• Title/Summary/Keyword: Network system

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T-Cache: a Fast Cache Manager for Pipeline Time-Series Data (T-Cache: 시계열 배관 데이타를 위한 고성능 캐시 관리자)

  • Shin, Je-Yong;Lee, Jin-Soo;Kim, Won-Sik;Kim, Seon-Hyo;Yoon, Min-A;Han, Wook-Shin;Jung, Soon-Ki;Park, Se-Young
    • Journal of KIISE:Computing Practices and Letters
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    • v.13 no.5
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    • pp.293-299
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    • 2007
  • Intelligent pipeline inspection gauges (PIGs) are inspection vehicles that move along within a (gas or oil) pipeline and acquire signals (also called sensor data) from their surrounding rings of sensors. By analyzing the signals captured in intelligent PIGs, we can detect pipeline defects, such as holes and curvatures and other potential causes of gas explosions. There are two major data access patterns apparent when an analyzer accesses the pipeline signal data. The first is a sequential pattern where an analyst reads the sensor data one time only in a sequential fashion. The second is the repetitive pattern where an analyzer repeatedly reads the signal data within a fixed range; this is the dominant pattern in analyzing the signal data. The existing PIG software reads signal data directly from the server at every user#s request, requiring network transfer and disk access cost. It works well only for the sequential pattern, but not for the more dominant repetitive pattern. This problem becomes very serious in a client/server environment where several analysts analyze the signal data concurrently. To tackle this problem, we devise a fast in-memory cache manager, called T-Cache, by considering pipeline sensor data as multiple time-series data and by efficiently caching the time-series data at T-Cache. To the best of the authors# knowledge, this is the first research on caching pipeline signals on the client-side. We propose a new concept of the signal cache line as a caching unit, which is a set of time-series signal data for a fixed distance. We also provide the various data structures including smart cursors and algorithms used in T-Cache. Experimental results show that T-Cache performs much better for the repetitive pattern in terms of disk I/Os and the elapsed time. Even with the sequential pattern, T-Cache shows almost the same performance as a system that does not use any caching, indicating the caching overhead in T-Cache is negligible.

The Construction Direction of the ROK NAVY for the Protection of Marine Sovereignty (국가의 해양주권 수호를 위한 한국해군의 전력건설 방향)

  • Shin, In-Kyun
    • Strategy21
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    • s.30
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    • pp.99-142
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    • 2012
  • Withe increased North Korea's security threats, the South Korean navy has been faced with deteriorating security environment. While North Korea has increased asymmetric forces in the maritime and underwater with the development of nuclear weapons, and China and Japan have made a large investment in the buildup of naval forces, the power of the Pacific fleet of the US, a key ally is expected to be weakened. The biggest threat comes from China's intervention in case of full-scale war with North Korea, but low-density conflict issues are also serious problems. North Korea has violated the Armistice Agreement 2,660 times since the end of Korean War, among which the number of marine provocations reaches 1,430 times, and the tension over the NLL issue has been intensifying. With tension mounting between Korea and Japan over the Dokdo issue and conflict escalating with China over Ieo do Islet, the US Navy has confronted situation where it cannot fully concentrate on the security of the Korean peninsula, which leads to need for strengthening of South Korea's naval forces. Let's look at naval forces of neighboring countries. North Korea is threatening South Korean navy with its increased asymmetric forces, including submarines. China has achieved the remarkable development of naval forces since the promotion of 3-step plan to strengthen naval power from 1989, and it now retains highly modernized naval forces. Japan makes an investment in the construction of stat of the art warship every year. Since Japan's warship boasts of its advanced performance, Japan's Maritime Self Defense Force is evaluated the second most powerful behind the US Navy on the assumption that submarine power is not included in the naval forces. In this situation, naval power construction of South Korean navy should be done in phases, focusing on the followings; First, military strength to repel the energy warship quickly without any damage in case of battle with North Korea needs to be secured. Second, it is necessary to develop abilities to discourage the use of nuclear weapons of North Korea and attack its nuclear facilities in case of emergency. Third, construction of military power to suppress armed provocations from China and Japan is required. Based on the above naval power construction methods, the direction of power construction is suggested as follows. The sea fleet needs to build up its war potential to defeat the naval forces of North Korea quickly and participate in anti-submarine operations in response to North Korea's provocations. The task fleet should be composed of 3 task flotilla and retain the power to support the sea fleet and suppress the occurrence of maritime disputes with neighboring countries. In addition, it is necessary to expand submarine power, a high value power asset in preparation for establishment of submarine headquarters in 2015, develop anti-submarine helicopter and load SLAM-ER missile onto P-3C patrol aircraft. In case of maine corps, division class military force should be able to conduct landing operations. It takes more than 10 years to construct a new warship. Accordingly, it is necessary to establish plans for naval power construction carefully in consideration of reality and future. For the naval forces to safeguard maritime sovereignty and contribute to national security, the acquisition of a huge budget and buildup of military power is required. In this regard, enhancement of naval power can be achieved only through national, political and military understanding and agreement. It is necessary to let the nation know that modern naval forces with improved weapon system can serve as comprehensive armed forces to secure the command of the sea, perform defense of territory and territorial sky and attack the enemy's strategic facilities and budget inputted in the naval forces is the essential source for early end of the war and minimization of damage to the people. If the naval power construction is not realized, we can be faced with a national disgrace of usurpation of national sovereignty of 100 years ago. Accordingly, the strengthening of naval forces must be realized.

