• Title/Summary/Keyword: SAC

Search Result 1,018, Processing Time 0.029 seconds

The Study of Antioxidant Effects in Melanins Extracted from Various Tissues of Animals

  • Lin, Liang-Chuan;Chen, Wei-Tai
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.18 no.2
    • /
    • pp.277-281
    • /
    • 2005
  • This study was carried out to investigate the antioxidant effects of melanin extracts, including silkie fowl skin melanin (SS-melanin), silkie fowl comb melanin (SC-melanin), sepia ink sac melanin (SE-melanin), octopus ink sac melanin (OC-melanin) and synthetic melanin (SY-melanin). The results showed that with the addition of melanin extracts, linoleic acid peroxide significantly, decreased (p<0.05) with the increase in the irradiative time of UV and that OC-melanin had the highest efficiency on antioxidant activity (p<0.05). Melanin extract had reducing power and chelating power to $Fe^{2+}$, which increased with the increase in the different melanin concentration. Therefore, it could be concluded that the antioxidant action of melanin extracts did not come from one single function, but is a result of many characteristic functions.

Changes of Blood Flow Characteristics for different Coil Locations after the Embolisation of Lateral Aneurysms (측방 동맥류 색전술 후 코일 위치에 따른 혈류 유동의 변화)

  • 이계한;송계웅;변홍식
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2002.05a
    • /
    • pp.124-127
    • /
    • 2002
  • Ceil embolisation technique has been used to treat the intracranial aneurysms. Microcoils inserted into the aneurysm sac induce the blood flow stagnation inside the aneurysm sac, which causes the thrombus formation and embolisation of aneurysm. Since the intraaneurysmal flow patterns affect the embolisation process, we want to measure the flow field for different locations of coil inside the aneurysm sac . Lateral aneurysm models are manufactured using rapid prototyping, and the velocity fields are measured using particle image velocitimeter. Distally blocked models showed less flow into the aneurysm sac comparing to proximally blocked models. Also blocking the neck of aneurysm showed better inflow blocking comparing to blocking the dome of aneurysm. These results suggest that distal neck should be the preferred locations of coil for aneurysm embolisation.

  • PDF

Endolymphatic Sac Tumors : Report of Four Cases

  • Bae, Chae-Wan;Cho, Young-Hyun;Chung, Jong-Woo;Kim, Chang-Jin
    • Journal of Korean Neurosurgical Society
    • /
    • v.44 no.4
    • /
    • pp.268-272
    • /
    • 2008
  • Endolymphatic sac tumor is rare, locally aggressive hypervascular tumor of papillary structure, arising from the endolymphatic duct or sac in the posterior petrous bone. We present four cases with this tumor. Two patients were male and the other two were female. Age of each patient was 15, 52, 58, and 67 years. Three patients presented with progressive hearing loss and sustained vertigo for months to years and another one was referred for the tumor detected in routine medical check-up. Preoperative embolization was performed in 3 patients. Complete excision of the tumor was achieved in all patients using translabyrinthine or retrosigmoid approach. Herein, we describe the clinical and radiographic features, surgical treatment and pathologic findings with a review of the literature.

Slewing maneuver control of flexible space structure using adaptive CGT

  • Shimada, Yuzo
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1995.10a
    • /
    • pp.47-50
    • /
    • 1995
  • This paper concerns an adaptive control scheme which is an extension of the simplified adaptive control. Originally, the SAC approach was developed based on the command generator tracker (CGT) theory for perfect model tracking. An attractive point of the SAC is that a control input can be synthesized without any prior knowledge about plant structure. However, a feedforward dynamic compensator of the CGT is removed from the basic structure of the SAC. This deletion of the compensator makes perfect model tracking difficult against even a step input. In this paper, an adaptive control system is redesigned to achieve perfect model tracking for as long as possible by reviving the dynamic compensator of the CGT. The proposed method is applied to slewing control of a flexible space structure and compared to the SAC responses.

  • PDF

Numerical Study of 3D Unsteady Flow in a Blood Sac of TPLS: Effect of Actuator Speed (TPLS 혈액주머니 내의 3차원 비정상유동에 대한 수치해석 연구: 액추에이터 속도의 영향)

  • Jung G. S.;Seong H. C.;Park M. S.;Ko H. J.;Shim E. B.;Min B. G.;Park C. Y.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2003.08a
    • /
    • pp.206-211
    • /
    • 2003
  • This paper reports the numerical results for blood flow of the sac squeezed by moving actuator in the TPLS(Twin Pulse Life Support System). Blood flow in the sac is assumed to be 3-dimensional unsteady newtonian fluid. where the blood flow interacts with the sac, which is activated by the moving actuator. The flow field is simulated numerically by using the FEM code, ADINA. It is well known that hemolysis is closely related to shear stress acted on blood flow. According to this fact, we simulate four models with different speed for moving actuator and examine the distribution of shear stress for each model. Numerical results show that maximum shear stress is strongly dependent on the actuator speed.

