• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.361-365
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• 2005

Since the fuel cell uses the hydrogen for its fuel. it has no emission and higher efficiency than an internal combustion engine. Also fuel cell is much quieter than engine generator and generates heat much less than engine generator. So it has advantage of Army's 'si lent watch' capability and the ability to operate undetected by the enemy. The fuel cell hybrid system combines a fuel cell power system with an ESS. The ESS (e.g., batteries or ultracapacitors) reduces the fuel cell's peak power and transient response requirements. It allows the fuel cell to operate more efficiently and recovery of vehicle energy during deceleration. The battery has high energy density, so it has the advantage regarding driving distance. However, it has a disadvantage considering dynamic characteristic because of low power density. One other hand. the ultracapacitor has higher power density, so it can handle sudden change or discharge of required power. Yet. it has lower energy density. so it will be bigger and heavier than the battery when it has the same energy. This paper proposes the power management strategy for multi-power source fuel cell hybrid system. which is applied with the merits of both battery and ultra capacitor by using both of them simultaneous.

• Korean Journal of Human Ecology
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• v.13 no.4
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• pp.617-623
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• 2004

This research studies how a rain coat (兩衣) had developed in ancient China by searching through historic records. It can be said that people in ancient China wore two kinds of rain coats: straw coat and oiled-cloth coat (油衣). Straw coat was originally used in the Spring and Autumn and Warring States period. Then, people used natural grasses to make it. As the overall production had increased, various kinds of rain coats began to appear in Tang (唐) Dynasty, and the straw coat itself became elaborate. In Song (宋) and Yuan (元) Dynasty, the straw coat was used for the army, and when it came to be Ming (明) and Qing (淸) age, wearing it was considered a symbol of hermit. The straw coat shows the early form in the history of clothing, which was mostly put on by the poor. The material for straw coat was the grass which grows up in wet land area. People in the city and in the country had worn the straw coat for a long time. As foreign cultures were introduced, however, it disappeared first in cities and later in the country. The oiled-cloth coat was another of the kind. Its major material was water-proofed silk in the Qin(泰) and Han(漢) Dynasty. Also, it was a favorite of an emperor or aristocrats. Common people put on straw coat until the time the western rain coat was introduced and accepted in Qing Dynasty.

• The Journal of Society for e-Business Studies
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• v.24 no.3
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• pp.111-128
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• 2019

In the current procurement system in Korean military, the army, navy and air force have their own distributors, military branches and warehouses. However, especially, it has been hard to have the economy of scale because most of suppliers have shipped their order from the suppliers to each of Korean military directly. Koran military considers the transportation cost as one of the management cost factors among various kinds of cost. Furthermore they have contracted with the suppliers in annual and collectively on the transportation. Hence they have been in trouble with getting efficiency of Defense budget execution because it is hard to make a decision of Defense budget with real transportation cost. Moreover Korean army, navy and air force have their own supply chain separately, so they can not cooperate flexible and quickly when they need. Therefore, in this research, we provide a benchmarking of DTCI (Defense Transportation Coordination Initiative) which has been proved that it has improved the procurement system in US implementing the integrated transportation system with 3PL and military. In addition we propose advanced integrated shipping model using Hub & Spoke system for Korean military. In order to prove its effect, we simulate our model based on the real data of the suppliers' delivery to compare with the current system when it comes to how much we can save the cost. Our research can provide evidence that the integrated procurement system in Korean military will improve Korean military procurement system.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.229-233
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• 2013

Mine detector of troops is different from other equipments. It is a base of a miner branch's combat, combat support and mission. But its notion is too obsucure and each troops' model and maker of it is so different and most of it is old type so there are a lot of malfunctions. Hence, I will define management of mine detector and figure out these days miner troops' mine detector situation. I will collect experts' opinions too. Through a discussion we could found improvement plan and develop it adequate for future operational environment. Proceeding all these courses and finally making it weaponize are the points of this writing.

• The Korean Journal of Archival Studies
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• no.21
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• pp.169-246
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• 2009

