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Computation of geographic variables for air pollution prediction models in South Korea

  • Eum, Youngseob;Song, Insang;Kim, Hwan-Cheol;Leem, Jong-Han;Kim, Sun-Young
    • Environmental Analysis Health and Toxicology
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    • v.30
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    • pp.10.1-10.14
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    • 2015
  • Recent cohort studies have relied on exposure prediction models to estimate individual-level air pollution concentrations because individual air pollution measurements are not available for cohort locations. For such prediction models, geographic variables related to pollution sources are important inputs. We demonstrated the computation process of geographic variables mostly recorded in 2010 at regulatory air pollution monitoring sites in South Korea. On the basis of previous studies, we finalized a list of 313 geographic variables related to air pollution sources in eight categories including traffic, demographic characteristics, land use, transportation facilities, physical geography, emissions, vegetation, and altitude. We then obtained data from different sources such as the Statistics Geographic Information Service and Korean Transport Database. After integrating all available data to a single database by matching coordinate systems and converting non-spatial data to spatial data, we computed geographic variables at 294 regulatory monitoring sites in South Korea. The data integration and variable computation were performed by using ArcGIS version 10.2 (ESRI Inc., Redlands, CA, USA). For traffic, we computed the distances to the nearest roads and the sums of road lengths within different sizes of circular buffers. In addition, we calculated the numbers of residents, households, housing buildings, companies, and employees within the buffers. The percentages of areas for different types of land use compared to total areas were calculated within the buffers. For transportation facilities and physical geography, we computed the distances to the closest public transportation depots and the boundary lines. The vegetation index and altitude were estimated at a given location by using satellite data. The summary statistics of geographic variables in Seoul across monitoring sites showed different patterns between urban background and urban roadside sites. This study provided practical knowledge on the computation process of geographic variables in South Korea, which will improve air pollution prediction models and contribute to subsequent health analyses.

Practice and Research Development of Technology Innovation in China

  • Wang, Zong-Jun;Wang, Xin-Xin;Wu, Yu-Qiong;Zhao, Yun-Long;Yang, Ping
    • Proceedings of the Korea Technology Innovation Society Conference
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    • 2006.11a
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    • pp.15-41
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    • 2006
  • The increasing popularity of the concept of technology innovation has been driven by greater international competition in a rapidly globalizing economy. Both countries and enterprises are placing more and more emphasis on it in order to gain competitive advantages. This article gives a general introduction about the research and application of technology innovation in China. At the national level, one obvious fact is that the total R&D expenditure increased rapidly during the year 2001 to year 2005 and reached Y 245 billions, and China made 2,452 international patent applications in 2005 and became the world's 10th largest user of the Patent Cooperation Treaty. At the industry and enterprise level, much progress has also been made in China. This article uses the high-tech industry as an example to introduce the industry and enterprise technology innovation respectively. Corresponding to the practice, scholars also did a great amount of research work related to technology innovation. This article sums up all the work done from the macroscopic aspect (such as national technology innovation strategy, regional innovation system, industry technology innovation) and microcosmic aspect (such as enterprise technology innovation strategy, patterns and evaluation standards). Based on the analysis, this article discusses the limitation of current work and research trend about the technology innovation.

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A Study on Some Major Clauses of a Payment Guarantee in International Transactions (국제거래에서 대금지급보증서(payment guarantee)의 주요 조항에 대한 연구)

  • Kim, Sang Man
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.58
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    • pp.179-213
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    • 2013
  • While a performance type guarantee is required as a security for non-performance risk by a seller, a payment guarantee is used as a security for non-payment risk by a buyer(or a borrower in a loan agreement). A payment guarantee is a type of independent bank guarantee, bank guarantee, bond, demand guarantee, or standby letter of credit. A guarantor accepts a credit risk of a principal which is normally a buyer in a contract for sale of goods. A payment guarantee is independent of the underlying relationship between the applicant and the beneficiary. The guarantor is only empowered to examine the beneficiary's demand and determine the payment on its face to the terms of the guarantee. A payment guarantee is thus different from a suretyship. The principle of independence carries a significant advantages for a guarantor as well as for a beneficiary. While a documentary credit requires B/L, commercial invoice, packing list, inspection certificate, etc., a typical payment guarantee does not require any evidence for a seller's performance of the underlying contract other than written demand. In this respect payment guarnatee can be a more secured facility than a documentary credit. A payment guarantee normally comes into force from the issuing date and shall remain in effect until all sums guaranteed shall be paid in full by a buyer(or a borrower) or by a guarantor. Although a guarantor shall pay a demand made in accordance with the terms and conditions of the payment guarantee, a payment demand may be denied when it is determined to be abusive or unfair.

