• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.20 no.10
• /
• pp.1061-1070
• /
• 2009

In this paper, we have designed TDL(True-time Delay Line) for eliminating beam-squint occurring in active phased array antenna with large electrical size operated in wide bandwidth, and have tested its electrical performance. The proposed TDL device is composed of 4-bit microstrip delay line structure and MMIC amplifier for compensation of the delay-line loss. The measured results of gain and phase versus delay state satisfy the electrical requirements, also P1dB output power and noise figure meet the requirement. To verify the performance of fabricated TDL, we have simulated the beam patterns of wide-band active phased array antenna using the measured results and have certified the beam pattern compensation performance. As a result of simulated beam pattern compensation with respect to the 675.8 mm size antenna which is operated in X-band, 800 MHz bandwidth, we have reduced the beam squint error of ${\pm}1^{\circ}$ with ${\pm}0.1^{\circ}$. So this TDL module is able to be applied to active phase array antenna system.

• Journal of Chest Surgery
• /
• v.31 no.3
• /
• pp.279-285
• /
• 1998

Exessive sweating of the palms and soles, is a psychologically and occupationally distressing and sometimes disabling condition. Hyperhidrosis is one of the common abnormalities in autonomic nervous system. There were no specific treatment on hyperhidrosis, so invasive thoracic sympathectomy via axillary thoracotomy or cervical approach had been used. Video-assisted thoracic surgery(VATS) is now mostly performed for treating of the palmar and axillary hyperhidrosis. From March 1996 to March 1997, 15 patients with bilateral palmar hyperhidrosis had been treated by the bilateral thoracic sympathectomy(T2, T3, T4) with thoracoscopic resection. The patient were evaluated preoperative and postoperative Digital Infrared Thermographic Imaging (DITI) at Kyung-Hee University Hospital. There were no case of the thoracotomy conversion. There were 3 complications ; pulmonary edema in 1 case, Horner's syndrome in 1 case, and gustatory hyperhidrosis in 1 case. More than half of the patients also had compensatory sweating in the lower abdomen, the buttocks, the back and the thighs. In conclusion, most of the patients were satisfied with the postoperative results of the thoracoscopic sympathectomy, including no more palmar and axillary sweating, less pain, better cosmetic appearances, decreased sweating of the face and soles. In addition, intraoperative temperature monitoring of the hands could estimate the successful thoracoscopic sympathectomy and the preoperative and postoperative Digital infrared thermographic imaging(DITI) could especially be the technique for the objective manifestation of the successful results of the thoracoscopic sympathectomy.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.8
• /
• pp.171-180
• /
• 2017

The purpose of this study is to determine an effective training method to improve sequela, since traumatic brain injury sequela is a major factor in determining the quality of life. Neurofeedback training was conducted for an adolescent who had experienced traumatic brain injury during his childhood and who had difficulty in cognitive learning and emotional aspects. The assessment of an adolescent was conducted using K-WAIS-IV intelligence test and QEEG brain wave analysis. In the neurofeedback training, T3 alpha wave compensation and T4 alpha wave inhibition training were performed 36 times for 30 minutes three times a week. In addition to the neurofeedback training, respiratory meditation was also made available to the adolescent. As a result, the adolescent showed a stable condition as indicated by taking a good sleep, reducing test anxiety, and satisfaction with final exam results. This study revealed the possibility for hidden physical and psychological problems arising due to childhood brain trauma. It has also recently been discovered that a more diverse set of tools can be found. In addition, these childhood traumatic brain injuries can be improved through brain training and meditation. The study finding is meaningful for its suggestion of a fusion method for developing mind and body therapy in terms of brain science.

• Journal of Chest Surgery
• /
• v.31 no.12
• /
• pp.1212-1216
• /
• 1998

Background: Recently thoracoscopic surgery is widely applied in thoracic surgical field and hyperhidrosis is one of the most frequently operated diseases. Material and Method: From June 1997 to February 1998, 30 patients with hyperhidrosis underwent bilateral thoracic sympathectomy under thoracoscopy at Inje University Sanggye Paik Hospital. There were 10 males and 20 females whose mean age was 22.42±6.84 years ranging from 17 to 51. All patients underwent bilateral thoracic sympathectomy under semi-sitting position and two 5 mm sized trocars were inserted. Result: Mean operation time was 52.32±11.72 minutes and the mean elevation of palmar temperature after sympathectomy was 2.17±0.47℃. Eighteen patients(60%) complained compensatory hyperhidrosis. All patients except one were able to discharge at the operation day or postoperative one day. There were no recurrence during follow up from 2 to 8 months(mean 5.30±2.17 months). Conclusion: Thoracoscopic sympathectomy is simple and effective technique in hyperhidrosis and widely applied indication will be necessary. We conclude that further discussion should be made about the resection area and method to get maximal effect and minimal side effect.

• Korean Business Review
• /
• v.19 no.1
• /
• pp.223-240
• /
• 2006

The purpose of this study is to review the current state of the transformational leadership and LMX approach to the study of leadership. Leadership research has witnessed a shift from traditional transactional models to a new genre of theories of transformational and charismatic leadership and LMX. Transformational leadership theories offer the promise of extraordinary individual and organizational outcomes. Leaders motivate followers to perform beyond expected levels by activating higher order needs, fostering a climate of trust, and inducing them to transcend their self-interest for the organization's sake. Numerous investigations point of the robustness of the effects of such leadership on individual and organizational outcomes such as job satisfaction, organizational commitment, and performance. LMX theory suggests that leaders do not use the same style in dealing with all subordinates, but rather develop a different type of relationship or exchange with each subordinate. These relationships range from those that are based strictly on employment contracts to those that are characterized by mutual trust, respect, liking, and reciprocal influence. LMX has been positively related to job satisfaction, productivity, and career progress of managers and negatively related to turnover and employee grievances. In conclusions, effective leaders link achievement of organizational goals to follower fulfillment of self-development goals, with the former advancing the latter.

