• Advances in aircraft and spacecraft science
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• v.1 no.2
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• pp.233-251
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• 2014

Each aircraft have to be certified for a specified level of impact energy, for assuring the capability of a safe flight and landing after the impact against a bird at cruise speed. The aim of this research work was to define a scientific and methodological approach to the study of the birdstrike phenomenon against several windshield geometries. A series of numerical simulations have been performed using the explicit finite element solver code LS-Dyna, in order to estimate the windshield-surround structure capability to absorb the bird impact energy, safely and efficiently, according to EASA Certification Specifications 25.631 (2011). The research considers the results obtained about a parametric numerical analysis of a simplified, but realistic, square flat windshield model, as reported in the last work (Grimaldi et al. 2013), where this model was subjected to the impact of a 1.8 kg bird model at 155 m/s to estimate the sensitivity of the target geometry, the impact angle, and the plate curvature on the impact response of the windshield structure. Then on the basis of these results in this paper the topic is focused about the development of a numerical simulation on a complete aircraft windshield-surround model with an innovative configuration. Both simulations have used a FE-SPH coupled approach for the fluid-structure interaction. The main achievement of this research has been the collection of analysis and results obtained on both simplified realistic and complete model analysis, addressed to approach with gained confidence the birdstrike problem. Guidelines for setting up a certification test, together with a design proposal for a test article are an important result of such simulations.

• Journal of Korea Port Economic Association
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• v.25 no.1
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• pp.169-190
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• 2009

In order to establish whether any charterparty terms are incorporated into the bill of lading, the first necessity is to specify the charterparty alluded to the incorporation clause in the bill of lading. However, this becomes a potential problem where the date of a charterparty is not inserted on the face of the bill of lading in case a vessel is in operation under a number of charterparties. Over many years this issue has frequently been raised before the English courts, but it is still causing problems. The purpose of this study is to examines the several English authorities which dealt with the issue relating to the specification of charterparty incorporated into the bill of lading and to present some interpretation rules and the order of priority. As a result, the comparative analysis of English authorities shows that they failed to give dear guidance on this issue. This article therefore suggests four interpretation rules such as the precedence of a B/L's face, the rule of appositeness, surrounding circumstances, the contra proferentem rule and shows that the precedence of a B/L's face is most applicable for all parties.

• Journal of Preventive Medicine and Public Health
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• v.44 no.4
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• pp.141-148
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• 2011

Annual epidemics of seasonal influenza occur during autumn and winter in temperate regions and have imposed substantial public health and economic burdens. At the global level, these epidemics cause about 3-5 million severe cases of illness and about 0.25-0.5 million deaths each year. Although annual vaccination is the most effective way to prevent the disease and its severe outcomes, influenza vaccination coverage rates have been at suboptimal levels in many countries. For instance, the coverage rates among the elderly in 20 developed nations in 2008 ranged from 21% to 78% (median 65%). In the U.S., influenza vaccination levels among elderly population appeared to reach a "plateau" of about 70% after the late 1990s, and levels among child populations have remained at less than 50%. In addition, disparities in the coverage rates across subpopulations within a country present another important public health issue. New approaches are needed for countries striving both to improve their overall coverage rates and to eliminate disparities. This review article aims to describe a broad conceptual framework of vaccination, and to illustrate four potential determinants of influenza vaccination based on empirical analyses of U.S. nationally representative populations. These determinants include the ongoing influenza epidemic level, mass media reporting on influenza-related topics, reimbursement rate for providers to administer influenza vaccination, and vaccine supply. It additionally proposes specific policy implications, derived from these empirical analyses, to improve the influenza vaccination coverage rate and associated disparities in the U.S., which could be generalizable to other countries.

• Journal of Families and Better Life
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• v.22 no.1
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• pp.11-25
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• 2004

This study was conducted to explore the impacts of involvement in the Vietnam War on the self-esteem of the veterans in their later lives. In this study, 14 Korean male Vietnam War veterans from 55 to 63 years old were asked about the impacts of their war experiences on their self-esteem. From the analysis of the in-depth interviews the following conclusions were drawn: First, the veterans perceived that their self-esteem improved with both internal and external impacts of their activities in Vietnam. The internal aspects that improved the veterans' self-esteem were recalling their positive memories of Vietnam War, such as being on duty at a war front for the sake of our country, doing volunteer work for the villagers, and becoming a masculine heroic figure in the family legend. The external aspects were positive attitudes and responses toward their war activities from their family, friends, and neighbors. Second, they also felt persistently frustrated with their recurring memories of involvement in killing human beings, experiences of negative family and social responses, and the side effects of herbicidal cyanide they suffer. In this article, the following suggestions were made. First, standardized images and good-will episodes of the Vietnam War need to be provided by the government, in order to improve public images on the veterans. Second, intensive adjustment programs for the families of older veterans in special needs should be developed in collaboration with various veterans' societies and family counseling institutions, so that the spouses and children can be relieved from tension-laden contacts with the veterans and prevent violent incidents.

