• Title/Summary/Keyword: 4WS

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Stability Control of Four-Wheel Steering Vehicles (4WS 차량의 안정성 제어)

  • Ko, Young-Eun;Song, Chul-Ki
    • Transactions of the Korean Society of Automotive Engineers
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    • v.16 no.3
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    • pp.127-136
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    • 2008
  • Vehicle stability is a very important subject in vehicle design and control, because vehicle safety is closely dependent upon its dynamic stability. The control logic for four-wheel steering(4WS) systems, in which maintaining at least the specified stability region is the control objective, was constructed using the simplified vehicle model of 3 degree-of-freedoms. The improvement of vehicle stability was verified through computer simulations for the slalom and the double lane change maneuver using the multi-body dynamic model in MSC.ADAMS.

A Study on Lateral Stability Enhancement of 4WS Vehicle with Active Front Wheel Steer System (능동전륜조향장치를 채택한 사륜조향차량의 횡방향 안정성 강화에 대한 연구)

  • Song, Jeong-Hoon
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.2
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    • pp.15-20
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    • 2012
  • This study is to propose and develop an integrated dynamics control system to improve and enhance the lateral stability and handling performance. To achieve this target, we integrate an AFS and a 4WS systems with a fuzzy logic controller. The IDCS determines active additional steering angle of front wheel and controls the steering angle of rear wheel. The results show that the IDCS improves the lateral stability and controllability on dry asphalt and snow paved road when double lane change and step steering inputs are applied. Yaw rate of the IDCS vehicle tracks reference yaw rate very well and body slip angle is reduced about by 50%. Response time of the IDCS vehicle is also decreased.

Integrated Monitoring System for Business Process Management based on BPEL4WS (BPEL4WS 기반의 비즈니스 프로세스 관리를 위한 통합 모니터링 시스템)

  • 이종혁;국윤규;김운용;최영근
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.10a
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    • pp.52-54
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    • 2004
  • BPEL4WS는 이기종의 시스템을 사용하는 사내 조직뿐만 아니라 협력 업체 및 고객 전반에 걸쳐 비즈니스 프로세스를 통합해준다 통합된 비즈니스 프로세스 관리는 이질적인 수행환경 극복, 기업 간 프로세스 자동화, 프로세스에 대한 모니터링 및 관리, 비즈니스 트랜잭션 관리, 파트너 상태에 대한 관리가 필요하다. 하지만 비즈니스 프로세스, 비즈니스 트랜잭션, 파트너 상태에 대한 관리에 대한 연구가 미흡하다. 따라서 본 논문에서는 통합 프로세스 모니터링 시스템을 제안함으로서, 프로세스 관리자에게 비즈니스 진행상태에 대한 가시성을 제공하고, 신뢰성 있는 웹 서비스를 위한 트랜잭션을 관리해 주며, 예외 처리를 위한 파트너들의 모니터링 기능을 제공한다.

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The Relationship of Vegetation and Environmental Factors in Wangsuk Stream and Gwarim Reservoir: I. Water Environments

  • Lee, Bo-Ah;Kwon, Gi-Jin;Kim, Jae-Geun
    • The Korean Journal of Ecology
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    • v.28 no.6
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    • pp.365-373
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    • 2005
  • Understanding the relation of water environmental factors and vegetation is critical to restoration and management of wetlands. To reveal relationships between representative plant groups and water environments, we measured cover and abundance of plant species, water depth, temperature, pH, conductivity, dissolved oxygen, $NH_4$-N, $NO_3$-N, and $PO_4-P$ concentration in water in Wangsuk stream (WS) and Gwarim reservoir (GR). This study was conducted monthly from May to October, 2004. Six vegetation groups $(W1{\sim}W6)$ in WS and five vegetation groups $(G1{\sim}G5)$ in GR were identified using TWINSPAN. WS was characterized by Phragmites japonica, Digitaria sanguinalis, Phalaris arundinacea, Beckmannia xyzigachne and Persicara hydropiper, Persicaria thunbergii, Typha angustifolia. GR was characterized by T. angustifolia, Scirpus tabernaemontani, P. thunbergii, Humulus japonicus and Scirpus fluviatilis, Typha orientalis, Zizania latifolia. The vegetation in WS experienced greater seasonal changes than in GR. A correspondence analysis suggests that water depth was the major environmental factor influencing the distribution of most plants communities in both wetlands.

