• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.6
• /
• pp.643-651
• /
• 2001

Paddlewheel-driven circulation in a culture pond has been simulated based on the depth integrated 2 dimensional hydrodynamic model. Acceleration by paddlewheel is expressed as shaft force divided by water mass discharged by paddlewheel blades. The model has been calibrated and applied to culture ponds as following steps:- i) The model predicted velocities at every 10 m along longitudinal direction from the paddlewheel. The model was calibrated comparing the results with the measured values at mass correction factor $\alpha$ and dimensionless eddy viscosity constant $\gamma$, respectively, in a range $15\~20$ and 6. ii) Wind shear stress was simulated under conditions of direction $0^{\circ}C,\;90^{\circ}C\;and\;180^{\circ}C$ and speed 0.0, 2.5, 5.0 and 7.5 m/s. Change rate of current speed was <$1\%$ at wind in parallel or opposite direction to the paddlewheel-driven jet flow, while $4\%$ at orthogonal angle. iii) The model was then applied to 2 culture ponds located at the Western coast of Korea. The measured and predicted currents for the ponds were compared using the regression analysis. Analysis of flow direction and speed showed correlation coefficients 0.8928 and 0.6782 in pond A, 0.8539 and 0.7071 in pond B, respectively. Hence, the model is concluded to accurately predict circulation driven by paddlewheel such that it can be a useful tool to provide pond management strategy relating to paddlewheel operation and water quality.

• Journal of Gastric Cancer
• /
• v.6 no.1
• /
• pp.31-35
• /
• 2006

Purpose: A primary adenosquamous carcinoma of the stomach is relatively rare, accounting for only about 0.5% of all gastric cancers. However, its histopathologic characteristics are still unclear, and the most appropriate form of therapy has not been established yet. Materials and Methods: We retrospectively reviewed the clinicopathologic features of 8 patients with pathologically confirmed primary adenosquamous carcinomas out of 8,268 patients who underwent gastric cancer surgery at Samsung Medical Center between September 1994 and December 2004. Results: The median age of the 8 patients was 49 ($41{\sim}69$) years, and the male : female ratio was 5 : 3. In 3 patients, the tumor was located at the mid body of the stomach, and in 5 patients, at the lower body or antrum. The tumor sizes were $2.5{\sim}8cm$. Seven patients showed metastases to the regional lymph nodes. The UICC stage distribution were: 5 stage II, 2 stage III, and 1 stage IV. In the stage IV patient, a palliative gastrojejunostomy was performed, and he died 5 months after surgery. Of the 7 patients who underwent a radical gastrectomy and adjuvant chemotheratpy, the median survival was 34 ($12{\sim}66$) months, 2 patients died of cancer recurrence, and 4 patients are being followed up without evidence of recurrence. Conclusion: As for an adenocarcinoma of the stomach, a radical gastrectomy including regional lymph node dissection and postoperative adjuvant therapy should be performed for appropriate treatment of an adenosquamous carcinoma of the stomach.

• Journal of Aquaculture
• /
• v.16 no.4
• /
• pp.233-239
• /
• 2003

Growth and activities of digestive enzymes in slime flounder (Microstomus achne) larvae were measured from hatching to near the end of larval development (day 58). Larvae reared under starved and fed conditions and the changes of acid phosphatase (ACPase) specific activity, alkaline phosphatase (ALPase) specific activity, trypsin-like enzyme activity and pepsin-like enzyme activity were described with growth and developmental stage of larvae. Total length of the starved larvae was gradually increased for 7 days post hatching and then almost unchanged. Total length of the fed larvae ranged from 5.13$\pm$0.178 mm at the day of hatching to 13.43$\pm$1.395 mm at 58 days after hatching. In starved group, dry body weight decreased from 0.l0$\pm$0.020 mg at the day of hatching to 0.05$\pm$0.012 mg at 12 days after hatching. Dry body weight of fed larvae decreased during the prelarva stage like starved group and then gradually increased. ACPase and ALPase specific activity in the starved larvae increased until all larvae died, however those activities in the fed larvae increased until 20 days and then decreased until 58 days after hatching, with no significant difference between groups. Trypsin-like enzyme activity in the starved larvae was unchanged until 3 days and then was the highest on 5 days after hatching, but not detected after completion of yolksac absorption. Those of fed larvae decreased until 3 days and sharply increased until completion of yolksac absorption. The highest trypsin-like enzyme activity in the fed group was observed at 20 days after hatching. Trypsin-like enzyme activity in the fed larvae was significantly higher than that in the starved larvae from 8 days after hatching. Pepsin-like enzyme activity was increased in 5 days after hatching in both groups. There was significant difference at 8 and 10 days after hatching between both groups. Based on above results, digestive enzyme activities were correspondingly changed to a growth and morphological transformation. Trypsin-like enzyme and pepsin-like enzyme activities are able to be a useful indices for health and growth status in larval slime flounder, because there was significant difference in digestive enzyme activities with developmental stages, growth or feed supply.

