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Dispersion of Air Pollutants from Ship Based Sources in Incheon Port (인천항의 선박오염원에서 배출된 대기오염물질의 확산)

  • Kim, Kwang-Ho;Kwon, Byung Hyuk;Kim, Min-Seong;Lee, Don-Chool
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.5
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    • pp.488-496
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    • 2017
  • Emissions of pollutants from ship-based sources are controlled by the International Maritime Organization (IMO). Since pollutants emitted from ship may be dispersed to the land, controlling emissions from ships is necessary for efficient air quality management in Incheon, where exposure to ship-based pollution is frequent. It has been noted that the ratios of air pollutant emissions from coastal areas to inland areas are about 14% for NOx and 10% for SOx. The air quality of coastal urban areas is influenced by the number of ships present and the dispersion pattern of the pollutants released depending on the local circulation system. In this study, the dispersion of pollutants from ship-based sources was analyzed using the numerical California Puff Model (CALPUFF) based on a meteorological field established using the Weather Research and Forecasting Model (WRF). Air pollutant dispersion modeling around coastal urban regions such as Incheon should consider point and line sources emitted from both anchored and running ships, respectively. The total average NOx emissions from 82-84 ships were 6.2 g/s and 6.8 g/s, entering and leaving, respectively. The total average SOx emissions from 82-84 ships, entering and leaving, were 3.6 g/s and 5.1 g/s, respectively. The total average emissions for NOx and SOx from anchored ships were 0.77 g/s and 1.93 g/s, respectively. Due to the influence of breezes from over land, the transport of pollutants from Incheon Port to inland areas was suppressed, and the concentration of NOx and SOx inland were temporarily reduced. NOx and SOx were diffused inland by the sea breeze, and the concentration of NOx and SOx gradually increased inland. The concentration of pollutants in the area adjacent to Incheon Port was more influenced by anchored ship in the port than sea breezes. We expect this study to be useful for setting emission standards and devising air quality policies in coastal urban regions.

The Research of Storage Capacity & Sedimentation of Reservoirs in HONAM Province (호남지방에 저수지의 매몰상황과 저수량에 관한 조사연구(농학계))

  • 이창구
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.13 no.2
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    • pp.2262-2275
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    • 1971
  • Fourteenes rervoirs maintained by the local land improvement associations in the province of Chullabuk-Do and 20 reservoir maintained by thos in the province of Chullanam-Do, were surveyed in connection with a correction between storage capacity and sediment deposit. In addition to this survey, 3,347 of small reservoir, that lie scattered around in the above-mentioned two provinces were investigated by using existing two provinces were investigated by using existing records pertaining to storage capacity in the office of City and country, respectively. According to this investigation the following comclusions are derived. 1. A sediment deposition rate is high, being about $10.63m^3/ha$ of drainage area, and resulting in the average decreasc of storage capaity by 27.5%. This high rate of deposition coule be mainly attributed to the serve denudation of forests due to disorderly cuttings of trees. Easpecially, in small reservoir, an original average design storage depth of 197mm in irrigation water depth is decreased to about 140mm. 2. An average unit storage depth of 325.6mm as the time of initial construction is decreased to 226mm at present. This phenomena causes a greater shortage irrigation water, since it was assumed that original storage quantity was already in short. 3. Generally speaking, seepage rates through dam abutment intakepipe, etc, are high due to insufficient maintenance and management of reservoir. 4. It is recommended that sediment deposit should be dredged when a reservoir is dry in drought. 5. Farmers usually waste excessive irrigation water. 6. Water saving methods should be practiced by applying only necessary water for growing stage of rice. 7. In are as where water defficiency for irrigation is severe, a soil moisture content should be kept at about 70% by applying water once in several days. 8. Tube wells should be provided so as to exploit ground water and subsurface current below stream bed as much as possible. 9. If an intake weir was constructed, a water collection well should be built for the use in drought. 10. Water conservation should be forced by converting devastated forests contained in the drainage area of reservoir to protected forests so as to take priority of yrefor estation, gully control, the prohibition of disorderly cutting of trees, etc. 11. Collective rice nurseries should be adopted, and it should be recommended that irrigation water for rice nurseries is supplied by farmer themselves. 12. Sediment desposit in reservoir should be thoroughly dreged so as to secure a original design storage capacity. 13. The structure of overflow weir should be automatic so as to freely control flood level and not to increase dam height.

