• Journal of Ginseng Research
• /
• 제47권2호
• /
• pp.349-351
• /
• 2023

• Journal of Positioning, Navigation, and Timing
• /
• 제11권3호
• /
• pp.199-208
• /
• 2022

Inertial Navigation System (INS)/Global Navigation Satellite System (GNSS) integrated navigation system can be used for land vehicle navigation. When the GNSS signal is blocked in a dense urban area or tunnel, however, the problem of increasing the error over time is unavoidable because navigation must be performed only with the INS. In this paper, Non-Holonomic Constraints (NHC) information is utilized to solve this problem. The NHC may correct some of the errors of the INS. However, it should be noted that NHC information is not applicable to all areas within the vehicle. In other words, the lever arm effect occurs according to the distance between the Inertial Measurement Unit (IMU) mounting position and the NHC effective point, which causes the NHC condition not to be satisfied at the IMU mounting position. In this paper, an INS/GNSS/NHC integrated navigation filter is designed, and this filter has a function to compensate for the lever arm effect. Therefore, NHC information can be safely used regardless of the vehicle's driving environment. The performance of the proposed technology is verified through Monte-Carlo simulation, and the performance is confirmed through experimental test.

• 한국군사과학기술학회지
• /
• 제12권5호
• /
• pp.636-643
• /
• 2009

NHC means that the velocity of the vehicle in the plane perpendicular to the forward direction is almost zero. The main error source of NHC is the mounting misalignment which is the difference between the body frame of a land vehicle and the sensor frame of an inertial measurement unit. This paper suggests new NHC algorithm that can reduce position errors by real-time estimation of mounting misalignment. Then NHC/ZUPT integrated land navigation system is designed and its performances are analyzed by simulations with van test data. Simulation results show that the proposed NHC/ZUPT land navigation system improves navigation accuracy regardless of misalignment angle and is very useful when SDINS operates stand-alone for land vehicle navigation with large mounting misalignment.

• Bulletin of the Korean Chemical Society
• /
• 제31권5호
• /
• pp.1143-1148
• /
• 2010

We investigated the separation of nitrogen heterocyclic compound (NHC) contained in a model coal tar fraction comprising four kinds of NHC [indole (In), quinoline (Q), iso-quinoline (iQ), quinaldine (Qu)], three kinds of bicyclic aromatic compound (BAC) [1-methylnaphthalene (1MN), 2-methylnaphthalene (2MN), dimethylnaphthalene (DMN) mixture with ten structural isomers (DMNs; regarded as one component)], biphenyl (Bp) and phenyl ether (Pe) by liquid membrane permeation (LMP). A batch-stirred tank was used as the permeation unit. An aqueous solution of saponin and n-hexane were used as the liquid membrane and the outer oil phase, respectively. Yield and selectivity of individual NHC was much larger than that of BAC, Bp and Pe. Increasing the initial mass fraction of the saponin to the membrane solution ($C_{sap,0}$) and the initial volume fraction of O/W emulsion to total liquid in a stirred tank (${\phi}_{OW,0}$) resulted in deteriorating the yield of individual NHC, but increasing the stirring speed (N) resulted in improving the yield of each NHC. With increasing $C_{sap,0}$, the selectivity of each NHC based on DMNs increased. Increasing ${\phi}_{OW,0}$ and N resulted in decreasing the selectivity of individual NHC based on DMNs. At an experimental condition fixed, the sequence of the yield and selectivity in reference to DMNs for each NHC was Q > Qu = iQ > In. Furthermore, we compared LPM method with methanol extraction method in view of the separation efficiency (yield, selectivity) of NHC.

• 공업화학
• /
• 제26권2호
• /
• pp.234-238
• /
• 2015

모델 콜타르 유분 중에 함유된 질소고리화합물(NHC)의 분리를 메탄올과 포름아마이드 추출에 의해 비교했다. 원료로서는 4종류의 NHC (NHCs : 퀴놀린, 이소퀴놀린, 인돌, 퀴날딘), 3종류의 2환 방향족 화합물(BACs : 1-메틸나프탈렌, 2-메틸나프탈렌, 디메틸나프탈렌), 비페닐과 페닐에테르로 제조한 모델 콜타르 유분을 사용했다. 용매로서는 메탄올과 포름아마이드 수용액을 사용했다. 원료와 용매의 접촉 장치로서는 회분 교반기를 사용했다. 사용한 용매와 무관하게, 초기 용매 함수율의 감소와 평형조작 온도의 상승은 NHCs의 분배계수를 급격히 증가시켰으나, 역으로 BACs를 기준한 NHCs의 선택도를 감소시켰다. 초기 용매/원료의 체적비가 감소함에 따라 NHCs의 분배계수는 감소했으나, BACs를 기준한 NHCs의 선택도는 거의 일정했다. 동일한 실험조건에서, NHCs의 분배계수는 메탄올 추출이 포름아마이드 추출에 비해 약 3~5배 높았으나, BACs를 기준한 NHCs의 선택도는 역으로 포름아마이드 추출이 메탄올 추출에 비해 3~7배 높았다. 또한, NHCs의 용해력과 선택도의 밸런스에 NHCs의 추출처리속도를 부가하여 두 용매 추출법을 비교했다.

