• Title/Summary/Keyword: Stabilization control

Search Result 1,253, Processing Time 0.03 seconds

Management of Nutrient Solution Based on $\textrm{NH}_4\textrm{H}_2\textrm{PO}_4$Concentration in Deep Flow Culture of Cherry Tomato (방울토마토 담액재배시 $\textrm{NH}_4\textrm{H}_2\textrm{PO}_4$ 농도에 기초한 배양액 조절)

  • 이문정;김성은;김영식
    • Journal of Bio-Environment Control
    • /
    • v.4 no.2
    • /
    • pp.188-194
    • /
    • 1995
  • This study was carried out to investigate the effect of NH$_4$H$_2$PO$_4$ on pH stabilization in deep flow culture system using tap water, and to determine the optimum range of NH$_4$H$_2$PO$_4$ in culture solution. The pH of tap water is 7.5. The higher the concentration of NH$_4$H$_2$PO$_4$ was, the more the pH of nutrient solution was decreased. In NH$_4$H$_2$PO$_4$ 4/3-5/3 me/$\ell$, the pH of nutrient solution was 6-7.5 during the experiment. The highest brix(%) was obtained in NH$_4$H$_2$PO$_4$ 5/3-6/3 me/$\ell$. Leaf length, leaf width and stem-base diameter were highest in NH$_4$H$_2$PO$_4$ 2/3 me/$\ell$. The L and b* values were highest and the a* value was lowest in NH$_4$H$_2$PO$_4$ 8/3 me/$\ell$. Toxicity symptom of ammonium appeared in NH$_4$H$_2$PO$_4$ 8/3 me/$\ell$. It suggests that there was the relationship between leaf color and growth condition. It was concluded that NH$_4$H$_2$PO$_4$ 2/3 me/$\ell$ was good before harvest stage and NH$_4$H$_2$PO$_4$ 5/3-6/3 me/$\ell$ at harvest stage.

  • PDF

A Study to Improve the Performance of a Fixd Type Fin Stabilizer with Coanda Effect (콴다효과를 적용한 고정식 핀 안정기의 성능개선에 관한 연구)

  • Seo, Dae-Won;Lee, Se-Jin;Lee, Seung-Hee
    • Journal of Navigation and Port Research
    • /
    • v.37 no.3
    • /
    • pp.257-262
    • /
    • 2013
  • A ship operating in rough sea may suffer from an undesirable motion which may severely degrade the performance of equipment onboard and give a person an uncomfortable feeling. Hence, roll stabilization received a considerable attention and various devices including bilge keels, stabilizing fins, gyroscopic, anti-rolling tanks, rudders and flaps have been conceived and utilized for the purpose. The Coanda effect is evident when a jet stream is applied tangential to a curved surface of a hydrofoil since then the jet increases the circulation around the foil and consequently the lift. Model tests and numerical simulation have been conducted to examine the practicality of a fixed type fin stabilizer augmented by the Coanda jet. The results show that the lift coefficient of the modified Coanda fin at the zero angle of attack identically coincides with that of the original fin at ${\alpha}=\26^{\circ}$ when Coanda jet is supplied at the rate of $C_j$ = 0.25. It is also shown that fixed type fin stabilizers for active control of the motions of ships and the other mobile units without rotation can be put to practical use if the Coanda effect is applied.

DESIGN AND IMPLEMENTATION OF HITL SIMULATOR COUPLEING COMMUNICATIONS PAYLOAD AND SOFTWARE SPACECRAFT BUS (통신탑재체와 소프트웨어 위성버스체를 통합한 HITL 시뮬레이터의 설계 및 구현)

  • 김인준;최완식
    • Journal of Astronomy and Space Sciences
    • /
    • v.20 no.4
    • /
    • pp.339-350
    • /
    • 2003
  • Engineering qualification model payload for a communications and broadcasting satellite(CBS) was developed by ETRI from May, 2000 to April, 2003. For. the purpose of functional test and verification of the payload, a real-time hardware-in-the-loop(HITL) CBS simulator(CBSSIM) was also developed. We assumed that the spacecraft platform for the CBSSIM is a geostationary communication satellite using momentum bias three-axis stabilization control technique based on Koreasat. The payload hardware is combined with CBSSIM via Power, Command and Telemetry System(PCTS) of Electrical Ground Support Equipment(EGSE). CBSSIM is connected with PCTS by TCP/IP and the payload is combined with PCTS by MIL-STD-1553B protocol and DC harness. This simulator runs under the PC-based simulation environment with Windows 2000 operating system. The satellite commands from the operators are transferred to the payload or bus subsystem models through the real-time process block in the simulator. Design requirements of the CBSSIM are to operate in real-time and generate telemetry. CBSSIM provides various graphic monitoring interfaces and control functions and supports both pre-launch and after-launch of a communication satellite system. In this paper, the HITL simulator system including CBSSIM, communications payload and PCTS as the medium of interface between CBSSIM and communications payload will be described in aspects of the system architecture, spacecraft models, and simulator operation environment.

