• Journal of the Microelectronics and Packaging Society
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• v.14 no.2 s.43
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• pp.59-63
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• 2007

This paper presented a low-cost thick film gas sensor module, which was based on simple PCB (Printed Circuit Board) process. The proposed sensor module included a $NO_2/H_2$ gas sensor, a relative humidity sensor, and a heating element. The $NO_2/H_2$ gas and relative humidity sensors were realized by screen-printing $SnO_2,\;BaTiO_3$ nano-powders on IDTS (Interdigital Transducer) of a PCB substrate, respectively. At first 1% $H_2$ gas flowed into the sensor chamber. After 4 min, air filled the chamber while $H_2$ gas flow stopped. This experiment was performed repeatedly. The Identical procedure was used for the $NO_2$ detection. The result for sensing $H_2$ gas showed the increase of voltage from 0.8V to 3.5V due to the conductance increase and its reaction response time by hydrogen flow was 65 sec. $NO_2$ sensing results showed 2.7 V voltage drop due to the conductance decrease and its response time was 3 sec through a voltage monitoring.

• Journal of Environmental Science International
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• v.15 no.1
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• pp.85-94
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• 2006

The simultaneous analysis of multi-residual pesticides was developed using a gas chromatography (GC) method. In this study, a simple and reliable methodology was improved to detect 154 kinds of pesticides in sinseng extract sample by using a liquid-liquid extraction procedure, open column chromagraphy and chromatographic analysis by CC electron capture detector (ECD) and GC nitrogen-phosphorus detector (NPD). The 154 kinds of pesticides were classified in 4 groups according to the chemical structure. The extraction of pesticides was experimented with $70\%$ acetone and dichloromethane/petroleum ether in order, and cleaned up via open column chromatography $(3\times30cm)$ packed with florisil $(30g,\;130^{\circ}C,\;12hrs)$. The final extract was concentrated in a rotator evaporator at $40^{\circ}C$ until dryness. Then the residue was redissolved to 2ml with acetone, and analyzed by GC-ECD and GC-NPD. The applied concentration of pesticides was over $1\~10{\mu}g/ml$. The recovery tests were ranged from $70.7\%$ to $115.2\%$ with standard deviations between 0.3 and $5.7\%$ of the standard spiked to the ginseng extract sample (Group $I\~IV$). The limit of detection (LOD) ranged from 0.001 to $0.099{\mu}g/ml$ (Group $I\~IV$). The 9 kinds of pesticides were not detected. The developed method was applied satisfactory to the determination of the 154 kinds of pesticides in the ginseng extract with good reproducibility and accuracy.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.3
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• pp.112-119
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• 2018

Objectives: Temporomandibular joint ankylosis (TMJA) is a joint pathology caused by bony and/or fibrous adhesion of the joint apparatus, resulting in partial or total loss of function. Materials and Methods: This is a retrospective study conducted between 2012 and 2016 in the northwest region of Nigeria. The data retrieved includes gender, age, etiology of ankylosis, duration of ankylosis, laterality of ankylosis, type of imaging technique, type of airway management, types of incision, surgical procedure, mouth opening, interpositional materials used, and complications. Results were presented as simple frequencies and descriptive statistics. Results: Thirty-six patients with TMJA were evaluated during the study period. There were 21 males (58.3%) and 15 females (41.7%), yielding a male:female ratio of 1.4:1. The patients' age ranged from 5 to 33 years with $mean{\pm}standard$ deviation ($13.8{\pm}6.6years$). Thirty-five cases (97.2%) were determined to be true/bony ankylosis, while only 1 case (2.8%) was false/fibrous ankylosis. Most of the TMJA cases (16 cases, 44.4%) were secondary to a fall. In our series, the most commonly utilized incision was the Bramley-Al-Kayat (15 cases, 41.7%). The mostly commonly performed procedures were condylectomies and upper ramus ostectomies (12 cases each, 33.3%), while the most commonly used interpositional material was temporalis fascia (14 cases, 38.9%). The complications that developed included 4 cases (11.1%) of severe hemorrhage, 1 case (2.8%) of facial nerve palsy, and 1 case (2.8%) of re-ankylosis. Conclusion: Plain radiographs, with their shortcomings, still have significant roles in investigating TMJA. Aggressive postoperative physiotherapy for a minimum of 6 months is paramount for successful treatment.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.5
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• pp.486-492
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• 2004