Monitoring of white striping and wooden breast cases and impacts on quality of breast meat collected from commercial broilers (Gallus gallus)

  • Malila, Yuwares;U-chupaj, Juthawut;Srimarut, Yanee;Chaiwiwattrakul, Premsak;Uengwetwanit, Tanaporn;Arayamethakorn, Sopacha;Punyapornwithaya, Veerasak;Sansamur, Chalutwan;Kirschke, Catherine P.;Huang, Liping;Tepaamorndech, Surapun;Petracci, Massimiliano;Rungrassamee, Wanilada;Visessanguan, Wonnop
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.11
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    • pp.1807-1817
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    • 2018
  • Objective: This study aimed at investigating white striping (WS) and wooden breast (WB) cases in breast meat collected from commercial broilers. Methods: A total of 183 breast samples were collected from male Ross 308 broilers slaughtered at the age of 6 weeks (n = 100) and 7 weeks (n = 83). The breasts were subjected to meat defect inspection, meat quality determination and histology evaluation. Results: Of 183, 4 breasts from 6-week-old broilers were classified as non-defective while the others exhibited the WS lesion. Among the 6-week-old birds, the defective samples from the medium size birds (carcass weight ${\leq}2.5kg$) showed mild to moderate WS degree with no altered meat quality. Some of the breasts from the 6-week-old birds with carcass weight above 2.5 kg exhibited WB in accompanied with the WS condition. Besides of a reduction of protein content, increases in collagen matter and pH values in the defective samples (p<0.05), no other impaired quality indices were detected within this group. All 7-week-old broilers yielded carcasses weighing above 2.5 kg and showed abnormal characteristics with progressive severity. The breasts affected with severe WS and WB showed the greatest cook loss, hardness, springiness and chewiness (p<0.05). Development of WB induced significantly increased drip loss in the samples (p<0.05). Histology indicated necrotic events in the defective myofibers. Based on logistic regression, increasing percent breast weight by one unit enhanced the chance of WS and WB development with advanced severity by 50.9% and 61.0%, respectively. Delayed slaughter age from 6 to 7 weeks increased the likelihood of obtaining increased WS severity by 56.3%. Conclusion: Cases of WS and WB defects in Southeast Asia have been revealed. Despite few cases of the severe WS and WB, such abnormal conditions significantly impaired technological properties and nutritional quality of broiler breasts.

Effects of Water Stress on Carotenoid and Proline Contents in Kale (Brassica oleracea var. acephala) leaves (수분스트레스가 케일 잎의 카로티노이드 및 프롤린 함량에 미치는 영향)

