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Evaluation of Performance and Construction the New National Test Road Sites of Modified Asphalt (신설국도의 시험시공을 통한 표층용 개질 아스팔트 공용성 평가)

  • Cho, Gyu-Tae
    • International Journal of Highway Engineering
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    • v.4 no.3 s.13
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    • pp.43-49
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    • 2002
  • Asphalt pavements have to perform under the conditions of heavily-loaded vehicles due to the industrialization and large temperature variance between the summer and the winter. Due to these factors, a characteristics change of early permanent deformation becomes a big issue, and to remedy this problem many research to use modified asphalt are being widely conducted. However, most of the modified asphalt is being paved after milling the surface course and applying tackcoating, and it is being used mostly for the repair and maintenance purpose rather than pavement of new national road. The purpose of this investigation is to obtain some fundamental data for the evaluation of the performance and long-term performance of the construction material mixtures by the laboratory test and field experiments. For the field experiment, 200m of two-lanes national road, that is being paved for the new national road under the direction of Pusan Regional Construction Management Office, was paved with SBS PMA and PSMA asphalt mixtures, which are an modified asphalt mixtures used for the surface course, on top of the base course paved with other modified asphalt mixtures. The remaining section of the new national road was paved with dense grade mixture. The laboratory tests assessed and analyzed the mixture characteristics by Marshall's stability test, strength tests and wheel-tracking test. On the basis of the evaluation result of the temperature control and roughness of the newly constructed road at the field experiment site, it is desired to evaluate and identify the most economic modified asphalt mixtures by long-term performance evaluation and LCC(Life Cycle Cost) analysis in order to apply the test result to the design of new road construction in the future.

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Effects of morbidity in Korean peninsula due to sand dust using satellite aerosol observations (위성기상자료를 활용한 황사에 따른 한반도 국민 건강영향평가)

  • Choi, Minyoung;Kim, Hyunglok;Kim, Sangman;Choi, Minha
    • Korean Journal of Remote Sensing
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    • v.32 no.5
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    • pp.499-509
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    • 2016
  • The occurrence of sand dust has been steadily increased since 1990 and the amount of damage was also increased. In most of previous studies, ground based observations were used for sand dust analyses, but its high spatio-temporal variability has not been well understood. In this study, satellite aerosol observations were used to overcome current limitations of the sand dust variability in space and time and to estimate associations with morbidity of respiratory and cardiovascular ailments. In general, high AODs were observed in the west part of the Koran peninsula in spring. The reasonable associations between the morbidity and sand dust were observed from April to July with highest positive correlation (~0.6) at three month lags (lag 3). Based on the results, we found a utility of the satellite aerosol observations for sand dust analyses by considering of morbidity effects. In addition, health effect against the sand dust is proved to be examined and smooth medical supplies and prevention of undesired medical expenses would be possible.

Biochemical Characterization of an Extracellular Protease in Serratia proteamaculans Isolated from a Spider (무당거미에서 분리한 Serratia proteamaculans에서 분비되는 단백질분해효소의 생화학적 특성)

  • Lee Kieun;Kim Chul-Hee;Kwon Hyun-Jung;Kwak Jangyul;Shin Dong-Ha;Park Doo-Sang;Bae Kyung-Sook;Park Ho-Yong
    • Korean Journal of Microbiology
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    • v.40 no.4
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    • pp.269-274
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    • 2004
  • Serratia proteamaculans isolated from the midgut of a spider formed big halos around the bacterial colonies, indicating that the bacterial strain produces an extracellular protease. Activity staining of the extracellular pro­tein fractions using zymogram also demonstrated that the major protein with an estimated molecular mass of 52 kDa contained a high proteolytic activity. The protease was purified to near electrophoretic homogeneity from the culture supernatant after filtration and ion exchange and size exclusion chromatography. The purified enzyme had a relatively high proteolytic activity between pH 6.0 and 10.0 and at broad temperature range. The proteolytic activity of the enzyme was not inhibited by phenylmethylsulfonyl fluoride but strongly inhibited by 1, 10-phenanthroline and EDTA. The activity also was dependent on the presence of $Ca^{++}\;and\;Zn^{++}$ ions. These observations indicate that the enzyme is a metalloprotease.

