• Geomechanics and Engineering
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• 제7권5호
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• pp.539-552
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• 2014

A simplified probability-based design charts for stone column-improved ground have been presented based on the unit cell approach. The undrained cohesion ($c_u$) and coefficient of radial consolidation ($c_r$) of the soft soil are taken as the most predominant random variables. The design charts are developed to estimate the diameter of the stone column or the spacing between the stone columns by employing a factored design value of $c_r$ and $c_u$ so as to satisfy a specific probability level of the target degree of consolidation and/or a target safe load that needs to be achieved in a specified timeframe. The design charts can be used by the practicing engineers to design the stone column-improved ground by considering consolidation and /or bearing capacity of the improved ground.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 추계 학술발표회
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• pp.291-311
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• 2006

The acceleration of consolidation by stone columns was mostly analysed within the framework of a basic unit cell model (i.e. a cylindrical soil body around a column). A method of converting the axisymmetric unit cell into the equivalent plane-strain model would be required for two-dimensional numerical modelling of multi-column field applications. This paper proposes two practical simplified conversion methods to obtain the equivalent plane-strain model of the unit cell, and investigates their applicability to multi-column reinforced ground. In the first conversion method, the soil permeability is matched according to an analytical equation, whereas in the second method, the column width is matched based on the equivalence of column area. The validity of these methods is tested by comparison with the numerical results of unit-cell simulations and with the field data from an embankment case history. The results show that for the case of linear-elastic material modelling, both methods produce reasonably accurate long-term consolidation settlements, whereas for the case of elasto-plastic material modelling, the second method is preferable as the first one gives erroneously lower long-term settlements, where plastic yielding of stone column are ignored.

• Structural Engineering and Mechanics
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• 제56권4호
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• pp.507-534
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• 2015

The present work investigates the behavior of the embankment models resting on soft soil reinforced with ordinary and stone columns encased with geogrid. Model tests were performed with different spacing distances between stone columns and two lengths to diameter ratios (L/d) of the stone columns, in addition to different embankment heights. A total number of 42 model tests were carried out on a soil with undrianed shear strength $${\sim_\sim}10kPa$$. The models consist of stone columns embankment at s/d equal to 2.5, 3 and 4 with L/d ratio equal 5 and 8. Three embankment heights; 200 mm, 250 mm and 300 mm were tested for both tests of ordinary (OSC) and geogrid encased stone columns (ESC). Three earth pressure cells were used to measure directly the vertical effective stress on column at the top of the middle stone column under the center line of embankment and on the edge stone column for all models while the third cell was placed at the base of embankment between two columns to measure the vertical effective stress in soft soil directly. The performance of stone columns embankments relies upon the ability of the granular embankment material to arch over the 'gaps' between the stone columns spacing. The results showed that the ratio of the embankment height to the clear spacing between columns (h/s-d) is a key parameter. It is found that (h/s-d)<1.2 and 1.4 for OSC and ESC, respectively; (h is the embankment height, s is the spacing between columns and d is the diameter of stone columns), no effect of arching is pronounced, the settlement at the surface of the embankment is very large, and the stress acting on the subsoil is virtually unmodified from the nominal overburden stress. When $(h/s-d){\geq}2.2$ for OSC and ESC respectively, full arching will occur and minimum stress on subsoil between stone columns will act, so the range of critical embankment height will be 1.2 (h/sd) to 2.2 (h/s-d) for both OSC and ESC models.

• 보험의학회지
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• 제3권1호
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• pp.187-208
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• 1986

