• Title/Summary/Keyword: common source

Search Result 1,029, Processing Time 0.034 seconds

The Hydrochemical and Stable Isotope Characteristics of Shallow Groundwater Near the Gwangju Stream (광주천 인근 천부 지하수의 수리화학 및 안정동위원소 특성)

  • Yoon, Wook;Ji, Se-Jung;So, Chil-Sub
    • Economic and Environmental Geology
    • /
    • v.36 no.6
    • /
    • pp.441-455
    • /
    • 2003
  • The most common water types are found to be Ca-$HCO_3$, Ca-Na-$HCO_3$ and Ca-Na-$HCO_3$-Cl in Gwangju groundwater. Groundwater near the Gwangju stream are characterized Ca-Cl water type, with over 50 mg/L of C1- and 400 ${\mu}$S/cm of EC. The systematic variation of $Cl^-$, $HCO_3^-$,- EC and ${\gamma}^{18}O$ values in groundwater with distance away from drainages is caused by streamwater infiltration. Stable isotope data indicate that ${\gamma}$D and ${\gamma}^{18}O$ values of groundwaters near drainages were enriched by evaporation effect, showing a equation of ${\gamma}$D=7. 1${\times}{\gamma}^{18}O$-1. ${\gamma}^{18}O$ values over -6${\textperthansand}$ are anomalous in the unconfined groundwater zones, which are influenced by the local surface water enriched in $^{18}O$ composition. Groundwater in highland shows remarkably light ${\gamma}^{18}O$ values below -8$\textperthousand$. The infiltration of streamwater is dominant in unconfined alluvium aquifer near drainages. ${\gamma}^{13}$CDIC values (-17.6∼-15.2$\textperthousand$) of groundwaters near drainages revealed that dissolved inorganic carbon (DIC) is predominantly originated from natural soil-derived $CO_2$. ${\gamma}^{15}N$ and ${\gamma}^{18}O$ values of nitrate are 0∼17.0${\textperthansand}$ and 6.6∼17.4${\textperthansand}$, respectively. Relationship between ${\gamma}^{15}N$ and ${\gamma}^{18}O$ shows a systematic isotopic fractionation caused by denitrification of 40∼60%, suggesting that the major source of groundwater nitrate originated from nitrate of soils, and mixing nitrate of soil and sewage or manure.

Elucidation of Dishes High in N-Nitrosamines Using Total Diet Study Data (총식이조사 자료를 이용한 음식별 니트로사민 함량 분포 규명)

  • Choi, Seul Ki;Lee, Youngwon;Seo, Jung-eun;Park, Jong-eun;Lee, Jee-yeon;Kwon, Hoonjeong
    • Journal of Food Hygiene and Safety
    • /
    • v.33 no.5
    • /
    • pp.361-368
    • /
    • 2018
  • N-nitrosamines are probable or possible human carcinogens, which are produced by the reaction between secondary amines and nitrogen oxide in the acidic environment or by heating. Common risk assessment procedure involves the comparison between exposures expressed in the unit, mg/kg body weight/day and the Health-Based Reference dose expressed in the same unit. This procedure is suitable for the policy decision-making and is considered as inappropriate for the consumers to get information about their dietary decision-making. Therefore, the distributions of NDMA (N-nitrosodimethylamine), NDBA (N-nitrosodibutylamine), the six N-nitrosamines (NDMA, NDBA, NDEA (N-nitrosodiethylamine), NPYR (N-nitrosopyrrolidine), NPIP (N-nitrosopiperidine), and NMOR (N-nitrosomorpholine) in the menus grouped based on the presence of main ingredients and cooking methods were analyzed to generate consumer-friendly information regarding food contaminants. Recipes and intakes were taken from 2014 to 2016 KNHANES (The Korean National Health and Nutrition Examination Survey) and only the data from ages of 7 years or older were used. The contamination data were collected from the 2014~2016 Total Diet Study and all the analysis were performed using R software. Rockfish, eel, anchovy broth and pollock were mainly exposed to N-nitrosamines. In terms of cooking methods, soups and stews appeared to contain the highest amount of N-nitrosamines. Cereals, fruits, and dairy products in the ingredient categories, and rice dishes and rice combined with others in recipe categories had the lowest level exposure to N-nitrosamines. In case of N-nitrosamines, unlike other cooking related food contaminants, boiled dishes such as soups and stews and dishes mainly consisting of fishes and shellfishes had highest level of exposure, showing a large discrepancy with the previous thought of processed meat is the main source of N-nitrosamines.

