• Title/Summary/Keyword: construction control

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An Effect of Revolutions Per Minute (r.p.m) in the Noise Characteristics (기계소(機械騷) 음(音)과 회전(回轉) 속도(速度))

  • Cha, Bong-Suk
    • Journal of Preventive Medicine and Public Health
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    • v.10 no.1
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    • pp.94-101
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    • 1977
  • Noise pollution, both in the environment and in the workplace, has been recognized as a major health hazard -one that can impair not only a person's hearing but also his physical and mental well-being. As industrialization progresses, the prevalence rate of occupational diseases is increasing, especially hearing loss, which has the highest prevalence rate among the occupational diseases. The major cause of noise is the construction of various large industries without any regulation of noise sources. Therefor, we must establish an enactment to control mechanical noise sources. as soon as possible. For the purpose of controlling the noise source, we must have exact data about such things as the sound level, the frequency of the peak sound and the revolutions per minute (r.p.m.) of the machine (a measure of the power of its motor). This study was undertaken in order to define the noise characteristics, the power of the machine's motor, the change of the sound level and the peak sound as the r.p.m. increases, and the permissible exposure time. The sample size of this study was 74 machines at 11 plants in 6 industries. The results are as follows; 1. The breakdown of the types of mechanical noise noted was : 63.6% continuous normal sound, 26.9% intermittent sound, 4.7% continuous repeating sound and 4.6% impulsive sound. 2. With respect to the type of industry, the overall sound level was the highest in the mechanical industry, with $103.8{\pm}2.8dB(A)$, and lowest in the textile industry, with $89.2{\pm}1.43dB(A)$. 3. With respect to the type of machine, the highest sound level was 124 dB(A) caused by Gauzing(II), in the mechanical industry, and the lowest was 76 dB(A) caused by Attachment (Jup Chack) (I) in the timber industry. 4. The shortest permissible exposure time to Gauzing(II) in the mechanical industry was less than 15 minutes. 5. Among 74 machines, 68.2% of the peak sound was situated in the high frequency range (52.7% at 2 KHz, 4.1% at 4 KHz and 1.4% at 8 KHz). 41.8% of the peak sound was in the middle frequency range (4.1% at 250Hz, 14.8% at 500Hz and 22.9% at 1KHz). 6. If one machine had two motors or more, the peak sound was shifted to the low frequency range. 7. As the r.p.m. increased, the overall and peak sound levels were increased without any change of the frequency of the peak sound. 8. Whenever the machines had the same kind and the same r.p.m., the overall and peak sounds were changed by the physicochemical characteristics of the raw materials and the management.

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Studies on the Press Drying and the Chemical Absorption of the Plywood Treated with Diammonium Phosphate (제2인산(第2燐酸)암모늄 처리합판(處理合板)의 약제흡수(藥劑吸收) 및 열판건조(熱板乾燥)에 관(關)한 연구(硏究))

  • Kim, Jong-Man
    • Journal of the Korean Wood Science and Technology
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    • v.23 no.4
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    • pp.39-45
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    • 1995
  • The plywoods commonly used as decorative interior materials for the construction are inflammable and so it is a causative factor for making fire accidents, resulting in the destruction of human life and personal properties. Indeed, it is, therefore, required to produce fire-retardant plywoods. In this study, a special grade of defect-free, Kapur plywood was used. Specimens were cut into 3- by 20cm dimensions from 120- by 240- by 0.33-cm panels(thin panel) or 120- by 240- by 0.5-cm panels(thick panel). Some specimens were treated with diammonium phosphate(DAP), but some were not treated with diammonium phosphate to use as control panels. Chemical absorption, drying curves, drying rates and dynamic Young's modulus were investigated. The results were summaries as follows; 1. The specimens were soaked into 19% diammonium phosphate solution by a full cell pressure process and the diammonium phosphate retained in the thin and thick plywoods was 1.409kg/$(30cm)^3$, 1.487kg/$(30cm)^3$, respectively. 2. Diammonium phosphate-treated plywoods were redried with press-drying process at one of either condition dried on the platen($115^{\circ}C$) for a period of time or dried on the platen($50^{\circ}C$) for 3 hrs plus in a dry-oven($30^{\circ}C$) for 24 hrs. or dried on the platen($60^{\circ}C$) for 2 hrs plus in a dry-oven($30^{\circ}C$) for 24 hrs. The drying rate of treated thin specimens dried at $60^{\circ}C$ plus $30^{\circ}C$ and $115^{\circ}C$ only was found to be 0.04 %/min. and 8.53 %/min. Similarly, the drying rate of treated thick specimens were 0.03 %/min. and 6.77 %/min. respectively. 3. It was evident that highly-significantly different drying rate of treated plywoods was observed between plywood thicknesses and platen temperatures and the rate was increased by elevating the platen temperature up to $115^{\circ}C$. Based on the two-way variance analysis, highly significant drying rate was observed from the interaction between plywood thicknesses and platen temperatures. 4. After redrying, the specimens were weighed and reconditioned to a constant weight in a facility maintained temperature ($20^{\circ}C$) and relative humidity(65%) prior to test dynamic Young's modulus. The test revealed that the thin specimens dried at the platen temperature of $50^{\circ}C$, $60^{\circ}C$, $115^{\circ}C$ and untreated specimens showed 1.070E+09 dyne/$cm^2$, 1.156E+09 dyne/$cm^2$, 1.243E+09 dyne/$cm^2$, and 1.052E+09 dyne/$cm^2$, respectively. Likewise, the thick specimens revealed 5.647E+09 dyne/$cm^2$ 5.670E+09 dyne/$cm^2$, 6.395E+09 dyne/$cm^2$ and 5.415E+09 dyne/$cm^2$, respectively. 5. It was evident that significantly different dynamic Young's modulus was observed between the plywood thickness and the platen temperature, but not in the two-way interaction between the plywood thickness${\times}$the platen temperature.

