• 한국광물학회지
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• 제11권2호
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• pp.106-116
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• 1998

The adsorption of Cs-137 and Sr-90 onto kaolinite in prescence of major groundwater cations (Ca2+, K+, Na+) with different concentrations was simulated by using triple-layer surface complexation model (TL-SCM). The site density (8.73 sites/nm2) of kaolinite used for TL-SCM was calculated from it's CEC and specific surface area. TL-SCM modeling results indicate that concentrations dependence on 137Cs and 90Sr adsorption onto kaolinite as a function of pH is best modeled as an outer-sphere surface reaction. This suggests that Cs+ and Sr2+ are adsorbed at the $\beta$-layer in kaolinite-water interface where the electrolytes, Nacl, KCl and CaCl2, bind. However, TL-SCM results on Sr adsorption show a discrepancy between batch data and fitting data in alkaline condition. This may be due to precipitation of SrCO3 and complexation such as SrOH+. Intrinsic reaction constants of ions obtained from model fit are as follows: Kintcs=10-2.10, KintSr=10-2.30, KintK=10-2.80, KintCa=10-3.10 and KintNa=10-3.32. The results are in the agreement with competition order among groundwater ions (K+>Ca2+>Na+) and sorption reference of nuclides (Cs-137>Sr-90) at kaolinite-water interface showed in batch test.

• 한국수산과학회지
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• 제55권2호
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• pp.207-217
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• 2022

The accurate calibration of broadband echo sounders is essential for providing high quality acoustic information for fisheries applications. The increased range resolution of broadband echo sounder systems improves the detection and characterization of targets near boundaries, such as fish near the seabed. Most echo sounder systems are calibrated using tungsten-carbide (WC) spheres. For accurate calibration, it is necessary to select WC spheres of optimized diameters used frequently to calibrate echo sounder systems. For these purposes, the measured and simulated target strength (TS) data for seven WC spheres of different sizes were compared across a bandwidth of 100-200 kHz. The frequency-dependent TS pattern for the specular wave measured from two WC spheres using the fractional Fourier transform was also estimated and analyzed. Comparative results are presented for all the spheres and the best average precision of 0.15 dB was obtained for the 22 mm WC sphere.

• International Journal of Computer Science & Network Security
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• 제21권9호
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• pp.332-338
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• 2021

Civil aviation cybersecurity challenges are global in nature and must be addressed using global best practices and the combined efforts of all stakeholders. This requires the development of comprehensive international strategies and detailed plans for their implementation, with appropriate resources. It is important to build such strategies on a common methodology that can be applied to civil aviation and other interrelated critical infrastructure sectors. The goal of the study was to determine the methodological basis for developing an international civil aviation cybersecurity strategy, taking into account existing experience in strategic planning at the level of international specialized organizations. The research was conducted using general scientific and theoretical research methods: observation, description, formalization, analysis, synthesis, generalization, explanation As a result of the study, it was established the specifics of the approach to formulating strategic goals in civil aviation cybersecurity programs in the documents of intergovernmental and international non-governmental organizations in the aviation sphere, generally based on a comprehensive vision of cybersecurity management. A comparative analysis of strategic priorities, objectives, and planned activities for their implementation revealed common characteristics based on a single methodological sense of cybersecurity as a symbiosis of five components: human capacity, processes, technologies, communications, and its regulatory support. It was found that additional branching and detailing of priority areas in the strategic documents of international civil aviation organizations (by the example of Cybersecurity Strategy and Cybersecurity Action Plan) does not always contribute to compliance with a unified methodological framework. It is argued that to develop an international civil aviation cybersecurity strategy, it is advisable to use the methodological basis of the Cyber Security Index.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 추계학술발표회 논문집
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• pp.255-269
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• 2011

