• Journal of Advanced Marine Engineering and Technology
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• v.23 no.3
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• pp.346-351
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• 1999

This paper is a research for removing the hunting which came about during the parallel running of the alternators which four-pole six-phase have the converter with twelve diodes to rectify all the waves. Druing the parallel running the hunting came about under the period of 0.2-0.3{sec} not when it's load was the resistance but the capacity at the rpm band 1575[rpm] 1690[rpm] This hunting in our judgement was not come about from the general hunting causes which have been already known to but the special example. And so we checked that the hunting came about or not as per the changes of the rpm exciting current load current and converter and converter output voltage and the following facts were revealed. -The hunting occured during the constant voltage charging where r. p. m band is from 1575[rpm] to 1690[rpm] - The hunting did not came about during the constant power charging in which there was the large difference between the converter output voltage and the battery voltage. -The hunting did not came about in the low rpm band. We could see from the above facts that the existence of the hunting inducing point at the con-stant voltage charging band was the direct cause of the hunting. After trying every possible means to remove the hunting inducing point we could know that the modification of the synchronous generator is suitable for he purpos in view of the small engine room.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.285-286
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• 2008

• Korean Journal of Heritage: History & Science
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• v.46 no.2
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• pp.166-185
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• 2013

After analyzing the location, arrangement, inner structure, and form of the hunting pit in the Bronze Age, this paper sets up three types and talks about types of hunting pits. After analyzing the types of the hunting pit, three types of hunting pits are derived: mountain district - large group's arrangement - long oval - I II type(A), mountain district - arrangement in a line - oval - I type(B), flat area - arrangement in a line - oval - I III type(C). Literature, the ways in hunting pits, the purpose of the installations, and the characters are studied and compared with those of the anthropological cases. Even though hunting pits of types A and B are constructed to hide and get protein and bone of animals for breeding, there are differences in the ways in hunting and characters. Type of A seems to be constructed only for occupation that is the standardized hunting method on a small works. However, type B is the chasing method to hunt as a group and it has various purposes including main occupation. For example, it is for improving the war skills by practicing the hunting strategies and cooperating with the people. In addition, it is for getting a sacrifice for god. The type C hunting pit is estimated that it plays a role to protect themselves from invasion. It's inferred that there are many purposes for military defense and protection of people or animals within the village. It is the reason why the construction is spread in hunting pit including various purposes in the Bronze age that originates in social and economical specialization like the increase in agricultural productivity and appearance of a chief.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.3
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• pp.352-359
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• 1999

This paper is a research for removing the alternators hunting which came about during the par-allel running. The four-pole six-phase alternator is equipped with the converter made out of twelve diodes to rectify all the waves. The hunting came about during the battery charging due to the hunting inducing point existed in r. p. m band 1575[rpm-1690[rpm] To remove the hunting inducing point We modified the four-pole six-phase alternator into the four-pole twevel-phase and increased the short-circuit ratio by decreasing the field coil pitch and increasing the field coil turns. But this method has two defects the first the alternator structure becomes complicating and the second the second the alternator equipped with the converter used in general purpose lately such as the car alternator can not be run in parallel wlthout modifying. To remove the defects the equalizing line was connected between the same phase of the alterna-tor to flow the synchronizing current which syncronize the phases of generator electromotive forces by which the alternator can be run in parallel without reference to the hunting inducing point and without modifying.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.150-157
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• 2005

Generally, the flow hunting is observed in almost all of the orifice meters but the intensity of the flow hunting is different at each metering system. So, we were getting some Questions as follows; why such a difference occurs and whether it influence to metering error rate or not. To investigate the flow hunting characteristics, we are trying to examine the flow characteristics around the orifice meter when the transient flow or pressure is generated at after the PCV(Pressure Control Valve) by 3D CFD method. And we have compared numerical results with experimental results at M - PCV station in order to clarify the relations with both the metering-pipeline diameter and flow rate. Finally, we can show some major factors influencing to the flow hunting and propose some correcting scheme of the flow hunting equation.

