Search for nn Oscilation in Super-Kamiokande I

장지승,Kenneth S. Ganezer,Jun Kameda 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.2

A search for nn oscilation, a proces of |ΔB| = 2 predicted by L-R symmetric gauge theories, is undertaken using the 24.5×103 neutron-yr exposure of the Super-Kamiokande I. The lifetime's lower limit for neutron bound in oxygen has been determined to be 1.77×1032 yrs at the 90 % confidence level by applying Bayesian statistics to incorporate most major sources of experimental uncertainties. This limit coresponds to the oscilation time for a free neutron, which is calculated to be 2.36×108 s by using a theoretical suppresion factor of 1.0×1023 s-1

국적항공사 외국인 객실승무원의 직무적응 모형 검증에 관한 연구

장지승,이남령,김태준,김승복 한국항공운항학회 2012 한국항공운항학회지 Vol.20 No.3

The number of foreign cabin crews consist of 7% of total crews in K-airline, of which Chinese crews are of 38%. The number of foreign crews are 433 from 10 countries as of the end of July 2012. The airline has continued to hire foreign cabin crews to increase efficiency of human resourcing qualified flight attendants. Thie paper tried to do empirical research through SEM(Structural Equation Model) to overview confirmatory factors and course effects integrally. Cultural stress, aggressive coping, social support and job adaption have been chosen to be a factors. Especially, the SEM was set to show indirect effects of cultural stress and aggressive coping through social support to the dependant variable, job adaptation. According to the analysis result, cultural stress has a direct negative effect on job adaptation. Aggressive coping has also a direct positive effect on job adaptation. It has also proven cultural stress and aggressive coping has a indirect effect to job adaptation through social support. This paper is expect to contribute to develop such training and administrative programs as enhancing foreign crews' job adaptability and managing them effectively.

외국인 승무원의 Self-Leadership이 항공사 조직효과성에 미치는 영향 연구 : 중국인 승무원을 중심으로

장지승,이남령,이근영,김기웅,Jang, Ji-Seung,Lee, Nam-Ryung,Lee, Geun-Young,Kim, Ki-Woong 한국항공운항학회 2015 한국항공운항학회지 Vol.23 No.1

A responsibility of superior management in an airline has become enormous due to rapid increase of airline's organization and its network. Even though a leadership of superior management is believed to be an important factor, it is almost impossible for management to be responsible for all the areas of an airline organization. This is why leadership should be go down to working level people. Self-leadership means that working level people possess leadership, delegated by their superior persons, and improve their work environment with the leadership as well as related right and responsibility. This paper has tried to find out the components of self-leadership perceived by foreign cabin crews and analyzed the impact of self leadership into airline's organizational effectiveness. Based on empirical research results, this paper would suggest administrative and operational implications of managing foreign cabin crews in K-airline. It was found out foreign cabin crews perceive that self reward and self evaluation have a positive impact on self observation factor. The self observation factor has a significant effect on self goal. The self goal is analyzed as a major factor which results in organizational effectiveness.

도암만 수질의 부유물질 농도와 화학적 산소요구량의 시,공간적 특성 및 상관관계

장지승 ( Ji Seong Chang ),장지혜 ( Ji Hye Chang ),조미선 ( Mi Sun Cho ),강형일 ( Hyung Yeel Kahng ),정재성 ( Jae Sung Jung ),안삼영 ( Sam Young Ahn ) 한국환경과학회 2014 한국환경과학회지 Vol.23 No.5

Seasonal and stational variation of SS and COD were investigated from February 2008 to December 2010 and the relationship between them was discussed. During three years monitoring, SS decreased significantly (46% decline) possibly due to the increase of precipitation and thereby resulting salinity drop. COD on average was the highest in 2009. SS was the highest in autumn and the lowest in winter, and over 72% of SS was FSS. While SS is high in the upper sampling stations of the bay with shallow water, COD values do not show any relationship to the geomorphological characteristics. CODins, which was defined as COD after filtration, ranged 56%(winter)~44.6%(summer) and showed no correlation with SS. It indicates that high SS concentration is not necessarily related to the high CODins. The seasonal CODins/SS data, which can be interpreted as COD density in SS, shows that SS in winter contains the dense COD materials compared to the other seasons.