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The introduction of a criminal case arbitration on premise the civil and commercial arbitration (민상사(民商事) 중재제도(仲裁制度)를 전제(前提)로 한 형사중재제도(刑事仲裁制度)의 도입방안(導入方案))

  • Nam, Seon-Mo
    • Journal of Arbitration Studies
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    • v.19 no.3
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    • pp.93-119
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    • 2009
  • Nowadays the number of crimes is increasing rapidly and society is getting more and more dangerous. Recently the criminal aspect of our society, the intelligence, diversity, localized area, as well as for the crime victims also difficult to predict the damage recovery is not easy to change their level of pain and are also serious. This phenomenon is increasingly expected to intensify, the proper response is a factory. The more so if the victim of murder. The criminal mediation working on the operational adjustments Borrower payment, Construction charges, investments and financial transactions due to interpersonal conflicts that occurred as a fraud, embezzlement, breach of trust property crimes such accused, individuals between the defamatory, offensive, encroachment, violating intellectual property rights and private Disputes about the complaint case and other criminal disputes submitted to mediation to resolve it deems relevant to the case who are accused. But the core of a detective control adjustment, adjust the members' representative to the region, including front-line player or a lawyer appointed by the attorney general at this time by becoming parties to this negative view may be ahead. Some scholars are criticizing the current criminal justice system for the absence of proper care for the criminal victims, as an alternative to the traditional criminal justice system. The introduction of the summary trial and related legal cases, the command structure, compensation system, crime victims' structural system can be seen as more classify, crime subject to victim's complaint, By case with a criminal misdemeanor in addition to disagree not punish criminal, minor offense destination, traffic offenders, regular property crime, credit card theft, intellectual property rights violators can be seen due to more categories can try. They sued in law enforcement, Prosecution case has been received and if any one party to the criminal detective Arbitration request arbitration by the parties can agree to immediately contact must be referred to arbitration within 15 days of when the arbitration case will be dismissed. These kinds of early results of the case related to, lawyers are involved directly in the arbitration shall be excluded. Arbitration system is the introduction of criminal justice agencies working to help resolve conflicts caused by adjustment problems will be able to. This article does not argue that we should stick to the traditional justice system as a whole. Instead it argues that the restrictive role of the traditional justice is to be preserved.

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Developing Forest Fire Status Information Management System using Web GIS Technology (웹 지리정보시스템 기술을 이용한 산불 현황정보 관리시스템 개발)

  • Jo, Myung-Hee;Kim, Joon-Bum;Kim, Hyun-Sik;Jo, Yun-Won
    • Journal of the Korean Association of Geographic Information Studies
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    • v.5 no.4
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    • pp.93-105
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    • 2002
  • In this paper forest fire status information management system was developed under web environment using web GIS(geographic information system) technology. Though this system, general users can easily retrieval domestic forest fire status information and obtain that in visual way such as maps, graphs, and texts if they have only certain web browsers. Moreover, officials, who have system access authority, can easily control and manage all domestic forest fire status information through input interface, retrieval interface, and out interface of the system. This system can be considered as the first domestic system to manage forest fire status data and service them in visual through user friendly interfaces on web. In order to implement this system, IIS 5.0 of Microsoft is used as web server and Oracle 8i and ASP(active server page) are used for database construction and dynamic web page operation, respectively. Also, ArcGIS IMS(internet map server) of ESRI is used to serve maps by using Java and HTML as system development languages. Not only the domestic tendency of forest fire but also the forest fire status information of certain area and time such as the frequency and the loss can be presented through distribution maps, graphs and tables. Therefore, this system is supposed to play as a important role when the policy relate to domestic forest fire is established. In addition, the self consciousness of people against forest fire can be inspired and the foundation of scientific and systemic forest fire services can be obtained through this system in the future.

