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Elemental Composition and Source Identification of PM2.5 in Jeju City (제주시 미세먼지(PM2.5)에 함유된 원소의 조성특성 및 오염원)

  • Lee, Ki-Ho;Hu, Chul-Goo
    • Journal of Environmental Science International
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    • v.27 no.7
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    • pp.543-554
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    • 2018
  • From November 2013 to December 2016, ambient fine particulate matter ($PM_{2.5}$) was sampled in the downtown area of Jeju City, South Korea, which has seen rapid urbanization. The atmospheric concentrations of elements were measured in the $PM_{2.5}$ samples. This study focused on Cd, Cr, Cu, Mn, Ni, Pb, As, Sb, Sn, V, and Zn. The concentrations of Al, Na, K, Fe, Ca, Mg, Sr, and La were also obtained for reference. The objectives of this study were to examine the contributions of these elements to $PM_{2.5}$ concentrations in downtown Jeju City, and to investigate the inter-element relationships and the elemental sources by using enrichment factors and principal components analysis (PCA). A composition analysis showed that the 19 elements constituted 6.65 % of the $PM_{2.5}$ mass, and Na, K, Al, Fe, Ca, Mg, and Zn constituted 98 % of the total ion mass. Seasonal trend analysis for the sampling period indicated that the concentrations of the elements increased from November to April. However, no substantial seasonal variations were found in the concentrations of the elements. The composition ratios of some elements (Cu/Zn, Cu/Cd, Cu/Pb, V/Ni, and V/La) were found to be out of range when compared to the literature from other urban areas. The ratios between the elements and the PCA results showed that local contaminant sources in Jeju City rarely influence the composition of $PM_{2.5}$. This suggests that the major sources of $PM_{2.5}$ in Jeju City may include long-range transport of fine particulate matter produced in other areas.

In vivo Investigation of Anti-diabetic Properties of Ripe Onion Juice in Normal and Streptozotocin-induced Diabetic Rats

  • Lee, Chul-Won;Lee, Hyung-Seok;Cha, Yong-Jun;Joo, Woo-Hong;Kang, Dae-Ook;Moon, Ja-Young
    • Preventive Nutrition and Food Science
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    • v.18 no.3
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    • pp.169-174
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    • 2013
  • The acute and subacute hypoglycemic and antihyperglycemic effects of drinkable ripe onion juice (Commercial product name is "Black Onion Extract") were investigated in normal and streptozotocin-induced diabetic rats. For tests of acute and subacute hypoglycemic effects, ripe onion juice (5 and 15 mL/kg b.w.) was administered by oral gavage to normal Sprague Dawley rats and measurements of fasting glucose levels and oral glucose tolerance tests were performed. Tolbutamide was used as a reference drug at a single oral dose of 250 mg/kg b.w. To test anti-hyperglycemic activity, the ripe onion juice was administered to streptozotocin-induced diabetic rats by oral gavage at single dose of 15 mL/kg b.w. per day for 7 consecutive days. Oral administration of the ripe onion juice at either dosed level of 5 or 15 mL/kg b.w. showed no remarkable acute hypoglycemic effect in normal rats. The two dosed levels caused a relatively small reduction, only 18% and 12% (5 and 15 mL/kg b.w., respectively) decrease in glucose levels at 2 h after glucose loading in normal rats. However, at 3 h after glucose loading, blood glucose levels in the ripe onion juice-dosed rats were decreased to the corresponding blood glucose level in tolbutamide-dosed rats. Although showing weak hypoglycemic potential compared to that of tolbutamide, oral administration of ripe onion juice (15 mL/kg b.w.) for a short period (8 days) resulted in a slight reduction in the blood glucose levels that had elevated in Streptozotocin-induced diabetic rats. In conclusion, these results suggest that the commercial product "Black Onion Extract" may possess antihyperglycemic potential in diabetes.