• Journal of Ginseng Research
• /
• 제46권3호
• /
• pp.426-434
• /
• 2022

Aim: This study investigates the effects of ginsenoside Rb1 (GsRb1) on methamphetamine (METH)-induced toxicity in SH-SY5Y neuroblastoma cells and METH-induced conditioned place preference (CPP) in adult Sprague-Dawley rats. It also examines whether GsRb1 can regulate these effects through the NR2B/ERK/CREB/BDNF signaling pathways. Methods: SH-SY5Y cells were pretreated with GsRb1 (20 mM and 40 mM) for 1 h, followed by METH treatment (2 mM) for 24 h. Rats were treated with METH (2 mg/kg) or saline on alternating days for 10 days to allow CPP to be examined. GsRb1 (5, 10, and 20 mg/kg) was injected intraperitoneally 1 h before METH or saline. Western blot was used to examine the protein expression of NR2B, ERK, P-ERK, CREB, P-CREB, and BDNF in the SH-SY5Y cells and the rats' hippocampus, nucleus accumbens (NAc), and prefrontal cortex (PFC). Results: METH dose-dependently reduced the viability of SH-SY5Y cells. Pretreatment of cells with 40 µM of GsRb1 increased cell viability and reduced the expression of METH-induced NR2B, p-ERK, p-CREB and BDNF. GsRb1 also attenuated the expression of METH CPP in a dose-dependent manner in rats. Further, GsRb1 dose-dependently reduced the expression of METH-induced NR2B, p-ERK, p-CREB, and BDNF in the PFC, hippocampus, and NAc of rats. Conclusion: GsRb1 regulated METH-induced neurotoxicity in vitro and METH-induced CPP through the NR2B/ERK/CREB/BDNF regulatory pathway. GsRb1 could be a therapeutic target for treating METH-induced neurotoxicity or METH addiction.

• 공업화학
• /
• 제25권2호
• /
• pp.142-146
• /
• 2014

9성분계 모델 콜타르 유분 중에 함유된 질소고리화합물(NHC)의 분리를 분배평형에 의해 검토했다. 원료로서는 NHC group (NHCs; quinoline (Q), iso-quinoline (iQ), indole (In), quinaldine(Qu)), 2환 방향족 화합물 group (BACs; 1-methylnaphthalene (1MN), 2-methylnaphthalene (2MN), dimethylnaphthalene (DMN)), biphenyl (Bp)과 phenyl ether (Pe)로 제조한 모델 콜타르 유분을, 용매로서는 메탄올 수용액을 각각 사용했다. 액-액 접촉 장치로서는 회분 교반기를 각각 사용했다. 평형조작 온도가 상승함에 따라 NHCs의 분배계수는 증가했으나, 역으로 BACs를 기준한 NHCs의 선택도는 감소했다. 초기 물/용매의 체적비가 감소함에 따라 BACs를 기준한 NHCs의 선택도는 급격히 감소했으나, NHCs의 분배계수는 증가했다. 일정 조건하에서, 각 group별 분배계수와 BACs를 선택도의 순서는 NHCs > Bp > BACs > Pe와 NHCs > Bp > Pe를 각각 나타냈다. 또한 전체 성분에 대한 분배계수의 순서는 In > iQ = Q > Qu > Bp > 1MN = 2MN > Pe > DMN을 나타냈다. 메탄올 추출에 의해 얻어진 NHCs의 최대 수율과 BACs를 기준한 NHCs의 최대 선택도는 각각 94%, 23이었다. 본 연구를 통해 얻어진 실험적 결과를 이용하여 콜타르 중에 함유된 NHCs의 회수공정을 검토했다.

• Journal of Positioning, Navigation, and Timing
• /
• 제11권1호
• /
• pp.29-34
• /
• 2022

In this paper, we analyze the Non-Holonomic Constraint (NHC) satisfaction of Inertial Navigation System (INS) for vehicular navigation according to Inertial Measurement Unit (IMU) location. In INS-based vehicle navigation, NHC information is widely used to improve INS performance. That is, the error of the INS can be compensated under the condition that the velocity in the body coordinate system of the vehicle occurs only in the forward direction. In this case, the condition that the vehicle's wheels do not slip and the vehicle rotates with the center of the IMU must be satisfied. However, the rotation of the vehicle is rotated by the steering wheel which is controlled based on the Ackermann geometry, where the center of rotation of the vehicle exists outside the vehicle. Due to this, a phenomenon occurs that the NHC is not satisfied depending on the mounting position of the IMU. In this paper, we analyze this problem based on Ackermann geometry and prove the analysis result based on simulation.

• Journal of Positioning, Navigation, and Timing
• /
• 제10권3호
• /
• pp.179-187
• /
• 2021

To estimate the location of the train, we consider an integrated navigation system that combines Inertial Navigation System (INS) and Global Navigation Satellite System (GNSS). This system provides accurate navigation results in open sky by combining only the advantages of both systems. However, since measurement update cannot be performed in GNSS signal blocked areas such as tunnels, mountain, and urban areas, pure INS is used. The error of navigation information increases in this area. In order to reduce this problem, the train's Non-Holonomic Constraints (NHC) information can be used. Therefore, we deal with the INS/GNSS/NHC integrated navigation system in this paper. However, in the process of installing the navigation system on the train, a Mounting Misalignment Error of the IMU (MMEI) inevitably occurs. In this case, if the NHC is used without correcting the error, the navigation error becomes even larger. To solve this problem, a method of easily estimating the MMEI without an external device is introduced. The navigation filter is designed using the Extended Kalman Filter (EKF) by considering the MMEI. It is assumed that there is no vertical misalignment error, so only the horizontal misalignment error is considered. The performance of the integrated navigation system according to the presence or absence of the MMEI and the estimation performance of the MMEI according to the method of using NHC information are analyzed based on simulation. As a result, it is confirmed that the MMEI is accurately estimated by using the NHC information together with the GNSS information, and the performance and reliability of the integrated navigation system are improved.

• Bulletin of the Korean Chemical Society
• /
• 제32권spc8호
• /
• pp.2881-2882
• /
• 2011