  • Lee, Hyo-Joon;Chun, Jin-Hyuk;Kim, Sun-Ju
    • Korean Journal of Environmental Agriculture
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    • v.36 no.2
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    • pp.97-105
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    • 2017
  • BACKGROUND : Environmental stress has a major effect on the growth and yields of vegetables, and can significantly affect nutritionally important phytochemicals, causing large economic losses. METHODS AND RESULTS : The present study was aimed at exploring the effects of water stress on the carotenoid and proline contents in kale leaves to understand drought tolerance of kale plants. Kale was randomly divided into two groups at 57 days after sowing (DAS). One of the groups was well-watered (WW) and the other was water stressed (WS). Harvesting of kale leaves was started one day after treatment (58 DAS) and continued for 10 days (~67 DAS). We investigated the status of plant growth (leaf number, length, width, fresh weight) of kale throughout the study. Carotenoid (lutein, ${\alpha}-carotene$, zeaxanthin, ${\beta}-carotene$) and proline contents were analyzed by high-performance liquid chromatography (HPLC). Our results showed that the total carotenoid contents ranged from 926.0 to 1,212.0 mg/kg dry wt. (at 3 and 2 days, respectively) in WW treatment and 887.8 to 1,157.4 mg/kg dry wt. (at 10 and 4 days, respectively) in WS treatment. The ratio of individual carotenoid to the total carotenoid contents of kale leaves was 51.4 for lutein, 4.44 for zeaxanthin, 2.76 for ${\alpha}-carotene$, and 41.4% for ${\beta}-carotene$. Total carotenoid contents showed a significant reduction from 7 days (1,037.2 mg/kg dry wt.) to 10 days (887.8 mg/kg dry wt.) in WS treatment. The lutein content did not show a significant difference in WW between 7 and 10 days after treatment but showed a significant difference in WS treatment. The ${\alpha}-carotene$ content showed no significant difference between the treatments. However, zeaxanthin content was higher during 4-10 days and ${\beta}-carotene$ content was lower during 6-10 days in WS than in WW on each harvest day. In WW, the proline content showed no significant difference, but in WS, the proline content started to increase at 7 days and almost doubled in 10 days. CONCLUSION : The marked increase in zeaxanthin and proline contents in kale leaves indicated that the two phytochemicals are associated with drought tolerance in the plant.

A Disctete Model Reference Control With a Neural Network System Ldentification for an Active Four Wheel Steering System

  • 김호용;최창환
    • Journal of the Korean Institute of Intelligent Systems
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    • v.7 no.4
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    • pp.29-39
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    • 1997
  • A discrete model reference control scheme for a vehicle four wheel steering system(4WS) is proposed and evaluated for a class of discrete time nonlinar dynamics. The schmen employs a neural network to identify the plan systems, wher the neural network estimates the nonlinear dynamics of the plant. The algorithm is proven to be globally stable, with tracking errors converging to the neighborhood of zero. The merits of this scheme is that the global system stability is guaranteed. Whith thd resulting identification model which contains the neural networks, the parameters of controller are adjusted. The proposed scheme is applied to the vehicle active four wheel system and shows the validity and effectiveness through simulation. The three-degree-of freedom vehicle handling model is used to investigate vehicle handing performances. In simulation of the J-turn maneuver, the yaw rate overshoot reduction of a typical mid-size car is improved by 30% compared to a two wheel steering system(2WS) case, resulting that the proposed scheme gives faster yaw rate response andl smaller side slip angle than the 2WS case.

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Phosphate Solubilization and Gene Expression of Phosphate-Solubilizing Bacterium Burkholderia multivorans WS-FJ9 under Different Levels of Soluble Phosphate

  • Zeng, Qingwei;Wu, Xiaoqin;Wang, Jiangchuan;Ding, Xiaolei
    • Journal of Microbiology and Biotechnology
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    • v.27 no.4
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    • pp.844-855
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    • 2017
  • Phosphate-solubilizing bacteria (PSB) have the ability to dissolve insoluble phosphate and enhance soil fertility. However, the growth and mineral phosphate solubilization of PSB could be affected by exogenous soluble phosphate and the mechanism has not been fully understood. In the present study, the growth and mineral phosphate-solubilizing characteristics of PSB strain Burkholderia multivorans WS-FJ9 were investigated at six levels of exogenous soluble phosphate (0, 0.5, 1, 5, 10, and 20 mM). The WS-FJ9 strain showed better growth at high levels of soluble phosphate. The phosphate-solubilizing activity of WS-FJ9 was reduced as the soluble phosphate concentration increased, as well as the production of pyruvic acid. Transcriptome profiling of WS-FJ9 at three levels of exogenous soluble phosphate (0, 5, and 20 mM) identified 446 differentially expressed genes, among which 44 genes were continuously up-regulated when soluble phosphate concentration was increased and 81 genes were continuously down-regulated. Some genes related to cell growth were continuously up-regulated, which would account for the better growth of WS-FJ9 at high levels of soluble phosphate. Genes involved in glucose metabolism, including glycerate kinase, 2-oxoglutarate dehydrogenase, and sugar ABC-type transporter, were continuously down-regulated, which indicates that metabolic channeling of glucose towards the phosphorylative pathway was negatively regulated by soluble phosphate. These findings represent an important first step in understanding the molecular mechanisms of soluble phosphate effects on the growth and mineral phosphate solubilization of PSB.