• Journal of Biomedical Engineering Research
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• v.25 no.6
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• pp.505-510
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• 2004

In this article, we present an automated system for adjusting the 6 degree of freedom (D.O.F.) circular fixator. The system includes a scheduling software to adjust the Hexapod Circular Fixator (HCF) and an automated strut with the ability of the multiple synchronized motion and independent motion. The HCF was designed to control a 6 D.O.F. Ilizarov fixator and it's mechanism. The HCF adjustment software evaluates each value of altered length of the HCF struts to correct the complex skeletal deformity by using the X-ray data of the patient. The data of HCF adjustment software feed into the automated strut system which provides the scheduled adjustment. Then, the automated strut is synchronized by input data. Also the data of HCF adjustment software can be used to adjust HCF without automated struts. The proposed HCF system was verified by experiments.

• Journal of Information Technology Services
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• v.9 no.3
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• pp.25-43
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• 2010

The speed and magnitude of mobile phone adoption is a recent worldwide phenomenon akin to those of the television in the middle of the 20th century and the Internet in the late 20th century. During the 2000s, mobile phone adoption was exploded and subscriptions reached 3 billion around the globe. Korea and Japan have been ahead of the rest of the world in introducing new handset and service capabilities. They were the first markets to launch 3G services and are currently the only markets to have achieved mainstream adoption of 3G with over one-third of customers in both markets subscribing to 3G services. The purpose of this article is to explore the cultural similarities and differences associated with mobile mail by presenting findings from a cross-cultural comparison of perceptions and uses of the technology. The results of the study are as follows：Of the characteristics that make up the mobile text-messaging service in Korea, a person's perceived ease of use and perceived enjoyment was found to have a positive effect on use attitude. Among the characteristics that make up a person's perceived ease of use, perceived enjoyment was found to have a positive effect on use intention. And use attitude was found to have positive effects on use intention. But, of the characteristics that make up the mobile text-messaging service in Japan, a person's perceived usefulness, perceived ease of use and perceived enjoyment were found to have a positive effect on use attitude. Among the characteristics that make up a person's perceived usefulness, perceived ease of use and perceived enjoyment were found to have a positive effect on use intention. And use attitude was found to have positive effects on use intention. This study contributes to telecommunications research by delineating the various stimuli to consider for successful technology acceptance in a global setting, which can account for differential impacts across regions. The findings of this study can assist telecommunications operators in formulating an effective region-specific strategy when launching a wireless data service in a particular environment.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.6
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• pp.1037-1045
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• 2001

This research is done to design and manufacture prototype clean room garments to improve the product yield of the clean room processing. To assist the research, other papers and references on the same subject were collected for analysis. Also the researcher made interviews with the workers at the clean room. The prototype garments made for this project was compared against the commercially available clean room garments used in the industry. A set of test was conducted to measure particle release from the garments. The prototype clean room garments was manufactured after having considered all the aspects stated above, and tested for the level of particle release. The test subjects performed 4 different movements(marching, arms stretch, squat and rise, and jogging) while wearing the prototype garments and commercially available clean room garments. Particle counts produced by each movement were measured. The data collected was statistically analyzed. The followings are the result of the test. 1) Overall, the prototype garments yielded less particle release.(p<0.001) 2) It showed greatest difference of particle counts for jogging(p<0.001) and squat and rise(p<0.001). In the arms stretch test. the prototype garments was also more effective in controling the particle, however, in the marching test. no significant difference was detected. 3) The prototype garments had less particle release in upper(p<0.001), middle(p< 0.001), and lower level(p<0.01) than the commercially available clean room garments. Manufacturing a new fabric for the clean room processing is important, but this research proves that the design of the clean room garments also determines the efficiency garments in the particle control. Therefore the same fabric can perform differently according to how it is designed. Improving the design will also improve the 7article control and reduce the cost of research. Eventually, the manufacturers will increase the product yield.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.5 s.170
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• pp.103-112
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• 2005

