The Effect of 3-Isocyanato-1-Propene on Adhesive Properties of UV-Curing Urethane/Siloxane Acrylate Resin.

We synthesized the urethane/siloxane acrylate oligomer from isophorone diisocyanate (IPDI), hydroxyl alkyl terminated polydimethylsiloxane and 2-hydroxyethyl acrylate (2-HEA). UV-curable resins were formulated from the synthesized oligomer, ethylene glycol phenyl ether acrylate (PHEA), 1,6-hexanediol diacrylate (HDDA), trimethylolpropane triacrylate (TMPTA) as a reactive diluent, 3-isocyanato-1-propene as an adhesion promoter and photoinitiators. The PET film was treated with plasma in order to introduce the functional group on the PET surface and the functional group was observed through X-ray photoelectron spectroscopy (XPS) and the Fourier transform infrared (FT-IR). The adhesion strength between the PET film and the UV-cured resin were increased by using the adhesion promoter. Also, the thermal stability, the modulus and surface hardness were increased, as the adhesion promoter was added.

Occupational deaths and injuries in the construction industry.

This study concerned with the characteristics of occupational deaths and injuries in the construction industry of South Korea. The national statistics of industrial accidents in the years 1991-1994 were extracted from the annual publications of the Ministry of Labor. These data were analyzed in terms of the size of company, age of injured person, work experience, accident type, injury type, injured part of body, and agency of accident. The results show that there are some patterns in the characteristics of occupational injuries of construction industry: (1) deaths occur more frequently in the older workers; (2) the most common type of accident is 'falls from a height'; (3) 'fracture' is the leading injury type; (4) the body sites most vulnerable to injury are the leg, foot and toe in the non-fatal injuries, while the head, face, and neck in deaths; (5) most of the accidents occurred from the temporary construction or fabric. The results also show that there are differences in accident characteristics between occupational deaths and nonfatal injuries. These findings identified in this study can be used to decide the accident prevention programs.

Hydrocarbon chain distribution of ether phospholipids of the ascidian Halocynthia roretzi and the sea urchin Strongylocentrotus intermedius.

The contents and compositions of the 1-O-alk-1'-enyl-2-acyl, 1-O-alkyl-2-acyl, and 1,2-diacyl glycerophospholipids in the muscle and viscera of the ascidian Halocynthia roretzi, and of the gonad of the sea urchin Strongylocentrotus intermedius, which are eaten to some extent in Alaska and in Asia, were analyzed by gas-liquid chromatography. 1-O-Alk-1'-enyl-2-acyl glycerophospholipids were found in all of the samples, accounting for 64.4-69.0% of the ethanolamine glycerophospholipid (EPL). By contrast, the levels of the 1-O-Alk-1'-enyl-2-acyl choline glycerophospholipids (CPL) were low (3.1-5.7%). CPL was rich in the 1-O-alkyl-2-acyl subclass amounting to 12.5-23.9% in the ascidian sample. The level of CPL in the sea urchin gonad was extremely high, amounting to 46.1%. The most prominent alkyl chains in the sn-1 position of CPL from the ascidian muscle were 16:0 (44.6%), 18:1 (26.5%), and 18:0 (10.7%), and of CPL from the sea urchin gonad were 18:0 (36.2%), 16:0 (33.0%), and 18:1 (17.8%). Unusually high levels of odd-numbered alkyl chains, e.g., 19:0 and anteiso 17:0, were detected in the CPL of all samples. The prominent alkenyl chains of EPL were 18:0 (69.4%), 16:0 (10.0%), and 18:1 (8.54%) (not counting the vinyl double bond) for the sea urchin gonad. Relatively high levels of 20:1 alkenyl chains were also present. The glycerol sn-2 positions contained high proportions of polyunsaturated fatty acids. Thus, 20:5n-3 (43.6%) and 22:6n-3 (20.1%) were most abundant in the alkylacyl CPL from the ascidian muscle and 20:5n-3 (54.9%) and 20:4n-6 (30.1%) in alkylacyl CPL from the sea urchin gonad. Despite a possible interconversion of the alkyl and alkenyl chains of each class of the ether phospholipids, they showed few features in common.

Contour representation of sway area in posturography and its application.

The representation of postural sway tendency in posturography is important to understand the features of body balance system and a variety of postural disorders. This study is concerned with the contour representation and analysis of postural sway trajectory in posturography. We propose two methodologies to derive the contour of postural sway based on the boundary points of sway area. An algorithm for finding the sway contour in each method was developed, and the experiments were performed to examine the computational efficiency between the methods proposed. Fourteen able-bodied men were asked to stand upright on a force platform to compare the numerical measures of sway shape with other quantitative sway measures used in previous research into balance. The results show that numerical measures of sway contour (area, perimeter, and complexity of sway shape) and radius length diagram can be used to describe the tendency of sway shape, whereas other quantitative sway measures represent the extent of sway amounts.

Respiration effect on standing balance.

An attempt was made to determine the effect of respiration on standing balance. Ten able-bodied subjects were asked to stand upright on a force platform and were asked to hold their breath after inspiration and after expiration, and to breathe regularly, 4, 6, and 8 respirations per 20 seconds. Sway was measured over 20-second periods with eyes open and eyes closed. The results show that both respiration and eye condition affect the sway distance of the center of pressure on body balance. The sway distance in holding breath after inspiration is significantly greater than in holding breath after expiration, and increasing the respiration rate produces a greater postural sway. Also, the grade of visual compensation for body balance is higher in the regular respiration condition than in breath holding. These findings are applicable for ergonomics, sports, and clinical situations.

Sex differences in anthropometry for school furniture design.

This paper is concerned with anthropometric dimensions of young Koreans and their interrelationships for school furniture design. Ten anthropometric measurements were taken from 1248 subjects, age range 6-17. The study investigated sex differences in interrelationships between body dimensions, to provide suitable sizes of chair and desk for boys and girls. The results showed that stature had a high relationship to body dimensions for school furniture design, and that there were significant sex differences in relationships between stature and the body dimensions. In particular, boys above 126 cm in stature required higher desk and chair heights than girls of the same stature. On the other hand, girls above 120 cm in stature required a larger depth and breadth of chair than boys of the same stature.