Broad-Band Amplifiers Using Shunt Resistive Loading Technique

Ki-Jae Song(송기재),Jong-Chul Lee(이종철) 한국통신학회 1999 한국통신학회 학술대회논문집 Vol.1999 No.7

홍삼과 갈조류 혼합 음료 섭취 전후의 체조 선수 유연성 변화

송기재 ( Ki-jae Song ),오재근 ( Jae-keun Oh ) 한국체육대학교 체육과학연구소 2017 스포츠사이언스 Vol.34 No.2

This study aims to identify the effects of one time intake of red ginseng and Phaeophyceae mixed drink on the improvement of shoulder joint and trunk flexibility in gymnasts, and to provide basic data on prevention of injury and improvement of performance. For this purpose, total 19 elite gymnasts from K university in Seoul participated and they were divided into 10 persons of EXP(intake) group and 9 persons of CON(no intake) group. Pre-measurement was performed height using, body composition analysis, trunk flexibility and shoulder joints flexibility. After 1 hour rest period after pre-measurement, post-measurement was performed in the same manner as the pre-measurement. In the case of intake group, red ginseng and brown algae mixed drink was consumed 30 minutes before post-measurement. One-way repeated measure ANOVA was performed to compare the difference in trunk and shoulder flexibility according to the presence or absence of intake between two the groups. The significance level of the statistical significance was set as α=.05. The flexibility of the trunk and left & right shoulder according to the presence or absence of ingestion showed no statistically significant difference between the groups in pre-measurement(p=.744, p=.891, p=.758) and post-measurement(p=.143, p=.455, p=.670). In the times within the group, there was a statistically significant difference in trunk and left and right shoulder flexibility only in the EXP group(p=.001, p=.007, p=.008). There was s statistically significant difference only in the trunk and left shoulder flexibility in group and time interaction(p=.001, p=043). These results suggest that gymnasts flexibility and shoulder flexibility are improved during one-time intake of red ginseng and brown algae mixed drink, which will have a positive effect on prevention of sports injury and improvement of performance.

