• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.133-136
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• 2000

Generally in the case of mobil communication service for long distance sea, unlike heavily populated residential areas, providers need to minimize the service area per base station. Therefore, in this thesis, the 800 ㎒ CDMA system should be extended to give better long distance communication service. This model is used to predict the occurring receiving power of the mobile stations that we simulated and analyzed. As a result, the experiment demonstrated the appropriateness of predicting receiving power using this model.

• Journal of Biomedical Engineering Research
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• v.13 no.3
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• pp.201-208
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• 1992

In the indirect optical bio-telemetry, high frequency response and low minimum detectable optical power can be achieved by using photodiode with small light receiving area which minimizes junction capacitance. But, on the other hand, S/N ratio becomes low because the optical signal current is small. To solve such a problem, we attach plato-convex lens in front of photo diode, The results of comput- er simulation and experiments suggest promotion of light receiving efficiency and possibility of multi- telemetry system through directivity of convex lens in one room.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.7
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• pp.1520-1525
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• 2009

In this paper, we study and simulate the suggested position control system using GPS and USN to replace the existing control system of a crane. For the correct approach, the position control system of a crane is divided into the control system of the ground station and the mobile station The hardware is comprised of GPS receiving module to receive the position control data of a crane from GPS satellites, bluetooth communication module for the data communication between the ground station and the mobile station, supersonic sensor module for a precise position control of a crane, motor to replace a crane roller, embedded MCU(ATmega128L) and so on. In here, an embedded MCU controls GPS receiving module, bluetooth communication module and supersonic sensor module. The Software is comprised of three programs. Three programs are the program to filter GGA output part in a receiving data of GPS receiving module, the driving program for supersonic sensor module, the digital map program to monitor a crane location. From the simulation results, it is demonstrated that the proposed system has the capability of crane position control with 1cm precision.

• The Korean Journal of Community Living Science
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• v.18 no.2
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• pp.313-321
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• 2007

The study examined the level of understanding and satisfaction of parents who should receive the food materials and monitor the food service, and would provided the basic data for more desirable school feeding system. The analysis was based on the participation level in materials receiving and food service monitoring, condition of equipment, knowledge about materials and the opinions about monitoring education. 160 monitors out of Daejeon primary schools were used and 60% of them were in the age of thirties and the others were in forties. Equipment condition for material receiving was good and most of the monitors were familiar with the ways of using the machines. Difficulties of material receiving were found in meat(65.6%) and sea food(21.9%), and the ratios of activities and the intention to participate in monitoring education were high with 25.0% and 72.5% respectively. Most of the monitors thought sanitary conditions of food materials(100.0%) and delivery persons(96.9%) were very good or good. And 90% of the respondents changed their perception of school food service positive after monitoring. In conclusion, most of the parents wanted to participate in the monitoring and material receiving actively and showed great willingness to receive monitoring education.

• Journal of the Korea Safety Management & Science
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• v.4 no.3
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• pp.79-93
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• 2002

Cross docking is a material handling and distribution concept in which products move directly from receiving dock to shipping dock, without being stored in a warehouse or distribution center. Depending on the facility and operating conditions or strategies employed, it is possible to generate various cross docking scenarios or models. The cross docking model, which is studied in this research, assumes there are a separate receiving dock and a separate shipping dock. It is also assumed that the products contained in a receiving truck and the products needed for a shipping truck are known in advance. Furthermore, the study is restricted to scenarios where there is only one receiving dock and only one shipping dock at the warehouse. The research objective is to find the best truck spotting sequence for both receiving and shipping trucks to minimize total operation time (i.e., the makespan) of the cross docking system.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.3
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• pp.352-359
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• 2018