A Study on Efficiency of Water Purification of Korean Village Bangjuk[dike] as a Means of Ecological Watershed Management (생태적 유역관리 도구로써 마을방죽의 수질정화 효율성 고찰)

  • An, Byung-Chul
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.30 no.2
    • /
    • pp.90-100
    • /
    • 2012
  • This study centering on 10 village - Bangjuks analyzed multifunctionality value of village Bangjuks which have been main water treatment system in Korean traditional villages. On the basis of understanding the structure and character of components such as the well, common spring, village waterway and others which making water-flow and consisting of aquatic system in Korean traditional village Bangjuk, the conclusion as the instrumental device of social and ecological role and ecological watershed management, securing the ecosystem soundness of the damaged or deteriated aquatic ecosystem due to the industrialization and urbanization is as below; 1. The traditional village Bangjuk was environmentally friendly hydraulic system which gathers waterways of village into a point including sewage water, retains and flows out to village through agricultural waterway. Through this Bangjuk, they have managed sewage and rainfall runoff flowed out village efficiently. It is not only a detention system of water but a kind of eco-friendly system that flow out water into the rivers after reusing and filtering it. 2. Around five traditional villages and five villages after modernization, this study classified the types of village Bangjuk as three types considering geographic location, size, etc; marsh type of low swamp, high water -low rice field type of natural flow stucture, low water - high rice field type requiring artificial irrigation facility. All the five traditional villages were turned out to be marsh type of low swamp. Geoji, Sanjeri, Ma-am, Yangchon of the agricultural villages were high water-low rice filed type, and Sangchoenri village was classified low water-high rice field type. 3. This study checked up the function of water purification of village Bangjuk. In Wonteo and Geji villages affected by discharge of village sewer and domestic sewage, the efficiency of ammonia nitrogen($NH_3-N$) and total phosphorus(T-P) was 56~95%, which was high. In Sangcheonri and Sanjeri villages strongly affected by stall and farmland, the efficiency of suspended solids(SS) was 70~85%, and that of total nitrogen(T-N) and total phosphorus(T-P) was 5.3~65%. 4. A water purification system can be found out in the system of village Bangjuk that filter out village sewage and rainfall runoff flowed through the settle and filter of pollution source and denitrification of plants. Through this system of village Bangjuk, it must be used as the basic facilities for the ecological watershed management. The sewage management system of village Bangjuk as a eco-filter must be used and studied as an eco-friendly facility for the ecological watershed management around the subwatershed and catchment.

Application Plan of Goods Information in the Public Procurement Service for Enhancing U-City Plans (U-City계획 고도화를 위한 조달청 물품정보 활용 방안 : CCTV 사례를 중심으로)

  • PARK, Jun-Ho;PARK, Jeong-Woo;NAM, Kwang-Woo
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.18 no.3
    • /
    • pp.21-34
    • /
    • 2015
  • In this study, a reference model is constructed that provides architects or designers with sufficient information on the intelligent service facility that is essential for U-City space configuration, and for the support of enhanced design, as well as for planning activities. At the core of the reference model is comprehensive information about the intelligent service facility that plans the content of services, and the latest related information that is regularly updated. A plan is presented to take advantage of the database of list information systems in the Public Procurement Service that handles intelligent service facilities. We suggest a number of improvements by analyzing the current status of, and issues with, the goods information in the Public Procurement Service, and by conducting a simulation for the proper placement of CCTV. As the design of U-City plan has evolved from IT technology-based to smart space-based, reviews of limitations such as the lack of standards, information about the installation, and the placement of the intelligent service facility that provides U-service have been carried out. Due to the absence of relevant legislation and guidelines, however, planning activities, such as the appropriate placement of the intelligent service facility are difficult when considering efficient service provision. In addition, with the lack of information about IT technology and intelligent service facilities that can be provided to U-City planners and designers, there are a number of difficulties when establishing an optimal plan with respect to service level and budget. To solve these problems, this study presents a plan in conjunction with the goods information from the Public Procurement Service. The Public Procurement Service has already built an industry-related database of around 260,000 cases, which has been continually updated. It can be a very useful source of information about the intelligent service facility, the ever-changing U-City industry's core, and the relevant technologies. However, since providing this information is insufficient in the application process and, due to the constraints in the information disclosure process, there have been some issues in its application. Therefore, this study, by presenting an improvement plan for the linkage and application of the goods information in the Public Procurement Service, has significance for the provision of the basic framework for future U-City enhancement plans, and multi-departments' common utilization of the goods information in the Public Procurement Service.