Development of Machine Learning-Based Platform for Distillation Column (증류탑을 위한 머신러닝 기반 플랫폼 개발)

  • Oh, Kwang Cheol;Kwon, Hyukwon;Roh, Jiwon;Choi, Yeongryeol;Park, Hyundo;Cho, Hyungtae;Kim, Junghwan
    • Korean Chemical Engineering Research
    • /
    • v.58 no.4
    • /
    • pp.565-572
    • /
    • 2020
  • This study developed a software platform using machine learning of artificial intelligence to optimize the distillation column system. The distillation column is representative and core process in the petrochemical industry. Process stabilization is difficult due to various operating conditions and continuous process characteristics, and differences in process efficiency occur depending on operator skill. The process control based on the theoretical simulation was used to overcome this problem, but it has a limitation which it can't apply to complex processes and real-time systems. This study aims to develop an empirical simulation model based on machine learning and to suggest an optimal process operation method. The development of empirical simulations involves collecting big data from the actual process, feature extraction through data mining, and representative algorithm for the chemical process. Finally, the platform for the distillation column was developed with verification through a developed model and field tests. Through the developed platform, it is possible to predict the operating parameters and provided optimal operating conditions to achieve efficient process control. This study is the basic study applying the artificial intelligence machine learning technique for the chemical process. After application on a wide variety of processes and it can be utilized to the cornerstone of the smart factory of the industry 4.0.

The Usefulness of Airway Tube Merocel® on Treatment of Nasal Bone Fracture (비골골절치료에서 기도 튜브 머로셀®의 유용성)

  • Jung, Yun Joo;Choi, Young Woong;Nam, Sang Hyun;Yoon, Gil Young
    • Archives of Craniofacial Surgery
    • /
    • v.10 no.1
    • /
    • pp.14-18
    • /
    • 2009
  • Purpose: Nasal packing materials are almost inserted at the end stage of closed reduction of nasal bone for postoperative bleeding control and stabilization of nasal bone. Conventionally, vaseline gauze was used for packing of nasal cavity. These days, Surgeons have tried to apply $Merocel^{(R)}$ into the nasal cavity more easily. It is difficult for patients to continue keeping the nasal packs for more than a week due to breathing difficulty. Moreover, nasal packing itself can also cause headache, dry mouth, stuffiness, etc. Methods: We performed a prospective study from March 1, 2008 to July 31, 2008. One hundred patients were divided into "$Merocel^{(R)}$ packing group" and "$Merocel^{(R)}$ and Airway Tube $Merocel^{(R)}$ packing group". Using two kinds of materials to each group after closed reduction, we observed and compared the amount of bleeding between two groups. We recorded patient's uncomfortable symptoms which were divided into four groups each 6, 24, 48 hours after nasal packing. Results: The result of the bleeding amount of Air Tube $Merocel^{(R)}$ group after 6 hours of nasal packing is that 3 people belong to mild group, 38 people moderate group, and 9 people severe group. After 6 hours of nasal packing, 11 patients have no complains. 16 patients were mild, 21 patients were moderate, 2 patients were severe. After 24 hours of nasal packing, no complain(18 patients), mild(24 patients), moderate(6 patients), severe(0 patient). After 48 hours of nasal packing, no complain(25 patients), mild(20 patients), moderate(5 patients), severe(0 patient). Conclusion: Regarding the amount of bleeding, there are no difference between two groups. In case of Air Tube $Merocel^{(R)}$ group, patient's discomfort is gradually improved after 24 hours of nasal packing, After 48 hours of nasal packing, most of the patients do not experience headache, dry mouth, stuffiness, etc. Therefore, Air Tube $Merocel^{(R)}$ can be useful for bleeding control. Moreover, it helps patients to breathe through nose more easily and reduce discomfort.

