• Title/Summary/Keyword: Fairway

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Study on the Fairway Used by Coastal Passenger Ship at Mokpo Port (목포항 입출항 연안여객선의 이용 항로에 관한 고찰)

  • Lee, Li-Na;Lee, Hong-Hoon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.4
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    • pp.525-532
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    • 2022
  • The port of Mokpo operates the largest number of coastal passenger ships and routes in Korea. These coastal passenger ships pass through narrow channels in the south-west coast of Korea owing to the geographical effect. It is difficult to find a research for the safety of the marine traffic environment in the narrow channel used by coastal passenger ship. Therefore, in this study, the navigation safety of the target coastal passenger ship was analyzed in the narrow channel near the port of Mokpo using the Korea design standard for port and harbour facilities. As a result of the analysis, the width of the narrow channel between Maek-island and Dali-island is narrower than 1.5 times of the target ship's length over all, the degree of curvature of the narrow channel exceeds the standard value of 30°, and several fishing gears exist near the narrow channel. Finally, the following were suggested to improve the safety of navigation on the narrow channel: keeping one-way traffic during the day-time, and navigating through the designated fairway during night·visibility restriction·low tide.

Selecting Ordering Policy and Items Classification Based on Canonical Correlation and Cluster Analysis

  • Nagasawa, Keisuke;Irohara, Takashi;Matoba, Yosuke;Liu, Shuling
    • Industrial Engineering and Management Systems
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    • v.11 no.2
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    • pp.134-141
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    • 2012
  • It is difficult to find an appropriate ordering policy for a many types of items. One of the reasons for this difficulty is that each item has a different demand trend. We will classify items by shipment trend and then decide the ordering policy for each item category. In this study, we indicate that categorizing items from their statistical characteristics leads to an ordering policy suitable for that category. We analyze the ordering policy and shipment trend and propose a new method for selecting the ordering policy which is based on finding the strongest relation between the classification of the items and the ordering policy. In our numerical experiment, from actual shipment data of about 5,000 items over the past year, we calculated many statistics that represent the trend of each item. Next, we applied the canonical correlation analysis between the evaluations of ordering policies and the various statistics. Furthermore, we applied the cluster analysis on the statistics concerning the performance of ordering policies. Finally, we separate items into several categories and show that the appropriate ordering policies are different for each category.

Applying Genetic Algorithm for Can-Order Policies in the Joint Replenishment Problem

  • Nagasawa, Keisuke;Irohara, Takashi;Matoba, Yosuke;Liu, Shuling
    • Industrial Engineering and Management Systems
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    • v.14 no.1
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    • pp.1-10
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    • 2015
  • In this paper, we consider multi-item inventory management. When managing a multi-item inventory, we coordinate replenishment orders of items supplied by the same supplier. The associated problem is called the joint replenishment problem (JRP). One often-used approach to the JRP is to apply a can-order policy. Under a can-order policy, some items are re-ordered when their inventory level drops to or below their re-order level, and any other item with an inventory level at or below its can-order level can be included in this order. In the present paper, we propose a method for finding the optimal parameter of a can-order policy, the can-order level, for each item in a lost-sales model. The main objectives in our model are minimizing the number of ordering, inventory, and shortage (i.e., lost-sales) respectively, compared with the conventional JRP, in which the objective is to minimize total cost. In order to solve this multi-objective optimization problem, we apply a genetic algorithm. In a numerical experiment using actual shipment data, we simulate the proposed model and compare the results with those of other methods.

Spatial and Temporal Distribution of Chestnut Brown Chafer, Adoretus tenuimaculatus (Coleoptera: Scarabaeidae) in Golf Courses (주둥무늬차색풍뎅이(Adoretus tenuimaculatus)의 산란지 선호성과 골프장에서의 분포)

  • 이동운;추호렬;이태우;박지웅;권태웅
    • Asian Journal of Turfgrass Science
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    • v.13 no.2
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    • pp.113-124
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    • 1999
  • This study was carried out to know the oviposition preference site of chestnut brown chafer ( CBC ), Adoretus tenuimaculatus and its temporal activity and spatial distribution in green. Larval distribution was also investigated in golf courses for the control of CBC. CBC collected from Yongwon Golf Club in Chinhae, Tongdo Golf Club in Yangsan, Gyeongsan Province, Daegu Golf Club in Gyeongsan, Kyeongbuk Province, Dongrae Golf Club laid more eggs on broableaf of Zoysia matrella than Z. japonica, broadleaf+middleleaf of Z. matrella, Poa pratensis, and P. annua. The number of CBC egg was $19.7\pm$6.7 in Z. japonica,$ 1.7\pm$1.5 in P. pratensis, $1.3\pm$1.5 in sandy loam and $5.7\pm$2.9 in sand. Acitivity time of CBC in a day was the peak at 20:00 and continued to 24:00. CBCs adults were more collected from outside of golf courses whichhad many host plants than roadside courses. Density of white grubs was significantly different in fairway only. CBCs were more collected at tee and fairway than green. Density of white grubs was $54.6\pm$100 in broadleaf of Z. matellia and $37.7\pm$33.8 in P. pratensis at the back tee of the 7th hole in Dongrae Golf Club.