The national records management system of the Korean Government has been developed in a close relationship with changes in the administrative system. The national records management system established immediately after the establishment of the Korean Government, began to be reformed as a system with a new feature during the quick transition of the administrative system during the early 1960s. Particularly this new system holds an important meaning in that it began to cope with the mass production system of records and was established on the government level for the first time since the establishment of the government. Also this was a basic framework that defined the records management pattern of the Korean Government for the later 40 years. Therefore, this study aims to identify the origin and the meaning of the national records management system established during the early 1960s. At the time of establishing the government, the administrative system of the Korean Government was not completely free from the framework of the administrative system of the Chosen General Government. This was mainly because the Korean Government had no capability to renovate the administrative system. This was not an exception also for the national records management system. In other words, the forms and preparation methods of official document, an official document management process, and the classification and appraisal system used the records management system of the Chosen General Government without any alteration. Main factors that brought about the reform of the national records management system as well as the change in the Korean administrative system during the early 1960s, were being created in Korean society, starting from the mid 1950s. This resulted from the growth of Korean Army, public officers, and students of administrative science as being the intrinsic elites of Korean society through their respective experience of the US administration. In particular, the reform of the creation, classification, filing, transfer, and preservation system shown during the introduction of a scientific management system of the US Army in the Korean Army was a meaningful change given the historic developing process of Korean records management system history. This change had a decisive effect on the reform of the national records management system during the early 1960s. As the Korean Army, public officers, and students of administrative science, who had posted growth beginning in the mid-1950s, emerged as administrative elites during the early 1960s, the administrative system of the Korean Government brought about a change, which was different from the past in terms of its quality, and the modernization work of documentary administration pursued during the period, became extended to the reform of the national records management system. Then, the direction of reform was 'the efficient and effective control' over records based on scientific management, which was advanced through the medium of the work that accommodate the US office management system and a decimal filing system to Korean administrative circumstances. Consequently, Various official document forms, standards, and the gist of process were improved and standardized, and the appraisal system based on the function-based classification were unified on the government level by introducing a decimal filing system.

• International Journal of Computer Science & Network Security
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• v.21 no.7
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• pp.249-256
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• 2021

An issue of security and threat is urgent as well as it concerns everyone: a person, community, state, etc. Today, the question of cybersecurity has become especially relevant due to general digitalization and the spread of the cyberculture. In terms of it, the growing popularity of videogames can be observed. Their impact on society differs significantly, therefore, it needs thorough consideration. The purpose of the article is to disclose the role of videogames in cybersecurity. To achieve the stated purpose, such methods as analysis, synthesis, systematization and practical involvement of videogames have been used. As a result, three levels of possible threat of videogames has been distinguished: videogames as a possibly dangerous software, as a tool of propaganda and spread of stereotypes, as a space for the creation of virtual communities. In conclusion, it is stated that videogames can be not only a threat, but also a tool for strengthening the cybersecurity.

• Strategy21
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• s.31
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• pp.142-163
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• 2013

Ieodo is a submerged rock within a Korea's Exclusive Economic Zone(EEZ) in the East China Sea with its most shallow part about 4.6m below the sea level which has no specific rights for the EEZ delimitation. The United Nations Convention on the Law of the Sea (UNCLOS) stipulates that any coastal state has the rights to claim an EEZ that stretches up to 200 nautical miles from its shore, except where there is an overlap with a neighboring country's claims. Korea claims that Ieodo is within its EEZ as it sits on the Korean side of the equidistant line and the reef is located on the Korea section of the continental shelf. China does not recognize Korea's application of the equidistance principle and insists that Ieodo lies on its continental shelf. According to UNCLOS, Ieodo is located in international waters, rather than one country's EEZ as the two countries have failed to reach a final agreement over the delimitation of the maritime border. This study seeks to understand the evolution of the People's Liberation Army Navy(PLAN) strategy as main obstacles for the EEZ delimitation between Korea and China. PLAN's Strategy evolves from "coastal defense" to "offshore defence", since the late 1980s from a "coastal defence" strategy to an "offshore defence" strategy which would extend the perimeter of defence to between 200 nm and 400 nm from the coast. China's economic power has increased It's dependence on open trade routes for energy supplies and for its own imports and exports. China want secure Sea Lane. PLAN's "offshore defence" strategy combines the concept of active defence with the deployment of its military forces beyond its borders. China's navy try to forward base its units and to achieve an ocean going capability. China's navy expects to have a 'Blue Water' capability by 2050. China insists that coastal states do have a right under UNCLOS to regulate the activities of foreign military forces in their EEZs. China protests several times against US military forces operating within It's EEZ. The U.S. position is that EEZs should be consistent with customary international law of the sea, as reflected in UNCLOS. U.S. has a national interest in the preservation of freedom of navigation as recognized in customary international law of the sea and reflected in UNCLOS. U.S. insists that coastal states under UNCLOS do not have the right to regulate foreign military activities in their EEZs. To be consistent with its demand that the U.S. cease performing military operations in china's EEZ, China would not be able to undertake any military operations in the waters of South Korea's EEZ. As such, to preserve its own security interests, China prefers a status quo policy and used strategic ambiguity on the Ieodo issue. PLAN's strategy of coastal defence has been transformed into offensive defence, Korea's EEZ can be a serious limitation to PLAN's operational plan of activities. Considering China'a view of EEZs, China do not want make EEZ delimitation agreement between Korea and China. China argues that the overlapping areas between EEZs should be handled through negotiations and neither side can take unilateral actions before an agreement is reached. China would prefer Ieodo sea zone as a international waters, rather than one country's EEZ.