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Lead Pollution and Lead Poisoning among Children in China

  • Zheng, Yuxin
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2003.06a
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    • pp.24-25
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    • 2003
  • Lead is ubiquitous in the human environment as a result of industrialization. China's rapid industrialization and traffic growth have increased the potential for lead emissions. Lead poisoning in children is one of the most common public health problems today, and it is entirely preventable. Children are more vulnerable to lead pollution and lead in their bodies can affect their nervous, circulatory, and digestive systems. Children are exposed to lead from different sources (such as paint, gasoline, and solder) and through different pathways (such as air, food, water, dust, and soil). Although all children are exposed to some lead from food, air, dust, and soil, some children are exposed to high dose sources of lead. Significant sources of lead for China's children include industrial emissions (often close to housing and schools), leaded gasoline, and occupational exposure that occurs when parents wear lead-contaminated clothing home from work, burning of coal for home heat and cooking, contaminated food, and some traditional medicines. To assess the blood lead level in children in China, a large-scale study was conducted in 19 cities among 9 provinces during 1997 to 2000. There were 6502 children, aged 3-5 years, were recruited in the study The result indicates that the mean blood lead level was 8.83ug/dl 3-5 year old living in city area. The mean blood lead level of boys was higher than that of girls (9.1l ug/dl vs 8.73ug/dl). Almost 30 percent childrens blood lead level exceeded 10ug/dl. The average blood lead level was higher than that of in 1985 (8.83ug/dl vs 8.lug/dl). An epidemiological study was carried on the children living around the cottage industries recycling the lead from battery. Nine hundreds fifty nine children, aged 5-12 years, living in lead polluted villages where the lead smelters located near the residential area and 207 control children live in unpolluted area were recruited in the study. The lead levels in air, soil, drinking water and crops were measured. The blood lead and ZnPP level were tested for all subjects. The results show that the local environment was polluted. The lead levels both in the air and crops were much higher than that of in control area. In the polluted area, the average blood level was 49.6ug/dl (rang 19.5-89.3ug/dl). Whereas, in the unpolluted area, the average blood level was 12.4ug/dl (rang 4.6-24.8ug/dl). This study indicates that in some countryside area, some cottage industries induce seriously lead pollution and cause children health problem. For the introducing of unleaded gasoline in some large cities, such as Beijing and Shanghai, the blood lead level showed a declined trend since 1997. By 2000, the use of leaded gasoline in motor vehicles has been prohibited in China. The most recent data available show that levels of lead in blood among children in Shanghai decreased from 8.3ug/dl in 1997 to 7.6ug/dl in 1999. The prevalence rate of children lead poisoning (blood lead >10ug/dl) was also decreased from 37.8% to 24.8%. In children living in downtown area, the blood lead level reduced dramatically. To explore the relationship between gene polymorphisms and individual susceptibility of lead poisoning, a molecular epidemiological study was conducted among children living in lead polluted environment. The result showed that the subjects with ALAD2 allele has higher ZPP level, and the subjects with VDR B allele has larger head circumference than only with b allele. In the present study, we demonstrated that ALAD genotypes modify lead effects on heme metabolism and VDR gene variants influence the skull development in highly exposed children. The polymorphism of ALAD and VDR genes might be the molecular inherited factor modifying the susceptibility of lead poisoning. Recently, Chinese government pays more attention to lead pollution and lead poisoning in children problem. The leaded gasoline was prohibited used in motor vehicles since 2000. The government has decided to have a clampdown on the high-polluted lead smelters for recycling the lead from battery in countryside. It is hopeful that the risk of lead poisoning in children will be decreased in the further

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A Study on Radiation Safety Management by Dental Hygienist (치과위생사의 방사선 안전관리에 대한 조사 연구)