• Sleep Medicine and Psychophysiology
• /
• v.6 no.1
• /
• pp.52-60
• /
• 1999

Objectives: With the object of finding the appropriate conditions and algorithms for dimensional analysis of human EEG, we calculated correlation dimensions in the various condition of sampling rate and data aquisition time and improved the computation algorithm by taking advantage of bit operation instead of log operation. Methods: EEG signals from 13 scalp lead of a man were digitized with A-D converter under the condition of 12 bit resolution and 1000 Hertz of sampling rate during 32 seconds. From the original data, we made 15 time series data which have different sampling rate of 62.5, 125, 250, 500, 1000 hertz and data acqusition time of 10, 20, 30 second, respectively. New algorithm to shorten the calculation time using bit operation and the Least Trimmed Squares(LTS) estimator to get the optimal slope was applied to these data. Results: The values of the correlation dimension showed the increasing pattern as the data acquisition time becomes longer. The data with sampling rate of 62.5 Hz showed the highest value of correlation dimension regardless of sampling time but the correlation dimension at other sampling rates revealed similar values. The computation with bit operation instead of log operation had a statistically significant effect of shortening of calculation time and LTS method estimated more stably the slope of correlation dimension than the Least Squares estimator. Conclusion: The bit operation and LTS methods were successfully utilized to time-saving and efficient calculation of correlation dimension. In addition, time series of 20-sec length with sampling rate of 125 Hz was adequate to estimate the dimensional complexity of human EEG.

• Tuberculosis and Respiratory Diseases
• /
• v.41 no.6
• /
• pp.632-643
• /
• 1994

Background: The objective responses of cisplatin and etoposide (PVP) combination chemotherapy as second-line therapy following CAV was high (40~50%) and, in several reports, PVP yields survival results that are at least as good as those obtained with cyclophosphamide or doxorubicin-based regimens and with less host-related toxicity in chemotherapy-naive patients. We conducted a phase II study to evaluate the effect of a combination of cisplatin and etoposide as a fitst-line therapy in patients with small cell lung cancer. Methods: Sixty-one previously untreated small cell lung cancer patients with measurable lesion (s) received cisplatin(30 $mg/m^2$ IV, day 1~3) and etoposide(100 $mg/m^2$ IV, day 1~3). In patients with limited disease, after completion of 6 cycles of PVP chemotherapy, chest and prophylatic brain irradiation was performed in case of complete responder, chest irradiation on1y in partial responder. Results: 1) Of 55 evaluable patients, 13(24%) had a complete response and 29(53%) had a partial response. 2) The median survival time was 55.8 weeks for all patients(N=55), 61.1 weeks for limited disease(N=31), 51.3 weeks for extensive disease(N=24). 3) The response duration was 29.1 weeks for responders(N=42). 4) There was no significant prognostic factors influencing response rates. 5) The toxicity was tolerable and there was no treatment-related deaths. Conclusion: The PVP combination chemotherapy as a first-line therapy was effective and well-tolerated in patients with small cell lung cancer.