본 연구에서는 1900년대 이후 근대 한지로 작성된 기록물의 상태를 가능한 빠르게 확인할 수 있는 도구를 연구하고자 비파괴적인 방법으로 분석을 실시하였다. 종이 기록물의 경우 그 자체가 원본임으로 파괴적인 방법으로 분석할 수 없는 한계를 극복하고자 원본을 파괴하지 않고 상태를 확인할 수 있는 방법을 개발하는 것이 본 연구의 목적이다. 본 연구 목적에 적합한 비파괴 분석을 위해 근적외선 분석 장비 중에서 정밀도와 정확도가 좋은 푸리에 변환(Fourier transform) 분석기(spectrometer)를 사용하였다. 또한 측정 대역은 근적외선(NIR) 전체 영역 모두를 측정할 수 있도록 $12,500{\sim}4,000cm^{-1}$ 범위에서 측정하였으며, 분석 대상 한지 기록물을 측정하기 위하여 적분구(integrating sphere)에 접촉하도록 구성 하였다. 한지 기록물의 보존상태를 평가하기 위한 인자로는 화학적 변화 정도를 가장 잘 알 수 있는 산성도(pH)를 사용하였다. 그리고 이들 인자와 근적외선 스펙트럼과 상관관계를 확인하였고, 이때 최적 상관계수를 찾기 위하여 측정한 스펙트럼을 전처리 하였다. 전처리 방법으로는 다산란보정(MSC)과 Savitzky-Golay의 1차 미분을 이용하였다. 상관계수는 부분최소자승법(PLS, Partial least square)으로 확인하였다. 산성도(pH)의 경우에 전처리를 하지 않았을 때의 상관계수($R^2$)는 0.92, 표준예측오차(SEP)는 0.24이었고, 전처리를 하였을 때의 상관계수($R^2$)는 0.98, 표준예측오차(SEP)는 0.19 이었다. 따라서 전처리하였을 때 상관계수와 표준오차가 향상되었음을 알 수 있었다. 또한 1차 미분을 하였을 때의 상관계수($R^2$)는 0.98, 표준예측오차(SEP)는 0.09로써 가장 좋은 표준 예측오차를 얻었다. 따라서 전처리하기 전의 상관계수와 표준오차가 오히려 좋다는 것을 확인하였다. 이러한 결과를 통해 한지 기록물을 적분구와 근적외선 분석기를 이용하여 비파괴적인 방법으로 보다 빠르게 상태를 평가할 수 있을 것으로 판단되었다.

• 한국세라믹학회지
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• 제26권3호
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• pp.305-314
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• 1989

Effect of pH variation in starting solution for the making of hydroxyapatite powder was studied in relation to the sinterability of the powder and their mechanical properties of the sintered hydroxyapatite ceramics. The sinterability of hydroxyapatite powder prepared at different pH was found to be improved with increase in pH value of the starting solutions. Thus the powders prepared from the higher pH solutions including 10.5, 11.0 and 11.5 could be well densified almost upto theoretical density by firing for 1 hr at 1,00$0^{\circ}C$. But the powder based on pH 10 exhibited less sinterability even being fired at much higher temperature of 1,10$0^{\circ}C$, it gave only 90-95% of theoretical density. On the other hand the powder prepared on the lowest pH value 9.5 could not be well densified and it could obtain only 78% of theoretical density even by firing at 1,30$0^{\circ}C$ for 1hr. It was found that prismatic crystals of whitlockite were always included in the sintered bodies based on the lower pH values as a minority crystalline phase together with the major crystalline phase of hydroxyapatite and its inclusion might impair the sinterability of powder. However in the case of the higher pH, the powder contained only hydroxyapatite as a crystalline phase on sintering without any minorities. The sphere shape of crystals might help effectively the densification of the bodies. The best mechanical properties could be obtained from the body of pH 11 sintered at 1,10$0^{\circ}C$, which gave 99.5% of theoretical density, 662Kg/$\textrm{mm}^2$ of vickers hardness and 1,352Kg/$\textrm{cm}^2$ of diameteral compression strength.

