디지털 측정기로 측정된 급기가압 제연구역의 출입문 개방력에 대한 신뢰성 분석 및 최적 조건 제시

이재오(Lee, Jae-Oh),최충석(Choi, Chung-Seog) 한국산학기술학회 2016 한국산학기술학회논문지 Vol.17 No.1

본 연구는 디지털 측정기(Digital Force Gauge)를 이용해 급기가압 제연구역 출입문의 개방력을 측정하여 신뢰성을 검증하는데 있다. 개방력은 제연구역에 급기가압 기류가 들어가기 전과 후의 개방 부하를 측정하였다. 측정값은 미니탭 프로 그램(Minitab PGM)의 AD(Anderson Darling) 통계분석법으로 신뢰도를 검증하였다. 분석된 P값은 제연설비의 작동 전과 후 의 일부 층을 제외하고는 0.05 이상을 나타낸 것으로 보아 95% 신뢰도가 있는 것으로 해석된다. 측정값의 정규분포는 제연설 비의 작동 여부와 관계가 없었으며, 계측기의 정밀도는 신뢰할 수 있는 것으로 분석된다. 그리고 급기가압 제연설비의 최적 설계 조건은 계측기의 정밀도와 신뢰성, 측정자의 바른 자세, 출입문의 동일한 조건 등이 주요 인자로 판단된다. 따라서 급기 가압 제연구역 출입문의 개방력의 측정은 디지털 측정기가 적합한 것으로 판단된다. 또한 효과적인 개방력의 측정은 측정자 의 자세 표준화, 출입문의 초기 개방력의 설정 등이 주요 변수로 작용하고 있음을 알 수 있었다. The aim of this study was to measure the opening force of an access door of a pressurized smoke control zone and verify the reliability of the opening force. For the access door opening force, the opening load of the access door was measured before and after pressurized air had entered the smoke control zone. The reliability of the measured values was verified using the Anderson Darling's statistical analysis method of the Minitab Program. Because the analyzed P values were greater than 0.05 except for some floors before and after the operation of the smoke control equipment, the opening force was found to have 95% reliability. The normal distribution of the measured values showed no relationship with the operation of the smoke control equipment and the precision of the force gauge was believed to be reliable. The major factors for the optimal design of the pressurized smoke control equipment include the precision and reliability of the force gauge, the correct posture of the measuring person, and the same conditions for access doors. Therefore, a digital force gauge is believed to be suitable for measuring the opening force of the access door of a pressurized smoke control zone. In addition, standardization of the posture of a measuring person, the setup of the initial opening force of an access door, etc., are major variables for effective measurements of the door opening force of an access door.

PMLSM의 SKew 와 Overhang 효과에 대한 3D 유한 요소 해석

李東燁(Dong-Yeup Lee),黃寅喆(In-Cheol Hwang),姜圭洪(Gyu-Hong Kang),金奎卓(Gyu-Tak Kim) 대한전기학회 2006 전기학회논문지 B Vol.55 No.10

This paper deals with skew and overhang effects of permanent magnet linear synchronous motor(PMLSM). The detent force and thrust characteristics considering skew and overhang effects of permanent magnet are analyzed by 3D finite element method and the results are compared to experimental values. As skew and overhang are applied to permanent magnet, the thrust is almost the same value but the detent force is reduced remarkably. By harmonic analysis, the distortion ratio of thrust is remarkably reduced from 4.29[%] to 2.3[%]. and. the ripple ratio of thrust is decreased from 8.2[%] to 3.56[%] at the same time. But, the lateral force which operate as the perpendicular direction of skew direction is generated. The lateral force and normal force acts by braking force between mover and LM-guide. Therefore. normal force and lateral force's reduction is required for more efficient drivinz of PMLSM.