The conclusions which was acquired one renal cell carcinoma and renal disease 132 cases that was tested renal echogram among 4,499 cases for recent 16 months at medical department, Dae Han Kyoyuk Insurance company from August, 1984 to November, 1985 are as follows: 1. On bur ultrasonography, the echo of tumor was demonstrated with echogenicity as compared with renal parenchyme. 2. The case was stage I by Robson's modification method for pathologic histology. 3. There is no fever, typical triad of renal cell carcinoma and the result of serum biochemical test was within normal limit. 4. The frequency with disease was renal cell carcinoma(0.76%), ureteral stone(1.5%), multicystic kidney(2.27%), hydroureter(2.27%), Bilateral poly cystic kidney(4.55%), hydronephrosis(4.55%), renal agenesis(6.06%) renal calculi(18.18%), simple cyst(60.61%). 5. The frequency with age was 55/1200 case(4.58%) in $41{\sim}50$ years, 13/296 cases(4.39%) in $51{\sim}60$ years, 43/2144 cases(2.01%) in $31{\sim}40$ years, 14/791 cases(1.77%) in $21{\sim}30$ years, 7/53 cases(1.32%) more than 61 years and 0/15(0%) under 20 years. 6. The affected site of renal agenesis 8 cases was right side all. 7. In total renal disease 132 cases, the affected site of 126 cases except bilateral polycystic kidney 6 cases was right kidney 72 cases, left kidney the proportion of right to left 1.6:1 8. In total renal disease 132 cases except bilateral polycystic kidneys 6 cases, the patients affected with both side kidneys were 14 cases. 9. The affection rate with sex in total renal disease 132 cases was 98/2860 cases in male, 34/1819 cases in female and the former was about 2 times than the latter. 10. Classifying the stone with part, nephrolithiasis 24 cases were appeared high frequency, on the contray, ureteral stone 2 cases. 11. 2 cases of ureteral stone developed complication, hydronephrosis and hydroureter. 12. The linear array type transducer was not helpful for the diagnosis of lower ureteral calculi but for the lower ureteral calculi, we could see the stone with high echo in accompanying with acoustic shadowing. 13. In 24 cases of renal calculi, both side nephrolithiasis was 3 cases(12.5%). 14. In renal calculi, solitary stone could be seen extremely much and the number of stone was so much variable from 2 to 10. 15. In 26 cases with renal calculi and ureteral stone, the common clinical manifestation was a intermittent and slight pain. 16. In 80 cases of renal cyst, as one's get older, the affection rate of cyst extremely rised. 17. In bilateral polycystic kidney, large cyst had septum on the whole. 18. The patients with complication were 14 cases(10.6%) of total patients.

• Childhood Kidney Diseases
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• 제21권1호
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• pp.31-34
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• 2017

Tumor lysis syndrome is a serious complication of malignancy, resulting from the massive and rapid release of cellular components into the blood. Generally, it occurs after initiation of chemotherapy. The onset of spontaneous tumor lysis syndrome (STLS) before anti-cancer treatment is rare and occurs mostly in Burkitt lymphoma and non-Hodgkin's lymphoma. There are only a few case reports in children. Here, we report a case of STLS secondary to T-cell acute lymphoblastic leukemia (ALL), which presented with urinary stone and subsequent acute kidney injury with severe hyperuricemia. Occult malignancy should be considered in case of unexplained acute kidney injury with extreme hyperuricemia.

• 대한본초학회지
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• 제23권2호
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• pp.25-31
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• 2008

Objectives : In order to distinguish morphological characteristics of trunk bark and root bark of Ulmus davidiana var. japonica (Rehder) Nakai and the trunk bark and root bark of Hemiptelea davidii Planchon were sampled and compared in terms of their external and internal features with flour states according to their medical use, through microscopic examination. Methods : The slice of the tested material made by paraffin section technique was colored with Safranine Malachite Green contrast methods, and the flour of it was mounted by the liquid made by the same ratio of each of glycerin, acetic acid, and water, and then observed and photographed by olymphus-BHT. Results : 1. Internal Features 1) A large parenchymatous cell was observed in the phloem of the slice of both trunk bark and root bark of Ulmi Cortex, However, both of the trunk bark and root bark of Hemipteleae Cortex did not have parenchymatous cell in the phloem; instead, stone cells including much square crystal of calcium oxalate were distributed around fiber bundle, and the parenchymatous cell included much druse crystal of calcium oxalate. 2) In both the Ulmi Cortex and Hemipteleae Cortex, rhytidome was observed in trunk bark, but not in root bark, but in the parenchymatous cell of the root bark of the Ulmi Cortex contained starch grain. 2. Flour States 1) In the flour of root bark of the Ulmi Cortex, a large parenchymatous cell was observed. However, in the flour of trunk bark and root bark of Hemipteleae Cortex, no parenchymatous eel was found; instead, stone cell including square crystal of calcium oxalate and druse crystal of calcium oxalate were observed. 2) There was no remarkable difference between the trunk bark and root bark of Hemipteleae Cortex. However, starch grain was contained in the parenchymatous cell of the root bark of Ulmi Cortex but not in the trunk bark of it. Conclusions : There were some morphological differences in external, internal, and flour parts of Ulmi Cortex and Hemipteleae Cortex. In particular, there was a morphological difference in flour states between the trunk bark and root bark of Ulmi Cortex, it is possible to use microscope to distinguish their flour states.