Stabilization of Membrane Proteins by Benzyladenine during Wheat Leaf Senescence (노쇠중인 밀잎에서 Benzyladenine에 의한 막단백질의 안정화)

  • 진창덕
    • Journal of Plant Biology
    • /
    • v.35 no.2
    • /
    • pp.117-123
    • /
    • 1992
  • The effect of benzyladenine (BA) on lipid peroxidation and compositions of total insoluble proteins and chloroplast thylakoid protein from wheat primary leaves during senescence in the dark was studied. BA ($10^{-5}\;M$) treatment prevented conspicuously the loss of chlorophyll content and soluble and insoluble leaf protein contents in senescing wheat leaf segments during 4-day dark incubation. Under the BA treatment, especially, the level of insoluble protein was highly maintained than that of soluble protein. Also, the increase of malondialdehyde (MDA: the peroxidation product of membrane lipids) content was inhibited in the BA treated leaves. Three major polypeptide bands in quantity corresponding to 57, 26 and 12 KD molecular weight were clearly resolved with other minor bands by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) in the insoluble protein fraction. The insoluble protein profiles of the control leaves showed a remarkable decrease in the intensity of the 57 and 12 KD band except for 26 KD band in the 72 h dark incubation. This loss during dark incubation was reduced by BA treatment. More than 20 polypeptides were resolved in the chloroplast thylakoid membrane fraction with the most prominent bands which are 59 and 57 KD ($\alpha\;and\;\beta$ subunit of coupling factor: CF) and 26 KD (apoprotein of LHCP). The changes in thylakoid protein profile during 72 h dark incubation showed the rapid degradation in control, but this degradation was prevented in quantity by BA treatment. The above results suggested that BA would inhibit the peroxidation of membrane lipids, thereby preventing the loss of membrane proteins which led to the maintenance of the membrane integrity including chloroplast thylakoid.

  • PDF

Development of the Small Scale Testbed for Running Dynamic Characteristics Analysis of the Capsule Train (캡슐트레인 주행 동특성 분석을 위한 축소 시험장치의 개발)

  • Lee, Jin-Ho;You, Won-Hee;Lee, Kwansup
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.9
    • /
    • pp.643-651
    • /
    • 2020
  • A capsule train runs inside a sub-vacuum tube and can reach very high speed due to the low air resistance. A capsule train uses a superconducting electrodynamic suspension (SC-EDS) method for levitation, which allows for a large levitation gap and does not require gap control. However, SC-EDS has inherent characteristics such as the large gap variation and a small damping effect in the levitation force, which can degrade the running stability and ride comfort. To overcome this, a stability improvement device should be designed and applied based on dynamic analysis. In this study, a 1/10 small-scale testbed was developed to replicate the dynamic characteristics of a capsule train and investigate the performance of stability improvement devices. The testbed is composed of a 6-degree-of-freedom Stewart platform for the realization of bogie motion, a secondary suspension with a running stabilization device, and a carbody. Based on the dynamic similarity law proposed by Jaschinski, the small-scale testbed was manufactured, and a bogie motion algorithm was applied with the consideration of guideway irregularity and levitation stiffness. The experimental results from the testbed were compared with simulation results to investigate the performance of the testbed.

Determinant Factors for Expenditure of the Medical Insurance Program for Self-Employeds (지역의료보험(地域醫療保險) 재정지출(財政支出)의 결정요인(決定要因))

  • Kam, Sin;Park, Jae-Yong;Yeh, Min-Hae
    • Journal of Preventive Medicine and Public Health
    • /
    • v.28 no.1 s.49
    • /
    • pp.153-174
    • /
    • 1995
  • This study was conducted to examine the determinant factors for expenditure of the medical insurance program for self-employeds based on the analysis of 1991 'The Medical Insurance Program for Self-Employeds Statistical Yearbook', and also similar yearbooks in the metropolitan and other provinces. The major findings are as follows : We have divided benefits into these four components such as the utilization rate for out-patients, expenses per claim for out-patients as paid by the insurer, utilization rate for in-patients, and the expenses per claim for in-patients as paid by the insurer, in order to examine the determinant factors for it. The results of the study revealed the following findings, in urban areas, the supply of medical care had more influence on the benefits than other demographic and economic variables, while, in county areas, both the supply of medical care and the rate of those aged over 65 affected the provision of benefits. The determinant factors for financial balance of the medical insurance program for self-employeds are, first, the determinant factor for administrative expenses was the number of households. The more the number of households, the less the administrative expenses per the insured. This shows that the economy of scale is being. And so, the administrative district must be taken into consideration in the incorporation of small regional medical societies and should be re-organized for more efficient management. Second, in urban areas, the supply of medical care had more influence on utilization rate and expenses per claim as paid by insurer, and therefore it is necessary to control it. In county areas, the supply of medical care and the rate of those aged over 65 raised the utilization rate and expenses per claim as paid by insurer. For the financial stability of county areas, a common fund for medical care for the aged and expansion of finance stabilization fund would be necessary. But, in county areas, it would be unnecessary to control the supply of medical care because it was much more insufficient than in urban areas. The vitalization of public health facilities must be carried out in county areas, for they reduced benefits. Sice the more insured in a single household, the less the utilization of the medical insurance program, benefits for habilitation at home should be given consideration. The law of majority and the economy of scale were applied here, and therefore the incorporation of regional medical societies must be taken into consideration. In integrating regional medical societies, it would be absolutely necessary to review the structural differences among all regional medical societies, the medical demand of each region, and also the local characteristics of each region.