Unbalanced Magnetic Forces in Rotational Unsymmetrical Transverse Flux Machine

Salwa Baserrah,Keno Rixen,Bernd Orlik 대한전기학회 2012 Journal of Electrical Engineering & Technology Vol.7 No.2

The torque and unbalanced magnetic forces in permanent magnet machines are resultants of the tangential, axial and normal magnetic forces, respectively. Those are in general influenced by pole-teeth-winding configuration. A study of the torque and unbalanced magnetic forces of a small flux concentrating permanent magnet transverse flux machine (FCPM-TFM) in segmented compact structure is presented in this paper. By using FLUX3D software from Cedrat, Maxwell stress tensor has been solved. Finite element (FE-) magneto static study followed by transient analysis has been conducted to investigate the influence of unsymmetrical winding pattern, in respect to the rotor, on the performance of the FCPM-TFM. Calculating the magnetic field components in the air gap has required an introduction of a 2D grid in the middle of the air gap, whereby good estimations of the forces are obtained. In this machine, the axial magnetic forces reveal relatively higher amplitudes compared to the normal forces. Practical results of a prototype motor are demonstrated through the analysis.

Unbalanced Magnetic Forces in Rotational Unsymmetrical Transverse Flux Machine

Baserrah, Salwa,Rixen, Keno,Orlik, Bernd The Korean Institute of Electrical Engineers 2012 Journal of Electrical Engineering & Technology Vol.7 No.2

The torque and unbalanced magnetic forces in permanent magnet machines are resultants of the tangential, axial and normal magnetic forces, respectively. Those are in general influenced by pole-teeth-winding configuration. A study of the torque and unbalanced magnetic forces of a small flux concentrating permanent magnet transverse flux machine (FCPM-TFM) in segmented compact structure is presented in this paper. By using FLUX3D software from Cedrat, Maxwell stress tensor has been solved. Finite element (FE-) magneto static study followed by transient analysis has been conducted to investigate the influence of unsymmetrical winding pattern, in respect to the rotor, on the performance of the FCPM-TFM. Calculating the magnetic field components in the air gap has required an introduction of a 2D grid in the middle of the air gap, whereby good estimations of the forces are obtained. In this machine, the axial magnetic forces reveal relatively higher amplitudes compared to the normal forces. Practical results of a prototype motor are demonstrated through the analysis.

Effects on Normal Force and Input Voltage Variation in the Resonance Characteristics of an Ultrasonic Motor

Oh, Jin-Heon,Lim, Jong-Nam,Lee, Seung-Su The Korean Institute of Electrical and Electronic 2009 Transactions on Electrical and Electronic Material Vol.10 No.5

In an ultrasonic motor, a piezoelectric ceramic material forms the active element which vibrates the stator, thus initiating the rotational motion. In the operation of ultrasonic motors, many factors exist that can affect the resonance characteristics of the piezoelectric ceramic component. For examples, these factors are the bonding conditions with the piezoelectric element, the magnitude of the input voltage, the normal force in the frictional drive and the emission of heat due to vibration and friction etc. Therefore, it is important to research properly the inclination for variation of piezoelectric ceramics in the circumstance where complex elements are involved. In this paper, we focus on the analysis of the resonance characteristics of an ultrasonic motor as a function of the magnitude of the input voltage and the normal force.

Effects on Normal Force and Input Voltage Variation in the Resonance Characteristics of an Ultrasonic Motor

오진헌,임종남,이승수 한국전기전자재료학회 2009 Transactions on Electrical and Electronic Material Vol.10 No.5

In an ultrasonic motor, a piezoelectric ceramic material forms the active element which vibrates the stator, thus initiating the rotational motion. In the operation of ultrasonic motors, many factors exist that can affect the resonance characteristics of the piezoelectric ceramic component. For examples, these factors are the bonding conditions with the piezoelectric element, the magnitude of the input voltage, the normal force in the frictional drive and the emission of heat due to vibration and friction etc. Therefore, it is important to research properly the inclination for variation of piezoelectric ceramics in the circumstance where complex elements are involved. In this paper, we focus on the analysis of the resonance characteristics of an ultrasonic motor as a function of the magnitude of the input voltage and the normal force.