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A Boolean Factorization Using an Extended Two-cube Matrix (확장된 2-큐브 행렬을 이용한 부울 분해식 산출)

  • Kwon, Oh-Hyeong;Oh, Im-Geol
    • Journal of the Korea Computer Industry Society
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    • v.8 no.4
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    • pp.229-236
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    • 2007
  • A factored form is a sum of products of sums of products, ..., of arbitrary depth. Factoring is the process of deriving a parenthesized form with the smallest number of literals from a two-level form of a logic expression. The factored form is not unique and described as either algebraic or Boolean. A Boolean factored form contains fewer number of literals than an algebraic factored form. In this paper, we present a new method for a Boolean factorization. The key idea is to identify two-cube Boolean subexpressions from given two-level logic expression and to extract divisor/quotient pairs. Then, we derive extended divisor/quotient pairs, where their quotients are not cube-free, from the generated divisor/quotients pairs. We generate quotient/quotient pairs from divisor/quotient pairs and extended divisor/quotient pairs. Using the pairs, we make a matrix to generate Boolean factored form based on a technique of rectangle covering.

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Properties of a Lactobacillus acidophilus Bacteriocin (Lactobacillus acidophilus Bacteriocin의 성상에 관한 연구)

  • 정영건;안장연;권오진;강주회
    • Microbiology and Biotechnology Letters
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    • v.17 no.2
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    • pp.94-99
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    • 1989
  • Seven gtrains of Lactobacillus produce bacteriocin being active for Lacidophilus. All strains producing bacteriocin were found to be L. acidophilus except with one strain of L. gasseri. The maximum activity of bacteriocin produced by Lactobacillus strains was obtained at a middle or late stage of the log phase, or a early stage of the stationary phase. After the maximum was reached, however, the activity was rapidly decreased. The bacteriocins were inactivated easily by the treatment with proteolytic enzymes but not with nucleolytic enzymes, suggesting that the bacteriocin was proteinaceous. The bacteriocins were different from the other previously reported lactobacillus bacteriocin in their flexibility to the treatment at 10$0^{\circ}C$. Bacteriocins of L. acidophilus ATCC 9857 and 4357 decreased in activity by the treatment with diethylether, presumably the bacteriocin contained of a lipid component. It sums likely that L. acidophilus A4 bacteriocin adsorb to a regularly arrayed layer of the cell wall.

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A Study on Improvement of a company's R&D Strategy (기업의 기술개발(R&D)중시 전략에 관한 연구)

  • 구현서
    • Journal of the Korea Society of Computer and Information
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    • v.4 no.2
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    • pp.147-154
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    • 1999
  • Research and Development (R&D) departments concentrate their efforts on one of two key types of research: fundamental research to discover new technology, and product development research to determine ways to use new technology or to improve upon already existing technology. Of these two types of research, the first, fundamental research, does not guarantee that successful products will develop. This type of research generally requires the investment of large sums of money without the surety of financial gain. It can, however, greatly enhance a company's image and profit potential if it can then develop a successful product from the fundamental research their scientists and engineers have done. Also, through this type of research, companies can register patents which can result in income from the sale or license of the patented technology or process to other companies. Companies place themselves at financial risk when they delve into fundamental research. For that reason, most companies concentrate their research funds and efforts on the second type of research, product development. For a product to be considered successful the company must realize some sort of benefit such as profit, increased marketshare, market recognition, or any other company-defined benefits. Both types of research require a company's consistent financial investment and planning. As the world market becomes more competitive, only those companies that can produce a product with good quality, competitive pricing, and in a timely manner will thrive. This thesis focuses on issues for developing a successful product through examining a product life cycle, a product portfolio matrix, and reactive and proactive marketing strategies.

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Segmental Analysis Trial of Volumetric Modulated Arc Therapy for Quality Assurance of Linear Accelerator

  • Rahman, Mohammad Mahfujur;Kim, Chan Hyeong;Huh, Hyun Do;Kim, Seonghoon
    • Progress in Medical Physics
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    • v.30 no.4
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    • pp.128-138
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    • 2019
  • Purpose: Segmental analysis of volumetric modulated arc therapy (VMAT) is not clinically used for compositional error source evaluation. Instead, dose verification is routinely used for plan-specific quality assurance (QA). While this approach identifies the resultant error, it does not specify which machine parameter was responsible for the error. In this research study, we adopted an approach for the segmental analysis of VMAT as a part of machine QA of linear accelerator (LINAC). Methods: Two portal dose QA plans were generated for VMAT QA: a) for full arc and b) for the arc, which was segmented in 12 subsegments. We investigated the multileaf collimator (MLC) position and dosimetric accuracy in the full and segmented arc delivery schemes. A MATLAB program was used to calculate the MLC position error from the data in the dynalog file. The Gamma passing rate (GPR) and the measured to planned dose difference (DD) in each pixel of the electronic portal imaging device was the measurement for dosimetric accuracy. The eclipse treatment planning system and a MATLAB program were used to calculate the dosimetric accuracy. Results: The maximum root-mean-square error of the MLC positions were <1 mm. The GPR was within the range of 98%-99.7% and was similar in both types of VMAT delivery. In general, the DD was <5 calibration units in both full arcs. A similar DD distribution was found for continuous arc and segmented arcs sums. Exceedingly high DD were not observed in any of the arc segment delivery schemes. The LINAC performance was acceptable regarding the execution of the VMAT QA plan. Conclusions: The segmental analysis proposed in this study is expected to be useful for the prediction of the delivery of the VMAT in relation to the gantry angle. We thus recommend the use of segmental analysis of VMAT as part of the regular QA.