  • Kang, Eun-Ju;Lee, Kyung-Hee;Kim, Young-Im
    • Journal of dental hygiene science
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    • v.5 no.3
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    • pp.105-112
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    • 2005
  • In spite of relatively low level of radiation dose used at dental clinics, long term exposure may be harmful, so radiation workers at dental clinics must be well aware of its danger. This study was to analyze the factors to have an influence on safety management behavior in the radiography chamber by understanding the relationship among the knowledge, attitudes and behavior in regard with radiation safety management by dental hygienists in order to take preventive measures for dental hygienists and suggest ideas to develop radiation safety training programs. For this, we contacted dental hygienists working at the local dental clinics for 4 months from December of 2003 to march of 2004 and obtained the following findings. 1. Concering the knowledge level of radiation safety management, $8.59{\pm}2.36$ was average score with the highest of 13 and the lowest of 3 from 15-scale test. In addition, knowledge level of radiation safety management by general characteristics showed statistically significant difference according to working experience (p < 0.001), marital status (p < 0.001), attendance rate of radiation safety management training program (p < 0.001), and type of clinic (p < 0.001). 2. Concering the attitude level of radiation safety management, $4.08{\pm}0.50$ is average score with the highest of $4.31{\pm}0.73$ and the lowest of $3.82{\pm}0.89$ by item from 5-scale test. Besides, attitude level of radiation safety management by general characteristics showed statistically significant difference according to age (p < 0.001), working experience (p < 0.05), attendance rate of radiation safety management training program (p < 0.01), and type of clinic (p < 0.001). 3. Concering the behavior level of radiation safety management, $2.89{\pm}0.77$ is average score from 5-scale test, which was relatively low in comparison with the level of attitude and the highest score was $3.82{\pm}0.94$ and the lowest $2.37{\pm}1.04$ by item. Behavior level of radiation safety management by general characteristics showed statistically significant difference according to working experience (p < 0.001) and type of clinic (p < 0.001). 4. From the survey of relationship among knowledge, attitude and behavior of radiation safety management was, we found that the higher the knowledge level of radiation safety management, the higher the level of attitude and behavior, and the higher the attitude level was, the higher the level of behavior.

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Contamination Assessment of Water Quality and Stream Sediments Affected by Mine Drainage in the Sambo Mine Creek (삼보광산 수계 하천수질 및 퇴적토의 오염도 평가)

  • Jung, Goo-Bok;Kwon, Soon-Ik;Hong, Sung-Chang;Kim, Min-Kyeong;Chae, Mi-Jin;Kim, Won-Il;Lee, Jong-Sik;Kang, Kee-Kyung
    • Korean Journal of Environmental Agriculture
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    • v.31 no.2
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    • pp.122-128
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    • 2012
  • BACKGROUND: Mine drainage from metal mining districts is a well-recognized source of environmental contamination. Oxidation of metal sulfides in mines, mine dumps and tailing impoundments produces acidic, metal-rich waters that can contaminate the local surface water and soil. METHODS AND RESULTS: This experiment was carried out to investigate the pollution assessment of heavy metal on the water quality of mine drainage, paddy soils and sediment in lower watershed affected by mine drainage of the Sambo mine. The average concentrations of dissolved Cd (0.018~0.035 mg/L) in mine drainage discharged from the main waste rock dumps(WRD) was higher than the water quality standards (0.01 mg/L) for agricultural water in Korea. Also, the average concentrations of dissolved Zn, Fe and Mn were higher than those of recommended maximum concentrations (Zn 2.0, Fe 5.0, Mn 0.2 mg/L) of trace metal in irrigation water proposed by FAO (1994). The average contents of Pb and Zn in paddy soils was higher than those of standard level for soil contamination(Pb 200, Zn 300 mg/kg) in agricultural soil by Soil Environmental Conservation Act in Korea. Also, the concentrations of Cd, Pb and Zn in sediment were higher than those of standard level for soil contamination (Cd 10, Pb 400, Zn 600 mg/L) in waterway soil by Soil Environmental Conservation Act in Korea. The enrichment factor (EFc) of heavy metals in stream sediments were in the order as Cd>Pb>Zn> As>Cu>Cr>Ni. Also, the geoaccumulation index (Igeo) of heavy metals in stream sediments were in the order as Zn>Cd>Pb>Cu>As>Cr>Ni, specially, the geoaccumulation index (Igeo) of Zn (Igeo 3.1~6.2) were relatively higher than that of other metals in sediment. CONCLUSION(s): The results indicate that stream water and sediment were affected by mine drainage discharged from the Sambo mine at least to a distance of 1 km downstream (SN-1, SN-2) of the mine water discharge point.

