• 제목/요약/키워드: Envelope

검색결과 1,547건 처리시간 0.032초

Missile Autopilot Design for Agile Turn Control During Boost-Phase

  • Ryu, Sun-Mee;Won, Dae-Yeon;Lee, Chang-Hun;Tahk, Min-Jea
    • International Journal of Aeronautical and Space Sciences
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    • 제12권4호
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    • pp.365-370
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    • 2011
  • This paper presents the air-to-air missile autopilot design for a $180^{\circ}$ heading reversal maneuver during boost-phase. The missile's dynamics are linearized at a set of operating points for which angle of attack controllers are designed to cover an extended flight envelope. Then, angle of attack controllers are designed for this set of points, utilizing a pole-placement approach. The controllers' gains in the proposed configuration are computed from aerodynamic coefficients and design parameters in order to satisfy designer-chosen criteria. These design parameters are the closed-loop frequency, damping ratio, and time constant; these represent the characteristics of the control system. To cope with highly nonlinear and rapidly time varying dynamics during boost-phase, the global gain-scheduled controller is obtained by interpolating the controllers' gains over variations of the angle of attack, Mach number, and center of gravity. Simulation results show that the proposed autopilot design provides satisfactory performance and possesses good [ed: or "sufficient" or "excellent"] capabilities.

Ultrastructural Study of Oogenesis and Reproductive Cycle of the Female Manila Clam, Ruditapes philippinarum in Komso Bay, Korea

  • Chung, Ee-Yung;Lee, C-Hang-Hoon;Park, Ki-Ho
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 한국발생생물학회 2001년도 전기 제11차 학술대회 논문집
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    • pp.46-49
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    • 2001
  • R. Philippinarum is dioecious and oviparous. In the early vitellogenic oocyte, the Golgi apparatus and mitochondria present in the perinuclear region are involved in the formation of lipid droplets and in lipid granule formation. In the late vitellogenic oocyte, the endoplasmic reticulum, mitochondria in the cytoplasm are involved in the formation of proteid yolk granules. At this time, exogenous lipid granular substance and glycogen particles in the germinal epithelium are passed into the ooplasm of oocyte through the microvilli of the vitelline envelope. Ripe oocytes are about 55-60 $\mu$ m in diameter. The spawning period was once a year between early June and early October, and the main spawning occurred between July and August when seawater temperature was approximately 20 C. The reproductive cycle of this species can be categorized into five successive stages: early active stage (February to March), late active stage (April to May), ripe stage (April to August), partially spawned stage (June to October), and spent/inactive stage (August to March). Gonad developmental phases by histological qualitative analysis showed similar results with those of quantitative image analysis.

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Ultrastructural Studies on the Cabbage Butterfly, Pieris rapae L. II. Ovarian Development and Oogenesis (배추흰나비 (Pieris rapae L.)의 미세구조에 관한 연구 II. 난소(卵巢)의 발생(發生)과 난성숙(卵成熟))

  • Kim, C.W.;Kim, W.K.;Kim, J.H.
    • Applied Microscopy
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    • 제15권1호
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    • pp.86-100
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    • 1985
  • A observation of the ovarian development and oogenesis of Pieris rapae Linne has been carried out during metamorphosis using stereo-microscope, light microscope and electron microscope. The results obtained through this experiment are as follows: 1. The ovarian development and vitellogenesis begin at the 3-day old pupa and the 6-day old pupa respectively, and the adult ovary right after their emergence contains a few mature eggs. 2. The species described above are further observed at six different stages in oogenesis, and the results are summarized as follows. 1) Pieris rapae has polytrophic ovarioles. The cell organelles of the nurse cells are transfered to the oocyte through the ring canal at the early oogenesis. 2) At stage 2, the nuclear envelope of oocyte nucleus is less infolding than that of nurse cell nucleus. In the oocyte cytoplasm a large number of ribosomes are observed. 3) At stage 3 and 4, many micropinocytotic vesicles are observed in the oocyte cytoplasm. These vesicles are fused together to form large proteid yolks. 4) At stage 5, the vitelline membrane is laid down in the intercellular space between the follicle cells and oocyte. 5) At stage 6, the chorion is formed by the follicle cells. 6) A micropyle and a number of aeropyle are observed on the surface of a mature egg.

