• Journal of Korean Society of Steel Construction
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• v.18 no.5
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• pp.543-551
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• 2006

Cold-formed steel studs that are being used as load-bearing members of wall panels for steel houses have a problem with their insulation due to the heat bridging of their web. Some additional thermal insulating materials should be used. To solve this problem, the new-concept hybrid stud, which consists of a galvanized steel sheet (t = 1.0 m - 12.0 m) and a GFRP panel (t = 4.0-6.0 mm), has recently been developed. An investigation on the structural behavior and the strength capacity of this new hybrid stud has been conducted so that it can be used in load-bearing wall panels of residential buildings. This paper describes the axial compression-torsion test results of the hybrid studs under both axial compression and torsion using ATTM. The main factors of the test were the stud length, the magnitude of the initial compressive force, and the loading method of the monotonic or cyclic loading. The torsion was applied increasingly while the initial compression was kept constant to the failure of the hybrid section. The advanced analysis results obtained form the finite element procedure that considered the material properties of the high-strength galvanized steel and the GFRP were compared with the test results for verification.

• Journal of Korean Society of Steel Construction
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• v.22 no.2
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• pp.151-160
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• 2010

The number of cases of collapsed plastic greenhouses in farmlands has increased due to the heavy local snowfall caused by extraordinary atmospheric phenomena. Consequently, the economic losses of farmers have also increased. However the government policy in relation to damage pretension is insufficient and collapse case is repeated every year. The main reason for frame collapse is that the moment capacity of a steel pipe is not sufficient to resist a heavy snowload. In this study, experiments were conducted on the current frame system of a greenhouse with a tension tie. The frame consisted of two sections(${\phi}25.4{\times}1.5$, ${\phi}31.8{\times}1.5$), and its span length was 6.5 m. A temporary tension tie using a steel wire and a fabric rope was connected to the two joints, to which a curved beam and a straight column were connected. The pretension force was applied at the tension tie, and a vertical force simulating snowfall was applied until failure. The fabric rope frame increased the load-carrying capacity by 10-45% compared to the normal frame without a tension tie, and the steel wire frame increased the load-carrying capacity by 58-73% compared to the normal frame without a tension tie. Steel wire was found to be more effective as far as strength is concerned, but its connection details and pretension application are more difficult and complicated than those of the fabric rope. The test results thus show that the fabric rope is more preferable.

• Tuberculosis and Respiratory Diseases
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• v.62 no.6
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• pp.516-522
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• 2007

Background: Postoperative pulmonary complications are important problems that prolong the length of the hospital stay and increase patient mortality. However, our knowledge of the postoperative factors that increase the risk of these complications is less than complete. Methods: We conducted a prospective study to determine the risk factors for postoperative pulmonary complications. A total of 199 patients were referred to the Pulmonology Department for preoperative pulmonary evaluation. We reviewed the perioperative variables according to the National Surgical Quality Improvement Program (NSQIP). Postoperatively, we collected data on the occurrence of postoperative pulmonary complications and we evaluated the relationship between the perioperative variables and outcomes. Results: Twenty two patients (11%) had pulmonary complications; 6 had respiratory failure, 4 had pneumonia, 13 had pleural effusion and, 2 had atelectasis. Five variables were statistically significantly associated with pulmonary complications on the bivariate analyses. Multiple logistic regression analyses revealed that three of these variables were independently associated with an increased risk of pulmonary complications; a high cardiac risk index (OR 16.5, p=0.002), emergency surgery (OR 10.3, p=0.017), and thoracic/abdominal surgery (OR 3.8, p=0.047). Conclusion: The risk factors for postoperative pulmonary complications are a high cardiac risk index, emergency surgery and thoracic/abdominal surgery.

• Journal of Korean Public Health Nursing
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• v.16 no.2
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• pp.304-314
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• 2002

