• Journal of Astronomy and Space Sciences
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• 제32권1호
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• pp.63-71
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• 2015

During the reign of King Sejong (世宗, 1418-1450) in the Joseon Dynasty, there were lots of astronomical instruments, including miniaturized ones. Those instruments utilized the technical know-how acquired through building contemporary astronomical instruments previously developed in the Song(宋), Jin(金), and Yuan(元) dynasties of China. In those days, many astronomical instruments had circles, rings, and spheres carved with a scale of 365.25, 100, and 24 parts, respectively, on their circumference. These were called the celestial-circumference degree, hundred-interval (Baekgak), and 24 direction, respectively. These scales are marked by the angular distance, not by the angle. Therefore, these circles, rings, and spheres had to be optimized in size to accomodate proper scales. Assuming that the scale system is composed of integer multiples of unit length, we studied the sizes of circles by referring to old articles and investigating existing artifacts. We discovered that the star chart of Cheonsang yeolcha bunyajido was drawn with a royal standard ruler (周尺) based on the unit length of 207 mm. Interestingly, its circumference was marked by the unit scale of 3 puns per 1 du (or degree) like Honsang (a celestial globe). We also found that Hyeonju ilgu (a equatorial sundial) has a Baekgak disk on a scale of 1 pun per 1 gak (that is an interval of time similar to a quarter). This study contributes to the analysis of specifications of numerous circular elements from old Korean astronomical instruments.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2000년도 춘계학술발표논문집
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• pp.118-125
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• 2000

Gloss uniformity on unprinted coated papers is oftenly called as 'Surface Feeling' in market and roles as a very important criteria when a customer choose a paper. However, there is few researches on this quality so far and even there isn't much knowledge on the characteristics of gloss variation, ie what it is, where it comes from etc. Therefore, there should be a pre-research on its characteristics, factors, measuring method or tools prior to the following development activities. In this paper, we obtained about a dozen of papers including foreign products and measured not only basic properties of them, but also various characteristics related to ununiformity. Our experiments went further to printing, but that area is excluded in this paper. Also, we investigated several instruments for measuring gloss variation by an objective way all over the world and tested with our own samples so that we tried to find out which one is best-correlated with visual appreciation and suggest its results as possible. We found out several things from these experiments including what is difference between good and bad gloss uniformity, the factors of gloss variation, and the results of measurement for gloss variation with instruments.

• 펄프종이기술
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• 제44권4호
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• pp.43-50
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• 2012

The crystallinity index is an important characteristic of cellulose. The crystallinity value is different depending on the adopted instrument. In this study, we determined a crystallinity index of cotton and wood celluloses using wide-angle X-ray scattering (WAXS), powder X-ray diffractometer (PXRD), and cross polarization/magic angle spinning solid-state $^{13}C$ nuclear magnetic resonance spectroscopy (CP/MAS solid-state $^{13}C$ NMR). The specimen was prepared in forms of powder, sheet and pallet. With the comparison of the obtained crystallinity indices of the cellulose, the effects of the analysis instrument, the sample preparation and analysis method were investigated. Among three instruments, the crystallinity indices by PXRD and NMR had a good relationship and reproducibility, and WAXS gave the crystallinity index with poor reproducibility. In the case of analysis methods of crystallinity indices, the Segal method showed higher value than that of the Ruland-Vonk method. We expect that this study would be applicable to evaluate the crystallinity index of various cellulose materials with accuracy and reproducibility.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.102-105
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• 2005

Between 1920 and 1996, a total of 39 Conventions, 29 Recommendations and one Protocol were adopted by the International Labour conference. But Many ILO Instruments were outdated, deficient and not reflective of modern practice, many contained technical detail which discouraged ratification and were thus ineffective. However, many issues which had become relevant were not covered by existing instruments. Therefore, the Governing Body of ILO, at its 262nd Session(March-April 1995), decided to set up a Working Party on Policy regarding the Revision of Standards. It was decided that the Working Party would examine the need for revision of all maritime Conventions and Recommendations adopted before 1985 with a view to rejuvenating and strengthening the standard-setting system. The Working Party initiated its examination of maritime instruments during 273rd Session(November 1998) of the Governing Body. The review made by the Working Party has concluded that of the maritime Conventions examined, seven of them are obsolete and should be revised, 13 should be denounced and six were considered either up to date or were identified for promotion, most of which were approved by the Governing Body. The consolidated maritime labour convention will be adopted in February 2006.