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A Review on the Characteristics of Environmental Stress Model for Maritime Traffic Safety Assessment (해상교통 안전성 평가를 위한 환경 스트레스 모델의 특성 고찰(I))

  • Gong, In-Young
    • Journal of Navigation and Port Research
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    • v.27 no.5
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    • pp.479-486
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    • 2003
  • The concept of “Environmental Stress(ES)” can be used as a useful index when assessing the maritime traffic safety. It is composed of two parts, one due to geographical restriction and another one due to traffic congestion. In this paper, Environmental Stress due to geographical restriction is reviewed Its characteristics are surveyed from the sample calculation results for some hypothetical cases, such as approaching a breakwater, navigating in a long straight channel, and in a long bended channel. Sample calculations are also carried out for the approach channels in Busan and Kwangyang harbor. By using this ES concept, it is expected that objective ana quantitative assessment of safety is possible for various environmental conditions when navigating in a harbor or in a fairway.

A Study on Traffic Safety Assessment at Pyeongtack Port by Ship handling Simulator (선박조종시뮬레이터를 이용한 평택항 통항 안전성 평가)

  • Kim, Se-Won;Gug, Seung-Gi;Kim, Won-Ouk;Park, Yeong-Su;Jo, Keoung-Min
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.29 no.1
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    • pp.85-93
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    • 2005
  • In order to effective transportation of goods & smooth traffic in west sea area, it is a plan to build Pyeongtaek bridge. Basically ship-handling operators have a mental difficulty and hazardous for navigation under bridge which is constructed across on the fairway. Therefore this study aims to propose the traffic safety assessment of navigation under the bridge by using full mission ship-handling simulator and also investigate the bridge design regulations of certain countries on the fairway.

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Genetic Algorithm-Based Coordinated Replenishment in Multi-Item Inventory Control

  • Nagasawa, Keisuke;Irohara, Takashi;Matoba, Yosuke;Liu, Shuling
    • Industrial Engineering and Management Systems
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    • v.12 no.3
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    • pp.172-180
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    • 2013
  • We herein consider a stochastic multi-item inventory management problem in which a warehouse sells multiple items with stochastic demand and periodic replenishment from a supplier. Inventory management requires the timing and amounts of orders to be determined. For inventory replenishment, trucks of finite capacity are available. Most inventory management models consider either a single item or assume that multiple items are ordered independently, and whether there is sufficient space in trucks. The order cost is commonly calculated based on the number of carriers and the usage fees of carriers. In this situation, we can reduce future shipments by supplementing items to an order, even if the item is not scheduled to be ordered. On the other hand, we can reduce the average number of items in storage by reducing the order volume and at the risk of running out of stock. The primary variables of interest in the present research are the average number of items in storage, the stock-out volume, and the number of carriers used. We formulate this problem as a multi-objective optimization problem. In a numerical experiment based on actual shipment data, we consider the item shipping characteristics and simulate the warehouse replenishing items coordinately. The results of the simulation indicate that applying a conventional ordering policy individually will not provide effective inventory management.

A Study on the Improvement of Marine Traffic System in the Ulsan Approaching Waters (울산항 접근수역의 항로지정에 관한 연구)

  • Jeong, Jae-Yong;Yoon, Dae-Gwun;Kim, Cheol-Seung
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.16 no.2
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    • pp.209-214
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    • 2010
  • This study examined environmental condition, marine accidental data, marine traffic capacity and traffic flow, and fisheries zone status near Ulsan approaching water area. A questionnaire survey of marine traffic system was conducted on experts and users, and new plan was proposed. On the basis of the responses of experts and users to questionnaire, the essential factor of navigation danger and the essential factor of collision risk as well as the improvement plans were proposed. More efficient navigational fairway was set up through this study.