항공포워더의 항공사 선택요인 및 선택대안에 관한 연구 -중단거리노선에서 소형화물을 중심으로-

송기재 ( Ki Jae Song ),김태복 ( Tae Bok Kim ) 한국항공경영학회 2015 한국항공경영학회지 Vol.13 No.6

국적 저비용항공사들이 2012년에 국제선 화물운송사업을 시작한 이래 이들이 운송한 소형화물의 항공운송물량이 크게 증가하였고, 우리나라의 항공운송시장에서 운송건수측면에서 소형화물운송의 점유율이 매우 높으나, 국적 저비용항공사들의 수출화물의 공급스페이스 이용률은 아직 낮은 수준이다. 따라서, 본 논문에서는 중단거리노선에서 소형화물의 수출운송 시 항공포워더의 항공사 선택요인으로 어떤 것들이 선호되는지와, 그 선택대안으로 국적 저비용항공사와 대형항공사 중 어느 쪽이 더 선호되는지를 파악하고,그들의 경쟁력 제고를 위한 시사점 도출을 위해 연구를 진행하였다.본 연구에서는 AHP기법을 이용한 연구모형을 설정하고, 이메일을 통한 설문조사를 실시하였다. 분석결과 에 따르면, 소형화물의 경우에도 전체화물과 전체노선을 대상으로 한 선행연구에서와 같이, 항공사 선택요인은 비용요인이 가장 높은 중요도를 보였고, 그 다음은 운송특성요인, 서비스특성요인의 순으로 나타났다. 또한, 항공사 선택대안은 대형항공사가 종합적인 선호도측면에서 국적 저비용항공사보다 약간 앞선 것으로 파악되었다. 선택요인별로 보면, 대형항공사는 운송특성과 서비스특성 측면에서 국적 저비용항공사보다 선호도가 앞섰으나, 비용측면에서는 국적 저비용항공사에 뒤진 것으로 나타났다. 국적 저비용항공사들은 운송스케쥴의 신뢰성과 인센티브제도의 개선을 통해 경쟁력을 높일 수 있으며, 대형항공사들은 소형화물에 대해 운송요율을 저렴하게 함으로써 더 나은 경쟁력을 가질 수 있는 것으로 시사되었다. 본 연구의 주된 차별성은 중단거리노선에서의 소형화물에 국한하여 항공포워더의 항공사 선택요인에 대한 분석을 했고, 선택대안을 추가하여 분석의 범위를 확대했으며, 항공사들의 경쟁력 제고를 위한 실무적 시사점을 제공했다는 점에 있다. Since Korean national flag LCCs(low cost carriers) started their international cargo transport in 2012, their transport volumes of small cargoes have increased significantly. However, the utilization rate of their supplied space for export cargoes is still quite lower than expected. And the portion of small cargoes in Korean air transport market is noticeably high. Thus this study is designed to find out which airline choice factors are preferred in the export transport of small cargoes in short-and mid-haul routes, and which out of FSCs(full service carriers) and Korean LCCs as alternatives is preferred, In addition, we try to get implications for improving the competitiveness of the FSCs and Korean LCCs. The research model is based on the AHP method and the survey is conducted by email. The survey results show that even for the small cargoes the Cost factor is the highest in the weight level among the airline choice factors, and then followed by the Transport Characteristics factor and the Service Characteristics factor, which is in an existing study on whole cargoes and whole routes, and that the FSCs exceed the Korean LCCs in the synthesized priority. The survey results also show that the FSCs’ priority exceeds the Korean LCCs in the factors of Transport Characteristics and Service Characteristics, but falls behind the LCCs in the Cost factor. It is implied that the Korean LCCs can enhance their competitiveness by improving the reliability in transport schedule and the incentive system, and that the FSCs can have better competitiveness by lowering their rates for small cargoes. The main differences of this study from the existing studies are that the analysis target for the airline choice factors of air freight forwarders is limited to the small cargoes in short-and mid-haul routes, that the choice alternatives are also analyzed in addition to the choice factors, and that it provides empirical implications for improving the competitiveness of the airlines.

622km 울트라 마라톤 주자의 운동중독 성향 분석

오재근 ( Jae-keun Oh ),박순철 ( Shun-zhe Piao ),박다운 ( Da-woon Park ),송기재 ( Ki-jae Song ) 한국체육대학교 체육과학연구소 2017 스포츠사이언스 Vol.34 No.2

The study was to observed the exercise addiction and the psychological condition of participants(N=50) in the 622 marathon event, which belonged to Korea Ultra Marathon Federation. The questionnaire consists of withdrawal, conflict, attachment, tolerance, and compulsiveness and total 18 questions. The survey results were divided into age, experience, frequency, and time, and T-tested using by windows SPSS PC 21.0 statistics analysis program.. The results are as follows. 1. There was no significant difference in the amount of withdrawal, conflict, attachment, tolerance and compulsiveness and all factors caused by age. 2. There was no significant difference in the amount of withdrawal, conflict, attachment, tolerance and compulsiveness and all factors caused by athletic career. 3. There were no significant differences in the amount of withdrawal, conflict, tolerance and compulsiveness caused by exercise frequency. However, the attachment of participated in the attendance of four or more, and the difference in the number of participants was greater than 4 times(p =.011). 4. There was no significant difference in the amount of exclusion, conflict, attachment, tolerance and compulsiveness and all factors caused by exercise time.

감태(甘苔)에서 추출한 Dieckol 성분이 쥐의 인지능력에 미치는 영향

오재근 ( Jae Keun Oh ),송기재 ( Ki Jae Song ),지무엽 ( Mu Yeop Ji ),윤진호 ( Jin Ho Yoon ) 대한본초학회 2014 大韓本草學會誌 Vol.29 No.6

Objectives : The purpose of this study aimed to investigate that dieckol - isolated from Ecklonia cava - supplementation can improve cognitive ability in mice. Methods : 48-male mice(6 weeks old) were divided into four groups; High-Dieckol group(n=12), Low-Dieckol group(n=12), Placebo group(n=12), Control group(n=12) and they were administered orally 5 days per week for 4 weeks at the same time. We performed Morris water maze test, Passive avoidance test, Blood serotonin analysis. And there was examined on neurogenesis in dentate gyrus of hippocampus using 5-bromo-2`-deoxyuridine (BrdU) to label proliferating cells. Results : The results are as follows; As a Morris water maze results, Trial duration was significantly decreased in high dieckol group comparing to placebo group and control group. Distance to target was significantly decreased in high dieckol group and low dieckol group comparing to placebo group and control group. Mean speed was significantly low in high dieckol group comparing to low dieckol group, placebo group and control group. As a Passive avoidance test results, latency time was significantly long in high dieckol group comparing to low dieckol group, placebo group and control group. BrdU cell count was significantly high in high dieckol group comparing to low dieckol group, placebo group and control group. Conclusions : As a conclusion, it is considered that dieckol supplementation might improve learning and cognitive ability.

