• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.4
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• pp.491-498
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• 2018

The cost evaluation for voyage route planning in an ice-covered sea is one of the major topics among ship owners. Information of the ice properties, such as ice type, concentration of ice, ice thickness, strength of ice, and speed-power relation under ice conditions are important for determining the optimal route in ice and low operational cost perspective. To determine achievable speed at any designated pack ice condition, a model test of resistance, self-propulsion, and overload test in ice and ice-free water were carried out in a KRISO ice tank and towing tank. The available net thrust for ice and an estimation of the ice resistance under any pack ice condition were also performed by I-RES. The in-house code called 'I-RES', which is an ice resistance estimation tool that applies an empirical formula, was modified for the pack ice module in this study. Careful observations of underwater videos of the ice model test made it possible to understand the physical phenomena of underneath of the hull bottom surface and determine the coverage of buoyancy. The clearing resistance of ice can be calculated by subtracting the buoyance and open water resistance form the pre-sawn ice resistance. The model test results in pack ice were compared with the calculation results to obtain a correlation factor among the pack ice resistance, ice concentration, and ship speed. The resulting correlation factors were applied to the calculation results to determine the pack ice resistance under any pack ice condition. The pack ice resistance under the arbitrary pack ice condition could be estimated because software I-RES could control all the ice properties. The available net thrust in ice, which is the over thrust that overcomes the pack ice resistance, will change the speed of a ship according to the bollard pull test results and thruster characteristics (engine & propulsion combination). The attainable speed at a certain ice concentration of pack ice was determined using the interpolation method. This paper reports a procedure to determine the attainable speed in pack ice and the sample calculation using the Araon vessel was performed to confirm the entire process. A more detailed description of the determination of the attainable speed is described. The attainable speed in 1.0 m, 90% pack ice and 540 kPa strength was 13.3 knots.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.3
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• pp.213-232
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• 2009

This document was prepared to review and summarize the analytical methods for airborne and bulk asbestos. Basic principles, shortcomings and advantages for asbestos analytical instruments using phase contrast microscopy(PCM), polarized light microscopy(PLM), X-ray diffractometer (XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM) were reviewed. Both PCM and PLM are principal instrument for airborne and bulk asbestos analysis, respectively. If needed, analytical electron microscopy is employed to confirm asbestos identification. PCM is used originally for workplace airborne asbestos fiber and its application has been expanded to measure airborne fiber. Shortcoming of PCM is that it cannot differentiate true asbestos from non asbestos fiber form and its low resolution limit ($0.2{\sim}0.25{\mu}m$). The measurement of airborne asbestos fiber can be performed by EPA's Asbestos Hazard Emergency Response Act (AHERA) method, World Health Organization (WHO) method, International Standard Organization (ISO) 10312 method, Japan's Environmental Asbestos Monitoring method, and Standard method of Indoor Air Quality of Korea. The measurement of airborne asbestos fiber in workplace can be performed by National Institute for Occupational Safety and Health (NIOSH) 7400 method, NIOSH 7402 method, Occupational Safety and Health Administration (OSHA) ID-160 method, UK's Health and Safety Executive(HSE) Methods for the determination of hazardous substances (MDHS) 39/4 method and Korea Occupational Safety and Health Agency (KOSHA) CODE-A-1-2004 method of Korea. To analyze the bulk asbestos, stereo microscope (SM) and PLM is required by EPA -600/R-93/116 method. Most bulk asbestos can be identified by SM and PLM but one limitation of PLM is that it can not see very thin fiber (i.e., < $0.25{\mu}m$). Bulk asbestos analytical methods, including EPA-600/M4-82-020, EPA-600/R-93/116, OSHA ID-191, Laboratory approval program of New York were reviewed. Also, analytical methods for asbestos in soil, dust, water were briefly discussed. Analytical electron microscope, a transmission electron microscope equipped with selected area electron diffraction (SAED) and energy dispersive X-ray analyser(EDXA), has been known to be better to identify asbestiform than scanning electron microscope(SEM). Though there is no standard SEM procedures, SEM is known to be more suitable to analyze long, thin fiber and more cost-effective. Field emission scanning electron microscope (FE-SEM) imaging protocol was developed to identify asbestos fiber. Although many asbestos analytical methods are available, there is no method that can be applied to all type of samples. In order to detect asbestos with confidence, all advantages and disadvantages of each instrument and method for given sample should be considered.