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A Study on the Validity of Rural Type Low Carbon Green Village Through Case Analysis (사례분석을 통한 농촌형 저탄소 녹색마을 타당성 검토)

  • Do, In-Hwan;Hwang, Eun-Jin;Hong, Soo-Youl;Phae, Chae-Gun
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.12
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    • pp.913-921
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    • 2011
  • This study examined the overall feasibility of low carbon green village formed in rural area. The check method is analyzing its environmental and economic feasibility and energy self-reliance. The biomass of the villages was set as 28 ton/day of livestock feces and 2 ton/day of cut fruit tree branches which make up the total of 30 ton/day. The facility consisted of a bio gasfication facility using wet (livestock feces) biomass and combined heat power generator, composting facility and wood boiler using dry (cut fruit tree branches) biomass. When operating the system, 540,540 kWh/yr of electricity and 1,762 Gcal/yr of heat energy was produced. The region's electricity energy and heat energy self-reliance rate will be 100%. The economic feasibility was found as a loss of 140 million won where the facility installation cost is 5.04 billion won, operation cost is 485.09 million won and profit is 337.12 million won. There will be a loss of about 2.2 billion won in 15 years but in the environmental analysis, it was found that crude replacement effect is about 178 million won, greenhouse gas reduction effect is about 92 million won making up the total environmental benefit of 270 million won. This means, there will be a yearly profit of about 130 million won. In terms of its environmental and economic feasibility and energy self-reliance, this project seemed to be a feasible project in overall even if it manages to get help from the government or local government.

Inhibition of Graft Versus Host Disease Using CD4+CD25+ T Cells Induced with Interleukin-2 in Mismatched Allogeneic Murine Hematopoietic Stem Cell Transplantation (주조직적합항원이 불일치하는 마우스 동종 조혈모세포이식에서 IL-2로 유도된 CD4+CD25+ T세포를 이용한 이식편대숙주병의 억제)

  • Hyun, Jae Ho;Jeong, Dae Chul;Chung, Nak Gyun;Park, Soo Jeong;Min, Woo Sung;Kim, Tai Gyu;Choi, Byung Ock;Kim, Won Il;Han, Chi Wha;Kim, Hack Ki
    • IMMUNE NETWORK
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    • v.3 no.4
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    • pp.287-294
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    • 2003
  • Background: In kidney transplantation, donor specific transfusion may induce tolerance as a result of some immune regulatory cells against the graft. In organ transplantation, the immune state arises from a relationship between the immunocompromised graft and the immunocompetent host. However, a reverse immunological situation exists between the graft and the host in hematopoietic stem cell transplantation (HSCT). In addition, early IL-2 injections after an allogeneic murine HSCT have been shown to prevent lethal graft versus host disease (GVHD) due to CD4+ cells. We investigated the induction of the regulatory CD4+CD25+ cells after a transfusion of irradiated recipient cells with IL-2 into a donor. Methods: The splenocytes (SP) were obtained from 6 week-old BALB/c mice ($H-2^d$) and irradiated as a single cell suspension. The donor mice (C3H/He, $H-2^k$) received $5{\times}10^6$ irradiated SP, and 5,000 IU IL-2 injected intraperitoneally on the day prior to HSCT. The CD4+CD25+ cell populations in SP treated C3H/He were analyzed. In order to determine the in vivo effect of CD4+CD25+ cells, the lethally irradiated BALB/c were transplanted with $1{\times}10^7$ donor BM and $5{\times}10^6$ CD4+CD25+ cells. The other recipient mice received either $1{\times}10^7$ donor BM with $5{\times}10^6$ CD4+ CD25- cells or the untreated SP. The survival and GVHD was assessed daily by a clinical scoring system. Results: In the MLR assay, BALB/c SP was used as a stimulator with C3H/He SP, as a responder, with or without treatment. The inhibition of proliferation was $30.0{\pm}13%$ compared to the control. In addition, the MLR with either the CD4+CD25+ or CD4+CD25- cells, which were isolated by MidiMacs, from the C3H/He SP treated with the recipient SP and IL-2 was evaluated. The donor SP treated with the recipient cells and IL-2 contained more CD4+CD25+ cells ($5.4{\pm}1.5%$) than the untreated mice SP ($1.4{\pm}0.3%$)(P<0.01). There was a profound inhibition in the CD4+CD25+ cells ($61.1{\pm}6.1%$), but a marked proliferation in the CD4+CD25- cells ($129.8{\pm}65.2%$). Mice in the CD4+CD25+ group showed low GVHD scores and a slow progression from the post-HSCT day 4 to day 9, but those in the control and CD4+CD25- groups had a high score and rapid progression (P<0.001). The probability of survival was 83.3% in the CD4+CD25+ group until post-HSC day 35 and all mice in the control and CD4+CD25- groups died on post-HSCT day 8 or 9 (P=0.0105). Conclusion: Donor graft engineering with irradiated recipient SP and IL-2 (recipient specific transfusion) can induce abundant regulatory CD4+CD25+ cells to prevent GVHD.