자기부상 추진용 선형 유도전동기의 수직력 최소화 설계

김미정(Mijung Kim),김원호(Wonhok Kim),장익상(Iksang Jang),이기덕(Kidoek Lee),한정호(Jungho Han),이주(Ju Lee) 한국자동차공학회 2011 한국자동차공학회 부문종합 학술대회 Vol.2011 No.5

In recent years, the induction motor (SLIM) has become the most suitable choice for propel system of magnetic levitation. Although LIMs have certain special characteristics, because of the non-continuity of the magnetic field in LIMs, they encounter some magnetic problems, which do not exist in rotational-type motors. Longitudinal end effect and edge effect are two major electromagnetic phenomena, which make the analysis and design of these motors difficult. So far, different analysis methods to model LIMs have been outlined. Moreover, the normal force significantly affects the behavior of the device and the system to which it is attached. This normal force can attract the mover to, or repel the mover from, the primary. The magnitude and direction of this force are highly dependent on the motor speed and the terminal conditions. This paper proposes a method for the minimization of the normal force.

이사부 해양정신과 리더십

정진술 한국이사부학회 2014 이사부와 동해 Vol.8 No.-

The naval force of Shilla has been gradually fortified during the defense against Japanese invasion and Isabu conquered Usanguk at the beginning of 6th century by leading the fortified naval force of Shilla. The battleships of Isabu left the port of Samcheok in the afternoon and went towards Ulleungdo Island following the normal direction ocean navigation, which was safe ocean navigation in the primitive ocean navigation ages.The first aspect of maritime spirit of Isabu is the adventurous challenge spirit. The reason why young people of Shilla were not afraid of going out to the ocean is based on the navigation leading to conquest of Usanguk by Isabu, which was an adventure that needed a very special courage at that time. The second aspect of Isabu's maritime spirit is the pioneer spirit. Shilla developed rapidly during the reign of King Jijeung, Beopheung, Jinheung in the 6th century, annexed Usanguk with Gaya, and gained control of Hangang River basin. Isabu played the central role in this territorial expansion. The third aspect of Isabu's maritime spirit is the spirit of great commander of the ocean. The great commanders of the ocean who had an important influence on the direction of development of our country's history include Yi Sun-Shin, Jang Bogo and Isabu. Isabu can be the first great commander of the ocean in our country. The first aspect of Isabu's leadership is establishment of the base of Shilla's naval force. The naval force of Shilla strengthened its base during Usanguk conquest, and repeated its development to demonstrate its ability during the battles that led to the unification of Three Kingdoms. The second aspect of Isabu's leadership is management of state based on "Chuljangipsang", which means that one becomes a general in battleground, and the prime minister in Royal Court. Isabu, who was good at both literary and military arts, laid the foundation of Shilla development through "Chuljangipsang" spirit during more than 60 years of service. 신라 수군은 왜의 침입에 대한 방어과정에서 점차 강화되었고, 이사부는 강화된 신라 수군을 거느리고 6세기 초에 우산국을 정벌하였다. 이사부의 전선들은 삼척포구를 오후에 출항하여 원시항해술시대의 안전한 대양항해술인 정방향 대양항해술에 따라 울릉도로 향했다. 이사부 해양정신의 첫째는 해양 진취적 도전정신이다. 신라 청년들이 바다로 나가는 것을 두려워하지 않았던 배경에는 이사부의 우산국 정벌 항해가 있었다. 우산국 정벌 항해는 당시로서는 모험이었고 매우 특별한 용기를 필요로 했다. 이사부 해양정신의 둘째는 선구적 영토 개척정신이다. 신라는 6세기 지증٠법흥٠진흥왕 때에 비약적으로 성장하여 우산국과 가야를 병합하고 한강 유역을 장악했다. 이사부는 이러한 영토 확장의 중심에서 활약했다. 이사부 해양정신의 셋째는 계보를 잇는 수군 명장의 정신이다. 우리나라 역사의 전개방향에 큰 영향을 끼쳤던 수군 명장은 이순신, 왕건, 장보고, 이사부라 할 수있다. 이사부는 우리나라 최초의 수군 명장으로 자리매김 될 수 있다. 이사부 리더십의 첫째는 신라 수군의 기반 구축이다. 신라 수군은 이사부의 우산국 정벌작전에서 그 기반이 다져지고, 이후 발전을 거듭해 삼국통일전쟁기에 그 실력이 크게 발휘되었다. 이사부 리더십의 둘째는 출장입상의 국가운영 리더십이다. 출장입상은 전쟁터에 나가면 장수로, 조정에 들어오면 재상으로 활약한다는 뜻이다. 이사부는 문무를 겸전한 인물로 60여 년간 관직에 있으면서 출장입상하며 신라 발전의 초석을 쌓았다.

