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본 논문에서는 국내에 소재한 한국 물류 기업들의 SCM 구축요인이 기업의 성과에 미치는 영향에 관하여 실증분석을 하였다. 우리나라의 물류 기업들에게 SCM 구축요인의 필요성과 그 이해 정도에 따라 근무자가 기대하는 기업의 성과에 어떠한 영향에 대해 분석을 통하여 우리나라 물류 산업의 선진화와 물류 기업들의 경쟁력을 강화하는 것이 목적이다. 국내 수도권에 소재한 60여 개의 기업에서 근무하는 종사자들에게 총 243부의 데이터를 수집하였으며, 수집된 데이터는 SPSS 26.0와 Amos 26.0을 활용하여 상관관계 분석, 구조방정식 모형 등을 분석하였다. 검증결과 SCM을 구축하는 요인으로 조직역량, 정보기술, 파트너십은 지각된 유용성에 직접적인 영향을 미쳤으며, 지각된 유용성은 종속변수인 기업의 재무적 성과와 비재무적 성과에 직접적인 영향을 미쳤다. 연구의 결과로 향후 SCM을 구축을 고려하는 물류 기업에 실증적인 자료로써 활용될 수 있으며, 지각된 유용성이 기업의 성과에 중요한 매개 요소로써 활용될 수 있다는 것에 시사점이 있다.

Purpose – This study analyzes the effect of the authorized economic operator–mutual recognition arrangement (AEO–MRA) on the performance of Korean exporters and importers. The effect of the import–export companies’ characteristics, such as annual sales, the number of foreign markets, and overseas experience, on the AEO–MRA is deduced; the relationship between this effect and firm performance is analyzed. Design/methodology – An empirical research model was constructed and analyzed using structural equation modeling. The effect of AEO–MRA on logistics and operational performance was derived from the aforementioned characteristics as leading factors of the AEO–MRA. The regulatory influence of cooperation with logistics companies was analyzed in the AEO–MRA effect on logistics performance. Thus, 172 valid samples were obtained from import–export companies certified by the AEO–MRA. Findings – Among the aforementioned characteristics, only “annual sales” has a positive effect on the AEO–MRA, whose effect enhances logistics and operational performances. The AEO–MRA effect did not directly affect operational performance. Owing to the adjustment effect analysis, the AEO–MRA effect and logistics performance relationship is strengthened if the cooperative relationship with the logistics company is higher than a certain level. If this cooperation falls below a certain level, the AEO–MRA effect on logistics performance reduces. Thus, logistics cooperation is an important factor in the AEO–MRA effect and logistics performance relationship. Originality/value – Hinging on the resource-based theory and relational viewpoint, an empirical model that explains the relationship between the AEO–MRA effect and firm performance is established.

본 논문은 반사방지막의 성능을 더 정확히 비교 및 분석하기 위하여 기존 방법과 달리 반사방지막에 수직입사가 아닌 입사각이 $8^{\circ}$ 에서 $60^{\circ}$ 까지 변화한다고 가정하고 단층 구조와 다층 구조의 반사방지막의 평균반사율을 계산하고 비교하였다. 입사파의 파장범위를 400 nm ~ 1200 nm 라고 가정하고, 분석에 사용된 반사방지막의 구조는 두께 180 nm인 1차 및 5차 함수의 굴절률 분포를 갖는 6층 구조와 균일한 굴절률 분포를 갖는 단층구조이다. 분석 결과로써 180 nm 단층구조의 경우 평균반사율이 19.6 % 이고, 같은 두께의 6층 구조의 1차 함수 굴절률 분포에서는 14.2 % 이고, 5차 함수 경우에는 11.6 %의 결과를 얻어 균일한 굴절률 분포의 단층구조 보다 5차 함수 굴절률 분포를 갖는 6층 구조의 경우 약 8%의 반사율 감소 효과를 보았다. 이러한 결과는 향후 광소자 및 광 필터에 적용되는 반사방지막 제작에 용용 될 수 있다고 판단된다. 【This paper compares and calculates more precisely the averaged reflectance of antireflection coating with different structure of single and 6 layer assuming the incident angle of light changing from $8^{\circ}$ to $60^{\circ}$ not like normal incidence as usual case. The reflectivity of AR coating of 6 layers with 180 nm thickness having index profile suggested as linear and quintic function and single layer with same thickness having even index are calculated and compared, when the wavelength of incident light ranges from 400 nm to 1200 nm. As the results the AR coating with 6 layers having quintic(linear) function index profile shows the lower reflectance about 11.6 %(14.6 %) than other index profiles, which is approximately 8 % lower reflectance compared with single layer case(about 19.6 %). This results could be applied for the better antireflection coating design applying to optical devices and filters.】