Teachers' Importance Perception of the Contents in Housing Unit of Middle School Technology and Home Economics Subject (중학교 기술 가정 교과의 주생활단원 내용에 대한 교사의 중요도 인식)

  • Jun, Kyung-Sook
    • Journal of Korean Home Economics Education Association
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    • v.20 no.4
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    • pp.223-237
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    • 2008
  • The purpose of this research was to provide the information needed for improving the contents in housing unit of middle school technology and home economic textbook. For this purpose, a survey questionnaire was developed to examine teachers' importance perception of 48 contents in housing unit. A direct survey and an e-mail survey were used to collect data from teachers, and a total number of 233 data were analyzed. Conclusions were summarized as following: 1. Among the 48 contents in housing unit, the average score of teachers' importance perception of the 18 contents on 'interior environment and equipments' was 3.94; the average score of teachers' importance perception of the 15 contents on 'living space plan and use' was 3.78; and the average score of teachers'importance perception of the 15 content on 'housing maintenance and repair' was 3.42. Therefore, the 15 contents on 'housing maintenance and repair' must be revised. 2. Teachers' importance perception of 25 contents, among the 48 contents in housing unit, were significantly differentiated by gender, age, teaching experience, scholastic attainment, subject in charge(technology, home economics, technology and home economics), school type(boys' middle school, girls' middle school, coeducation), and region(city, county). Therefore, the 25 contents, of which importance perception were influenced by teachers' characteristics, must be revised in order to maintain the consistent importance perception. Suggestions were that the team teaching of technology and home economic textbook was more recommendable; that the local situations must be considered in the contents of housing unit and; that the contents of housing unit must be segmented into a minimum unit for the accurate evaluation.

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Ultrasound-Guided Axillary Brachial Plexus Block, Performed by Orthopedic Surgeons (정형외과 의사가 시행한 초음파 유도 액와 상완 신경총 차단술)

  • Kim, Cheol-U;Lee, Chul-Hyung;Yoon, Ja-Yeong;Rhee, Seung-Koo
    • Journal of the Korean Orthopaedic Association
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    • v.53 no.6
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    • pp.513-521
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    • 2018
  • Purpose: The purpose of this study was to assess the effectiveness and complications of an ultrasound-guided axillary brachial plexus block performed by orthopedic surgeons. Materials and Methods: From March to May 2017, an ultrasound-guided axillary brachial plexus block was performed on a total of 103 cases of surgery. A VF13-5 transducer from Siemens Acuson X300 was used. The surgical site was included in the range of the anatomic sensory distribution of the blocked nerve, except for the case where an operation time of more than 2 hours was expected due to multiple injuries and the operation of the upper arm. The procedure was performed by 2 orthopedic surgeons in the same method using 50 ml of solution (20 ml of lidocaine HCl in 2%, 20 ml of ropivacaine in 0.75%, 10 ml of normal saline in 0.9%). The success rate of anesthesia induction during surgery, anesthetic induction time, anatomical range of operation, duration of postoperative analgesia and complications were investigated. Results: The results from the 2 practices were similar. The anesthesia was successful in 100 out of 103 patients (97.1%). In these patients, the average needling time was 5.5 minutes (2.5-13.2 minutes), the average induction time to complete anesthesia was 18.4 minutes (5-40 minutes), and the average duration of postoperative analgesia was 402.8 minutes (141-540 minutes). The post-anesthesia immediate complications were dizziness in 1 case, nausea and vomiting in 4 cases, and peri-oral numbness in 2 cases, but surgery was performed without problems. All these 7 cases with complications recovered on the same day. A total of 3 cases failed with anesthesia, and they were treated by an injection with local anesthesia in the operation room in 2 cases and switched to general anesthesia in 1 case. Conclusion: An ultrasound-guided axillary brachial plexus block, which was performed by orthopedic surgeons allows anesthesia in a brief period and the high success rates of anesthesia for certain surgeries of the elbow and surgeries on forearm, wrist and hand. Therefore, it can reduce the waiting time to the operating room. This technique is a relatively safe procedure and dose selective anesthesia is possible.

Evaluation of External Quality of Polished Barley (시판 소포장 보리쌀의 품위 평가)

