• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.241-241
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• 2012

Semiconductor industry has been taking the advantage of improvements in process technology in order to maintain reduced device geometries and stringent performance specifications. This results in semiconductor manufacturing processes became hundreds in sequence, it is continuously expected to be increased. This may in turn reduce the yield. With a large amount of investment at stake, this motivates tighter process control and fault diagnosis. The continuous improvement in semiconductor industry demands advancements in process control and monitoring to the same degree. Any fault in the process must be detected and classified with a high degree of precision, and it is desired to be diagnosed if possible. The detected abnormality in the system is then classified to locate the source of the variation. The performance of a fault detection system is directly reflected in the yield. Therefore a highly capable fault detection system is always desirable. In this research, time series modeling of the data from an etch equipment has been investigated for the ultimate purpose of fault diagnosis. The tool data consisted of number of different parameters each being recorded at fixed time points. As the data had been collected for a number of runs, it was not synchronized due to variable delays and offsets in data acquisition system and networks. The data was then synchronized using a variant of Dynamic Time Warping (DTW) algorithm. The AutoRegressive Integrated Moving Average (ARIMA) model was then applied on the synchronized data. The ARIMA model combines both the Autoregressive model and the Moving Average model to relate the present value of the time series to its past values. As the new values of parameters are received from the equipment, the model uses them and the previous ones to provide predictions of one step ahead for each parameter. The statistical comparison of these predictions with the actual values, gives us the each parameter's probability of fault, at each time point and (once a run gets finished) for each run. This work will be extended by applying a suitable probability generating function and combining the probabilities of different parameters using Dempster-Shafer Theory (DST). DST provides a way to combine evidence that is available from different sources and gives a joint degree of belief in a hypothesis. This will give us a combined belief of fault in the process with a high precision.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.434-435
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• 2012

Plasma enhanced chemical vapor deposition (PECVD) silicon dioxide thin films have many applications in semiconductor manufacturing such as inter-level dielectric and gate dielectric metal oxide semiconductor field effect transistors (MOSFETs). Fundamental chemical reaction for the formation of SiO2 includes SiH4 and O2, but mixture of SiH4 and N2O is preferable because of lower hydrogen concentration in the deposited film [1]. It is also known that binding energy of N-N is higher than that of N-O, so the particle generation by molecular reaction can be reduced by reducing reactive nitrogen during the deposition process. However, nitrous oxide (N2O) gives rise to nitric oxide (NO) on reaction with oxygen atoms, which in turn reacts with ozone. NO became a greenhouse gas which is naturally occurred regulating of stratospheric ozone. In fact, it takes global warming effect about 300 times higher than carbon dioxide (CO2). Industries regard that N2O is inevitable for their device fabrication; however, it is worthwhile to develop a marginable nitrous oxide free process for university lab classes considering educational and environmental purpose. In this paper, we developed environmental friendly and material cost efficient SiO2 deposition process by substituting N2O with O2 targeting university hands-on laboratory course. Experiment was performed by two level statistical design of experiment (DOE) with three process parameters including RF power, susceptor temperature, and oxygen gas flow. Responses of interests to optimize the process were deposition rate, film uniformity, surface roughness, and electrical dielectric property. We observed some power like particle formation on wafer in some experiment, and we postulate that the thermal and electrical energy to dissociate gas molecule was relatively lower than other runs. However, we were able to find a marginable process region with less than 3% uniformity requirement in our process optimization goal. Surface roughness measured by atomic force microscopy (AFM) presented some evidence of the agglomeration of silane related particles, and the result was still satisfactory for the purpose of this research. This newly developed SiO2 deposition process is currently under verification with repeated experimental run on 4 inches wafer, and it will be adopted to Semiconductor Material and Process course offered in the Department of Electronic Engineering at Myongji University from spring semester in 2012.

• Science of Emotion and Sensibility
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• v.11 no.1
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• pp.105-112
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• 2008

This study investigated the effect of 40% oxygen administration on the addition task performance in three levels of difficulties and physiological signals. Ten male and female college students were selected as the subjects for this study. The experiment consisted of two runs: one was a addition task, with normal air (21% oxygen) administered and the other was with hyperoxic air (40% oxygen) administered. The experimental sequence in each run consisted of Rest1 (3 min), Task1 (1 min, one digit addition task), Task2 (1 min, two digit addition task), Task3 (1 min, three digit addition task), and Rest2 (4 min). Blood oxygen saturation and heart rate were measured throughout the five phases. The accuracy rates of the addition task were enhanced with 40% oxygen administration compared to 21% oxygen. Difference in the accuracy rates grew higher with the rise of difficulty. When 40% concentration oxygen is supplied, blood oxygen saturation increased and heart rate was decreased comparing to 21%. This study showed that the supply of high concentration oxygen increases blood oxygen saturation, which in turns accelerates brain activation resulting from cognitive process and enhances arithmetic abilities. Particularly when difficulty is high, demand for oxygen increases and, as a result, the effect of high concentration oxygen becomes more significant.