A survey was conducted from September 15 to December 15 2001. Structured questionnaires were mailed to school nurses in 607 elementary schools around the country in order to determine the current status of anti-smoking education in elementary schools. The result were as followers 1. Of the 607 schools, 535 $(88.1\%)$ offered smoking-prevention education. By region, Jeju-do $(100\%)$ topped the list, followed by Seoul $(90.3\%)$, Gyeongsang-do$(90.2\%)$, Jeolla-do$(88.9\%)$, Gangwon-do $(87.8\%)$, Chungcheong-do $(84.6\%)$, and Gyeonggi-do $(81.4\%)$. 'Recognition of the need for anti-smoking program $(86\%)$' was a major motivation for initiating the program, while 'too much workload $(46.4\%)$' was cited as a main reason for the failure to do so. 2. The classes were offered mostly for 6th-grade students $(87.8\%)$, while $9.0\%$ and $2.0\%$ were implemented at 5th- and 4th- grades, respectively. 3. $49.1\%$ of the classes offered lasted one hour, while $31.8\%$ involved a two-hour program. 4. Programs were mainly about smoking-related diseases, habitual nature of smoking, impediment to growth and development, etc. 5. Audio-visual lecture $(46.5\%)$ was most frequently used as a method of education, followed by lecture. 6. $72.7\%$ of the programs used classroom as a unit of education, while collective education by sex or by grade accounted for $22.6\%$. 7. Video $(51.0\%)$ was the most popular medium for education, while computer ranked second with $26.5\%$. 8. $92.5\%$ of the education was offered by school nurses. 9. $99.2\%$ of school nurses responded in favor of anti-smoking programs. with $60.1\%$ of them answering that such education is a must. 5th grade was the most commonly cited grade for the initiation of the programs, followed by 4th grade and 6th grade. $33.2\%$ picked two hours as the most appropriate length of the program at the elementary school level. while $25.1\%$ chose 3 hours out of the range of 1-11 hour(s). 10. With regard to the evaluation by school nurses on smoking-prevention program, more than $30\%$ felt that hours of education, education materials, medium of education, interests of other teachers, interests of school authorities, etc. were inadequate or insufficient.

• Journal of the Korea Concrete Institute
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• v.22 no.5
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• pp.703-710
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• 2010

Reinforced concrete beams of existing structure often encounter insufficient shear problems for various reasons. Application of steel plates is one of widely used methods for shear strengthening of reinforced concrete beams that are insufficient of shear capacity. This study presents test results on strengthening shear deficient RC beams by external bonding of vertical and diagonal slit type steel plates with anchor bolt. Test parameters are width, interval, angle and length of slits with anchor bolt. The purpose was to evaluate the failure modes and shear capacities for RC beams strengthened by various slit type steel plates with anchor bolt. The results showed that the slit type steel plate specimens strengthened by adhesive bonding and bolting failed in shear fracture modes at maximum load. Flexural crack first occurred on the tension face of beam and then inclined cracks occurred on the shear span. Finally, slit type steel plates strengthened by adhesive bonding and fastening bolts managed to delay abrupt debonding and didn't detach fully from main body of RC beam.

• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.809-820
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• 2008

A new modified full scale double tee slabs with the length of nib plate - 1,500 mm were suggested, designed, and experimentally evaluated up to the loading of flexural failure. This slabs were composed of the tee section which was same to original PCI double tee and the plate section which was modified in a new shape, and the prestressing force was applied at the bottom of tee section only. This specimens were made from the domestic precast factory. The safety and serviceability of the modified nib plate with the dapped ends were evaluated up to the ultimate flexural strength of tee section. As the experimental loading increased, the flexural crackings developed first in the bottom of the slab and they changed to the increased flexural shear and inclined shear crackings in the nib and dapped portion of the double tees. The suggested modified double tee slabs failed in ductile above the design loading with many evenly distributed flexural crackings. The thickness of nib plate - 250 mm does not show any cracking under the service loading and show several minor flexural cracking up to the ultimate state of tee portion. The proposed specimens were satisfied with the strength and ductility requirements in the design code provisions in the tests. Additional experimental tests are required to reduce the depth and tensile reinforcement of nib plate concrete for the practical use of this system effectively.

• Geotechnical Engineering
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• v.12 no.2
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• pp.71-84
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• 1996

In order to investigate the influence of slanting angle of reticulated root piles(RRP) on their bearing capacities, model tests of compressive and uplift loads on RRP with different slanting angles, which were installed in sandy soils with a relative density of 47%, were carried out. Each pile which is made of a steel bar of 5mm in diameter and 300mm in length, is coated with sand to be 6.5mm in diameter. One set of RRP consists of 8 piles which are installed in circular patterns forming two concentric circles, each of which has 4 piles. Slanting angles of RRP for load tests are 0$^{\circ}$, 5$^{\circ}$, 10$^{\circ}$, 15$^{\circ}$, 20$^{\circ}$, and 25$^{\circ}$. In addition, compressive load tests on circular footing whose diameter is the same as the outer circle of RRP were carried out. Test results show that maximum load bearing capacities of RRP by regression analysis are obtained at about 12$^{\circ}$ and 13$^{\circ}$ of slanting angles for compressive and uplift load tests, respectively. Maximum compressive bearing capacity is estimated to be 13oA bigger than that of the vertical RRP and 95% bigger than that of surface footing. Maximum uplift capacity is estimated to be 21% bigger than that of the vertical RRP. And it can be appreciated that increasing the slanting angle makes the load -Settlement behavior more ductile.