• Journal of Astronomy and Space Sciences
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• 제32권3호
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• pp.167-180
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• 2015

Herein, we discuss the in situ measurement of the electron temperature in the ionosphere/plasmasphere by means of DC Langmuir probes. Major instruments which have been reported are a conventional DC Langmuir probe, whose probe voltage is swept; a pulsed probe, which uses pulsed bias voltage; a rectification probe, which uses sinusoidal signal; and a resonance cone probe, which uses radio wave propagation. The content reviews past observations made with the instruments above. We also discuss technical factors that should be taken into account for reliable measurement, such as problems related to the contamination of electrodes and the satellite surface. Finally, we discuss research topics to be studied in the near future.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1995년도 VTS and IBS 95 The Korean Institute of Navigation 1995년도
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• pp.125-152
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• 1995

An Integrated Bridge System (IBS) is not an officially defined term, but a concept of which integrates on a consol at bridge the primary functions of stand-alone navigational aids and communication instruments or of stand-alone units which are integrated i.e. ARPA ECDIS It aims to enable officers on navigational watch to perform their duty without impairing proper lookout. IBS has been taking shape through a rapid development of navigation and communication systems in relation with bridge configuration bridge work station and one man bridge operation system. IBS related matters have been considered for years and is on the agenda of the International Maritime Organization(IMO) for its technical details and safety aspect of possible one-man watchkeeping at night. However IMO has made it clear that human element should be the key factor in considering IBS and single watchkeeping issue. In the development of IBS ergonomic element and human psychological aspect have been more emphasized than technical requirements. This paper refers to documents presented to the IMO and its progress made in various IMO technical meetings on the development of IBS which is perceived as an effective aid to proper bridge lookout and those standards adopted by classification societies on the composition of workstation at bridge in order to identify the international trend on regulating required equipment function of workstation of IBS the regulatory review process and technical recommendations related thereto.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국제학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.928-933
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• 1988

Control technology has been making remarkable progress in electrical control (E), instrumentation & control (I) and computer control (C) field respectively. In order to rationalize system engineering and simplify system configuration and operation work, so called, EIC are now to be integrated into one system. FUJI has developed it's own E, I&C integrated system, to meet above mentioned market requirements of variety. This paper describes basic concept of FUJI's Integrated Man-Machine Interface, hereinafter called SINGLE CONSOLE, from some view points of E, I, C integration technology.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.282-285
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• 2004

Every year, the last products from most important builders of high bandwidth digitizers are tested in our laboratory which is specialized in the design and the characterization of fast links used in large laser facility. The purpose of this article is to describe the series of tests conducted during the characterization of such digitizers. More particularly, it takes an interest in the metrology of instruments with more than 5 GHz of bandwidth. It presents the different methods used and the kind of conclusion that we can give after such study. Such metrology campaign which usually takes one month of work, allows us to observe the smallest details and characteristics that usually builders don't give in their tables specifications. After the campaign, a copy of our technical report is written and sends to the builder. This report can be used by the technical team to ameliorate the points we noted.

• Journal of Korean Neurosurgical Society
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• 제63권1호
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• pp.4-13
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• 2020

For surgical minimalism to reduce iatrogenic traumatization, a supraorbital keyhole approach has already been successfully applied to treat many unruptured anterior circulation aneurysms. However, using this minimal approach also raises several technical concerns due to the small cranial opening and cosmetic impact of a facial incision. Yet, such technical limitations can be overcome by using favorable surgical indications, slender surgical instruments, and optimized surgical techniques, while excellent cosmetic outcomes can be achieved using a short skin incision located <1 cm from the supraorbital margin, reconstruction of any bone defects around the bone flap, and meticulous wound closure. Thus, given such reassuring surgical results, in terms of the clipping status, neurological effects, and cosmetic outcomes, any concerns can be transitioned into confidence.

• Journal of Gastric Cancer
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• 제12권3호
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• pp.133-139
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• 2012

Laparoscopic gastrectomy has become widely used as a minimally invasive technique for the treatment of gastric cancer. When it was first introduced, most surgeons preferred a laparoscopic-assisted approach with a minilaparotomy rather than a totally laparoscopic procedure because of the technical challenges of achieving an intracorporeal anastomosis. Recently, with improved skills and instruments, several surgeons have reported the safety and feasibility of a totally laparoscopic gastrectomy with intracorporeal anastomosis. This review describes the recent technical advances in intracorporeal anastomoses using circular and linear staplers that allow for totally laparoscopic distal, total, and proximal gastrectomies. Data that demonstrate advantages in early surgical outcomes of a total laparoscopic method compared to laparoscopic-assisted operations are also discussed.