• Journal of Environmental Impact Assessment
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• v.23 no.4
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• pp.271-284
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• 2014

The objectives of this research were to analyse the microhabitat of Cobitis choii which is designated as an endangered fish species (I) and national monument species in Korea (No. 454), and provide valuable information of suitable replacement habitat in the future for a conservation of the population with rapid decreases by environmental pollution. Sampling and microhabitat analysis in three streams such as Baekgok, Yugu and Gap Stream, known as one of the least habitats in Korea showed that the mean number of Cobitis choii observed was 2.6. This result indicated that the richness was too low, so the species conservation was very urgent. Optimal physical microhabitat of the population was determined as environmental conditions with > 60% sand with 1 mm particle size, optimal water depth of 20 - 60 cm in the habitats, and the optimal current velocity of < 0.4 m/s. Under the circumstances of the microhabitat, optimal water volume (discharge) was 0 - 2 m3/s in the each sectional analysis and this reach was mainly composed of the stream section with intermittant slow runs and pools. These microhabitats were largely disturbed by physical modifications of habitat and chemical pollutions due to direct influences of nutrient-rich water inputs from the urban area and intensive agricultural pollutants. For these reasons, optimal habitat replacement are required in the future for the conservation of the species.

• Journal of Life Science
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• v.20 no.11
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• pp.1729-1737
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• 2010

This study was conducted to establish the optimal medium condition for the animal probiotic Lactobacillus plantarum by using onion juice. Cell yield and antioxidant activity increased in proportion to high additive levels of onion juice in medium. Onion juice, sucrose and yeast extract were selected as media ingredient factors and the effects of their mixed ratio in medium were evaluated. The full factorial design consisted of 24 experimental runs and was employed to estimate the main effects of the factors and their interactions. Significant positive effects on cell yield and antioxidant activity was shown with yeast extract and onion juice, respectively. Significant interaction was found only between sucrose and yeast extract in antioxidant activity. Finally, we selected an optimal medium that was composed of (g/l) onion juice, 600; sucrose, 15; yeast extract, 5. The efficiency of this optimum medium was estimated by using a 5 l jar fermenter. As a result, the maximum cell yield was $9.7\;{\log}_{10}$ (CFU/ml) at 12 hr. Cell yield at the end of incubation (20 hr) was $8.9\;{\log}_{10}$ (CFU/ml) and it was very similar with the predicted value, $9.0\;{\log}_{10}$ (CFU/ml). Antioxidant activity of culture was maintained at about 60~65% during all incubation time, resulting in a higher-than-predicted activity of 47.1%.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.10-17
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• 2015

Emotional computer that you want to study in a regular number change is the continuing sensitivity. Emotional Computing manner the sensibilities numbered and emotions were running through the trees. Emotional assessment of emotional sensibility computing was used as the coordinates of the key effects of the James A. Russell (Core Affect). Emotional tree runs purpose was to verify the correlation of sensitivity and emotion computing tree. Emotional tree attributes experiment color, brightness, saturation was configured with. When 50% brightness increase, about pleasure (X-axis) has increased by 10.49 points. Brightness 50%, GREEN 50% increase in the degree of pleasure (X-axis) of 10.49 points, tone (Y axis) has increased by 15.85 points. Brightness 50%, GREEN 50% increase in the degree of pleasure (X-axis) of 10.49 points, tone (Y axis) has increased by 15.85 points. Brightness 50% of the free-extent (X-axis), BLUE 50% when the tone (Y axis), pleasure extent (X-axis) of 10.49 points, tone (Y axis) as much as 14.65 points sensibilities have changed. When representatives emotions size changes have increased 50% brightness, color RED 50%, increased 5.4% Emotional excitement, emotion depressed declined -4.2%. 50% brightness, color GREEN 50% increase in emotional excitement had increased to 8.6%, declined by -5.5% this melancholy sensibility. Representative emotion and emotional changes increase or decrease the size of the emotional attributes were analyzed by quantitative methods. After the happy emotions number is needed to study more similar to the human emotion through the execution of the video image emotion emotional tree computing.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.5B
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• pp.512-521
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• 2003

In this paper, we introduce our experience of the design and implementation of mobile collaboration system(MCS) that support people using mobile devices to participate in cooperative session. There are considerable differences between desktop PC and mobile devices like PDA in processing ability, resolution of display and color degree. In the case of mobile devices, they use different processors and different operating system and they have even differences in ability of executing application. The mobile collaborative system based on T.120 protocol of ITU-T standard compromised of mobile collaboration server, mobile collaboration client, session node and application. We also define the session node in desktop PC in which session control block and communication block runs. This node provide functions of session control block and communication block to mobile collaboration clients and so lighten load of clients. The mobile collaboration server provides information of candidates for session node, session and user to mobile collaboration client. And this server support clients to configure their own session node and manage sessions. Only the mobile collaboration client module and applications including APE are executed in a mobile device when user using mobile devices would like to participate in cooperative session. We implemented mobile collaboration client and applications with JAVA to support platform independency.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.12B
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• pp.1708-1721
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• 2011