일본은 보통국가인가?: 군사력 수준과 무력행사 범위의 고찰

김태효(Tae-Hyo Kim),박중현(Joong-Hyeon Park) 고려대학교 일민국제관계연구원 2020 국제관계연구 Vol.25 No.2

이 논문은 아베 재집권기 내각 때 이루어진 일본 안보정책의 확장 범위가 그 이전에 비해 얼마나 크고 어떻게 다른지 학술적으로 분석한다. 이를 위해 그동안 일본 안보 담론에서 제기돼 온 ‘보통국가론’의 개념을 재정립하고 현재의 일본이 과연 보통국가의 기준을 충족하는지 여부를 검증한다. 보통국가의 판별 기준으로 ① 원거리 공격능력과 ② 무력행사 범위 두 가지 기준을 제시한다. 일본의 원거리 공격능력은 무기체계의 변화와 국제훈련 참가 현황을 통해 평가하며, 무력행사 가능범위는 일본의 해외파병과 무기사용을 가능케 하는 조건을 살펴 평가할 것이다. 이어서 미일동맹과 평화헌법의 지속성 여부를 평가하고 전망하여 일본 안보정책의 확장 가능 범위를 검토한다. 결론적으로, 첫 번째 기준인 군사력은 보통국가 수준에 도달했거나 혹은 이에 매우 근접하지만, 두 번째 기준인 무력행사 가능범위에는 아직 제약이 있으며, 일본이 처한 대내외 안보환경을 고려할 때 일본이 보통국가에 도달하기는 당분간 쉽지 않음을 주장한다. This paper analyzes the expansion of Japan’s security policy during the Abe era and the impact of that transformation. The authors redefine the concept of “normal state” and examine whether Japan is a “normal state.” We present two criteria for determining whether a country is “normal” in terms of its security policy: possession of long-range attack capability and the way it uses its forces. Japan’s long-range attack capability is assessed through changes in weapons system and the form of its participation in international military exercises. The scope of its possible armed activities is assessed by looking at conditions that Japan uses to decide whether to send troops abroad and use weapons. The paper then evaluates the scope of Japan’s security policy expansion by assessing and predicting whether the US-Japan alliance and the Peace Constitution are sustainable. We conclude that the first criterion, military power, has reached or is very close to the level of a “normal state,” but the second criterion, the range of possible armed activities, remains limited. The paper argues that Japan will not become a “normal state” for the time being, given the internal and external security environment it faces.

Fractional effect in an orthotropic magneto-thermoelastic rotating solid of type GN-II due to normal force

Parveen Lata,Himanshi 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.81 No.4

In this article, we have examined the effect of fractional order parameter in a two-dimensional orthotropic magnetothermoelastic solid in generalized thermoelasticity without energy dissipation with fractional order heat transfer in the context of hall current, rotation and two-temperature due to normal force. Laplace and Fourier transform techniques are used to obtain the solution of the problem. The expressions for displacement components, stress components, current density components and conductive temperature are obtained in transformed domain and then in physical domain by using numerical inversion method. The effect of fractional parameter on all the components has been depicted through graphs. Some special cases are also discussed in the present investigation.