Building battery deterioration prediction model using real field data (머신러닝 기법을 이용한 납축전지 열화 예측 모델 개발)

  • Choi, Keunho;Kim, Gunwoo
    • Journal of Intelligence and Information Systems
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    • v.24 no.2
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    • pp.243-264
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    • 2018
  • Although the worldwide battery market is recently spurring the development of lithium secondary battery, lead acid batteries (rechargeable batteries) which have good-performance and can be reused are consumed in a wide range of industry fields. However, lead-acid batteries have a serious problem in that deterioration of a battery makes progress quickly in the presence of that degradation of only one cell among several cells which is packed in a battery begins. To overcome this problem, previous researches have attempted to identify the mechanism of deterioration of a battery in many ways. However, most of previous researches have used data obtained in a laboratory to analyze the mechanism of deterioration of a battery but not used data obtained in a real world. The usage of real data can increase the feasibility and the applicability of the findings of a research. Therefore, this study aims to develop a model which predicts the battery deterioration using data obtained in real world. To this end, we collected data which presents change of battery state by attaching sensors enabling to monitor the battery condition in real time to dozens of golf carts operated in the real golf field. As a result, total 16,883 samples were obtained. And then, we developed a model which predicts a precursor phenomenon representing deterioration of a battery by analyzing the data collected from the sensors using machine learning techniques. As initial independent variables, we used 1) inbound time of a cart, 2) outbound time of a cart, 3) duration(from outbound time to charge time), 4) charge amount, 5) used amount, 6) charge efficiency, 7) lowest temperature of battery cell 1 to 6, 8) lowest voltage of battery cell 1 to 6, 9) highest voltage of battery cell 1 to 6, 10) voltage of battery cell 1 to 6 at the beginning of operation, 11) voltage of battery cell 1 to 6 at the end of charge, 12) used amount of battery cell 1 to 6 during operation, 13) used amount of battery during operation(Max-Min), 14) duration of battery use, and 15) highest current during operation. Since the values of the independent variables, lowest temperature of battery cell 1 to 6, lowest voltage of battery cell 1 to 6, highest voltage of battery cell 1 to 6, voltage of battery cell 1 to 6 at the beginning of operation, voltage of battery cell 1 to 6 at the end of charge, and used amount of battery cell 1 to 6 during operation are similar to that of each battery cell, we conducted principal component analysis using verimax orthogonal rotation in order to mitigate the multiple collinearity problem. According to the results, we made new variables by averaging the values of independent variables clustered together, and used them as final independent variables instead of origin variables, thereby reducing the dimension. We used decision tree, logistic regression, Bayesian network as algorithms for building prediction models. And also, we built prediction models using the bagging of each of them, the boosting of each of them, and RandomForest. Experimental results show that the prediction model using the bagging of decision tree yields the best accuracy of 89.3923%. This study has some limitations in that the additional variables which affect the deterioration of battery such as weather (temperature, humidity) and driving habits, did not considered, therefore, we would like to consider the them in the future research. However, the battery deterioration prediction model proposed in the present study is expected to enable effective and efficient management of battery used in the real filed by dramatically and to reduce the cost caused by not detecting battery deterioration accordingly.