This paper shows an antireflection coating design skill for utilization the thin-film silicon solar cell in the future. The reflectivity of each index profile previously suggested as linear, cubic and quintic function has been calculated and compared. Each index profile is applied to the antireflection coating consisting of 6 layers with 180nm thickness. Also we suggest the graded index profile and compare it's reflectivity to the linear, cubic and quintic's ones. As a results we find the reflectivity generally decreases as the order goes to higher. However the reflectivity in the graded index profile shows the higher(lower) value than ones in the linear, cubic and quintic especially in the shorter(longer) wavelength range from 500 nm to below 700 nm(above 700 nm to 800 nm). Therefore we find that the graded index profile structure could be applied for the better antireflection coating design scheme especially for optical device and optical filter in the range of from deep red to infrared.

This paper is the research on the heated CWDM optical transmitter for the wavelength compensation at the low temperature. In general, the wavelength deviation of DFB laser is around 0.1 nm/C. The wavelength of DFB laser shifts to longer(shorter) wavelength according to the temperature increase(decrease). Typical CWDM optical communication network has 20 nm channel spacing from reference center wavelength per each channel. There is some limitation problem in the range of operating temperature due to the channel interference. For solving the limited temperature range problem, especially at the low temperature, we use the heater on the DFB laser. As a result, we could realize the CWDM optical transmitter to meet +/-6.5 nm from reference center wavelength in the range of temperature at , which is applicable to the industrial field.

본 논문은 박막 실리콘 태양전지에 적용되는 반사방지 또는 고반사 코팅 기술에 관한 연구이다. 태양광 흡수율을 개선하기 위하여 박막 실리콘 태양전지의 앞면에는 반사를 줄이는 반사방지막 기술이 필요하며, 뒷면에는 반대로 반사를 높이는 고반사 기술이 필요하다. 반사방지막 기술에서 단층의 구조에서는 코팅의 두께에 따라 반사율이 틀려지고, 적절한 범위에서 두께를 제어하면 낮은 반사율을 얻을 수 있다. 대칭형태의 다층의 구조에서는 단층구조에 비해서 넓은 파장대에 걸쳐서 낮은 반사율을 얻을 수 있다. 또한 뒷면에 적용되는 고반사막 기술에서는 높은 굴절율을 갖는 매질과 낮은 굴절율을 갖는 매질을 대칭 구조로 구성하여 계산한 결과 높은 반사율을 얻을 수 있다는 것을 확인하였다. 【This paper presents a reflection coating design scheme in the thin-film silicon solar cell. The antireflection(high reflection) coating skill is needed in the front(back) panel of the thin-film solar cell to improve an efficiency of light absorbing. In the single structure a reflectivity is changed according to the thickness of coating for antireflection scheme and its minimum value can be obtained by controlling thickness of coating. In the symmetric multi layer structure low reflectivity can be obtained in the wide wavelength range. And we also find that high reflectivity can be obtained through multi layer structure, which has alternate layers of high and low material, for high reflection scheme in the back panel.】

This paper is the research on SMSR yield improvement of the optical transceiver using modulated DFB laser. In general, the wavelength of DFB laser optical transceiver are 1310, 1490 and 1550 nm. Usually SMSR in modulated DFB is difficult to improve as low as 30 dB because of high slop efficiency trade off. In modulation condition, we studied SMSR improvement according to adjust bias current, extinction ratio and optical line terminal receiver sensitivity. As our test results, we can found a method how to improve SMSR for optical transceiver for long distance.