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A 0.4-2GHz, Seamless Frequency Tracking controlled Dual-loop digital PLL (0.4-2GHz, Seamless 주파수 트래킹 제어 이중 루프 디지털 PLL)

  • Son, Young-Sang;Lim, Ji-Hoon;Ha, Jong-Chan;Wee, Jae-Kyung
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.12
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    • pp.65-72
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    • 2008
  • This paper proposes a new dual-loop digital PLL(DPLL) using seamless frequency tracking methods. The dual-loop construction, which is composed of the coarse and fine loop for fast locking time and a switching noise suppression, is used successive approximation register technique and TDC. The proposed DPLL in order to compensate the quality of jitter which follows long-term of input frequency is newly added cord conversion frequency tracking method. Also, this DPLL has VCO circuitry consisting of digitally controlled V-I converter and current-control oscillator (CCO) for robust jitter characteristics and wide lock range. The chip is fabricated with Dongbu HiTek $0.18-{\mu}m$ CMOS technology. Its operation range has the wide operation range of 0.4-2GHz and the area of $0.18mm^2$. It shows the peak-to-peak period jitter of 2 psec under no power noise and the power dissipation of 18mW at 2GHz through HSPICE simulation.

The Distribution and Characteristics of Geographical Names on 1:50,000 Topographic Map of the Korean Peninsula in the Early 20th Century ("오만분일지형도(五萬分一地形圖)"에 나타난 20세기 초 한반도의 지명 분포와 특성)

  • Kim, Sun-Hee
    • Journal of the Korean Geographical Society
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    • v.43 no.1
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    • pp.87-103
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    • 2008
  • The geographical name is an expression of human knowledge about living conditions and a basic tool for understanding about regional cultures and history as a result of spatiotemporal changes. This study aims to understand the historical and regional characteristics by analyzing the frequency and distribution of geographical names of 1:50,000 topographic map in the early 20th century and materializing on electronic cultural atlas. The result of this analysis is as follows. First, the aspect of distributed geographical names on the Korean Peninsula reflects a general trait of the country's natural and human environment included geographical features, population, arable land, the number of counties and villages, and functions of administration and military, etc. Second, through the frequency and weight of their names, the analysis shows not only the change of native names, but also the country's phase of the time by Japanese colonial policies such as exploitation of resources, the construction of railroads, and a desire to control of the border area with Manchuria. In addition, the study identified regional characteristics and differences in environmental perception and preferences, and naming basis and forms by the comparative analysis of each type of geographical names associated with village and ridge such as 'Chi' 'Ryung' 'Duk' 'Hang' 'Pyeong' 'Gok'. In particular, those characteristics were largely affected from environmental difference of each area.

EST Analysis system for panning gene

  • Hur, Cheol-Goo;Lim, So-Hyung;Goh, Sung-Ho;Shin, Min-Su;Cho, Hwan-Gue
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2000.11a
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    • pp.21-22
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    • 2000
  • Expressed sequence tags (EFTs) are the partial segments of cDNA produced from 5 or 3 single-pass sequencing of cDNA clones, error-prone and generated in highly redundant sets. Advancement and expansion of Genomics made biologists to generate huge amount of ESTs from variety of organisms-human, microorganisms as well as plants, and the cumulated number of ESTs is over 5.3 million, As the EST data being accumulate more rapidly, it becomes bigger that the needs of the EST analysis tools for extraction of biological meaning from EST data. Among the several needs of EST analyses, the extraction of protein sequence or functional motifs from ESTs are important for the identification of their function in vivo. To accomplish that purpose the precise and accurate identification of the region where the coding sequences (CDSs) is a crucial problem to solve primarily, and it will be helpful to extract and detect of genuine CD5s and protein motifs from EST collections. Although several public tools are available for EST analysis, there is not any one to accomplish the object. Furthermore, they are not targeted to the plant ESTs but human or microorganism. Thus, to correspond the urgent needs of collaborators deals with plant ESTs and to establish the analysis system to be used as general-purpose public software we constructed the pipelined-EST analysis system by integration of public software components. The software we used are as follows - Phred/Cross-match for the quality control and vector screening, NCBI Blast for the similarity searching, ICATools for the EST clustering, Phrap for EST contig assembly, and BLOCKS/Prosite for protein motif searching. The sample data set used for the construction and verification of this system was 1,386 ESTs from human intrathymic T-cells that verified using UniGene and Nr database of NCBI. The approach for the extraction of CDSs from sample data set was carried out by comparison between sample data and protein sequences/motif database, determining matched protein sequences/motifs that agree with our defined parameters, and extracting the regions that shows similarities. In recent future, in addition to these components, it is supposed to be also integrated into our system and served that the software for the peptide mass spectrometry fingerprint analysis, one of the proteomics fields. This pipelined-EST analysis system will extend our knowledge on the plant ESTs and proteins by identification of unknown-genes.