A Clinical Trial about Anti-anxiety and Anti-stress Effect of a modified formula consisted with Several Herbs (발아현미와 수종한약재 추출액의 스트레스 및 불안상태 개선 효과에 대한 임상연구)

  • Kim Lak Hyung;Jang In Soo;Kim Jeong Yun;Song Jeong Mo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.6
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    • pp.1533-1537
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    • 2003
  • This double-blind randomized clinical trial was performed to evaluate the anti-anxiety, anti-stress effect of a modified formula WS-01 consisted with several herbs(Jujubae Fructus. Longanae Arillus. Poria Cocos) and germinated rice. The extract of the formula was administered (p.o) to 24 students and placebo was to 23 students for 4 weeks. STAI-KYZ(Hahn. Hakjisa), ABR2000(Meridian, Korea), CBC, LFT, U/A were checked before and after the administration period. There was no difference between the STAI score of WS-01 and that of placebo group in first test. But the STAI state anxiety score was 5.33±7.33 reduced in WS-01 group and it was 0.52±6.42 increased in placebo group in second test. this result was significant stastically. 10 students in WS-01 group showed improving result, but only 1 student in placebo group showed improving result of ABR2000 test. The result of ABR2000 was analyzed with curve 2, Regulation 2, and graph 1,2,3, because those reflect central nerve system and stressful condition of the body. There was no significant result in first and second CBC, LFT, Urine test. The results of this clinical study suggest that WS-01 has anti-anxiety, anti-stress effect, and it could be applied to various conditions or disorders related with anxiety and stress.

Effect of Selective Consumption on Intake, Diet Selectivity and Passage Kinetics of Wheat Straw by Barbari Goats

  • Biswal, B.;Hasan, Q.Z.;Sharma, K.;Dutta, N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.7
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    • pp.913-917
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    • 2000
  • Sixteen adult Barbari bucks were divided into 4 homogeneous groups, each group was offered wheat straw (WS) at levels 75, 100, 125 and 150 per cent of ad libitum intake in a factorial randomized complete block design. All goats were uniformly fed a supplement ($13.5g\;DM/kg\;W^{0.75}$) to fulfill their requirement for protein at maintenance level. The experimental feeding of goats at different levels for 21 days was followed by a digestion trial of 6 days and determination of rate of passage of digesta for 144 h duration, respectively. Intake ($g/kg\;W^{0.75}$) of dry matter (DM), organic matter (OM), digestible DM and digestible OM increased with increase in amount of WS offered. The levels of WS refusals for obtaining upper limit of intake was found to be above 30% of DMO. Concentration of ADF and lignin was significantly lower and CP was higher (p>0.05) in food ingested relative to food offered or refused in response to increasing allowance of WS. Dietary means of particulate rate of passage from rumen, transit time and total mean retention time ranged from 0.032 to 0.036/h, 19.10 to 21.72/h and 58.61 to 61.53/h respectively and did not show significant differences (p>0.05) irrespective of dietary level of WS. The results suggest that DMI and quality of ingested WS would improve with higher rates of offer and refusals (${\geq}30%$ of DMO) without any pronounced effect on passage kinetics of digesta, because of the greater opportunity afforded to goats for selective feeding.