Performance of the CDMA Receiver with PN Sequence Orthogonal Reception Process (PN 부호의 직교 수신 방식을 이용한 CDMA 수신기 성능)

  • Hyun, Kwang-Min;Yoon, Dong-Weon;Park, Sang-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.4A
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    • pp.200-207
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    • 2003
  • This paper proposes a CDMA receiver structure with time-shifted m-sequence orthogonal reception process, and analyzes the output SNR performance and the characteristics of the orthogonal receiver. This structure can be simply implemented with the converntional receiver adding an additional integrator path in parallel and an adder sums the conventional path and the new path output signals. The structure provides to reference user signal not only increment of signal component but also perfect orthogonal characteristic, canceling the accumulated cross-correlated value out to zero between the reference user and other user signals. Hence, the proposed structure can be applied for channel impulse response measurement, and used for multi-user interference signal cancellation and channel capacity increment by flexible structural inter-working operation of the added path, connection or disconnection, to conventional receiver structure.

An Empirical Study on the Adoption Intention of Informatization (구조방정식(LISREL)을 이용한 정보화수용의도 모델 실증 분석)

  • 박상규;최순영
    • The Journal of Information Technology
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    • v.5 no.1
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    • pp.13-28
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    • 2002
  • This study examines the relationships between the adoption intention and ill results/"digital divide" of informatization. It is very important to enhance the ability to use the information around the country today. Government invested large sums in informatization. As a result, we became a leading country in the information and communication technologies (ICTs). But the speedy growth in information society enlarges the gab between 'information haves'and 'information have-nots', which results in decreasing the efficiency of informatization. Now, we have to consider the idea of "information welfare policy" to approach the problems of "information poor"which refers to those deprived of opportunities to access ICTS and use of the Internet. This paper shows that we can not reach the information welfare society without the solution of these problems, and which are obstacles to progress in informatization. It is hoped that the results from this study bridge and close so called "Digital Divide" within society and create the impartial information welfare society.e impartial information welfare society.

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Effects of the Nursing Intervention on Mother-Infant Interaction (모-영아 상호작용 증진을 위한 간호중재가 수유시 모-영아 상호작용에 미치는 효과)

  • 김미예
    • Journal of Korean Academy of Nursing
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    • v.29 no.6
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    • pp.1355-1364
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    • 1999
  • Mother and infant relationship has a great influence on child's developments. In this study, nursing intervention to increase maternal sensitivity to the infant's cues was applied to 25 primiparas (Experimental Group). Mother and infant interacations of these primiparas were compared with those of 25 primiparas (Control Group) who did not receive the nursing intervention. Fifty primiparas and infants were recruited from a university hospital, a general hospital, and an OBGY clinic located in Taegu city. Mother and infant interactions were assessed at 6 weeks after birth using videotapes. Feeding situations were videotaped and two trained observers analyzed the tapes. Data were collected from March 23rd to July 27th of 1998. Mother and infant interactions during feeding were assessed by the response rating scale which was modified by the author based on NCAST feeding scale (Barnard, 1978a) and AMIS scale (Price, 1983). The validity of the modified rating scale was verified by faculty members and researchers who previously had research experience in the area. Cronbach's Alpha of the modified scale for this study was .90. The data was analyzed by SAS program, using wilcoxon rank sums test, chi square test, Fisher's exact test, and ANOVA. Findings were as follows: 1. Mothers in the experimental group were more likely to have higher scores in mother and infant interactions during feeding than mothers in the control group. 2. Mothers in the experimental group showed better sensitivity to infant's signals or cues, provided growth fostering, and had higher responsibility to the infant's distress than mothers in the control group. 3. Infants in the experimental group showed higher clarity of cues and responsibility to the mother's behaviors than infants in the control group. 4. Mothers and infants in the experimental group showed higher synchronic responses than mothers and infants in the control group. In conclusion, this study has shown that the applied nursing intervention promoted mother and infant interaction among primiparas. Therefore, this study suggests that the nursing interventions to increase maternal sensitivity to the infant's cues should be broadly applied to primiparas, which can be beneficial to the social, affective, and cognitive developments of their children.

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