The change of fishing power index was analyzed to identify the development of the vessel and gear technology that may improve the fishing efficiency of the offshore conger eel pot fishery from 1980s to 2015. Gross tonnage per fishing vessel was rapidly increased annually. The standard of pot was maintained, but the number of pot used rapidly increased by using conger eel pot hauling devices, carrying and loading devices, main line hauler, casting devices and slide type pot. Fish finder system to identify fishing ground information and the conger eel pot hauling devices were modernized, and supply rate was also increased. Therefore, the relative fishing power index in the offshore conger eel pot fishery increased from 1.0 in 1980 to 1.3 in 1990, to 1.8 in 2000 and to 2.0 in 2015. The results are expected to contribute to reasonable fisheries stock management of the offshore conger eel pot fishery.

Thousands of pelagic and demersal fishes inhabit the waters around Korea and many of them are overexploited. One of the reasons is technological development, which increases the efficiency of the vessels continuously. The analysis was conducted to identify the change of fishing power index to develop the vessel and gear technology that may have improved the fishing efficiency of the otter trawl fishery from 1960s to 2010s. Gross tonnage was decreased stably, but horse power was increased annually. The perimeter of net mouth was somewhat longer, but little changed. Color fish finder was utilized from the mid-1960s. Hydraulic net drum were introduced in the early 1990s, and supply rate was gradually increased. Surveys on the supply and upgrading of fishing equipment utilized visiting research. Therefore, the relative fishing power index in the trawl fishery increased about two to three times in the 2010s compared to the 1980s. The results are expected to contribute to reasonable fisheries stock management.

Thousands of demersal fishes inhabit in the waters around Korea and most of them are overexploited. One of reasons is technological development, which increases the efficiency of the vessels continuously. The analysis was conducted to identify the change of fishing power index to develop the vessel and gear technology that may have improved the fishing efficiency of the Danish seine fishery from 1960s to 2010s. Gross tonnage was decreased stably, but the horse power was increased annually. The length of ground rope, warp and hand rope was somewhat longer, but changed a little. Color fish finder was utilized from the mid-1960s and positioning system was used five years later. A hydraulic line hauler were introduced in the mid-1980s, and supply rate was gradually increased. Surveys on the supply and upgrading of fishing equipment utilized visiting researchers. Therefore, the relative fishing power index in the Danish seine fishery increased stably from 1.0 in 1970 to 1.0 in 1980, to 1.2 in 1990, to 1.3 in 2000 and to 1.3 in 2010. The results are expected to contribute to reasonable fisheries stock management.

The small yellow croaker (Larimichthys polyactis) is one of the representative high-class fish species in Korea. The catch of small yellow croaker in adjacent water fisheries has been continuously decreasing from 59,226 tons in 2011 to 19,271 tons in 2016. The small yellow croaker is caught by gillnet, stow net and bottom trawl, among which about 55~65% is caught by gillnet. For the sustainable use of small yellow croaker, the fishing power of small yellow croaker drift gillnet is very important. Therefore, the change of fishing power index were analyzed to identify the development of the vessel and gear technology that may have improved the fishing efficiency of the small yellow croaker drift gillnet fishery from 1960s to 2010s. Gross tonnage and horse power per fishing vessel was increased annually. The mesh size was 75.0 mm in the 1960s, but reduced to 60.6 mm in the 1980s and to 51.0 mm in the 2000s. In the 1960s, it was hauled out by manpower. However, the net hauler were modernized and supply rate was also increased since 1970. Due to the mechanization of the net hauler, the number (length) of used net gradually increased from 1.5 km in the 1960s to 7.5 km in the mid-1980s and to 15 km in 2010. Colour fish finders and positioning system were introduced and utilized from the mid-1980s. Surveys on the supply and upgrading of fishing equipment utilized visiting research. Therefore, the relative fishing power index in the small yellow croaker drift gillnet fishery increased from 1.0 in 1980 to 0.8 in 1970, to 1.1 in 1990, to 1.6 in 2000 and to 1.9 in 2010. The results are expected to contribute to reasonable fisheries stock management of the small yellow croaker drift gillnet fishery.

High variance observed in the measurement system can cause high process variation that can affect process capability badly. Therefore, measurement system analysis is closely related to process capability analysis. Generally, the evaluation for measurement system and process variance is performed separately in the industry. That is, the measurement system analysis is implemented before process monitoring, process capability and process performance analysis even though these analyses are closely related. This paper presents the effective concurrent evaluation procedure for measurement system analysis and process capability analysis using the table that contains Process Performance (Pp), Gage Repeatability & Reproducibility (%R&R) and Number of Distinct Categories (NDC). Furthermore, the long-term process capability index (Pp), which takes into account both gage variance and process variance, is used instead of the short-term process capability (Cp) considering only process variance. The long-term capability index can reflect well the relationship between the measurement system and process capability. The quality measurement and improvement guidelines by region scale are also described in detail. In conclusion, this research proposes the procedure that can execute the measurement system analysis and process capability analysis at the same time. The proposed procedure can contribute to reduction of the measurement staff’s effort and to improvement of accurate evaluation.