• Journal of the Korean Geotechnical Society
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• v.33 no.8
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• pp.5-16
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• 2017

When a lateral load is applied to a short pile whose embedded depth is relatively smaller than its diameter, an overturning failure occurs. To investigate the behavior of laterally loaded short piles, several model tests in laboratory scales had been carried out, however the behavior of large moment carrying piles for electric poles, traffic sign and road lamp, etc. have not been revealed yet. This paper deals with the real-scale load tests for 750 mm diameter short piles. To simulate the actual loading condition, very large moment was mobilized by applying lateral loads to the location 8 m away from the pile head. Three load tests changing the pile embedded lengths to 2.0 m, 2.5 m, and 3.0 m were carried out. The test piles overturned abruptly with very small displacement and rotation before the failures. These brittle failures are in contrast with the ductile failures shown in the former model tests with the relatively smaller moment to lateral load ratio. Comparisons of the test results with three existing methods for the estimation of the ultimate lateral capacity show that the method assuming the rotation point at pile tip matches well when the embedded depth is small, however, as the embedded depth increases the other two methods assuming the inversion of soil pressure with respect to rotation points in pile length match better.

• The Journal of Korean Academic Society of Nursing Education
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• v.6 no.2
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• pp.171-185
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• 2000

The twenty-first century may be said to be entering into a specialized qualification age to meet the needs of new technical innovations such as environmental changes, demographical changes, changes in the constitution of diseases, changes in the needs of the national health, reforms of information and knowledge, etc., which requires the provision of competitive services that can fulfill the high level needs of consumers. In consequence, it is needed to apply a practical nursing model that can serve as a guide for healthy society and to secure the sphere that can affect nursing policy-making by keeping pace with the changing environment. Furthermore, it is also urgent to expand more the activity sphere of nurse specialists with authority and autonomy, establish their legal foundation, establish a qualification accreditation system for nurse specialists, and develop educational programs. In Korea, the law relative to organ transplant past the national assembly on February 9, 2000, legally acknowledged brain death, which indicated to us the emergence of an age of organ transplant. Therefore, it necessitates to find out those of brain death from whom organ transplant is feasible in clinical practices, with their families' consent link to those terminal organ failure patients who are in need of an organ, and mediate both parties so that smooth transplant can be accomplished. A series of these complicated procedures require systematically trained specialists with high level techniques of organic management. With this in mind, this study was conducted on 69 clinical nurse specialists for organ transplant, accredited by the hospital, who are in active service in clinical practices. The resultant findings were revealed, as follows: 1. The qualifications of clinical nurse specialists for organ transplant should be accredited by Ministry of Health and Welfare or Korea Nurses Association. 2. The validity of qualifications should be for three years, and their renewal should be based on marks of a supplemental training or an education course for more than 12 hours a year. 3. The qualification of the clinical nurse specialist necessitates theoretical lectures and practices on those nurses who have had clinical experience in the pertinent field. 4. The course of training is required to be one year in the length of training and take more than 20 credits (320 hours) and 5 credits (240 hours).

• Journal of Bio-Environment Control
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• v.26 no.3
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• pp.215-220
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• 2017

This study was conducted to improve the insufficiency of fruit vegetable grafting system developed by National Institute of Agricultural Sciences, Rural Development Administration. When the rotary blade cut the stem of scions and rootstocks, the grafting failure at curved cutting surfaces happened. The cutting depth of a tomato seedling by a rotated cutter was calculated 0.11 mm even when the cutting arm length and the maximum stem diameter were 50 mm and 5 mm, respectively. Mathematical analysis and high-speed photography showed that there was no problem by cutting in straight the stem of scions and rootstocks. The compression test of seedling stems to design the optimal shape of gripper showed that stems were not completely restored when they were compressed above 0.8 mm and 0.6 mm in case of rootstocks and scion, respectively. This study found that the bending angle of stem of tomato seedlings at the grafting period was 10 degree on average. The optimal gripper finger was the edge finger type which could be precisely set center point by adjusting the distance between fingers. In addition, it was found that most of seedling could be grasped without damage when the finger-to-finger distances is set to 2.5 mm for scion and 3.0 mm for rootstocks and finger are coated by 1 mm-thick flexible material.