A Study on Determinants of Commercial Land Values in Gwangju City (광주시 상업지 지가의 형성요인에 관한 연구)

  • Lee, Hyun-Wook
    • Journal of the Korean association of regional geographers
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    • v.2 no.2
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    • pp.159-171
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    • 1996
  • The aim of this study is which factors affect the commercial land values and how they act upon them through distribution of commercial land values by multiple regression analysis in Gwangju city. The major findings of this study are as follows: (1) The changes of commercial land values distribution in $1989{\sim}1996$, We see that the commercial area of higher land values extends following the main arterial road. This is related to urbanization in urban fringe while the decline of commercial land values occurs in city center with long history of commercial region. This is due to unsuitableness in rapid changes of commercial environment because of fragmented lots, old buildings. traffic congestion etc. (2) The regions where commercial land values greatly rose are the west in constructed the new planning city center of Sangmu-dong. and the south west in which is related to the extension of high density apartment and the location of big discount stores. (3) Through the changes in commercial land values distribution map. and road map, topographical map, we know that commercial land values is related to various factors; namely, distance from CBD, convenient traffic, reputation of commercial district, condition of a road, size of supplementary, a degree of commercial land use etc. (4) From the above related factor, six variables are extracted by operational definition. That is the spatial distance from the city center, the walking distance to a stopping place, the road width, the amount of bus traffic, the amount of pedestrian, the number of the shop. (5) Data of seven variables are collected on the highest values point of each Dong. We applicate multiple regression analysis with commercial land values as a dependent variable, extracted six variables as independent variables. (6) As a result of multiple regression on the determinants of commercial land values, the variables which is greatly related to commercial land values are the amount of pedestrain, the spatial distance from city center. We identify that two variables explain variance of the commercial land values by 65%. (7) In order to make clear about not explained 35%. we carry out analysis of residual. In consequence, we see small estimate in downtown area and large estimate in urban fringe. This feature is due to simple core structure of Gwangju city and limits of this regression model.

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Comparison of Occurrences of Coleoptera by Three Sampling Methods in Mt. Yeonyeop Area, Korea (채집법에 따른 연엽산 일대 딱정벌레목의 출현상 비교 분석)

  • Jeong Jong-Kook;Lee Seung-Il;Choi Jae-Seok;Kwon Oh-Kil
    • Korean Journal of Environmental Biology
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    • v.23 no.3 s.59
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    • pp.228-237
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    • 2005
  • To compare the occurrence of Coleoptera by different sampling methods such as light trap, pitfall trap and sweeping, we collected samples every month from April to September,2004 in the Mt. Yeonyeop, Gangwon-do, Korea. According to the sampling methods, the species composition, abundance and dry weight were completely different. We collected 151 species in 35 families (690 individuals) by sweeping method, 148 species in 30 families (689 individuals) by light trap, and 112 species in 18 families (1,674 individuals) by pitfall trap, respectively. The dry weight in collected sample was about 181.46 g in pitfall trap,39.85 g in light trap, and 10.89 g in sweeping method, respectively. Relatively high flight and small-sized beetles such as Coccinellidae, Nitidulidae, Scarabaeidae were collected in light trap. The species diversity was high in July. Unlike the samples collected in light trap, the pitfall trap samples were big-sized saprophagous or carnivorous beetles such as Carabidae, Silphidae, Staphylinidae. The pitfall trap showed relatively the higher number of individual and lower species diversity compared to other methods. The major samples collected by sweeping method were small-sized carnivorous or herbivorous beetles such as Chrysomelidae, Curculionidae, Coccinellidae. The peak of species diversity occurred in May. The similarity was calculated with the Jaccard's index over the light trap-pitfall trap was 0.07, light trap-sweeping was 0.10, and pitfall trap-sweeping was 0.01. Consequently, similarity of sampling methods was relatively low. In conclusion, efficiency of the each sampling methods significantly differed in the species composition of Coleoptera. This study emphasize the necessity of using three sampling methods in the area of diversity research.

