• Journal of the Korean Operations Research and Management Science Society
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• v.17 no.1
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• pp.127-134
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• 1992

In this paper, we first examine the stochastic behavior associated with storage/retrieval process under COL policy, and give analytical results such as the limiting distributions of the number of items in the system and the expected travel distance. We also investigate the phenomenon of natural zoning, that is, the tendency of similar items to group themselves together, when two types of items with different turnover rates are stored and retrieved. Natural zoning refers to this grouping occurring under the seemingly unbiased policy COL. We show that zoning can occur naturally with batch arrivals to the storage system.

• Journal of the Korean Mathematical Society
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• v.37 no.4
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• pp.521-530
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• 2000

We find the values of numerical invariants col(R) and row (R) for R=k[te, te+1, t(e-1)e-1] where k is a field and e$\geq$4. We also show that col(R) = crs (R) and row (R) = drs(R), but they are strictly less than the reduction number of R plus 1.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.10a
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• pp.560-563
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• 2004

본 논문은 분노, 행복, 평정, 슬픔, 놀람 둥과 같은 인간의 감정상태를 인식하는 새로운 접근에 대해 설명한다. 이러한 시도는 이산길이를 포함하는 연속 은닉 마르코프 모델(HMM)을 사용함으로써 이루어진다. 이를 위해, 우선 입력음성신호로부터 감정의 특징 파라메타를 정의 한다. 본 연구에서는 피치 신호, 에너지, 그리고 각각의 미분계수 등의 운율 파라메타를 사용하고, HMM으로 훈련과정을 거친다. 또한, 화자적응을 위해서 최대 사후확률(MAP) 추정에 기초한 감정 모델이 이용된다. 실험 결과, 음성에서의 감정 인식률은 적응 샘플수의 증가에 따라 점차적으로 증가함을 보여준다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.46
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• pp.137-146
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• 1998

Most studies related to AS/RS are about operation policies or system designs. However, the studies on operation policy could not deal with various products using the single unit load system. In this paper, two different sized units are introduced and six different AS/RS operation policies are developed to process the different sized items. Computer simulation is used to evaluate AS/RS performances on various operation policies and to find the most effective operation policy for each case. The simulation model is developed using GPSS/PC and operation policies include COL-FIFO-SP, SIL-FIFO-SP, COL-RN-SP, COL-FIFO-LP, SIL-FIFO-LP and COL-RN-LP. The policies are evaluated based on the criteria of crane utilization, rack utilization, crane moving time, throughput and waiting time.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.391-393
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• 2007

The rotor speed and flux information is most important in the vector control. The accuracy of flux observers for induction machine inherently depends on parameter sensitivity. The control strategy is using online flux observer for flux estimation. In the proposed system, the speed control characteristics using a online flux observer control isn't affected by a load torque parameter disturbance. Simulation results are presented to prove the effectiveness of the adaptive sliding mode controller for the drive variable load of induction motor.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.415-417
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• 2007

In this paper, The authors study the boost Regulator as a DC-DC Converter like a power supply and describe the investigation result about the two phase with combined boost regulator which has the same effect that the switching frequency of the solid-state-switch is two times. As a result, the ripple of the input current and output current is better improved.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.441-443
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• 2007

In this paper, The authors design the current controller which independently control the d, q axis current transformed by the synchronously rotating d, q axis and a Space Vector Pulse Width Modulation(SVPWM) to steadily control the output DC-Link voltage against the variable load of the three phase PWM converter. Also, This study improves the high power factor, stability, and rapid response by the phase angle control using the digital Phase Locked Loop(PLL).