A Study on the Activation Factors of Voluntary Community Activities in Neighborhood Parks - Based on the People Who Love Chamsaem in Sejong City - (근린 생활권 공원에서의 자발적 공동체 활동의 활성화 요인에 관한 연구 - 세종시 '참샘을 사랑하는 모임'을 대상으로 -)

  • Kim, Woo-Joo;Lee, Cha-Hee;Sung, Jong-Sang
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.2
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    • pp.37-51
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    • 2018
  • Recently, urban parks are required to actively participate with residents in order to strengthen social functions and maintain sustainable management. This study analyzed the formation process of volunteer resident groups (Chamsamo) in the neighborhood parks in which local residents can participate in an ongoing basis based on the solidarity of a daily living space. The important factors in the activation of resident activity are derived from 5 aspects including resources, local area, resident group capacity, resident group role, and public support. The results of the study are as follows. 1) Life-friendly resources: It was important to find life-friendly resources such as 'Chamsaem' in the park. The combined resources of continuous human activities provided various benefits to the residents. This has led to stronger attachment and community activities to continue to utilize attractive resources in the park. 2) Sharing Common Daily Spaces and Expansion: As the Chamsamo activities were centered around the neighborhood, the network of activists in the local community expanded. This led to continued resident interest and favorable participation as well as to the regional expansion of Chamsamo activities. 3) Park management as part of everyday life: Park management became a part of everyday life, and pleasant park management was facilitated by utilizing the talents of the residents, who carried out diverse activities and constantly streamlined their hard labor. 4) Chamsamo's Leadership Linking Residents and the Public Sector through Leading Park Management Activities: Chamsamo served as a middle leader in linking the public sector and its users. 5) Role and Support of the Public Sector: In order to be able to sustain the activities of residents, the government's willingness to support the resident-led activities of the park in planning and operating the public sector was required. In the public management system of the park, support for residents' activities such as financing, education, and consulting was necessary.

Analysis of the Effects of Radio Traffic Information on Urban Worker's Travel Choice Behavior (교통방송이 제공하는 교통정보가 직장인의 통행행태에 미치는 영향 분석)

  • 윤대식
    • Journal of Korean Society of Transportation
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    • v.20 no.5
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    • pp.33-43
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    • 2002
  • Travel choice behavior is affected by real-time traffic information. Recently, in urban area, real-time traffic information is provided by several instruments such as transportation broadcasting, internet PC network and variable message sign, etc. Furthermore, it has been increasing for urban travelers to use real-time traffic information provided by several instruments. The purpose of this study is to analyze the effects of advanced traveler information on urban worker's travel choice behavior. Among several Advanced Traveler Information System(ATIS) employed in urban area. This study focuses on examining the effects of transportation broadcasting on urban worker's travel choice behavior. This study attempts to examine traveler's mode change behavior in the pre-trip stage and traveler's route change behavior in the on-route stage. For this study, the survey data collected from Daegu City in 2000 is used. For empirical analysis, several nested logit models are estimated, and among them, the best models are reported in this paper. Furthermore, based on the empirical models estimated for this research, important findings and their policy implications are discussed.

A Study On Design of ZigBee Chip Communication Module for Remote Radiation Measurement (원격 방사선 측정을 위한 ZigBee 원칩형 통신 모듈 설계에 대한 연구)

  • Lee, Joo-Hyun;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.18 no.4
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    • pp.552-558
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    • 2014
  • This paper suggests how to design a ZigBee-chip-based communication module to remotely measure radiation level. The suggested communication module consists of two control processors for the chip as generally required to configure a ZigBee system, and one chip module to configure a ZigBee RF device. The ZigBee-chip-based communication module for remote radiation measurement consists of a wireless communication controller; sensor and high-voltage generator; charger and power supply circuit; wired communication part; and RF circuit and antenna. The wireless communication controller is to control wireless communication for ZigBee and to measure radiation level remotely. The sensor and high-voltage generator generates 500 V in two consecutive series to amplify and filter pulses of radiation detected by G-M Tube. The charger and power supply circuit part is to charge lithium-ion battery and supply power to one-chip processors. The wired communication part serves as a RS-485/422 interface to enable USB interface and wired remote communication for interfacing with PC and debugging. RF circuit and antenna applies an RLC passive component for chip antenna to configure BALUN and antenna impedance matching circuit, allowing wireless communication. After configuring the ZigBee-chip-based communication module, tests were conducted to measure radiation level remotely: data were successfully transmitted in 10-meter and 100-meter distances, measuring radiation level in a remote condition. The communication module allows an environment where radiation level can be remotely measured in an economically beneficial way as it not only consumes less electricity but also costs less. By securing linearity of a radiation measuring device and by minimizing the device itself, it is possible to set up an environment where radiation can be measured in a reliable manner, and radiation level is monitored real-time.

