• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.1189-1192
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• 2005

Due to their slow degradation properties, hydrophobic organic contaminants in estuarine sediment have been a concern for risks to human health and aquatic organisms. Studies of fate and transport of these contaminants in estuaries are further complicated by the fact that hydrodynamics and sediment transport processes in these regions are complex, involving processes with various temporal and spatial scales. In order to simulate and quantify long-term attenuation of Polycyclic Aromatic Hydrocarbons (PAH) in the Elizabeth River, VA, we develop a modeling approach, which employs the U.S. Environmental Protection Agency's water quality model, WASP, and encompasses key physical and chemical processes that govern long-term fate and transport of PAHs in the river. In this box-model configuration, freshwater inflows mix with ocean saline water and tidally averaged dispersion coefficients are obtained by calibration using measured salinity data. Sediment core field data is used to estimate the net deposition/erosion rate, treating only either the gross resuspension or deposition rate as the calibration parameter. Once calibrated, the model simulates fate and transport PAHs following the loading input to the river in 1967, nearly 4 decades ago. Sediment PAH concentrations are simulated over 1967-2022 and model results for Year 2002 are compared with field data measured at various locations of the river during that year. Sediment concentrations for Year 2012 and 2022 are also projected for various remedial actions. Since all the model parameters are based on empirical field data, model predictions should reflect responses based on the assumptions that have been governing the fate and sediment transport for the past decades.

• 원예과학기술지
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• 제35권2호
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• pp.199-209
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• 2017

This study detailed the effects of 1-methylcyclopropene (1-MCP) on ripening and fruit quality in red-fleshed kiwifruit (Actinidia chinensis) stored at 0 or $10^{\circ}C$ for 20 days, and $20^{\circ}C$ for 13 days. The quality of the fruit was assessed by measuring ethylene production, respiration rate, weight loss, firmness, flesh color, soluble solids content (SSC), and titratable acidity (TA), along with a sensory evaluation. Compared to untreated kiwifruit, fruit treated with $1{\mu}L{\cdot}L^{-1}$ 1-MCP for 24h at $20^{\circ}C$ prior to storage showed a delay in ripening and maintained fruit quality during storage. Ethylene production and respiration rate were affected by 1-MCP treatment only in fruit stored at $20^{\circ}C$, where the values were markedly higher compared to kiwifruit stored at 0 and $10^{\circ}C$. 1-MCP treatment resulted in a clear reduction in weight loss due to a delay in fruit ripening. The firmness of kiwifruit stored at 10 and $20^{\circ}C$ decreased significantly compared to fruit stored at $0^{\circ}C$, but 1-MCP treatment led to a reduction in this loss. Upon storage, SSC increased while TA decreased across all treatments. Sensory evaluation scores increased with decreasing firmness and acidity and increasing SSC. The shelf life of kiwifruit stored at $0^{\circ}C$ was extended without any chilling injury or color changes. In summary, the results show that 1-MCP treatment can potentially maintain quality and delay ripening of red-fleshed kiwifruit stored at all storage temperatures.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.1067-1072
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• 2013

Hiwi, a human homologue of the Piwi family, plays an important role in stem cell self-renewal and is overexpressed in various human tumors. This study aimed to determine whether an RNA interference-based strategy to suppress Hiwi expression could inhibit tumor growth in a xenograft mouse model. A rare population of $SSC^{lo}\;Alde^{br}$ cells was isolated and identified as lung cancer stem cells in our previous study. Plasmids containing U6 promoter-driven shRNAs against Hiwi or control plasmids were successfully established. The xenograft tumor model was generated by subcutaneously inoculating with lung cancer stem cell $SSC^{lo}\;Alde^{br}$ cells. After the tumor size reached about 8 mm in diameter, shRNA plasmids were injected into the mice via the tail vein three times a week for two weeks, then xenograft tumor growth was assessed. In nude mice, intravenously delivery of Hiwi shRNA plasmids significantly inhibited tumor growth compared to treatment with control scrambled shRNA plasmids or the vehicle PBS. No mice died during the experiment and no adverse events were observed in mice administered the plasmids. Moreover, delivery of Hiwi shRNA plasmids resulted in a significant suppressed expression of Hiwi and ALDH-1 in xenograft tumor samples, based on immunohistochemical analysis. Thus, shRNA-mediated Hiwi gene silencing in lung cancer stem cells by an effective in vivo gene delivery strategy appeared to be an effective therapeutic approach for lung cancer, and may provide some useful clues for RNAi gene therapy in solid cancers.

