• Title/Summary/Keyword: Uncertainty processing

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A Study on the Management of the Indian Ocean Tuna Fishing Grounds (인도양 다랭이어업의 어장관리에 관한 연구)

  • Gong, Yeong;Park, Yeong-Chull;Yang, Won-Seok;Lee, Je-Hu
    • The Journal of Fisheries Business Administration
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    • v.18 no.1
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    • pp.59-97
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    • 1987
  • Tuna and tuna fishing extend over most of the tropical waters of the world oceans, especially, this study of the Indian Ocean and the fish and the fishing vessels are highly mobile. No country can deal in isolation with the problems of its tuna fishery and of any tuna fishery in its waters, without collaborating with other countries. This cooperation is often best established through some formal international mechanism. The essential requirements are for information-on the resources, the fishery, the trade-and to identify where management actions are needed to consore the resources or to maintain the economic or social function of the fishery. These will also usually require some form of international mechanism. With the changes in the Law of the Sea, the siuuation in respect of management of tuna-considered among the highly migratory species, requirng special treatment-has also changed. At present there are both uncertainty regarding tuna management and political arguments as to how such management can be best implemented. Bearing this in mind, together with the fact that only few tuna stocks have shown clear evidence of serious depletion through over-exploitation, present emphasis will be placed on information requirements. This study included compiling the data necessary to review the state of stoks in the Indian Ocean tuna fishing grounds. Information on the resources-where the fish are, their quantity, their movements, etc. is important, whether in planning development of new fisheries, or considering the need for collaboration with other countries (in ascertaining to what extent their catches may affect catches of the natoinal fleet) or for conservation measures. A major source of information is the statistics of for conservation measures. A major source of information is the statistics of catch and fishing effort from existing commercial vessels. These need to be assembled for all fisheries on the same stock on an oceanwide basis. The statistical data also need to be analysed and intepreted, and combined with biological data(e.g., on growth, mortality and migration rates) to provide information that is intelligible and useful for administrators and other decision-makers. This must also be undertaken on a resource-wide or ocean-wide basis. Finally, because of the world-wide similarities in the methods of datching, processing and marketing fish, there is a particular tut not exclusive need in those countries just beginning to develop their tuna fisheries-to have ready access to a syntheis of information on tuna, tuna biology and tuna fisheries and tuna fisheries economics and management on the Indian Ocean.

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Data processing system and spatial-temporal reproducibility assessment of GloSea5 model (GloSea5 모델의 자료처리 시스템 구축 및 시·공간적 재현성평가)

  • Moon, Soojin;Han, Soohee;Choi, Kwangsoon;Song, Junghyun
    • Journal of Korea Water Resources Association
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    • v.49 no.9
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    • pp.761-771
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    • 2016
  • The GloSea5 (Global Seasonal forecasting system version 5) is provided and operated by the KMA (Korea Meteorological Administration). GloSea5 provides Forecast (FCST) and Hindcast (HCST) data and its horizontal resolution is about 60km ($0.83^{\circ}{\times}0.56^{\circ}$) in the mid-latitudes. In order to use this data in watershed-scale water management, GloSea5 needs spatial-temporal downscaling. As such, statistical downscaling was used to correct for systematic biases of variables and to improve data reliability. HCST data is provided in ensemble format, and the highest statistical correlation ($R^2=0.60$, RMSE = 88.92, NSE = 0.57) of ensemble precipitation was reported for the Yongdam Dam watershed on the #6 grid. Additionally, the original GloSea5 (600.1 mm) showed the greatest difference (-26.5%) compared to observations (816.1 mm) during the summer flood season. However, downscaled GloSea5 was shown to have only a -3.1% error rate. Most of the underestimated results corresponded to precipitation levels during the flood season and the downscaled GloSea5 showed important results of restoration in precipitation levels. Per the analysis results of spatial autocorrelation using seasonal Moran's I, the spatial distribution was shown to be statistically significant. These results can improve the uncertainty of original GloSea5 and substantiate its spatial-temporal accuracy and validity. The spatial-temporal reproducibility assessment will play a very important role as basic data for watershed-scale water management.

