• Title/Summary/Keyword: defense performance

Search Result 2,006, Processing Time 0.04 seconds

Development of the Power Assist System for High Efficiency and Lightweight Wearable Robot in Unstructured Battlefield (비정형화된 전장 환경에 활용 가능한 고효율-경량형 외골격 착용 로봇의 근력 보조 시스템 개발)

  • Huichang Park
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.26 no.4
    • /
    • pp.313-323
    • /
    • 2023
  • The wearable robot system is designed to assist human skeletal and muscular systems for enhancing user's abilities in various fields, including medical, industrial, and military. The military has an expanding need for wearable robots with the integration of surveillance/control systems and advanced equipment in unstructured battlefield environments. However, there is a lack of research on the design and mechanism of wearable robots, especially for power assist systems. This study proposes a lightweight wearable robot system that provides comfortable wear and muscle support effects in various movements for soldiers performing high-strength and endurance missions. The Power assist mechanism is described and verified, and the tasks that require power assist are analyzed. This study explain the system including its driving mechanism, control system, and mechanical design. Finally, the performance of the robot is verified through experiments and evaluations, demonstrating its effectiveness in muscle support.

A Study on the Proper Inspection Cycle Plan Through Reliability Analysis of One-Shot System (One-Shot System의 신뢰도 분석을 통한 적정 점검주기 방안 연구)

  • June-Young Lim;Hyeonju Seol
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.46 no.1
    • /
    • pp.48-54
    • /
    • 2023
  • Guided missiles are a one-shot system that finishes their purpose after being used once, and due to the long-term storage until launch, the storage reliability is calculated during development, and performance is maintained through periodic inspections until the life cycle arrives. However, the reliability standards applied in the development of guided missiles were established by analyzing data accumulated by the United States during long-term operation in the country, and since they are different from our environment, the 00 guided missiles that have been deployed in the armed forces for more than 10 years under the premise that there is a difference from actual reliability. As a result of verifying the appropriateness of the current inspection cycle by analyzing the actual reliability of the missile, the necessity of changing the inspection period was derived because it was higher than the predicted reliability. It is proposed to build and utilize a lifespan management system that can systematically collect all data such as shooting and maintenance results by classification, and to establish a reliable reliability standard based on the accumulated data.

Acid sphingomyelinase inhibition alleviates muscle damage in gastrocnemius after acute strenuous exercise

  • Lee, Young-Ik;Leem, Yea-Hyun
    • Korean Journal of Exercise Nutrition
    • /
    • v.23 no.2
    • /
    • pp.1-6
    • /
    • 2019
  • [Purpose] Strenuous exercise often induces skeletal muscle damage, which results in impaired performance. Sphingolipid metabolism contributes to various cellular processes, including apoptosis, stress response, and inflammation. However, the relationship between exercise-induced muscle damage and ceramide (a key component of sphingolipid metabolism), is rarely studied. The present study aimed to explore the regulatory role of sphingolipid metabolism in exercise-induced muscle damage. [Methods] Mice were subjected to strenuous exercise by treadmill running with gradual increase in intensity. The blood and gastrocnemius muscles (white and red portion) were collected immediately after and 24 h post exercise. For 3 days, imipramine was intraperitoneally injected 1 h prior to treadmill running. [Results] Interleukin 6 (IL-6) and serum creatine kinase (CK) levels were enhanced immediately after and 24 h post exercise (relative to those of resting), respectively. Acidic sphingomyelinase (A-SMase) protein expression in gastrocnemius muscles was significantly augmented by exercise, unlike, serine palmitoyltransferase-1 (SPT-1) and neutral sphingomyelinase (N-SMase) expressions. Furthermore, imipramine (a selective A-SMase inhibitor) treatment reduced the exercise-induced CK and IL-6 elevations, along with a decrease in cleaved caspase-3 (Cas-3) of gastrocnemius muscles. [Conclusion] We found the crucial role of A-SMase in exercise-induced muscle damage.