A Study of Conflict between Monther-in-law and daughter-in-law in the Changing Korean society with Special reference to Pusan Area (변화하는 한국사회에 있어서 고부 갈등에 관한 연구)

  • 고정자
    • Journal of the Korean Home Economics Association
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    • v.26 no.4
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    • pp.129-160
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    • 1988
  • The purpose of the present study is to understand the change in the relation between mother-in-law and daughter-in-law according to the social change in comparison with the survey effects in 1974 (ko Jung-Ja) and 1985 to find out the cause of conflict in both side of power structure and affection structure, indicating behavior, the influences on the relationships among family, possible meditators. this thesis was made by an experimental research. Data were collected from 146 mothers-in-law and 141 daughters-in-law in Pusan. The collected data were analysed by statistical methods such is as follows, 1. cause of conflict In power structure the cause of conflict is, in the case of mother-in-law opinion opposion and shaughty attitude by daughter in-low and, in the case of daughter-in-law, domestic dominance. It is thought that there is a difference of viw\ew between mother-in-law and daughter-in-law about the possesion of economic dominance and many conflicts rises because of economic dominance. but the study in 1985 than 1974 suggests the possibility of conflict meditator because mother-in-law and daughter-in-law do homework dependently in the practice of power. In affection structure, the chief dissatisfaction toward daughter-in-law showes the change in time. In 1974, there was no affection and respect. In 1985, the rate of doing without consultation was high. Also, the lack of communication of mother-in-law and daughter-in-law is the cause of conflict. 2. Indicating behavior the rate of thinking alone if high in both sides. But in the survey of 1985, the covert verbal aggressive action with which mother-in-law appeals to her daughter and daughter-in-law to husband is rising. 3. Influence on the relationship among family by the conflict between mother-in-law and daughter-in-law. the conflict between mother-in-law and daughter-in-law play negative effects on the intimacy and relation between husband and wife. 4. Conflict mediation behavior As compremiser, it is suggested that in the case of daughter-in-law the position and role of husband is important and, in the case of mother-in-law respects mother-in-law, daughter-in-law and gives her the role.

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A Study on Application Boundary of Wireless LAN's Communication for Space Variation (공간변화에 따른 Wireless LAN의 통신 활용 범위에 관한 연구)

  • Cha, Jin-Man;Kang, Min-Soo;Park, Yeoun-Sik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.499-503
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    • 2005
  • The objective of this thesis is to measure the limit of the real space where wireless Local Area Network(LAN) is used, and to apply this result as reference to set up a real Wireless LAN environment. The organized circumference was composed of Wireless LAN based on IEEE 802.11b of the American standard, and the examination is carried out on the campus. On the real condition of office environment and open space, the ratio of available distance to a signal at each distance was measured and this result was studied as data to embody wireless LAN on the campus. The measurement under an indoor environment was executed under circumstance having two wall and open space, however, was executed respectively under three circumstances : Where no obstacle, where one wall exists, and where two or more walls exist.

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A Maximum Likelihood Estimator Based Tracking Algorithm for GNSS Signals

  • Won, Jong-Hoon;Pany, Thomas;Eissfeller, Bernd
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.2
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    • pp.15-22
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    • 2006
  • This paper presents a novel signal tracking algorithm for GNSS receivers using a MLE technique. In order to perform a robust signal tracking in severe signal environments, e.g., high dynamics for navigation vehicles or weak signals for indoor positioning, the MLE based signal tracking approach is adopted in the paper. With assuming white Gaussian additive noise, the cost function of MLE is expanded to the cost function of NLSE. Efficient and practical approach for Doppler frequency tracking by the MLE is derived based on the assumption of code-free signals, i.e., the cost function of the MLE for carrier Doppler tracking is used to derive a discriminator function to create error signals from incoming and reference signals. The use of the MLE method for carrier tracking makes it possible to generalize the MLE equation for arbitrary codes and modulation schemes. This is ideally suited for various GNSS signals with same structure of tracking module. This paper proposes two different types of MLE based tracking method, i.e., an iterative batch processing method and a non-iterative feed-forward processing method. The first method is derived without any limitation on time consumption, while the second method is proposed for a time limited case by using a 1st derivative of cost function, which is proportional to error signal from discriminators of conventional tracking methods. The second method can be implemented by a block diagram approach for tracking carrier phase, Doppler frequency and code phase with assuming no correlation of signal parameters. Finally, a state space form of FLL/PLL/DLL is adopted to the designed MLE based tracking algorithm for reducing noise on the estimated signal parameters.