Optimum Conditions for the Removal of External Organic Carbon Sources in a Submerged Denitrification Biofilter (탈질 여과조에서 외부 탄소원 제거를 위한 적정 체류 시간과 외부 탄소원 종류 및 질산염 농도에 대한 외부 탄소원의 적정 비율)

  • 오승용;조재윤;윤길하
    • Journal of Aquaculture
    • /
    • v.12 no.1
    • /
    • pp.47-56
    • /
    • 1999
  • Denitrification by anaerobic bacteria is one of the most common processes of removing nitrate from recirculating aquaculture systems. This process is affected by many factors such as external carbon sources, hydraulic retention time (HRT), and $COD/NO_3-N$ ratio. Although external organic carbon sources are essential for the denitrification process, these also contribute to increase dissolved organic carbon concentration in recirculating aquaculture systems. So these external organic carbons must be removed from the systems. This study was conducted to find out the optimum operating conditions for the removal of external organic carbons in a submerged denitrification biofilter. Combinations of two external carbon sources (glucose and methanol), two HRT (4- and 8-hour), and four different C:N ratios (3, 4, 5, and 6) were used in this experiment. The removal efficiencies of organic carbon sources at 8-hour HRT were always better than those at 4-hour's (P<0.05). Maximum removal efficiencies were achieved when C:N ratio was 5 in both glucose and methanol. The removal efficiencies of methanol were always better than those of glucose. The maximum removal efficiencies of glucose and methanol were 76.5% and 84.0%, respectively and the removal rates were 223.5 $g/m^2/day$ and 247.1$g/m^2/day$. The maximum removal rates of glucose (290.9 $g/m^2/day$) and methanol (355.6 $g/m^2/day$) were achieved at 4-hour HRT and 5 C:N ratio. But the concentrations of SCOD in the effluent of both glucose ($52.5 mg/\ell$) and methanol ($40.9 mg/\ell$) were too high for rearing fish. Therefore, the optimum operating conditions for the removal of external carbon in a submerged denitrification biofilter were 8-hour HRT and 5 C:N ratio. And methanol showed better efficiency as an external carbon sources.

  • PDF

Resolution of Shallow Marine Subsuface Structure Image Associated with Acquisition Parameters of High-resolution Multi-channel Seismic Data (고해상 다중채널 탄성파탐사 자료취득변수에 따른 천부 해저지층영상의 해상도)

  • Lee Ho-Young;Koo Nam-Hyung;Park Keun-Pil;Yoo Dong-Geun;Kang Dong-Hyo;Kim Young-Gun;Seo Gab-Seok;Hwang Kyu-Duk;Kim Jong-Chon;Kim Ji-Soo
    • Geophysics and Geophysical Exploration
    • /
    • v.6 no.3
    • /
    • pp.126-133
    • /
    • 2003
  • High-resolution shallow marine seismic surveys have been carried out for the resources exploration, engineering applications and Quaternary mapping. To improve the resolution of subsurface structure image, multichannel digital technique has been applied. The quality of the image depends on the vertical and horizontal resolution and signal to noise (S/N) ratio which are associated with the data acquisition parameters such as sample interval, common midpoint (CMP) interval and CMP fold. To understand the effect of the acquisition parameters, a test survey was carried out off Yeosu and the acquired data were analyzed. A 30 $in^3$ small air gun was used as a seismic source and 8 channel streamer cable with a 5 m group interval was used as a receiver. The data were digitally recorded with a shot interval of 2 s and sample interval of 0.1 ms. The acquired data were resampled with various sample intervals, CMP intervals and CMP folds. The resampled data were processed, plotted as seismic sections and compared each other. The analysis results show that thin bed structure with ${\~}1m$ thickness and ${\~}6^{\circ}$ slope can be imaged with good resolution and continuity and low noise using the acquisition parameters with a sample interval shorter than 0.2 ms, CMP interval shorter than 2.5 m and CMP fold more than 4. Because seismic resolution is associated with the acquisition parameters, the quality of the subsurface structure can be imaged successfully using suitable and optimum acquisition parameters.