  • PDF

A Study on the Effectiveness of Inter-temporal Reallocation of Fiscal Expenditure in Korea (재정지출의 시점 간 재원배분 조정에 따른 경기조절 효과성에 관한 연구)

  • Kim, SeongTae;Hur, Seok-Kyun
    • KDI Journal of Economic Policy
    • /
    • v.35 no.2
    • /
    • pp.71-105
    • /
    • 2013
  • Now that fiscal soundness is increasingly important influenced by the euro area fiscal crisis, early budget execution has been under the spotlight as a tool for economy control, other than typical expansionary method, such as supplementary budget. Basically, early budget execution is a fiscal policy instrument that reponses to economic fluctuations through modifying the inter-temporal allocation of fiscal expenditure within budget, without affecting fiscal soundness. This study empirically examines how effective the intert-temporal reallocation of fiscal expenditure is in economy control. Using Korea's Consolidated Fiscal data, the size of inter-temporal reallocation of fiscal expenditure is defined as changes of fiscal expenditure for one year excluding seasonal factors and used to explain real economic growth rate, a dependent variable. The result shows that the macroeconomic effect of the inter-temporal reallocation turns out meaningful in general, though some policy time lag exists. Meanwhile, a simulation using macroeconomic model finds that overall effect on economic growth is not large because increase in fiscal expenditure allocation at a certain point of time is canceled by the opposite direction within the same fiscal year. However, the inter-temporal reallocation is found to reduce volatility of key macroeconomic variables so as to contribute to partially stabilizing macroeconomy. In particular, such effect of economic stabilization seems to be highly apparent at the time of financial crisis, but not very noticeable in normal economic cycle.

  • PDF

The Research on the Development Steps and Facing Problems of Korean and Japanese Laver Industry (한일 김산업의 발전과정 분석과 당면과제 연구)

  • Ock, Young-Soo
    • The Journal of Fisheries Business Administration
    • /
    • v.42 no.2
    • /
    • pp.113-130
    • /
    • 2011
  • The laver has been cultivated long time ago by Korea and Japan. Korean Laver Industry has been influenced by Japan on the many factors since 20th. Nevertheless now the both country showed widening disparities across the aspect of total Laver Industry each other. The development steps of Korea and Japan Laver Industry have been advanced differently. That is, we can keep the Laver Industry development steps of both countries separate by 4 steps. But insignificant of every step against both countries has been dissimilar. We can separate from 4 steps in Korea, 1 step is origin period from beginning of laver cultivation to 1961. Next step is First Development period from 1962 to 1978. This period come out production increase from about 10,000 tons early 1960 to 50,000 tons late 1970. Next step is Second Development period from 1979 to 2000. This period come out eminent production increase from about 50,000 tons early 1980 to 200,000 tons late 1990. Next step is Stabilization period from 2001 to now. This period come out production control the size of its production and enlargement of Laver Export. We can also separate from 4 steps in Japan, 1 step is origin period from beginning of laver cultivation to 1944. Next step is Development period from 1945 to 1975. This period come out production increase from about 4 billion sheets early 1960 to 8.5 billion sheets 1975. Next step is Peak period from 1976 to 1982. This period come out sustainable production peak by 6~8 billion sheets and high price. Next step is Decline period from 1983 to now. This period come out production control the size of its production and sustainable price down. These differences showed out facing problems of Korean and Japanese Laver Industry differently. In case of Korea, the facing problems show out 3. First is structural problem, for example, trouble between original laver producer and the finished producer by dry laver products. Second is Insufficiency of Plants Protection System. Third is low quality of Laver. In case of Japan, the facing problems also show out 3. First is sustainable decrease of laver consumption. Second is change of mind against laver, for example, the change of the propensity to consume, and decrease of brand power. Third is Influence of global system. The difference of development steps of Korea and Japan Laver Industry show out 2 point of view to us. First we need consider positive strategy against laver production system of enlargement. Second, we need consider separate strategy against high quality laver and low quality laver.