• Title/Summary/Keyword: helm

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Maneuverabilities of Skipjack Pole and Liner (가다랑어 채낚기 어선의 조종 성능에 관한 연구)

  • 김기윤
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.18 no.2
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    • pp.77-80
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    • 1982
  • The maneuverabilities of 240 GT class skipjack pole and liner were studied, based on the maneuvering indices and the data which were obtained from Z test of the experimental ship, the m.s. KWANACKSAN, the training ship of the National Fisheries University of Busan. The maneuvering indices K' of the experimental ship were 0.611(at 10$^{\circ}$Z test), 0.622(at 20$^{\circ}$Z test) and 0.556(at 30$^{\circ}$Z test). Her maneuvering indices T' were 1.094(at 10$^{\circ}$Z test), 1.695(at 20$^{\circ}$Z test) and 1.367(at 30$^{\circ}$Z test). The above calculated values K', T' showed that her turning ability at helm angle 20$^{\circ}$ and her obeying ability at helm angle 10$^{\circ}$ were most effective. As it appeared that the calculated K'-values of the experimental ship were smaller than the standard K'-values of different kinds of ships and her overshoot angles at her Z test were greater than those of them, her turning ability was found to be lower. When the experimental ship took a turn at her 10$^{\circ}$Z test, running distance was about 8.3 times her own length and didn't exceed the standard maneuvering distance, 5 to 11 times ship's own length, therefore she was considered to have good maneuverabilities synthetically.

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A Study on Phrygia Headgear (프리기아[Phrygia] 모자에 대한 연구)

  • Yi-Chang Youngsoo
    • Journal of the Korean Society of Costume
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    • v.55 no.4 s.94
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    • pp.138-150
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    • 2005
  • Phrygia headgear has an important meaning from the perspectives of costume history and cultural exchanges in ancient times. This study is to investigate the prototype of Phrygia headgear through analysis of its manufacturing methods and styles on the basis of prior studies on ancient sculptures and literatures conducted by European researchers and to examine its history and meanings. In these ways, this study will be helpful in understanding the importance of Phrygia headgear in cultural exchanges between the East and the West. Results of this study can be summarized as follows: Phrygia headgear was orn by eastern tribes, so it was a symbol of those from the east in ancient times. Phrygia headgear is frequently found in Greek artistic works of 5th to 4th century BC that depicted eastern tribes. Also, this headgear can be observed in artistic works for Mithras, Attis, or other gods. Since Phrygia headgear's shape is similar to that of Homer's helm, many researchers believe that it might be originated from Homer's helm. This headgear made of oxen scrotum(stierbeutel) or its surrounding skin has a long end at the top. This long end is round and drooping toward the front side. From such unique shape, we top. This long end is round and drooping toward the front side. From such unique shape, we top. This long end is round and drooping toward the front side. From such unique shape, we can draw a conclusion that Phrygia headgear was made of oxen scrotum and its surrounding skin. Dependingy on drooping patterns, there are various shapes, such as the round, tightly swollen one worn by Mithras, the tongue-shaped one found in Basilika S. Apolinare Nuovo's mosaic depicting three wise men, the balloon-shaped one frequently found in Greek vases depicting Scythian, and the one drooping to the side depicted in Alexandersarkophag. Further, some Phrygia headgear has covers for neck and ears. For example, Phrygia headgear worn by Persian Satrap tribe has such covers attached to the head part. Meanwhile, Phrygia headgear worn by Amazone tribe does not show such separate covers, Rather, one piece of oxen skin was tanned and finished to make such covers. Wearing Phrygia headgear can be interpreted in several ways. Use of animal's skin for wearing things is a unique aspect in ancient societies because they believed that wearing animal skin would give them power of the animal. Further, Phrygia headgear made of oxen scrotum was a symbol of reproductive power to women.

