• 한국조경학회지
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• 제39권5호
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• pp.127-140
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• 2011

수당의 장안성이 전근대 동아시아 수도의 전범이 될 수 있었던 것은 왕도로서의 권위를 확보한 전통적 이데올로기가 공간에 이상적으로 체현되고 있기 때문이다. 본 연구에서는 장안성의 형성과 도성 형식에 자연환경요소가 어떻게 이용되었는지 살피고, 수로 조성에 대한 제반 고찰을 통해 장안성의 수체계가 도성의 위상 형성과 도시의 기능에 어떤 역할을 하였는지 알고자 하였다. 수당 양대(兩代)를 거치면서, 장안성 일대는 '거(渠)'라는 수리시설을 통한 정교한 수체계가 구축되었다. 이 수리시설은 원(原)과 하천이 발달한 주변 환경을 적절히 이용한 것으로, 주로 관개용수, 도시생활용수, 원림조성의 기반시설, 저류시설 등의 도시 시설로 세분화하여 계획되었다. 이들은 농업생산성을 향상시켜 장안성의 도시 경쟁력에 일조하였을 뿐만 아니라, 도시기반시설로서의 역할을 수행하여 편리하고 윤택한 삶의 질을 보장하였다. 또, 쾌적하고 아름다운 도시경관이 유지될 수 있게 하였다. 그리고 수체계의 이러한 도시적 효과는 곧 도성의 위상 제고로 이어졌다. 장안성은 합리적이고 실용적인 수체계 구축을 통해 도시적 기능을 최적으로 수행하였을 뿐만 아니라, 이를 통해 수도로서의 위상을 직접적으로 획득하고 있었다는 점에서 평가받을 만하다.

• Restorative Dentistry and Endodontics
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• 제43권1호
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• pp.2.1-2.10
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• 2018

Objectives: To determine the effect of size and insertion depth of irrigation needle on the amount of apical extruded debris and the amount of penetration depth of sealer using a confocal laser scanning microscope (CLSM). Materials and Methods: Twenty maxillary premolars were assigned to 2 groups (n = 10), according to the size of needle tip, 28 G or 30 G. Buccal roots of samples were irrigated with respective needle type inserted 1 mm short of the working length (WL), while palatal roots were irrigated with respective needle type inserted 3 mm short of the WL. Prepared teeth were removed from the pre-weighed Eppendorf tubes. Canals were filled with F3 gutta-percha cone and rhodamine B dye-labeled AH 26 sealer. Teeth were transversally sectioned at 1 and 3 mm levels from the apex and observed under a CLSM. Eppendorf tubes were incubated to evaporate the irrigant and were weighed again. The difference between pre- and post-weights was calculated, and statistical evaluation was performed. Results: Inserting needles closer to the apex and using needles with wider diameters were associated with significantly more debris extrusion (p < 0.05). The position of needles and level of sections had statistically significant effects on sealer penetration depth (p < 0.05 for both). Conclusions: Following preparation, inserting narrower needles compatible with the final apical diameter of the prepared root canal at 3 mm short of WL during final irrigation might prevent debris extrusion and improve sealer penetration in the apical third.

• 한국농공학회지
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• 제23권2호
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• pp.61-69
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• 1981

The paddies in the hillsides in Gonggeun-myeon, Hoingseong-gun, Kangweon-do keep a steep slope and run in and out. A land consolidation in such an area, therefore, will require high ratio of land loss and a large amount of earth moving if it follows the existing design criteria to separate drainage and irrigation ditches in a scheme. Due to the consequent decrease in construction cost, the project has not been envisaged. in order to secure the introduction of small-medium size farm machineries into the paddies, farm plots were planned to be straight and drainage with taking care of topography. Findings from the comparison of methodologies are as follows. 1. In places with a solpe of more than 1/30, a reduction in earth moving can be expected with parallel plots to the contours. 2, For the sake of effective using of farm machineries, it is thought that a plot should be running straight parallel to the contours and the ratio of length and width of a plot be more than six. 3. In places with a slop of more than 1/10, a reduction in earth moving and a effective introduction of farm-machineries can he expected with straight parllel plots to the contours. But it is undesirable to introduce a scheme in this places because of the difficulties in acreage computation and farmers' hesitation. 4. The system with a canal for both irrigation and drainage is highly effective to decrease the ratio of land loss as well as construction cost. 5. Parallel plots to the contours and a canal for both irrigation and drainage are highly effective in the decrease in construct cost. 6. To avoid the subdivision of a cooperation in farming is desirable of a plots, has more than two owners.