• 한국통신학회논문지
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• 제27권11C호
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• pp.1152-1157
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• 2002

본 논문에서는 voice gateway응용에서 널리 사용되어지는 AAL2 프로세서의 구현과정에 대해 기술하였다. 본 프로세서는 음성과 프레임 모드 데이터를 서비스하기 위한 CPS와 SSCS를 지원한다. 또한 4개의 ATM 가상연결을 지원하며, 그 연결은 총 1020개의 AAL2채널을 포함한다. ATM 셀 인터페이스로 UTOPIA Level 1을 사용하고, 음성 채널 인터페이스로 4개의 TDM포트를 갖고 있다. TDM포트에는 PCM과 ADPCM데이터가 존재한다. 대부분의 AAL2프로세서들은 소프트웨어로 구현되어 있거나 또는 소프트웨어와 하드웨어의 혼합으로 되어 있다. 그러므로 데이터를 처리하는데 어느 정도의 지연이 있게 된다. 그러나 본 논문의 프로세서는 하드웨어로 구현되어 있기 때문에 CPS와 SSCS에 대해 매우 적은 처리지연을 보이고 있다. 또한, CPS 패킷들의 루프백과 스위칭이 가능하게 구현되었고, TDM채널에 대해서도 역시 스위칭과 루프백이 가능하도록 구현되었다. 구현된 프로세서의 특징은 CPS와 SSCS의 so부 구조가 소프트웨어의 함수를 보는 듯하다는 것이다. 또한 그 블록을 포함하는 다른 블록들을 설계 시 재사용되어 질 수 있으며, 대용량의 채널을 수용할 때에도 응용 가치가 높다고 사료된다.

• Agricultural and Biosystems Engineering
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• 제1권2호
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• pp.81-87
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• 2000

Quality characteristics of tomatoes irradiated with light (red light of far-red light followed two days later with a red light treatment), treated with ethylene, and stored in darkness were evaluated by subjective sensory and objective physical and chemical evaluations. Overall and individual liking evaluations and sensory evaluations were made by an untrained panel of eighteen people. A rankin gof treatments for consumer (panelist) acceptability was also conducted by the panel. Physical and chemical evaluations included surface color measurement (L*, a*, and b*), mechanical puncturing (firmness), soluble solids content (SSC), titratable acidity(TA), and tomato juice pH. Sensory data showed that outside color, inside color, and flavor of tomatoes treated with red light (R) and far-red light/red light (FR/R) were scored significantly higher than those of tomatoes treated with ethylene and those kept in darkness. The L* values for tomatoes treated with R and FR/R were lower (more darkening) than those for tomatoes treated with ethylene and those stored in darkness. Tomatoes treated with FR/R had the highest A* values, followed by those irradiated with R, treated with ethylene, and kept in darkness, respectively. Sensory values for firmness were similar for tomatoes treated with R, FR/R, and ethylene. Treatments had no significantly different effects on sweetness and acidity. There were no significantly different effects between treatments for pH, SSC, TA, and SSC/TA. From observations made during the study, it was suggested that R irradiation stimulated red color development in tomatoes after it had been delayed by FR irradiation. Consumer acceptability for tomatoes with either R or FR/R treatment was significantly higher than that for tomatoes treated with ethylene or stored in darkness. panelists' overall liking scores correlated well with all sensory variables except acidity, and also correlated highly with inside color, flavor, and sweetness (P<0.001). Overall liking versus flavor had the most pronounced relationship (r=0.78, P<0.001).

• Nuclear Engineering and Technology
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• 제43권1호
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• pp.63-74
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• 2011

The 600 MWe, pool-type, sodium-cooled, metallic fuel loaded KALIMER-600 (Korea Advanced LiquId MEtal Reactor, 600 MWe) has been conceptually designed with an emphasis on safety by self-regulating (inherent/intrinsic) negative reactivity feedback in the core. Its inherent safety under the ATWS (Anticipated Transient Without Scram) events was demonstrated in an earlier study. Initiating events of an HCDA (Hypothetical Core Disruptive Accident), however, also need to be analyzed for assessment of the margins in the current design. In this study, a hypothetical triple-fault accident, ULOF (Unprotected Loss Of Flow) with a reduced pump halving time, is investigated as an initiator of a core disruptive accident. A ULOF with insufficient primary pump inertia may cause core sodium boiling due to a power-to-flow mismatch. If the positive sodium reactivity resulting from this boiling is not compensated for by other intrinsic negative reactivity feedbacks, the resulting core power burst would challenge the fuel integrity. The present study focuses on determination of the limit of the pump inertia for assuring inherent reactivity feedback and behavior of the core after sodium boiling as well. Transient analyses are performed with the safety analysis code SSC-K, which now incorporates a new sodium boiling model. The results show that a halving time of more than 6.0 s does not allow sodium boiling even with very conservative assumptions. Boiling takes place for a halving time of 1.8 s, and its behavior can be predicted reasonably by the SSC-K.