• Strategy21
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• 통권30호
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• pp.63-98
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• 2012

Northeast Asia has a multi-layered security structure within which major economic and military powers both confront one another and cooperate at the same time. Major regional powers maintain mutually cooperative activities in the economic sphere while competing one another in order to secure a dominant position in the politico-military arena. The multifarious threats, posed by the North Korea's nuclear development, territorial disputes, and maritime demarcation line issues demonstrate that Northeast Asia suffers more from military conflicts and strifes than any other region in the world. Specifically, major maritime security threats include North Korea's nuclear proliferation and missile launching problems as well as military provocations nearby the Northern Limit Line(NLL) as witnessed in the Cheonan naval ship and Yeonpyong incidents. The ROK Navy has been supplementing its firm military readiness posture in consideration of North Korea's threats on the NLL. It has performed superb roles in defending the nation and establishing the Navy advanced and best picked. It also has been conducive to defend the nation from external military threats and invasion, secure the sea lanes of communications, and establish regional stability and world peace. In order to effectively cope with the strategic environment and future warfares, the ROK Navy needs to shift its military structure to one that is more information and technology intensive. In addition, it should consolidate the ROK-US alliance and extend military cooperative measures with neighboring countries in the Asia-Pacific region. Evolved steadily for the last 60 years, the ROK-US alliance format has contributed to peace and security on the Korean peninsula and in the Northeast Asian region. In conclusion, this manuscript contends that the ROK Navy should strive for the establishment of the following: (1) Construction of Jeju Naval Base; (2) Strategic Navy Equipped with War Deterrence Capabilities; (3) Korean-type of System of Systems; (4) Structure, Budget and Human Resources of the Naval Forces Similar to the Advanced Countries; and (5) Strategic Maritime Alliance and Alignment System as well as Domestic Governance Network for the Naval Families.

• 분석과학
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• 제25권2호
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• pp.121-126
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• 2012

한지기록물의 상태를 평가하는 데 있어 기록물의 훼손을 방지하는 것은 필수적인 요소이다. 사용된 공시재료는 1900년대 생산된 한지기록물을 사용하였다. 이 종이 기록물의 상태를 평가하기 위하여 비파괴적 분석기인 12,500~4,000 $cm^{-1}$ 파장영역을 가진 푸리에변환(FT) 근적외선 분광 분석기를 이용하였다. 푸리에변환 방식의 간섭계는 뛰어난 정밀도와 정확도를 가지며, 신호-대-잡음비가 가장 우수 하여 정량 분석에서 가장 많이 사용되고 있다. 한지기록물의 산성도와 함수율을 적분구(integrating sphere)의 확산반사로 사용하여 측정하였다. 산성도(pH)의 경우에 전처리를 하지 않았을 때의 상관계수($R^2$)는 0.92, 표준예측오차(SEP)는 0.317이었고, 전처리를 하였을 때의 $R^2$는 0.98, SEP는 0.208 이었다. 그리고 함수율의 경우 산성도와 달리 전처리를 하지 않았을 경우에도 $R^2$와 SEP는 각각 0.99와 0.458로 확인 되었다. 전처리 중 다산란 보정방법(MSC)의 경우에는 $R^2$가 0.97, SEP가 0.558로 증가하는 것을 확인 할 수 있어 함수율은 전처리를 하지 않았을 때가 좋은 결과가 나오는 것으로 확인 되었다. 이러한 결과를 통해 비파괴적인 분석방법으로 한지기록물을 적분구와 FT 근적외선 분광 분석기를 이용하여 한지의 상태를 정확히 평가할 수 있을 것으로 판단되었다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1259-1259
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• 2001