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.335-339
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• 2003

The aim of this study is to optimize the monolayer cultivation of human articular chondrocytes in serum-free media. For this purpose, chondrocytes were isolated from human articular cartilage and monolayer cultures were performed in DMEM/F12 medium with 10% fetal bovine serum (FBS) or serum-free media (SFM) containing various supplements and epidermal growth factor (EGF). Western blotting analysis, RT-PCR, dimethylmethylene blue (DMB) assay were carried out to evaluate the synthesis of collagen type II (Col. II) and glycosaminoglycans (GAGs). We observed that SFM with EGF stimulated the cell growth while the amounts of synthesized GAGs and Col. II were decreased gradually. However, the Col. II mRNA level was increased when the SFM was replaced by media containing 10% FBS. This study suggests that it is possible to obtain large amount of human articular chondrocytes by short-term monolayer cultures in SFM.

• Journal of Microbiology and Biotechnology
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• v.32 no.7
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• pp.938-948
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• 2022

Gastric cancers (GC) are generally malignant tumors, occurring with high incidence and threatening public health around the world. Circular RNAs (circRNAs) play crucial roles in modulating various cancers, including GC. However, the functions of circRNAs and their regulatory mechanism in colorectal cancer (CRC) remain largely unknown. This study focuses on both the role of circCOL1A2 in CRC progression as well as its downstream molecular mechanism. Quantitative polymerase chain reaction (qPCR) and western blot were adopted for gene expression analysis. Functional experiments were performed to study the biological functions. Fluorescence in situ hybridization (FISH) and subcellular fraction assays were employed to detect the subcellular distribution. Luciferase reporter, RNA-binding protein immunoprecipitation (RIP), co-immunoprecipitation (Co-IP), RNA pull-down, and immunofluorescence (IF) and immunoprecipitation (IP) assays were used to explore the underlying mechanisms. Our results found circCOL1A2 to be not only upregulated in GC cells, but that it also propels the migration and invasion of GC cells. CircCOL1A2 functions as a competing endogenous RNA (ceRNA) by sequestering microRNA-1286 (miR-1286) to modulate ubiquitin-specific peptidase 10 (USP10), which in turn spurs the migration and invasion of GC cells by regulating RFC2. In sum, CircCOL1A2 sponges miR-1286 to promote cell invasion and migration of GC by elevating the expression of USP10 to downregulate the level of RFC2 ubiquitination. Our study offers a potential novel target for the early diagnosis and treatment of GC.

• The korean journal of orthodontics
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• v.28 no.6 s.71
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• pp.915-926
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• 1998

The cytoskeleton has been shown to form a network, connecting the extracelluar matrix via integrin with the nucleus and the cytoplasmic constituents of the cell. It is therefore assumed that the cytoskeleton may mediate signals generated by perturbations originating in the matrix. The purpose of this study is to examine the effect of cytoskeletal change on osteoblastic cell activities. The author cultured osteoblastic cells obtained from neonatal mouse calvaria. The cells were teated with cytochalasin B(CB) or colchicine (COL) at four concentrations for 3 hours and after another 24 hours the conditioned media was collected and assayed for prostaglandin $E_2\;(PGE_2)$, interleukin-6(IL-6), tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and matrix metalloproteinase-1(MMP-1). In addition, the cytoskeletal protein actin were observed by immuno-fluorescence. The results were as follows: 1. The production of $PGE_2$ showed the tendency to be increased in CB-treated group. $PGE_2$ was increased in COL-treated group dose-dependantly, 2. IL-6 production, in CB-treated group, was increased, except at 1.0 ${\mu}g/ml$. IL-6 was induced in COL-treated group. 3. TNF-$\alpha$ production was increased in CB-treated group, except at 1.0 ${\mu}g/ml$, and in COL-treated group, that was increased. 4. The MMP-1 production was decreased in CB-treated soup and was not changed in COL-treated group, which could be selectively visualized by immunoblotting with monospecific antibody. 5. The cytoskeletal actin stress fibers were disappeared and the cells showed to be rounded in CB-treated group. These results indicated that there are a relationship between the cytoskeletal rearrangements and osteoblastic cell activities, especially in release of paracrine/autocrine factors, such as $PGE_2$, IL-6, and TNF-$\alpha$.