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Detoxification Effect of Aqua-Acupuncture aginst the Toxicity of Aconitine on the Liver of Rats (흰쥐의 간에 미치는 부자독성에 대한 약침의 해독효과)

  • Kim, Jeong-Sang;NA, Chang-Su
    • Applied Microscopy
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    • 제27권3호
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    • pp.243-255
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    • 1997
  • To investigate detoxification effects of aqua-acupuncture; Bovis Calculus and Susi Fei extract against the toxicity of aconitine were studied. We examined the GOT activities, GPT activities, $\gamma-GPT$ activites, ALP activities and ultrastructural changes of hepatocytes in rats. The GOT activities were decreased in the aqua-acupuncture group compared with control at the 48-hours and 96-hours. The $\gamma-GTP$ and ALP activities were decreased in the aqua-acpuncture group compared with control at 96-hours. We observed the ultrastructural changes of hepatocytes compared the detoxification effects of acua-acupuncture with toxicity of aconitine by transmission electron microscope. In the 24-hours group, the cisternae of rough and smooth endoplasmic reticulum hepatocytes are dilated more or less. In the 48-hours group, the nuclear envelope are irregured, and chromatins of nucleus are condensed. The cisternae of rough endoplasmic reticulum are dilated/branched. In the 96-hours group, the rough and smooth endoplasmic reticulum are well developed in aqua-acpuncture group compared with control. These results suggest that acua-acpuncture groups of the Bovis calculus and Susi fei extract showed detoxification effects against cytotoxicity of aconitine in the hepatocyte of rats.

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Ultrastructural Study of Drosophila Ocellar Visual System by Osmium Impregnation (오스뮴침착법에 의한 초파리 단안시각계의 미세구조)

  • Yoon, Chun-Sik
    • Applied Microscopy
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    • 제29권4호
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    • pp.451-457
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    • 1999
  • Ultrastructure of adult Drosophila ocellus was compared with conventional electron microscopic method and osmium impregnation. When osmium impregnation was applied, some organelles of cells were strongly stained. Especially, subrhabdomeric cisternae (SRC) were strongly stained and showed network-iike structure as in compound eye. Other organelles including SSC, ER, nuclear envelope, pigment granules and mitochondria were also strongly stained. These organelles are known as a general calcium ion reservoir. In conclusion, the strong effect of light and shade by osmium impregnation was regarded as a result of strong binding between calcium ion and osmium tetroxide. Thus, we agree to the opinion that osmium impregnation is very useful methods to the comparative morphology of cell organelles.

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Surgical Treatment of Olecranon Fractures

  • Koh, Kyoung-Hwan;Oh, Hyoung-Keun
    • Clinics in Shoulder and Elbow
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    • 제20권1호
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    • pp.49-56
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    • 2017
  • Since the olecranon fractures are caused by relatively low-energy injuries, such as a fall from standing height, they are usually found without comminution. Less commonly they can be developed by high-energy injuries and have severe concomitant comminution or injuries to surrounding structures of the elbow. Because the fracture by nature is intra-articular with the exception of some avulsion-type fracture, a majority of olecranon fractures are usually indicated for surgical treatment. Even if there is minimal displacement, surgical treatment is recommended because there is a possibility of further displacement by the traction force of triceps tendon. The most common type of olecranon fracture is displaced, simple non-comminuted fracture (that is, Mayo type IIA fractures). Although tension band wiring was the most widespread treatment method for these fractures previously, there is some trends toward fixation using locking plates. Primary goal of the surgery is to restore a congruent joint and extensor mechanisms by accurate reduction and stable fixation so that range of motion exercises can be performed. The literature has shown that good clinical outcomes are achieved irrespective of surgical fixation technique. However, since the soft tissue envelope around the elbow is poor and the implants are located at the subcutaneous layer, implant irritation is still the most common complication associated with surgical treatment.

The Differentiation of the Female Gonial Cell in Echiuroid (Urechis unicinctus): A Fine Structural Study (개불(Urechis unicinctus) 자성생식세포의 분화과정에 관한 미세구조연구)

  • Choe, Rim-Soon;Shin, Kil-Sang;Joo, Chung-No;Hwang, Dae-Yeon
    • Applied Microscopy
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    • 제18권1호
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    • pp.77-91
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    • 1988
  • Since the Urechis unicinctus-oocyte grows asynchronously in the body fluid, various oocytes in developmental stages can be prepared from each individual. The oocytes obtained from the coelomic fluid are then classified into five developmental stages according to the fine structural features. The earlier oocytes (${\sim}18{\mu}m$) form cluster and thereafter the oocytes grow singly without a distinct support of somatic cell, such as accessory cell or matrix cell. The yolk granules begin to appear already in the oocyte of cluster stage, however, the typical yolk was observed at the stage IV. Therefore, it was suggested that the yolk deposition is correlated with the coelomic fluid. The mature oocyte measured about $150{\mu}m$ produces the invagination not only on oolemma(indentation) but also on nuclear envelope. After the formation of the indentation, the mature ooytes are stored in storge sacs. The fine structural features were combined in aspect of structural concept of light microscopical observation.