Meat becomes brown and rancid during storage in the refrigerator and display in the case. Color changes, metmyoglobin formation and lipid oxidation are the important problems in the transportation / distribution of meat and retail display. The freshness of meat is determined by the sense of vision and smell. Since conventional method determining lipid oxidation is time consuming and destructive (it needs to homogenize meat with reagents, filtrate, time for reaction and read optical density using spectroscopy), more rapid and nondestructive technical tools are desired. The objective of this work was to evaluate near-infrared spectroscopy as an analytical tool for determining meat color, metmyoglobin formation and lipid oxidation. in beef, pork and chicken. Semitendinosus and longissimus thoracis muscles from six beef steers, biceps femoris and longissimus thoracis muscles from twelve LWD crossbred pigs, and superficial pectoral muscles from twenty-four broilers were used. About a 5-cm diameter and 1-cm thick sample (20.0g) was cut from the muscle and placed on plastic foam, over-wrapped with PVC film, and displayed under flourescent lights at 4 degrees C. during 10 days for beef and pork or 4 days for chicken. The spectra was measured by NIR systems Model 5500 Spectrophotometer using fiber optic scan at range of 400 - 1100 nm. Data were recorded at 2 nm intervals and 10 scans / 10 sec were averaged for every sample. Data obtained were saved as log 1/Re, where Re is the reflectance energy, and then mathematically transformed to second derivatives to reduce effects of differences in particle size. $L^{*}$, $a^{*}$ and $b^{*}$, and metmyoglobin formation were determined by conventional spectrophotometer using the integrating sphere unit. 2-Thiobarbituric acid reactive substances (TBARS) were measured for lipid oxidation. A multiple linear regression was used to find the equation which would best fit the data. The number of wavelengths used in the equation was selected based on the fewer number compared to the increasing multiple correlation and Decreasing standard error. (omitted)

• 한국조리학회지
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• 제2권
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• pp.169-181
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• 1996

Today we are inclined to dine out more frequently according as the national income is increased and Women enter into the Social life, 'This tendency results in the universality of foodculture and the food made of fresh food stuff as well as the Pollution-free food is preferable as everyone warits to eat natural food or health food and escapes from the pollution. Moreover we have socail problems like fatress and adult disease which result from the small amount of activity or the food with high calory and high gat. under this circumstance. the most adeguate food seems to be Italian good. It stand in the spottight of food world and is most preferable for everyone today. The sphere of food and beverage has a low value-added-rate compartry to the high increasing rate of customers and profit, so, the efficient managing method for the cost of food and beverage and the operating skill in the kitchen are the principal factors leading to success or failure. Therefore, this research is to show some remedies as follows, pointing out the operating problems of an selected Italian restaurant at the top class hotel. First, most Italian restaurant at the hotel are located in the best place and investing the big capital, But they are open for only 8 hours through a day. This should be improved not to bring a enormous loss to the hotel The brealefast menus such as vegetables or fish food, pizza and pasta which modern man can easily enjoy should be developed open the restaurants for morning gours. Second, the business hours are not made continously. As a result, all the emplyees should stay in the company all day long without taking any advantage of the losed time, This will be the loss for both the company and the employees, By veloping the morning menus, employees shald be classified into morning and afternoon staffs and the opening and closing hour at 3 and 6 O'clock should be used so that minimum number of employees may operate the company. Third, the characteristic of Italian food is in the use of fresh food stuff, The proper purchase of food stuff and the simple distributing system will help Italian restaurant show its character istcc as a hzgh-grade restaurant. Fourth, the most popular Italian food such as pizza or pasta should be market with Priority.

• 한국산학기술학회논문지
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• 제14권9호
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• pp.4587-4592
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• 2013

GPS는 측량, 지도제작 및 항법 이외에도 고정밀 측위에 의한 세계기준좌표계 설정, 지구 자전축의 회전계수 결정, 지진 및 지각변동 감지 등과 같은 지구과학 분야의 필수적인 방법으로 인식되고 있다. 그러나 정밀 해석결과를 얻기 위해서는 자료처리를 위한 전문지식과 비용 투자가 필요하므로, 사용자들이 손쉽게 결과를 획득할 수 있는 방안이 필요하다. 이에 본 연구에서는 비전문가도 정밀절대측위 방법으로 GPS 자료처리가 가능한 정밀절대측위 솔루션을 개발하고자 하였다. 연구를 통해 자료처리에 필요한 최소 정보만을 입력함으로써 사용자의 편의성을 크게 향상시킨 솔루션을 개발하였다. 또한 국토지리정보원에서 제공하는 위성기준점의 관측자료를 정밀절대측위로 처리하여, 지각변동 속도를 산출하고, ITRF에서 제공하는 지각변동 속도와 비교를 통해 정밀절대측위 솔루션을 이용한 지진 및 지각변동 감지가 가능함을 제시하였다.