• The Journal of the Acoustical Society of Korea
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• 제13권1E호
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• pp.11-19
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• 1994

상태 지속 밀도를 사용하는 hidden Markov Models(HMM/SD)은 음성 신호의 시간적인 변화를 보다 명확하게 나타낼 수 있다 그러나 상태 지속 밀도가 완만하거나 제한된 상태가 길면 이러한 장점은 감소된다. 이러한 문제점을 해결하기 위하여, 본 논문에서는 상태간의 천이가 특정한 시간 구간에서만 발생하도록 하는 전에 경로 제한 조건을 갖는 HMM/GPC를 제한한다. HMM/GPC는 상태 지속을 제한하고 음성 신호의 시간적 변화를 단순하고 효과적으로 표현할 수 있다. 또한 HMM/SD와 HMM/GPC를 결합한 새로운 형태의 HMM/SD+GPC를 제안하고 성능을 비교하였다. HMM/GPC는 기존 Viterbi 알고리즘을 약간 수정하여 구현될 수 있다. HMM/GPC와 HMM/SD+GPC는 기존 HMM과 HMM/SD에 비하여 우수한 성능을 보일 뿐만아니라 계산량도 매우 작다. 화자도립 단독음 인식 실험에서, HMM/GPC(1.6%)의 최소 오차는 기존 HMM보다 1.1% 낮았고 계산량도 57% 감소하였다.

• 한국정보통신학회논문지
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• 제7권7호
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• pp.1527-1532
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• 2003

기존의 GPC방법으로 제어하기 힘든 비선형성과 플랜트의 변수변화를 포함하는 비선형 플랜트를 지연 예측신경망을 사용하여 효과적으로 제어하는 적응 GPC방법을 제안한다 제안한 방법에서는 플랜트의 선형 변수 추정이나 근사적인 모델로부터 선형 매개변수를 구해서 선형 모델을 만들고 실제 시스템의 출력과 선형모델의 오차를 신경망의 출력으로 표현한 다음, 이 식으로부터 적응 GPC 알고리듬을 유도한다. 여기서 지연 예측신경망은 적응 GPC에 이용될 플랜트의 출력을 예측하도록 학습된다. 이와 같은 제어기를 구성함으로써 선형 변수만으로 적응 GPC 제어기가 구성되어질 경우 생기는 비선형 변수의 추정과 출력 예측 값을 계산하는 번거로움을 해결하였다.

• 미생물학회지
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• 제34권3호
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• pp.91-95
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• 1998

한우의 반추위액에서 섬유소를 분해하는 균주 GPC-1, GPC-2, GNR-1, GNR-2, GNR-3를 선별하였다. 분리주 GPC-1과 GPC-2는 Gram 양성구균이며 편성혐기균으로서 Ruminococcus속으로 분류되었다. 분리주 GNR-1, GNR-2 및 GNR-3는 Gram 음성 간균이며 혐기균으로서 내생포자형성 유무에 따라 포자 형성균인 GNR-3는 Clostridium속으로 분류하고 포자를 형성하지 않은 균은 $H_2S$ 생성유무에 따라 Bacteroides 속과 Butyrivibrio 속으로 분류되었다. 종수준의 동정을 위하여 당분해능과 생화학적 조사를 통하여 GPC-1는 Ruminococcus albus로, GPC-2는 Ruminococcus flavefaciens로, GNR-1는 Bacteroides succinogenes로, GNR-2는 Butyrivibrio fibrisolvens로, GNR-3는 Clostridium cellobioparum로 각각 동정하였다.

• Advances in concrete construction
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• 제5권4호
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• pp.345-358
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• 2017

This paper describes the experimental investigation carried out to develop geopolymer concrete using rice husk ash (RHA) along with alccofine. The study reports the fresh and hardened properties of the geopolymer concrete (GPC) activated using alkaline solution. GPC were prepared using different RHA content (350, 375 and $400kg/m^3$), the molarity of the NaOH (8, 12 and 16M). The specimens were cured at $27^{\circ}C$ and $90^{\circ}C$. GPC was activated using NaOH, $Na_2SiO_3$, and alccofine. Prepared GPC samples were tested for compressive and splitting tensile strengths after 3, 7 and 28 days. RHA was suitable to produce geopolymer concrete. Results indicate that behavior of GPC prepared with RHA is similar to fly ash based GPC. Workability and strength can be improved by incorporating the alccofine. Further, alccofine and heat curing improve the early age properties of the GPC. Heat curing is responsible for the initial polymerization of GPC which leads to high workability and improved mechanical properties of the GPC. High strength can be achieved by using the high concentration alkaline solution in terms of molarity and at elevated heat curing. Further, RHA based geopolymer concrete has tremendous potential as a substitute for ordinary concrete.