This paper presents one-axis high precision scanning system and illustrates the design of modified $X-Y-{\theta}$ stage as a tracker using VCM and commercialized air bearings for it. The scanning system for 100nm resolution is composed of the 3-axis stage and one axis long stroke linear motor stage as a follower. In this study a previous proposed and presented structure of VCM for the fine stage is modified. The tracker has 3 DOF($X-Y-{\theta}$ motions by four VCM actuators which are located on the same plane. So 4 actuating forces are suggested and designed to create least pitch and roll motions. This article will show about the design especially about optimal design. The design focus of this fine stage is to have high acceleration to accomplish high throughput. The optimal design of maximizing acceleration is performed in restrained size. The most sensitive constraint of this optimal design is heat dissipation of coil. There are 5 design variables. Because the relationship between design variables and system parameters are quite complicated, it is very difficult to set design variables manually. Due to it, computer based optimal design procedure using MATLAB is used. Then, this paper also describes the procedures of selecting design variables for the optimal design and a mathematical formulation of the optimization problem. Based on the solution of the optimization problem, the final design of the stage is also presented. The results can be verified by MAXWELL. The designed stage has the acceleration of about 5 $m/s^{2}$ with 40kg total mass including wafer chuck and interferometer mirror. And the temperature of coil is increased $50^{\circ}C$. In addition, the tracker is controlled by high precision controller system with HP interferometer for it and linear scaler for the follower. At that time, the scanning system has high precision resolution about 5nm and scanning resolution about 40nm in 25mm/s constant speed

• Korean Journal of Acupuncture
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• v.37 no.3
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• pp.203-208
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• 2020

Objectives : Since there are complex associations between diseases/symptoms and acupoints, one-to-one correspondence may not be the proper approach. Pattern identification has been being used as a clinical framework to make treatment decisions by extracting and synthesizing clinical data including patients' signs and symptoms. In this article, we propose two different models explaining the relationships between diseases and acupoints based on the branch treatment [Zhibiaofa] and the root treatment [Zhibenfa]. Methods : We explained the relationships between diseases/symptoms and acupoints from the example data from our previous study on traditional acupuncture point selection patterns for pain control. Diseases include low back pain, migraine, irritable bowel syndrome, osteoarthritis, ankle sprain, carpal tunnel syndrome, and dysmenorrhea, and acupoints included LI4, BL23, BL25, SP6, BL60, TE5, and CV4. Results : The relationships between diseases/symptoms and acupoints can be explained directly based on the branch treatment, and also can be explained indirectly through pattern identification based on the root treatment. Pattern identifications included both meridian-based pattern identification based on the spatial information of diseases and visceral organ-based pattern identification based on the characteristics of diseases. Conclusions : In the East Asian traditional medicine, Korean medicine doctors choose the most appropriate acupoints based either on the diseases/symptoms (i.e., branch treatment) or on the results of pattern identifications (i.e., root treatment). It is necessary to understand the two different approaches to choose specific acupoints for the targeted diseases.

• Journal of Korean Neurosurgical Society
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• v.60 no.5
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• pp.534-539
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• 2017

Objective : Patients with hematological malignancies frequently encounter spine-related symptoms, which are caused by disease itself or process of treatment. However, there is still lack of knowledge on their epidemiology and clinical courses. The purpose of this article is to review clinical presentations and surgical results for spinal involvement of hematologic malignancies. Methods : From January 2011 to September 2014, 195 patients (98 males and 97 females) suffering from hematological malignancies combined with spinal problems were retrospectively analyzed for clinical and radiological characteristics and their clinical results. Results : The most common diagnosis of hematological malignancy was multiple myeloma (96 patients, 49.7%), followed by chronic myeloid leukemia (30, 15.2%), acute myeloid leukemia (22, 11.2%), and lymphoma (15, 7.56%). The major presenting symptoms were mechanical axial pain (132, 67.7%) resulting from pathologic fractures, and followed by radiating pain (49, 25.1%). Progressive neurologic deficits were noted in 15 patients (7.7%), which revealed as cord compression by epidural mass or compressive myelopathy combined with pathologic fractures. Reconstructive surgery for neurologic compromise was done in 16 patients. Even though surgical intervention was useful for early paralysis (Frankel grade D or E), neurologic recovery was not satisfactory for the progressed paralysis (Frankel grade A or B). Conclusion : Hematological malignancies may cause various spinal problems related to disease progression or consequences of treatments. Conservative and palliative treatments are mainstay for these lesions. However, timely surgical interventions should be considered for the cases of pathologic fractures with progressive neurologic compromise.