Influence of preserved brewing yeast strains on fermentation behavior and flocculation capacity

  • Cheong, Chul;Wackerbauer, Karl;Beckmann, Martin;Kang, Soon-Ah
    • Nutrition Research and Practice
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    • v.1 no.4
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    • pp.260-265
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    • 2007
  • Preservation methods on the physiological and brewing technical characters in bottom and top brewing yeast strains were investigated. The preserved yeasts were reactivated after 24 months storage and grown up to stationary phase. The samples of filter paper storage indicated a higher cell growth and viability during propagation than those of nitrogen and lyophilization storage independent on propagation temperature. In addition, the filter paper storage demonstrated a faster absorption of free amino nitrogen and a highest level of higher aliphatic alcohols production during propagation than other preservation methods, which can be attributed to intensive cell growth during propagation. Moreover, the filter paper storage showed a faster accumulation for glycogen and trehalose during propagation, whereas, in particular, lyophilization storage noted a longer adaptation time regarding synthesis of glycogen and trehalose with delayed cell growth. In beer analysis, the filter paper storage formed an increased higher aliphatic alcohols than control. In conclusion, the preservation of filter paper affected positively on yeast growth, viability and beer quality independent on propagation temperature. In addition, in this study, it was obtained that the HICF and Helm-test can be involved as rapid methods for determination of flocculation capacity.

Safety Helmet Capable of Indicating the Worker's Risk Indices (근로자의 위험지수를 표시하는 안전모)

  • Gu, Jong-Hwa;Lee, Ho-Hyun;Lee, Kang-Suk;Chun, Myung-Geun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.67 no.2
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    • pp.106-111
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    • 2018
  • Recently, due to the effect of global warming, the high temperature phenomenon continues, and the time for workers exposed to high temperature, cold and infrared is increasing and then safety is threatened. Due to the nature of on-site work, the work is being carried out in an unreasonable manner due to the process, which is exposed to disasters due to high temperature and cold. Even though the injured skin may be damaged, the worker may not be aware of it and may be injured. By understanding the working environment of the worker and calculating the risk index and expressing it on the helmet, the surrounding colleagues inform the worker of the risk and take appropriate measures so that the accident can be prevented in advance. This study was conducted to investigate the effect of exposure duration on the workers' by measuring the exposure time, the risk index is displayed in the form of a traffic light to the helm, informing neighboring workers and managers, and transmitting to the workers by voice.

The Effectiveness of MOOS-IvP based Design of Control System for Unmanned Underwater Vehicles (MOOS-IvP를 이용한 무인잠수정 제어기 개발의 효용성)

  • Kim, Jiyeon;Lee, Dongik
    • IEMEK Journal of Embedded Systems and Applications
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    • v.9 no.3
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    • pp.157-163
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    • 2014
  • This paper demonstrates the benefit of using MOOS-IvP in the development of control system for Unmanned Underwater Vehicles(UUV). The demand for autonomy in UUVs has significantly increased due to the complexity in missions to be performed. Furthermore, the increased number of sensors and actuators that are interconnected through a network has introduced a need for a middleware platform for UUVs. In this context, MOOS-IvP, which is an open source software architecture, has been developed by several researchers from MIT, Oxford University, and NUWC. The MOOS software is a communication middleware based on the publish-subscribe architecture allowing each application to communicate through a MOOS database. The IvP Helm, which is one of the MOOS modules, publishes vehicle commands using multi-objective optimization in order to implement autonomous decision making. This paper explores the benefit of MOOS-IvP in the development of control software for UUVs by using a case study with an auto depth control system based on self-organizing fuzzy logic control. The simulation results show that the design and verification of UUV control software based on MOOS-IvP can be carried out quickly and efficiently thanks to the reuse of source codes, modular-based architecture, and the high level of scalability.

