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A study on Evaluating Validity of SNR Calculation Using a Conventional Two Region Method in MR Images Applied a Multichannel Coil and Parallel Imaging Technique (다중채널코일과 병렬영상기법 이용 시 두영역측정법을 사용한 신호대잡음비 측정의 문제점)

  • Choi, Kwan-Woo;Son, Soon-Yong;Min, Jung-Whan;Kwon, Kyung-Tae;Yoo, Beong-Gyu;Lee, Jong-Seok
    • Journal of radiological science and technology
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    • v.38 no.4
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    • pp.403-410
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    • 2015
  • The purpose of this study was to investigate the problems of a signal to noise ratio measurement using a two region measurement method that is conventionally used when using a multi-channel coil and a parallel imaging technique. As a research method, after calculating the standard SNR using a single channel head coil of which coil satisfies three preconditions when using a two region measurement method, we made comparisons and evaluations after calculating an SNR by using a two region measurement method of which method is problematic because it is used without considering the methods recommended by reputable organizations and the preconditions at the time of using a multi-channel coil and a parallel imaging technique. We found that a two region measurement method using a multi-channel coil and a parallel imaging technique shows the highest relative standard deviation, and thus shows a low degree of precision. In addition, we found out that the difference of SNR according to ROI location was very high, and thus a spatial noise distribution was not uniform. Also, 95% confidence interval through Blend-Altman plot is the widest, and thus the conformity degree with a two region measurement method using the standard single channel head coil is low. By directly comparing an AAPM method, which serves as a standard of a performance evaluation test of a magnetic resonance imaging device under the same image acquisition conditions, an NEMA method which can accurately determine the noise level in a signal region and the methods recommended by manufacturers of a magnetic resonance imaging device, there is a significance in that we quantitatively verified the inaccurate problems of a signal to noise ratio using a two region measurement method when using a multi-channel coil and a parallel imaging technique of which method does not satisfy the preconditions that researchers could overlook.

A Study on Rail Vibration and Its Reduction Plan in Central Daejeon Area (대전 도심지역의 철도진동의 영향과 대책)

  • Ryu, Myoung-Ik;Suh, Man-Cheol;Lee, Won-Kook
    • Journal of the Korean Geophysical Society
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    • v.3 no.4
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    • pp.269-280
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    • 2000
  • Rail vibration in city zone is becoming a serious environmental problem. In order to make a reduction plan for rail vibration, the research was conducted in which many experiments to measure actual rail vibration along the railroad through the central Deajeon area. A digital vibration level meter was used to measure rail vibration. Vibration levels of Z-axis were measured at every second for the duration of the train passing. The measuring station was placed at every 5m for the distance of 55m. A total of 353 different sets of vibration level were obtained. The signals were processed to get $L_{10}$ value and analyzed in terms of distance, train velocity, and number of trains. As a result, it has been found that rail vibration exceed the allowable vibraton limit of 60 dB, at the point of 25 m far from the railroad center, which is regulated by the las of vibration and noise. Train velocity was found to affect a little for vibration level within the zone. It was also found that a trench installed along a railroad could reduce vibration level up to approximately 10 percent. A model test was conducted to investigate the influence of the location and size of trench, on the transfer of vibration. A heavy steel ball was used to generate vibrations. On the basis obtained from this study, it could be concluded that the application of distance-attenuation and the installment of a trench along railroad could be applied as a reduction plan for rail vibration. Because limitions might exist to depend on the effect of distance attenuation, trenchs excavated along a railroad might be suggested as the most efficient solution to reduce railroad vibration.