As a fuel for ship propulsion, liquefied natural gas (LNG) is currently considered a proven and reasonable solution for meeting the IMO emission regulations, with gas engines for the LNG-fueled ship covering a broad range of power outputs. For an LNG-fueled ship, the LNG bunkering process is different from the HFO bunkering process, in the sense that the cryogenic liquid transfer generates a considerable amount of boil-off gas (BOG). This study investigated the effect of the temperature difference on boil-off gas (BOG) production during ship-to-ship (STS) LNG bunkering to the receiving tank of the LNG-fueled ship. A concept design was resumed for the cargo/fuel tanks in the LNG bunkering vessel and the receiving vessel, as well as for LNG handling systems. Subsequently, the storage tank capacities of the LNG were $4,500m^3$ for the bunkering vessel and $700m^3$ for the receiving vessel. Process dynamic simulations by Aspen HYSYS were performed under several bunkering scenarios, which demonstrated that the boil-off gas and resulting pressure buildup in the receiving vessel were mainly determined by the temperature difference between bunkering and the receiving tank, pressure of the receiving tank, and amount of remaining LNG.

• Journal of Positioning, Navigation, and Timing
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• v.2 no.1
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• pp.1-8
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• 2013

A signal system for improving the code acquisition complexity of Global Navigation Satellite System (GNSS) receiver is proposed and the receiving correlator scheme is presented accordingly. The proposed signal system is a hierarchical code type with a duplexing configuration which consists of the Zadoff-Chu (ZC) code having a good auto-correlation characteristic and the Pseudo Random Noise (PRN) code for distinguishing satellites. The receiving correlator has the scheme that consists of the primary correlator for the ZC code and the secondary correlator which uses the PRN code for the primary correlation results. The simulation results of code acquisition using the receiving correlator of the proposed signal system show that the proposed signal scheme improves the complexity of GNSS receiver and has the code acquisition performance comparable to the existing GNSS signal system using Coarse/Acquisition (C/A) code.

• Journal of Aerospace System Engineering
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• v.15 no.5
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• pp.113-128
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• 2021

In this paper, we present a simple ground receiving station as an educational method for a satellite system. Our system is produced similarly to the existing fixed ground station in terms of function by using satellite communication technology and related software commonly used in the amateur radio field. In addition, we conducted operation test to receive signals from operating satellites and confirmed the possibility of using them as a way to educate satellite systems, such as understanding ground station systems through satellite reception experience and satellite state information acquisition, and further designing satellite systems.

• Journal of Korea Society of Industrial Information Systems
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• v.15 no.2
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• pp.17-22
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• 2010

Establishment of systematic platform is needed for technological progress of receiving of satellite image data with high quality and processing system for product generation and operation related with direct receiving system for satellite from abroad. Besides, it's necessary to develop the integrated data processing system to prohibit similar functions on developing (or being developed) for KOMPSAT-3, KOMPSAT-5 and to operate system efficiently. Therefore, conceptual design of the integrated data processing system is performed considering commercialization of KOMPSAT(Korea Multi-Purpose Satellite) series based on KOMPSAT-2 IRPE on operation in this paper.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.810-814
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• 2002

According to the image level definition for KOMPSAT-2 in KOMPSAT-2 Ground Station Specification, the level 0 is frame formatted, unprocessed data at full resolution; any and all communications artifacts (e.g., synchronization frames, communications headers) removed. The level 0 is used for two purposes: 1) exchange of imagery between image receiving & processing element (IRPE), and 2) image transfer from the Receiving & Archiving Subsystem to Search & Processing Subsystem. On-board processing of imagery data of KOMPSAT-2 includes JPEG-like compression and encryption besides conventional CCSDS packetization. The encryption is used to secure imagery data from any intervention during downlink and compression allows real-time downlink of image data reducing data rate produced from the camera. While developing ground receiving system for KOMPSAT-2, it was necessarily to define level 0 products. In this paper, we will suggest level 0 product definition for KOMPSAT-2 and explain reasons of the decisions made. The key factor used while defining the level 0 products is the efficiency of whole ground receiving system. The latter half of the paper will explain the implementation of software that generates level 0 products. The necessary steps to produce level 0 products will be explained, and the performance achieved will be presented.