• Journal of the Korean Professional Engineers Association
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• v.12 no.1
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• pp.12-20
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• 1979

The early history of gun powder (black powder) and explosives was closely connected with the discovery of methods of preparing and purifing salpetre (potassium nitrate KNO$_3$). The Chineses apparently became acquainted with salpetre firstly on about 11th century, and they were possibly the original discoverers of salpetre for raw material of gun powder. The Egyptians called it “Chinese snow”, and it is significant that Chingis-Khan, the Mongol conqueror, took the Chinese eenginees with him in 1218 to use it for attacking the fortifications of the Persian cities. The black powder was invented by chance by Chinese alchemists during the Song dynasty (11th century) in the process of manufacturing medicine, and the powder was introduced to Europe by Mongol army. The manufacturing method of salpetre and gun powder was introduced to Korea from China in 1374, and the powder alld gunnery manufacturing project was developed by Mu Sun Choe(崔茂宣), the first Korean engineer late in Koryo dynasty. Coming in to Yi dynasty the explosive technic, extractive method of salpetre, and gunnery manufacturing process were developed greatly by Mu Sun Choe and Hai Sin Choe (崔海臣). However, confronting with the Japanes invasion at Imjin War (1597) with more powerful western style rifles which had been introduced from the Portuguese, on the contrary Korean army with the traditional guns couldn't compete with them. The Chochong(烏銃, the western rifle introduced in Japane) were much superior to the Chinese style traditional guns in the shooting power and striking efficiency. On the other hand, the Japanese battle ships armed only with the Chochong, when confronted with the Korean turtle shaped ships under the commanding of Admiral Yi Sun-Sin(李舞臣), were defeated by the Korean canons on the ships. The technical development of the modern powder industry in Korea. with the construction of four big explosive plants from 1930 to 1945, has resulted the mass-production of explosives. This study was purposed to investigate to the process with regard to the details of introduction to the explosive technology in Korea, and intended to give a help to the engineers who are engaged in study of the explosive technics by means of giving a spot light data on the early process of the designs, and making suggestion to the researchers for further study and invent a new and modern explosive.

• Journal of the Korea Society for Simulation
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• v.28 no.2
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• pp.159-167
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• 2019

In the field of defense M&S, we are actively pursuing researches that interoperable multiple war game models to simulate various combat environments at the same time. Although the 'unit DB(Database)' for operating the war game models is originated from the identical data, it has been recognized that the method of expressing the attribute of the data is different and the cross reference is impossible. As a result, it makes unnecessary time and effort in establishing the same unit DB in the organizations that operate the war game model. In this study, a method of reusing the unit DB of the training war game model to the analysis war game model with similar resolution and simulated logic was applied to the actual field. For this purpose, we defined the procedure for converting the unit DB by analyzing metadata of the 'Chang-Jo21', a combat training model for corps and division, and the 'Vision21', an analysis model for corps and division operation plan. And we introduced an algorithm that can map different metadata of two unit DBs. This study was meaningful as the first attempt to map and integrate heterogeneous metadata semantically for the reuse of unit DB between different war game models in defense M&S field. Also, it provided implications for the necessity of paradigm shift that reuse of the unit DB between two different war game models is possible and the need for standardization of the unit DB metadata in the defense M&S filed.

• Journal of the military operations research society of Korea
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• v.29 no.2
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• pp.61-80
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• 2003

A fire sequencing problem is considered. Fire sequencing problem is a kind of scheduling problem that seeks to minimize the overall time span under a result of weapon­target allocation problem. The assigned weapons should impact a target simultaneously and a weapon cannot transfer the firing against another target before all planned rounds are consumed. The computational complexity of the fire sequencing problem is strongly NP­complete even if the number of weapons is two, so it is difficult to get the optimal solution in a reasonable time by the mathematical programming approach. Therefore, a genetic algorithm is adopted as a solution method, in which the representation of the solution, crossover and mutation strategies are applied on a specific condition. Computational results using randomly generated data are presented. We compared the solutions given by CPLEX and the genetic algorithm. Above $7(weapon){\times}15(target)$ size problems, CPLEX could not solve the problem even if we take enough time to solve the problem since the required memory size increases dramatically as the number of nodes expands. On the other hand, genetic algorithm approach solves all experimental problems very quickly and gives good solution quality.