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Principle and Recent Advances of Neuroactivation Study (신경 활성화 연구의 원리와 최근 동향)

  • Kang, Eun-Joo
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.2
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    • pp.172-180
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    • 2007
  • Among the nuclear medicine imaging methods available today, $H_2^{15}O-PET$ is most widely used by cognitive neuroscientists to examine regional brain function via the measurement of regional cerebral blood flow (rCBF). The short half-life of the radioactively labeled probe, $^{15}O$, often allows repeated measures from the same subjects in many different task conditions. $H_2^{15}O-$ PET, however, has technical limitations relative to other methods of functional neuroimaging, e.g., fMRI, including relatively poor time and spatial resolutions, and, frequently, insufficient statistical power for analysis of individual subjects. However, recent technical developments, such as the 3-D acquisition method provide relatively good image quality with a smaller radioactive dosage, which in turn results in more PET scans from each individual, thus providing sufficient statistical power for the analysis of individual subject's data. Furthermore, the noise free scanner environment $H_2^{15}O$ PET, along with discrete acquisition of data for each task condition, are important advantages of PET over other functional imaging methods regarding studying state-dependent changes in brain activity. This review presents both the limitations and advantages of $^{15}O-PET$, and outlines the design of efficient PET protocols, using examples of recent PET studies both in the normal healthy population, and in the clinical population.

Effects of vocal aerobic treatment on voice improvement in patients with voice disorders (성대에어로빅치료법이 음성장애환자의 음성개선에 미치는 효과)

  • Park, Jun-Hee;Yoo, Jae-Yeon;Lee, Ha-Na
    • Phonetics and Speech Sciences
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    • v.11 no.3
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    • pp.69-76
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    • 2019
  • This study aimed to investigate the effects of vocal aerobic treatment (VAT) on the improvement of voice in patients with voice disorders. Twenty patients (13 males, 7 females) were diagnosed with voice disorders on the basis of videostroboscopy and voice evaluations. Acoustic evaluation was performed with the Multidimensional voice program (MDVP) and Voice Range Profile (VRP) of Computerized Speech Lab (CSL), and aerodynamic evaluation with PAS (Phonatory Aerodynamic System). The changes in F0, Jitter, Shimmer, and NHR before and after treatment were measured by MDVP. F0 range and Energy range were measured with VRP before and after treatment, and the changes in Expiratory Volume (FVC), Phonation Time (PHOT), Mean Expiratory Airflow (MEAF), Mean Peak Air Pressure (MPAP), and Aerodynamic Efficiency (AEFF) with PAS. Videostroboscopy was performed to evaluate the regularity, symmetry, mucosal wave, and amplitude changes of both vocal cords before and after treatment. Voice therapy was performed once a week for each patient using the VAT program in a holistic voice therapy approach. The average number of treatments per patient was 6.5. In the MDVP, Jitter, Shimmer, and NHR showed statistically significant decreases (p < .001, p < .01, p < .05). VRP results showed that Hz and semitones in the frequency range improved significantly after treatment (p < .01, p < .05), as did PAS, FVC, and PHOT (p < .01, p < .001). The results for videostroboscopy, functional voice disorder, laryngopharyngeal reflux, and benign vocal fold lesions were normal. Thus, the VAT program was found to be effective in improving the acoustic and aerodynamic aspects of the voice of patients with voice disorders. In future studies, the effect of VAT on the same group of voice disorders should be studied. It is also necessary to investigate subjective voice improvement and objective voice improvement. Furthermore, it is necessary to examine the effects of VAT in professional voice users.

A comparison of acoustic measures among the microphone types for smartphone recordings in normal adults (정상 성인에서 스마트폰 녹음을 위한 마이크 유형 간 음향학적 측정치 비교)

