal rates achieved 99% or more. Based on these findings, it is expected that this suggested method will contribute to solving the cost and environmental problems associated with the wet oxidation removal method.

A Study on the Establishment Case of Technical Standard for Electronic Record Information Package (전자문서 정보패키지 구축 사례 연구 - '공인전자문서보관소 전자문서 정보패키지 기술규격 개발 연구'를 중심으로-)

  • Kim, Sung-Kyum
    • The Korean Journal of Archival Studies
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    • no.16
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    • pp.97-146
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    • 2007
  • Those days when people used paper to make up and manage all kinds of documents in the process of their jobs are gone now. Today electronic types of documents have replaced paper. Unlike paper documents, electronic ones contribute to the maximum job efficiency with their convenience in production and storage. But they too have some disadvantages; it's difficult to distinguish originals and copies like paper documents; it's not easy to examine if there is a change or damage to the documents; they are also prone to alteration and damage by the external influences in the electronic environment; and electronic documents require enormous amounts of workforce and costs for immediate measures to be taken according to the changes to the S/W and H/W environment. Despite all those weaknesses, however, electronic documents increasingly account for more percentage in the current job environment thanks to their job convenience and efficiency of production costs. Both the government and private sector have made efforts to come up with plans to maximize their advantages and minimize their risks at the same time. One of the methods is the Authorized Retention Center which is described in the study. There are a couple of prerequisites for its smooth operation; they should guarantee the legal validity of electronic documents in the administrative aspects and first secure the reliability and authenticity of electronic documents in the technological aspects. Responding to those needs, the Ministry of Commerce, Industry and Energy and the Korea Institute for Electronic Commerce, which were the two main bodies to drive the Authorized Retention Center project, revised the Electronic Commerce Act and supplemented the provisions to guarantee the legal validity of electronic documents in 2005 and conducted researches on the ways to preserve electronic documents for a long term and secure their reliability, which had been demanded by the users of the center, in 2006. In an attempt to fulfill those goals of the Authorized Retention Center, this study researched technical standard for electronic record information package of the center and applied the ISO 14721 information package model that's the standard for the long-term preservation of digital data. It also suggested a process to produce and manage information package so that there would be the SIP, AIP and DIP metadata features for the production, preservation, and utilization by users points of electronic documents and they could be implemented according to the center's policies. Based on the previous study, the study introduced the flow charts among the production and progress process, application methods and packages of technical standard for electronic record information package at the center and suggested some issues that should be consistently researched in the field of records management based on the results.

A Study on the Verification of an Indoor Test of a Portable Penetration Meter Using the Cone Penetration Test Method (자유낙하 콘관입시험법을 활용한 휴대용 다짐도 측정기의 실내시험을 통한 검증 연구)

  • Park, Geoun Hyun;Yang, An Seung
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.2
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    • pp.41-48
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    • 2019
  • Soil compaction is one of the most important activities in the area of civil works, including road construction, airport construction, port construction and backfilling construction of structures. Soil compaction, particularly in road construction, can be categorized into subgrade compaction and roadbed compaction, and is significant work that when done poorly can serve as a factor causing poor construction due to a lack of compaction. Currently, there are many different types of compaction tests, and the plate bearing test and the unit weight of soil test based on the sand cone method are commonly used to measure the degree of compaction, but many other methods are under development as it is difficult to secure economic efficiency. For the purpose of this research, a portable penetration meter called the Free-Fall Penetration Test (FFPT) was developed and manufactured. In this study, a homogeneous sample was obtained from the construction site and soil was classified through a sieve analysis test in order to perform grain size analysis and a specific gravity test for an indoor test. The principle of FFPT is that the penetration needle installed at the tip of an object put into free fall using gravity is used to measure the depth of penetration into the road surface after subgrade or roadbed compaction has been completed; the degree of compaction is obtained through the unit weight of soil test according to the sand cone method and the relationship between the degree of compaction and the depth of the penetration needle is verified. The maximum allowable grain size of soil is 2.36 mm. For $A_1$ compaction, a trend line was developed using the result of the test performed from a drop height of 10 cm, and coefficient of determination of the trend line was $R^2=0.8677$, while for $D_2$ compaction, coefficient of determination of the trend line was $R^2=0.9815$ when testing at a drop height of 20 cm. Free fall test was carried out with the drop height adjusted from 10 cm to 50 cm at increments of 10 cm. This study intends to compare and analyze the correlation between the degree of compaction obtained from the unit weight of soil test based on the sand cone method and the depth of penetration of the penetration needle obtained from the FFPT meter. As such, it is expected that a portable penetration tester will make it easy to test the degree of compaction at many construction sites, and will lead to a reduction in time, equipment, and manpower which are the disadvantages of the current degree of compaction test, ultimately contributing to accurate and simple measurements of the degree of compaction as well as greater economic feasibility.