국적항공사 외국인 객실승무원의 직무적응에 관한 실증연구

장지승 ( Ji Seung Jang ),이남령 ( Nam Ryung Lee ),김태준 ( Tae Joon Kim ),김승복 ( Seung Bok Kim ) 한국항공운항학회 2012 한국항공운항학회지 Vol.20 No.3

The number of foreign cabin crews consist of 7% of total crews in K-airline, of which Chinese crews are of 38%. The number of foreign crews are 433 from 10 countries as of the end of July 2012. The airline has continued to hire foreign cabin crews to increase efficiency of human resourcing qualified flight attendants. Thie paper tried to do empirical research through SEM(Structural Equation Model) to overview confirmatory factors and course effects integrally. Cultural stress, aggressive coping, social support and job adaption have been chosen to be a factors. Especially, the SEM was set to show indirect effects of cultural stress and aggressive coping through social support to the dependant variable, job adaptation. According to the analysis result, cultural stress has a direct negative effect on job adaptation. Aggressive coping has also a direct positive effect on job adaptation. It has also proven cultural stress and aggressive coping has a indirect effect to job adaptation through social support. This paper is expect to contribute to develop such training and administrative programs as enhancing foreign crews`` job adaptability and managing them effectively.

RENO 검출기의 검출효율 측정 연구

신창동,장지승 한국물리학회 2012 새물리 Vol.62 No.9

RENO, which is a domestic reactor neutrino experiment to measure the neutrino mixing angle Θ_(13), has been recording data since August 2011. Θ_(13) is measured by observing at the near and the far detectors the disappearance of neutrinos from the reactor. For those measurements, the detection efficiency of the reactor neutrino at each detector is an important value. In this research,we measured the detection efficiency at RENO and calculated the systematic uncertainties. 중성미자 진동 변환상수Θ_(13) 측정을 위한 국내 원전 중성미자실험 RENO가 2011년 8월부터 데이터 획득을 시작하였다. 영광원전으로부터 가까운 거리에 위치한 근거리 검출기와 먼 거리에 위치한원거리 검출기에서 중성미자의 사라짐을 관측함으로써 Θ_(13)를측정할 수 있는데, 이 때 각 검출기에서 원전 중성미자의 검출효율은중요한 상수로 사용된다. 본 논문에서는 몬테카를로를 이용하여 RENO 검출기의 검출효율과 그에 대한 오차를 계산해 보았다.

Data Compression and Transmission Algorithms for CMS FRPC Muon Chambers

최준호,장지승,M.Jeong,J.Y.Kim,S.H.Lim,K.J.Ma,I.T.Lim,I.S.Jeong,M.Y.Pac,장한일,S.B.Kim,S.M.Lee,I.H.Park 한국물리학회 2002 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.41 No.3

The CMS (compact muon solenoid) will have a forward resistive plate chamber (FRPC) to identify muons, measure their transverse momenta, pt, and determine the bunch crossing from which they originate. The trigger algorithm is based on the muon pattern comparator (PACT). The actual hit pattern is compared to a set of predened possible hit patterns for a muon with definite transverse momentum. When a match is found, the muon transverse momentum is determined at the same time. For that, the synchronized bit signals from four layers of the RPCs have to be brought to one processor. A huge interconnection network is needed to fulll this task. To reduce the cost of the links trasmitting data from the detector to the control system, we propose two compression/decompression systems for the data transmission based on both the SPC (segmentposition- compression) method and the RLE (run-length-encoding) method with bunch crossing time information. The ideas for such systems are simulated and discussed.

회전익 항공기의 외부 인양물에 대한 조종사 훈련 활성화 방안 연구 : EASA 및 FAA 사례를 중심으로

황재갑,장지승 한국항행학회 2023 韓國航行學會論文誌 Vol.27 No.3

A main purpose of this research was to analyze environmental factors to influence helicopter accidents contrary to the fact that the almost 80% of helicopter accidents happened due to pilots’ human errors. There have been about 14 helicopter accidents in civil aviation sector last decade. It is noteworthy that nine of 14 accidents happened during the external sling load operation. Moreover, there is no law or regulation which could cover the helicopter external sling load operation or human external cargo in Korea. In this paper, it was analyzed the training and education regulations regarding helicopter external sling load operation or human external cargo in regulations of FAA and EASA, Based on analyzing and comparing the FAR part 133 and domestic aviation law (aviation safety act and flight safety regulations), it was found out the implication how to apply helicopter type rating for external sling load operation and human external cargo operation. To sum up, this paper expect central government should cooperate and amend aviation law which apply external sling load operation and external cargo to establish sound safety culture in Korea. 본 연구는 민간 회전익항공기 사고의 80% 이상이 조종과실이라는 사실과는 대조적으로, 모든 국내 회전익항공기 조종사들은 군에서 많은 경험을 가지고 민간 분야에서 종사한다는 점에서 어떤 특정한 환경적 요인이 있을 것이라는 명제를 바탕으로 연구를 시작하게 되었다. 우리는 지난 10년간 총 14건의 민간 회전익 항공기 사고가 있었다. 그중 9건 (64%)이 항공기 외부에 인양물을 매달은 채로 사고가 발생했다는 사실과 국내 외부인양물에 대한 구체적인 훈련 규정이 없다는 점을 반영하여, 우선 조종사 외부 인양물 훈련에 대한 국내외 훈련 및 자격 부여 과정을 비교 분석하였다. 그리고 조종사 훈련과 관련된 미국 연방항공청 (FAA) 파트 133 규정인 회전익 항공기(헬리콥터)를 이용한 외부화물 운송관련 법률과 국내 법률을 비교 분석하여 시사점을 도출하여 국내 상황을 적합한 외부인양물에 대한 조종사 훈련과 자격부여에 대한 대안을 제시하고자 하였다.