Evaluation of Dynamic Modulus based on Aged Asphalt Binder (아스팔트 바인더의 노화특성을 고려한 동탄성계수 평가)

  • Lee, Kwan-Ho;Cho, Kyung-Rae;Lee, Byung-Sik;Song, Yong-Seon
    • Journal of the Korean Society of Hazard Mitigation
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    • v.8 no.3
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    • pp.51-58
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    • 2008
  • Development of a new design guide which is based on empirical-mechanistic concept for pavement design is in action. It is called AASHTO 2002 Design Guide in USA and the KPRP(Korean Pavement Research Project) in Korea. The material characteristic of hot mix asphalt is a key role in the design guide. Therefore it is urgent to get a proper materials database, especially the dynamic modulus of hot mix asphalt. In this research, dynamic modulus test, which is based on aged asphalt binder, has been carried out and proposed the predicted equation of dynamic modulus. Nine different hot mix asphalt with three different asphalt binder have been used for the dynamic modulus test. Short-term aging, which is covers the time for the production of asphalt plant, transportation, lay-down, and compaction, can be simulated at $135^{\circ}C$ with 2 hour curing. Long-term aging has been carried out for a performance period of asphalt pavement. The dynamic modulus of asphalt pavement increases with aging time. As the nominal aggregate size increases, the change of dynamic modulus is not big.

Education for Talent and Aptitude Development and Leisure Satisfaction of Middle School Students (중학생의 특기ㆍ적성 교육 활동 참여 실태와 여가 만족)

  • 김경애;정난희;모은자
    • Journal of Korean Home Economics Education Association
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    • v.15 no.2
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    • pp.1-19
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    • 2003
  • The study has examined the relationship between the middle school students´ after school activities and leisure satisfaction to provide the opportunity of making good use of leisure time and of developing students´ latent talent and aptitude. The research finding are as follows : 1. Based on socio-demographic variables. the female students had more rates of participation in talent and aptitude educational activity than male students. The number of the students from rural areas was much bigger than that of cities such as Gwangju or other big cities in Chonnam. But the students whose parents made a lot of money showed less interest in participating talent and aptitude educational activities. 2. Based on the research of socio-demographic variables, students from counties or smaller areas showed more satisfaction than Gwangju in leisure satisfaction among the six subordinate categories. 7th graders were more satisfied in educational and environmental leisure activities than 8th or 9th graders. Moreover. as the family income is higher and as the father´s educational level is higher. satisfaction rate from leisure activities came out to be higher 3. In regard to satisfaction they get from their leisure activities, it was comparatively high when they had the activities voluntarily as their hobbies or for fun. Some students regarded it as their chances for the next step and they were really satisfied, too. And also the period of time was one of the factors that affected students´ satisfaction. They were satisfied enough when they had the activities less than four month in a year The students who had strong concentration and great enthusiasm showed high leisure satisfaction in all areas except for the environmental one.

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A Study on Characteristics of Eco-friendly Behaviors using Big Data: Focusing on the Customer Sales Data of Green Card (빅 데이터를 활용한 친환경행동 특성에 관한 연구: 대용량 그린카드 거래데이터를 중심으로)

  • Lim, Mi Sun;Kim, Jinhwa;Byeon, Hyeonsu
    • Journal of Digital Convergence
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    • v.14 no.1
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    • pp.151-161
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    • 2016
  • As part of a policy to address climate change and pollution problem, the government introduced a green credit card scheme in order to motivate pro-environmental behaviors in July 2011. It is important to present the specific ways to facilitate pro-environmental behaviors using the consumer behavior pattern data. This study was a result of data from total fifty seven thousands customer purchasing history data of green credit card to be created for the 3 months from January to March 2015. As the analysis process is put in to operation the analysis of the purchasing customer's profile firstly, and the second come into association analysis to consider the buying associations for green products purchasing networks, the third estimate the useful parameters to affect the customer's pro-environmental behavior and customer characteristics. It shows that royal customers are from 30 to 40 years old and their incomes are from 30 million won to 40 million won. Especially, they live in Daegu, Gyeonggi, and Seoul.