• Journal of Korean Society of Forest Science
• /
• v.94 no.6
• /
• pp.370-376
• /
• 2005

Sarcodon aspratus is well known as a natural edible mushroom and a symbiotic mycorrhizal fungus with oaks. This study was conducted to clarify the effects of environmental conditions on the fruiting of S. aspratus on the hillslope of Wolak Mt., Jecheon city, Chungbuk, South Korea. Soil moisture and soil temperature in S. aspratus colony were measured hourly and compared with those in the non-colony soil. The mean soil moisture during the mushroom development was 14.3% in the colony soil and 16.4% in the non-colony soil. The S. aspratus colony soils showed 2.1% less soil moisture. The mean soil temperature was $16.8^{\circ}C$ in the colony soil and $16.5^{\circ}C$ in the non-colony soil. The S. asprauts colony soils showed slightly higher temperature. It is considered that more soil water was consumed and more energy was emitted during the mycelial elongation and the mushroom development. The development of S. aspratus seems similar to that of T. matsutake which is known to be considerably affected by soil moisture, daily maximum air temperature, daily minimum air temperature and daily minimum soil temperature. The season of S. aspratus development ranges from the end of August to the beginning of October. And Ellino phenomenon and its unusual change in the weather seems to affect primodia and fruiting body development. Especially if daily minimum soil temperature continues to become higher than $20^{\circ}C$, the damage of primodia and its fruiting body was frequently observed in the field plots during the last few years recently.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.17 no.1
• /
• pp.43-54
• /
• 1989

In recent years plants have increasingly become in inferior part of the interior designing of large buildings. In 28 large buildings selected at random in Seoul City have been subjected to studies on utilization status of fille interior landscape plants. The results obtained were as follows. 1. Plant class found in Interior of large buildings were 59 class, especially Dracaena were the most predominent plants among them, and then comes Monstera, Phiodendron, Schefflera, and Washingtonia in that order. 2. The most abundant ornamental plant cultivars were Monstera adansoii(Monstera perutusa cv.), and then comes Schefflera arboricora(Schefflera Hong Kong cv.), Washingionia rubusta (Washingtonia palm). Rhapis excelsa, and Diffenbachia(Hawaii Snow cv.) in that order. 3. Foliage plants among the interior landscape plants showed 99.5 percent and Woody plants and Bonsai plants showed each 0.4, 0.1 percent. 4. Climbing foliage plants found in 28 large building observed For the present study were 9 cultivar, and the most abundant plants were Hedera (pittsburgh cv.) and Epipremnum (Marble Queen cv.) pl anted to clustered planting. 5. A majority of plants used to plastic pot, and most of 71an1s place on the floor. 6. Height of plants ranging less then 50cm were more frequently found, but ranging from 50cm to 2.0m were 4.3 percent and the most predominent height of plants were Canariensis showed 4m in the large buildings. 7. Interior light intensity in large building were shortage, therefore artificial lamp for formal growing needed to be equipped. 8. Purpose growth of interior plants were to in order visitors. 9. 7he superintendents prefered to used pot-stand. 10. The most important environment factor for plant growing were light, humidity, and water.

• Computational Structural Engineering
• /
• v.7 no.3
• /
• pp.95-103
• /
• 1994

The safety related components in the nuclear power plant should be designed to withstand the seismic load. Among these components the integrity of reactor internals under earthquake load is important in stand points of safety and economics, because these are classified to Seismic Class I components. So far the modelling methods of reactor internals have been investigated by many authors. In this paper, the dynamic behaviour of reactor internals of Yong Gwang 1&2 nuclear power plants under SSE(Safe Shutdown Earthquake) load is analyzed by using of the simpled Global Beam Model. For this, as a first step, the characteristic analysis of reactor internal components are performed by using of the finite element code ANSYS. And the Global Beam Model for reactor internals which includes beam elements, nonlinear impact springs which have gaps in upper and lower positions, and hydrodynamical couplings which simulate the fluid-filled cylinders of reactor vessel and core barrel structures is established. And for the exciting external force the response spectrum which is applied to reactor support is converted to the time history input. With this excitation and the model the dynamic behaviour of reactor internals is obtained. As the results, the structural integrity of reactor internal components under seismic excitation is verified and the input for the detailed duel assembly series model could be obtained. And the simplicity and effectiveness of Global Beam Model and the economics of the explicit Runge-Kutta-Gills algorithm in impact problem of high frequency interface components are confirmed.

