• Title/Summary/Keyword: Acquisition Environment

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The Acquisition of the PN Code in the DS/CDMA System Considering Phase Error and Rake Receiver (위상 오류와 레이크 수신기를 고려한 DS/CDMA 시스템의 PN 부호 획득)

  • 김원섭;장문기;박진수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.4
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    • pp.527-534
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    • 2002
  • In this paper, efficiency in the acquisition of the PN code of the DS/CDMA system was analyzed by using the Nakagami-m probability density function that can model diverse fading channels. The system considers the fading environment that inevitably exists in the mobile communications channel environment. To analyze the efficiency of the system, the equations related to detection probability PD and false alarm probability PFA required for the acquisition of the PN code were induced by using the Nakagami-m probability density function. They were verified through simulation. For the DS/CDMA system an adaptive serial search technique was applied to acquire the PN code. To correct phase error, the equations related to detection probability PD and false alarm probability PFA that influence the time to acquire codes were induced after adding the PLL to each branch of the Rake Receiver. By using an induced equation, detection probability PD and false alarm probability PFA were verified through simulation.

A Development of OMS/MP Templete of Guided Weapons on Board Ship (함정탑재 유도무기에 대한 OMS/MP 템플릿 개발)

  • Kwon, Yong-Soo;Lee, Kyoung-Haing
    • Journal of the military operations research society of Korea
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    • v.33 no.2
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    • pp.17-29
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    • 2007
  • This work describes a basic process of OMS/MP in guided weapons on board ship. The OMS/MP which provided basic data of ROC & RAM analysis must be prepared by user But data acquisition Quantified by specific operational environment of ship and related preparing instructions which are not established are now insufficient of reliable weapon systems acquisition. The OMS/MP is an important area that become measures of Acceptance Test and doctrine considering future battlespace environment From a development of the OMS/MP template that describe systematically and as quantitative of shipped guided weapons, combat developer oriented product development & reliable weapon system acquisition are ta be accomplished. This research developed OMS/MP preparation templete that presented quantified OMS/MP derivation and RAM target value calculation process which provide optimum weapon systems design concept to research developers

A GPS Initial Synchronization Method for Robust DGPS Reference Stations in Noisy Environment (잡음환경에 강인한 DGPS 기준국을 위한 GPS 초기동기 방법)

  • Park Jeong-Yeol;Park Sang-Hyun;Sin Jae-Ho
    • Journal of Navigation and Port Research
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    • v.30 no.5 s.111
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    • pp.343-349
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    • 2006
  • In order to enhance the robustness against noisy environment, the previous GPS initial synchronization method of DGPS reference stations adopts not only the coherent integration method but also the non-coherent integration method. However the previous GPS initial synchronization method muses the non-coherent integration loss, which is a dominant factor among the signal acquisition losses in noisy environment. And the non-coherent integration loss increases with the strength of noise signal. In this paper, a novel GPS initial synchronization method is proposed for robust DGPS reference stations in noisy environment. This paper presents that the proposed GPS initial synchronization method suppresses the non-coherent acquisition loss. Furthermore, with regard to the mean acquisition time, it is shown that the number of the search cells of the proposed GPS initial synchronization method is much smaller than that of the previous GPS initial synchronization method Finally, through the simulation by the GPS simulator, it is seen that the GPS signal of nigh signal-to-noise ratio can be acquired under increased noise floor using the proposed GPS initial synchronization method.