• The Korean Journal of Physiology and Pharmacology
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• 제25권4호
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• pp.333-339
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• 2021

Injection lipolysis or mesotherapy gained popularity for local fat dissolve as an alternative to surgical liposuction. Phosphatidylcholine (PPC) and aminophyl-line (AMPL) are commonly used compounds for mesotherapy, but their efficacy and safety as lipolytic agents have been controversial. Glycerophosphocholine (GPC) is a choline precursor structurally similar to PPC, and thus introduced in aesthetics as an alternative for PPC. This study aimed to evaluate the effects of GPC on adipocytes differentiation and lipolysis and compared those effects with PPC and AMPL using in vitro and in vivo models. Adipogenesis in 3T3-L1 was measured by Oil Red O staining. Lipolysis was assessed by measuring the amount of glycerol released in the culture media. To evaluate the lipolytic activity of GPC on a physiological condition, GPC was subcutaneously injected to one side of inguinal fat pads for 3 days. Lipolytic activity of GPC was assessed by hematoxylin and eosin staining in adipose tissue. GPC significantly suppressed adipocyte differentiation of 3T3-L1 in a concentration-dependent manner (22.3% inhibition at 4 mM of GPC compared to control). Moreover, when lipolysis was assessed by glycerol release in 3T3-L1 adipocytes, 6 mM of GPC stimulated glycerol release by two-fold over control. Subcutaneous injection of GPC into the inguinal fat pad of mice significantly reduced the mass of fat pad and the size of adipocytes of injected site, and these effects of GPC were more prominent over PPC and AMPL. Taken together, these results suggest that GPC is the potential therapeutic agent as a local fat reducer.

• Molecules and Cells
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• 제21권2호
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• pp.224-228
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• 2006

Glypican-3 (GPC3) is a member of the glypican family, which encodes cell-surface heparan-sulfate proteoglycans, and is frequently upregulated in hepatocellular carcinoma (HCC). We have recently reported that blocking endogenous GPC3 expression promotes the growth of HCC cell lines, suggesting that GPC3 plays a negative role in HCC cell proliferation. Here, we report that forced expression of GPC3 reduced the growth of HCC cells. We also found that FGF2-mediated cell proliferation was inhibited by GPC3. In addition, we observed that the adhesion of HCC cells to collagen type I and fibronectin was decreased by GPC3, whereas cellular migration and invasiveness were stimulated. Collectively, these results suggest that progression of hepatocellular carcinoma is associated with upregulation of GPC3.

• Advances in concrete construction
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• 제14권5호
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• pp.331-339
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• 2022

Geopolymer concrete (GPC) is one of the best substitute materials for conventional concrete in construction. The conventional concrete provided by Portland cement has a detrimental influence on the environment during its production. In this study, the bond strength, which is an important structural property, of deformed steel bars with slag-based GPC was measured. In accordance with the ASTM C234 procedure, bond strength was measured on 18 specimens of slag-based GPC with three sizes of steel bars and different embedded lengths. Two groups of GPC specimens with different compressive strengths, which were cured under ambient conditions, were tested. The results indicated that the bar diameter has a great effect on the bond strength, and the bond strength behavior of the slag-based GPC is comparable with that of conventional concrete. The ACI-318 Code for the bond strength of ordinary Portland cement concrete can be used conservatively to determine the bond strength of the GPC reinforced with deformed steel bars.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.965-969
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• 1993

In this paper, the GPC algorithm is developed for ACS(advanced control system). ACS equals to DCS(distributed control system) with some advanced control algorithm, for example, fuzzy logic controller, autotuning. By its embedded structural control language, which uses simple function codes corresponding to each function blocks, it is possible to construct multiloop controller. The developed GPC function code is divided by RLS (recursive least square) parameter estimator and GPC controller. Simulation result show the availability of GPC function code using the control language.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.176-181
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• 1992

In this paper, an adaptive generalized predictive control(GPC) algorithm which minimizes a N-stage cost function is proposed. The resulting controller is based on GPC algorithm and can be used in unknown plant parameters as the parameters of one step ahead predictor are estimated by recursive least squares method. The estimated parameters are extended to G,P, and F amtrix which contain the parameters of N step ahead predictors. And the minimization of cost function assuming no constraints on future controls results in the projected control increment vector. Hence this adaptive GPC algorithm can be used for either unknown system or varing system parameters, and it is also shown through simulations that the algorithm is robust to the variation of system parameters. This adaptive GPC scheme is shown to have the same stability properties as the deterministic GPC, and requires small amount of calculation compared to other adaptive algorithms which minimize N-stage cost function. Especially, in case that the maximum output horizon is 1, the proposed algorithm can be applicable to direct adaptive GPC.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.49-55
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• 1992

In this paper, we developed a Receding Horizon Predictive Control for Stochastic state space models(RHPCS). RHPCS was designed to minimize a quadratic cost function. RHPCS consists of Receding Horizon Tracking Control(RHTC) and a state observer. It was shown that RHPCS is equivalent to Generalized Predictive Control(GPC) when the underlying state space model is equivalent to the I/O model used in the design of GPC. The equivalence between GPC and RHPCS was shown through. the comparison of the transfer functions of the two controllers. RHPCS provides a time-invarient optimal control law for systems for which GPC can not be used. The stability properties of RHPCS was derived. From the GPC's equivalence to RHPCS, the stability properties of GPC were shown to be the same as those for RHTC.