• Journal of Korean Society of Steel Construction
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• v.29 no.5
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• pp.389-400
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• 2017

Based on U-shaped composite beam, the new form of AU-composite beam were developed to create economical and efficient components reducing the cost and shortening the length of construction work. Because the U-shaped sections are open and needs to be fixed by topping concrete securely. Therefore, it is required to maintain the U-shaped sections in a structure and to work in the safe condition through construction. It also requires accessories that resist the horizontal shear force for synthesis between the top and bottom of the U-shaped section. To reinforce these shortcomings, a shear connector has been developed with various purposes of steel plate anchors. In this study, the steel plate anchors were directly tested and the shear force was evaluated by the horizontal shear force. The experiment was divided into two types, depending on the applicable deck plates. As a result of the experiment, the continuous type specimens showed greater resistance in both strength and displacement than the ones of stud anchor specimen. In discontinuous type case, due to shear simulations and simple element analysis, the less increase the ratio of width to height and the more shear strength decreased. Thus, the shear strength equation of the stud anchor was modified to suggest the new shear strength based on the testing results.

• Journal of Science and Technology Studies
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• v.18 no.2
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• pp.7-41
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• 2018

The projects of citizen science which is originated from citizen data collecting action driven by governmental institutes and science associations have been implemented with different form of collaboration with scientists. The themes of citizen science has extended from the ecology to astronomy, distributed computing, and particle physics. Citizen science could contribute to the advancement of science through cost-effective science research based on citizen volunteer data collecting. In addition, citizen science enhance the public understanding of science by increasing knowledge of citizen participants. The community-led citizen science projects could raise public awareness of environmental problems and promote the participation in environmental problem-solving. Citizen science projects based on local tacit knowledge can be of benefit to the local environmental policy decision making and implementation of policy. These social values of citizen science make many countries develop promoting policies of citizen science. The korean government also has introduced some citizen science projects. However there are some obstacles, such as low participation of citizen and scientists in projects which the government has to overcome in order to promote citizen science. It is important that scientists could recognize values of citizen science through the successful government driven citizen science projects and the evaluation tool of scientific career could be modified in order to promote scientist's participation. The project management should be well planned to intensify citizen participation. The government should prepare open data policy which could support a data reliability of the community-led monitoring projects. It is also desirable that a citizen science network could be made with the purpose of sharing best practices of citizen science.

• The Journal of Art Theory & Practice
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• no.14
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• pp.87-124
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• 2012

This paper focuses on the social implication of new media art, which has evolved with the advance of technology. To understand the notion of human-computer interactivity in media art, it examines the meaning of "cybernetics" theory invented by Norbert Wiener just after WWII, who provided "control and communication" as central components of his theory of messages. It goes on to investigate the application of cybernetics theory onto art since the 1960s, to which Roy Ascott made a significant contribution by developing telematic art, utilizing the network of telecommunication. This paper underlines the significance of the relationship between human and machine, art and technology in transforming the work of art as a site of communication and experience. The interactivity in new media art transforms the viewer into the user of the work, who is now provided free will to make decisions on his or her action with the work. The artist is no longer a godlike figure who determines the meaning of the work, yet becomes another user of his or her own work, with which to interact. This paper believes that the interaction between man and machine, art and technology can lead to various ways of interaction between humans, thereby restoring a sense of community while liberating humans from conventional limitations on their creativity. This paper considers the development of new media art more than a mere invention of new aesthetic styles employing advanced technology. Rather, new media art provides a critical shift in subverting the modernist autonomy that advocates the medium specificity. New media art envisions a new art, which would embrace impurity into art, allowing the coexistence of autonomy and heteronomy, embracing a technological other, thereby expanding human relations. By enabling the birth of the user in experiencing the work, interactive new media art produces an open arena, in which the user can create the work while communicating with the work and other users. The user now has freedom to visit the work, to take a journey on his or her own, and to make decisions on what to choose and what to do with the work. This paper contends that there is a significant parallel between new media artists' interest in creating new experiences of the art and Jacques Ranci$\grave{e}$re's concept of the aesthetic regime of art. In his argument for eliminating hierarchy in art and for embracing impurity, Ranci$\grave{e}$re provides a vision for art, which is related to life and ultimately reshapes life. Ranci$\grave{e}$re's critique of both formalist modernism and Jean-Francois Lyotard's postmodern view underlines the social implication of new media art practices, which seek to form "the common of a community."