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The Application of Adaptive Network-based Fuzzy Inference System (ANFIS) for Modeling the Hourly Runoff in the Gapcheon Watershed (적응형 네트워크 기반 퍼지추론 시스템을 적용한 갑천유역의 홍수유출 모델링)

  • Kim, Ho Jun;Chung, Gunhui;Lee, Do-Hun;Lee, Eun Tae
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.5B
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    • pp.405-414
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    • 2011
  • The adaptive network-based fuzzy inference system (ANFIS) which had a success for time series prediction and system control was applied for modeling the hourly runoff in the Gapcheon watershed. The ANFIS used the antecedent rainfall and runoff as the input. The ANFIS was trained by varying the various simulation factors such as mean areal rainfall estimation, the number of input variables, the type of membership function and the number of membership function. The root mean square error (RMSE), mean peak runoff error (PE), and mean peak time error (TE) were used for validating the ANFIS simulation. The ANFIS predicted runoff was in good agreement with the measured runoff and the applicability of ANFIS for modelling the hourly runoff appeared to be good. The forecasting ability of ANFIS up to the maximum 8 lead hour was investigated by applying the different input structure to ANFIS model. The accuracy of ANFIS for predicting the hourly runoff was reduced as the forecasting lead hours increased. The long-term predictability of ANFIS for forecasting the hourly runoff at longer lead hours appeared to be limited. The ANFIS might be useful for modeling the hourly runoff and has an advantage over the physically based models because the model construction of ANFIS based on only input and output data is relatively simple.

A numerical study of pillar reinforcing effect in underground cavern underneath existing structures (지하공간하부 지하저류공동에서의 필라 보강효과에 관한 수치해석적 연구)

  • Seo, Hyung-Joon;Lee, Kang-Hyun;Han, Shin-In;Lee, In-Mo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.14 no.5
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    • pp.453-467
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    • 2012
  • Usage of underground space is increasing at metropolitan city. More than 90% of flood damages have occurred at downtown of metropolitan cities. In order to prevent and/or minimize the flood-induced damage, an underground rainwater detention cavern was proposed to be built underneath existing structures. As for underground caverns to be built for flood control, multi-caverns will be mostly adopted rather than one giant cavern because of stability problem. Because of the stress concentration occurring in the pillars between two adjacent caverns, the pillar-stability is the Achilles' heel in multi-caverns. So, a new pillar-reinforcing technology was proposed in this paper for securing the pillar-stability. In the new pillar-reinforcing technology, reinforced materials which are composed of a steel bar and PC strands are used by applying pressurized grouting, and then, by applying the pre-stress to the PC strands and anchor body. Therefore, this new technology has an advantage of utilizing most of the strength that the in-situ ground can exert, and not much relying on the pre-cast concrete structure. The main effect of the pressurized grouting is the increase of the ground strength and more importantly the decrease of stress concentration in the pillar; that of the pre-stress is the increase of the ground strength due to the increase of the internal pressure. In this paper, ground reinforcing effects were verified the stress change in pillar is obtained by numerical analysis at each construction stage. From these results, the effects of pressurized grouting and pre-stress are verified.

Flexural Strength Evaluation of Steel Plate-Concrete Composite Beam using Bolted (절곡 강판을 볼트로 체결한 강판-콘크리트 합성보의 휨강도 평가)

  • Han, Myoung-Hwan;Choi, Byong-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.126-136
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    • 2018
  • A steel-plate concrete composite beam is composed of a steel plate, concrete and shear connector to combine inhomogeneous two materials. The steel plate is assembled by welding an existing composite beam. In this study, new steel-plate concrete composite beam, called a SPC Beam, was developed to reduce the shear connector and improve the workability. The SPC Beam was composed of folding steel plates and concrete, without a shear connector. The folding steel plate was assembled using high strength bolt instead of welding. To improve the workability in field construction, a hat-shaped Cap was attached to the junction with a slab. Monotonic load testing under two points was conducted under displacement control mode. The flexural strength of the specimen for positive moment and negative moment was calculated using the plastic stress distribution method. The test results showed that the flexural strength of the new SPC Beam had 80% of the strength of a complete composite beam. In addition, increasing the composite ratio was possible through clearance controls of the cap. In this study, the performance of the SPC Beam was verified through additional experiments and analyses with the cross-sectional shape and cap as variables, because the representative shape in the positive negative moment region is targeted.