  • Jeong In Park;Seung Jin Lee
    • Phonetics and Speech Sciences
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    • v.16 no.2
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    • pp.49-58
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    • 2024
  • This study aimed to compare the acoustic measurements of speech samples recorded from individuals with normal voices using various devices: the Computerized Speech Lab (CSL), a unidirectional wired pin-microphone (WIRED) suitable for smartphones, the built-in omnidirectional microphone (SMART) of smartphones, and Bluetooth-connected wireless earphones, specifically the Galaxy Buds2 Pro (WIRELESS). This study included 40 normal adults (12 males and 28 females) who had not visited an otolaryngologist for respiratory diseases within the past three months. Participants performed sustained vowel /a/ phonation for four seconds and reading tasks with sentences ("Walk") and paragraphs ("Autumn") in a sound-treated booth. Recordings were simultaneously conducted using the four different devices and synchronized based on the CSL-recorded samples for analysis using the MDVP, ADSV, and VOXplot programs. Compared with CSL, the Cepstral Spectral Index of Dysphonia (CSIDV, CSIDS) and Acoustic Voice Quality Index (AVQI) values were lower in the WIRED and higher in the SMART. The opposite trend was observed for the L/H spectral ratios (SRV and SRS), and the WIRELESS demonstrated task-specific discrepancies. Furthermore, both the fundamental frequency (F0) and the cepstral peak prominence of the vowel samples (CPPV) had intraclass correlation coefficient (ICC) values above 0.9, indicating high reliability. These variables, F0 and CPPV were considered highly reliable for voice recordings across different microphone types. However, caution should be exercised when analyzing and interpreting variables such as the SR, CSID, and AVQI, which may be influenced by the type of microphone used.

A Morphologic Study of head and face for Sasang Constitution (사상체질별(四象體質別) 두면부(頭面部)의 형태학적(形態學的) 특징(特徵))

  • Ko, Byung-Hee;Song, Il-Byung;Cho, Yong-Jin;Choi, Chang-Seok;Kim, Jong-Weon;Hong, Suck-CHull;Lee, Eui-Ju;Lee, Sang-Yong;Seo, Jeong-Sug
    • Journal of Sasang Constitutional Medicine
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    • v.8 no.1
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    • pp.101-186
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    • 1996
  • The clinical application of constitutional Diagnosis is the most important part of Sasang constitutional medicine. It has been studied in various way. However, the study of morphologic characteristics on the face is applied for the first time. For quantitative analysis of the correlation between the sasang constitution and the shape of the face, the head-facial part of 170 cases were measured by Martin's measurement and analysis of a) the measurement value of height and the component ratio from the Gnathion to each part of face by constitution. b) the measurement value of depth and the component ratio from T-projected to each part of the face by constitution. c) the measurement value of breadth and component ratio between each parts of the facial breadth by constitution. d) the ratio of square on every part of face by constitution. e) the characteristics on each part of the face by constitution. f) the contour line of the forehead. g) the result of discriminant analysis about the constitution. Authors obtained the results from the study as follows; 1. The characteristics of Taeum-IN (1) The measurement value of Height, Breadth, T-Projected had a tendency to maximum value in general. (2) The value of lower opthal height and the square of lower opthal part was maximum. (3) The value of Pronasal T-projected length and Subnasal T-projected length was minimum, so Taeum-In has characteristics of depression in middle face, nasal part. (4) In the ratio of Breadth, T-Projected, T-Projected was minimum. (5) It was maximum that the square of nose, Alare, Middle face, Lower face and it was minimum that the square of eye. The square of nose, Alare, Middle facc, Lower face was maximum and the square of eye was minimum. (6) The curvature of the eyebrow was minimum. (7) The projection of jaw (Pogonion T-projection length) was maximum. (8) The breadth of eye was minimum. (9) There was a tendency that the projection of the forehead to the right in general. 2. The characteristics of Soeum-In (1) In all cases of projected length the measurement value was minimum. (2) The value of lower opthal height and the square of lower opthal part was minimum. (3) By the Pupulare T-projected length, the value of Pronasal T-projected length and Subnasal T-projected length was minimum, so the Soeum In's face shape is flat. (4) The square of eye, mouth, forehead was maximum and the square of nose, Alare, Middle face, Lower face was minimum. (5) The curvature of the eyebrow was maximum. (6) The projection of mouth was minimum. (7) The jaw was flat. (8) The breadth of eye was maximum. (9) There was a tendency that the projection of the forehead to the left in general. 3. The characteristics of Soyang-In. (1) In most cases of 고경 length the measurement value was minimum. (2) By the Pupulare T-projected length, each ratio of projected length was maximum, so the Soyang-In's face shape has many protrusions (3) In the ratio of Breadth, T-Projected, T-Projected was maximum. (4) The square of mouth was minimum. (5) The inclination of the forehead was minimum. (6) The projection of mouth was maximum. (7) The breadth of eye was minimum. (8) There was a tendency that the projection of the forehead to the left in general. (9) The middle face was protruded. 4. Discriminant about the constitution. According to the result of discriminant, the accuracy probability of discriminant was 85.58% in total and Taeum-In was 90.5%, Soeum-In was 70.8%, Soyang-In was 89.5%. The accuracy probability of discriminant about 3 constitutional group increased by 49.03% than the accident probility 36.55% 5. Suggestion (1) The study which gather and analysis the data should be continued. (2) The study which subdivide the characteristics of each part of the face by the constitution should be continued. (3) The analysis method about Moire should be supplement. (4) The study about the morphologic characteristics of the whole body should be continued. (5) Computer program of constitution diagnosis should be developed. (6) To increase utility of this method, the measurement should be automation.