• Journal of dental hygiene science
• /
• v.11 no.1
• /
• pp.47-53
• /
• 2011

The purpose of this study was identified about the self-perceived job stress and the relationship between turnover and job stress of dental hygienists'. This results were based for improved of job satisfaction of dental hygienists'. 214 dental hygienist in Ulsan and Kyung Nam areas were participated and this study was done from March to May in 2009. Results: In the job-related environmental characteristic, 57.5% of participant worked in dental clinic and 42.5% of participant worked in dental hospital. The majority of career year was 1~3 years, 42.5%. 38.3% of participant had turnover, and the majority of number of turnover was once, 45.1%. 33.6% of participant had 1,300,000~1,490,000 won/month, 49.5% of participant worked for 8~9hours/day and the major working service was assistant for general dental treatment, 70.1%. Younger dental hygienist had more stress about inappropriate compensation. Higher education and married dental hygienist had more stress about job demand. The number of turnover, workplace culture and experience of turnover were significantly related. In the job-related environmental characteristic, job demand, interpersonal conflict and a case of dental clinic were significantly related. Other effecting factors were interpersonal conflict in salary, organization system in working time, and working demand in conditions of 5day's working. Experience of turnover was influenced with interpersonal conflicts and the number of dental hygienist in the working place was related with job stress significantly.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.28 no.3
• /
• pp.269-276
• /
• 2012

Many researches have been published about the numerous factors related to the chewing ability of implant prosthesis. Most respective studies have concluded that the chewing ability of implant prosthesis is mostly fine compared to other type of prosthesis. However, some patients are not satisfied with their chewing ability of implant prosthesis. Therefore the neurologic factor, one of the factors related to dissatisfaction of chewing ability was reviewed in this study to understand the mechanism of action of mastication. Data was searched using the keywords; 'implant chewing ability, masticatory ability' in Pubmed database and reviewed. Definitions of chewing ability, factors of chewing ability are reviewed and the neurologic factor, one of the factors influencing on chewing ability, is reviewed. Mechanoreceptor of Periodontal ligament(PDL) is providing the mastication information to brainstem. Due to the absence of mechanoreceptions of PDL in implant, masticatory ability is decreased especially when chewing hard food. Masticatory muscles and mechanoreceptor in TMD may compensate the lack of mechanoreceptor of PDL in implants. Furthermore sensitivity of nerve fiber around peri-implant tissues may support the mechanoreception and sensory reaction in the implant mastication. However, further studies should be conducted to prove the relationships between neurologic factors and mastication.

• Korean Journal of Construction Engineering and Management
• /
• v.11 no.2
• /
• pp.94-105
• /
• 2010

Recently, resettlement problems of low income groups in the urban regeneration area have been issued in Korea because they have no capability to purchase (or lease) redeveloped housing (or apartment). There are several approaches for supplying affordable housing and one of these is the bidding system which can reduce construction cost. However, the lowest bidding system has many problems such as dumping and substandard quality. In this context, this study proposed bidding system based on technical proposal applying the concept of the lowest total combined bid price for optimization of bid price, reduction of construction cost and period, and maintenance of suitable quality. This bidding system embraces the best value and cost plus time concept on the basis of an improved lowest price bidding system. It consists of the following components: work unit based, project unit based, and period reducing technical proposals. The proposed bidding system for determining bidders are designed to evaluate the adequacy of each technical proposal in the order of the combined minimum price in an effort to effectively optimize bid prices and reduce the construction periods, as well as to maintain a minimum appropriate quality.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.23 no.6
• /
• pp.740-747
• /
• 2012

An Active Electronically Scanned Array(AESA) radar required necessarily as the Fire Control Radar(FCR) of recent fighters has ununiform detection range with regard to scan angle due to scan loss. Although the compensation method of scan loss in an AESA radar with variable dwell time is investigated, the effectiveness of the method in a fighter FCR with multi-function such as search, track, and missile guidance within limited resources should be considered systematically. In this paper, uniform search performance of an AESA radar using variable dwell time with regard to scan angle is derived. We assumed the search load of 50 % for case without changing dwell time in fixed frame time and showed the fighter FCR requirement for multi-function is not satisfied because the search load for the uniform search performance should be increased by about 100 %. On the other hand, in case of increasing the frame time for the uniform search performance and search load of 50 %, degradation of the search performance is shown by 86.7 % compared with the former. Based on these analyses, the effective beam operation strategy on an airborne AESA radar with uniform search performance in whole scan area is described with consideration of frame time, search load and performance as a whole.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.7 no.4
• /
• pp.169-178
• /
• 2012

The aim of this study is to look into the influential factors on the care-workers-perceived job stress level according as the elderly-perceived satisfaction varies depending on care workers' organizational characteristic & attitudes toward work, and there's necessity of reducing their job stress. Hereupon, this study, targeting the care workers at domiciliary visit care centers in Seoul district, analyzed the influential factors of organizational factors consisting of the sub-factors, such as job autonomy, compensation, education and development, members' interrelationship, etc. on the perception level of job stress. As a result of analysis, it was found that the shorter their working hours, the more their salary, the more guaranteed their job autonomy, and the better their interrelationship is, the care workers at a domiciliary visit care center had a positive perception of job stress. Accordingly, the operators of domiciliary visit care centers are requested to have a lot more concerns for diverse forms of improvements which can not only improve care workers' working conditions, such as daily working hours and a pay level but also promote a sense of fellowship between members; in addition, it is hoped that the operators should improve the organizational environment so that care workers can freely carry out their assigned business with a sense of responsibility rather than relying on control and regulation.