• Journal of the Korean Home Economics Association
• /
• v.36 no.9
• /
• pp.107-125
• /
• 1998

Focusing on 'reuse' with a view to the importance of unused cloths, this paper investigates the aspects of consumers' recycling attitudes regarding the cause and treatment of unused clothes. This research examines the responsibilities for recycling from the standpoint of consumers, and shows their requirements and advice to consumers themselves, clothing companies as the subject of production and the government and society. Considering the pattern of clothing life, this research deals with housewives who live I Seoul, Sung-nam and Choong-ju. After several pretests, the content and format of this questionnaire is revised and added. This investigation is carred by individual interviews and reponders' filling-out, from 24 November 1997 to 5 January 1998. Among the total 1,200 questionnaires, 1,150 sheets are taken back, but only 1,132 are available to analysis. The results are as follows: Most of all, among the causes of unused clothes, the problem of clothes itself is stemmed from the more responsibility of clothing companies rather than consumers'. From production to sale the companies, considering environment and recycling, should choose proper cloth material and adequate design. And then they require the consumers' attention to laundry and conservation. More important, consumers' attitudes should be changed because consumers themselves, in fact, recognize their responsibilities for recycling of clothing, from the questionnaire. After all, the recycling of clothing should lead to reduction of unused clothes as a fundamental solution. When it comes to unused clothes, its elimination pays more money and needs specialization. Moreover, citizens should participate in the problem independently and more information on the policies of recycling should be well-informed.

• Restorative Dentistry and Endodontics
• /
• v.41 no.4
• /
• pp.310-315
• /
• 2016

Two case reports describing a new technique of creating a repositionable piezoelectric bony window osteotomy during apicoectomy in order to preserve bone and act as an autologous graft for the surgical site are described. Endodontic microsurgery of anterior teeth with an intact cortical plate and large periapical lesion generally involves removal of a significant amount of healthy bone in order to enucleate the diseased tissue and manage root ends. In the reported cases, apicoectomy was performed on the lateral incisors of two patients. A piezoelectric device was used to create and elevate a bony window at the surgical site, instead of drilling and destroying bone while making an osteotomy with conventional burs. Routine microsurgical procedures - lesion enucleation, root-end resection, and filling - were carried out through this window preparation. The bony window was repositioned to the original site and the soft tissue sutured. The cases were re-evaluated clinically and radiographically after a period of 12 - 24 months. At follow-up, radiographic healing was observed. No additional grafting material was needed despite the extent of the lesions. The indication for this procedure is when teeth present with an intact or near-intact buccal cortical plate and a large apical lesion to preserve the bone and use it as an autologous graft.

• Journal of Powder Materials
• /
• v.9 no.4
• /
• pp.267-272
• /
• 2002

The production of micro components is one of the leading technologies in the fields of information and communiation, medical and biotechnology, and micro sensor and micro actuator system. Microfabrication (micromachining) techniques such as X-ray lithography, electroforming, micromolding and excimer laser ablation are used for the production of micro components out of silicon, polymer and a limited number of pure metals or binary alloys. However, since the first development of microfabrication technologies there have been demands for the cost-effective replication in large scale series as well as the extended range of available material. One such promising process is micro powder injection molding (PIM), which inherits the advantages of the conventional PIM technology, such as low production cost, shape complexity, applicability to many materials, applicability to many materials, and good tolerance. This paper reports on a fundamental investigation of the application of W-Cu powder to micro metal injection molding (MIM), especially in view of achieving a good filling and a safe removal of a micro mold conducted in the experiment. It is absolutely legitimate and meaningful, at the present state of the technique, to continue developing the micro MIM towards production processes for micro components.

• Journal of Periodontal and Implant Science
• /
• v.28 no.2
• /
• pp.281-291
• /
• 1998

Chitosan is a biodegradable and non-toxic material with a molecular weight of 800-1,500Kd which can be obtained in various forms with extraordinary chemical structures and biological characteristics of which enables it to be used in many fields as a biomaterial. Ion irradiation is a useful tool to modify chemical structures and physical properties of high molecular weight polymers. The basic hypothesis of this study is that when surface properties of chitosan in a sponge form are modified with ion beam-irradiation and cell adhesion properties of chitosan would improve and thereby increase the regenerative ability of the damaged bone. The purpose of this study was to illuminate the changes in the cytocompatibility of chitosan sponges after ion beam-irradiation as a preliminary research. Argon($Ar^+$) ions were irradiated at doses of $5{\times}10^{13}$, $5{\times}10^{15}$ at 35 keV on surfaces of each sponges. Cell adhesion and activity of alkaline phosphatases were studied using rat fetal osteoblasts. The results of this study show hat ion beam-irradiation at optimal doses($5{\times}10^^{13}\;Ar^+\;ion/cm^2$) is a useful method to improve cytocompatibility without sacrificing cell viability and any changing cell phenotypes. These results show that ion beam-irradiated chitosan sponges can be further applied as carriers in tissue engineering and as bone filling materials.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2006.11a
• /
• pp.117-121
• /
• 2006

This study intends to suggest the effective methods for water leakage prevention around the windows in stone works to up-grade the outdoor public space that has been taken much portion of apartment housing trends. The subjects of the study was selected among the domestic subcontractors of stone works. There are four methods for water leakage prevention around the windows; Firstly, the painting water-proof method after the masonry. Secondly, the urethane water-proof method after galvanizing panels on the gap. Thirdly, the separation method between stone and substructure and the last one is water-proof method that they put some water-proof screen between stone and substructure with the EPDM sheets. According to the analysis of the water-proof effects, constructability and planning, we could approach to conclusion that the most influent items to the water-leakage are the filling material's deformation, the state of oxygenation and deterioration of work skill. Among the water-proof methods in construction the EPDM sheet is most excellent water-proof method to meet the technical conditions. However, we have to apply it to stone works as a water-proof method for the decrease of the leakage defects after standardizing the materials, test and construction skill because there are many work skills according the subcontractors.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2018.11a
• /
• pp.25-26
• /
• 2018