• 원예과학기술지
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• 제31권4호
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• pp.407-414
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• 2013

본 연구는 '만풍배'의 생육단계 및 괘대 유무에 따른 과실의 해부학적 차이를 알아보고, 수확기 과실의 품질 및 착색특성 관찰을 통하여 '만풍배'의 생리적 특징을 이해하기 위하여 수행되었다. 만개기의 과실구조는 바깥쪽으로부터 외표피층, 아표피층, 유조직층, 내표피층으로 구성되어 있으며 아표피층을 이루는 세포 층수는 만개기부터 만개 후 77일까지 9-13층까지 최대로 증가하여 '만풍배'의 세포 분열 기간은 만개 후 77일까지로 조사되었다. 이 기간 동안 아표피층에서 유관속조직까지의 두께는 $73.1{\mu}m$부터 $195{\mu}m$까지 증가하였다. 석세포는 만개 후 7일부터 관찰되어 만개 후 49일에는 석세포군이 형성되어 있었다. 코르크층은 만개 후 49-77일 사이에 형성되었다. 성숙기인 만개 후 161일 '만풍배' 과실의 과피는 바깥쪽부터 코르크층은 4.5층, 아표피층은 7개의 세포층으로 구성되어 있었고 아표피층에는 탄닌이 분포해 있었다. '만풍배'의 괘대 유무에 따른 과실비대 및 조직발달을 비교한 결과, 괘대 초기에는 코르크층이 유대재배구에서 더 빨리 생겨나는 것으로 관찰되었으나 성숙기에는 3층 정도 무대재배구에서 더 두꺼워지는 것을 관찰할 수 있었다. 석세포군의 크기는 두 실험구 모두 불균일하게 분포되어 있었으며 과중은 무대재배구에서 더 높았으나 수확기의 당도는 괘대 유무에 따른 차이를 보이지 않았다. '만풍배'의 수확기 과중 등급은 301g부터 900g 이상까지 분포하였고, 그 중 551-800g의 과실이 총 수확량의 71.6%로 가장 많았으며 이 범위의 평균 과중은 677.2g이었다. 과실품질은 가용성 고형물 함량 $10.1-12.1^{\circ}Brix$, 산도 0.10-1.24%, 당산비 9.76-14.31로 분포하였으며 과중과 가용성 고형물 함량은 매우 높은 정의 상관관계를 나타내어 과실 크기가 클수록 가용성 고형물 함량도 높았다. 반면에 경도는 과중 및 가용성 고형물 함량과 높은 부의 상관관계를 나타내어 과실크기가 클수록 낮은 경향을 나타냈다. 과피의 황갈색 부분과 녹색 부분을 구분하여 코르크층 수와 함께 엽록소 함량을 조사한 결과, 코르크층은 황갈색 부분은 3.8층, 녹색부분은 3.5층으로 거의 차이를 보이지 않았으나 엽록소 함량은 녹색부분이 많은 것으로 조사되었다.