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Female External Genitalia and Urethra on MR Imaging: Optimal Pulse Sequence and Comparison of Anatomy in Premenopausal and Postmenopausal Women (여성 외부 생식기와 요도의 자기공명영상 소견: 적합한 영상기법과 폐경 전후의 해부학적 변화 비교)

  • Whang, Shin-Young;Ahn, Kyung-Sik;Sung, Deuk-Jae;Park, Beom-Jin;Kim, Min-Ju;Cho, Sung-Bum;Lee, Nam-Joon
    • Investigative Magnetic Resonance Imaging
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    • v.15 no.2
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    • pp.146-153
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    • 2011
  • Purpose : To describe normal anatomy and compare the differences of external genital organs and urethra on MR imaging in pre- and postmenopausal women. Materials and Methods : A total of 19 pre- and 18 postmenopausal healthy women underwent pelvis MR imaging at 1.5 T. Two radiologists retrospectively scored and compared the image quality of female external genitalia and urethra on axial T2-weighted images (T2WI) and axial fat-suppressed contrast-enhanced T1-weighted images (FSCE-T1WI) by using Wilcoxon signed ranks test. The radiologists compared the wall thickness or size of external genital organs and urethra on FSCE-T1WI between two groups by using Student t test. Results : Image quality was better with FSCE-T1WI than with T2WI in all subjects (p < 0.05). The vestibular bulb, clitoris and labium minor were more clearly visualized on FSCE-T1WI in premenopausal subjects rather than in postmenopausal subjects (p < 0.05). The urethra had a target-like appearance with three layers in premenopausal and postmenopausal subjects. Postmenopausal subjects were observed to have significantly smaller vaginal wall thickness, urethral wall thickness and vestibular bulb width than premenopausal subjects (p < 0.05). Conclusion : The anatomy and morphologic changes of female external genital organs and urethra were well discernible on FSCE-T1WI.

Design and Fabrication for the Development of Auto Pattern Maker (자동취형기 개발을 위한 설계 및 제작)