Athermal Design and Performance Verification of an LWIR Zoom Lens for Drones

  • Kwang-Woo Park;Sung-Chan Park
    • Current Optics and Photonics
    • /
    • v.8 no.4
    • /
    • pp.366-374
    • /
    • 2024
  • This paper presents an optimum method for determining the parameters to athermalize a long-wavelength infrared (LWIR) zoom camera by introducing the defocus sensitivity analysis. To effectively find parameters that significantly affect thermal defocus, we simulated athermal analysis with temperature changes for all variables. Consequently, we found that the optimum parameter to correct thermal defocus is the compensation lens, and its movements with temperature at each zoom position are obtained from the simulated athermal analysis. To verify the efficiency of our athermal approach, we performed actual athermal tests in a broad temperature range at each zoom position. The simulated athermal analysis provides the initial position of the compensation lens at the corresponding temperature and zoom position. Then the compensation lens is elaboratively moved to serve the highest live contrast ratio (LCR) for the target. This experiment shows that the compensation lens locations in the actual test are closely matched to those in the simulated athermal analysis. In addition, two outdoor tests conducted in two different environments confirm that the autofocus system suggested in this study performs well at all zoom positions. Using the proposed athermal analysis approach in this paper, we efficiently realize an athermal system over the specified temperature and zoom ranges.

Design of an Initial-position Update Mooring Alignment Algorithm for Dual-axis Rotational INS Using a Kalman Filter (칼만 필터를 이용한 2축 회전형 관성항법장치의 초기위치 보정 정박 중 정렬 알고리즘 설계)

  • Kyung-don Ryu
    • Journal of Advanced Navigation Technology
    • /
    • v.28 no.4
    • /
    • pp.379-385
    • /
    • 2024
  • INS(inertial navigation system) aligns itself using gravity and Earth's rotational rate from accelerometers and gyro sensors when stationary. Typically, ZUPT(zero velocity update), which is based on a linear error model Kalman filter, is used when it is stationary. However, such algorithms assume stationary conditions, leading to increased alignment errors or filter divergence during maritime mooring due to wave-induced motion. This paper designs a mooring alignment algorithm for maritime platforms using a Kalman filter, which uses large heading angle error model and an initial position correction technique. And it is validated by simulation. Furthermore, it is confirmed that applying this to a rotational INS dramatically improves performance through the principle of bias cancellation.

Multimode-fiber Speckle Image Reconstruction Based on Multiscale Convolution and a Multidimensional Attention Mechanism

  • Kai Liu;Leihong Zhang;Runchu Xu;Dawei Zhang;Haima Yang;Quan Sun
    • Current Optics and Photonics
    • /
    • v.8 no.5
    • /
    • pp.463-471
    • /
    • 2024
  • Multimode fibers (MMFs) possess high information throughput and small core diameter, making them highly promising for applications such as endoscopy and communication. However, modal dispersion hinders the direct use of MMFs for image transmission. By training neural networks on time-series waveforms collected from MMFs it is possible to reconstruct images, transforming blurred speckle patterns into recognizable images. This paper proposes a fully convolutional neural-network model, MSMDFNet, for image restoration in MMFs. The network employs an encoder-decoder architecture, integrating multiscale convolutional modules in the decoding layers to enhance the receptive field for feature extraction. Additionally, attention mechanisms are incorporated from both spatial and channel dimensions, to improve the network's feature-perception capabilities. The algorithm demonstrates excellent performance on MNIST and Fashion-MNIST datasets collected through MMFs, showing significant improvements in various metrics such as SSIM.

Design of Framework for Quality Level Diagnosis of Military Supplies (군수품 품질수준진단 프레임워크 설계)