In this paper, we newly propose the binary CA-CDMA(constant amplitude CDMA) system using pre-coding method to solve the high PAPR problem caused by multi-user signal transmission in the CDMA system. 4-user CA-CDMA, the basis of proposed binary CA-CDMA system, makes binary output signal for 4 input users. It produces the output of binary(${\pm}$2) amplitude by using a parity signal resulting from the XOR operation of 4 users data. Another sub-channel or more bandwidth is not necessary because it is transmitted together with user data and can be easily recovered in the receiver. The extension of the number of users can be possible by the simple repetition of the basic binary 4-user CA-CDMA. For example, binary 16-user CA-CDMA is made easily by allocating the four 4-user CA-CDMA systems in parallel and leading the four outputs to the fifth 4-user CA-CDMA system as input, because the output signal of each 4-user CA-CDMA is also binary. By the same extension procedure, binary 64 and 256-user CA-CDMA systems can be made with the constant amplitude. As a result, the code rate of this proposed CA-CDMA system is just 1 and binary CA-CDMA does not change the transmission rate with the constant output signal(PAPR = 0 ㏈). Therefore, the power efficiency of the HPA can be maximized without the nonlinear distortion. From the simulation results, it is verified that the conventional CDMA system has multi-level output signal, but the proposed binary CA-CDMA system always produces binary output. And it is also found that the BER of conventional CDMA system is increased by nonlinear HPA, but the BER of proposed binary CA-CDMA system is not changed.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.2
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• pp.161-167
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• 2010

Purpose: The aim of this study was to help the rapid and effective eye-tests of old patients by developing an optometric questionnaire for the elderly suitable for optical shops in Korea. Methods: We surveyed several previous studies about the age-related changes of the eye, and deduced 10 items which were appropriate for optometric eye-tests. Excluding the items that could be easily found in a routine eye-test and that was just physiological changes, we principally chose anomaly items which could be catched by simple oral questions. The questionnaire was mainly composed of clinically important items that were frequently observed. Results: To diagnose optometric symptoms related to eye-aging, we listed 15 questions on the questionnaire for the elderly. Each of the 15 questions was respectively about the decline in the amplitude of accommodation (no.1), anisometropia (no.2), xerophthalmia (no.3), muscae volitantes (no.4-5), dark adaptation (no.6) light and dark adaptation (no.7), contrast sensitivity (no.8), contrast sensitivity and anisometropia (no.9), contrast sensitivity and colour vision (no.10), the field of view (no.11), stereoscopic vision (no.12), colour vision (no.13), cataract (no.14), and presbyopia (no.15). Each question was easy to understand and related to the generally observed symptoms. Conclusions: Our optometric questionnaire for the elderly, which was developed by the procedure mentioned above, was expected to be a help for examining the aging eye and offer the basis of eye-tests of older patients in Korean optical shops.

• Journal of Korea Spatial Information System Society
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• v.4 no.2 s.8
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• pp.65-74
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• 2002

The CBD(component based development) method has recently been on the rise as the main current among all fields of developing Information Systems. The developing system by building and integrating of components is encouraged in GIS sphere. Business domain which considerably identifies components occupies GIS shpere rather then any other sphere. Arithmetic function is quite needed in GIS sphere but non-arithmetic functions are also used in GIS sphere as well as in enterprise sphere. Component is characterized by ensuring the reuse of itself. The efficiency of reusing component is promoted as the component is functionally simple and is packed to a minimum. The GIS Component Extraction Method has already been presented in several studies but this study is about the GIS Component Extraction by the Affinity Analysis Method. CBD uses UML on a basis and the core of the UML is consisted of the use case and the class. The purpose of the Affinity Analysis is a study how relate between the use case and the class in a certain business domain and then the results identify the component. The Affinity Analysis is useful not only in GIS but also in every business domain and is considered to be popular as the procedure of this method is not complex at all.

• Journal of Yeungnam Medical Science
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• v.15 no.2
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• pp.297-305
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• 1998

Recently, several alternatives have been attempted in the management of benign prostatic hyperplasia (BPH) to reduce morbidity of traditional transurethral resection of the prostate (TURP). Among new modalities, transurethral electrovaporization (TEVP) is considered as a promising alternative. To evaluate the safety and initial efficacy of JEVP using the roller loop electrode (ProSurg Inc. USA) on BPH patients, we compared the results of TEVP with those of TURP and visual laser ablation of the prostate (VLAP). In this study, a total of 115 patients with symptomatic BPH were underwent TEVP (n=17), TURP (n=59) or VLAP (n=39) since 1995. Before treatment, patients were evaluated with an International Prostate Symptom Score (IPSS) and the measurement of maximal uroflow rate (MFR) and postvoid residual urine (PVR). After treatment, the operative and hospital records were reviewed. The uroflowmetry and IPSS were re-evaluated 3-10 months after treatment. In clinical outcome of re-evaluation compared to the preoperative parameters, there was a clinically significant improvement in three procedures. TEVP resulted in 62% reduction in IPSS (TURP, 73% : VLAP, 69%), 84% improvement in MFR (TURP, 113% : VLAP, 91%), and 74% reduction in PVR (TURP, 88% : VLAP, 78%). TEVP had shorter duration of hospitalization and catheterization than the others. TEVP was associated with lower rates of treatment-related complication than TURP. In conclusions, TEVP is considered as a useful procedure to treat symptomatic BPH. And, the advantages of TEVP over TURP include excellent intraoperative hemostasis, lower morbidity, shorter hospital stay and simple technique. In addition the advantages over VLAP include lower cost, shorter duration of catheterization and early symptom improvement.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1689-1692
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• 2014