  • Bae, Sook-Hyun;Kim, Hong-Sig;Jong, Seung-Keun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.54 no.1
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    • pp.124-133
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    • 2009
  • Demand for the high quality barley with fibroid material and functional substances has been increasing in recent although the amount of barley consumption decreased drastically during the last two decades. But the limited information on quality of barley makes consumers hard when they purchase barley for their own consumption. Therefore, 51 brand barley, .i.e., 28 naked barley and 23 waxy barley from supermarkets and 10 polished barley from local markets were collected, and their external quality were analyzed to provide basic information on brand barley. Among 51 brand barley, 56% were 1kg package and 25% were 800 g package and there was no significant difference ($1{\pm}3.62\;g$) between printed and actual weighs. The weight of 1,000 grains of naked barley and waxy barley ranged $18.6{\sim}26.7\;g$ and $14.6{\sim}24.7\;g$, respectively. Thousand grain weight of 38% of naked barley ranged $20{\sim}22\;g$, while that of 43% of waxy barley ranged $18{\sim}20\;g$. The ratio of normal grains was 88% and 94% for naked barley and waxy barley, respectively, when separated with 1.7 mm sieve. Although 82% of brand barley products were free from foreign substances, in 18% of brand barley products, sands, pieces of cloth and wood, other kinds of grain and insect larvae were found, Average test weight of brand barleys was $843g{\cdot}L^{-1}$ with range of $805{\sim}917g{\cdot}L^{-1}$. Water content was less than 14% in 7.8% of barley products, while it was $14{\sim}15%$ in 62.7% of them. Average whiteness of brand barley was 31.06, while waxy barley had higher whiteness with 27.28 than naked barley with 34.16. Heated water uptake rate of milled naked barley and milled waxy barley were 215.4% and 231.7%, respectively, while expansion rate of milled naked barley and milled waxy barley were 379.7% and 401.6%, respectively. Barley from local markets were as good as brand barley products in 1,000 grain weight, ratio of normal grains, inclusion of foreign substances, test weight, water content, whiteness, water uptake rate, and expansion rate, but they showed higher ratio of foreign substances included.

Drought Estimation Model Using a Evaporation Pan with 50 mm Depth (50mm 깊이 증발(蒸發) 팬을 이용한 한발 평가 모델 설정)

  • Oh, Yong Taeg;Oh, Dong Shig;Song, Kwan Cheol;Um, Ki Cheol;Shin, Jae Sung;Im, Jung Nam
    • Korean Journal of Soil Science and Fertilizer
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    • v.29 no.2
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    • pp.92-106
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    • 1996
  • Imaginary grass field was assumed suitable as the representative one for simplified estimation of local drought, and a moisture balance booking model computing drought was developed with the limited numbers of its determining factors, such as crop coefficient of the field, reservoir capacity of the soil, and the beginning point of drought as defined by soil moisture status. The maximum effective rainfall was assumed to be the same as the available free space of soil reservoir capacity. The model is similar to a definite depth evaporation pan, which stores rainfall as much as the available free space on the water in it and consumes the water by evaporation. When the pan keeps water less than a certain defined level, it is droughty. The model simulates soil moisture deficit on the assumed grass field for the drought estimation. The model can assess the water requirement, drought intensity, and the index of yield decrement due to drought. The influencing intensity indices of the selected factors were 100, 21, and 16 respectively for crop coefficient, reservoir capacity, and drought beginning point, determined by the annual water requirements as influenced by them in the model. The optimum values of the selected factors for the model were respectively 58% for crop coefficient defined on the energy indicator scale of the small copper pan evaporation, 50 mm for reservoir capacity on the basis of the average of experimentally determined values for sandy loam, loam, clay loam, and clay soils, and 65% of the reservoir capacity for the beginning point of drought.

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Analysis of Transshipment Type of Busan Port Utilizing Regional Hub Port Function (중심 항만 기능을 활용한 불산항의 환적 컨테이너 유형 분석)

  • Yang, Weon
    • Journal of Navigation and Port Research
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    • v.31 no.3 s.119
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    • pp.197-204
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    • 2007
  • Busan Port has been facing critical situation in terms of container handling volume, especially growth rate of transshipment(T/S) container of the year of 2006 was at a standstill. Annual average growth rate of T/S container during the period of 2003 to 2006 slowed down to 7.7% while it recorded over 34% to the period of 1999 to 2002. It has mainly resulted from the change of circumstance of Northeast Asian ports, that is, firstly mega carriers' increasing direct call to Northern Chinese ports such as Qingdao, Tianjin and Dairen effected to T/S container volume of Busan port, secondly start to operate deep-water port of Shanghai, thirdly Japanese super hub port project to handle their local containers at domestic ports. This paper aims to analyze the T/S type of inter-routes and hub and spoke and statistical status of Busan port. The purpose of the paper is to propose new concept which is to attract T/S container utilizing hub port function of Busan port in Northeast Asia It is that mega carriers are given dedicated terminals to use Busan port as T/S base in the region.