  • Yo Han Kang;Jin Young Choi
    • Journal of Korean Society for Quality Management
    • /
    • v.52 no.3
    • /
    • pp.495-508
    • /
    • 2024
  • Purpose: The purpose of this study was to propose a framework for quality level diagnosis of military supplies, which consists of 7 steps for developing questionnaires and suggesting improvement guidelines. Methods: We analyze the required functions of the equipment under investigation, classify the main components, review quality characteristics, develop a quality level checklist through the first and second stages of quality function deployment, and evaluate and analyze the results of the quality level survey applied to this checklist. Results: We first compared and analyzed case studies of domestic and international military and civilian quality level surveys and proposed a framework for diagnosing the quality levels of military supplies. Additionally, we applied the proposed quality level diagnosis framework to a specific weapon system to analyze its quality characteristics and identify improvement directions, thereby verifying the applicability of the proposed frame- work for diagnosing the quality levels of military supplies. Conclusion: The results of this study, which include the application of the proposed diagnostic framework for quality investigation and analysis, can be used to understand the satisfaction with the military supplies currently in operation. This will enable the continuous assurance of quality related to the functions and performance required by the military weapon systems.

Robust Skyline Extraction Algorithm For Mountainous Images (산악 영상에서의 지평선 검출 알고리즘)

  • Yang, Sung-Woo
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.47 no.4
    • /
    • pp.35-40
    • /
    • 2010
  • Skyline extraction in mountainous images which has been used for navigation of vehicles or micro unmanned air vehicles is very hard to implement because of the complexity of skyline shapes, occlusions by environments, dfficulties to detect precise edges and noises in an image. In spite of these difficulties, skyline extraction is avery important theme that can be applied to the various fields of unmanned vehicles applications. In this paper, we developed a robust skyline extraction algorithm using two-scale canny edge images, topological information and location of the skyline in an image. Two-scale canny edge images are composed of High Scale Canny edge image that satisfies good localization criterion and Low Scale Canny edge image that satisfies good detection criterion. By applying each image to the proper steps of the algorithm, we could obtain good performance to extract skyline in images under complex environments. The performance of the proposed algorithm is proved by experimental results using various images and compared with an existing method.

Measurement and Validation of Infrared Signature from Exhaust Plume of a Micro-Turbo Engine (마이크로 터보 엔진 배기 플룸에서의 적외선 신호 측정 및 검증)

  • Gu, Bonchan;Baek, Seung Wook;Jegal, Hyunwook;Choi, Seongman;Kim, Won Cheol
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.44 no.12
    • /
    • pp.1054-1061
    • /
    • 2016
  • Development of an accurate infrared signature (IR) measurement system is expected to contribute in the development of low observable technology and the spectroscopic analysis of electromagnetic radiation. Application of a spectroradiometer (SR) allows for the measurement of detailed infrared signature from the exhaust plume due to its own heat source. Establishment of a measurement system using a micro-turbo engine is intended to simulate the modelling of the aircraft plume. The engine was installed on a test stand to measure the engine performance. The IR signature was measured by placing the SR perpendicular to the axis line of the exhaust plume. Reference data from the blackbody were also measured to calibrate the raw data, and the infrared signature of the background was also measured for comparison with that of the plume. The calibrated spectral radiance was obtained through the data reduction process and the results were analyzed in specific bands. The experiments revealed that the measurement system established here showed sufficient performance for further comprehensive analysis.

Study on Resistance Performance of Icebreaking Cargo Vessel in Pack Ice Condition according to Variation of Synthetic Ice Thickness and Hull Form Characteristics (합성얼음의 두께변화와 선형변화에 따른 Pack ice 상태에서의 쇄빙상선의 저항특성 연구)

  • Lee, Seung-Ho;Kim, Moon-Chan;Chun, Ho-Hwan;Cho, Jun-Cheol;Shin, Byung-Chul;Jung, Un-Hwa
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.46 no.5
    • /
    • pp.471-478
    • /
    • 2009
  • The present paper deals with characteristics of resistance performance according to the variation of synthetic ice thickness and hull form. The resistance test has been conducted with pack ice condition in Pusan National University towing tank. Stem angle has been chosen as main parameters for the variation of hull form characteristics, which is the most important factor especially in icebreaking cargo vessel. The serial comparisons of resistance test have been done with the variation of hull form parameter as well as with the different thickness of synthetic ice. The different trend of resistance performances with increasing of stem angle has been shown at each synthetic ice thickness. The present test results is expected to be confirmed by comparing the test results in ice tank in the near future.