A Quantitative Trust Model based on Empirical Outcome Distributions and Satisfaction Degree (경험적 확률분포와 만족도에 기반한 정량적 신뢰 모델)

  • Kim, Hak-Joon;Sohn, Bong-Ki;Lee, Seung-Joo
    • The KIPS Transactions:PartB
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    • v.13B no.7 s.110
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    • pp.633-642
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    • 2006
  • In the Internet environment many interactions between many users and unknown users take place and it is usually rare to have the trust information about others. Due to the lack of trust information, entities have to take some risks in transactions with others. In this perspective, it is crucial for the entities to be equipped with functionality to accumulate and manage the trust information on other entities in order to reduce risks and uncertainty in their transactions. This paper is concerned with a quantitative computational trust model which takes into account multiple evaluation criteria and uses the recommendation from others in order to get the trust for an entity. In the proposed trust model, the trust for an entity is defined as the expectation for the entity to yield satisfactory outcomes in the given situation. Once an interaction has been made with an entity, it is assumed that outcomes are observed with respect to evaluation criteria. When the trust information is needed, the satisfaction degree, which is the probability to generate satisfactory outcomes for each evaluation criterion, is computed based on the empirical outcome outcome distributions and the entity's preference degrees on the outcomes. Then, the satisfaction degrees for evaluation criteria are aggregated into a trust value. At that time, the reputation information is also incorporated into the trust value. This paper also shows that the model could help the entities effectively choose other entities for transactions with some experiments in e-commerce.

Generation of Ionospheric Delay in Time Comparison for a Specific GEO Satellite by Using Bernese Software

  • Jeong, Kwang Seob;Lee, Young Kyu;Yang, Sung Hoon;Hwang, Sang-wook;Kim, Sanhae;Song, Kyu-Ha;Lee, Wonjin;Ko, Jae Heon
    • Journal of Positioning, Navigation, and Timing
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    • v.6 no.3
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    • pp.125-133
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    • 2017
  • Time comparison is necessary for the verification and synchronization of the clock. Two-way satellite time and frequency (TWSTFT) is a method for time comparison over long distances. This method includes errors such as atmospheric effects, satellite motion, and environmental conditions. Ionospheric delay is one of the significant time comparison error in case of the carrier-phase TWSTFT (TWCP). Global Ionosphere Map (GIM) from Center for Orbit Determination in Europe (CODE) is used to compare with Bernese. Thin shell model of the ionosphere is used for the calculation of the Ionosphere Pierce Point (IPP) between stations and a GEO satellite. Korea Research Institute of Standards and Science (KRISS) and Koganei (KGNI) stations are used, and the analysis is conducted at 29 January 2017. Vertical Total Electron Content (VTEC) which is generated by Bernese at the latitude and longitude of the receiver by processing a Receiver Independent Exchange (RINEX) observation file that is generated from the receiver has demonstrated adequacy by showing similar variation trends with the CODE GIM. Bernese also has showed the capability to produce high resolution IONosphere map EXchange (IONEX) data compared to the CODE GIM. At each station IPP, VTEC difference in two stations showed absolute maximum 3.3 and 2.3 Total Electron Content Unit (TECU) in Bernese and GIM, respectively. The ionospheric delay of the TWCP has showed maximum 5.69 and 2.54 ps from Bernese and CODE GIM, respectively. Bernese could correct up to 6.29 ps in ionospheric delay rather than using CODE GIM. The peak-to-peak value of the ionospheric delay for TWCP in Bernese is about 10 ps, and this has to be eliminated to get high precision TWCP results. The $10^{-16}$ level uncertainty of atomic clock corresponds to 10 ps for 1 day averaging time, so time synchronization performance needs less than 10 ps. Current time synchronization of a satellite and ground station is about 2 ns level, but the smaller required performance, like less than 1 ns, the better. In this perspective, since the ionospheric delay could exceed over 100 ps in a long baseline different from this short baseline case, the elimination of the ionospheric delay is thought to be important for more high precision time synchronization of a satellite and ground station. This paper showed detailed method how to eliminate ionospheric delay for TWCP, and a specific case is applied by using this technique. Anyone could apply this method to establish high precision TWCP capability, and it is possible to use other software such as GIPSYOASIS and GPSTk. This TWCP could be applied in the high precision atomic clocks and used in the ground stations of the future domestic satellite navigation system.