ON PAIR MEAN CORDIAL GRAPHS

  • R. PONRAJ;S. PRABHU
    • Journal of Applied and Pure Mathematics
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    • v.5 no.3_4
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    • pp.237-253
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    • 2023
  • Let a graph G = (V, E) be a (p, q) graph. Define $${\rho}=\{\array{{\frac{p}{2}} & \;\;p\text{ is even} \\ {\frac{p-1}{2}} & \;\;p\text{ is odd,}$$ and M = {±1, ±2, … ± ρ} called the set of labels. Consider a mapping λ : V → M by assigning different labels in M to the different elements of V when p is even and different labels in M to p - 1 elements of V and repeating a label for the remaining one vertex when p is odd. The labeling as defined above is said to be a pair mean cordial labeling if for each edge uv of G, there exists a labeling ${\frac{{\lambda}(u)+{\lambda}(v)}{2}}$ if λ(u) + λ(v) is even and ${\frac{{\lambda}(u)+{\lambda}(v)+1}{2}}$ if λ(u) + λ(v) is odd such that ${\mid}{\bar{{\mathbb{S}}}}_{\lambda}{_1}-{\bar{{\mathbb{S}}}}_{{\lambda}^c_1}{\mid}{\leq}1$ where ${\bar{{\mathbb{S}}}}_{\lambda}{_1}$ and ${\bar{{\mathbb{S}}}}_{{\lambda}^c_1}$ respectively denote the number of edges labeled with 1 and the number of edges not labeled with 1. A graph G for which there exists a pair mean cordial labeling is called a pair mean cordial graph. In this paper, we investigate the pair mean cordial labeling behavior of few graphs including the closed helm graph, web graph, jewel graph, sunflower graph, flower graph, tadpole graph, dumbbell graph, umbrella graph, butterfly graph, jelly fish, triangular book graph, quadrilateral book graph.

The Effect of the Speed of a Ship on Her Turning Circle (선속이 선회권에 미치는 영향에 관한 연구)

  • 김기윤
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.3
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    • pp.209-214
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    • 1999
  • The turning circle of a ship is the path followed by her center of gravity in making a turn of 360$^{\circ}$degrees or more with helm at constant angle. But generally it means her path traced at full angle of the rudder. For the ordinary ship the bow will be inside and the stern outside this circle.It has been usually understood that the turning circle is not essentinally affected by ship's speed at Froude numbers less than about 0.30. However, it is recently reported that the speed provide considerable effects upon the turning circle in piloting many ships actually at sea. In this paper, the author analyzed what effects the speed could provide on the turning circle theoretically from the viewpoint of ship motions and examined how the alteration of the speed at Froude no. under 0.30 affect the turning circle actually, through experiments of actual ships of a small and large size.The main results were as follows.1. Even though ship's speed at Froude no. under 0.30, the alteration of the speed affects the turning circle considerably.2. When the full ahead speeds at Froude no. under 0.30 of small and large ships were increased about 3 times slow ahead speeds, the mean rates of increase of the advances, tactical diameters and final diameters of thease ships were about 16%, 21% and 19% respectively.3. When the full ahead speeds at Froued no. under 0.30 of small and large ships were increased about 3 times slow ahead speed, the mean rate of increase of the turning circle elements of large ships was greater 10% than that of small ships. 4. When the full ahead speeds at Froued no. under 0.30 of small and large ships were increased about 3times slow ahead speeds, the mean rates of increase of the tactical diameter and final diameter of thease ships were greater than that of the advances of thease ships. 5. When only alteration of speed or sip's head turning is the effective action to avoid navigational fixed hagards, reducing the speed is always more advantageous than increasing the speed in order to shorten fore or transverse distance.

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The Effect of the Speed of a Ship on Her Turning Circle (선속이 선회권에 미치는 영향에 관한 연구)