후두외상 후 발생한 저음발성 여자환자에서의 라디오전파를 이용한 음도상승 유도 치료 1예

김민호,송기재,최홍식,Kim, Min-Ho,Song, Ki-Jae,Choi, Hong-Shik 대한후두음성언어의학회 2006 대한후두음성언어의학회지 Vol.17 No.1

The factors involved in controlling the vocal pitch are the tension, the mass, the length of the vocal cords and the subglottic pressure. Vocal pitch can be elevated surgically by increasing the stiffness or reducing the vibrating mass of the vocal cords. Recently, we experienced a case of 25 year-old female whose vocal pitch was elevated with radiofrequency surgery of right vocal cord on suspension laryngoscopy. Elevation of vocal pitch(134.11 to 144.73) was noted two months after operation. So we report this case with review of literature.

Effect of a 12-week Shoulder Stability Rehabilitation Program on the Range of Motion and Muscle Strength of Baseball Players with Shoulder Instability

윤진호,오재근,송기재,Yoon, Jin-Ho,Oh, Jae-Keun,Song, Ki-Jae Korea Convergence Society 2021 한국융합학회논문지 Vol.12 No.10

이 연구는 12주간 재활 운동프로그램이 어깨 불안정성을 가진 고등학교 야구선수들의 관절가동범위와 근력에 미치는 효과를 알아보기 위해 실시하였다. 어깨 불안정성이 있는 것으로 판명된 재활 운동군 12명과 정상 운동군 13명을 선정하였다. 12주간 재활운동 참가 전·후 내·외회전 관절가동범위는 공변량분석(ANCOVA)을 실시하였으며, 등속성 근력은 이원변량 분석(two-way ANOVA)을 실시하였으며, 통계적 유의수준은 p<.05로 설정 하였다. 관절가동범위는 불안정이 있는 우위측과 비-우위측 어깨의 경우 재활운동 전·후 내회전 ROM이 유의하게 증가했으며, Total ROM의 경우 불안정이 있는 우위측 어깨에서 재활운동 후 유의하게 증가했다. 등속성 근력의 경우 재활운동 후 내회전 근력이 각속도 180°/sec에서 유의하게 개선되었다. 본 연구 결과를 요약하면 12주간 재활운동 프로그램이 어깨 불안정성 환자의 ROM, 근력 개선에 효과적인 것으로 나타났다. 하지만 제한적 결과에 미루어 재활기간의 연장을 전제로 한 추가적 연구가 필요할 것으로 생각된다. This study investigated the effect of a 12-week rehabilitation program on the range of motion (ROM) and muscle strength of high school baseball players with shoulder instability. We allocated 12 players with shoulder instability to the rehabilitation group and 13 players without shoulder instability to the normal exercise group. Covariate analysis (ANCOVA) was performed to assess the ROM of the internal (IR) and external (ER) rotational joints before and after participating in the 12 weeks of rehabilitation, and two-way ANOVA was performed to assess isokinetic muscle strength. The statistical significance level was set at p<.05. The IR ROM of the dominant (D) shoulder with instability and non-dominant (ND) shoulder was significantly increased before and after the rehabilitation program. The total ROM of the D shoulder with instability significantly increased after rehabilitation. IR isokinetic strength significantly improved at an angular velocity of 180°/s after rehabilitation. These results indicate that the rehabilitation program used in this study could be effective in improving ROM and muscle strength in patients with shoulder instability. However, due to the limited results, additional research on the premise of extending the rehabilitation period is necessary.