• 한국자원식물학회지
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• 제27권6호
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• pp.701-706
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• 2014

Three highbush blueberries (Vaccinium corymbosum cvs. Bluecrop, Coville, and Northland) grown in an open field and in a rain shelter were compared to evaluate the potential benefits of rain-sheltering systems on growth and fruit quality. Shrubs grown in rain shelter flowered 5-14 days earlier and were in full bloom earlier than those in the open field. All three cultivars set fruit by nearly 90% of flowers when they were grown in the open field, but was markedly reduced when they were grown in the rain shelter, to approximately 50% for 'Bluecrop' and 'Coville'. Fruit sets ratio of 'Northland' grown in the in the rain shelter was 14.5. Fruit from greenhouse-grown 'Northland' were larger, heavier, and had more seeds per berry. Soluble sugar content (SSC) of fruits varied both with the cultivars and growing conditions. SSC of fruits grown in the greenhouse was higher in 'Bluecrop' compared to that grown in the field, but this pattern was reversed in 'Northland'. Titratable acid was significantly higher in fruits from rain shelter-grown shrubs of both 'Bluecrop' and 'Northland' than in fruits from open field-grown shrubs (P < 0.05), although there was no difference in TA with respect to growing conditions for 'Coville'. The number of seed per fruit, fruit length and diameter, weight, SSC, and TA were similar in 'Coville' shrubs grown in the open field and the rain shelter. Fruit firmness of 'Bluecrop', 'Coville', and 'Northland' was higher in the rain shelter than in the open field. 'Coville' and 'Northland' fruits harvested in the open field had higher blue chroma than those harvested in the rain shelter. However, this pattern was reversed for 'Bluecrop'. On the whole, sheltering from rain affected most fruit characteristics of the three cultivars differently. Therefore, suitable blueberry cultivars for the rain shelter should be chosen by purpose.

• 한국정밀공학회지
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• 제30권1호
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• pp.39-46
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• 2013

Smart material such as SMA (Shape Memory Alloy) has been studied in various ways because it can perform continuous, flexible, and complex actuation in simple structure. Smart soft composite (SSC) was developed to achieve large deformation of smart material. In this paper, a shell actuator using woven type SSC was developed to enhance stiffness of the structure while keeping its deformation capacity. The fabricated actuator consisted of a flexible polymer and woven structure which contains SMA wires and glass fibers. The actuator showed various actuation motions by controlling a pattern of applied electricity because the SMA wires are embedded in the structure as fibers. To verify the actuation ability, we measured its maximum end-edge bending angle, twisting angle, and actuating force, which were $103^{\circ}$, $10^{\circ}$, and 0.15 N, respectively.

• Tuberculosis and Respiratory Diseases
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• 제82권4호
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• pp.285-297
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• 2019

Connective tissue disease (CTD) is a collection of disorders characterized by various signs and symptoms such as circulation of autoantibodies in the entire system causing damage to internal organs. Interstitial lung disease (ILD) which is associated with CTD is referred to as CTD-ILD. Patients diagnosed with ILD should be thoroughly examined for the cooccurrence of CTD, since the treatment procedures and prognosis of CTD-ILD are vary from those of idiopathic interstitial pneumonia. The representative types of CTD which may accompany ILD include rheumatoid arthritis, systemic sclerosis (SSc), Sjogren's syndrome, mixed CTD, idiopathic inflammatory myopathies, and systemic lupus erythematous. Of these, ILD most frequently co-exists with SSc. If an ILD is observed in the chest, high resolution computed tomography and specific diagnostic criteria for any type of CTD are met, then a diagnosis of CTD-ILD is made. It is challenging to conduct a properly designed randomized study on CTD-ILD, due to low incidence. Therefore, CTD-ILD treatment approach is yet to been established in absence of randomized controlled clinical trials, with the exception of SSc-ILD. When a patient is presented with acute CTD-ILD or if symptoms occur due to progression of the disease, steroid and immunosuppressive therapy are generally considered.

• Steel and Composite Structures
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• 제49권6호
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• pp.615-631
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• 2023

To investigate the seismic behavior of steel slag self-stressing concrete-filled circular steel tubular (SSSCFCST) columns, 14 specimens were designed, namely, 10 SSSCFCST columns and four ordinary steel slag (SS) concrete (SSC)-filled circular steel tubular (SSCFCST) columns. Comparative tests were conducted under low reversed cyclic loading considering various parameters, such as the axial compression ratio, diameter-thickness ratio, shear-span ratio, and expansion ratio of SSC. The failure process of the specimens was observed, and hysteretic and skeleton curves were obtained. Next, the influence of these parameters on the hysteretic behavior of the SSSCFCST columns was analyzed. The self stress of SS considerably increased the bearing capacity and ductility of the specimens. Results indicated that specimens with a shear-span ratio of 1.83 exhibited compression bending failure, whereas those with shear-span ratios of 0.91 or 1.37 exhibited drum-shaped cracking failure. However, shear-bond failure occurred in the nonloading direction. The stiffness of the falling section of the specimens decreased with increasing shear-span ratio. The hysteretic curves exhibited a weak pinch phenomenon, and their shapes evolved from a full shuttle shape to a bow shape during loading. The skeleton curves of the specimens were nearly complete, progressing through elastic, elastoplastic, and plastic stages. Based on the experimental study and considering the effects of the SSC expansion rate, shear-span ratio, diameter-thickness ratio, and axial compression ratio on the seismic behavior, a peak displacement coefficient of 0.91 was introduced through regression analysis. A simplified method for calculating load-displacement skeleton curves was proposed and loading and unloading rules for SSSCFCST columns were provided. The load-displacement restorative force model of the specimens was established. These findings can serve as a guide for further research and practical application of SSSCFCST columns.