• Journal of Korea Water Resources Association
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• v.41 no.8
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• pp.761-772
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• 2008

The object of this study is to develop the model that solves the numerically difficult problems in hydraulic engineering and to demonstrate the applicability of this model by means of various test examples, such as, verification in the gradually varied unsteady condition, three steady flow problems with the change of bottom slope with exact solution, and frictional bed with analytical solution. The governing equation of this model is the integral form of the Saint-Venant equation satisfying the conservation laws, and finite volume method with the Riemann solver is used. The evaluation of the mass and momentum flux with the HLL Riemann approximate solver is executed. MUSCL-Hancock scheme is used to achieve the second order accuracy in space and time. This study introduce the new and simple technique to discretize the source terms of gravity and hydrostatic pressure force due to longitudinal width variation for the balance of quantity between nonlinear flux and source terms. The results show that the developed model's implementation is accurate, robust and highly stable in various flow conditions with source terms, and this model is reliable for one-dimensional applications in hydraulic engineering.

• Childhood Kidney Diseases
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• v.1 no.2
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• pp.189-194
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• 1997

Oligomeganephronia is a rare congenital form of bilateral renal hypoplasia histologically characterized by reduction in number and hypertrophy of nephrons. Clinically, this condition is presented in early infancy with vomiting, polyuria, polydipsia and dehydration. The problems are readily corrected, but slowly progressive renal failure follows accompanied by failure to thrive, short stature, and renal osteodystrophy. We experienced three cases of oligomeganephronia. Case 1. : A 3 2/12 years old female child was incidentally diagnosed as renal failure at age of 2 months when she was hospitalized due to pneumonia. She had open renal biopsy and was diagnosed as bilateral dysplastic kidney. On OPD follow-up, she progressed to end-stage renal failure (BUN/Cr 114/4.6 mg/dl) and had renal transplantation. The specimen was shrunk remarkably and light microscopy showed oligomeganephronia. Case 2. : A 14 8/12 years old female child with proteinuria was detected in an annual urine screening program for school children, she was diagnosed as renal failure (BUN/Cr 33.9/4.1 mg/dl), and had $5{\times}4{\times}3\;cm$ sized mass on abdominal CT scan. She had renal biopsy, and the specimen showed oligomeganephronia. She had hemodialysis for six months, and renal transplantation along with bilateral nephrectomy was performed. Case 3. : A 14 8/12 years old male child was diagnosed having chronic nephritis and chronic renal failure at 3 years old, progressed to end-stage renal failure (BUN/Cr 87/9.6 mg/dl) on OPD follow-up, and had a rephrectomy and renal transplantation. The biopsy specimen showed oligomeganephronic hypoplasia, secondary focal segmental glomerolosclerosis, and chronic interstitial nephritis. We report 3 cases of oligomeganephronia that progressed to end-stage renal failure and had successful renal transplantation with a brief review of related literatures.

• Review of Korean Society for Internet Information
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• v.14 no.3
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• pp.78-85
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• 2013

The revelations made possible by Edward Snowden, a contractor of the US intelligence service NSA, are a sobering reminder that the Internet is not an 'anonymous' means of communication. In fact, the Internet has never been conceived with anonymity in mind. If anything, the Internet and networking technologies provide far more detailed and traceable information about where, when, with whom we communicate. The content of the communication can also be made available to third parties who obtain encryption keys or have the means of exploiting vulnerabilities (either by design or by oversight) of encryption software. Irrebuttable evidence has emerged that the US and the UK intelligence services have had an indiscriminate access to the meta-data of communications and, in some cases, the content of the communications in the name of security and protection of the public. The conventional means of judicial scrutiny of such an access turned out to be ineffectual. The most alarming attitude of the public and some politicians is "If you have nothing to hide, you need not be concerned." Where individuals have nothing to hide, intelligence services have no business in the first place to have a peek. If the public espouses the groundless assumption that State organs are benevolent "( they will have a look only to find out whether there are probable grounds to form a reasonable suspicion"), then the achievements of several hundred years of struggle to have the constitutional guarantees against invasion into privacy and liberty will quickly evaporate. This is an opportune moment to review some of the basic points about the protection of privacy and freedom of individuals. First, if one should hold a view that security can override liberty, one is most likely to lose both liberty and security. Civilized societies have developed the rule of law as the least damaging and most practicable arrangement to strike a balance between security and liberty. Whether we wish to give up the rule of law in the name of security requires a thorough scrutiny and an informed decision of the body politic. It is not a decision which can secretly be made in a closed chamber. Second, protection of privacy has always depended on human being's compliance with the rules rather than technical guarantees or robustness of technical means. It is easy to tear apart an envelope and have a look inside. It was, and still is, the normative prohibition (and our compliance) which provided us with protection of privacy. The same applies to electronic communications. With sufficient resources, surreptitiously undermining technical means of protecting privacy (such as encryption) is certainly 'possible'. But that does not mean that it is permissible. Third, although the Internet is clearly not an 'anonymous' means of communication, many users have a 'false sense of anonymity' which make them more vulnerable to prying eyes. More effort should be made to educate the general public about the technical nature of the Internet and encourage them to adopt user behaviour which is mindful of the possibilities of unwanted surveillance. Fourth, the US and the UK intelligence services have demonstrated that an international cooperation is possible and worked well in running the mechanism of massive surveillance and infiltration into data which travels globally. If that is possible, it should equally be possible to put in place a global mechanism of judicial scrutiny over a global attempt at surveillance.