유전체 손실을 고려한 전원부에서 유기되는 노이즈 모델링에 관한 연구

김종민(Jongmin Kim),남기훈(Ki-Hoon Nam),하정래(Jungrae Ha),송기재(Ki-Jae Song),나완수(Wansoo Nah) 한국전자파학회 2010 한국전자파학회논문지 Vol.21 No.2

본 논문에서는 전원부에서 노이즈가 발생되어 신호선에 노이즈가 유기될 때, 유전체의 손실 특성이 노이즈에 미치는 영향에 관해서 연구를 하였다. 이를 분석하기 위해 Full-wave 시뮬레이터인 Ansoft사의 HFSS(High Frequency Structure Simulation)와 CST사의 MWS(MicroWave Studio)의 계산 결과와 측정 결과를 비교하여 신뢰성을 확보하였고, 실제 사용되고 있는 4가지의 상용 기판에 대한 유기되는 노이즈를 해석하였다. 또한, TLM(Transmission Line Method)를 이용해서 전원면의 회로 모델 구성 시 기판의 유전체 손실을 반영할 수 있는 Debye 모델을 적용하여 주파수에 대한 임피던스를 분석할 수 있는 모델을 적용 측정 결과와 3 GHz까지 일치하는 모델을 얻었다. In this paper, we propose the modeling of the power/ground plane which includes complex dielectric permittivity and loss tangent for the power/ground coupled noise. In order to estimate the effects of the dielectric substrate for the coupled noise, we used full-wave simulators, HFSS(High Frequency Structure Simulation) and MWS(MicroWave Studio). The simulated results for the commercial substrates are compared with the measured values. TLM(Transmission Line Method) was used for the calculation of power plane impedance using Debye model which depicts the dielectric loss of PCB. Finally, impedance from proposed circuit model showed very good coincidence to the measured data.

임대전용산업단지에 관한 연구

김인중(Kim, In Chung),송기재(Song, Ki Jae) 한국부동산학회 2010 不動産學報 Vol.40 No.-

1. CONTENTS (1) RESEARCH OBJECTIVES The purpose of this study is to suggest the desirable policy direction for the industrial complex specified for lease . (2) RESEARCH METHOD documentary survey, field study, interview, statistical analysis (3) RESEARCH FINDINGS The fundamental policy directions of the industrial complex specified for lease should be ① public owned, ② long-term (more than fifty years), ③ low-cost (1% lease charge out of construction cost). This study points out that Korea Land Corporation can not sustain low-cost and long-term lease industrial complex due to their financial status. Thus these leased have to be sold or government has to provide subsidy to preserve the korea Land Corporation's deficit. Above mentioned three fundamental policy directions start from the recognition that the industrial complex specified for lease seeks public goal and interest. 2. RESULTS To keep UP long-term, low-cost industrial complex specified for lease, government support and allocation of proper budget is cardinal

12주간 수중 밴드 운동프로그램 참여가 여성 노인의 근력, 유연성, 우울감에 미치는 영향

노진아(No, Jin-A),오재근(Oh, Jae-Keun),지무엽(Ji Mu-yeop),윤진호(Yoon, Jin-ho),송기재(Song, Ki-jae) 한국사회체육학회 2021 한국사회체육학회지 Vol.- No.84

Purpose: This study is conducted to identify the effects of underwater resistance exercise using elastic bands on muscle strength, flexibility, and psychological depression in elderly women. Method: The subjects of the study were divided into aquatic band exercise group (n=8), aquatic exercise group (n=8), and control group (n=8). Muscle strength, flexibility, and psychological depression were measured according to participation in exercise for 12 weeks. The difference between groups was identified through the analysis of repeated measured one-way ANOVA, and the post-hoc was using LSD. Results: The results are as follows. 1. Aquatic band exercise group showed a significant difference in muscle strength at the peak torque and total work of 90°/sec knee joint flexion compared to the aquatic exercise group and control group. 2. Aquatic band exercise group showed a significant difference inflexibility compared to the aquatic exercise group and control group. 3. Aquatic band exercise group showed a significant difference in psychological depression compared to the aquatic exercise group and control group. Conclusion: In summary, Aquatic band exercises are effective in improving the muscle strength and flexibility of the elderly woman. Psychological depression is also reduced, which was found to be effective in improving the quality of life.