• Structural Engineering and Mechanics
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• v.52 no.2
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• pp.351-368
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• 2014

This study presents a hunting search based optimum design algorithm for engineering optimization problems. Hunting search algorithm is an optimum design method inspired by group hunting of animals such as wolves, lions, and dolphins. Each of these hunters employs hunting in a different way. However, they are common in that all of them search for a prey in a group. Hunters encircle the prey and the ring of siege is tightened gradually until it is caught. Hunting search algorithm is employed for the automation of optimum design process, during which the design variables are selected for the minimum objective function value controlled by the design restrictions. Three different examples, namely welded beam, cellular beam and moment resisting steel frame are selected as numerical design problems and solved for the optimum solution. Each example differs in the following ways: Unlike welded beam design problem having continuous design variables, steel frame and cellular beam design problems include discrete design variables. Moreover, while the cellular beam is designed under the provisions of BS 5960, LRFD-AISC (Load and Resistant Factor Design-American Institute of Steel Construction) is considered for the formulation of moment resisting steel frame. Levy Flights is adapted to the simple hunting search algorithm for better search. For comparison, same design examples are also solved by using some other well-known search methods in the literature. Results reveal that hunting search shows good performance in finding optimum solutions for each design problem.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.4
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• pp.51-58
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• 2008

This paper presents a new design of the precision stage for the reticle in lithography process and a low hunting control method for the stage. The stage has three axes for X, Y, ${\theta}_z$ those actuated by three voice coil motors individually. The designed reticle stage system has three gap sensors and voice coil motors, and supported by four air bearings and the forward/inverse kinematics of the stage were solved to get an accurate reference position. When a stage is in regulating control mode, there always exist small fluctuations(stage hunting) in the stage movement. Because the low stage hunting characteristic is very important in recent lithography and nano-level applications, a special regulating controller for ultra low hunting is proposed in this paper. Also this research proposed the 2-step transmission system for preventing the noise infection from environmental devices. The experimental results showed the proposed regulating control system reduced hunting noise as 35nm(rms) when a conventional PID generates 77nm(rms) in the same mechanical system. Besides the reticle stage has 100nm linear accuracy and $1{\mu}rad$ rotation accuracy at the control frequency of 8kHz.

• The Korean Journal of Quaternary Research
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• v.31 no.2
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• pp.23-30
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• 2017

There are many uncertainty to understand the ways in which Paleolithic men hunted animals. But in the meantime, We can identify a part of the hunting activities of the old people through artworks left by the paleolithic people at that time. First is the size of the hunt. In the case of painted artwork, the size of the herd does not exceed 10 people. Therefore, a small group of about 10 people would go out for a hunt, and they could see that the size of the herd varied according to the hunting target. In other words, to catch large and wild beasts like bison, you can see that it consists of nine or seven groups. In order to catch the horse, the same large animal, we can see that six people joined together. On the other hand, a group of two or three people hunting a relatively small, mild animal such as a deer would have been enough. Therefore, the size of the hunting herd was less than 10 people, and the size of the hunting herd seemed to be slightly different for each animal. Second, it is confirmed that these groups have a well-divided role. Because all nine of them were hunted out, they were divided into four small groups, which is likely to imply that the role of each group was different. Third, we can see that most of the weapons of the hunting herds were spears. The production and use of stone tools have been progressively developed, making a small stoner, a small stoneware, and connecting it to the spears, making it more efficient to hunt. This kind of composite wool connecting stone tools and wood would have been the most efficient means of hunting.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.4
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• pp.15-23
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• 2021

In most hacking attacks, hackers intrudes inside for a long period of time and attempts to communicate with the outside using a circumvent connection to achieve purpose. research in response to advanced and intelligent cyber threats has been mainly conducted with signature-based detection and blocking methods, but recently it has been extended to threat hunting methods. attacks from organized hacking groups are advanced persistent attacks over a long period of time, and bypass remote attacks account for the majority. however, even in the intrusion detection system using intelligent recognition technology, it only shows detection performance of the existing intrusion status. therefore, countermeasures against targeted bypass rwjqthrwkemote attacks still have limitations with existing detection methods and threat hunting methods. in this paper, to overcome theses limitations, we propose a model that can detect the targeted circumvent connection remote attack threat of an organized hacking group. this model designed a threat hunting process model that applied the method of verifying the origin IP of the remote circumvent connection, and verified the effectiveness by implementing the proposed method in actual defense information system environment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.12
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• pp.1243-1249
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• 2014

The naval mine is the explosives that are installed in the water in order to attack surface ships or submarines. So mine warfare is a very important component of naval operations. In this paper, first, understanding of the general concept about mine warfare. Second, introduce the mine hunting progress and mine sweeping progress. And then, suggest the system design method of mine counter measure warfare using several functions. The functions are mine area detection algorithm for side scan sonar image using Adaboost algorithm, and calculation to mine hunting progress rate and mine sweeping progress rate. And techniques that lead the mine disposal vehicle(MDV) to mine.