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A Study on Utilization of Drone for Public Sector by Analysis of Drone Industry (국내외 드론산업 동향 분석을 통한 공공분야에서의 드론 활용방안에 대한 연구)

  • Sim, Seungbae;Kwon, Hunyeong;Jung, Hosang
    • Journal of Information Technology Services
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    • v.15 no.4
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    • pp.25-39
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    • 2016
  • The drone is an unmanned aerial vehicle which has no human pilot. Drones can be classified into military drones, commercial drones, and personal drones by usage. Also, drones can be classified from large-sized to nano-sized drone by size and autonomous, remote controlled drone by control type. Especially, military drones can be classified into low-altitude drones, medium-altitude, and high-altitude drones by altitude. Recently, the drone industry is one of the fast growing industries in the world. As drone technologies have become more advanced and cost-effective, Korean government has set its goal to become a top-level country in drone business. However, the government's strict regulation for drone operations is one of the biggest hurdles for the development of the related technologies in Korea and other countries. For example, critical problems for drone delivery can be classified into technical issues and institutional issues. Technical issues include durability, conditional awareness, grasp and release mechanisms, collision avoidance systems, drone operating system. Institutional issues include pilot and operator licensing, privacy rules, noise guidelines, security rules, education for drone police. This study analyzes the trends of the drone industry from the viewpoint of technology and regulation. Also, we define the business areas of drone utilization. Especially, the drone business types or models for public sector are proposed. Drone services or functions promoting public interests need to be aligned with the business reference model of Korean government. To define ten types of drone uses for public sector, we combine the business types of government with the future uses of drones that are proposed by futurists and business analysts. Future uses of drones can be divided into three sectors or services. First, drone services for public or military sectors include early warning systems, emergency services, news reporting, police drones, library drones, healthcare drones, travel drones. Second, drone services for commercial or industrial services include parcel delivery drones, gaming drones, sporting drones, farming and agriculture drones, ranching drones, robotic arm drones. Third, drone services for household sector include smart home drones.

An Empirical Study on Pricing Model for Software Operation (소프트웨어 운영 대가산정 방식에 대한 실증적 연구)

  • Kim, Heungshik;Kim, Choong Nyoung;Seo, Yongwon
    • Journal of Information Technology Services
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    • v.18 no.4
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    • pp.67-82
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    • 2019
  • The purpose of this study is to improve the calculation method of the software operation pricing proposed by the software business price calculation guide from 'input manpower method' to 'rate calculation method'. The software operation pricing of the input manpower method is not objectively calculated in the domestic IT outsourcing situation where the statistical data based on the activity based estimating is insufficient and it is decided by agreement between the owner and the client. In addition, there was no standard for adjusting the productivity according to the characteristics of the operation service. In order to improve this, an operational correction factor item that can affect the software operation productivity was selected based on foreign and domestic standards, and it was confirmed through the first questionnaire to IT operation managers. In order to determine the level of difficulty of the fixed operational correction factors, the operational correction factor using AHP technique was confirmed through a second questionnaire for pairwise comparison. The operational difficulty calculation table was developed with reference to COCOMO and ITIL standards. Finally, we propose a new pricing scheme that reflects the operating rate. Regression analysis was carried out by collecting the data of the domestic public institutions on the estimated cost and the actual cost calculated from the new rate method software operation pricing. The results of the regression analysis show that the estimated cost and the actual cost are related to each other. Mean magnitude of relative error(MMRE) and PRED[25] analysis were added for accuracy analysis. MMRE and PRED also showed satisfactory results, confirming the possibility of replacing the rate method software operation pricing.