A novel all-optical gain-controlled (AOGC) bidirectional amplifier is proposed and demonstrated in a compact structure. The AOGC function using fiber Bragg grating (FBG) pairs controls both directional signals independently, and combinations of optical interleavers and isolators suppress Rayleigh backscattering (RB) noise. The amplifier achieves high and constant gain with a wide dynamic input signal range and low noise figure. The performance does not depend on the input signal conditions, whether static-state or transient signals, or whether there is symmetric or asymmetric data traffic on bidirectional transmission. Transmission comparison experiments between invariable symmetrical and random variable asymmetric bidirectional data traffic verify that the all-optical gain control and bidirectional amplification functions are successfully combined into this proposed amplifier.

A fibre optic technique based on the Fresnel reflection from the fibre tip is used for measurements of the refractive indices of various liquids at wavelengths of 1310 and 1551 nm. Reflection signals from liquid?fibre interface are compared with reflection signals from air?fibre interface to obtain the refractive index. Values of refractive indices for distilled water measured by this technique compare very well with known values at both wavelengths only if the fibre effective waveguide index is used. Applying the double-pulse measurement technique, it is shown that a measurement resolution of about 2.5 ? 10?5 can be achieved.

A new and simple calibration technique that greatly enhances the measurement sensitivity of conventional fiber-optic reflectometry based on Fresnel reflection from the tip of a fiber is used for demonstrating the feasibility of measuring solute concentrations and index changes in fluids to very high precision. The amplitude of pulses originating from reflection from the fiber-fluid interface is compared in real-time with the amplitude of reference pulses from a fiber-air interface such that errors caused by pulse amplitude fluctuations and slightly varying detector responses are corrected. Using solutions of salt and water, it is demonstrated that the technique is capable of measuring index changes of about $1 {\times} 10^{-5}$ corresponding to a salt concentrations of 0.01 %.

We fabricated a-Si:H transparent solar cells with thin absorbers. The light induced degradation of 17 % to 22 % was obtained when 130, 150 and 200 nm thick absorbers were used in the fabrication of a-Si:H transparent solar cells. However, the cells with 108 and 120 nm thick absorber showed improved light induced degradation. In particular, the cell with 108 nm thick absorber showed highly improved degradation of 7.3 %. In this case, the p-layer thickness is crucial to determine the degradation rate.

We present a simple measurement technique of the cross phase modulation in optical fibers. A pump laser generates a new optical component (Stokes wave) in a probe optical wave with the modulation frequency of a pump laser. We investigated optical heterodyning between the probe optical wave and the Stokes wave, which allows one to generate and evaluate a beat signal in the lower frequency range. With the probe optical wave including the Stokes wave, the cross phase modulation signal can be measured in the pump laser modulation frequency to the tens of kHz range.

We systematically compare the transmission performance of three different modulation formats, return-to-zero (RZ), chirped RZ (CRZ) and vestigial sideband RZ (VSRZ) on the economically effective transmission link using standard single mode fiber (SSMF) and all Erbium-doped fiber amplifiers (EDFAs). This link is composed of wavelength division multiplexed (WDM) channels at 10 Gbit/s over 24 times 100 km amplifier spans without using new types of fibers and Raman amplifiers. The generation of each modulation format in experiments is optimized for more reasonable comparison, and their optical characteristics are investigated by comparing with simulation results. Optimum input powers into SSMF and dispersion compensation fiber (DCF) for each modulation format signal were explored and transmission performance was compared. In our cost-effective transmission link, CRZ signal showed the lowest input power and best performance among all the formats investigated.

A low-cost and compact clock recovery module using a newly developed high-Q dielectric resonator filter, which could be integrated easily with other circuit blocks, for a 43 Gb/s optical receiver was designed and evaluated

Our amplifier using an all optical method and a fixed GFF achieved automatic gain flatness through all C-band without any NF degradation, and simultaneously a constant 25 dB gain, while input signals were varied between one channel and forty WDM channels.

Our amplifier using an all optical method and a fixed GFF achieved automatic gain flatness through all C-band without any NF degradation, and simultaneously a constant 25 dB gain, while input signals were varied between one channel and forty WDM channels.

A novel all-optical gain-controlled (AOGC) bidirectional amplifier is proposed and demonstrated in a compact structure. The AOGC function using FBG pairs controls both directional signals independently and combinations of optical interleavers and isolators suppress Rayleigh backscattering (RB) noise. The amplifier achieves high and constant gain with wide dynamic input signal range and low noise figure. The performance does not depend on the input signal conditions, whether static-state or transient signals, or whether symmetric or asymmetric data traffic on bidirectional transmission. Transmission comparison experiments between invariable symmetrical and random variable asymmetric bidirectional data traffic verify that the all-optical gain control and bidirectional amplification functions are successfully combined into this proposed amplifier.