Inhibitory effects of extracts from Smilacina japonica on lipopolysaccharide induced nitric oxide and prostaglandin E2 production in RAW264.7 macrophages (RAW264.7 대식세포에서 풀솜대 추출물의 nitric oxide 및 prostaglandin E2생성 저해효과)

  • Nam, Jung-Hwan;Seo, Jong-Taek;Kim, Yul-Ho;Kim, Ki-Deog;Yoo, Dong-Lim;Lee, Jong-Nam;Hong, Su-Young;Kim, Su-Jeong;Sohn, Hwang-Bae;Kim, Hyun-Sam;Kim, Bo-Sung;Lee, Kyung-Tea;Park, Hee-Jhun
    • Journal of Plant Biotechnology
    • /
    • v.41 no.4
    • /
    • pp.201-205
    • /
    • 2014
  • Smilacina japonica is a localized common rhizomatous flowering plant, This plant is often used in Korean traditional systems of medicine as a remedy for migrain, diplegia, physical impurity, blood circulation, abscess and contusion. Generally drugs that are used for arthritis have antinociceptive and anti-inflammatory properties. However, validity of the anti-inflammatory activity has not been scientifically investigated so far. Therefore, the aim of this study was to investigate the anti-inflammatory potential of S. japonica using the ethanolic extract and its subfractions. To evaluate the anti-inflammatory effects, we examined the inflammatory mediators such as nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) on RAW 264.7 macrophages. Our results indicated that hexane fraction significantly inhibited the LPS induced NO and $PGE_2$ production in the cells. The hexane fractions inhibitory activity for NO tests with $IC_{50}$ values showed in $53.3{\mu}g/ml$ and $PGE_2$ tests with $IC_{50}$ values showed at $32.5{\mu}g/ml$. Theseis result suggest a potential role of hexane fraction from S. japonica as source of anti-inflammatory agent.

Effectiveness of Internet-based Interventions on HbA1c Levels in Adult Patients with Diabetes: A Meta-Analysis of Randomized Controlled Trials (인터넷 기반 중재프로그램을 통한 성인 당뇨 환자의 HbA1c 중재효과: 메타분석)

  • Jung, Chang Suk;Noh, Hyun Jung;Gu, Min Jeong;Kim, Yi Young;Lee, Soon Young
    • Journal of health informatics and statistics
    • /
    • v.43 no.4
    • /
    • pp.307-317
    • /
    • 2018
  • Objectives: This study aimed to verify the effectiveness of Internet-based intervention programs for adults with diabetes by conducting a meta-analysis of studies conducted since 2000. Methods: We conducted a systematic review of research papers published in domestic and overseas journals from January 2000 to December 2015, and selected 9 papers that met the analysis criteria. Data analysis was performed using the open source statistical software R 3.5.0, to analyze the effectiveness of Internet-based interventions on experimental and control groups. Results: The analysis showed that intervention programs for controlling HbA1c levels in adult patients with diabetes most commonly comprised 7 sessions on Internet-based management (77.8%), and the most common frequency of application of intervention programs was 4 session in 6 months (33.4%). The present meta-analysis revealed statistically significant effects of Internet-based intervention activities (SMD = 0.92, 95% CI 0.45-1.40). The analysis of the effect size according to the intervention period showed that the 3-month, 6-month, and 12-month interventions reported in eight studies (89%) had a high effect on the Internet-based intervention group. Conclusions: The results of this study confirm the effectiveness of Internet-based intervention programs for adult patients with diabetes. The need for research on the utilization of Internet-based intervention programs for the steady management of diabetes, a chronic disease; for the development of specific guidelines for intervention activities; and for establishing appropriate protocols are acknowledged.

