• Journal of Pharmaceutical Investigation
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• v.13 no.1
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• pp.1-9
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• 1983

The effect of humidity on crystallization and polymorphic transformation of hydrous aluminum oxide under various humidity at $37^{\circ}$ was examined by means of X-ray diffraction, scanning electron micrograph, IR spectra and DTA. The humidity was an important factor influencing crystallization of hydrous aluminum oxide. The growth or crystal was strongly accelerated by humidity. The aging process is assumed that it is composed of two seperate steps, an increase of the diffraction around $36{\sim}42^{\circ}$, and an appearance and its development of the peak at $18{\sim}20^{\circ}$ of $2{\theta}$ value. The former is considered to be nucleation and the latter correspond to the growth period on crystallization. The crystalline form of aging products was various depending on the degree of humidity, directly it leads to the eventual formation of bayerite in more than 72%, $b{\"{o}}hmite$ in 50% and resembled to Nordstandite in 0% relative humidity, respectively but once formed, it was mostly stable in each surroundings and does not transform to the other more stable form in solid state even after aging for five years. The mechanism responsible for aging is further polymerization process of six-membered rings by deprotonation-dehydration reaction in which positively charged polynuclear hydroxy aluminum complexes formed in the presence of moisture are joined at their edges by double hydroxide bridges.

• Journal of Pharmaceutical Investigation
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• v.41 no.2
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• pp.75-82
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• 2011

LB71350 is an HIV protease inhibitor with poor aqueous solubility and extensive first pass effect. The purpose of the present study was to test the feasibility of solid dosage form of LB71350 with improved bioavailability utilizing solid dispersion. Three different compositions with varying ratio of (LB71350: Gelucire 44/14: Tween 20) were studied. Capsule filling of these solid dispersion compositions was tested using a semi-automatic capsule filling system. Oral bioavailability in dog was tested. Chemical and physical stability at 4, 25 and $40^{\circ}C$ was monitored by HPLC assay, dissolution test, powder XRD and microscopy. The capsule filling system yielded uniform products of drug loading up to 10%. Oral bioavailability in dog was improved compared to the aqueous suspension of crystalline LB71350. Capsules were chemically stable for up to 6 months at $40^{\circ}C$. However, there were temperature and composition dependent physical changes. Decrease in dissolution rates after storage at $40^{\circ}C$ was due to the polymorphic change. In conclusion, manufacturing process, bioavailability, and physico-chemical stability have been considered to propose a solid dispersion capsule formulation for the HIV protease inhibitor with poor physico-chemical properties. A new less soluble crystalline form identified during the physical stability test warrants further study.

• Journal of the Korean Magnetic Resonance Society
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• v.14 no.2
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• pp.117-126
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• 2010

Hsp33 is a molecular chaperone achieving a holdase activity upon response to a dual stress by heat and oxidation. Despite several crystal structures available, the activation process is not clearly understood, because the structure inactive Hsp33 as its reduced, zinc-bound, monomeric form has not been solved yet. Thus, we initiated structural investigation of the reduced Hsp33 monomer by NMR. In this study, to overcome the high molecular weight (33 kDa), the protein was triply isotope-[$^{13}C$, $^{15}N$, $^2H$]-labeled and its inactive, monomeric state was ensured. 2D-[$^1H$, $^{15}N$]-TROSY and a series of triple resonance spectra could be successfully obtained on a high-field (900 MHz) NMR machine with a cryoprobe. However, under all of the different conditions tested, the number of resonances observed was significantly less than that expected from the amino acid sequence. Thus, a possible contribution of dynamic conformational exchange leading to a line broadening is suggested that might be important for activation process of Hsp33.

• Korean Journal of Plant Taxonomy
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• v.50 no.3
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• pp.368-375
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• 2020

This study presents a survey of the bryophytes of evergreen broad-leaved forest near Baekyaki Oreum in Gujwa-Seongsan Gotjawal in the eastern part of Jejudo Island, Korea. A total of 53 taxa belonging to Bryophyta (11 families 26 genera 39 species) and Marchantiophyta (9 families, 9 genera 14 species) were determined, and the liverwort index was found to be 26.4%. The predominant life-form was the mat type. The rates of bryophytes dominating at mesic to hygric sites were higher than those of bryophytes, which were mainly observed in xeric habitats. These values indicate that the forest areas in this study area have a high density level. Upon an investigation of the substrates, bryophytes on rocks were most diverse. It was also found that volcanic rock masses of various sizes lay scattered over the study area and offer numerous micro-habitats for bryophytes. This is related to the characteristics of Gotjawal. We consider that more detailed studies should be conducted on regional scales to establish the bryophyte flora of Gotjawal and the evergreen broad-leaved forests of Jejudo Island.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.1 s.139
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• pp.50-56
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• 2005

The performance of Traditional Korean Fishing Boat is surveyed based on Report on Investigation of Korean Fishing Boat. The characteristics of Traditional Korean fishing Boat of hull form, rudder, sail are studied from the view point of modern sailing boat design. As a result we find her hull form is an excellent candidate of mother ship for modern boat design and the great sized rudder of Traditional Korean Fishing Boat makes a role of the centerboard of modern sailing host. And also we find the sail of Traditional Korean fishing Boat is more useful for sailing against the wind direction than an ordinary Lug sail.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.584-588
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• 1997