Ring cavity lasers employ an Er doped or a semiconductor gain medium including a wavelength selective element for tuning a lasing wavelength. For a wavelength tuner, a tunable optical filter can be realized using a rotatable grating, Fabry-Perot cavity or an acousto-optic element. In the paper, we demonstrate the fiber ring laser tuned by controlling polarization states along the birefringent optical fiber loop. The ring laser consists of a semiconductor optical amplifier, a polarization controller combined with a rotatable intra-cavity polarizer for a wavelength selective element, and a 9:1 coupler. The ring also includes a polarization independent in-line optical isolator for providing unidirectional operation and an attenuator to adjust a loop loss.

In this paper, a design procedure for photovoltaic/wind hybrid power generation system is presented. The hybrid system is composed of a DC/DC converter for photovoltaic energy conversion, a DC/DC converter for wind energy conversion, a four switch IGBT inverter converting the combined DC power to the AC power and a backup power battery. Here, it is very important to select the desired battery size to meet the stable output and economic cost aspect since this system utilizes a fluctuating and finite energy resource. The purpose of this paper is to develop a sizing method for the PV/wind energy hybrid system with load sharing operation. The method demonstrates a simple tool to determine the desired battery size that satisfies the energy demand from the user with the photovoltaic and wind natural source. The proposed method is verified on a 14 kW hybrid power system including a 10 kW PV generator and a 4 kW wind generator established in Cheju island, Korea.

We present a simple dynamic gain control of a booster amplifier (EDFA-erbium-doped fibre amplifier) with an optical supervisory channel power adjustment in WDM transmission systems. As a result, we performed gain clamping and power clamping of EDFA in the optical link. We can transmit 10 Gbps WDM signals and a 155 Mbps supervisory signal through a single mode fiber 320 km according to the change of signal channel number.

This paper introduces a WDM system structure for protecting systems at optical channel layer and optical multiplexer layer respectively. The maintenance signal operation method for WDM systems is also presented for the case of system failure in comparison to SDH ones.

A receiver configuration using a single shared delay interferometer (DI) for optical differential phase-shift keying (DPSK) wavelength-division multiplexing (WDM) signals is demonstrated and investigated in 40-Gbit/s signal transmission. Experiment comparison between the proposed and conventional configurations is performed for signal performance and a 3-dB bandwidth of the receiver sensitivity penalty. The wavelength mismatch of optical components used and the effects are measured to investigate the wavelength dependency of the proposed configuration. This demonstrates that there is no difference in performance between the two configurations and between WDM channels in the proposed configuration. Thus, it is suggested that the proposed configuration using a single DI can be applied for 20 WDM channels between 1531.116 and 1561.419 nm, with 200-GHz channel spacing in a bandwidth of >30 nm, for receiving DPSK signals.

We demonstrate a capacity upgrade to a 40-Gb/s channel rate with reconfigurable optical add-drop multiplexing ROADM opera- tion from a 3210-Gb/s-based unrepeated WDM link. The 1640-Gb/s channels were added at the ROADM node without traffic interruption in the expressed channels. The worst channel of the 40-Gb/s rate shows 1.1 dB of Q-value margin to the forward error cor- rection FEC limit. The expressed 10-Gb/s channels also satisfy the transmission limit of the bit error ratio BER 10 15 without FEC

We systematically compare the transmission performance of three different modulation formats—return-to-zero (RZ), chirped RZ (CRZ), and vestigial sideband RZ—on an economically possible transmission link using standard single-mode fiber (SSMF) and all erbium-doped fiber amplifiers. This link is composed of wavelength-division multiplexed channels at 10 Gbit/s over 24×100-km amplifier spans without using new types of fibers or Raman amplifiers. The generation of each modulation format in the experiments is optimized for more reasonable comparison, and their optical characteristics are investigated by comparison with simulation results. Optimum input powers into SSMF and dispersion compensation fiber for each modulation format signal were explored, and their transmission performance was compared. In our cost-effective transmission link, the CRZ signal showed the lowest input power and best performance among all the formats investigated.