The Design of a Small GNSS Receiver with Enhanced Interference Suppression Capability for High Mobility

  • Park, Yong-Hyun;Moon, Sung-Wook;Shin, Bong-Gyu;Oh, Jong-Su
    • Journal of Positioning, Navigation, and Timing
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    • v.4 no.1
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    • pp.9-16
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    • 2015
  • The applications of Global Navigation Satellite System (GNSS) receivers are becoming wider in various commercial and military systems including even small weapon systems such as artillery shells. The precision-guided munitions such as Small Diameter Bomb (SDB) of United States can be used for pinpoint strike by acquiring and tracking GNSS signals in high mobility situation. In this paper, a small GNSS receiver with embedded interference suppression capability working under high dynamic stress is developed which is applicable to the various weapon systems and can be used in other several harsh environments. It applies a kind of matched filter and multiple correlator schemes for fast signal acquisition and tracking of even weak signals and frequency domain signal processing method to eliminate the narrowband interference. To evaluate the performance of the developed GNSS receiver, the test scenario of high mobility and interference environment with the GNSS simulator and signal generator is devised. Then, the signal acquisition time, navigation accuracy, sensitivity, and interference suppression performances under high dynamic operation are evaluated. And the comparison test with the commercial GNSS receiver which has high sensitivity is made under the same test condition.

Does Environmental Responsibility Lower 'Double Hurdle'? Emerging Multinationals in Global Natural-Resource Industry

  • Qingwei NAN;Bo Kyung KIM;Jooyoung KWAK
    • Asian Journal of Business Environment
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    • v.13 no.4
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    • pp.19-28
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    • 2023
  • Purpose: Emerging markets under industrialization have become increasingly influential over the global natural-resource transactions. However, their average deal completion rates have been relatively low. The international business (IB) literature regards the low rate as evidence of 'double hurdle', the extra disadvantages in doing overseas business for firms from developing countries. Because legitimacy building mitigates liability of foreignness, we argue that an acquirer's environmental responsibility effectively builds legitimacy. Research design, data and methodology: Stakeholders in the host country spread the acquirer's environmental responsibility so that, by raising legitimacy, they may strengthen the link between environmental responsibility and deal completion. Our dataset consists of the 608 cross-border acquisition deals announced by the 196 firms in Brazil, Russia, India, and China over 2008-2019 period. Results: A logit regression result confirms that environmental responsibility increases the likelihood of acquisition deal completion. Also, host-market stakeholders positively moderate the relationship between environmental responsibility and the likelihood of deal completion. Conclusions: Overall, this study contributes to the IB literature by identifying environmental responsibility as a key approach to lowering the double hurdle in internationalization of firms in emerging markets. Any emerging multinationals interested in the foreign, brownfield entries to the natural-resource industries must enhance the environmental responsibility, which turns out extremely important.

A Study on the Design Methodology of SE-Based Military Force Construction in Defense Acquisition Process (Focusing on Influencing Factor Priorities) (국방획득 과정에서 SE개념 기반의 군사력건설 설계 방법론 연구(영향요인 우선순위 결정 중심으로))

  • Kim, Heung Bin;Seo, Je Hyeon
    • Journal of the Korean Society of Systems Engineering
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    • v.15 no.2
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    • pp.87-97
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    • 2019
  • This paper focuses on the SE concept based on the weapon system design, which is the lack of systematic research at the stage of military requirements creation prior to acquisition management phase. Influence factors were derived by focusing on the core issues that were at issue in the process of requirements analysis, requirements verification, and business management in recent years. Next, the impact factor was prioritized using the AHP technique and then alternatives were suggested. As a result, through the hierarchical analysis process, 'substantiation of necessity' was found to be the most important factor in the large category, and 'satisfaction of the operating concept' was the most important factor. In addition, as a result of calculating the final weight for each nutritional factor, it was analyzed in order of 'enemy threat response ability', 'response to operational environment change', 'performance considering operational environment', and 'guaranteed power generation'. The results of this analysis suggest which factors should be focused on, firstly, based on the concept of SE by the military and JCS.