A clinical study about painful manifestation on lumbar with regard to movement change of trunk (체간의 움직임 변화에 따른 요추부 근육의 통증 발현에 대한 임상적 고찰)

  • Kim, Sung-Ryul;Lee, Suk-Min;Song, Chang-Ho
    • The Journal of Korean Physical Therapy
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    • v.16 no.3
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    • pp.86-96
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    • 2004
  • A clinical study about painful manifestation on lumbar with regard to movement change of trunk The purpose of this study is to present the basis of low back pain therapy which is close examined of back muscle that is the main reason for that case of back pain when trunk rotation, flexion and extension. Therefore this study, which is based on literature review and clinical experience, has tried to figure out that back pain which is considered to be significant for the most increasing time, posture, motion, painful area, involved muscle have any influence on trunk rotation, flexion and extension This study has done with the patients in oriental rehabilitation clinic, K-oriental hospital, from Jan, 2003 to Dec, 2003. Total cases were 145(male:$39\%$-52 patients, female:$64.1\%$-93 patients) those who complained lumbosacral pain with radiating that makes patient unable to bending or extending the trunk. And they were surveyed retrospect way, checking the medical record and that of therapist. Results are as followings. 1. For sprain patient, $34.5\%$ complained pain on extension, and among them, the most remarkably, patients who did right rotation extension pattern were $20\%$. Herniated disc patient shows greater limit on flexion when trunk moves bending route, but right rotation with extension pattern shows the most limitation on flexion-extension according to the rotation of trunk 2. Cases of morning back pain($60.5\%$) showed high value on right rotation extension pattern($18.6\%$), right rotation flexion pattern($16.3\%$) but did not show big difference on left flexion and extension pattern 3. Patients those who complain pain on sitting position showed highest value each left, right $14.6\%$ of left and right rotation extension pattern 4. Among extension painful patient, there showed highest value of each $32.5\%$ on right rotation extension pattern, and $20.0\%$ on right rotation flexion pattern. 5. Tenderness distribution of quadratus lumborum showed $34.5\%$ on right rotation extension pattern, $20.7\%$ on left rotation extension pattern, and that of iliopsoas muscle at right rotation flexion pattern showed right muscle $20.0\%$, left $50.0\%$ Derived from the results of survey above, for sprain and HIVD patient showed greatest pain on right rotation pattern, for pain plus patient on right rotation extension among those who has extreme pain on sitting in the morning described tenderness on right quadratus lumborum, and those who complain pain on left rotation extension described tenderness on left lumborum the most Decisively, it is possible to figure out the problem muscle that involved when I found the time, position, motion that aggravating and painful area. Therefore this study would be expected to be able to be a useful clinical materials on diagnosis and therapy of low back pain.

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A Study on the Application of Reaction Time and Detailed Security Response (신체반응시간과 근접경호 대응논리 적용에 관한 연구)

  • Lee, Choong-Soo
    • Korean Security Journal
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    • no.15
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    • pp.303-316
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    • 2008
  • One of important protecting skill is securing the minimum safe distance from potential hazard to protect protectee in the emergency situation, that is basic thing for the detailed security in relation to the walking formation and the distance between protectee and crowed. This thesis is to provide the idea on the scientific countermeasure in the gun attack situation, by presenting logic on the reaction time and it's moving distance, on the safe distance between protectee and crowed. Handball goal keeper's reaction time of 0.33seconds is applied, because handball goal keeper's reaction style is very similar to security agent's reaction style. And 4m/sec of record is applied, that is average speed of 'go and return type run of 40m' to calculate it's moving distance. Several researches show that reaction time could be improved by continuing training, similarly security agents could improve their reaction time, providing better reaction skill. The important thing is that it make big difference in the protecting result, although the shortening of reaction time is too slight. Securing safe distance between protectee and crowed and the distance between protectee and security agent could provide effective reaction environment with 'natural protective wall effect' by security agent

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