Lots of forginfs used in automobile and aerospce industries are made in hot or cold working conditions, depending on the size and shape of a product. Usually the die design for new items has been first made on the basis of experiences and many know-hows accumulated in the company and then slightly modified through trial and error method to get the desired forgings without defects. Most of drawings at the die design stage have been manually drawn, butrecently some of forging companies have begun to apply a computer-aided drafting technique to the die design for reducing drafting time as well as repeatedly utilizing standardized parts form registerd data base. In this paper the automated die design technique for forward extrusion of axisymmetric forgings is developed by using AutoLISP language. For this study the representative die system is determined form the investigation of several types of forging dies being currently employed in the metal forming field and the design rules for cold extrusion die are summarized and programmed on a personal computer. A few design examples of forward extrusion die are given and discusses.

• Journal of the Korean Ceramic Society
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• v.27 no.3
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• pp.329-336
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• 1990

In this investigation, bar-shaped specimens which consisted of three layers are prepared to study the effects of residual compressive stress on the mechanical properties in ZTA. The outer layers contained Al2O3 and unstabilized ZrO2 and the central layer contained Al2O3 and stabilized ZrO2(with 5.10wt% Y2O3). When cooled from the sintering temperature, some of zirconia in the outer layers transformed to the monoclinic form while zirconia in the central layer was retained in the tetragonal form. The transformation which induces to dilatational expansion led to the estabilishmenet of compressive stress in the outer layers and balances tensile stress in the central layer. Decrease of outer layer thickness(for a fixed total thickness)increases residual compressive stress. Because of residual compressive stress in the outer layers, the fracture toughness of outer layers of 3-layers composite is 10.21 Mpam1/2, which is increased to 25% above in comparison with 1-layer specimens in ZTA. Also, the 3-layers composite is believed to exhibite greater fracture resistance in contact damage environment from thermal shock test.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.2 no.2
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• pp.93-103
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• 1979

As principles of our country's Business Enterprises Account are being developed, Customs of Business Enterprises Account are in the state of change and then Principles of that are in revision. According to systematizing contents of such a principle of Business Enterprises Account, having made an analysis and Investigation from versatile situation, I can deprive of the following conclusions from above facts. 1. The prelude of a general principle involves compulosory character like a forced law rather than a theoretical teaching of original character. 2. Because of making much of supply of account information, To make mistakes, emphasis on function of an information, on the other side, being apt to disregard control function of original account. 3. There is no such a mutual relation as theoretical systematic form among general rule, a profit-and-loss account, balance sheet and drawing principle. These rules which don't form gradual structure are prescribed respectively according to business like necessity. 4. An overall contents of account principle are regarded as principle near financial account rather than the Pivot of administration account. In the future, The whole academic world of account and business practice should become the idealistic account principle with lots of study and effort.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2003.11a
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• pp.265-270
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• 2003

This expressway passing the address region that is sightseeing of our country must consider in what do a convenience sincerity chase and a cultural side view. A region with development possibility and a spinoff about a cultural element must hold consideration at the same time to a sightseeing resort. This route that passed Gang-Reung, Yang-Yang, Sok-cho was connecting an obstetrics acid, and accessibility along investigation was a hard place. In this region, a classic house is tying scattered, and JeonSaCheong inviting an ancestral mortuary tablet is appearing. The private house was divided during a classic house by using typical Gangwon to the room where a floor was introduced by house with several wings Korean floor heater center form. A characteristic form a characteristic change was appearing on each rooms and structure, a plane according to the times, and to execute extension with a lease in a direction too was able to be seen, and Confucianism a little culture very remained in construction, and a memorial service space, a closet were able to be seen. Also, this local high house had a lot of regions composed of a relative and was with doing in the village that did to these house several houses.

• Architectural research
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• v.15 no.2
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• pp.87-94
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• 2013

Throughout the history of architecture, sometimes the main focus of design was determined by a particular visual representation method, and other times a particular form of visual representation method was required by perception of a particular architectural issue or an architectural form or idea. That is why the visual representation method of architects becomes an important means of reading the flow of idea and thinking behind architecture. This study is an investigation on the relation between architectural thinking and visual representation method expressed through the conceptual drawings by avant-garde architects of the 1970s and 80s, a period of the emergence of postmodernism. Rather than proving the objective reality regarded important by traditional architectural drawing, attempts are made to express the design concept in which the project has its base. Such interpretation and explanation regarding the concept become the main interest of the drawing. It is not that the architecture itself was not expressed in the contents, but it may not be the main subject of expression in the drawing. The value of architectural drawing recovers its value as an art work in itself, as a means of communication, and as an important conceptual tool in the design process. It can be seen that the visual representation method in postmodern architectural drawings is breaking free of the traditional objective depiction of matter and is changing and developing as a design tool of the architect.