• Structural Engineering and Mechanics
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• 제30권1호
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• pp.99-117
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• 2008

This paper presents a comprehensive approach to the evaluation of macroscopic material parameters for natural stone and quarry masonry. To that end, a reliable non-linear material model on a meso-scale is developed to cover the random arrangement of stone blocks and quasi-brittle behaviour of both basic components, as well as the impaired cohesion and tensile strength on the interface between the blocks and mortar joints. The paper thus interrelates the following three problems: (i) definition of a suitable periodic unit cell (PUC) representing a particular masonry structure; (ii) derivation of material parameters of individual constituents either experimentally or running a mixed numerical-experimental problem; (iii) assessment of the macroscopic material parameters including the tensile and compressive strengths and fracture energy.

• KSBB Journal
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• 제8권5호
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• pp.431-437
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• 1993

적은 에너지로 적절한 유동충을 유지하기 위한 가 장 좋은 지지체는 bulk 빛 wet밀도가 가장 작은 활 성탄이며 최소및최적유동화속도가각각0.03cm/sec, 0.25cm/sec로 나타났다. 메탄 발효에 대한 유 기물 부하의 증가에 따라 모든 지지체의 CODe, 제 거율은 감소하였으나, 활성탄은 본 실험범위의 유기 물 부하에서 90% 이상의 제거율을 보였다. 이는 매 우 큰 비표면적을 가지는 활성탄에 많은 미생물이 흡착된 때문으로 사료된다. 유기물 부하 $16gCOD_{cr}/\ell.day$16gCODcr/day에서 흡착된 마생물의 양은 157mg/g이다. 천연 제올라이트와 Roast Celite를 비교하면 바표 면적만에 비례하여 미생물의 양이 증가하지는 않음 을 알 수 았으며, 동엘한 비표면적을 가지는 Roast Celite와 부석을 비교하면, 유기물 제거능이 Roast Celite가 우수한데 이로부터 표면의 거칠기가 상대적으로 크고 표면전하가 양전하를 띠는 것이 마생물 흡착에 중요한 것으로 사료된다. 혐기성 유동층 반 응기에 이용할 지지체는 유체의 shear stress를 감소 시켜서 미생물 흡착을 증대시키기 위하여 될 수 있으면 작은 wet밀도와 작은 유동화 속도를 가져야 한다고 사료된다.

• 한국식품영양과학회지
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• 제32권3호
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• pp.370-374
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• 2003

홍삼 분쇄의 신 가공 기술로서 비충격 분쇄방식인 cell cracker의 공장 적용 가능성을 제시하고 홍삼분말의 품질고급화에 기초자료로 활용하고자, 기존의 hammer mill(충격분쇄방식)과 cell cracker에 의한 분쇄방식으로 홍삼분말을 제조한 후 물성, 표면구조적 특성 및 관능적 특성을 측정하였다. 입도분석에서 sieve shaker로 분석한 결과, 100 mesh 이상은 모두 95%수준으로 비슷한 분포를 나타냈고 120 mesh 이상은 hammer mill로 분쇄한 홍삼분말이 높았으며 그 밖의 각 mesh별 입도분포는 큰 차이를 나타내지 않았다. Laser scattering analyzer로 분석한 결과 hammer mill로 분쇄한 홍분말의 입도분포는 최소 0.77$\mu\textrm{m}$에서 최대 128.07$\mu\textrm{m}$으로, cell cracker로 분쇄한 홍삼분말 4.24~180.07$\mu\textrm{m}$보다 분포가 넓었으며, 평균 입자 크기는 cell cracker로 분쇄한 홍삼분말이 크고 표준편차는 hammer mill로 분쇄한 홍삼분말이 크게 나타났다. 비표면적은 hammer mill로 분쇄한 홍삼분말이 1.42 $m^2$/g로 cell cracker로 분쇄한 홍삼분말 0.59 $m^2$/g보다 높게 나타났고, 표면구조적 특성은 hammer mill로 분쇄한 홍삼분말은 크고 작은 입자가 불균일하게 분포하고 있으며, 개별입자의 형태는 부등형의 거칠게 연마된 돌 모양에 가깝고 표면은 작고 부드러운 솜털모양을 하고 있는 반면에, cell cracker로 분쇄한 홍삼분말은 입자크기가 상대적으로 고르게 분포하고 있으며 개별입자의 형태는 부등형의 조각난돌 모양의 형태로 관찰되었다.