• 한국농공학회논문집
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• 제63권4호
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• pp.1-12
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• 2021

Agricultural drought is a natural phenomenon that is not easy to observe and predict and is difficult to quantify. In South Korea, the amount of agricultural water used is large and the types of use are varied, so even if an agricultural drought occurs due to insufficient precipitation, the drought actually felt in the irrigated area is it can be temporally and spatially different. In order to interpret the general drought in the past, drought disasters were evaluated using single indicators such as drought damage area, precipitation shortage status, and drought index, and a comprehensive drought management system is needed through drought diagnosis survey. Therefore, we intend to conduct research on agricultural drought assessment and diagnosis using re-evaluation of agricultural facilities and irrigation water supply network due to changes in various conditions such as climate change, irrigation canal network, and evaluation of water supply capacity of agricultural facilities. In this study, agricultural drought diagnosis was conducted on two agricultural reservoirs located in Sangju, Gyeongsangbuk-do, with structural or non-structural evaluations to increase spatiotemporal water supply and efficiency in terms of water shortages. The results of the agricultural drought diagnosis evaluation can be used to identify irrigated areas and canal network vulnerable to drought and to prioritize drought response.

• 한국농공학회지
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• 제24권4호
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• pp.57-68
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• 1982

The paddy fiels slope located in Kangweon province Hwyongsung gun Gonggeun myon Shinchonri was considerably steep and so it was impossible to economically consolidate the field up to date. But for the porpose of farm mechanization, the field (32. 27ha) was consolidated by the auther under the assitance of the Ministry of Agriculture and Fishery and,;the Administration of Kangweon province. This paddy field consolidation was caused by the treatise on "Land-consolidation methods for farm mechanization in the steep-sloped paddy field", of which the auther is the same. The constrution was carried out from September, 1981 to April, 1982. During the 4esign and construction, some Peculiarities were found and discussed. That is, in design, besides the common condititions for a design, some special conditions were considered and written below; (1) The ranges of field slope in this design were 1/100-1/30. (2) Long sides of the land readjustment blocks must be arranged abreast contour line, and so they make the amount of cutting and banking decreased so as to take the maximum advantage of the configuration of the field. (3) In design, the main principles of dividing blocks were written below; i) First of all, long side of a block should be drawn straight abreast a contour line. ii) Long side of a block should arrange abreast contour line and make its length 100-150m, if not, l)reak the side in order to make a bended rectangle. iii) Length of a short side should be determinded within differences of elevation (0.6 -1. 2m) between the two adjacent blocks toward the normal to a contour line. iv) Length of a short side should be above 15m and the ratio of long and short side should be slso kept 1: (4-6). v) A new field surface leveling was determinded from the elevation which produce the least amount of cuttingand banking within the range of 0.6-1. 2m diffe rences of elevation between the two adjacent blocks. vi) In the course of dividing blocks with the same width along the line which was normal to a contour line, all blocks connot keep their shape in a retangle because of steep slope of the field and so on, and so it was also necessory to make some non-retanglar and small blocks such as a trianglar or trapezoidal shape, which was impossible to use some of farm machinery. But because this non-rectanglar and small blocks were divided, larger and many rectanglar blocks can be divided and construction cost can also be lowered. According to the conditions discussed above, the paddy field consolidation project designed and constructed. And the results of this study were obtained as below; (1) Three-forth of total cost of this paddy field consolidation was not construction cost, and these cost consist of land grading (1/4), road and canal construction cost (1/4) and the other cost (1/4) such as surveying or materials and 56 on. (2) The steeper the land slope, the greater cost was assigned for road and canal construction, and than land grading. (3) Curtailment of the road and canal construction cost depended on simplificating their strutures. (4) In the case of the land slopes were low, the land grading cost was high by 1: 1.4 in comparison with the road and canal construction cost, and conversely when the slops were steep, the road and canal construction cost was high by 1 : 5 in compa- rison with the land grading cost. (5) The densities of irrigation canal, drainage canal and trunk and branch road were 150. Sm/ha, 60. im/ha and 17. 4m/ha respectively. The density of irrigation canal of the area was high by 2 times in comparison with the average one of Kangweon Province, and the others were nearly the same. (6) Most farmers (above 85%) knew the effects of paddy field consolidation. The effects are; 1) Improvement of irrigation 2) Improvement of farm management 3) Improvement of transportarion 4) farm mechanization and 5) grouping of the scattered land. And the more farm modernization was accomplished by these projects, the more farmers wanted to live in their land. (7) In spite of the very steep sloped paddy field, the diminution rate of the net farm land caused by consolidation was 7.7% which was nearly the same as the one of Chulweon plain of Kangweon province. Land grading cost was 971, OOOwon/ha which was rather cheap by 13.2% than the one of Ghulweon plain, and unit construction cost was 5, 341, OOOwon/ha (included soil addition) which was also nearly the same as the one of Chulweon plain and FNFIA (The federation of national farmland improvement association).