  • 김기윤
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.3
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    • pp.210-210
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    • 1999
  • The turning circle of a ship is the path followed by her center of gravity in making a turn of 360$^{\circ}$degrees or more with helm at constant angle. But generally it means her path traced at full angle of the rudder. For the ordinary ship the bow will be inside and the stern outside this circle.It has been usually understood that the turning circle is not essentinally affected by ship's speed at Froude numbers less than about 0.30. However, it is recently reported that the speed provide considerable effects upon the turning circle in piloting many ships actually at sea. In this paper, the author analyzed what effects the speed could provide on the turning circle theoretically from the viewpoint of ship motions and examined how the alteration of the speed at Froude no. under 0.30 affect the turning circle actually, through experiments of actual ships of a small and large size.The main results were as follows.1. Even though ship's speed at Froude no. under 0.30, the alteration of the speed affects the turning circle considerably.2. When the full ahead speeds at Froude no. under 0.30 of small and large ships were increased about 3 times slow ahead speeds, the mean rates of increase of the advances, tactical diameters and final diameters of thease ships were about 16%, 21% and 19% respectively.3. When the full ahead speeds at Froued no. under 0.30 of small and large ships were increased about 3 times slow ahead speed, the mean rate of increase of the turning circle elements of large ships was greater 10% than that of small ships. 4. When the full ahead speeds at Froued no. under 0.30 of small and large ships were increased about 3times slow ahead speeds, the mean rates of increase of the tactical diameter and final diameter of thease ships were greater than that of the advances of thease ships. 5. When only alteration of speed or sip's head turning is the effective action to avoid navigational fixed hagards, reducing the speed is always more advantageous than increasing the speed in order to shorten fore or transverse distance.

Viruses, Bacteria and Helminths of Invasive Carp: Insights from an In Vitro Assay and a Survey with Native Fishes in a Large Midwestern River

  • Thurner, Kensey;Goforth, Reuben R.;Chen, Shuai;Amberg, Jon;Leis, Eric;Kinsella, John M.;Mahapatra, Cecon;Sepulveda, Maria S.
    • Journal of fish pathology
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    • v.30 no.2
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    • pp.135-148
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    • 2017
  • Pathogen introductions associated with aquatic invasive species threaten ecosystems and biodiversity worldwide. Bigheaded carps (BHC), including Silver Carp Hypophthalmichthys molitrix, Bighead Carp H. nobilis, and their hybrids, are prolific, invasive pests in central US rivers. However, little is known about pathogen effects on invading BHC or how BHC affect the disease risk profile for native fishes in receiving ecosystems. We therefore conducted, from May 2013-December 2014, a systematic pathogen survey for BHC and native fishes in the Wabash River watershed, Indiana, USA. We found Pseudomonas fluorescens, P. putida, and Salmonella enterica DNA in BHC as well as native fishes, although none of these bacteria were exclusively present in BHC. DNA from other bacterial taxa was detected only in native fishes and Common Carp Cyprinus carpio. No gastrointestinal helminths were detected in BHC, although they were common in most native fishes examined. We also conducted in vitro studies on BHC tissues (skin, gill, fin, and fry) and found high sensitivity to Largemouth Bass virus, viral hemorrhagic septicemia virus, and infectious pancreatic necrosis virus. We conclude that BHC are not heavily burdened by bacteria, viruses and parasites in the invaded study ecosystems, although they do harbor native bacteria and show potential for high sensitivity to endemic viruses.

Analysis the factors on the capsize of passenger vessel Sewol (여객선 세월호의 전복 요인 분석)

  • KIM, Jung-Chang;KANG, Il-Kwon;HAM, Sang-Jun;PARK, Chi-Wan
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.51 no.4
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    • pp.512-519
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    • 2015
  • A historical tragic disaster happened by capsizing the passenger ship Sewol at South Western Sea of Korea in 16, April 2014. The ship which left Incheon harbour to bound for Jeju port passed Maengol strait and reached to approach of Byung Pung island, and then capsized and sank with a sudden inclination to the portside in the mean time of starboard the helm. In this time, the ship which has very poor stability without sufficient ballast waters and with over loading cargo listed port side caused by the centrifugal force acting to the outside of turning. A lot of cargoes not fastened moved to the port side consequently, and the ship came to beam end to capsize and sank in the end. No crews including especially captain would offer their own duties in a such extremely urgent time, as a result, enormous number of victims broke out including a lot of student. In this report, author carried out some calculation on the factors which influenced on the stability of the ship, i.e. the ship's speed, the rudder angle, the weight of cargoes and distance of movement, the surface effect of liquid in the tank. We found out that the most causes of capsize were the poor stability with heavy cargoes and insufficient amount of ballast water against the rule, and the cargoes unfastened moved one side to add the inclination as well. Above all, the owner be blamable because of the illegally operating the ship without keeping the rule.