Developmental Characteristics of Ovary and Egg of Migratory Locust, Locusta migratoria (Orthoptera: Acrididae) (풀무치(Locusta migratoria)의 난소 및 알 발육 특성)

  • Kwak, Kyu-Won;Ko, Hyeon-Jin;Kim, Sun Young;Lee, Kyeong Yong;Yoon, Hyung Joo
    • Korean journal of applied entomology
    • /
    • v.60 no.2
    • /
    • pp.175-183
    • /
    • 2021
  • As a baseline study of (common name) Locusta migratoria (Orthoptera: Acrididae) to utilize as a food source, we investigated the developmental characteristics of ovaries and eggs. Locusta migratoria had a pair of ovaries and more than 90-104 panoistic ovarioles. The ovary length in the adult stage was longer than it is in the 5th nymph stage. The length on the first day of the adult stage was 2.5-fold longer than the first day of 5th instar. The ovary length showed a tendency to increase until the 30th day of the adult phase, but decreased from the 35th day. Ovarioles length was about half of the ovary length, showing a similar tendency to the variation of ovary length. The lengths of the ovaries and the ovarioles increased proportionally to body weight. The matured eggs were identifiable from the 15th day of the adult stage, and the number was the highest on the 30th day at 50.6 individuals. Spermatheca size was also affected by the ovary development. The ovaries of L. migratoria were highly matured until the 30th day of adult stage. Weight and size of eggs increased sharply from the 4th day after egg oviposition and remained from the 7th day after spawning. Based on the above results, we found that the ovary of L. migratoria was most developed on the 30th day of adult phase, and 1st nymph is being hatched on the 10th day of the oviposition.

The Sillok as National Supreme Archives : An archival interpretation (실록(實錄) : 등록(謄錄)의 위계(位階))

  • O, Hang-Nyeong
    • The Korean Journal of Archival Studies
    • /
    • no.3
    • /
    • pp.91-113
    • /
    • 2001
  • History always be re-interpreted as the time flows. 'The Sillok', Which was registered in Memory of World of UNESCO in 1997, is comprehensive documents of the Chosun Dynasty, which had been compiled after kings' death, The Sillok encompasses 473 years of the reign in their 848 volumes(1,893 chapters). It was a history itself and has been main source in studying Korean history. Due to the rise of studies on the Sillok, time has come to explore the nature of the Sillok and to criticize the text, which would be called 'The Sillok-Study'. In this context, this paper examined three concepts that categorize the nature of the Sillok as historical materials ;Is it book or record?; The Sillok in register system in pre-modern society; And the Sillok as the National Archives. Korean historians, including myself, haven't yet examined the question whether the Sillok is the Book or Record in terms of archival science. At first, I regarded it as history book, and with this presupposition, wrote several papers on the characteristics of the Sillok. However, I recognized that the Sillok are close to record rather that history book as I examined the definition of glossary of librarian study, OED (Oxford English Dictionary) and Encyclopedia of Britannica, etc. Definitely, the Sillok was neither compiled and published to be read and sold publicly, nor meant to the works of literature or scholarship. one may say that the court-historians wrote comments on the facts and therefore it was just scholarly work. However, because the court-historians produced their comments on their own businesses, the outcome of 'their scholarly works' were also records conceptually, as were daily court-journalists in Rome. Its publication also had a absolutely different meaning from that of modern society. It was a method to preserve the important national records and distributed each edition of them to plural repositories for its safety and security. How can we explain its book-like shape and the procedure of compilation after a kings' death. The answer is as follows ; In pre-modern society, it was a common record-keeping system in the world to register records materials in order to arrange the materials of different sizes and to store them conveniently. And the lack of scientific preservation or conservation skill also encouraged them to register original records. Actually, the court-historians who participated in the compiling process called themselves "registering officers". On the other hand, similar to social hierarchy, there was a hierarchical system of records, and the Sillok was placed at the top of this hierarchy. In conclusion, the Sillok was a kind of registered records in the middle ages and the supreme records in the records-world. In addition to this we can also conceptualize the Sillok as archives. Through the compiling process, the most important and valuable records were selected to be the parts of Sillok. This process corresponds to the modem records appraisal. In the next step, it was preserved in the Four Archives(史庫) which located at remote site as archives and only accessible by the descendents in the future, who might be the people of the next dynasty. And nobody could access or read the documents at that time except the authorized court-historians who were archivists of the Chosun Dynasty. From this perspective, I conclude that Sillok was the supreme confidential archives in the register system. I work for the Government Archives as a historian and archivist. Whenever I entered the exhibition hall of the Government Archives and Records Service(GARS) and saw the replica of the Archives of Taebeak Mountain built during Chosun period, I always asked to myself a question whether the Sillok can be a symbol of the archival tradition of Korea and the GARS. Now, I can say, 'Yes!' definitely.