  • PDF

Hull Form Generation by Using Fuzzy Model

  • Lee, Yeon-Seung-;Jeong, Seong-Jae;Kim, Su-Young-;Geuntaek-Kang
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 1993.06a
    • /
    • pp.1234-1237
    • /
    • 1993
  • This paper discusses the hull form generation from fuzzy model constructed with actual ship data using fuzzy concept. SAC, which is the most important factor in the hull form generation, is expressed by a fuzzy model describing the relationships among design parameters, which have a great influence on SAC, through model identification process with the actual ship data and design parameters. Then, we can infer the SAC of an aimed ship through the process of fuzzy inference and decide the offset of a front view by making the fuzzy model between SAC and offset as well. In conclusion, this paper makes a step forward from the geometrical definition, which has been used for hull form generation so far, to direct mathematical formulae about the relationship between design parameters and offset. So, if the design parameters are given, we can generate the hull form taking such properties into account.

  • PDF

On the Cryptogeaphic Signigicance of Bent Functions (Bent 함수의 암호학적 성질에 관한 고찰)

  • 김광조
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.1 no.1
    • /
    • pp.85-90
    • /
    • 1991
  • After we introduce the properties of bent functions satisfying the SAC(Strict Avalanche Criterion), we made cldar the relationship between two functions, i.e., all Boolean functions satisfying the maximum order SAC. Bant function will be useful to implement cryptographic functions like S-boxes of block cipher, nonlinear combiners, etc. But due to thear 0/1 unbalance and their existence for only even number of input bits, bent functions have some restrictions to use as a building block for constructing bijective cryptographic functions.

On the Reward Function of Latent SAC Reinforcement Learning to Improve Longitudinal Driving Performance (종방향 주행성능향상을 위한 Latent SAC 강화학습 보상함수 설계)

  • Jo, Sung-Bean;Jeong, Han-You
    • Journal of IKEEE
    • /
    • v.25 no.4
    • /
    • pp.728-734
    • /
    • 2021
  • In recent years, there has been a strong interest in the end-to-end autonomous driving based on deep reinforcement learning. In this paper, we present a reward function of latent SAC deep reinforcement learning to improve the longitudinal driving performance of an agent vehicle. While the existing reward function significantly degrades the driving safety and efficiency, the proposed reward function is shown to maintain an appropriate headway distance while avoiding the front vehicle collision.

Enhancing Video Storyboarding with Artificial Intelligence: An Integrated Approach Using ChatGPT and Midjourney within AiSAC

  • Sukchang Lee
    • International Journal of Advanced Culture Technology
    • /
    • v.11 no.3
    • /
    • pp.253-259
    • /
    • 2023
  • The increasing incorporation of AI in video storyboard creation has been observed recently. Traditionally, the production of storyboards requires significant time, cost, and specialized expertise. However, the integration of AI can amplify the efficiency of storyboard creation and enhance storytelling. In Korea, AiSAC stands at the forefront of AI-driven storyboard platforms, boasting the capability to generate realistic images built on open datasets foundations. Yet, a notable limitation is the difficulty in intricately conveying a director's vision within the storyboard. To address this challenge, we proposed the application of image generation features from ChatGPT and Midjourney to AiSAC. Through this research, we aimed to enhance the efficiency of storyboard production and refined the intricacy of expression, thereby facilitating advancements in the video production process.

Infiltrative Lipoma Invading the Anal Sac in a Dog: A Rare Case Report

  • Junyoung Kim;Dai Jung Chung;Jihye Choi;Junghee Yoon
    • Journal of Veterinary Clinics
    • /
    • v.40 no.2
    • /
    • pp.147-151
    • /
    • 2023
  • A 6-year-old female Chihuahua was presented to the Animal Medical Center for surgical resection of a perineal mass that had recently increased in size. Ultrasonography revealed a large, homogeneous fatty mass with irregular margins between the surrounding muscle layers due to infiltrating fatty tissues. Cytological findings from fine-needle aspirates revealed numerous sheets and clusters of adipocytes, which was consistent with the fatty mass. Based on ultrasonographic and cytological findings, an infiltrative lipoma was suspected. During the surgery, the perineal mass was found to be non-encapsulated, irregularly marginated, and extensively distributed into the surrounding muscles. The mass extended inside the pelvic cavity and left anal sac. The perineal mass was surgically removed and submitted for histopathologic examination. Histopathology confirmed that the mass was an infiltrative lipoma invading into the anal sac and surrounding muscles. The present report was an unusual presentation of infiltrative lipoma that invaded the anal sac in the perineum.