A study on Indoor Insulating Tent Design for Senior Citizens who Live Alone (독거노인을 위한 융복합 실내 보온용 텐트디자인에 관한 연구)

  • Lee, Dae Hyun;Kim, Sang Sik
    • Korea Science and Art Forum
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    • v.37 no.2
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    • pp.219-230
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    • 2019
  • According to the National Statistical Office, the number of senior citizens aged 65 or over has exceeded 7 million as of 2017, and the number of senior citizens who live alone among them exceeded 1.3 million. Most of the senior citizens who live alone suffer from absolute poverty (68.5% of them has monthly income less than 500,000 won) and they have difficulties for basic living in the blind spot of our society. In particular, the heating is quite a serious issue for the senior citizens who live alone and belong to vulnerable social group in the winter, and to make it worse, they are exposed to frequent fire accidents due to the negligence in handling electric appliances such as electric heaters and electric pads. The main reason the indoor tent products are being used by senior citizens who live alone is that it saves energy, ensures warm sleep, and improves fire safety. Following the expansion of the indoor tent market, this study focused on the idea that there is a need for an in door tent suitable for senior citizens who live alone and belong to low income bracket and intended to improve its efficiency in relation to use, resting, and storage. For this, a basic survey was conducted on the products of existing brands to analyze advantages and disadvantages and it was possible to understand the demands that consumers have for existing products. Accordingly, a survey on consumer preference was conducted using a designed model and the Zabara typp, which demonstrated the best efficiency in terms of installation convenience, space usability, and appearance design was selected. Based on the results of selection, the product design and final prototype were completed. The results and details of the study are as follows; First, factors that were not recognized in product development phase could be identified through usability survey and interview with actual users. Second, for the effective aspect of the prototype, senior citizens could install and fold the tend more easily and quickly than expected. Based on these results of this study, it is expected that not only senior citizens who live alone but also various other users can use the tent to create another comfortable private space indoors.

Designing and Fabricating of the High-visibility Smart Safety Clothing (고시인성 스마트 안전의류의 설계 및 제작)

  • Park, Soon-Ja;Kim, Sun-Woong
    • Science of Emotion and Sensibility
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    • v.23 no.4
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    • pp.105-116
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    • 2020
  • The purpose of this study is to progress the limitations and disadvantages of existing safety clothing by applying high technology to current safety clothing that is produced and distributed only with fluorescent fabrics and retroreflective materials. Therefore, the industrial suspender-type safety belt and engineering technology are introduced, designed, and fabricated to help save a life in an emergency. First, the suspender-type safety belt to be developed is designed to emit light by LED attached to the film, and the body of the belt-wearer is recognized from a distance through retroreflection from the flashing LED. It aims to support people's safety by preventing accidents during roadside work, rescue activities, and sports activities at night. Second, with the development of advanced devices when the user is in an unconscious state due to distress or falls into an unconscious state due to distress or accident, the tilt sensor of the control unit attached to the belt automatically detects the angle of the human body and generates light and sound. It is intended to further enhance the utilization by mounting a sensing and signaling device that generates a distress signal and shaping it in the form of a belt attached to a vest that can be easily detached from the outside of the garment. When the wearer falls due to an accident, the tilt sensor of this belt detects the angle change and then the controller generates a high-frequency sound and repeated LED blinking signals at the same time. In the case of conventional safety vests, it is almost impossible to detect that the person is wearing a vest when there is no ambient light, but in case of the safety belts in this study, the sound and light signals of the safety belt enable us to find the wearer within 100 meters even when there is no ambient light.

Development of Stand Yield Table Based on Current Growth Characteristics of Chamaecyparis obtusa Stands (현실임분 생장특성에 의한 편백 임분수확표 개발)

  • Jung, Su Young;Lee, Kwang Soo;Lee, Ho Sang;Ji Bae, Eun;Park, Jun Hyung;Ko, Chi-Ung
    • Journal of Korean Society of Forest Science
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    • v.109 no.4
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    • pp.477-483
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    • 2020
  • We constructed a stand yield table for Chamaecyparis obtusa based on data from an actual forest. The previous stand yield table had a number of disadvantages because it was based on actual forest information. In the present study we used data from more than 200 sampling plots in a stand of Chamaecyparis obtusa. The analysis included theestimation, recovery and prediction of the distribution of values for diameter at breast height (DBH), and the result is a valuable process for the preparation ofstand yield tables. The DBH distribution model uses a Weibull function, and the site index (base age: 30 years), the standard for assessing forest productivity, was derived using the Chapman-Richards formula. Several estimation formulas for the preparation of the stand yield table were considered for the fitness index, and the optimal formula was chosen. The analysis shows that the site index is in the range of 10 to 18 in the Chamaecyparis obtusa stand. The estimated stand volume of each sample plot was found to have an accuracy of 62%. According to the residuals analysis, the stands showed even distribution around zero, which indicates that the results are useful in the field. Comparing the table constructed in this study to the existing stand yield table, we found that our table yielded comparatively higher values for growth. This is probably because the existing analysis data used a small amount of research data that did not properly reflect. We hope that the stand yield table of Chamaecyparis obtusa, a representative species of southern regions, will be widely used for forest management. As these forests stabilize and growth progresses, we plan to construct an additional yield table applicable to the production of developed stands.