Background: An easy, reproducible and simple marker is needed to estimate phase of endometrial pathologic lesions such as hyperplasia and endometrial cancer and distinguish from pathologically normal results. We here aimed to clarify associations among neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), endometrial hyperplasia and cancer in patients with abnormal uterine bleeding. Materials and Methods: Patients (n=161) who were admitted with abnormal uterine bleeding and the presence of endometrial cells on cervical cytology or thick endometrium were investigated. The study constituted of three groups according to pathologic diagnosis. Group 1 included endometrial precancerous lesions like hyperplasia (n=63), group 2 included endometrial cancerous lesions (n=38) and group 3 was a pathologically normal group (n=60). Blood samples were obtained just before the curettage procedure and the NLR was defined as the absolute neutrophil count divided by the absolute lymphocyte count; similarly, PLR was defined as the absolute platelet count divided by the absolute lymphocyte count. Results: The white blood cell count was significantly higher in patients with cancer than in those with hyperplasia (p=0.005). The platelet count and neutrophil to lymphocyte ratio were significantly higher in patients with cancer than in control patients, but there was significantly no difference between patients with hyperplasia and other groups (p=0.001 and p=0.025 respectively). PLR was significantly lower in control subjects than in other groups (p<0.001), but there was no significant difference between patients with hyperplasia and those with cancer. Conclusions: PLR was significantly lower in control subjects than in other groups. Thus both hyperplasia and cancer may be differentiated from pathologically normal patients by using PLR. White blood cell count was significantly higher in patients with cancer than in those with hyperplasia and pathologically normal patients. Therefore white blood cell count may be used for discriminate hyperplasia to cancer. By using multiple inflammation parameters, discrimination may be possible among endometrial cancer, endometrial precancerous lesions and pathologically normal patients.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.38 no.10
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• pp.1-9
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• 2001

The MAC (Medium Access Control) protocol is needed for the OLT(Optical Line Termination) to allocate bandwidth to ONUs(Optical Network Units) and ONTs(Optical Network Terminations) dynamically in the ATM PON(Passive Optical Network). With the protocol, the OLT gathers ONUs' informations and provides grants efficiently to each ONU. Two important functions of the MAC protocol is the grant request procedure and the grant distribution algrithm. The latter has the greatest arithmetic portion in the TC(Transmission Convergence) module, occupies a relatively large portion of the overall chip area, has often been the limiting factor in terms of speed, and should be designed to guarantee the quality of service for various traffics. In this paper, we implement the MAC with the FPGA which can allocate grants dynamically according to the queue length information and the number of active ONUs and distribute grants uniformly to minimize the cell delay variation for each ONU. The structure of the MAC scheduler for the dynamic bandwidth assignment has a programmable look-up table. Also, it has a simple structure, the less chip area, and the lower delay time.

• Archives of design research
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• v.15 no.2
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• pp.91-100
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• 2002

Unlike a study related in language alone, rhetorical study of current time, composed with multi-culture, medias, communication, presents its own field that covers from the form of discourse(persuasive) to another form of discourse(not persuasive). If there was a study of making beautiful sentences for story and finding simple method of speech in Greek and roman period of an ancient time, it now a study in which one finds the essence of literary style or terminology in the expression of sentence. The taller case is especially important, given that the importance of what to express visually is on-going active procedure of this stuffy as itself an activity of communication. When a visual object persuades viewers, the activity of communication derives them to react and to understand the intention of an artist. The matter of how to speak is the matter of how to shape message persuasively. This persuasive method or technique is study of rhetoric. The three aspects (figurative, accentuating, mutating) of rhetorical expression of an illustration, the visual image can give fresh feelings to be in intimate relations with public. These rhetorical expressions also vitalize the story that is expressed on illustration with crisp image. It helps to attain expected effects while discovering essential meaning through the corresponding linguistic interpretation of an image. The study aims at the most effective way to communicate by figuring the most strong and direct illustrative message out. One of the method is to patternize illustrative expressions that are established from all kinds of shapes of Rhetoric. Therefore ,an operation of significance and an implication can shape an ultimate goal of this study from acknowledging the mechanism that modern illustration embraces.