Various concrete material technologies and new materials have been developed in accordance with the advancement of buildings. As part of these new technologies, light transparent concrete, which was invented by Hungarian architect Aron Losonczi and attracted worldwide attention, has a technique of arranging optical fiber inside concrete and transmitting the light from exterior to concrete to show silhouette inside. However, due to many disadvantages, application to the field was limited and commercialization was not easy. In Korea, Light Emotion Friendly Concrete has been developed for commercialization. In order to solve the degradation of construction performance caused by the arrangement of expensive optical fiber, which is pointed out as a disadvantage of translucent concrete, It converts expensive fiber into low cost acrylic rod, easy to arrange, pre-assembled to form and post-cast. Therefore, this study aims to improve the mechanical properties of LEFC and to derive optimal combination.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2005.05a
• /
• pp.174-179
• /
• 2005

In the super slow speed die casting process, the casting defects due to melt flow should be controlled in order to obtain sound casting products. The casting defects that are caused by molten metal were cold shut formation, entrapment of air, gas, and inclusion. But the control of casting defects has been based on the experience of the foundry engineers. The calculation of simulation can produce very useful and important results. The calculation data of die casting process condition from the computer simulation by the Z-CAST is made to insure that the liquid metal is injected at the right velocity range and that the filling time is small enough to prevent premature solidification. The parameters of runner shape that affected on the optimized conditions that was calculated with simple equation were investigated. These die casting process control techniques of automobile valve body mid-plate have achieved good agreement with the experimental data of tensile strength, hardness test, and material structure photographies satisfactory results.

• Journal of the East Asian Society of Dietary Life
• /
• v.5 no.3
• /
• pp.317-337
• /
• 1995

"Sinsulro(신선로)" is the famous soup of Cho-sun Dynasty Royal Cuisine, and the original food name is "Yulgujatang(열구자탕)". The first record is on [Sumunsasul] (1740) and the origin history related with Hirang-Jung is on [Headongjukji] and [Chosunyorihak]. From the analysis with Royal banquet menu and 16 kinds of old culinary literatures, "Sinsulro" are contained 54 and 70 material items and used variety cooking methods. Soup base of "Sinsulro" is well boiled meat, shank, brisket, stomach and intestine of beef with water, Some of beef is made meatball and seasoned raw meat. Beef marrow and tripes and liver are sauted with egg. Dried abalone and sea cucumber are soaked in water and then cutting slices after well boiled. Sliced white fish fillet are sauted with egg. Egg white and egg yolk made to thin sheet on pan with oil. Dropwort made to one sheet with flour and egg. Radish are boiled with meat soup and other vegetable are cooked with boiled or sauted. Seeds of pinenut, gingko, walnut are used of decorative seasonings. Filling mehtods of the Sinsulro casserole, the first layer is seasoning raw beef meat, 2nd layer is cooked slice of meat and radish, 3rd layer is rectangle pieces of egg sheet and sauted fish and intestines of beef. The top layer is decorated with meatball and naked nuts. After hot soup is poured until top of the materials, buning charcoal put into the center fire place and then served.o the center fire place and then served.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.24 no.2
• /
• pp.383-404
• /
• 1997

In this study, we tried to compare the effect of glass inserts on marginal leakage of composite resin restoration by comparing with that of several filling methods. The results obtained from this experiment were as follows ; 1. The degree of microleakage measured in glass inserts group was generally lower than that of the other groups. Statistical analysis showed significant intergroup difference between glass inserts and one complete unit, pre-polymerized composite resin ball(P<.05), but no significant difference between groups of glass inserts and increments(P>.05). 2. Scanning electron microscopic observation showed relatively large gap around resin-tooth interface in specimens restored the method of using the one complete unit and pre-polymerized composite resin ball whereas a denser and tighter was observed in increments and glass inserts group. Generally the gingival margin was shown to have better bonds than the occlusal margin in specimen of all groups. 3. In the present experiment, methods using the techniques of glass inserts and increments were evaluated to be superior to those of one complete unit, pre-polymerized composite resin ball in the aspect of microleakage. However, the result of this study could not determine the superiority of the use of glass inserts over incremental method. Besides the physical properties observed in this study, the practical aspect of clinical convenience should be considered in determining the selection of material.

• Steel and Composite Structures
• /
• v.1 no.2
• /
• pp.171-185
• /
• 2001

The design of tall buildings has recently provided many challenges to structural engineers. One such challenge is to minimise the cross-sectional dimensions of columns to ensure greater floor space in a building is attainable. This has both an economic and aesthetics benefit in buildings, which require structural engineering solutions. The use of high strength steel in tall buildings has the ability to achieve these benefits as the material provides a higher strength to cross-section ratio. However as the strength of the steel is increased the buckling characteristics become more dominant with slenderness limits for both local and global buckling becoming more significant. To arrest the problems associated with buckling of high strength steel, concrete filling and encasement can be utilised as it has the affect of changing the buckling mode, which increases the strength and stiffness of the member. This paper describes an experimental program undertaken for both encased and concrete filled composite columns, which were designed to be stocky in nature and thus fail by strength alone. The columns were designed to consider the strength in axial compression and were fabricated from high strength steel plate. In addition to the encased and concrete filled columns, unencased columns and hollow columns were also fabricated and tested to act as calibration specimens. A model for the axial strength was suggested and this is shown to compare well with the test results. Finally aspects of further research are addressed in this paper which include considering the effects of slender columns which may fail by global instabilities.