Idea of Jurye Shown on GyeongJeMunGam and GyeongJeMunGamByeolJip (『경제문감(經濟文鑑)·별집(別集)』에 나타난 주례(周禮) 이념)

  • Kim, In-Gyu
    • (The)Study of the Eastern Classic
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    • no.69
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    • pp.563-592
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    • 2017
  • This paper is to examine philosophy of Jurye(周禮, national rituals) described on GyeongJeMunGam and GyeongJeMunGamByeolJip. As it is widely known, Sambong Jeong Do-Jeon (三峯 鄭道傳), regardless of evaluation by posterity, is definitely a figure who established 500 years of Joseon with almost everything handled by his own hands from presenting founding principle of Joseon to organizing the bureaucratic system. In the third year of King Taejo (1394) with Jurye as an ideological model for social innovation, Jeong Do-Jeon wrote Joseongyeonggukjeon and offered it to the king. Joseongyeonggukjeon is a sort of guide for new codes written by Jeong Do-Jeon as a part of defining culture and institutions of the new dynasty, which is based on Confucianism, the ruling idea of the new dynasty. GyeongJeMunGam supplements the section ChiJeon(治典: Articles for Governing) of JoSeonGyeongGukJeon(the first constitution of Joseon Dynasty) mainly to specify the duties and jobs of the prime minister; and also the duties and jobs of the highest secretaries of the kings, and provincial and county governors, whereas GyeongJeMunGamByeolJip consists of the section GunDo specifying the duties and jobs of the kings and the section Euiron additionally explaining about the kings' duties and jobs in the viewpoint of the philosophy of the Book of Change. That is, GyeongJeMunGam finely describes not only the changes, advantages and disadvantages of prime minister system of every dynasty of China and Korea but also the prime minister's duties/jobs and attitude for kings; and it also specifies the duties and jobs of the kings' highest secretaries, guards, provincial and county governors; on the other hand, GyeongJeMunGamByeolJip says that the king should play the symbolic figure setting their mind in right ways and train themselves with virtue through the idea of GunJuSuShin (君主修身: ) to point out a good and capable prime minister and make him govern the country without using their power fully.

Analysis the Appropriate Schedule for the Installment Payment Amount and Establishment of the Post sale System and Policy in the Apartment Construction (공동주택 건설사업에서 후분양의 제도 및 정책 수립을 위한 분담금 납부 적정시기 분석)

  • Yoon, Inhwan;Bae, Byungyun
    • Korean Journal of Construction Engineering and Management
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    • v.22 no.4
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    • pp.59-65
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    • 2021
  • Since the 2016 "Housing Act Partial Amendment" and the "2018 Housing Comprehensive Amendment Plan", interest in the pre sale system and post sale system of apartment houses has been on the rise. In order to compare the advantages and disadvantages of the pre sale system and the post sale system of apartment houses, and to establish the basis for the institutional policy of the post sale system, a questionnaire survey method was used for tenants of the apartment house from the public side, and issues of time and cost. The time series analysis method is intended to suggest an appropriate time for payment of contributions. Accordingly, through a review of existing theories and literature, the post sale system of public and private institutions was organized, and through a questionnaire survey, the path to securing pre sale money, product information of the model house, and the degree of awareness of the effect of the post sale system were investigated. For the post sale fund support and payment method, it is necessary to increase the commercial line for existing financiers from the user's point of view, and it is necessary to operate in consideration of the economic power of the pre sale market by region. Both 60% post sale and 80% post sale have a price range of up to KRW 10 million, and the total interest rate is 5.0%, and the annual interest rate is about 2.8% for 60% post sale, and about 2.1% for 80% post sale, which is lower than the current 3.1%. I need an interest rate. The research is a perception survey targeting a total of 5,213 households in a sample of after sale apartments in public institutions. As the actual values are analyzed using a time series on the effects of market supply and demand and market prices, there is a limit to applying them to prospective residents of private apartments. In addition, to respond to first time tenants, a questionnaire survey was conducted on five complexes that have moved in within the last five years.