• Restorative Dentistry and Endodontics
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• 제28권5호
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• pp.425-430
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• 2003

The purpose of this study was to evaluate the clinical applications of the Sodium Dichloroisocyanurate effervescent tablet as a routine root canal irrigant by performing several in vitro tests such as $Cl^{-}$ content. cytotoxicity. antimicrobial effect as well as its pH level compared to the equivalent concentration of sodium hypochlorite solution. 1. Sodium Dichloroisocyanurate demonstrated lower level of $Cl^{-}$ concentration than each dilution of sodium hypochlorite solution. Both solution has increased level of $Cl^{-}$ as the concentration of each solution increased. There was no significant change of $Cl^{-}$ concentration in sodium hypochlorite as time goes by. However. $Cl^{-}$ concentration in Sodium Dichloroisocyanurate was increased. 2. The antimicrobial effects of both solutions were increased when their concentrations were increased. One day after dilution. antimicrobial effect of Sodium Dichloroisocyanurate was slightly higher than sodium hypochlorite. however. there was no difference in 1 week dilution solution. One month dilution solution of sodium hypochlorite still retain its activity. but antimicrobial effect of Sodium Dichloroisocyanurate was drastically decreased 1 month after dilution. 3. The cytotoxicity of Sodium Dichloroisocyanurate was rather higher than same concentration of sodium hypochlorite solution until 1 week after dilution. Then in 1 month. cytotoxicity of Sodium Dichloroisocyanurate was decreased than that of 1 week dilution solution. especially 4% Sodium Dichloroisocyanurate solution has almost no toxicity. However. 1% and 2% sodium hypochlorite solution has unchanged moderate degree of cytotoxicity after the dilution. Furthermore. 4% sodium hypochlorite solution showed high level of toxicity. 4. The pH level of Sodium Dichloroisocyanurate showed that the solution was weak acid (pH5). On the other hand. sodium hypochlorite was revealed as a strong alkaline solution (pH12). There was no change in pH following the dilution of each solution. As results. Sodium Dichloroisocyanurate solution fully satisfy the basic requirements as a root canal irrigation solution. However. we strongly recommend to use this solution clinically in low concentration and try to apply into the root canal within 1 week after dilution.

• 한국농공학회논문집
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• 제65권5호
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• pp.51-68
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• 2023

Due to the recent integrated water management policy, it is important to identify a reliable supply amount for establishing an agricultural water supply plan. In order to identify the amount of agricultural water supply, it is essential to calculate the discharge by measuring the water level and flow velocity of reservoirs and canal agricultural water, and quality control to ensure reliability must be preceded. Unlike agricultural reservoirs, canal agricultural water are more sensitive to the surrounding environment and reservoir irrigation methods (continuous, intermittent irrigation, etc.), making it difficult to estimate general water level patterns and at the same time a lot of erroneous data. The Korea Rural Community Corporation is applying a filter technique as a quality control method capable of processing large quantities and real-time processing of canal agricultural water level data, and applicability evaluation is needed. In this study, the types of errors generated by the automatic water level measurement system were first determined. In addition, by using the manual quality control data, a technique with high applicability is derived by comparing and analyzing data calibrated with Gaussian, Savitzky-Golay, Hampel, and Median filter techniques, RMSE, and NSE, and the optimal parameters of the technique range was derived. As a result, the applicability of the Median filter was evaluated the highest, and the optimal parameters were derived in the range of 120min to 240min. Through the results of this study, it is judged that it can be used for quantitative evaluation to establish an agricultural water supply plan.

• Restorative Dentistry and Endodontics
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• 제33권6호
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• pp.560-569
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• 2008

본 review 논문의 목적은 통상의 근관치료로 해결되지 않는 persistent periapical lesion의 원인이 되는 주요 세균을 제거하고자 시행한 여러가지 실험을 비교분석하여 과연 (1) Enterococcus faecalis가 근관치료 실패의 주요 원인균인지 (2) 그리고 과연 그렇다면 근관치료에 실패한 증례에서 E. faecalis와 biofilm을 제거할 수 있는 치료 protocol이 있는 것인지를 확인하여 보다 나은 근관치료 성공을 위한 치료 protocol의 확립과 앞으로의 연구방향을 재조명하는 것이다. 지금까지 진행되어온 연구 결과에 대한 객관적인 분석이나 적절한 평가가 이루어지지 않은 가운데 어떤 특정한 연구를 통해 E. faecalis를 제거하는데 유의성있는 효과를 보인다고 알려진 세척액이나 약제를 막연한 기대감을 가지고 실제 임상에 사용하고 있는 실정에서 현재 진료실에서 사용하고 있는 치료 protocol에 대한 검증이 절실한 시점에서 review해 본 결과 현재까지 진행되어 왔던 여러 연구 결과를 통해 확신할 수 있는 것은 치료 protocol에 따라 현재 사용하고 있는 근관세척액이나 근관내 약제만으로도 E. faecalis나 그 biofilm을 대부분 제거할 수 있다는 사실이다. 하지만 이 그 protocol에 따라 근관치료 술식을 충실하게 이행한다 해도 근관치료가 100% 성공한다고 보장할 수는 없다. 물론 세균이 아닌 다른 요소에 의해 근관치료의 실패가 일어난다고도 할 수 있지만 그보다는 결국 체내의 면역반응에 저항하는 세균의 능력에 기인하는 것으로 보인다. 따라서 높은 수준의 치료 성공률을 지속적으로 유지하기 위해서는 위에서 언급된 바와 같은 제대로 된 치료 protocol을 따라 근관치료를 진행하면서 좀더 나은 결과를 얻기 위해 새로운 protocol을 개발하고 정립하는 과정이 계속되어야 한다.