A Study on the Determinants of Entry Mode in the Overseas Market for Food Service Enterprises (외식기업의 해외 시장 진입 방식 결정요인에 관한 연구)

  • Lee, Jin;Han, Kyung-Soo
    • Culinary science and hospitality research
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    • v.16 no.4
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    • pp.15-27
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    • 2010
  • As most companies in the world are much interested in the overseas market as well as in the domestic market, many Korean food service enterprises came to focus on extending their branches to the overseas market. However, lack of business strategies including market research, marketing strategies, localization, etc. has made them continue to fail in market entry. The purpose of this study is to develop entry mode of determinants of Korean food service enterprises, considering their characteristic factors and environment factors in the overseas market. To do this, companies which have a head quarter in Korea and over 2 year business experience in the overseas market were chosen and used for a self-administered questionnaire survey. Statistical processing, including descriptive statistics, logistic regressing analysis, and multi regression analysis using an SPSS/PC 12.0 statistical package were conducted The result is as follows. First, explanation suitability was 85% of the entry mode in the overseas market. Second, as business size was smaller, product differentiation was higher, and CEO's will for success in the overseas market was higher, independent entry mode in the overseas market was likely to he chosen. Lastly, as the uncertainty of demand and trade barrier were lower, and a sociocultural gap was smaller, independent entry mode in the overseas market was likely to be chosen.

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Experimental Research on Radar and ESM Measurement Fusion Technique Using Probabilistic Data Association for Cooperative Target Tracking (협동 표적 추적을 위한 확률적 데이터 연관 기반 레이더 및 ESM 센서 측정치 융합 기법의 실험적 연구)

  • Lee, Sae-Woom;Kim, Eun-Chan;Jung, Hyo-Young;Kim, Gi-Sung;Kim, Ki-Seon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.5C
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    • pp.355-364
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    • 2012
  • Target processing mechanisms are necessary to collect target information, real-time data fusion, and tactical environment recognition for cooperative engagement ability. Among these mechanisms, the target tracking starts from predicting state of speed, acceleration, and location by using sensors' measurements. However, it can be a problem to give the reliability because the measurements have a certain uncertainty. Thus, a technique which uses multiple sensors is needed to detect the target and increase the reliability. Also, data fusion technique is necessary to process the data which is provided from heterogeneous sensors for target tracking. In this paper, a target tracking algorithm is proposed based on probabilistic data association(PDA) by fusing radar and ESM sensor measurements. The radar sensor's azimuth and range measurements and the ESM sensor's bearing-only measurement are associated by the measurement fusion method. After gating associated measurements, state estimation of the target is performed by PDA filter. The simulation results show that the proposed algorithm provides improved estimation under linear and circular target motions.

Effective Graph-Based Heuristics for Contingent Planning (조건부 계획수립을 위한 효과적인 그래프 기반의 휴리스틱)

  • Kim, Hyun-Sik;Kim, In-Cheol;Park, Young-Tack
    • The KIPS Transactions:PartB
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    • v.18B no.1
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    • pp.29-38
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    • 2011
  • In order to derive domain-independent heuristics from the specification of a planning problem, it is required to relax the given problem and then solve the relaxed one. In this paper, we present a new planning graph, Merged Planning Graph(MPG), and GD heuristics for solving contingent planning problems with both uncertainty about the initial state and non-deterministic action effects. The merged planning graph is an extended one to be applied to the contingent planning problems from the relaxed planning graph, which is a common means to get effective heuristics for solving the classical planning problems. In order to get heuristics for solving the contingent planning problems with sensing actions and non-deterministic actions, the new graph utilizes additionally the effect-merge relaxations of these actions as well as the traditional delete relaxations. Proceeding parallel to the forward expansion of the merged planning graph, the computation of GD heuristic excludes the unnecessary redundant cost from estimating the minimal reachability cost to achieve the overall set of goals by analyzing interdependencies among goals or subgoals. Therefore, GD heuristics have the advantage that they usually require less computation time than the overlap heuristics, but are more informative than the max and the additive heuristics. In this paper, we explain the experimental analysis to show the accuracy and the search efficiency of the GD heuristics.