  • Lee, Young-Il;Kim, Jung-Hee;Park, Jee-Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.3
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    • pp.231-239
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    • 2013
  • Purpose: To design and fabricate the auto pattern maker for the development. Methods: we got the necessary data, needed in design, by using CAD. Based on the these data, we fabricated the trial product for the development of the auto pattern maker. Results: The auto pattern maker were composed with combinations of many elements; pattern making assembly, control panel, frame attachment and prober unit. The pattern making assembly was comprised of the cutter, the pattern holder, pattern remover and silence cover which could minimize the sound during the cutting process. The control panel was designed to be connected and operated with the main printed circuit board. The prober could get the eye shape data by scanning of 1.8 degrees around the groove of the frame through the encoding data according to the address. After starting, scanning was carried out in two passes, i.e. one right-handed and one left-handed. Communication connector could send the eye shape data from auto pattern maker to outer system with the RS232C transmission system. By using the one-way analysis of variance, we got the error rate of cut pattern size for ${\Phi}22mm$, ${\Phi}55mm$ and ${\Phi}62mm$. Because F-value was 0.510 and p-value was 0.601, no statistically significant differences were found. Also, the mean cutting error of the auto pattern maker was 0.0274 mm. Conclusions: we could succeed in making the trial product by applying it to the development of the auto pattern maker. The role of this auto pattern maker is to find a exact required size of lens to fit the frame by measuring the frame. The acquired data are transferred to outer system for grinding and finishing with patternless process. Also, the trial product can produce pattern to fit the frame. Therefore, it was confidently expected that the optometrists could handily produce pattern to fit the frame with this trial product and dispense the ophthalmic lens because of its efficiency and convenience compared to the past.

The Purpose and background of this study (노인질환에 대한 한양방동시종합검진 결과에 대한 보고)

  • Gwon, Gyeong-Suk;Lee, Tae-Hwan;Song, Jeong-Mo;Kim, In-Seop;Yun, Ho-Yeong;Im, Jun-Gyu
    • The Journal of Korean Medicine
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    • v.15 no.2 s.28
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    • pp.9-27
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    • 1994
  • This study is to analyze of senile disease status and the social problem according to increased old ages, and then to find distributions of old man's diseases and health status efficiency of oriental-occidental contemporary health examination. And it is the first oriental-occidental contemporary health examination of old man performed by JeonJu Woosuk University Oriental Medicine Hospital and Woosuk-Clinic in nation. Methods The objects in this research are 641's old man of KimJe Gun's over 60's years performed medical examination at JeonJu Woosuk University Oriental- Mmedicine-Hospital and Woosuk-Clinic by oriental-occidental medical contemporary exam., from 1994, 24th June till 1994. 13th July. The 1st occident medical examination methods were consisted of chest x-ray check. blood and urine exam., measurement of blood pressure, visual power and audiometry. The Oriental medical examination methods were consisted of four diagnostics (望,聞,問,切), present illness. chief complaint, past history, families history, social history by question and SA Sang constitution test index. The results and conclusions The results and conclusions are the next: 1. In order of distribution. the athletic disease (75.8%),the digestive disease(43.4%), the circulatory disease(41.5%), the respiratory disease(22.3%), EENT disease(8.1%), the endocrinopathy(5.6%), and the genito-urinary disease(5.3%) are the results of the object about 641's old man, by the oriental-occidental medicine's contemporay exam. 2. Distribution of disease distiction are lumbago. gastritis and peptic ulcer. knee joint pain. heart disease. hypertension. chronic bronchitis. asthma. anemia. DM. Tbc. visual disturbance. CVA. etc in order. 3. Disease distribution according to age is almost high incident in 60-75years. Disease incidence is decreased except E.E.N.T disease in over 76years. 4. The relationships of disease and family history are: the 25.0% of CVA pts. has family history and the 11.6% of hypertension pts has family history. so they showed high relative family history. In addition the 5.6% of TBC pts. and the 2.6% of DM pts. have family history. 5. The relationships of disease and drinking are: Drinking proportion is the 36.4% in respiratory disease pts. the 34.7% in hypertension pts. the 33.3% in heart disease pts.. the 28.4% in digestive disease pts.. but because of no surveying drinking amount we can't know the absolut relationships of disease and drinking. 6. The relationships of Disease and smoking are: Smoking proportion is the 44.1% in respiratory disease pts.. the 38.0% in Heart disease pts.. the 29.8% in Hypertension pts.. but because of no surveying of smoking amount. we can't know the absolut relationships of disease and smoking. 7. Distribution of Sasang constitution is : Tae-eum-in 44.8%. So-yang-in 30.7%. So-eum-in 24.6%. Tae-yang-in 0.0%. And disease distribution of Sasang constitution distinction is ; Tae-eum-in has high incidence of circulation disease(50.0%) and respiratory disease(23.1%).So-yang-in has high incidence of athletics disease(77.7%) and EENT disease(12.2%), So-eum-in has high incidence of digestive disease(65.8%). 8. Distribution of abnormal result in occidental medical examination and oriental-occidental contemporal exam result is considerably different. This is the reason of needing oriental medicine exam, for characteristics of Senile. I think that the oriental-occidental contemporary examination in old man is much more effecient than only occident medical examination. This oriental-occidental contemporary examination has many defects because it is the first practice. To participate in the public health program efficiently. I think that we must improve lots of problems and present the model of the oriental-occidental contemporary examination and the project of oriental medicine's for public health.