A Review on the Characteristics of Environmental Stress Model for Maritime Traffic Safety Assessment (해상교통 안전성 평가를 위한 환경 스트레스 모델의 특성 고찰(I))

  • 공인영
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2003.05a
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    • pp.198-205
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    • 2003
  • The concept “Environmental Stress(ES)” can be used as a useful index when assessing the maritime traffic safety. It is composed of two parts, one due to geographical restriction and another one due to traffic congestion. In this paper, Environmental Stress due to geographical restriction is reviewed. Its characteristics are surveyed from the sample calculation results for some hypothetical cases, such as approaching a breakwater, navigating in a long straight channel, and in a long bended channel. Sample calculations are also carried out for the approach channels in Busan and Kwangyang harbor. By using this ES concept. it is expected that objective and quantitative assessment of safety is possible for various environmental conditions when navigating in a harbor or in a fairway.

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A Three-year Study on the Leaf and Soil Nitrogen Contents Influenced by Irrigation Frequency, Clipping Return or Removal and Nitrogen Rate in a Creeping Bentgrass Fairway (크리핑 벤트그라스 훼어웨이에서 관수회수.예지물과 질소시비수준이 엽조직 및 토양 질소함유량에 미치는 효과)

  • 김경남;로버트쉬어만
    • Asian Journal of Turfgrass Science
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    • v.11 no.2
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    • pp.105-115
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    • 1997
  • Responses of 'Penncross' creeping bentgrass turf to various fairway cultural practices are not well-established or supported by research results. This study was initiated to evaluate the effects of irrigation frequency, clipping return or removal, and nitrogen rate on leaf and soil nitrogen con-tent in the 'Penncross' creeping bentgrass (Agrostis palustris Huds.) turf. A 'Penncross' creeping bentgrass turf was established in 1988 on a Sharpsburg silty-clay loam (Typic Argiudoll). The experiment was conducted from 1989 to 1991 under nontraffic conditions. A split-split-plot experimental design was used. Daily or biweekly irrigation, clipping return or removal, and 5, 15, or 25 g N $m-^2$ $yr-^1$ were the main-, sub-, and sub-sub-plot treatments, respectively. Treatments were replicated 3 times in a randomized complete block design. The turf was mowed 4 times weekly at a l3 mm height of cut. Leaf tissue nitrogen content was analyzed twice in 1989 and three times in both 1990 and 1991. Leaf samples were collected from turfgrass plants in the treatment plots, dried immediately at 70˚C for 48 hours, and evaluated for total-N content, using the Kjeldahl method. Concurrently, six soil cores (18mm diam. by 200 mm depth) were collected, air dried, and analyzed for total-N content. Nitrogen analysis on the soil and leaf samples were made in the Soil and Plant Analyical Laboratory, at the University of Nebraska, Lincoln, USA. Data were analyzed as a split-split-plot with analysis of variance (ANOVA), using the General Linear Model procedures of the Statistical Analysis System. The nitrogen content of the leaf tissue is variable in creeping bentgrass fairway turf with clip-ping recycles, nitrogen application rate and time after establishment. Leaf tissue nitrogen content increased with clipping return and nitrogen rate. Plots treated with clipping return had 8% and 5% more nitrogen content in the leaf tissue in 1989 and 1990, respectively, as compared to plots treated with clipping removal. Plots applied with high-N level (25g N $m-^2$ $yr-^1$)had 10%, 17%, and 13% more nitrogen content in leaf tissue in 1989, 1990, and 1991, respectively, when compared with plots applied with low-N level (5g N $m-^2$ $yr-^1$). Overall observations during the study indicated that leaf tissue nitrogen content increased at any nitrogen rate with time after establishment. At the low-N level treatment (5g N $m-^2$ $yr-^1$ ), plots sampled in 1991 had 15% more leaf nitrogen content, as compared to plots sampled in 1989. Similar responses were also found from the high-N level treatment (25g N $m-^2$ $yr-^1$ ).Plots analyzed in 1991 were 18% higher than that of plots analyzed in 1989. No significant treatment effects were observed for soil nitrogen content over the first 3 years after establishment. Strategic management application is necessary for the golf course turf, depending on whether clippings return or not. Different approaches should be addressed to turf fertilization program from a standpoint of clipping recycles. It is recommended that regular analysis of the soil and leaf tissue of golf course turf must be made and fertilization program should be developed through the interpretation of its analytic data result. In golf courses where clippings are recycled, the fertilization program need to be adjusted, being 20% to 30% less nitrogen input over the clipping-removed areas. Key words: Agrostis palustris Huds., 'Penncross' creeping bentgrass fairway, Irrigation frequency, Clipping return, Nitrogen rate, Leaf nitrogen content, Soil nitrogen content.

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