Noise Removal and Edge Detection of Image by Image Structure Understanding (화상 구조 파악에 의한 화상의 잡음 제거 및 경계선 추출)

  • Cho, Dong-Uk
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.7
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    • pp.1865-1872
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    • 1997
  • This paper proposes not only the thresholding problem which has been one of the major problems in the pre-existing edge detection method but also the removal of blurring effect occurred at the edge regions due to the smoothing process. The structure of a given image is assigned as one of the three predefined image structure classes by evaluating its toll membership value to each reference structure class:The structure of an image belongs to the structure class which has the least cost value with the image. Upon the structure class assigned, noise removal and edge extraction precesses are performed, e.g., the smoothing algorithm is applied to the image if its structure belongs to the pure noise region class; edge extraction while removing the noise is performed simultaneously if the edge structure class. The proposed method shows that preventing the blurring effect can be usually seen in the edge images and extracting the edges with no using thresholding value by the experiments.

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Effect of Image quality and Radiation Dose using Iterative Reconstruction in Adult and Pediatric CT: A Phantom Study (성인과 소아 CT 촬영시 IR 적용에 따른 영상화질 및 선량에 미치는 영향)

  • Ju, A-ran;Jo, Jung-Hyun;Oh, Young-Kyu;Kim, Kyoung-Ki;Lee, Soo-Been;Jeon, Pil-Hyun;Kim, Daehong
    • The Korean Journal of Food & Health Convergence
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    • v.4 no.1
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    • pp.23-31
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    • 2018
  • The main issue of CT is radiation dose reduction to patient. The purpose of this study was to estimate the image quality and dose by iterative reconstruction (IR) for adults and pediatrics. Adult and pediatric images of phantom were obtained with 120 and 140 kV, respectively, in accordance with radiation dose in terms of volume CT dose index ($CTDI_{vol}$): 10, 15, 20, 25, 30, 35 mGy. Then, the adult and the pediatric images are reconstructed by filtered-backprojection (FBP) and iterative reconstruction (IR). The images were analyzed by signal-to-noise ratio (SNR). SNR is improved when IR and 140 kV are applied to acquire adult and pediatric images. In the adult abdomen, according to diagnostic reference level, the SNR values of bone were increased about 27.84 % and 27.77 % at 120 kV and 140 kV, and the tissue's SNR values of the IR were increased about 29.84 % and 33.46 % 120 and 140 kV, respectively. Dose is reduced to 40% in adults abdomen images when using IR reconstruction. In pediatric images, the bone's SNR were also increased about 17.70% and 18.17 % at 120 kV and 140 kV. The tissue's SNR were increased about 26.73 % and 26.15 % at 120 kV and 140 kV. Radiation dose is reduced from 30% to 50% for bone and tissue images. In the case of examinations for adult and pediatric CT, IR technique reduces radiation dose to patient, and it could be applied to adult and pediatric imaging.

Statatistical Analysis of Three Sequence-Three Periods Bioequivalence Study : Application to Bioequivalence Test of Ondansetron Formulations ($3{\times}3$ 라틴 방격법 모델에 따른 생물학적 동등성 시험의 통계 해석 : 온단세트론 제제에 대한 적용 예)

  • Lee, Young-Joo;Lee, Myung-Gull;Chung, Suk-Jae;Lee, Min-Hwa;Shim, Chang-Koo
    • Journal of Pharmaceutical Investigation
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    • v.28 no.1
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    • pp.35-42
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    • 1998
  • A $3{\times}3$ Latin square crossover study for the bioequivalence of three ondansetron formulations was conducted. Test products were $Vominon^{\circledR}$ 8 mg and $Vominon^{\circledR}$ 4 mg tablets and reference product was $Zofran^{\circledR}$ tablet. Twenty one healthy Korean male subjects received each formulation at the ondansetron dose of 8 mg and plasma concentrations of ondansetron were monitored by HPLC for over a period of 12 hr after the oral administration. Statistical procedure for bioequivalence evaluation of AUC {e.g., analysis of variance (ANOVA), multiple comparison and confidence intervals} was carried out. There were no significant differences in AUC among the formulations. The confidence intervals for the AUC of $Vominon^{\circledR}$ 8 mg and $Vominon^{\circledR}$ 4 mg were between -0.24 and 15.54% and between -2.41 and 13.36% respectively, within a range that proposed by the Korea Food and Drug Administration Guidelines for Bioequivalence. These statistical procedure could be standardized and generally applicable for the assessment of bioequivalence for multiple (more than two) formulations.

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