Recent outbreak of cattle diseases such as foot-and-mouth disease(FMD) requires constant monitoring of burial sites of mass cull of cattles. However, current monitoring system takes environmental samples from burial sites with period of between one and two weeks, which makes it impossible for non-stop management of hazardous bio-waste. Therefore, in this study, we suggest an improved real-time environmental monitoring system for such bio-hazardous sites based on wireless sensor networks, which makes constant surveillance of the FMD burial sites possible. The system consists mainly several wireless environmental monitoring sensors(i.e dust, Co2, VOC, NH3, H2S, temperature, humidity) nodes and GPS location tracking nodes. Through analysis of the relayed of the environmental monitoring data via gateway, the system makes it possible for constant monitoring and quick response for emergency situation of the burial sites. In order to test the effectiveness of the system, we have installed a set of sensor to gas outlets of the burial sites, then collected and analyzed measured bio-sensing data. We have conducted simulated emergency test runs and was able to detect and monitor the foul smell constantly. With our study, we confirm that the preventive measures and quick response of bio environmental accident are possible with the help of a real-time environmental monitoring system.

• Korean Journal of Acupuncture
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• v.18 no.1
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• pp.105-116
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• 2001

We examined and referred to some literatures on the meaning, Dai meridian and Meridian points of joining with circulation of Dai meridian through literatures of every generation. And then we came to get a few conclusions as follows. 1. Dai meridian starts below the hypochondriac region. Running obliquely downward, it runs transversely around the waist like a belt. Its function is to bind up all the meridians to circulate in a proper way. 2. The coalescent points of dai meridian are $D\grave{a}im\grave{a}i$(帶脈), $W\check{u}sh\bar{u}$(五樞) and $W\acute{e}id\grave{a}o$(維道). 3. Location of $D\grave{a}im\grave{a}i$(帶脈) is on the lateral side of the abdomen, 1.8 cun below $Zh\bar{a}ngm\grave{e}n$(章門), at the crossing point of vertical line through the free end of the 11th rib and a horizontal line through the umbilicus. Location of $W\check{u}sh\bar{u}$(五樞) is on the lateral side of the abdomen, anterior to the anterosuperior iliac spine, 3 cun below the level of the umbilicus. Location of $W\acute{e}id\grave{a}o$(維道) is on the lateral side of the abdomen, anterior and inferior to the anterosuperior iliac spine, 0.5 cun anterior and inferior to $W\check{u}sh\bar{u}$(五樞). 4. Indication of $D\grave{a}im\grave{a}i$(帶脈) is irregular menstruation, leukorrhea with reddish discharge, hernia, pain in the lumbar and hypochondriac region. Indication of $W\check{u}sh\bar{u}$(五樞) is prolapse of the uterus, leukorrhea with reddish discharge, irregular menstruation, hernia, pain in the lower abdomen, constipation and lumbosacral pain. Indication of $W\acute{e}id\grave{a}o$(維道) is edema, pain in the side of the lower abdomen, prolapse of the uterus, hernia and morbid leukorrhea. 5. The Dai meridian binds all meridians, produces pregnancy, grasps lumbar and abdomen region and controls leukorrhea. 6. Diseases of the Dai meridian manifested as distention and fullness in the lumbar region and abdomen, leukorrhea with reddish discharge, pain the navel, lumbar and spinal regions, flaccidity and hypoactivity of the lower limbs, etc.

• Korean Security Journal
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• no.55
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• pp.169-192
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• 2018

This article assesses the recent police reform strategy in England and Wales with the Police Reform and Social Responsibility Act 2011. Police and Crime Commissioners have a responsibility not just for the police force but also for reducing crime in their area of responsibility. This ensures that their remit runs much more widely than their predecessor body, the police authority. The article goes on to evaluate the nature and extent of crime by making immediate use of survey of local police commanders. The surveys showed that police commands were swamped with minor crime and anti-social offences. The arrival of Police and Crime Commissioners has meant that now police priorities can be more closely aligned to those of the public and where anti-social behaviour is now recognised as impacting on the lives of many residents more significantly than criminal activity. The article highlights the changes introduced by government following the Winsor Review to police pay, pensions and conditions of service. It reflects on the impact of this on both police morale and professional motivation. It suggests that current government policy is now haemorrhaging the police service as increasing numbers of experienced officers are leaving the police service which could ultimately undermine its long-term resilience as a strategic emergency service.