A Study on the Operational Plan and Acquisition Method for CO2 Carrier by Retrofitting Existing Vessels and New Ship-Building (중고선 개조와 신조에 의한 CO2 운송선 확보 및 운용방안에 관한 연구)

  • Shin, Myung-Soo;Park, Beom Jin;Ki, Min Suk;Lee, Dae Hak
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.1
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    • pp.15-21
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    • 2015
  • This paper presents the feasibility study on $CO_2$ carrier for carbon dioxide marine geological storage. Conceptual design was carried out to acquire $CO_2$ carriers by retrofitting existing vessels and new ship-building. Based on conceptual design, the acquisition cost of $CO_2$ carriers was estimated. Finally, necessary expense and number of ships were estimated based on operational plans for the assumed scenario.

The Design and Implementation of TDD-OFDMA Feedback Signal Cancellation(FSC) Digital RF Repeater (TDD-OFDMA 방식의 귀환 신호 제거 디지털 RF 중계기 설계 및 구현)

  • Ryoo Gyoo-Tae;Kim Dae-Yen;Park Se-Jun
    • 한국정보통신설비학회:학술대회논문집
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    • 2006.08a
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    • pp.57-61
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    • 2006
  • As high speed internet users are tremendously increasing, three are keenly in need of development of high speed portable internet technology which can provide high quality wireless internet service cheaply even in the mobile. Unlike the FDD-CDMA, TDD-OFDMA has relatively poor wave environment with inducing interference, fading and delay because it agrees to multi-carrier modulation method and time-division radio telecommunication system. To solve this problem, it is necessary to develop repeater operating by digital signal processing method which have more strict wireless channel control and wave signal processing technology over TDD telecommunication equipments. This thesis is dealing with design and implementation of Digital RF Repeater which implemented 'Synchronization Acquisition Unit', 'TDD signal switching Unit', 'Feedback Signal Cancellation Unit'. Over this argument, we will develop digital RF repeater with more cheap, more adaptive in wave environment like oscillation control, adaptive wave monitoring and output increasing and having control function as a result it will be helpful for success in high speed portable internet service business.

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Forest Environment Monitoring Application of Intelligence Embedded based on Wireless Sensor Networks

  • Seo, Jung Hee;Park, Hung Bog
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.4
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    • pp.1555-1570
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    • 2016
  • For monitoring forest fires, a real-time system to prevent fires in wider areas should be supported consistently. However, there has still been a lack of the support for real-time system related to forest fire monitoring. In addition, the 'real-time' processing in a forest fire detection system can lead to excessive consumption of energy. To solve these problems, the intelligent data acquisition of sensing nodes is required, and the maximum energy savings as well as rapid and accurate detection by flame sensors need to be done. In this regard, this paper proposes a node built-in filter algorithm for intelligent data collection of sensing nodes for the rapid detection of forest fires with focus on reducing the power consumption of the remote sensing nodes and providing efficient wireless sensor network-based forest environment monitoring in terms of data transmission, network stability and data acquisition. The experimental result showed that battery life can be extended through the intelligent sampling of remote sensing nodes, and the average accuracy of the measurement of flame detection based on the distance is 44%.

A Study on Use of Environment-Friendly Agricultural Products and Agricultural Safety Consciousness of Consumers (소비자의 환경친화적 농산물 이용과 안전 의식에 관한 연구)

  • Ko, Jung-Sook;Lee, Chae-Shik
    • Hwankyungkyoyuk
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    • v.20 no.4
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    • pp.117-131
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    • 2007
  • The objectives of this study were to investigate using environment-friendly agricultural products and to analyze consciousness of agricultural safety of consumers. The data were collected from 1,000 consumers by two-staged stratified random sampling. SPSSWIN/ver. 13 program was used for analyzing data with frequency, cross-tab, t-test and ANOVA. The major findings of this study were as follows: 1) Consumers with higher academic career, more income, and white collars showed higher experiences on environment-friendly agricultural products. 2) Consumers who are under thirties, university graduation and upper income revealed high intention to use environment-friendly agricultural products. 3) The study revealed information needs and information acquisition are significantly different among consumers 4) Consumers with higher academic and upper income showed higher agricultural safety concern, 5) The study discovered that consumers who are over sixties and under middle school graduation were higher on agricultural safety effects.

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