항공여객이 인식하는 편익이 가격신뢰를 매개로 재구매 의도에 미치는 영향 : 인천-두바이 구간 국적항공사와 외국항공사 비교를 중심으로

이근영,김수정,장지승 한국항행학회 2020 韓國航行學會論文誌 Vol.24 No.3

This research focused on such a passenger sample that used to fly between Incheon int’l airport(ICN) and Dubai int’l airport(DXB) using either a national carrier or gulf carriers because the route between ICN and DXB is one of the international air routes with the toughest competition under the global pressure of open air transport market. Based on the results from the empirical research, this paper proposed a competitive advantage which a national carrier must have to cope with global competition under the open sky policies and implications for sustainable strategies of them. National carrier passengers perceived product benefits had a significant positive effect on price reliability in spite of lower price competitiveness. Following the empirical analysis results, it was proven a national carrier should try to improve product benefit sought by passengers to maintain sustainable competitive advantage in the market against foreign airlines. 본 연구는 인천국제공항(ICN)-두바이국제공항(DXB)의 정기 노선을 취항하고 있는 대한민국 국적항공사 및 중동 국적항공사를 이용객들을 연구의 대상으로 하였다. 항공시장의 자유화 압박 속에서 국적항공사 對 외국항공사의 시장 경쟁이 가장 치열한 노선들 중 하나이기 때문이다. 실증연구를 통해 국적항공사의 경쟁적 우위는 무엇이고 향후 시장 자유화 확대 기조에서 치열한 경쟁에서 살아남기 위한 지속가능한 전략이 무엇인지 시사점을 도출하고자 하였다. 인천-두바이 노선에서 국적항공사 이용객들의 우수한 제품 편익에 대한 인식은 가격 프리미엄을 지불하고서라도 재구매 의도에 유의한 영향을 미치는 것으로 판명되었다. 반면 외국항공사 이용객들의 제품 편익은 저렴한 가격과 아무런 상관성이 없는 것으로 분석되었다. 국적 항공사의 제품 편익을 향후 더욱 강화한다면, 동 노선에서 외국 항공사들의 가격 우월성과 경쟁하고 시장에서 경쟁적 우위를 지속적으로 유지할 수 있을 것이다.

정기항공사 소속 조종사의 비행경력에 따른 시계접근능력 차이 분석 : 비모수 통계검정을 포함하여

이근영,황재갑,장지승 한국항행학회 2019 韓國航行學會論文誌 Vol.23 No.2

There are keen competitions among the air operators to recruit competent pilots, which could be adversely affect the safe operation of aircraft. This study is aimed to identify the correlation between the flight experience of the pilot of the air transport operator and competency on visual approach operation. About 2,400 sets of flight training data of several pilots of an air transport operator was analysed for this study. The analysis showed that most captains were able to make stabilized visual approach regardless of his/her flight experience of any type of aircraft, while the first officers were able to make a stabilized visual approach with more than 1,500 hours of flight experience for each rated type of aircraft. This should be considered during making policies for the supply and demand of pilots for the safe operation of air transport. 본 연구는 정기항공사 소속 조종사들을 대상으로 그들의 비행경력과 운항능력에 대한 실증연구를 하였다. 첫째, 정기항공사 소속 조종사들의 비행경력(비행시간 및 기종)에 따른 운항능력의 차이를 분석하였다. 이를 통해 신규로 항공운송용 조종사로 진입하고자 하는 인력들에 대해 항공사가 기대하는 조종사의 운항능력의 수준을 검증할 수 있었다. 분석결과 기장의 경우 해당기종 비행시간이 500시간이든 1500시간이든 시계비행 운항심사 결과 간의 차이가 없는 것으로 나타났다. 부기장은 1,500시간 이상부터는 시계비행 운항심사 결과의 차이가 나타났다. 부기장은 기장과 달리 해당기종 비행시간을 많이 가질수록 안정적인 시계접근을 할 수 있음이 판명된 것이다. 기종특성과 관련하여 cable 또는 fly-by-wire 기종에 따라 기장 집단은 시계비행 운항능력의 차이가 없었다. 즉, 시계접근의 경우는 기종에 관계없이 기장급 조종사의 기량이 평가된다고 할 수 있겠다. 부기장 집단에서는 기종 특성에 따른 유의한 차이가 있는 것으로 판명되었다.