Analysis of Skin Color Pigments from Camera RGB Signal Using Skin Pigment Absorption Spectrum (피부색소 흡수 스펙트럼을 이용한 카메라 RGB 신호의 피부색 성분 분석)

  • Kim, Jeong Yeop
    • KIPS Transactions on Software and Data Engineering
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    • v.11 no.1
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    • pp.41-50
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    • 2022
  • In this paper, a method to directly calculate the major elements of skin color such as melanin and hemoglobin from the RGB signal of the camera is proposed. The main elements of skin color typically measure spectral reflectance using specific equipment, and reconfigure the values at some wavelengths of the measured light. The values calculated by this method include such things as melanin index and erythema index, and require special equipment such as a spectral reflectance measuring device or a multi-spectral camera. It is difficult to find a direct calculation method for such component elements from a general digital camera, and a method of indirectly calculating the concentration of melanin and hemoglobin using independent component analysis has been proposed. This method targets a region of a certain RGB image, extracts characteristic vectors of melanin and hemoglobin, and calculates the concentration in a manner similar to that of Principal Component Analysis. The disadvantage of this method is that it is difficult to directly calculate the pixel unit because a group of pixels in a certain area is used as an input, and since the extracted feature vector is implemented by an optimization method, it tends to be calculated with a different value each time it is executed. The final calculation is determined in the form of an image representing the components of melanin and hemoglobin by converting it back to the RGB coordinate system without using the feature vector itself. In order to improve the disadvantages of this method, the proposed method is to calculate the component values of melanin and hemoglobin in a feature space rather than an RGB coordinate system using a feature vector, and calculate the spectral reflectance corresponding to the skin color using a general digital camera. Methods and methods of calculating detailed components constituting skin pigments such as melanin, oxidized hemoglobin, deoxidized hemoglobin, and carotenoid using spectral reflectance. The proposed method does not require special equipment such as a spectral reflectance measuring device or a multi-spectral camera, and unlike the existing method, direct calculation of the pixel unit is possible, and the same characteristics can be obtained even in repeated execution. The standard diviation of density for melanin and hemoglobin of proposed method was 15% compared to conventional and therefore gives 6 times stable.

A Study on the Major Issues and Legislative Considerations of CCTV Installation in an Operating Room (수술실 CCTV 설치의 쟁점과 입법방향에 관한 소고(小考))

  • Kim, Sungeun;Choe, A Reum;Bae, Kyounghee
    • The Korean Society of Law and Medicine
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    • v.22 no.2
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    • pp.111-138
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    • 2021
  • 'Unlicensed medical practice by a non-medical practitioner' often represented by surrogate surgery or so-called 'ghost surgery,' causes irreparable damage to life or body, and therefore calls for very strict and effective controls. The 'bill on installment of CCTVs in an operating room' to prevent unlicensed surrogate surgery has been discussed for a long time, but due to numerous issues and heated confrontations, it has been pending in the National Assembly. Nevertheless, it is expected that the bill will be discussed again in earnest in the National Assembly because surrogate surgery and factory-type cosmetic surgery, which has been performed mainly in the field of cosmetic surgery, has also been occurring in the field of therapeutic surgery. In general, an operating room is considered as being locked or closed, as well as disallowing implicit complicity among insiders. Hence, if the insiders conspire to commit or cover up an illegal act, or if a surgeon performs rapid cosmetic surgery and then leaves the recipient (or medical institution) so as to perform more operations for profit - even if it is legitimate practice - it may result in serious consequences in terms of the recovery of a patient. In this case, installation of CCTVs can be of great help in identifying an illegal act and assessing any occurrence of negligence. On the other hand, while the fundamental purpose of therapeutic surgery is to restore a patient's life or body - that is, lifesaving - installation of CCTVs may base the relationship between a surgeon and a patient on distrust and surveillance, so it may increase the number of requests for CCTV footage or lead to more disputes, as well as placing a burden on the surgeon when best results are not achieved for a patient. As a result, the surgeon may choose non-invasive treatment contrary to conscience instead of risky but necessary surgery, or he/she may have significant difficulty in determining the timing of surgery, which may limit the provision of effective surgical medical care. Then, in terms of the relationship between a surgeon and patient, and in the long run, there could be significant disadvantages for the public and patients if CCTV footage is allowed. In this paper, we review domestic and overseas cases and issues regarding installation of CCTVs in an operating room, and present various viewpoints and suggestions to promote legislation with minimized legal problems and side effects, thereby contributing to protection of the lives and health of the public, patients, and recipients of surgery.