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A Study on the Sasang Constitutional Distribution Among the People in the United States of America (북미지역주민(北美地域住民)의 사상체질(四象體質) 분포(分布)에 관(關)한 연구(硏究))

  • Koh, Byung-hee;Kim, Seon-ho;Park, Byung-gwan;Lavelle, Jonathan D;Tecun, Marianne;Anthony Jr., Ross;Hobbs, Ron;Zolli, Frank;Chin, Kyung-hee
    • Journal of Sasang Constitutional Medicine
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    • v.11 no.2
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    • pp.119-150
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    • 1999
  • In spite of recent remarkable recent development in both western and oriental medical sciences, there is still only a shallow understanding of individual differences for various prognoses of incurable diseases and immunopathy diseases. Nevertheless, the care, cure and prevention methods of Sasang Constitutional Medicine are broadly used as an effective treatment of incurable diseases like immunopathy diseases and stress-related diseases and diseases due to aging. In this sense, the establishment of classification norms is urgent and essential for the worldwide application of Sasang Constitutional Medicine(SCM). This study began with the confirmation process of whether Sasang Constitutional types exist in Americans. To accomodate for cultural differences, the distinguishing tool was readjusted so that Sasang Constitutional Types in Americans could be determined. Hence, the selected tool is the new QSCCII+, which is a newly revised English version of the QSCCII. QSCCII was made and standardized by Dept. of SCM in Kyung Hee Medical Center and Dr. Kim7). The evaluation methods of the old version were improved in the new QSCCII+ through necessary statistical manipulation. The original QSCCII was officially authorized by the Korean Society of Sasang Constitutional Medicine as the only computerized version of Sasang diagnostics. This study is the first attempt to design a new diagnostic tool for the classification of Sasang Constitutional types in North Americans with the revision of QSCCII. The subjects of this study were selected from the cooperative people among the students and staffs of the University of Bridgeport and the patients who visited the Clinic in the Health Science Center. This study takes for about 1 year from 1998. 8 to 1999. 8 The conclusions of the study can be summarized as follows: 1. Sasang constitutional types also exist in Americans. It can also naturally be inferred that Sasang Constitutional types exist in all human beings, for there are many different human races in America. 2. There are more So-Yang In's than any other types in American white people. This result confirms the hypothesis that there also exist Sasang Constitutional types in westerners. 3. The result of repetitive tests suggests that the new QSCCII+ is an effective diagnostic tool for westerners when we consider the constant diagnostic results of the QSCCII+. 4. Sasang Constitutional types exit in the sample group regardless of racial difference. 5. The question items that were not often checked by Americans need to be modified into more understandable expressions. 6. The standardization of diagnosis for Americans should be established by use of the QSCCII+ 7. It can be guessed that there are many Tae-yang In's among the 71 persons who could not be clearly classified by the QSCCII+. Due to the scarcity of Tae-yang-In in general, it is important to improve upon the discernability of the QSCC II+. 8. The results of the Sasang Constitutional distribution in North Americans are as follows: The percentage of So-yang In distribution in the sample group is 36.25%(87persons), that of Tae-eum In is 13.75%(33persons), and that of So-eum In is 20.41%(49persons).

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