Squid is one of the important fisheries resources in Korea. Therefore, squid has been designated and managed as a target species of total allowable catch (TAC) since 2007, but the catch amount is gradually decreasing. The analysis was conducted to identify the change of relative fishing power index to develop the vessel and gear technology that may have improved the fishing efficiency of the offshore squid jigging fishery from 1960s to 2010s. Gross tonnage per fishing vessel increased with the increase in size until 1990, but then gradually decreased to 41.0 tons in 2000 and 37.1 tons in 2010. The illuminating power (energy consumption) by fishing lamps increased to 180 kW in 2005 and stabilized to 120 kW in 2015. Jigging machine started to be supplied to fishing vessels from the early 1970s, and fish finders began to be supplied in the early 1980s and gradually increased. Therefore, the relative fishing power index in the offshore squid jigging fishery increased from 1.0 in 1980 to 1.1 in 1990, to 3.5 in 2000 and to 2.5 in 2010, but the increment rate slowed down gradually. The results are expected to contribute to reasonable fisheries stock management.

선박의 안전 확보를 위해 준수해야 하는 IMO 복원성 규칙에는 복원정 곡선(GZ Curve) 등에 관한 내용이 다양하게 규정되어 있다. 이 IMO 복원성 규정에는 다양한 항목의 만족 기준이 제시되고 있으나, 선박을 운항하는 선장에게 선박의 복원성능을 종합적이며, 간편하게 제공할 수 있는 방법은 부재한 상황이다. 이를 위해 본 연구에서는 복원성을 하나의 값으로 표현할 수 있는 지수를 개발하였다. IMO에서 규정한 선박의 6가지 복원성 항목과 대상선박의 적재상황에 따른 복원성 계산결과를 바탕으로 지수산정식이 도출되었다. 또한 개발된 지수산정식을 적용하여 다양한 화물 적재 상황별 복원성 지수(Stability Index)를 계산하였으며, 복원성능의 전반적인 정도를 수치적으로 적절하게 설명할 수 있음을 검증하였다. 이는 선박의 선장에게 복원성 평가하고 판단하는데 도움을 줄 것으로 판단된다.

Lots of fishery stocks are overexploited and the overcapacity exists in Korean fishing fleets. One of the reasons is technological development, which increases the efficiency of the vessels continuously. The analysis was conducted to identify the change of fishing power index to develop the vessel and gear technology that may have improved the fishing efficiency of the offshore large powered purse seine fishery from 1960s to 2010s. Gross tonnage and horse power per fishing vessel was increased annually. Fishing gear material was changed to the knotless webbing to settle faster. Fishing equipments was modernized and supply rate was also increased. Therefore the relative fishing power index in the offshore large powered purse seine fishery increased from 0.4 in 1970 to 1.0 in 1980, to 1.5 in 2000 and to 1.6 in 2010, but the rate of increase slowed down gradually. The results are expected to contribute to reasonable fishery stock management.

An estimation of indices for potential process capability (Cpk) and/or overall process performance (Ppk) is considered in order to gain insight into the statistical process control. The similarity and the difference of the two indices are discussed in some detail to clarify the meaning and usage of the two indices. It is demonstrated that the short term variance can be estimated within the framework of analysis of variance (ANOVA). Theoretic background is examined and followed by a simple numerical example, with a view to the implementation of the concept in the industrial fields.

Fishing power, which means performance of fishing vessel or catchability of fishing gear, can explain using by fishing power index(FPI) to compare fishery efficiency among uniformity types of fishery that work during the fixed period in specific fishing ground. This research analyzed on their fishing power and catchability using comparing each sampled vessels of coastal trap fishery for common octopus. The results showed that they were no difference in amount of used trap and immersed time etc. in CPUE among sampled vessels, and had no correlation of catch production due to vessel's tonnage. Most vessel's FPI estimates but 3 vessels were higher than the averaged, and showed similar fishing power in general. And then, CPUE and FPI showed that 4 to 5 tonnage vessels would be superior to another, 4 tonnage vessels had also good catchability. Therefore, we estimated that 4 tonnage vessels had the most efficiency work for coastal trap fishery for common octopus.

When a ship is course-keeping in the open seas, autopilot system is adapted. The design of autopilot system is very important for improvement of ship′s element research. Automatic steering system consists of autopilot device, power unit, steering gear, magnetic or gyro compass and ship dynamics. In order to evaluate automatic steering system of ships in open seas. we need to know the characteristics of each component of the system, and also to know the characteristics of disturbance to ship dynamics. In this paper, I provide evaluation method of autopilot navigation system of the fishing ship. Prediction method based on the principle of linear superposition is introduced for irregular disturbance. For the evaluation of automatic steering system of a ship, "performance index" is introduced from the viewpoint of energy saving and calculation method is frequency response analysis. Finally, I carried out calculation of sensitivity of control constants of autopilot with various conditions of ocean environments.

본 논문은, 시설물안전법의 적용을 받지 않아 안전사각 지대에 놓여 있는 중소규모 교량들의 유지관리 전략 수립시 기초자료로 활용할 수 있는, 중소규모 교량 성능평가 우선순위 결정 방안을 제시하기 위해 실시하였다. 이를 위해 취약도와 영향도를 기반으로 하는 위험도 지수를 산출하고, 산출된 위험도 지수에 따라 이들 교량들을 성능평가 즉시실시교량, 단기실시교량 및 관찰교량으로 구분하여 제안하고, 실제 공용중에 있는 중소규모 교량에 적용하여 제안한 방안의 현장 적용성을 확인하였다. 연구결과, 여기서 제시된 방안은 향후 중소규모 교량의 유지관리 전략 수립에 적절히 활용되어 중소규모교량 사고 방지 및 유지관리 예산절감에 기여할 수 있을 것으로 판단되었다.