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Production and Characterization of Monoclonal Antibodies to Porcine Zona Pellucida (돼지난자 투명대의 단일클론 항체 생산 및 특성화)

  • 이광희;이홍준;이상호
    • Journal of Embryo Transfer
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    • 제11권1호
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    • pp.71-80
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    • 1996
  • The envelope of the rnannnalian oocyte plays crucial roles in sperm-oocyte interactions by providing sperm receptors, inducing acrosome reaction and preventing polyspermy. Understanding of properties of the zona pellucida (ZP) is essential for the artificial control of fertility in mammals. This study was carried out to produce and characterize monoclonal antibodies(MAbs) to porcine ZP proteins. Approximately 8,000 ZPs were obtained from follicular oocytes and dissolved in 40$\mu$l of double distilled water. Following immunization through foot-pad injections of Balb /c mice with a ZP solution, the popliteal lymph nodes were recovered at 2 weeks after the last injection. Hybridoma cell lines were established by fusing lymph node cells with P3X63 myeloma cells through selection using HAT medium and screening by immunofluorescence(IF) microscopy on the isolated ZP. Secreted MAbs were found to consist k chains and different heavy chains as evidenced by isotyping. Some of the MAbs demonstrated high specificity to the ZP in IF. The Mabs also showed positive cross reactivity with hamster and mouse eggs, while negative with bovine eggs. The results implicate that the MAbs can be used not only for identification of functional regions of the ZP, but also for elucidation of mechanisms involved in fertilization of mammals. The MAbs will provide basic information on biochemical anatomy of the ZP as well as can be candidates for the future contraceptive vaccines.

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Acoustic Signal based Optimal Route Selection Problem: Performance Comparison of Multi-Attribute Decision Making methods

  • Borkar, Prashant;Sarode, M.V.;Malik, L. G.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권2호
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    • pp.647-669
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    • 2016
  • Multiple attribute for decision making including user preference will increase the complexity of route selection process. Various approaches have been proposed to solve the optimal route selection problem. In this paper, multi attribute decision making (MADM) algorithms such as Simple Additive Weighting (SAW), Weighted Product Method (WPM), Analytic Hierarchy Process (AHP) method and Total Order Preference by Similarity to the Ideal Solution (TOPSIS) methods have been proposed for acoustic signature based optimal route selection to facilitate user with better quality of service. The traffic density state conditions (very low, low, below medium, medium, above medium, high and very high) on the road segment is the occurrence and mixture weightings of traffic noise signals (Tyre, Engine, Air Turbulence, Exhaust, and Honks etc) is considered as one of the attribute in decision making process. The short-term spectral envelope features of the cumulative acoustic signals are extracted using Mel-Frequency Cepstral Coefficients (MFCC) and Adaptive Neuro-Fuzzy Classifier (ANFC) is used to model seven traffic density states. Simple point method and AHP has been used for calculation of weights of decision parameters. Numerical results show that WPM, AHP and TOPSIS provide similar performance.

OBSERVATIONS OF $HC_3N$ TOWARD THE SGR B2 MOLECULAR CLOUD

  • MINH Y. C.;KIM HYUN-GOO
    • Journal of The Korean Astronomical Society
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    • 제31권2호
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    • pp.117-125
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    • 1998
  • We have observed the 10-9 transitions of $HC_3N$ and its $^{13}C$ substitutes ($H^{13}CCCN,\;HC^{13}CCN$, and $HCC^{13}CN$), and the vibration ally excited 12-11 ($v_r=1$) $HC_3N$ transition toward the Sgr B2 molecular cloud. The observed $HC_3N$ emission shows an elongated shape around the Principal Cloud ($\~$4.5 pc in R.A. $\times$ 7.4 pc in Decl.). The optically thin $H^{13}CCCN$ line peaks around the (N) core and we derive the total column density $N(H^{13}CCCN) = 4 {\times}10^{13} cm^{-2}$ at this position. Toward the 2' N cloud which shows the peculiar chemistry, the $HC_3N$ lines show enhancements compared to the extended envelope. The shocks of the 2' N may have resulted in the enhancement of $HC_3N$. The hot component of $HC_3N$ is strongly concentrated around the (N) core and its HPW is $\~$0.9 pc in diameter. We derive the lower limit of the abundance ratio $N(HC_3N)/N(H^{13}CCCN)$ to be larger than 40 in most regions except the (M) and (N) cores. The fractionation processes of $^{13}C $at this region may not be as effective as previously reported.

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