• Restorative Dentistry and Endodontics
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• 제24권2호
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• pp.399-407
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• 1999

근관 형성중 잔사의 치근단 정출은 치근단 조직의 반응을 유발하여 동통과 부종을 일으키며 치유를 지연시킬 수 있다. 본 연구의 목적은 수종의 기구와 방법을 사용하여 근관을 형성하고 이에 따른 근관 잔사의 치근단 정출량을 비교함으로써 잔사의 정출을 최소화 할 수 있는 기구 조작법을 알아보고자 하는 것이다. 120개의 발거된 사람의 하악 절치에서 근관형성중 치근단으로 정출되는 잔사의 양을 비교하였다. 첫 번째 실험에서는 40개의 치아를 10개씩 4군으로 나누어 2.52% 치아염소산나트륨용액으로 근관을 세척하면서 다음의 4방법 중 하나를 이용하여 근관을 형성하였다. 수동 스테인레스 스틸 K-화일을 이용하여 step-back technique, crown-down pressureless technique으로 근관을 형성하였고 전동 니켈 티타늄 기구로는 Quantec SC series 2000과 Profile .04 taper series 29를 이용하여 근관을 형성하였다. 두 번째 실험에서는 80개의 치아를 16개씩 5군으로 나누고 근관 세척에 의한 잔사의 치근단 정출 영향을 배제하고자 근관 세척을 시행하지 않고 근관을 형성하였다. 이 때에는 첫 번째 실험의 방법중 Quantec SC series 2000 대신에 Quantec SC 및 Quantec LX를 이용하여 근관을 형성하였고 나머지는 첫 번째 실험과 동일하게 시행하였다. 각 치아로부터 정출되는 잔사를 용기에 모아 24 시간동안 건조시킨 후 전자 저울로 무게를 측정, 비교하여 다음과 같은 결과를 얻었다. 근관 세척을 시행한 경우와 시행하지 않은 경우 공히 step-back technique을 사용한 군에서는 다른 군에 비해 현저히 많은 량의 치근단 정출 잔사가 나타났다. 그러나, crown-down technique을 이용하여 근관 형성한 군과 수종의 Ni-Ti 파일을 이용하여 전동으로 근관 형성한 군들 사이에는 정출 잔사량에 유의한 차이가 나타나지 않았다. 따라서, 본 실험에 사용된 수동 및 전동 기구의 종류는 근관 잔사의 치근단 정출에 영향을 미치지 않는 것으로 생각되며, 근관잔사의 치근단 정출을 최소화하기 위해서는 수동 및 전동 기구 공히 step-back 방법에 의한 filing 동작보다는 crown-down technique의 reaming 동작을 사용하여 근관을 형성하는 것이 바람직하다고 사료된다.

• 대한치과의사협회지
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• 제58권5호
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• pp.276-283
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• 2020

Objectives: The aim of this study was to evaluate the efficacy of CK files as an ultrasonic instrument, and to determine most efficient file size for smear layer removal. Materials and Methods: Thirty-six extracted human mandibular premolars with single, straight root canals and mature apices were mechanically prepared and randomly divided into three groups. Group 1 (Control) underwent conventional needle irrigation, Group 2 (CKS) underwent passive ultrasonic irrigation with a #20 CK file, and Group 3 (CKL) underwent passive ultrasonic irrigation with a #30 CK file. After preparation and irrigation, all teeth were dried and split with a chisel to obtain the mesial and distal half of their roots. Each sample was evaluated using a scanning electron microscope, and data were analyzed using the Kruskal-Wallis and Mann-Whitney rank sum tests (p<0.05). Results: The CKS group showed less debris in the apical third than the other groups (p<0.05). In this section, no significant difference was observed among the other groups. And, there was no significant difference among any groups for the middle third section. Conclusion: This study showed that PUI with #20 CK file removed more smear layer compared to using #30 CK file at the apical third of the root canal.