Landslide Vulnerability Mapping considering GCI(Geospatial Correlative Integration) and Rainfall Probability In Inje (GCI(Geospatial Correlative Integration) 및 확률강우량을 고려한 인제지역 산사태 취약성도 작성)

  • Lee, Moung-Jin;Lee, Sa-Ro;Jeon, Seong-Woo;Kim, Geun-Han
    • Journal of Environmental Policy
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    • v.12 no.3
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    • pp.21-47
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    • 2013
  • The aim is to analysis landslide vulnerability in Inje, Korea, using GCI(Geospatial Correlative Integration) and probability rainfalls based on geographic information system (GIS). In order to achieve this goal, identified indicators influencing landslides based on literature review. We include indicators of exposure to climate(rainfall probability), sensitivity(slope, aspect, curvature, geology, topography, soil drainage, soil material, soil thickness and soil texture) and adaptive capacity(timber diameter, timber type, timber density and timber age). All data were collected, processed, and compiled in a spatial database using GIS. Karisan-ri that had experienced 470 landslides by Typhoon Ewinia in 2006 was selected for analysis and verification. The 50% of landslide data were randomly selected to use as training data, while the other 50% being used for verification. The probability of landslides for target years (1 year, 3 years, 10 years, 50 years, and 100 years) was calculated assuming that landslides are triggered by 3-day cumulative rainfalls of 449 mm. Results show that number of slope has comparatively strong influence on landslide damage. And inclination of $25{\sim}30^{\circ}C$, the highest correlation landslide. Improved previous landslide vulnerability methodology by adopting GCI. Also, vulnerability map provides meaningful information for decision makers regarding priority areas for implementing landslide mitigation policies.

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A digital Audio Watermarking Algorithm using 2D Barcode (2차원 바코드를 이용한 오디오 워터마킹 알고리즘)

  • Bae, Kyoung-Yul
    • Journal of Intelligence and Information Systems
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    • v.17 no.2
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    • pp.97-107
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    • 2011
  • Nowadays there are a lot of issues about copyright infringement in the Internet world because the digital content on the network can be copied and delivered easily. Indeed the copied version has same quality with the original one. So, copyright owners and content provider want a powerful solution to protect their content. The popular one of the solutions was DRM (digital rights management) that is based on encryption technology and rights control. However, DRM-free service was launched after Steve Jobs who is CEO of Apple proposed a new music service paradigm without DRM, and the DRM is disappeared at the online music market. Even though the online music service decided to not equip the DRM solution, copyright owners and content providers are still searching a solution to protect their content. A solution to replace the DRM technology is digital audio watermarking technology which can embed copyright information into the music. In this paper, the author proposed a new audio watermarking algorithm with two approaches. First, the watermark information is generated by two dimensional barcode which has error correction code. So, the information can be recovered by itself if the errors fall into the range of the error tolerance. The other one is to use chirp sequence of CDMA (code division multiple access). These make the algorithm robust to the several malicious attacks. There are many 2D barcodes. Especially, QR code which is one of the matrix barcodes can express the information and the expression is freer than that of the other matrix barcodes. QR code has the square patterns with double at the three corners and these indicate the boundary of the symbol. This feature of the QR code is proper to express the watermark information. That is, because the QR code is 2D barcodes, nonlinear code and matrix code, it can be modulated to the spread spectrum and can be used for the watermarking algorithm. The proposed algorithm assigns the different spread spectrum sequences to the individual users respectively. In the case that the assigned code sequences are orthogonal, we can identify the watermark information of the individual user from an audio content. The algorithm used the Walsh code as an orthogonal code. The watermark information is rearranged to the 1D sequence from 2D barcode and modulated by the Walsh code. The modulated watermark information is embedded into the DCT (discrete cosine transform) domain of the original audio content. For the performance evaluation, I used 3 audio samples, "Amazing Grace", "Oh! Carol" and "Take me home country roads", The attacks for the robustness test were MP3 compression, echo attack, and sub woofer boost. The MP3 compression was performed by a tool of Cool Edit Pro 2.0. The specification of MP3 was CBR(Constant Bit Rate) 128kbps, 44,100Hz, and stereo. The echo attack had the echo with initial volume 70%, decay 75%, and delay 100msec. The sub woofer boost attack was a modification attack of low frequency part in the Fourier coefficients. The test results showed the proposed algorithm is robust to the attacks. In the MP3 attack, the strength of the watermark information is not affected, and then the watermark can be detected from all of the sample audios. In the sub woofer boost attack, the watermark was detected when the strength is 0.3. Also, in the case of echo attack, the watermark can be identified if the strength is greater and equal than 0.5.