• Journal of the Korean Society for Library and Information Science
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• v.25
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• pp.151-183
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• 1993

As many Korean libraries has begun to be automated and become a part of the worldwide, open library system, they need a new management. Therefore, the purpose of this paper is to explore the library management in automated libraries and to establish a theory of the library management in information society, The automated libraries could be well explained by the systems theory and the environment of the libraries could be well explained by the contingency theory, The following hypothesis were set to direct this research. 1. As the libraries are automated and become a part of one big, worldwide library system, the libraries interact closely with the environment so that the library and the environment become one. 2. As the libraries are automated and become a part of one big, worldwide library system, the librarians need to work in the environment for the library networks, standardization of cataloging, or government information policy making. 3. As the libraries are automated and become a part of one big, worldwide library system, the librarians only manage the library, The various other library staffs take over the traditional library services directly related to books. The data were gathered from the research done previously, Also the date were collected from the American and Japanese libraries. The findings were as follows: The environment of the library integrated all types of the library services such as school library, university library, etc. And it also integrated all the services of the media centers and the press centers, etc. to library services. And the new library services began in the environment. Librarians worked for these new services. In the library, the librarians distingushed the library system from the environment by planning : mission, goal, objectives, policy, procedures and rules. Library organization became temporary such as forming task forces or matrix or free form. The environment controlled the library. Staffs were controlled by plans or computers. And the professional librarians were controlled by their ability to solve problems raised outside the libraries. Library leaders brought in the technology to the library from its environment. The librarians led the formal and informal organizations so that the staffs cooperated well in their work. And librarians tought the library procedures to the partime workers or the temporary staffs. Participative management and management by objectives were the means of motivating staffs. Budget was based on the ever changing environment. The zero based budget method was applied. Therfore, in the information society, the professional librarians become the able managers in the library and global librarians in the environment.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.3
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• pp.224-235
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• 2014

Changes in the interactions among incident ocean water waves, coastal debris (marine debris), and the back vegetation zone line on a natural sandy beach on the island of Jinu-do in the Nakdong river estuary were investigated. The study involved a cross-sectional field survey of the beach, numerical modeling of incident ocean water waves, field observations of the distribution of coastal debris, and vegetation zone line tracking using GPS. The conclusions of this study can be summarized as follows: (1) The ground level of the swash zone (sandy beach) on Jinu-do is rising, and the vegetation zone line, which is the boundary of the coastal sand dunes, shows a tendency to move forward toward the open sea. The vegetation zone line is developing particularly strongly in the offshore direction in areas where the ground level is elevated by more than 1.5 m. (2) The spatial distributions of incident waves differed due to variations in the water depth at the front of the beach, and the wave run-up in the swash zone also displayed complex spatial variations. With a large wave run-up, coastal debris may reach the vegetation zone line, but if the run-up is smaller, coastal debris is more likely to deposit in the form of an independent island on the beach. The deposited coastal debris can then become a factor determining which vegetation zone line advances or retreats. Finally, based on the results of this investigation, a schematic concept of the mechanisms of interaction between the coastal debris and the coastal vegetation zone line due to wave action was derived.