• Asian Journal of Turfgrass Science
• /
• v.24 no.1
• /
• pp.16-23
• /
• 2010

Mowing is an important practice in golf course management. Mowing interval and height can affect net photosynthesis of turfgrass and finally shoot density, tillering, rooting and regrowth of turfgrass. The objectives of this study were to investigate the regrowth rate of zoysiagrass shoot under different mowing height for determination of proper mowing frequency. Recommended mowing interval were calculated by a rule that no more than 33% of the above ground height be removed in a single mowing. Daily shoot growth of zoysiagrass at 10 mm mowing height were 2.1~4.7 mm (July), 1.9~2.9 mm (August), 0.9~1.5 mm (September), and 0.6 mm (October). These results indicate that recommended mowing interval were 1.1~2.3 day for July, 1.7~2.4 day for August, 3.5~5.4 day for September, and 8.5 day for October, respectively. Daily shoot growth of zoysiagrass at 15 to 17 mm mowing height were 4.0~5.3 mm (July), 2.9~4.5 mm (August), 1.4~3.7 mm (September), and 1.3 mm (October). These results indicate that recommended mowing interval were 1.4~1.9 day for July, 1.7~2.5 day for August, 2.3~6.3 day for September, and 6.8 day for October, respectively. Daily shoot growth of zoysiagrass at 18 to 21 mm mowing height were 3.5~4.7 mm (July), 2.9~4.9 mm (August), and 1.5~1.8 mm (September). These results indicate that recommended mowing interval were 1.9~2.6 day for July, 1.8~3.1 day for August, and 5.9~7.0 day for September, respectively. Daily shoot growth of zoysiagrass at 50 mm mowing height were 4.6~4.9 mm (July), 5.0~6.5 mm (August), and 2.5~4.7 mm (September). These results indicate that recommended mowing interval were 5.1~5.4 day for July, 3.9~5.0 day for August, and 5.3~9.8 day for September, respectively.

• Progress in Medical Physics
• /
• v.9 no.2
• /
• pp.77-88
• /
• 1998

Wedge shaped isodoses are desired in a number of clinical situations. Hard wedge filters have provided nominal angled isodoses with dosimetric consequences of beam hardening, increased peripheral dosing, nonidealized gradients at deep depths along with the practical consequendes of filter handling and placement problems. Dynamic wedging uses a combination of a moving collimator and changing monitor dose to achieve angled isodoses. The segmented treatment tables(STT) that monitor unit setting by every distance of moving collimator, was induced by numerical formular. The characteristics of dynamic wedge by STT compared with real dosimetry. Methods and Materials : The accelerator CLINAC 2100C/D at Yonsei Cancer Center has two photon energies (6MV and 10MV), currently with dynamic wedge angles of 15$^{\circ}$, 30$^{\circ}$, 45$^{\circ}$ and 60$^{\circ}$. The segmented treatment tables(STT) that drive the collimator in concert with a changing monitor unit are unique for field sizes ranging from 4.0cm to 20.0cm in 0.5cm steps. Transmission wedge factors were measured for each STT with an standard ion chamber. Isodose profiles, isodose curves, percentage depth dose for dynamic wedge filters were measured with film dosimetry. Dynamic wedge angle by STT was well coincident with film dosimetry. Percent depth doses were found to be closer to open field but more shallow than hard wedge filter. The wedge transmission factor were decreased by increased the wedge angle and more higher than hard wedge filters. Dynamic wedging probided more consistent gradients across the field compared with hard wedge filters. Dynamic wedging has practical and dosimetric advantages over hard filters for rapid setup and keeping from table collisions. Dynamic wedge filters are positive replacement for hard filters and introduction of dynamic conformal radiotherapy and intensity modulation radiotherapy in a future.