Design and Implementation of a SQL based Moving Object Query Process System for Controling Transportation Vehicle (물류 차량 관제를 위한 SQL 기반 이동 객체 질의 처리 시스템의 설계 및 구현)

  • Jung, Young-Jin;Ryu, Keun-Ho
    • The KIPS Transactions:PartD
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    • v.12D no.5 s.101
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    • pp.699-708
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    • 2005
  • It becomes easy and generalized to track the cellular phone users and vehicles according to the Progress of wireless telecommunication, the spread of network, and the miniaturization of terminal devices. It has been constantly studied to provide location based services to furnish suitable services depending on the positions of customers. Various vehicle tracking and management systems are developed to utilize and manage the vehicle locations to relieve the congestion of traffic and to smooth transportation. However the designed previous work can not evaluated in real world, because most of previous work is only designed not implemented and it is developed for simple model to handle a point, a line, a polygon object. Therefore, we design a moving object query language and implement a vehicle management system to search the positions and trajectories of vehicles and to analyze the cost of transportation effectively. The designed query language based on a SQL can be utilized to get the trajectories between two specific places, the departure time, the arrival time of vehicles, and the predicted uncertainty positions, etc. In addition, the proposed moving object query language for managing transportation vehicles is useful to analyze the cost of trajectories in a variety of moving object management system containing transportation.

Bias Characteristics Analysis of Himawari-8/AHI Clear Sky Radiance Using KMA NWP Global Model (기상청 전구 수치예보모델을 활용한 Himawari-8/AHI 청천복사휘도 편차 특성 분석)

  • Kim, Boram;Shin, Inchul;Chung, Chu-Yong;Cheong, Seonghoon
    • Korean Journal of Remote Sensing
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    • v.34 no.6_1
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    • pp.1101-1117
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    • 2018
  • The clear sky radiance (CSR) is one of the baseline products of the Himawari-8 which was launched on October, 2014. The CSR contributes to numerical weather prediction (NWP) accuracy through the data assimilation; especially water vapor channel CSR has good impact on the forecast in high level atmosphere. The focus of this study is the quality analysis of the CSR of the Himawari-8 geostationary satellite. We used the operational CSR (or clear sky brightness temperature) products in JMA (Japan Meteorological Agency) as observation data; for a background field, we employed the CSR simulated using the Radiative Transfer for TOVS (RTTOV) with the atmospheric state from the global model of KMA (Korea Meteorological Administration). We investigated data characteristics and analyzed observation minus background statistics of each channel with respect to regional and seasonal variability. Overall results for the analysis period showed that the water vapor channels (6.2, 6.9, and $7.3{\mu}m$) had a positive mean bias where as the window channels(10.4, 11.2, and $12.4{\mu}m$) had a negative mean bias. The magnitude of biases and Uncertainty result varied with the regional and the seasonal conditions, thus these should be taken into account when using CSR data. This study is helpful for the pre-processing of Himawari-8/Advanced Himawari Imager (AHI) CSR data assimilation. Furthermore, this study also can contribute to preparing for the utilization of products from the Geo-Kompsat-2A (GK-2A), which will be launched in 2018 by the National Meteorological Satellite Center (NMSC) of KMA.

Opportunities and Challenges for Vietnam in AEC (AEC 출범 이후 베트남 경제의 기회와 도전)

  • Beak, Yong Hun
    • International Area Studies Review
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    • v.21 no.4
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    • pp.101-124
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    • 2017
  • This study is to examine the current situation of the AEC (ASEAN Economic Community) and analyze macroeconomic situation of Vietnam since the launch of AEC. According to recent trade indicators, Vietnam is expected to be more productive in the manufacturing and processing sectors because it is at the heart of the global value chains (GVCs) in electronics, telephones, and textiles and shoes industry. Vietnam has signed or is negotiating free trade agreements with various countries around the world including Korea, Israel, EU and RCEP and so on. Therefore, it is expected that Vietnam's trade dependency and FDI inflows to Vietnam increase more and more. However, the fact that the proportion of exports by foreign-invested companies accounts for about 70% of the total exports implies the uncertainty of Vietnam's economy in the future. Attracting FDI investment can further reduce the competitiveness of domestic companies in Vietnam. Therefore, in order for Vietnam to maintain sustainable development in the future, it is necessary to reform the momentum of foreign-invested enterprises to the development of Vietnamese companies.